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Bargagli M, Anderegg MA, Fuster DG. Effects of thiazides and new findings on kidney stones and dysglycemic side effects. Acta Physiol (Oxf) 2024:e14155. [PMID: 38698738 DOI: 10.1111/apha.14155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/08/2024] [Accepted: 04/22/2024] [Indexed: 05/05/2024]
Abstract
Thiazide and thiazide-like diuretics (thiazides) belong to the most frequently prescribed drugs worldwide. By virtue of their natriuretic and vasodilating properties, thiazides effectively lower blood pressure and prevent adverse cardiovascular outcomes. In addition, through their unique characteristic of reducing urine calcium, thiazides are also widely employed for the prevention of kidney stone recurrence and reduction of bone fracture risk. Since their introduction into clinical medicine in the early 1960s, thiazides have been recognized for their association with metabolic side effects, particularly impaired glucose tolerance, and new-onset diabetes mellitus. Numerous hypotheses have been advanced to explain thiazide-induced glucose intolerance, yet underlying mechanisms remain poorly defined. Regrettably, the lack of understanding and unpredictability of these side effects has prompted numerous physicians to refrain from prescribing these effective, inexpensive, and widely accessible drugs. In this review, we outline the pharmacology and mechanism of action of thiazides, highlight recent advances in the understanding of thiazide-induced glucose intolerance, and provide an up-to-date discussion on the role of thiazides in kidney stone prevention.
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Affiliation(s)
- Matteo Bargagli
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Swiss National Centre of Competence in Research (NCCR) Kidney.CH, University of Zürich, Zürich, Switzerland
- Department for Biomedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Manuel A Anderegg
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Swiss National Centre of Competence in Research (NCCR) Kidney.CH, University of Zürich, Zürich, Switzerland
- Department for Biomedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Swiss National Centre of Competence in Research (NCCR) Kidney.CH, University of Zürich, Zürich, Switzerland
- Department for Biomedical Research (DBMR), University of Bern, Bern, Switzerland
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2
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Bargagli M, Trelle S, Bonny O, Fuster DG. Thiazides for kidney stone recurrence prevention. Curr Opin Nephrol Hypertens 2024:00041552-990000000-00155. [PMID: 38606682 DOI: 10.1097/mnh.0000000000000990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
PURPOSE OF REVIEW Kidney stones are the most common condition affecting the kidney, and characterized by a high rate of recurrence. Thiazide and thiazide-like diuretics (thiazides) are commonly prescribed to prevent the recurrence of kidney stones. This review offers a comprehensive up-to-date assessment of the evidence supporting the use of thiazides for kidney stone recurrence prevention, highlights potential harms associated with treatment, and identifies areas of knowledge that require further investigation. RECENT FINDINGS The clinical routine to prescribe thiazides for kidney stone prevention has recently been challenged by the findings of the large NOSTONE trial that failed to show superiority of hydrochlorothiazide at doses up to 50 mg daily over placebo in preventing a composite of clinical or radiological recurrence in patients at high risk of recurrence. Yet, adverse events such as new onset diabetes mellitus and gout were more common in patients receiving hydrochlorothiazide compared to placebo. As demonstrated by a novel meta-analysis presented in this review encompassing all randomized placebo-controlled trials with thiazide monotherapy, current trial evidence does not indicate that thiazide monotherapy is significantly better than placebo in preventing kidney stone recurrence. SUMMARY Given the limited efficacy and possible adverse effects, we advocate for a restrictive use of thiazides for kidney stone recurrence prevention. Clearly, there remains a high unmet medical need for effective, targeted therapies to prevent recurrence of kidney stones.
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Affiliation(s)
- Matteo Bargagli
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital
| | - Sven Trelle
- CTU Bern, Department of Clinical Research, University of Bern, Bern
| | - Olivier Bonny
- Service of Nephrology, Fribourg State Hospital, University of Fribourg, Fribourg, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital
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Geraghty RM, Wilson I, Olinger E, Cook P, Troup S, Kennedy D, Rogers A, Somani BK, Dhayat NA, Fuster DG, Sayer JA. Routine Urinary Biochemistry Does Not Accurately Predict Stone Type Nor Recurrence in Kidney Stone Formers: A Multicentre, Multimodel, Externally Validated Machine-Learning Study. J Endourol 2023; 37:1295-1304. [PMID: 37830220 DOI: 10.1089/end.2023.0451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023] Open
Abstract
Objectives: Urinary biochemistry is used to detect and monitor conditions associated with recurrent kidney stones. There are no predictive machine learning (ML) tools for kidney stone type or recurrence. We therefore aimed to build and validate ML models for these outcomes using age, gender, 24-hour urine biochemistry, and stone composition. Materials and Methods: Data from three cohorts were used, Southampton, United Kingdom (n = 3013), Newcastle, United Kingdom (n = 5984), and Bern, Switzerland (n = 794). Of these 3130 had available 24-hour urine biochemistry measurements (calcium, oxalate, urate [Ur], pH, volume), and 1684 had clinical data on kidney stone recurrence. Predictive ML models were built for stone type (n = 5 models) and recurrence (n = 7 models) using the UK data, and externally validated with the Swiss data. Three sets of models were built using complete cases, multiple imputation, and oversampling techniques. Results: For kidney stone type one model (extreme gradient boosting [XGBoost] built using oversampled data) was able to effectively discriminate between calcium oxalate, calcium phosphate, and Ur on both internal and external validation. For stone recurrence, none of the models were able to discriminate between recurrent and nonrecurrent stone formers. Conclusions: Kidney stone recurrence cannot be accurately predicted using modeling tools built using specific 24-hour urinary biochemistry values alone. A single model was able to differentiate between stone types. Further studies to delineate accurate predictive tools should be undertaken using both known and novel risk factors, including radiomics and genomics.
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Affiliation(s)
- Robert M Geraghty
- Department of Urology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom
| | - Ian Wilson
- Biosciences Institute, Newcastle University, International Centre for Life, Newcastle Upon Tyne, United Kingdom
| | - Eric Olinger
- Translational and Clinical Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Paul Cook
- Department of Biochemistry, University Hospital Southampton, Southampton, United Kingdom
| | - Susan Troup
- Department of Biochemistry, Queen Elizabeth Hospital, Gateshead, United Kingdom
| | - David Kennedy
- Department of Biochemistry, Queen Elizabeth Hospital, Gateshead, United Kingdom
| | - Alistair Rogers
- Department of Urology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom
| | - Bhaskar K Somani
- Department of Urology, University Hospital Southampton, Southampton, United Kingdom
| | - Nasser A Dhayat
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department for Biomedical Research, University of Bern, Bern, Switzerland
| | - John A Sayer
- Translational and Clinical Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, United Kingdom
- The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, United Kingdom
- National Institute for Health Research Newcastle Biomedical Research Centre, Newcastle Upon Tyne, United Kingdom
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Kucharczyk P, Albano G, Deisl C, Ho TM, Bargagli M, Anderegg M, Wueest S, Konrad D, Fuster DG. Thiazides Attenuate Insulin Secretion Through Inhibition of Mitochondrial Carbonic Anhydrase 5b in β -Islet Cells in Mice. J Am Soc Nephrol 2023; 34:1179-1190. [PMID: 36927842 PMCID: PMC10356162 DOI: 10.1681/asn.0000000000000122] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 02/26/2023] [Indexed: 03/18/2023] Open
Abstract
SIGNIFICANCE STATEMENT Thiazide diuretics (thiazides) are among the most widely prescribed drugs worldwide, but their use is associated with glucose intolerance and new-onset diabetes mellitus. The molecular mechanisms remain elusive. Our study reveals that thiazides attenuate insulin secretion through inhibition of the mitochondrial carbonic anhydrase isoform 5b (CA5b) in pancreatic β cells. We furthermore discovered that pancreatic β cells express only one functional carbonic anhydrase isoform, CA5b, which is critical in replenishing oxaloacetate in the mitochondrial tricarboxylic acid (TCA) cycle (anaplerosis). These findings explain the mechanism for thiazide-induced glucose intolerance and reveal a fundamental role of CA5b in TCA cycle anaplerosis and insulin secretion in β cells. BACKGROUND Thiazide diuretics are associated with glucose intolerance and new-onset diabetes mellitus. Previous studies demonstrated that thiazides attenuate insulin secretion, but the molecular mechanisms remain elusive. We hypothesized that thiazides attenuate insulin secretion via one of the known molecular thiazide targets in β cells. METHODS We performed static insulin secretion experiments with islets of wild-type, Sodium/chloride co-transporter (NCC) (SLC12A3), and sodium-driven chloride/bicarbonate exchanger (NDCBE) (SLC4A8) knock-out (KO) mice and with murine Min6 cells with individual knockdown of carbonic anhydrase (CA) isoforms to identify the molecular target of thiazides in β cells. CA isoform 5b (CA5b) KO mice were then used to assess the role of the putative thiazide target CA5b in β -cell function and in mediating thiazide sensitivity in vitro and in vivo . RESULTS Thiazides inhibited glucose- and sulfonylurea-stimulated insulin secretion in islets and Min6 cells at pharmacologically relevant concentrations. Inhibition of insulin secretion by thiazides was CO 2 /HCO 3- -dependent, not additive to unselective CA inhibition with acetazolamide, and independent of extracellular potassium. By contrast, insulin secretion was unaltered in islets of mice lacking the known molecular thiazide targets NCC or NDCBE. CA expression profiling with subsequent knockdown of individual CA isoforms suggested mitochondrial CA5b as a molecular target. In support of these findings, thiazides significantly attenuated Krebs cycle anaplerosis through reduction of mitochondrial oxaloacetate synthesis. CA5b KO mice were resistant to thiazide-induced glucose intolerance, and thiazides did not alter insulin secretion in CA5b KO islets. CONCLUSIONS Thiazides attenuate insulin secretion via inhibition of the mitochondrial CA5b isoform in β cells of mice.
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Affiliation(s)
- Patrycja Kucharczyk
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Giuseppe Albano
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Christine Deisl
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Tin Manh Ho
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Matteo Bargagli
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Manuel Anderegg
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Stephan Wueest
- Division of Pediatric Endocrinology and Diabetology, University Children's Hospital, University of Zürich, Zürich, Switzerland
- Children's Research Center, University Children's Hospital, University of Zürich, Zürich, Switzerland
| | - Daniel Konrad
- Division of Pediatric Endocrinology and Diabetology, University Children's Hospital, University of Zürich, Zürich, Switzerland
- Children's Research Center, University Children's Hospital, University of Zürich, Zürich, Switzerland
| | - Daniel G. Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
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Legay C, Haeusermann T, Pasquier J, Chatelan A, Fuster DG, Dhayat N, Seeger H, Ritter A, Mohebbi N, Ernandez T, Stoermann C, Buchkremer F, Segerer S, Wuerzner G, Ammor N, Roth B, Wagner CA, Bonny O, Bochud M. Differences in the food consumption between kidney stone formers and non-formers in the Swiss Kidney Stone Cohort. J Ren Nutr 2023:S1051-2276(23)00067-5. [PMID: 37120128 DOI: 10.1053/j.jrn.2023.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 04/09/2023] [Accepted: 04/16/2023] [Indexed: 05/01/2023] Open
Abstract
OBJECTIVE Diet has a major influence on the formation and management of kidney stones. However, kidney stone formers' diet is difficult to capture in a large population. Our objective was to describe the dietary intake of kidney stone formers in Switzerland and to compare it to non-stone formers. METHODS We used data from the Swiss Kidney Stone Cohort (n=261), a multicentric cohort of recurrent or incident kidney stone formers with additional risk factors, and a control group of CT-scan proven non-stone formers (n=197). Dieticians conducted two consecutive 24-h dietary recalls, using structured interviews and validated software (GloboDiet). We took the mean consumption per participant of the two 24-h dietary recalls to describe the dietary intake and used two-part models to compare the two groups. RESULTS The dietary intake was overall similar between stone and non-stone formers. However, we identified that kidney stone formers had a higher probability of consuming cakes and biscuits (odds ratio, OR[95% CI] =1.56[1.03; 2.37]) and soft drinks (OR=1.66[1.08; 2.55]). Kidney stone formers had a lower probability of consuming nuts and seeds (OR =0.53[0.35; 0.82]), fresh cheese (OR=0.54[0.30; 0.96]), teas (OR=0.50[0.3; 0.84]), and alcoholic beverages (OR=0.35[0.23; 0.54]), especially wine (OR=0.42[0.27; 0.65]). Furthermore, among consumers, stone formers reported smaller quantities of vegetables (β coeff[95% CI]= - 0.23[- 0.41; - 0.06]), coffee (β coeff= - 0.21[- 0.37; - 0.05]), teas (β coeff= - 0.52[- 0.92; - 0.11]) and alcoholic beverages (β coeff= - 0.34[- 0.63; - 0.06]). CONCLUSION Stone formers reported lower intakes of vegetables, tea, coffee, and alcoholic beverages, more specifically wine, but reported drinking more frequently soft drinks than non-stone formers. For the other food groups, stone formers and non-formers reported similar dietary intakes. Further research is needed to better understand the links between diet and kidney stone formation and develop dietary recommendations adapted to the local settings and cultural habits.
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Affiliation(s)
- Constance Legay
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland; Center for Primary Care and Public Health (Unisanté), Department of Epidemiology and Health Systems, University of Lausanne, Lausanne, Switzerland; National Center of Competence in Research NCCR Kidney.CH
| | | | - Jérôme Pasquier
- Center for Primary Care and Public Health (Unisanté), Department Formation, Research and Innovation, University of Lausanne, Lausanne, Switzerland
| | - Angeline Chatelan
- Department of Nutrition and Dietetics, Geneva School of Health Sciences, HES-SO University of Applied Sciences and Arts Western, Geneva, Switzerland; Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- National Center of Competence in Research NCCR Kidney.CH; Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Nasser Dhayat
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Harald Seeger
- Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
| | - Alexander Ritter
- Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
| | - Nilufar Mohebbi
- Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
| | - Thomas Ernandez
- Service of Nephrology, Geneva University Hospitals, Geneva, Switzerland
| | | | - Florian Buchkremer
- Nephrologie, Dialyse und Transplantation, Kantonsspital Aarau, Aarau, Switzerland
| | - Stephan Segerer
- Nephrologie, Dialyse und Transplantation, Kantonsspital Aarau, Aarau, Switzerland
| | - Grégoire Wuerzner
- Service of Nephrology and Hypertension, Lausanne University Hospital, Lausanne, Switzerland
| | - Nadia Ammor
- Service of Nephrology and Hypertension, Lausanne University Hospital, Lausanne, Switzerland
| | - Beat Roth
- Department of Urology, Lausanne University Hospital, CHUV, University of Lausanne, Switzerland
| | - Carsten A Wagner
- National Center of Competence in Research NCCR Kidney.CH; Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Olivier Bonny
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland; National Center of Competence in Research NCCR Kidney.CH; Service of Nephrology and Hypertension, Lausanne University Hospital, Lausanne, Switzerland; Service of Nephrology, Fribourg State Hospital, Fribourg, Switzerland.
| | - Murielle Bochud
- Center for Primary Care and Public Health (Unisanté), Department of Epidemiology and Health Systems, University of Lausanne, Lausanne, Switzerland; National Center of Competence in Research NCCR Kidney.CH
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6
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Dhayat NA, Bonny O, Roth B, Christe A, Ritter A, Mohebbi N, Faller N, Pellegrini L, Bedino G, Venzin RM, Grosse P, Hüsler C, Koneth I, Bucher C, Del Giorno R, Gabutti L, Mayr M, Odermatt U, Buchkremer F, Ernandez T, Stoermann-Chopard C, Teta D, Vogt B, Roumet M, Tamò L, Cereghetti GM, Trelle S, Fuster DG. Hydrochlorothiazide and Prevention of Kidney-Stone Recurrence. N Engl J Med 2023; 388:781-791. [PMID: 36856614 DOI: 10.1056/nejmoa2209275] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
BACKGROUND Nephrolithiasis is one of the most common conditions affecting the kidney and is characterized by a high risk of recurrence. Thiazide diuretic agents are widely used for prevention of the recurrence of kidney stones, but data regarding the efficacy of such agents as compared with placebo are limited. Furthermore, dose-response data are also limited. METHODS In this double-blind trial, we randomly assigned patients with recurrent calcium-containing kidney stones to receive hydrochlorothiazide at a dose of 12.5 mg, 25 mg, or 50 mg once daily or placebo once daily. The main objective was to investigate the dose-response effect for the primary end point, a composite of symptomatic or radiologic recurrence of kidney stones. Radiologic recurrence was defined as the appearance of new stones on imaging or the enlargement of preexisting stones that had been observed on the baseline image. Safety was also assessed. RESULTS In all, 416 patients underwent randomization and were followed for a median of 2.9 years. A primary end-point event occurred in 60 of 102 patients (59%) in the placebo group, in 62 of 105 patients (59%) in the 12.5-mg hydrochlorothiazide group (rate ratio vs. placebo, 1.33; 95% confidence interval [CI], 0.92 to 1.93), in 61 of 108 patients (56%) in the 25-mg group (rate ratio, 1.24; 95% CI, 0.86 to 1.79), and in 49 of 101 patients (49%) in the 50-mg group (rate ratio, 0.92; 95% CI, 0.63 to 1.36). There was no relation between the hydrochlorothiazide dose and the occurrence of a primary end-point event (P = 0.66). Hypokalemia, gout, new-onset diabetes mellitus, skin allergy, and a plasma creatinine level exceeding 150% of the baseline level were more common among patients who received hydrochlorothiazide than among those who received placebo. CONCLUSIONS Among patients with recurrent kidney stones, the incidence of recurrence did not appear to differ substantially among patients receiving hydrochlorothiazide once daily at a dose of 12.5 mg, 25 mg, or 50 mg or placebo once daily. (Funded by the Swiss National Science Foundation and Inselspital; NOSTONE ClinicalTrials.gov number, NCT03057431.).
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Affiliation(s)
- Nasser A Dhayat
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Olivier Bonny
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Beat Roth
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Andreas Christe
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Alexander Ritter
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Nilufar Mohebbi
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Nicolas Faller
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Lisa Pellegrini
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Giulia Bedino
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Reto M Venzin
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Philipp Grosse
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Carina Hüsler
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Irene Koneth
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Christian Bucher
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Rosaria Del Giorno
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Luca Gabutti
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Michael Mayr
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Urs Odermatt
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Florian Buchkremer
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Thomas Ernandez
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Catherine Stoermann-Chopard
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Daniel Teta
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Bruno Vogt
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Marie Roumet
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Luca Tamò
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Grazia M Cereghetti
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Sven Trelle
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
| | - Daniel G Fuster
- From the Departments of Nephrology and Hypertension (N.A.D., N.F., B.V., L.T., G.M.C., D.G.F.), Urology (B.R.), and Radiology (A.C.), Inselspital, Bern University Hospital, and CTU Bern (M.R., S.T.), University of Bern, Bern, Service of Nephrology, Lausanne University Hospital, University of Lausanne, Lausanne (O.B.), the Department of Nephrology, University Hospital Zurich, Zurich (A.R., N.M.), the Department of Nephrology, Regional Hospital Lugano (L.P., G.B.), and Università della Svizzera Italiana (R.D.G., L.G.), Lugano, the Department of Nephrology, Cantonal Hospital Graubünden, Chur (R.M.V., P.G.), the Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen (C.H., I.K., C.B.), the Department of Internal Medicine, Regional Hospital of Bellinzona, Bellinzona (R.D.G., L.G.), the Medical Outpatient Department, University Hospital Basel, University of Basel, Basel (M.M.), the Department of Nephrology, Luzerner Kantonsspital LUKS, Lucerne (U.O.), the Division of Nephrology, Dialysis, and Transplantation, Cantonal Hospital Aarau, Aarau (F.B.), the Department of Nephrology, University Hospital Geneva, University of Geneva, Geneva (T.E., C.S.-C.), and the Nephrology Service, Centre Hospitalier du Valais Romand, Sion (D.T.) - all in Switzerland
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7
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Mueller L, Moser M, Prazak J, Fuster DG, Schefold JC, Zuercher P. Metformin's Role in Hyperlactatemia and Lactic Acidosis in ICU Patients: A Systematic Review. Pharmacology 2023; 108:213-223. [PMID: 36652938 DOI: 10.1159/000528252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 11/16/2022] [Indexed: 01/20/2023]
Abstract
INTRODUCTION Metformin-treated patients may experience severe hyperlactatemia or lactic acidosis (LA). LA often requires intensive-care-unit (ICU) treatment, and mortality rates are high. Here, we investigate the impact of renal dysfunction and renal replacement therapy (RRT) on the outcomes of critically ill patients with metformin-associated LA (MALA). Furthermore, we assessed associations between mortality and metformin dose, metformin plasma/serum concentrations, lactate level, and arterial pH. Finally, we investigated whether the recommended classification in MALA, metformin-unrelated LA, metformin-induced LA, and LA in metformin therapy appears useful in this regard. METHODS We performed a retrospective analysis based on a systematic PubMed search for publications on hyperlactatemia/LA in metformin-treated ICU patients from January 1995 to February 2020. Case-level data including demographics and clinical conditions were extracted, and logistic regression analyses were performed. RESULTS A total of 92 ICU patients were reported. Two of these patients had no comorbidities interfering with lactate metabolism. In the overall group, arterial pH, lactate levels, and metformin plasma/serum concentrations were similar in survivors versus non-survivors. Ingested daily metformin doses and plasma/serum creatinine levels were significantly higher in survivors versus non-survivors (p = 0.007 vs. p = 0.024, respectively). Higher plasma/serum creatinine levels, higher lactate levels, and lower arterial pH were all associated with patients receiving RRT (all p < 0.05). Overall mortality was 22% (20 out of 92 patients) and did not differ between the RRT and non-RRT groups. CONCLUSION Mortality is high in ICU patients with metformin-associated hyperlactatemia/LA. Unexpectedly, higher ingested metformin dose and plasma/serum creatinine were associated with a better outcome. Survival was similar in patients with or without need for RRT.
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Affiliation(s)
- Livia Mueller
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Michel Moser
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Josef Prazak
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Joerg C Schefold
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Patrick Zuercher
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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8
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Ho TM, Berger S, Müller P, Simonin C, Reymond JL, Von Ballmoos C, Fuster DG. Physiological and Molecular Function of the Sodium/Hydrogen Exchanger NHA2 (SLC9B2). Chimia (Aarau) 2022; 76:1019-1024. [PMID: 38069797 DOI: 10.2533/chimia.2022.1019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 10/05/2022] [Indexed: 12/18/2023] Open
Abstract
NHA2, also known as SLC9B2, is an orphan intracellular Na+/H+ exchanger (NHE) that has been associated with arterial hypertension and diabetes mellitus in humans. The objective of this NCCR TransCure project was to define the physiological and molecular function of NHA2, to develop a high resolution kinetic transport assay for NHA2 and to identify specific and potent compounds targeting NHA2. In this review, we summarize the results of this highly interdisciplinary and interfaculty effort, led by the groups of Proffs. Jean-Louis Reymond, Christoph von Ballmoos and Daniel Fuster.
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Affiliation(s)
- Tin Manh Ho
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern.
| | - Stephan Berger
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Switzerland.
| | - Philipp Müller
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Switzerland.
| | - Céline Simonin
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Switzerland.
| | - Christoph Von Ballmoos
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Switzerland.
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern.
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9
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Bargagli M, Vetsch A, Anderegg MA, Dhayat NA, Huynh-Do U, Faller N, Vogt B, Ferraro PM, Fuster DG. Tolvaptan treatment is associated with altered mineral metabolism parameters and increased bone mineral density in ADPKD patients. Nephrol Dial Transplant 2022:6780211. [DOI: 10.1093/ndt/gfac298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Autosomal-dominant polycystic kidney disease (ADPKD) is characterized by a unique bone and mineral phenotype. The impact of Tolvaptan treatment on mineral metabolism and bone mineral density is unknown.
Methods
We conducted an analysis in the Bern ADPKD registry, a prospective observational cohort study. Mineral metabolism parameters were measured at baseline and every 12 months thereafter. Bone mineral density was determined by dual-energy X-ray absorptiometry at baseline and after 3 years. Multivariable mixed-effects regression models were applied to assess changes in mineral metabolism parameters and bone mineral density associated with Tolvaptan treatment.
Results
A total of 189 participants (122 without and 67 with subsequent Tolvaptan treatment) were included in the analysis. During follow-up, Tolvaptan treatment was associated with increased bone mineral density at the femoral neck (β 0.092; 95% CI 0.001, 0.183; p = 0.047). In addition, Tolvaptan treatment was associated with higher plasma magnesium (β 0.019; 95% CI 0.001, 0.037; p = 0.037), bicarbonate (β 0.972; 95% CI 0.242, 1.702; p = 0.009) and urine pH (β 0.214; 95% CI 0.056, 0.372; p = 0.008), and lower parathyroid hormone (β −0.191; 95% CI −0.328, −0.053; p = 0.006), 1,25-(OH)2-Vitamin D3 (β −0.126; 95% CI −0.235, −0.164; p = 0.024) and fractional urinary magnesium excretion (β −0.473; 95% CI −0.622, −0.324; p < 0.001).
Conclusions
Chronic Tolvaptan treatment is associated with increased femoral bone mineral density and significant changes in both mineral metabolism and acid-base parameters in ADPKD patients.
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Affiliation(s)
- Matteo Bargagli
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern , Bern , Switzerland
- Università Cattolica del Sacro Cuore , Rome , Italy
- U.O.C. Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS , Rome , Italy
| | - Andri Vetsch
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern , Bern , Switzerland
| | - Manuel A Anderegg
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern , Bern , Switzerland
| | - Nasser A Dhayat
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern , Bern , Switzerland
| | - Uyen Huynh-Do
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern , Bern , Switzerland
| | - Nicolas Faller
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern , Bern , Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern , Bern , Switzerland
| | - Pietro Manuel Ferraro
- Università Cattolica del Sacro Cuore , Rome , Italy
- U.O.C. Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS , Rome , Italy
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern , Bern , Switzerland
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10
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Olinger E, Schaeffer C, Kidd K, Elhassan EAE, Cheng Y, Dufour I, Schiano G, Mabillard H, Pasqualetto E, Hofmann P, Fuster DG, Kistler AD, Wilson IJ, Kmoch S, Raymond L, Robert T, Eckardt KU, Bleyer AJ, Köttgen A, Conlon PJ, Wiesener M, Sayer JA, Rampoldi L, Devuyst O. An intermediate-effect size variant in UMOD confers risk for chronic kidney disease. Proc Natl Acad Sci U S A 2022; 119:e2114734119. [PMID: 35947615 PMCID: PMC9388113 DOI: 10.1073/pnas.2114734119] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 05/04/2022] [Indexed: 12/12/2022] Open
Abstract
The kidney-specific gene UMOD encodes for uromodulin, the most abundant protein excreted in normal urine. Rare large-effect variants in UMOD cause autosomal dominant tubulointerstitial kidney disease (ADTKD), while common low-impact variants strongly associate with kidney function and the risk of chronic kidney disease (CKD) in the general population. It is unknown whether intermediate-effect variants in UMOD contribute to CKD. Here, candidate intermediate-effect UMOD variants were identified using large-population and ADTKD cohorts. Biological and phenotypical effects were investigated using cell models, in silico simulations, patient samples, and international databases and biobanks. Eight UMOD missense variants reported in ADTKD are present in the Genome Aggregation Database (gnomAD), with minor allele frequency (MAF) ranging from 10-5 to 10-3. Among them, the missense variant p.Thr62Pro is detected in ∼1/1,000 individuals of European ancestry, shows incomplete penetrance but a high genetic load in familial clusters of CKD, and is associated with kidney failure in the 100,000 Genomes Project (odds ratio [OR] = 3.99 [1.84 to 8.98]) and the UK Biobank (OR = 4.12 [1.32 to 12.85). Compared with canonical ADTKD mutations, the p.Thr62Pro carriers displayed reduced disease severity, with slower progression of CKD and an intermediate reduction of urinary uromodulin levels, in line with an intermediate trafficking defect in vitro and modest induction of endoplasmic reticulum (ER) stress. Identification of an intermediate-effect UMOD variant completes the spectrum of UMOD-associated kidney diseases and provides insights into the mechanisms of ADTKD and the genetic architecture of CKD.
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Affiliation(s)
- Eric Olinger
- Institute of Physiology, University of Zurich, CH-8057 Zurich, Switzerland
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 3BZ, United Kingdom
| | - Céline Schaeffer
- Molecular Genetics of Renal Disorders, Division of Genetics and Cell Biology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ospedale San Raffaele, Milan, 20132 Italy
| | - Kendrah Kidd
- Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, NC 27101
- Department of Pediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University, 128 08 Prague, Czech Republic
| | - Elhussein A. E. Elhassan
- Division of Nephrology, Beaumont General Hospital, 1297 Dublin, Ireland
- Department of Medicine, Royal College of Surgeons in Ireland, 1297 Dublin, Ireland
| | - Yurong Cheng
- Institute of Genetic Epidemiology, Faculty of Medicine and Medical Center, University of Freiburg, D-79106 Freiburg, Germany
- Faculty of Biology, University of Freiburg, D-79106 Freiburg, Germany
| | - Inès Dufour
- Institute of Physiology, University of Zurich, CH-8057 Zurich, Switzerland
- Division of Nephrology, Cliniques Universitaires Saint-Luc, 1200 Brussels, Belgium
| | - Guglielmo Schiano
- Institute of Physiology, University of Zurich, CH-8057 Zurich, Switzerland
| | - Holly Mabillard
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 3BZ, United Kingdom
- Renal Services, Newcastle Upon Tyne Hospitals National Health Service Trust, Newcastle upon Tyne NE7 7DN, United Kingdom
| | - Elena Pasqualetto
- Molecular Genetics of Renal Disorders, Division of Genetics and Cell Biology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ospedale San Raffaele, Milan, 20132 Italy
| | - Patrick Hofmann
- Institute of Physiology, University of Zurich, CH-8057 Zurich, Switzerland
| | - Daniel G. Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland
| | - Andreas D. Kistler
- Department of Medicine, Cantonal Hospital Frauenfeld, 8501 Frauenfeld, Switzerland
| | - Ian J. Wilson
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE1 3BZ, United Kingdom
| | - Stanislav Kmoch
- Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, NC 27101
- Department of Pediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University, 128 08 Prague, Czech Republic
| | - Laure Raymond
- Genetics Department, Laboratoire Eurofins Biomnis, Lyon, 69007 France
| | - Thomas Robert
- Centre de Néphrologie et Transplantation Rénale, Centre Hospitalier Universitaire (CHU) la Conception, Assistance Publique - Hôpitaux de Marseille (AP-HM), Marseille, 13005 France
- Marseille Medical Genetics, Bioinformatics & Genetics, Unité Mixte de Recherche (UMR)_S910, Aix-Marseille Université, Marseille, 13005 France
| | | | - Kai-Uwe Eckardt
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
- Department of Nephrology and Hypertension, University Hospital Erlangen, Friedrich-Alexander Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Anthony J. Bleyer
- Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, NC 27101
- Department of Pediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University, 128 08 Prague, Czech Republic
| | - Anna Köttgen
- Institute of Genetic Epidemiology, Faculty of Medicine and Medical Center, University of Freiburg, D-79106 Freiburg, Germany
- Centre for Integrative Biological Signalling Studies, University of Freiburg, D-79106 Freiburg, Germany
| | - Peter J. Conlon
- Division of Nephrology, Beaumont General Hospital, 1297 Dublin, Ireland
- Department of Medicine, Royal College of Surgeons in Ireland, 1297 Dublin, Ireland
| | - Michael Wiesener
- Department of Nephrology and Hypertension, University Hospital Erlangen, Friedrich-Alexander Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - John A. Sayer
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 3BZ, United Kingdom
- Renal Services, Newcastle Upon Tyne Hospitals National Health Service Trust, Newcastle upon Tyne NE7 7DN, United Kingdom
- National Institute for Health and Care Research (NIHR) Newcastle Biomedical Research Centre, Newcastle upon Tyne NE4 5PL, United Kingdom
| | - Luca Rampoldi
- Molecular Genetics of Renal Disorders, Division of Genetics and Cell Biology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ospedale San Raffaele, Milan, 20132 Italy
| | - Olivier Devuyst
- Institute of Physiology, University of Zurich, CH-8057 Zurich, Switzerland
- Division of Nephrology, Cliniques Universitaires Saint-Luc, 1200 Brussels, Belgium
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11
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Augustynek B, Gyimesi G, Dernič J, Sallinger M, Albano G, Klesse GJ, Kandasamy P, Grabmayr H, Frischauf I, Fuster DG, Peinelt C, Hediger MA, Bhardwaj R. Discovery of novel gating checkpoints in the Orai1 calcium channel by systematic analysis of constitutively active mutants of its paralogs and orthologs. Cell Calcium 2022; 105:102616. [PMID: 35792401 DOI: 10.1016/j.ceca.2022.102616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/17/2022] [Accepted: 06/20/2022] [Indexed: 11/24/2022]
Abstract
In humans, there are three paralogs of the Orai Ca2+ channel that form the core of the store-operated calcium entry (SOCE) machinery. While the STIM-mediated gating mechanism of Orai channels is still under active investigation, several artificial and natural variants are known to cause constitutive activity of the human Orai1 channel. Surprisingly, little is known about the conservation of the gating checkpoints among the different human Orai paralogs and orthologs in other species. In our work, we show that the mutation corresponding to the activating mutation H134A in transmembrane helix 2 (TM2) of human Orai1 also activates Orai2 and Orai3, likely via a similar mechanism. However, this cross-paralog conservation does not apply to the "ANSGA" nexus mutations in TM4 of human Orai1, which is reported to mimic the STIM1-activated state of the channel. In investigating the mechanistic background of these differences, we identified two positions, H171 and F246 in human Orai1, that are not conserved among paralogs and that seem to be crucial for the channel activation triggered by the "ANSGA" mutations in Orai1. However, mutations of the same residues still allow gating of Orai1 by STIM1, suggesting that the ANSGA mutant of Orai1 may not be a surrogate for the STIM1-activated state of the Orai1 channel. Our results shed new light on these important gating checkpoints and show that the gating mechanism of Orai channels is affected by multiple factors that are not necessarily conserved among orai homologs, such as the TM4-TM3 coupling.
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Affiliation(s)
- Bartłomiej Augustynek
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Gergely Gyimesi
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Jan Dernič
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Matthias Sallinger
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, A-4020 Linz, Austria
| | - Giuseppe Albano
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Gabriel J Klesse
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Palanivel Kandasamy
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Herwig Grabmayr
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, A-4020 Linz, Austria
| | - Irene Frischauf
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, A-4020 Linz, Austria
| | - Daniel G Fuster
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland
| | - Christine Peinelt
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Matthias A Hediger
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland.
| | - Rajesh Bhardwaj
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension and Department of Biomedical Research, Inselspital, University of Bern, Freiburgstrasse 15, CH-3010 Bern, Switzerland; Current address: Signal Transduction Laboratory, National Institute of Environmental Health Sciences, NIH, 111 TW Alexander Drive, NC 27709, USA.
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Verouti SN, Pujol-Giménez J, Bermudez-Lekerika P, Scherler L, Bhardwaj R, Thomas A, Lenglet S, Siegrist M, Hofstetter W, Fuster DG, Hediger MA, Escher G, Vogt B. The Allelic Variant A391T of Metal Ion Transporter ZIP8 (SLC39A8) Leads to Hypotension and Enhanced Insulin Resistance. Front Physiol 2022; 13:912277. [PMID: 35784893 PMCID: PMC9240775 DOI: 10.3389/fphys.2022.912277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/18/2022] [Indexed: 12/12/2022] Open
Abstract
The metal ion transporter ZIP8 (SLC39A8) mediates cellular uptake of vital divalent metal ions. Genome-wide association studies (GWAS) showed that the single-nucleotide polymorphism (SNP) variant A391T (rs13107325) is associated with numerous human traits, including reduced arterial blood pressure, increased body mass index and hyperlipidemia. We analyzed in vitro the transport properties of mutant ZIP8 A391T and investigated in vivo in mice the physiological effects of this polymorphism. In vitro, the intrinsic transport properties of mutant ZIP8 were similar to those of wild type ZIP8, but cellular uptake of zinc, cadmium and iron was attenuated due to reduced ZIP8 plasma membrane expression. We then generated the ZIP8 A393T mice (ZIP8KI) that carry the corresponding polymorphism and characterized their phenotype. We observed lower protein expression in lung and kidney membrane extracts in ZIP8KI mice. The ZIP8KI mice exhibited striking changes in metal ion composition of the tissues, including cobalt, palladium, mercury and platinum. In agreement with GWAS, ZIP8KI mice showed reduced arterial blood pressure. Body weight and plasma lipid composition remained unchanged, although these features were reported to be increased in GWAS. ZIP8KI mice also exhibited remarkable insulin resistance and were protected from elevated blood glucose when challenged by dietary sucrose supplementation. We showed that increased hepatic insulin receptor expression and decreased ZnT8 (slc30a8) metal ion transporter mRNA expression are associated with this phenotypic change. In conclusion, our data reveal that ZIP8 plays an important role in blood pressure regulation and glucose homeostasis.
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Affiliation(s)
- Sophia N. Verouti
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Jonai Pujol-Giménez
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Paola Bermudez-Lekerika
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Laeticia Scherler
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Rajesh Bhardwaj
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, NIH, Durham, NC, United States
| | - Aurélien Thomas
- Forensic Toxicology and Chemistry Unit, CURML, Lausanne University Hospital, Geneva University, Geneva, Switzerland
- Faculty Unit of Toxicology, CURML, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Sébastien Lenglet
- Forensic Toxicology and Chemistry Unit, CURML, Lausanne University Hospital, Geneva University, Geneva, Switzerland
| | - Mark Siegrist
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Willy Hofstetter
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Daniel G. Fuster
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Matthias A. Hediger
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- *Correspondence: Matthias A. Hediger, ; Geneviève Escher, ; Bruno Vogt,
| | - Geneviève Escher
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- *Correspondence: Matthias A. Hediger, ; Geneviève Escher, ; Bruno Vogt,
| | - Bruno Vogt
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- *Correspondence: Matthias A. Hediger, ; Geneviève Escher, ; Bruno Vogt,
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Anderegg MA, Gyimesi G, Ho TM, Hediger MA, Fuster DG. The Less Well-Known Little Brothers: The SLC9B/NHA Sodium Proton Exchanger Subfamily—Structure, Function, Regulation and Potential Drug-Target Approaches. Front Physiol 2022; 13:898508. [PMID: 35694410 PMCID: PMC9174904 DOI: 10.3389/fphys.2022.898508] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/04/2022] [Indexed: 12/15/2022] Open
Abstract
The SLC9 gene family encodes Na+/H+ exchangers (NHEs), a group of membrane transport proteins critically involved in the regulation of cytoplasmic and organellar pH, cell volume, as well as systemic acid-base and volume homeostasis. NHEs of the SLC9A subfamily (NHE 1–9) are well-known for their roles in human physiology and disease. Much less is known about the two members of the SLC9B subfamily, NHA1 and NHA2, which share higher similarity to prokaryotic NHEs than the SLC9A paralogs. NHA2 (also known as SLC9B2) is ubiquitously expressed and has recently been shown to participate in renal blood pressure and electrolyte regulation, insulin secretion and systemic glucose homeostasis. In addition, NHA2 has been proposed to contribute to the pathogenesis of polycystic kidney disease, the most common inherited kidney disease in humans. NHA1 (also known as SLC9B1) is mainly expressed in testis and is important for sperm motility and thus male fertility, but has not been associated with human disease thus far. In this review, we present a summary of the structure, function and regulation of expression of the SLC9B subfamily members, focusing primarily on the better-studied SLC9B paralog, NHA2. Furthermore, we will review the potential of the SLC9B subfamily as drug targets.
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Affiliation(s)
- Manuel A. Anderegg
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- *Correspondence: Manuel A. Anderegg,
| | - Gergely Gyimesi
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Membrane Transport Discovery Lab, Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - Tin Manh Ho
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Matthias A. Hediger
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Membrane Transport Discovery Lab, Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - Daniel G. Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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14
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Sekulic-Jablanovic M, Paproth J, Sgambato C, Albano G, Fuster DG, Bodmer D, Petkovic V. Lack of NHE6 and Inhibition of NKCC1 Associated With Increased Permeability in Blood Labyrinth Barrier-Derived Endothelial Cell Layer. Front Cell Neurosci 2022; 16:862119. [PMID: 35496913 PMCID: PMC9039518 DOI: 10.3389/fncel.2022.862119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 03/17/2022] [Indexed: 12/20/2022] Open
Abstract
Acoustic trauma, autoimmune inner ear disease, and presbycusis feature loss of the integrity of the blood-labyrinth barrier (BLB). Normal BLB function depends on endothelial structural integrity, which is supported and maintained by tight junctions and adherens junctions within the microvascular endothelial layer. When these junctions are disrupted, vascular leakage occurs. Tight junctions and adherens junctions are functionally and structurally linked, but the exact signaling pathways underlying their interaction remain unknown. In addition, solute carriers (SC) are essential for optimal exchange through BLB. Previously, we found that SC family member, the sodium–hydrogen exchanger NHE6, was expressed in all wildtype cochlear tissues, and that Nhe6-knockout mice displayed moderate hearing loss. Moreover, NHE6 depletion affected Trk protein turnover and endosomal signaling. Here, we investigated whether NHE6 might impact BLB integrity. We found that Nhe6-knockout, BLB-derived endothelial cells showed reduced expression of major junctional genes: Tjp1, F11r, Ocln, Cdh5, and Cldn5. Co-culturing BLB-derived endothelial cells with pericytes and/or perivascular resident macrophage-like melanocytes in a transwell system showed that monolayers of Nhe6-knockout BLB-derived cells had lower electrical resistance and higher permeability, compared to wildtype endothelial monolayers. Additionally, another SC, NKCC1, which was previously linked to congenital deafness, was downregulated in our Nhe6-knockout mouse model. Blocking NKCC1 with a NKCC1-specific inhibitor, bumetanide, in wildtype BLB-derived endothelial cells also caused the downregulation of major junctional proteins, particularly Tjp1 and F11r, which encode the zonula occludens and junctional adhesion molecule-1 proteins, respectively. Moreover, bumetanide treatment increased cell permeability. In conclusion, we showed that the lack or inhibition of NHE6 or NKCC1 affected the permeability of endothelial BLB-derived cells. These findings suggested that NHE6 and NKCC1 could serve as potential targets for modifying BLB permeability to facilitate drug delivery across the BLB to the cochlea or to protect the cochlea from ototoxic insults.
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Affiliation(s)
- Marijana Sekulic-Jablanovic
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
- *Correspondence: Marijana Sekulic-Jablanovic,
| | - Jessica Paproth
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Cinzia Sgambato
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Giuseppe Albano
- Inselspital Bern, Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Daniel G. Fuster
- Inselspital Bern, Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Daniel Bodmer
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
- Clinic for Otolaryngology, Head and Neck Surgery, University Hospital Basel, Basel, Switzerland
| | - Vesna Petkovic
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
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15
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Schnyder D, Albano G, Kucharczyk P, Dolder S, Siegrist M, Anderegg M, Pathare G, Hofstetter W, Baron R, Fuster DG. Deletion of the sodium/hydrogen exchanger 6 causes low bone volume in adult mice. Bone 2021; 153:116178. [PMID: 34508879 DOI: 10.1016/j.bone.2021.116178] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 09/04/2021] [Accepted: 09/05/2021] [Indexed: 11/18/2022]
Abstract
The sodium/hydrogen exchanger 6 (NHE6) localizes to recycling endosomes, where it mediates endosomal alkalinization through K+/H+ exchange. Mutations in the SLC9A6 gene encoding NHE6 cause severe X-linked mental retardation, epilepsy, autism and corticobasal degeneration in humans. Patients with SLC9A6 mutations exhibit skeletal malformations, and a previous study suggested a key role of NHE6 in osteoblast-mediated mineralization. The goal of this study was to explore the role of NHE6 in bone homeostasis. To this end, we studied the bone phenotype of NHE6 knock-out mice by microcomputed tomography, quantitative histomorphometry and complementary ex vivo and in vitro studies. We detected NHE6 transcript and protein in both differentiated osteoclasts and mineralizing osteoblasts. In vitro studies with osteoclasts and osteoblasts derived from NHE6 knock-out mice demonstrated normal osteoclast differentiation and osteoblast proliferation without an impairment in mineralization capacity. Microcomputed tomography and bone histomorphometry studies showed a significantly reduced bone volume and trabecular number as well as an increased trabecular space at lumbar vertebrae of 6 months old NHE6 knock-out mice. The bone degradation marker c-terminal telopeptides of type I collagen was unaltered in NHE6 knock-out mice. However, we observed a reduction of the bone formation marker procollagen type 1 N-terminal propeptide, and increased circulating sclerostin levels in NHE6 knock-out mice. Subsequent studies revealed a significant upregulation of sclerostin transcript expression in both primary calvarial cultures and femora derived from NHE6 knock-out mice. Thus, loss of NHE6 in mice causes an increase of sclerostin expression associated with reduced bone formation and low bone volume.
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Affiliation(s)
- Daniela Schnyder
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Giuseppe Albano
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Patrycja Kucharczyk
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Silvia Dolder
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Mark Siegrist
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Manuel Anderegg
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Ganesh Pathare
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Willy Hofstetter
- National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Roland Baron
- Division of Bone and Mineral Research, Harvard Medical School and Harvard School of Dental Medicine, Boston, MA, USA; Department of Oral Medicine, Infection and Immunity, Harvard Medical School and Harvard School of Dental Medicine, Boston, MA, USA
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland.
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16
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Dhayat NA, Schneider L, Popp AW, Lüthi D, Mattmann C, Vogt B, Fuster DG. Predictors of Bone Mineral Density in Kidney Stone Formers. Kidney Int Rep 2021; 7:558-567. [PMID: 35257068 PMCID: PMC8897287 DOI: 10.1016/j.ekir.2021.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/02/2021] [Accepted: 12/06/2021] [Indexed: 11/26/2022] Open
Abstract
Introduction Nephrolithiasis is associated with an increased fracture risk, but predictors of bone mineral density (BMD) in stone formers (SFs) remain poorly defined. Methods We conducted a retrospective analysis in the Bern Kidney Stone Registry (BKSR), an observational cohort of kidney SFs. Inclusion criteria were age ≥18 years and ≥1 past stone episode. Participants with non–calcium (Ca)-containing kidney stones, a history of primary hyperparathyroidism or antiresorptive or anabolic bone treatment were excluded. Multivariable linear regression analyses were used to assess the association of blood and 24-hours urine parameters and stone composition with BMD at the lumbar spine and femoral neck. Results In the analysis, 504 participants were included, mean age was 46 years, and 76% were male. In multivariable analyses, fasting (β: −0.031; P = 0.042), postload (β: −0.059; P = 0.0028) and Δ postload − fasting (β: −0.053; P = 0.0029) urine Ca-to-creatinine ratios after 1 week of a sodium- and Ca- restricted diet and Ca oxalate dihydrate stone content (β: −0.042; P = 0.011) were negatively associated with z scores at the lumbar spine. At the femoral neck, alkaline phosphatase (β: −0.035; P = 0.0034) and parathyroid hormone (PTH) (β: −0.035; P = 0.0026) were negatively associated with z scores, whereas 24-hours urine Ca (β: 0.033; P = 0.0085), magnesium (β: 0.043; P = 3.5 × 10−4), and potassium (β: 0.032; P = 0.012) correlated positively with z scores at the femoral neck. Conclusion Our study reveals distinct predictors of BMD in SFs. Commonly available clinical parameters, such as kidney stone composition results, can be used to identify SFs at risk for low BMD.
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Abstract
Nephrolithiasis is a worldwide problem with increasing prevalence, enormous costs, and significant morbidity. Calcium-containing kidney stones are by far the most common kidney stones encountered in clinical practice. Consequently, hypercalciuria is the greatest risk factor for kidney stone formation. Hypercalciuria can result from enhanced intestinal absorption, increased bone resorption, or altered renal tubular transport. Kidney stone formation is complex and driven by high concentrations of calcium-oxalate or calcium-phosphate in the urine. After discussing the mechanism mediating renal calcium salt precipitation, we review recent discoveries in renal tubular calcium transport from the proximal tubule, thick ascending limb, and distal convolution. Furthermore, we address how calcium is absorbed from the intestine and mobilized from bone. The effect of acidosis on bone calcium resorption and urinary calcium excretion is also considered. Although recent discoveries provide insight into these processes, much remains to be understood in order to provide improved therapies for hypercalciuria and prevent kidney stone formation. Expected final online publication date for the Annual Review of Physiology, Volume 84 is February 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- R T Alexander
- Departments of Physiology and Pediatrics, University of Alberta, Edmonton, Canada; .,Membrane Protein Disease Research Group, University of Alberta, Edmonton, Canada
| | - D G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - H Dimke
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Nephrology, Odense University Hospital, Odense, Denmark
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18
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Fuster DG. [Recurrence prevention of kidney stones - pharmacologic and dietary measures]. Ther Umsch 2021; 78:241-246. [PMID: 34032134 DOI: 10.1024/0040-5930/a001267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recurrence prevention of kidney stones - pharmacologic and dietary measures Abstract. Kidney stone episodes are traumatic events for affected patients and the risk of recurrence is high. Both prevalence and incidence of kidney stone disease are rising globally, and associated cost are gigantic. Hence, effective, well-tolerated and cheap measures for recurrence prevention are of utmost importance. In this article, we summarize the possibilities for the prevention of idiopathic calcium stones and uric acid stones, which together are responsible for the bulk of kidney stone episodes. Formally, preventive measures can be divided into dietary and pharmacologic interventions. In daily practice, frequently both approaches have to be combined to achieve a successful long-term recurrence prevention. The biggest challenge in the recurrence prevention of kidney stones is to achieve a sustained adherence to preventive measures in the affected patients.
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Affiliation(s)
- Daniel G Fuster
- Universitätsklinik für Nephrologie und Hypertonie, Inselspital Bern
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19
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Garrelfs SF, Frishberg Y, Hulton SA, Koren MJ, O'Riordan WD, Cochat P, Deschênes G, Shasha-Lavsky H, Saland JM, Van't Hoff WG, Fuster DG, Magen D, Moochhala SH, Schalk G, Simkova E, Groothoff JW, Sas DJ, Meliambro KA, Lu J, Sweetser MT, Garg PP, Vaishnaw AK, Gansner JM, McGregor TL, Lieske JC. Lumasiran, an RNAi Therapeutic for Primary Hyperoxaluria Type 1. N Engl J Med 2021; 384:1216-1226. [PMID: 33789010 DOI: 10.1056/nejmoa2021712] [Citation(s) in RCA: 227] [Impact Index Per Article: 75.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Primary hyperoxaluria type 1 (PH1) is a rare genetic disease caused by hepatic overproduction of oxalate that leads to kidney stones, nephrocalcinosis, kidney failure, and systemic oxalosis. Lumasiran, an investigational RNA interference (RNAi) therapeutic agent, reduces hepatic oxalate production by targeting glycolate oxidase. METHODS In this double-blind, phase 3 trial, we randomly assigned (in a 2:1 ratio) patients with PH1 who were 6 years of age or older to receive subcutaneous lumasiran or placebo for 6 months (with doses given at baseline and at months 1, 2, 3, and 6). The primary end point was the percent change in 24-hour urinary oxalate excretion from baseline to month 6 (mean percent change across months 3 through 6). Secondary end points included the percent change in the plasma oxalate level from baseline to month 6 (mean percent change across months 3 through 6) and the percentage of patients with 24-hour urinary oxalate excretion no higher than 1.5 times the upper limit of the normal range at month 6. RESULTS A total of 39 patients underwent randomization; 26 were assigned to the lumasiran group and 13 to the placebo group. The least-squares mean difference in the change in 24-hour urinary oxalate excretion (lumasiran minus placebo) was -53.5 percentage points (P<0.001), with a reduction in the lumasiran group of 65.4% and an effect seen as early as month 1. The between-group differences for all hierarchically tested secondary end points were significant. The difference in the percent change in the plasma oxalate level (lumasiran minus placebo) was -39.5 percentage points (P<0.001). In the lumasiran group, 84% of patients had 24-hour urinary oxalate excretion no higher than 1.5 times the upper limit of the normal range at month 6, as compared with 0% in the placebo group (P<0.001). Mild, transient injection-site reactions were reported in 38% of lumasiran-treated patients. CONCLUSIONS Lumasiran reduced urinary oxalate excretion, the cause of progressive kidney failure in PH1. The majority of patients who received lumasiran had normal or near-normal levels after 6 months of treatment. (Funded by Alnylam Pharmaceuticals; ILLUMINATE-A ClinicalTrials.gov number, NCT03681184.).
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Affiliation(s)
- Sander F Garrelfs
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Yaacov Frishberg
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Sally A Hulton
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Michael J Koren
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - William D O'Riordan
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Pierre Cochat
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Georges Deschênes
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Hadas Shasha-Lavsky
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Jeffrey M Saland
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - William G Van't Hoff
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Daniel G Fuster
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Daniella Magen
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Shabbir H Moochhala
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Gesa Schalk
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Eva Simkova
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Jaap W Groothoff
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - David J Sas
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Kristin A Meliambro
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Jiandong Lu
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Marianne T Sweetser
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Pushkal P Garg
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Akshay K Vaishnaw
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - John M Gansner
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - Tracy L McGregor
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
| | - John C Lieske
- From the Department of Pediatric Nephrology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam (S.F.G., J.W.G.); the Division of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem (Y.F.); the Department of Nephrology, Birmingham Women's and Children's Hospital, Birmingham (S.A.H.), and the Department of Paediatric Nephrology, Great Ormond Street Hospital (W.G.H.), and UCL Department of Renal Medicine, Royal Free Hospital (S.H.M.), London - both in the United Kingdom; Jacksonville Center for Clinical Research, Jacksonville, FL (M.J.K.); eStudySite, San Diego, CA (W.D.O.); Center for Rare Renal Diseases and INSERM Pediatric Clinical Investigation Center-Hospices Civils de Lyon and Université de Lyon, Lyon (P.C.), and the Department of Pediatric Nephrology, Hôpital Robert-Debré, Paris (G.D.) - both in France; the Pediatric Nephrology Unit, Galilee Medical Center, Nahariya (H.S.-L.), and the Pediatric Nephrology Institute, Rambam Health Care Campus, Haifa (D.M.) - both in Israel; the Icahn School of Medicine at Mount Sinai, New York (J.M.S., K.A.M.); the Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland (D.G.F.); the University of Bonn, Bonn, Germany (G.S.); Al Jalila Children's Hospital, Dubai, United Arab Emirates (E.S.); the Divisions of Pediatric Nephrology and Hypertension (D.J.S.) and Nephrology and Hypertension (J.C.L.), Mayo Clinic, Rochester, MN; and Alnylam Pharmaceuticals, Cambridge, MA (J.L., M.T.S., P.P.G., A.K.V., J.M.G., T.L.M.)
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Affiliation(s)
- Simeon Schietzel
- Division of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
| | - Matthias B Moor
- Division of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Division of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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21
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Verouti SN, Lambert D, Mathis D, Pathare G, Escher G, Vogt B, Fuster DG. Solute carrier SLC16A12 is critical for creatine and guanidinoacetate handling in the kidney. Am J Physiol Renal Physiol 2021; 320:F351-F358. [PMID: 33459166 DOI: 10.1152/ajprenal.00475.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 01/07/2021] [Indexed: 11/22/2022] Open
Abstract
A heterozygous mutation (c.643C.A; p.Q215X) in the creatine transporter SLC16A12 has been proposed to cause a syndrome with juvenile cataracts, microcornea, and glucosuria in humans. To further explore the role of SLC16A12 in renal physiology and decipher the mechanism underlying the phenotype of humans with the SLC16A12 mutation, we studied Slc16a12 knockout (KO) rats. Slc16a12 KO rats had lower plasma levels and increased absolute and fractional urinary excretion of creatine and its precursor guanidinoacetate (GAA). Slc16a12 KO rats displayed lower plasma and urinary creatinine levels, but the glomerular filtration rate was normal. The phenotype of heterozygous rats was indistinguishable from wild-type (WT) rats. Renal artery to vein (RAV) concentration differences in WT rats were negative for GAA and positive for creatinine. However, RAV differences for GAA were similar in Slc16a12 KO rats, indicating incomplete compensation of urinary GAA losses by renal GAA synthesis. Together, our results reveal that Slc16a12 in the basolateral membrane of the proximal tubule is critical for the reabsorption of creatine and GAA. Our data suggest a dominant-negative mechanism underlying the phenotype of humans affected by the heterozygous SLC16A12 mutation. Furthermore, in the absence of Slc16a12, urinary losses of GAA are not adequately compensated by increased tubular synthesis, likely caused by feedback inhibition of the rate-limiting enzyme l-arginine:glycine amidinotransferase by creatine in proximal tubular cells.NEW & NOTEWORTHY SLC16A12 is a recently identified creatine transporter of unknown physiological function. A heterozygous mutation in the human SLC16A12 gene causes juvenile cataracts and reduced plasma guanidinoacetate (GAA) levels with an increased fractional urinary excretion of GAA. Our study with transgenic SLC16A12-deficient rats reveals that SLC16A12 is critical for tubular reabsorption of creatine and GAA in the kidney. Our data furthermore indicate a dominant-negative mechanism underlying the phenotype of humans affected by the heterozygous SLC16A12 mutation.
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Affiliation(s)
- Sophia N Verouti
- Department for BioMedical Research, University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Delphine Lambert
- Department for BioMedical Research, University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Déborah Mathis
- Laboratory Clinical Chemistry and Biochemistry, Kinderspital Zurich, Zurich, Switzerland
| | - Ganesh Pathare
- Department for BioMedical Research, University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Geneviève Escher
- Department for BioMedical Research, University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Bruno Vogt
- Department for BioMedical Research, University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Department for BioMedical Research, University of Bern, Bern, Switzerland
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
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22
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Fuster DG, Morard GA, Schneider L, Mattmann C, Lüthi D, Vogt B, Dhayat NA. Association of urinary sex steroid hormones with urinary calcium, oxalate and citrate excretion in kidney stone formers. Nephrol Dial Transplant 2020; 37:335-348. [PMID: 33295624 DOI: 10.1093/ndt/gfaa360] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Sex-specific differences in nephrolithiasis with respect to both distribution of prevalence and stone composition are widely described and may be influenced by sex hormones. METHODS We conducted a cross-sectional analysis of the relationship between 24-hour urinary sex hormone metabolites measured by gas chromatography-mass spectrometry with urinary calcium, oxalate and citrate excretion in a cohort of 628 kidney stone formers from a tertiary care hospital in Switzerland, taking demographic characteristics, kidney function and dietary factors into account. RESULTS We observed a positive association of urinary calcium with urinary testosterone and 17β-estradiol. Positive associations of urinary calcium with dehydroepiandrosterone, 5α-DH-testosterone, etiocholanolone, androsterone, and estriol were modified by net gastrointestinal alkali absorption or urinary sulfate excretion. As the only sex hormone, dehydroepiandrosterone was inversely associated with urinary oxalate excretion in adjusted analyses. Urinary citrate correlated positively with urinary testosterone. Associations of urinary citrate with urinary androsterone, 17β-estradiol and estriol were modified by urinary sulfate or sodium, or by sex. CONCLUSIONS Urinary androgens and estrogens are significantly associated with urinary calcium and citrate excretion, and associations are in part modified by diet. Our data furthermore reveal dehydroepiandrosterone as a novel factor associated with urinary oxalate excretion in humans.
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Affiliation(s)
- Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Gaétan A Morard
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Lisa Schneider
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Cedric Mattmann
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - David Lüthi
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Nasser A Dhayat
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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23
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Bargagli M, Dhayat NA, Anderegg M, Semmo M, Huynh-Do U, Vogt B, Ferraro PM, Fuster DG. Urinary Lithogenic Risk Profile in ADPKD Patients Treated with Tolvaptan. Clin J Am Soc Nephrol 2020; 15:1007-1014. [PMID: 32527945 PMCID: PMC7341771 DOI: 10.2215/cjn.13861119] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 04/24/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND OBJECTIVES Nephrolithiasis is a common health problem in autosomal dominant polycystic kidney disease (ADPKD) and significantly contributes to patient morbidity. Recently, Tolvaptan has been introduced for the treatment of ADPKD, but whether it is associated with alterations of the urinary lithogenic risk profile remains unknown. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We conducted an analysis of participants enrolled in the Bern ADPKD registry, a prospective observational cohort study. Twenty-four-hour urine analyses were performed at baseline and then at yearly follow-ups. Relative supersaturation ratios for calcium oxalate, brushite, and uric acid were calculated with the program EQUIL2. Unadjusted and multivariable mixed-effects linear regression models, adjusted for age, sex, body mass index, eGFR, net acid excretion, and height-adjusted total kidney volume, were used to assess the association of Tolvaptan with urinary parameters relevant for kidney stone formation. The maximum individual follow-up time was 3 years, median follow-up time 1.9 years, and cumulative follow-up time 169 years. RESULTS In total, 125 participants (38 with and 87 without Tolvaptan treatment) were included in the analysis. In multivariable analysis, Tolvaptan treatment was associated [adjusted estimate of the difference between Tolvaptan and no Tolvaptan; 95% confidence interval (CI)] with lower urine relative supersaturation ratios for calcium oxalate (-0.56; 95% CI, -0.82 to -0.3; P<0.001), brushite (-0.33; 95% CI, -0.54 to -0.11; P=0.004), and uric acid (-0.62; 95% CI, -0.88 to -0.37; P<0.001), and with higher urine citrate in mmol/mmol creatinine per day (0.25; 95% CI, 0.05 to 0.46; P=0.02) and calcium in mmol/mmol creatinine per day (0.31; 95% CI, 0.09 to 0.53; P=0.006) excretion. In addition, Tolvaptan treatment was associated with lower net acid excretion in mEq/mmol creatinine per day (-0.54; 95% CI, -0.90 to -0.17; P=0.004) and higher net gastrointestinal alkali absorption in mEq/mmol creatinine per day (0.57; 95% CI, 0.26 to 0.88; P<0.001). CONCLUSIONS Tolvaptan treatment is associated with a significantly improved urinary lithogenic risk profile in patients with ADPKD.
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Affiliation(s)
- Matteo Bargagli
- U.O.C. Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.,Università Cattolica del Sacro Cuore, Rome, Italy
| | - Nasser A Dhayat
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Manuel Anderegg
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Mariam Semmo
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Uyen Huynh-Do
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Pietro Manuel Ferraro
- U.O.C. Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.,Università Cattolica del Sacro Cuore, Rome, Italy
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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Olinger E, Hofmann P, Kidd K, Dufour I, Belge H, Schaeffer C, Kipp A, Bonny O, Deltas C, Demoulin N, Fehr T, Fuster DG, Gale DP, Goffin E, Hodaňová K, Huynh-Do U, Kistler A, Morelle J, Papagregoriou G, Pirson Y, Sandford R, Sayer JA, Torra R, Venzin C, Venzin R, Vogt B, Živná M, Greka A, Dahan K, Rampoldi L, Kmoch S, Bleyer AJ, Devuyst O. Clinical and genetic spectra of autosomal dominant tubulointerstitial kidney disease due to mutations in UMOD and MUC1. Kidney Int 2020; 98:717-731. [PMID: 32450155 DOI: 10.1016/j.kint.2020.04.038] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 03/23/2020] [Accepted: 04/02/2020] [Indexed: 12/12/2022]
Abstract
Autosomal dominant tubulointerstitial kidney disease (ADTKD) is an increasingly recognized cause of end-stage kidney disease, primarily due to mutations in UMOD and MUC1. The lack of clinical recognition and the small size of cohorts have slowed the understanding of disease ontology and development of diagnostic algorithms. We analyzed two registries from Europe and the United States to define genetic and clinical characteristics of ADTKD-UMOD and ADTKD-MUC1 and develop a practical score to guide genetic testing. Our study encompassed 726 patients from 585 families with a presumptive diagnosis of ADTKD along with clinical, biochemical, genetic and radiologic data. Collectively, 106 different UMOD mutations were detected in 216/562 (38.4%) of families with ADTKD (303 patients), and 4 different MUC1 mutations in 72/205 (35.1%) of the families that are UMOD-negative (83 patients). The median kidney survival was significantly shorter in patients with ADTKD-MUC1 compared to ADTKD-UMOD (46 vs. 54 years, respectively), whereas the median gout-free survival was dramatically reduced in patients with ADTKD-UMOD compared to ADTKD-MUC1 (30 vs. 67 years, respectively). In contrast to patients with ADTKD-UMOD, patients with ADTKD-MUC1 had normal urinary excretion of uromodulin and distribution of uromodulin in tubular cells. A diagnostic algorithm based on a simple score coupled with urinary uromodulin measurements separated patients with ADTKD-UMOD from those with ADTKD-MUC1 with a sensitivity of 94.1%, a specificity of 74.3% and a positive predictive value of 84.2% for a UMOD mutation. Thus, ADTKD-UMOD is more frequently diagnosed than ADTKD-MUC1, ADTKD subtypes present with distinct clinical features, and a simple score coupled with urine uromodulin measurements may help prioritizing genetic testing.
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Affiliation(s)
- Eric Olinger
- Institute of Physiology, University of Zurich, Zurich, Switzerland; Department of Nephrology and Hypertension, Inselspital Bern University Hospital, Bern, Switzerland; Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.
| | - Patrick Hofmann
- Institute of Physiology, University of Zurich, Zurich, Switzerland; Department of Internal Medicine, Hospital Uster, Uster, Switzerland
| | - Kendrah Kidd
- Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA; Research Unit for Rare Diseases, Department of Pediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Inès Dufour
- Institute of Physiology, University of Zurich, Zurich, Switzerland; Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - Hendrica Belge
- Center for Human Genetics, Institute of Pathology and Genetics, Gosselies, Belgium
| | - Céline Schaeffer
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
| | - Anne Kipp
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Olivier Bonny
- Service of Nephrology, Lausanne University Hospital, Lausanne, Switzerland
| | - Constantinos Deltas
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Nathalie Demoulin
- Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium; Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium
| | - Thomas Fehr
- Institute of Physiology, University of Zurich, Zurich, Switzerland; Department of Internal Medicine, Cantonal Hospital Graubuenden, Chur, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital Bern University Hospital, Bern, Switzerland
| | - Daniel P Gale
- Department of Nephrology, University College of London, London, UK
| | - Eric Goffin
- Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium; Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium
| | - Kateřina Hodaňová
- Research Unit for Rare Diseases, Department of Pediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Uyen Huynh-Do
- Department of Nephrology and Hypertension, Inselspital Bern University Hospital, Bern, Switzerland
| | - Andreas Kistler
- Department of Internal Medicine, Cantonal Hospital Frauenfeld, Frauenfeld, Switzerland
| | - Johann Morelle
- Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium; Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium
| | - Gregory Papagregoriou
- Molecular Medicine Research Center, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Yves Pirson
- Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - Richard Sandford
- Department of Medical Genetics, Cambridge Biomedical Campus, Cambridge, UK
| | - John A Sayer
- Renal Services, Newcastle upon Tyne Hospitals National Health Service Trust, Newcastle upon Tyne, UK; Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Roser Torra
- Inherited Renal Disorders, Nephrology Department, Fundació Puigvert, Spanish Renal Research Network (REDinREN), Instituto de Investigaciones Biomédicas Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Christina Venzin
- Division of Nephrology, Department of Internal Medicine, Hospital Davos, Davos, Switzerland
| | - Reto Venzin
- Division of Nephrology, Department of Internal Medicine, Cantonal Hospital Graubuenden, Chur, Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital Bern University Hospital, Bern, Switzerland
| | - Martina Živná
- Research Unit for Rare Diseases, Department of Pediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Anna Greka
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA; Broad Institute of MIT and Harvard, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Karin Dahan
- Center for Human Genetics, Institute of Pathology and Genetics, Gosselies, Belgium
| | - Luca Rampoldi
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
| | - Stanislav Kmoch
- Research Unit for Rare Diseases, Department of Pediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Anthony J Bleyer
- Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA; Research Unit for Rare Diseases, Department of Pediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic.
| | - Olivier Devuyst
- Institute of Physiology, University of Zurich, Zurich, Switzerland; Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium.
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Dhayat NA, Pruijm M, Ponte B, Ackermann D, Leichtle AB, Devuyst O, Ehret G, Guessous I, Pechère-Bertschi A, Pastor J, Martin PY, Burnier M, Fiedler GM, Vogt B, Moe OW, Bochud M, Fuster DG. Parathyroid Hormone and Plasma Phosphate Are Predictors of Soluble α-Klotho Levels in Adults of European Descent. J Clin Endocrinol Metab 2020; 105:5644279. [PMID: 31774122 PMCID: PMC7341480 DOI: 10.1210/clinem/dgz232] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 11/26/2019] [Indexed: 01/08/2023]
Abstract
CONTEXT α-klotho is an integral membrane protein that serves as a coreceptor for fibroblast growth factor 23 (FGF23) in conjunction with cognate fibroblast growth factor receptors. Proteolytic cleavage sheds the ectodomain of α-klotho (soluble α-klotho) as an endocrine substance into blood, urine, and cerebrospinal fluid. OBJECTIVE To study the relationship of soluble α-klotho to mineral metabolism in the general population with mainly preserved kidney function. DESIGN Cross-sectional analysis of the associations between soluble α-klotho with laboratory markers of markers of mineral metabolism in a population-based cohort. SETTING Three centers in Switzerland including 1128 participants. MEASURES Soluble full-length α-klotho levels by a specific immunoassay and markers of mineral metabolism. RESULTS The median serum level of soluble α-klotho was 15.0 pmol/L. Multivariable analyses using α-klotho as the outcome variable revealed a sex-by-PTH interaction: In men, PTH was positively associated with α-klotho levels, whereas this association was negative in women. Plasma phosphate associated with soluble α-klotho levels in an age-dependent manner, changing from a positive association in young adults gradually to a negative association in the elderly. The decline of 1,25 (OH)2 vitamin D3 levels in parallel to the gradual impairment of kidney function was greatly attenuated in the setting of high circulating soluble α-klotho levels. CONCLUSIONS Soluble α-klotho level is associated with plasma phosphate in an age-dependent manner and with PTH in a sex-dependent manner. Furthermore, our data reveal soluble α-klotho as a modulator of 1,25 (OH)2 vitamin D3 levels in individuals with preserved renal function.
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Affiliation(s)
- Nasser A Dhayat
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Menno Pruijm
- Nephrology Service, Lausanne University Hospital, Lausanne, Switzerland
| | - Belen Ponte
- Nephrology Service, Department of Specialties of Internal Medicine, Geneva University Hospital, Geneva, Switzerland
| | - Daniel Ackermann
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Alexander Benedikt Leichtle
- Department of Laboratory Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Insel Data Science Center, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Olivier Devuyst
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Georg Ehret
- Cardiology Service, Department of Specialties of Internal Medicine, Geneva University Hospital, Geneva, Switzerland
| | - Idris Guessous
- Division of Primary Care Medicine, Geneva University Hospital, Geneva, Switzerland
| | - Antoinette Pechère-Bertschi
- Endocrinology Service, Department of Specialties of Internal Medicine, Geneva University Hospital, Geneva, Switzerland
| | - Johanne Pastor
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, Department of Physiology and Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Pierre-Yves Martin
- Nephrology Service, Department of Specialties of Internal Medicine, Geneva University Hospital, Geneva, Switzerland
| | - Michel Burnier
- Nephrology Service, Lausanne University Hospital, Lausanne, Switzerland
| | - Georg-Martin Fiedler
- Department of Laboratory Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Orson W Moe
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, Department of Physiology and Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Murielle Bochud
- Center for Primary Care and Public Health (Unisanté), University of Lausanne, Lausanne, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Correspondence and Reprint Requests: Daniel G. Fuster, Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland. E-mail:
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26
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Gyimesi G, Albano G, Fuster DG, Hediger MA, Pujol-Giménez J. Correction: Unraveling the structural elements of pH sensitivity and substrate binding in the human zinc transporter SLC39A2 (ZIP2). J Biol Chem 2020; 295:4369. [DOI: 10.1074/jbc.aac120.013245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Kucharava K, Brand Y, Albano G, Sekulic-Jablanovic M, Glutz A, Xian X, Herz J, Bodmer D, Fuster DG, Petkovic V. Sodium-hydrogen exchanger 6 (NHE6) deficiency leads to hearing loss, via reduced endosomal signalling through the BDNF/Trk pathway. Sci Rep 2020; 10:3609. [PMID: 32107410 PMCID: PMC7046661 DOI: 10.1038/s41598-020-60262-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 02/07/2020] [Indexed: 01/03/2023] Open
Abstract
Acid-base homeostasis is critical for normal growth, development, and hearing function. The sodium-hydrogen exchanger 6 (NHE6), a protein mainly expressed in early and recycling endosomes, plays an important role in regulating organellar pH. Mutations in NHE6 cause complex, slowly progressive neurodegeneration. Little is known about NHE6 function in the mouse cochlea. Here, we found that all NHE isoforms were expressed in wild-type (WT) mouse cochlea. Nhe6 knockout (KO) mice showed significant hearing loss compared to WT littermates. Immunohistochemistry in WT mouse cochlea showed that Nhe6 was localized in the organ of Corti (OC), spiral ganglion (SG), stria vascularis (SV), and afferent nerve fibres. The middle and the inner ears of WT and Nhe6 KO mice were not different morphologically. Given the putative role of NHE6 in early endosomal function, we examined Rab GTPase expression in early and late endosomes. We found no change in Rab5, significantly lower Rab7, and higher Rab11 levels in the Nhe6 KO OC, compared to WT littermates. Because Rabs mediate TrkB endosomal signalling, we evaluated TrkB phosphorylation in the OCs of both strains. Nhe6 KO mice showed significant reductions in TrkB and Akt phosphorylation in the OC. In addition, we examined genes used as markers of SG type I (Slc17a7, Calb1, Pou4f1, Cal2) and type II neurons (Prph, Plk5, Cacna1g). We found that all marker gene expression levels were significantly elevated in the SG of Nhe6 KO mice, compared to WT littermates. Anti-neurofilament factor staining showed axon loss in the cochlear nerves of Nhe6 KO mice compared to WT mice. These findings indicated that BDNF/TrkB signalling was disrupted in the OC of Nhe6 KO mice, probably due to TrkB reduction, caused by over acidification in the absence of NHE6. Thus, our findings demonstrated that NHEs play important roles in normal hearing in the mammalian cochlea.
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Affiliation(s)
- Krystsina Kucharava
- Department of Biomedicine, and Clinic for Otolaryngology, Head and Neck Surgery, Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Yves Brand
- Clinic for Otolaryngology, Head and Neck Surgery, Kantonsspital Graubünden, Chur, 7000, Switzerland
| | - Giuseppe Albano
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, and NCCR Transcure, University of Bern, Bern, Switzerland
| | - Marijana Sekulic-Jablanovic
- Department of Biomedicine, and Clinic for Otolaryngology, Head and Neck Surgery, Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Andrea Glutz
- Department of Biomedicine, and Clinic for Otolaryngology, Head and Neck Surgery, Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Xunde Xian
- Center for Translational Neurodegeneration Research, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Joachim Herz
- Center for Translational Neurodegeneration Research, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Daniel Bodmer
- Department of Biomedicine, and Clinic for Otolaryngology, Head and Neck Surgery, Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, and NCCR Transcure, University of Bern, Bern, Switzerland
| | - Vesna Petkovic
- Department of Biomedicine, and Clinic for Otolaryngology, Head and Neck Surgery, Hospital Basel, University of Basel, Basel, 4031, Switzerland.
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28
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Gyimesi G, Albano G, Fuster DG, Hediger MA, Pujol-Giménez J. Unraveling the structural elements of pH sensitivity and substrate binding in the human zinc transporter SLC39A2 (ZIP2). J Biol Chem 2019; 294:8046-8063. [PMID: 30914478 PMCID: PMC6527156 DOI: 10.1074/jbc.ra118.006113] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 03/22/2019] [Indexed: 12/20/2022] Open
Abstract
The transport and ion-coupling mechanisms of ZIP transporters remain largely uncharacterized. Previous work in our laboratory has revealed that the solute carrier family 39 member A2 (SLC39A2/ZIP2) increases its substrate transport rate in the presence of extracellular H+. Here, we used a combination of in silico and in vitro techniques involving structural modeling, mutagenesis, and functional characterization in HEK293 cells to identify amino acid residues potentially relevant for both the ZIP2–H+ interaction and substrate binding. Our ZIP2 models revealed a cluster of charged residues close to the substrate–translocation pore. Interestingly, the H63A substitution completely abrogated pH sensitivity, and substitutions of Glu-67 and Phe-269 altered the pH and voltage modulation of transport. In contrast, substitution of Glu-106, which might be part of a dimerization interface, altered pH but not voltage modulation. Substitution of Phe-269, located close to the substrate-binding site, also affected substrate selectivity. These findings were supported by an additional model of ZIP2 that was based on the structure of a prokaryotic homolog, Bordetella bronchiseptica ZrT/Irt-like protein (bbZIP), and in silico pKa calculations. We also found that residues Glu-179, His-175, His-202, and Glu-276 are directly involved in the coordination of the substrate metal ion. We noted that, unlike bbZIP, human ZIP2 is predicted to harbor a single divalent metal-binding site, with the charged side chain of Lys-203 replacing the second bound ion. Our results provide the first structural evidence for the previously observed pH and voltage modulation of ZIP2-mediated metal transport, identify the substrate-binding site, and suggest a structure-based transport mechanism for the ZIP2 transporter.
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Affiliation(s)
- Gergely Gyimesi
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland; National Center of Competence in Research, NCCR TransCure, Bühlstrasse 28, 3012 Bern, Switzerland; Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 18, 3010 Bern, Switzerland
| | - Giuseppe Albano
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland; National Center of Competence in Research, NCCR TransCure, Bühlstrasse 28, 3012 Bern, Switzerland; Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 18, 3010 Bern, Switzerland
| | - Daniel G Fuster
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland; National Center of Competence in Research, NCCR TransCure, Bühlstrasse 28, 3012 Bern, Switzerland; Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 18, 3010 Bern, Switzerland
| | - Matthias A Hediger
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland; National Center of Competence in Research, NCCR TransCure, Bühlstrasse 28, 3012 Bern, Switzerland; Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 18, 3010 Bern, Switzerland.
| | - Jonai Pujol-Giménez
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland; National Center of Competence in Research, NCCR TransCure, Bühlstrasse 28, 3012 Bern, Switzerland; Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 18, 3010 Bern, Switzerland.
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29
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Ferraro PM, Arrabal-Polo MÁ, Capasso G, Croppi E, Cupisti A, Ernandez T, Fuster DG, Galan JA, Grases F, Hoorn EJ, Knauf F, Letavernier E, Mohebbi N, Moochhala S, Petkova K, Pozdzik A, Sayer J, Seitz C, Strazzullo P, Trinchieri A, Vezzoli G, Vitale C, Vogt L, Unwin RJ, Bonny O, Gambaro G. A preliminary survey of practice patterns across several European kidney stone centers and a call for action in developing shared practice. Urolithiasis 2019; 47:219-224. [PMID: 30848320 DOI: 10.1007/s00240-019-01119-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 02/08/2019] [Indexed: 11/24/2022]
Abstract
Currently an evidence-based approach to nephrolithiasis is hampered by a lack of randomized controlled trials. Thus, there is a need for common platforms for data sharing and recruitment of patients to interventional studies. A first step in achieving this objective would be to share practice methods and protocols for subsequent standardization in what is still a heterogeneous clinical field. Here, we present the results of a pilot survey performed across 24 European clinical kidney stone centers. The survey was distributed by a voluntary online questionnaire circulated between June 2017 and January 2018. About 46% of centers reported seeing on average 20 or more patients per month. Only 21% adopted any formal referral criteria. Centers were relatively heterogeneous in respect of the definition of an incident stone event. The majority (71%) adopted a formal follow-up scheme; of these, 65% included a follow-up visit at 3 and 12 months, and 41% more than 12 months. In 79% of centers some kind of imaging was performed systematically. 75% of all centers performed laboratory analyses on blood samples at baseline and during follow-up. All centers performed laboratory analyses on 24-h urine samples, the majority (96%) at baseline and during follow-up. There was good correspondence across centers for analyses performed on 24-h urine samples, although the methods of 24-h urine collection and analysis were relatively heterogeneous. Our survey among 24 European stone centers highlights areas of homogeneity and heterogeneity that will be investigated further. Our aim is the creation of a European network of stone centers sharing practice patterns and hosting a common database for research and guidance in clinical care.
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Affiliation(s)
- Pietro Manuel Ferraro
- U.O.C. Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Via G. Moscati 31, 00168, Roma, Italy. .,Università Cattolica del Sacro Cuore, Roma, Italy.
| | - Miguel Ángel Arrabal-Polo
- Lithotripsy and Endourology Unit, Department of Urology, San Cecilio University Hospital, Granada, Spain
| | - Giovambattista Capasso
- Division of Nephrology, Department of Cardio-thoracic and Respiratory Sciences, University of Campania "Luigi Vanvitelli", Naples, Italy
| | | | - Adamasco Cupisti
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Thomas Ernandez
- Service of Nephrology, University hospital of Geneva, Geneva, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Juan Antonio Galan
- Urolithiasis and Endourology Unit, General University Hospital, Alicante, Spain
| | - Felix Grases
- Laboratory of Renal Lithiasis Research, University Institute of Health Sciences Research, Palma de Mallorca, Spain
| | - Ewout J Hoorn
- Department of Internal Medicine, Division of Nephrology and Transplantation, Erasmus medical center, Rotterdam, The Netherlands
| | - Felix Knauf
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - Nilufar Mohebbi
- Division of Nephrology, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland
| | | | - Kremena Petkova
- Department of Urology and Nephrology, Military Medical Academy, Sofia, Bulgaria
| | - Agnieszka Pozdzik
- Nephrology Clinic, Hôpital Brugmann, Kidney Stones Clinic, Centre Hospitalier Universitaire, Université Libre de Bruxelles, Brussels, Belgium
| | - John Sayer
- Newcastle upon Tyne Hospitals NHS Foundation Trust, NE7 7DN, Newcastle, UK.,Institute of Genetic Medicine, Newcastle University, Central Parkway, NE1 3BZ, Newcastle, UK.,NIHR Newcastle Biomedical Research Centre, Campus for Ageing and Vitality, Newcastle, NE4 5PL, UK
| | - Christian Seitz
- Department of Urology, Medical University of Vienna, Währinger Gurtel 18-20 in, 1090, Vienna, Austria
| | - Pasquale Strazzullo
- Department of Clinical Medicine and Surgery, Federico II University of Naples, Naples, Italy
| | | | - Giuseppe Vezzoli
- Nephrology and Dialysis Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Corrado Vitale
- Nephrology and Dialysis Unit, AO Ordine Mauriziano, Torino, Italy
| | - Liffert Vogt
- Amsterdam Cardiovascular Sciences, Dept of Internal Medicine, section Nephrology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Robert J Unwin
- Kidney and Urology Centre, Royal Free Hospital, London, UK
| | - Olivier Bonny
- Service of Nephrology, Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Giovanni Gambaro
- U.O.C. Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Via G. Moscati 31, 00168, Roma, Italy.,Università Cattolica del Sacro Cuore, Roma, Italy
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30
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Dhayat NA, Faller N, Bonny O, Mohebbi N, Ritter A, Pellegrini L, Bedino G, Schönholzer C, Venzin RM, Hüsler C, Koneth I, Del Giorno R, Gabutti L, Amico P, Mayr M, Odermatt U, Buchkremer F, Ernandez T, Stoermann-Chopard C, Teta D, Rintelen F, Roumet M, Irincheeva I, Trelle S, Tamò L, Roth B, Vogt B, Fuster DG. Efficacy of standard and low dose hydrochlorothiazide in the recurrence prevention of calcium nephrolithiasis (NOSTONE trial): protocol for a randomized double-blind placebo-controlled trial. BMC Nephrol 2018; 19:349. [PMID: 30526528 PMCID: PMC6288917 DOI: 10.1186/s12882-018-1144-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 11/20/2018] [Indexed: 11/13/2022] Open
Abstract
Background Nephrolithiasis is a global healthcare problem with a current lifetime risk of 18.8% in men and 9.4% in women. Given the high cost of medical treatments and surgical interventions as well as the morbidity related to symptomatic stone disease, medical prophylaxis for stone recurrence is an attractive approach. Thiazide diuretics have been the cornerstone of pharmacologic metaphylaxis for more than 40 years. However, evidence for benefits and harms of thiazides in the prevention of calcium containing kidney stones in general remains unclear. In addition, the efficacy of the currently employed low dose thiazide regimens to prevent stone recurrence is not known. Methods The NOSTONE trial is an investigator-initiated 3-year prospective, multicenter, double-blind, placebo-controlled trial to assess the efficacy of standard and low dose hydrochlorothiazide treatment in the recurrence prevention of calcium containing kidney stones. We plan to include 416 adult (≥ 18 years) patients with recurrent (≥ 2 stone episodes in the last 10 years) calcium containing kidney stones (containing ≥50% of calcium oxalate, calcium phosphate or a mixture of both). Patients will be randomly allocated to 50 mg or 25 mg or 12.5 mg hydrochlorothiazide or placebo. The primary outcome will be incidence of stone recurrence (a composite of symptomatic or radiologic recurrence). Secondary outcomes will be individual components of the composite primary outcome, safety and tolerability of hydrochlorothiazide treatment, changes in urinary biochemistry elicited by hydrochlorothiazide treatment and impact of baseline disease severity, biochemical abnormalities and stone composition on treatment response. Discussion The NOSTONE study will provide long-sought information on the efficacy of hydrochlorothiazide in the recurrence prevention of calcium containing kidney stones. Strengths of the study include the randomized, double-blind and placebo-controlled design, the large amount of patients studied, the employment of high sensitivity and high specificity imaging and the exclusive public funding support. Trial registration ClinicalTrials.gov, NCT03057431. Registered on February 20 2017.
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Affiliation(s)
- Nasser A Dhayat
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Nicolas Faller
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Olivier Bonny
- Department of Nephrology, CHUV, University Hospital Lausanne, University of Lausanne, Lausanne, Switzerland
| | - Nilufar Mohebbi
- Department of Nephrology, University Hospital Zurich, Zürich, Switzerland
| | - Alexander Ritter
- Department of Nephrology, University Hospital Zurich, Zürich, Switzerland
| | - Lisa Pellegrini
- Department of Nephrology, Regional Hospital Lugano, Lugano, Switzerland
| | - Giulia Bedino
- Department of Nephrology, Regional Hospital Lugano, Lugano, Switzerland
| | - Carlo Schönholzer
- Department of Nephrology, Regional Hospital Lugano, Lugano, Switzerland
| | - Reto M Venzin
- Department of Nephrology, Cantonal Hospital Chur, Chur, Switzerland
| | - Carina Hüsler
- Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | - Irene Koneth
- Department of Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | - Rosaria Del Giorno
- Department of Nephrology, Regional Hospital Bellinzona, Bellinzona, Switzerland
| | - Luca Gabutti
- Department of Nephrology, Regional Hospital Bellinzona, Bellinzona, Switzerland
| | - Patrizia Amico
- Medical Outpatient Department, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Michael Mayr
- Medical Outpatient Department, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Urs Odermatt
- Department of Nephrology, Cantonal Hospital Luzern, Luzern, Switzerland
| | - Florian Buchkremer
- Division of Nephrology, Dialysis and Transplantation, Cantonal Hospital Aarau, Aarau, Switzerland
| | - Thomas Ernandez
- Department of Nephrology, HUG, University Hospital Geneva, University of Geneva, Geneva, Switzerland
| | | | - Daniel Teta
- Service de Nephrology, Centre Hospitalier du Valais Romand (CHVR), Sion, Switzerland
| | - Felix Rintelen
- Clinical Trials Unit, University of Bern, Bern, Switzerland
| | - Marie Roumet
- Clinical Trials Unit, University of Bern, Bern, Switzerland
| | | | - Sven Trelle
- Clinical Trials Unit, University of Bern, Bern, Switzerland
| | - Luca Tamò
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Clinical Trials Unit, University of Bern, Bern, Switzerland
| | - Beat Roth
- Department of Urology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
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Alexander RT, McArthur E, Jandoc R, Welk B, Fuster DG, Garg AX, Quinn RR. Thiazide Diuretic Dose and Risk of Kidney Stones in Older Adults: A Retrospective Cohort Study. Can J Kidney Health Dis 2018; 5:2054358118787480. [PMID: 30034815 PMCID: PMC6048667 DOI: 10.1177/2054358118787480] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 05/17/2018] [Indexed: 11/17/2022] Open
Abstract
Background Thiazide diuretics are commonly prescribed to prevent kidney stones. However, it is unclear whether higher doses confer greater benefit. Objective To determine whether lower doses of thiazide diuretics confer a similar protective effect against kidney stone events as higher doses. Design Population-based cohort study. Setting Linked health administrative databases in Ontario, Canada. Patients Older adults newly prescribed a thiazide diuretic between 2003 and 2014 were separated into 2 groups based on daily dose: low dose (⩽12.5 mg hydrochlorothiazide/chlorthalidone, or ⩽1.25 mg indapamide) or high dose. Measurements The primary outcome was time to a kidney stone event, using diagnosis and procedure codes. A secondary outcome was kidney stone surgery. Methods An association between thiazide diuretic dose and a kidney stone event was estimated using Cox proportional hazards regression. Results A total of 536 of 105 239 patients (0.51%) experienced a kidney stone event. We did not detect a difference in kidney stone risk in the high-dose relative to the low-dose group (adjusted hazard ratio, 1.10; 95% confidence interval, 0.93-1.31). Results were similar when analysis was restricted to the more specific outcome of kidney stone surgery. Neither a history of prior kidney stones nor the type of thiazide diuretic modified the effect of diuretic dose on outcome. Limitations Patients were >65 years old and we were unable to adjust for some potential confounders such as dietary factors. Conclusions Lower dose thiazide diuretics appear to confer a similar protective effect as higher dose thiazides against the development of kidney stones.
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Affiliation(s)
- R Todd Alexander
- Departments of Pediatrics & Physiology, University of Alberta, Edmonton, Canada
| | - Eric McArthur
- Institute for Clinical Evaluative Sciences, ON, Canada
| | | | - Blayne Welk
- Institute for Clinical Evaluative Sciences, ON, Canada.,Department of Surgery, Western University, London, ON, Canada.,Department of Epidemiology and Biostatistics, Western University, London, ON, Canada
| | - Daniel G Fuster
- Division of Nephrology and Hypertension, Bern University Hospital, Switzerland
| | - Amit X Garg
- Institute for Clinical Evaluative Sciences, ON, Canada.,Department of Epidemiology and Biostatistics, Western University, London, ON, Canada.,Department of Medicine, Western University, London, ON, Canada
| | - Robert R Quinn
- Departments of Medicine and Community Health Sciences, University of Calgary, AB, Canada
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Abstract
Renal tubular acidosis (RTA) is comprised of a diverse group of congenital or acquired diseases with the common denominator of defective renal acid excretion with protean manifestation, but in adults, recurrent kidney stones and nephrocalcinosis are mainly found in presentation. Calcium phosphate (CaP) stones and nephrocalcinosis are frequently encountered in distal hypokalemic RTA type I. Alkaline urinary pH, hypocitraturia, and, less frequently, hypercalciuria are the tripartite lithogenic factors in distal RTA (dRTA) predisposing to CaP stone formation; the latter 2 are also commonly encountered in other causes of urolithiasis. Although the full blown syndrome is easily diagnosed by conventional clinical criteria, an attenuated forme fruste called incomplete dRTA typically evades clinical testing and is only uncovered by provocative acid-loading challenges. Stone formers (SFs) that cannot acidify urine of pH < 5.3 during acid loading are considered to have incomplete dRTA. However, urinary acidification capacity is not a dichotomous but rather a continuous trait, so incomplete dRTA is not a distinct entity but may be one end of a spectrum. Recent findings suggest that incomplete dRTA can be attributed to heterozygous carriers of hypofunctional V-ATPase. The value of incomplete dRTA diagnosis by provocative testing and genotyping candidate genes is a valuable research tool, but it remains unclear at the moment whether they alter clinical practice and needs further clarification. No randomized controlled trials have been performed in SFs with dRTA or CaP stones, and until such data are available, treatment of CaP stones are centered on reversing the biochemical abnormalities encountered in the metabolic workup. SFs with type I dRTA should receive alkali therapy, preferentially in the form of K-citrate delivered judiciously to treat the chronic acid retention that drives both stone formation and bone disease.
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Dhayat NA, Lüthi D, Schneider L, Mattmann C, Vogt B, Fuster DG. Distinct phenotype of kidney stone formers with renal phosphate leak. Nephrol Dial Transplant 2018; 34:129-137. [DOI: 10.1093/ndt/gfy170] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/05/2018] [Indexed: 01/09/2023] Open
Affiliation(s)
- Nasser A Dhayat
- Department of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland
| | - David Lüthi
- Department of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Lisa Schneider
- Department of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Cedric Mattmann
- Department of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Department of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland
- Swiss National Centre of Competence in Research (NCCR) TransCure, Bern, Switzerland
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
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Pathare G, Dhayat NA, Mohebbi N, Wagner CA, Bobulescu IA, Moe OW, Fuster DG. Changes in V-ATPase subunits of human urinary exosomes reflect the renal response to acute acid/alkali loading and the defects in distal renal tubular acidosis. Kidney Int 2018; 93:871-880. [PMID: 29310826 DOI: 10.1016/j.kint.2017.10.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/02/2017] [Accepted: 10/05/2017] [Indexed: 12/26/2022]
Abstract
In the kidney, final urinary acidification is achieved by V-ATPases expressed in type A intercalated cells. The B1 subunit of the V-ATPase is required for maximal urinary acidification, while the role of the homologous B2 subunit is less clear. Here we examined the effect of acute acid/alkali loading in humans on B1 and B2 subunit abundance in urinary exosomes in normal individuals and of acid loading in patients with distal renal tubular acidosis (dRTA). Specificities of B1 and B2 subunit antibodies were verified by yeast heterologously expressing human B1 and B2 subunits, and murine wild-type and B1-deleted kidney lysates. Acute ammonium chloride loading elicited systemic acidemia, a drop in urinary pH, and increased urinary ammonium excretion. Nadir urinary pH was achieved at four to five hours, and exosomal B1 abundance was significantly increased at two through six hours after ammonium chloride loading. After acute equimolar sodium bicarbonate loading, blood and urinary pH rose rapidly, with a concomitant reduction of exosomal B1 abundance within two hours, which remained lower throughout the test. In contrast, no change in exosomal B2 abundance was found following acid or alkali loading. In patients with inherited or acquired distal RTA, the urinary B1 subunit was extremely low or undetectable and did not respond to acid loading in urine, whereas no change in B2 subunit was found. Thus, both B1 and B2 subunits of the V-ATPase are detectable in human urinary exosomes, and acid and alkali loading or distal RTA cause changes in the B1 but not B2 subunit abundance in urinary exosomes.
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Affiliation(s)
- Ganesh Pathare
- Division of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland; National Centre of Competence in Research Transcure, University of Bern, Bern, Switzerland
| | - Nasser A Dhayat
- Division of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Nilufar Mohebbi
- Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
| | - Carsten A Wagner
- Institute of Physiology, University of Zurich, Zurich, Switzerland; National Center for Competence in Research Kidney.CH, Zurich, Switzerland
| | - Ion A Bobulescu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA; Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Orson W Moe
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA; Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA; Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Daniel G Fuster
- Division of Nephrology and Hypertension, Bern University Hospital, University of Bern, Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland; National Centre of Competence in Research Transcure, University of Bern, Bern, Switzerland.
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35
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Dhayat NA, Gradwell MW, Pathare G, Anderegg M, Schneider L, Luethi D, Mattmann C, Moe OW, Vogt B, Fuster DG. Furosemide/Fludrocortisone Test and Clinical Parameters to Diagnose Incomplete Distal Renal Tubular Acidosis in Kidney Stone Formers. Clin J Am Soc Nephrol 2017; 12:1507-1517. [PMID: 28775126 PMCID: PMC5586565 DOI: 10.2215/cjn.01320217] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Accepted: 05/12/2017] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Incomplete distal renal tubular acidosis is a well known cause of calcareous nephrolithiasis but the prevalence is unknown, mostly due to lack of accepted diagnostic tests and criteria. The ammonium chloride test is considered as gold standard for the diagnosis of incomplete distal renal tubular acidosis, but the furosemide/fludrocortisone test was recently proposed as an alternative. Because of the lack of rigorous comparative studies, the validity of the furosemide/fludrocortisone test in stone formers remains unknown. In addition, the performance of conventional, nonprovocative parameters in predicting incomplete distal renal tubular acidosis has not been studied. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We conducted a prospective study in an unselected cohort of 170 stone formers that underwent sequential ammonium chloride and furosemide/fludrocortisone testing. RESULTS Using the ammonium chloride test as gold standard, the prevalence of incomplete distal renal tubular acidosis was 8%. Sensitivity and specificity of the furosemide/fludrocortisone test were 77% and 85%, respectively, yielding a positive predictive value of 30% and a negative predictive value of 98%. Testing of several nonprovocative clinical parameters in the prediction of incomplete distal renal tubular acidosis revealed fasting morning urinary pH and plasma potassium as the most discriminative parameters. The combination of a fasting morning urinary threshold pH <5.3 with a plasma potassium threshold >3.8 mEq/L yielded a negative predictive value of 98% with a sensitivity of 85% and a specificity of 77% for the diagnosis of incomplete distal renal tubular acidosis. CONCLUSIONS The furosemide/fludrocortisone test can be used for incomplete distal renal tubular acidosis screening in stone formers, but an abnormal furosemide/fludrocortisone test result needs confirmation by ammonium chloride testing. Our data furthermore indicate that incomplete distal renal tubular acidosis can reliably be excluded in stone formers by use of nonprovocative clinical parameters.
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Affiliation(s)
- Nasser A. Dhayat
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
| | - Michael W. Gradwell
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
| | - Ganesh Pathare
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
- Swiss National Centre of Competence in Research TransCure, University of Bern, Bern, Switzerland
| | - Manuel Anderegg
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
- Swiss National Centre of Competence in Research TransCure, University of Bern, Bern, Switzerland
| | - Lisa Schneider
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
| | - David Luethi
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
| | - Cedric Mattmann
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
| | - Orson W. Moe
- Departments of Internal Medicine and Physiology, and the Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas; and
| | - Bruno Vogt
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
| | - Daniel G. Fuster
- Division of Nephrology and Hypertension, Bern University Hospital, Bern, Switzerland
- Swiss National Centre of Competence in Research TransCure, University of Bern, Bern, Switzerland
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36
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Wnuk M, Anderegg MA, Graber WA, Buergy R, Fuster DG, Djonov V. Neuropilin1 regulates glomerular function and basement membrane composition through pericytes in the mouse kidney. Kidney Int 2016; 91:868-879. [PMID: 27988210 DOI: 10.1016/j.kint.2016.10.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/04/2016] [Accepted: 10/06/2016] [Indexed: 12/28/2022]
Abstract
Neuropilin1 (Nrp1) is a co-receptor best known to regulate the development of endothelial cells and is a target of anticancer therapies. However, its role in other vascular cells including pericytes is emergent. The kidney is an organ with high pericyte density and cancer patients develop severe proteinuria following administration of NRP1B-neutralizing antibody combined with bevacizumab. Therefore, we investigated whether Nrp1 regulates glomerular capillary integrity after completion of renal development using two mouse models; tamoxifen-inducible NG2Cre to delete Nrp1 specifically in pericytes and administration of Nrp1-neutralizing antibodies. Specific Nrp1 deletion in pericytes did not affect pericyte number but mutant mice developed hematuria with glomerular basement membrane defects. Despite foot process effacement, albuminuria was absent and expression of podocyte proteins remained unchanged upon Nrp1 deletion. Additionally, these mice displayed dilation of the afferent arteriole and glomerular capillaries leading to glomerular hyperfiltration. Nidogen-1 mRNA was downregulated and collagen4α3 mRNA was upregulated with no significant effect on the expression of other basement membrane genes in the mutant mice. These features were phenocopied by treating wild-type mice with Nrp1-neutralizing antibodies. Thus, our results reveal a postdevelopmental role of Nrp1 in renal pericytes as an important regulator of glomerular basement membrane integrity. Furthermore, our study offers novel mechanistic insights into renal side effects of Nrp1 targeting cancer therapies.
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Affiliation(s)
- Monika Wnuk
- Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Manuel A Anderegg
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | | | - Regula Buergy
- Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland; Division of Nephrology, Hypertension, and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Valentin Djonov
- Institute of Anatomy, University of Bern, Bern, Switzerland.
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Albano G, Dolder S, Siegrist M, Mercier-Zuber A, Auberson M, Stoudmann C, Hofstetter W, Bonny O, Fuster DG. Increased bone resorption by osteoclast-specific deletion of the sodium/calcium exchanger isoform 1 (NCX1). Pflugers Arch 2016; 469:225-233. [PMID: 27942992 DOI: 10.1007/s00424-016-1923-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/22/2016] [Accepted: 11/29/2016] [Indexed: 11/30/2022]
Abstract
Calcium is a key component of the bone mineral hydroxyapatite. During osteoclast-mediated bone resorption, hydroxyapatite is dissolved and significant quantities of calcium are released. Several calcium transport systems have previously been identified in osteoclasts, including members of the sodium/calcium exchanger (NCX) family. Expression pattern and physiological role of NCX isoforms in osteoclasts, however, remain largely unknown at the moment. Our data indicate that all three NCX isoforms (NCX1, NCX2, and NCX3) are present in murine osteoclasts. RANKL-induced differentiation of murine osteoclast precursors into mature osteoclasts significantly attenuated the expression of NCX1, while NCX2 and NCX3 expressions were largely unaffected. To study the role of NCX1 during osteoclast differentiation and bone resorption, we crossed mice with exon 11 of the NCX1 gene flanked by loxP sites with cathepsin K-Cre transgenic mice. Mature osteoclasts derived from transgenic mice exhibited an 80-90% reduction of NCX1 protein. In vitro studies indicate that NCX1 is dispensable for osteoclast differentiation, but NCX1-deficient osteoclasts exhibited increased resorptive activity. In line with these in vitro findings, mice with an osteoclast-targeted deletion of the NCX1 gene locus displayed an age-dependent loss of bone mass. Thus, in summary, our data reveal NCX1 as a regulator of osteoclast-mediated bone resorption.
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Affiliation(s)
- Giuseppe Albano
- Division of Nephrology, Hypertension and Clinical Pharmacology, Bern University Hospital, University of Bern, Freiburgstrasse 15, 3010, Bern, Switzerland
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
- NCCR Transcure, University of Bern, Bern, Switzerland
- Department of Clinical Research, University of Bern, Bern, Switzerland
- NCCR Kidney.CH, University of Zürich, Zürich, Switzerland
| | - Silvia Dolder
- NCCR Transcure, University of Bern, Bern, Switzerland
- Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Mark Siegrist
- NCCR Transcure, University of Bern, Bern, Switzerland
- Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Annie Mercier-Zuber
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
- NCCR Kidney.CH, University of Zürich, Zürich, Switzerland
| | - Muriel Auberson
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
- NCCR Kidney.CH, University of Zürich, Zürich, Switzerland
| | - Candice Stoudmann
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
- NCCR Kidney.CH, University of Zürich, Zürich, Switzerland
| | - Willy Hofstetter
- NCCR Transcure, University of Bern, Bern, Switzerland
- Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Olivier Bonny
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
- NCCR Kidney.CH, University of Zürich, Zürich, Switzerland
| | - Daniel G Fuster
- Division of Nephrology, Hypertension and Clinical Pharmacology, Bern University Hospital, University of Bern, Freiburgstrasse 15, 3010, Bern, Switzerland.
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland.
- NCCR Transcure, University of Bern, Bern, Switzerland.
- Department of Clinical Research, University of Bern, Bern, Switzerland.
- NCCR Kidney.CH, University of Zürich, Zürich, Switzerland.
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Deisl C, Anderegg M, Albano G, Lüscher BP, Cerny D, Soria R, Bouillet E, Rimoldi S, Scherrer U, Fuster DG. Loss of Sodium/Hydrogen Exchanger NHA2 Exacerbates Obesity- and Aging-Induced Glucose Intolerance in Mice. PLoS One 2016; 11:e0163568. [PMID: 27685945 PMCID: PMC5042380 DOI: 10.1371/journal.pone.0163568] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/11/2016] [Indexed: 11/21/2022] Open
Abstract
We previously demonstrated that the sodium/hydrogen exchanger NHA2, also known as NHEDC2 or SLC9B2, is critical for insulin secretion by β–cells. To gain more insights into the role of NHA2 on systemic glucose homeostasis, we studied the impact of loss of NHA2 during the physiological aging process and in the setting of diet-induced obesity. While glucose tolerance was normal at 2 months of age, NHA2 KO mice displayed a significant glucose intolerance at 5 and 12 months of age, respectively. An obesogenic high fat diet further exacerbated the glucose intolerance of NHA2 KO mice. Insulin levels remained similar in NHA2 KO and WT mice during aging and high fat diet, but fasting insulin/glucose ratios were significantly lower in NHA2 KO mice. Peripheral insulin sensitivity, measured by insulin tolerance tests and hyperinsulinemic euglycemic clamps, was unaffected by loss of NHA2 during aging and high fat diet. High fat diet diminished insulin secretion capacity in both WT and NHA2 KO islets and reduced expression of NHA2 in WT islets. In contrast, aging was characterized by a gradual increase of NHA2 expression in islets, paralleled by an increasing difference in insulin secretion between WT and NHA2 KO islets. In summary, our results demonstrate that loss of the sodium/hydrogen exchanger NHA2 exacerbates obesity- and aging-induced glucose intolerance in mice. Furthermore, our data reveal a close link between NHA2 expression and insulin secretion capacity in islets.
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Affiliation(s)
- Christine Deisl
- Division of Nephrology, Hypertension and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland
- Institute of Biochemistry and Molecular Medicine and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
| | - Manuel Anderegg
- Division of Nephrology, Hypertension and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland
- Institute of Biochemistry and Molecular Medicine and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
| | - Giuseppe Albano
- Division of Nephrology, Hypertension and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland
- Institute of Biochemistry and Molecular Medicine and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
| | - Benjamin P. Lüscher
- Institute of Biochemistry and Molecular Medicine and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
| | - David Cerny
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
- Division of Cardiology, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Rodrigo Soria
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
- Division of Cardiology, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Elisa Bouillet
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
- Division of Cardiology, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Stefano Rimoldi
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
- Division of Cardiology, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Urs Scherrer
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
- Division of Cardiology, Bern University Hospital, University of Bern, Bern, Switzerland
- Facultad de Ciencias, Departamento de Biologia, Universidad de Tarapaca, Arica, Chile
| | - Daniel G. Fuster
- Division of Nephrology, Hypertension and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland
- Institute of Biochemistry and Molecular Medicine and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
- Department of Clinical Research, Bern University Hospital, University of Bern, Bern Switzerland
- * E-mail:
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Dhayat NA, Ackermann D, Pruijm M, Ponte B, Ehret G, Guessous I, Leichtle AB, Paccaud F, Mohaupt M, Fiedler GM, Devuyst O, Pechère-Bertschi A, Burnier M, Martin PY, Bochud M, Vogt B, Fuster DG. Fibroblast growth factor 23 and markers of mineral metabolism in individuals with preserved renal function. Kidney Int 2016; 90:648-57. [PMID: 27370409 DOI: 10.1016/j.kint.2016.04.024] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 04/21/2016] [Accepted: 04/28/2016] [Indexed: 12/01/2022]
Abstract
Fibroblast growth factor 23 (FGF23) is a bone-derived hormone that regulates phosphate homeostasis. Circulating FGF23 is elevated in chronic kidney disease (CKD) and independently associated with poor renal and cardiovascular outcomes and mortality. Because the study of FGF23 in individuals with normal renal function has received little attention, we examined in a large, population-based study of 1128 participants the associations of FGF23 with markers of mineral metabolism and renal function. The median estimated glomerular filtration rate (eGFR) of the cohort was 105 ml/min per 1.73 m(2), and the median plasma FGF23 was 78.5 RU/ml. FGF23 increased and plasma 1,25-dihydroxyvitamin D3 decreased significantly below an eGFR threshold of 102 and 99 ml/min per 1.73 m(2), respectively. In contrast, plasma parathyroid hormone increased continuously with decreasing eGFR and was first significantly elevated at an eGFR of 126 ml/min per 1.73 m(2). On multivariable analysis adjusting for sex, age, body mass index, and GFR, FGF23 was negatively associated with 1,25-dihydroxyvitamin D3, and urinary absolute and fractional calcium excretion but not with serum calcium or parathyroid hormone. We found a positive association of FGF23 with plasma phosphate, but no association with urinary absolute or fractional phosphate excretion and, unexpectedly, a positive association with tubular maximum phosphate reabsorption/GFR. Thus, in the absence of CKD, parathyroid hormone increases earlier than FGF23 when the eGFR decreases. The increase in FGF23 occurs at a higher eGFR threshold than previously reported and is closely associated with a decrease in 1,25-dihydroxyvitamin D3. We speculate that the main demonstrable effect of FGF23 in the setting of preserved renal function is suppression of 1,25-dihydroxyvitamin D3 rather than stimulation of renal phosphate excretion.
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Affiliation(s)
- Nasser A Dhayat
- Department of Nephrology, Hypertension, and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Daniel Ackermann
- Department of Nephrology, Hypertension, and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Menno Pruijm
- Nephrology Service, University Hospital of Lausanne, Lausanne, Switzerland
| | - Belen Ponte
- Nephrology Service, Department of Specialties of Internal Medicine, University Hospital of Geneva, Geneva, Switzerland
| | - Georg Ehret
- Cardiology Service, Department of Specialties of Internal Medicine, University Hospital of Geneva, Geneva, Switzerland
| | - Idris Guessous
- Department of Community Medicine, Primary Care and Emergency Medicine, University Hospital of Geneva, Geneva, Switzerland; Institute of Social and Preventive Medicine, University Hospital of Lausanne, Lausanne, Switzerland
| | - Alexander Benedikt Leichtle
- Department of Laboratory Medicine, Bern University Hospital, University of Bern, Bern, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Fred Paccaud
- Institute of Social and Preventive Medicine, University Hospital of Lausanne, Lausanne, Switzerland
| | - Markus Mohaupt
- Department of Nephrology, Hypertension, and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Georg-Martin Fiedler
- Department of Laboratory Medicine, Bern University Hospital, University of Bern, Bern, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Olivier Devuyst
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Antoinette Pechère-Bertschi
- Endocrinology Service, Department of Internal Medicine Specialties, University Hospital of Geneva, Geneva, Switzerland
| | - Michel Burnier
- Nephrology Service, University Hospital of Lausanne, Lausanne, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Pierre-Yves Martin
- Nephrology Service, Department of Specialties of Internal Medicine, University Hospital of Geneva, Geneva, Switzerland
| | - Murielle Bochud
- Institute of Social and Preventive Medicine, University Hospital of Lausanne, Lausanne, Switzerland
| | - Bruno Vogt
- Department of Nephrology, Hypertension, and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Department of Nephrology, Hypertension, and Clinical Pharmacology, Bern University Hospital, University of Bern, Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland.
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40
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Dhayat N, Ackermann D, Pruijm M, Ponte B, Ehret G, Guessous I, Leichtle AB, Paccaud F, Mohaupt M, Fiedler GM, Devuyst O, Pechère-Bertschi A, Burnier M, Martin PY, Bochud M, Vogt B, Fuster DG. MP359FGF23 AND MARKERS OF MINERAL METABOLISM IN SUBJECTS WITH PRESERVED RENAL FUNCTION. Nephrol Dial Transplant 2016. [DOI: 10.1093/ndt/gfw190.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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41
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Dhayat NA, Schaller A, Albano G, Poindexter J, Griffith C, Pasch A, Gallati S, Vogt B, Moe OW, Fuster DG. The Vacuolar H+-ATPase B1 Subunit Polymorphism p.E161K Associates with Impaired Urinary Acidification in Recurrent Stone Formers. J Am Soc Nephrol 2015; 27:1544-54. [PMID: 26453614 DOI: 10.1681/asn.2015040367] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 09/02/2015] [Indexed: 11/03/2022] Open
Abstract
Mutations in the vacuolar-type H(+)-ATPase B1 subunit gene ATP6V1B1 cause autosomal-recessive distal renal tubular acidosis (dRTA). We previously identified a single-nucleotide polymorphism (SNP) in the human B1 subunit (c.481G>A; p.E161K) that causes greatly diminished pump function in vitro To investigate the effect of this SNP on urinary acidification, we conducted a genotype-phenotype analysis of recurrent stone formers in the Dallas and Bern kidney stone registries. Of 555 patients examined, 32 (5.8%) were heterozygous for the p.E161K SNP, and the remaining 523 (94.2%) carried two wild-type alleles. After adjustment for sex, age, body mass index, and dietary acid and alkali intake, p.E161K SNP carriers had a nonsignificant tendency to higher urinary pH on a random diet (6.31 versus 6.09; P=0.09). Under an instructed low-Ca and low-Na diet, urinary pH was higher in p.E161K SNP carriers (6.56 versus 6.01; P<0.01). Kidney stones of p.E161K carriers were more likely to contain calcium phosphate than stones of wild-type patients. In acute NH4Cl loading, p.E161K carriers displayed a higher trough urinary pH (5.34 versus 4.89; P=0.01) than wild-type patients. Overall, 14.6% of wild-type patients and 52.4% of p.E161K carriers were unable to acidify their urine below pH 5.3 and thus, can be considered to have incomplete dRTA. In summary, our data indicate that recurrent stone formers with the vacuolar H(+)-ATPase B1 subunit p.E161K SNP exhibit a urinary acidification deficit with an increased prevalence of calcium phosphate-containing kidney stones. The burden of E161K heterozygosity may be a forme fruste of dRTA.
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Affiliation(s)
- Nasser A Dhayat
- Swiss National Centres of Competence in Research Kidney.CH and TransCure and Divisions of Nephrology, Hypertension and Clinical Pharmacology, Clinical Research, Bern University Hospital, University of Bern, Switzerland; and
| | - Andre Schaller
- Clinical Research, Bern University Hospital, University of Bern, Switzerland; and Human Genetics, and Departments of Pediatrics and
| | - Giuseppe Albano
- Swiss National Centres of Competence in Research Kidney.CH and TransCure and Divisions of Nephrology, Hypertension and Clinical Pharmacology, Clinical Research, Bern University Hospital, University of Bern, Switzerland; and Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | - John Poindexter
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, and
| | - Carolyn Griffith
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, and
| | - Andreas Pasch
- Swiss National Centres of Competence in Research Kidney.CH and TransCure and Divisions of Nephrology, Hypertension and Clinical Pharmacology, Clinical Research, Bern University Hospital, University of Bern, Switzerland; and
| | - Sabina Gallati
- Clinical Research, Bern University Hospital, University of Bern, Switzerland; and Human Genetics, and Departments of Pediatrics and
| | - Bruno Vogt
- Swiss National Centres of Competence in Research Kidney.CH and TransCure and Divisions of Nephrology, Hypertension and Clinical Pharmacology, Clinical Research, Bern University Hospital, University of Bern, Switzerland; and
| | - Orson W Moe
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, and Departments of Internal Medicine and Physiology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Daniel G Fuster
- Swiss National Centres of Competence in Research Kidney.CH and TransCure and Divisions of Nephrology, Hypertension and Clinical Pharmacology, Clinical Research, Bern University Hospital, University of Bern, Switzerland; and Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland;
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42
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Dhayat N, Simonin A, Anderegg M, Pathare G, Lüscher BP, Deisl C, Albano G, Mordasini D, Hediger MA, Surbek DV, Vogt B, Sass JO, Kloeckener-Gruissem B, Fuster DG. Mutation in the Monocarboxylate Transporter 12 Gene Affects Guanidinoacetate Excretion but Does Not Cause Glucosuria. J Am Soc Nephrol 2015; 27:1426-36. [PMID: 26376857 DOI: 10.1681/asn.2015040411] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 08/05/2015] [Indexed: 01/08/2023] Open
Abstract
A heterozygous mutation (c.643C>A; p.Q215X) in the monocarboxylate transporter 12-encoding gene MCT12 (also known as SLC16A12) that mediates creatine transport was recently identified as the cause of a syndrome with juvenile cataracts, microcornea, and glucosuria in a single family. Whereas the MCT12 mutation cosegregated with the eye phenotype, poor correlation with the glucosuria phenotype did not support a pathogenic role of the mutation in the kidney. Here, we examined MCT12 in the kidney and found that it resides on basolateral membranes of proximal tubules. Patients with MCT12 mutation exhibited reduced plasma levels and increased fractional excretion of guanidinoacetate, but normal creatine levels, suggesting that MCT12 may function as a guanidinoacetate transporter in vivo However, functional studies in Xenopus oocytes revealed that MCT12 transports creatine but not its precursor, guanidinoacetate. Genetic analysis revealed a separate, undescribed heterozygous mutation (c.265G>A; p.A89T) in the sodium/glucose cotransporter 2-encoding gene SGLT2 (also known as SLC5A2) in the family that segregated with the renal glucosuria phenotype. When overexpressed in HEK293 cells, the mutant SGLT2 transporter did not efficiently translocate to the plasma membrane, and displayed greatly reduced transport activity. In summary, our data indicate that MCT12 functions as a basolateral exit pathway for creatine in the proximal tubule. Heterozygous mutation of MCT12 affects systemic levels and renal handling of guanidinoacetate, possibly through an indirect mechanism. Furthermore, our data reveal a digenic syndrome in the index family, with simultaneous MCT12 and SGLT2 mutation. Thus, glucosuria is not part of the MCT12 mutation syndrome.
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Affiliation(s)
- Nasser Dhayat
- Division of Nephrology, Hypertension and Clinical Pharmacology, and Department of Clinical Research, University of Bern, Switzerland
| | - Alexandre Simonin
- Institute of Biochemistry and Molecular Medicine, Swiss National Centre of Competence in Research Transcure, and
| | - Manuel Anderegg
- Division of Nephrology, Hypertension and Clinical Pharmacology, and Department of Clinical Research, University of Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, Swiss National Centre of Competence in Research Transcure, and
| | - Ganesh Pathare
- Division of Nephrology, Hypertension and Clinical Pharmacology, and Department of Clinical Research, University of Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, Swiss National Centre of Competence in Research Transcure, and
| | - Benjamin P Lüscher
- Department of Clinical Research, University of Bern, Switzerland; Swiss National Centre of Competence in Research Transcure, and Department of Obstetrics and Gynecology, University Hospital of Bern, Switzerland
| | - Christine Deisl
- Division of Nephrology, Hypertension and Clinical Pharmacology, and Department of Clinical Research, University of Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, Swiss National Centre of Competence in Research Transcure, and
| | - Giuseppe Albano
- Division of Nephrology, Hypertension and Clinical Pharmacology, and Department of Clinical Research, University of Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, Swiss National Centre of Competence in Research Transcure, and
| | - David Mordasini
- Division of Nephrology, Hypertension and Clinical Pharmacology, and Department of Clinical Research, University of Bern, Switzerland
| | - Matthias A Hediger
- Institute of Biochemistry and Molecular Medicine, Swiss National Centre of Competence in Research Transcure, and Department of Obstetrics and Gynecology, University Hospital of Bern, Switzerland
| | - Daniel V Surbek
- Department of Clinical Research, University of Bern, Switzerland; Swiss National Centre of Competence in Research Transcure, and Department of Obstetrics and Gynecology, University Hospital of Bern, Switzerland
| | - Bruno Vogt
- Division of Nephrology, Hypertension and Clinical Pharmacology, and Department of Clinical Research, University of Bern, Switzerland
| | - Jörn Oliver Sass
- Division of Clinical Chemistry and Biochemistry, Children's Research Center, University Children's Hospital, Zürich, Switzerland; Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach, Germany
| | - Barbara Kloeckener-Gruissem
- Institute of Medical Molecular Genetics, University of Zürich, Zürich, Switzerland; and Department of Biology, Swiss Federal Institute of Technology in Zürich, Zürich, Switzerland
| | - Daniel G Fuster
- Division of Nephrology, Hypertension and Clinical Pharmacology, and Department of Clinical Research, University of Bern, Switzerland; Institute of Biochemistry and Molecular Medicine, Swiss National Centre of Competence in Research Transcure, and
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Affiliation(s)
- Andreas Haeberlin
- Department of Cardiology, Bern University Hospital and University of Bern, Bern, Switzerland.,ARTORG Center for Biomedical Engineering, University of Bern, Bern, Switzerland.,Department of Nephrology, Hypertension and Clinical Pharmacology, Bern University Hospital and University of Bern, Bern, Switzerland
| | - Daniel G Fuster
- Department of Nephrology, Hypertension and Clinical Pharmacology, Bern University Hospital and University of Bern, Bern, Switzerland
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44
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Zhang J, Fuster DG, Cameron MA, Quiñones H, Griffith C, Xie XS, Moe OW. Incomplete distal renal tubular acidosis from a heterozygous mutation of the V-ATPase B1 subunit. Am J Physiol Renal Physiol 2014; 307:F1063-71. [PMID: 25164082 DOI: 10.1152/ajprenal.00408.2014] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Congenital distal renal tubular acidosis (RTA) from mutations of the B1 subunit of V-ATPase is considered an autosomal recessive disease. We analyzed a distal RTA kindred with a truncation mutation of B1 (p.Phe468fsX487) previously shown to have failure of assembly into the V1 domain of V-ATPase. All heterozygous carriers in this kindred have normal plasma HCO3- concentrations and thus evaded the diagnosis of RTA. However, inappropriately high urine pH, hypocitraturia, and hypercalciuria were present either individually or in combination in the heterozygotes at baseline. Two of the heterozygotes studied also had inappropriate urinary acidification with acute ammonium chloride loading and an impaired urine-blood Pco2 gradient during bicarbonaturia, indicating the presence of a H+ gradient and flux defects. In normal human renal papillae, wild-type B1 is located primarily on the plasma membrane, but papilla from one of the heterozygote who had kidney stones but not nephrocalcinosis showed B1 in both the plasma membrane as well as diffuse intracellular staining. Titration of increasing amounts of the mutant B1 subunit did not exhibit negative dominance over the expression, cellular distribution, or H+ pump activity of wild-type B1 in mammalian human embryonic kidney-293 cells and in V-ATPase-deficient Saccharomyces cerevisiae. This is the first demonstration of renal acidification defects and nephrolithiasis in heterozygous carriers of a mutant B1 subunit that cannot be attributable to negative dominance. We propose that heterozygosity may lead to mild real acidification defects due to haploinsufficiency. B1 heterozygosity should be considered in patients with calcium nephrolithiasis and urinary abnormalities such as alkalinuria or hypocitraturia.
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Affiliation(s)
- Jianning Zhang
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Daniel G Fuster
- Department of Nephrology and Hypertension and Institute of Biochemistry and Molecular Medicine, Inselspital, University of Bern, Bern, Switzerland
| | - Mary Ann Cameron
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Henry Quiñones
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Carolyn Griffith
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Xiao-Song Xie
- McDermott Center of Human Development, University of Texas Southwestern Medical Center, Dallas, Texas; and
| | - Orson W Moe
- Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas; Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas;
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45
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Fuster DG, Alexander RT. Traditional and emerging roles for the SLC9 Na+/H+ exchangers. Pflugers Arch 2013; 466:61-76. [PMID: 24337822 DOI: 10.1007/s00424-013-1408-8] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 11/14/2013] [Accepted: 11/20/2013] [Indexed: 10/25/2022]
Abstract
The SLC9 gene family encodes Na(+)/H(+) exchangers (NHEs). These transmembrane proteins transport ions across lipid bilayers in a diverse array of species from prokaryotes to eukaryotes, including plants, fungi, and animals. They utilize the electrochemical gradient of one ion to transport another ion against its electrochemical gradient. Currently, 13 evolutionarily conserved NHE isoforms are known in mammals [22, 46, 128]. The SLC9 gene family (solute carrier classification of transporters: www.bioparadigms.org) is divided into three subgroups [46]. The SLC9A subgroup encompasses plasmalemmal isoforms NHE1-5 (SLC9A1-5) and the predominantly intracellular isoforms NHE6-9 (SLC9A6-9). The SLC9B subgroup consists of two recently cloned isoforms, NHA1 and NHA2 (SLC9B1 and SLC9B2, respectively). The SLC9C subgroup consist of a sperm specific plasmalemmal NHE (SLC9C1) and a putative NHE, SLC9C2, for which there is currently no functional data [46]. NHEs participate in the regulation of cytosolic and organellar pH as well as cell volume. In the intestine and kidney, NHEs are critical for transepithelial movement of Na(+) and HCO3(-) and thus for whole body volume and acid-base homeostasis [46]. Mutations in the NHE6 or NHE9 genes cause neurological disease in humans and are currently the only NHEs directly linked to human disease. However, it is becoming increasingly apparent that members of this gene family contribute to the pathophysiology of multiple human diseases.
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Affiliation(s)
- Daniel G Fuster
- Division of Nephrology, Hypertension and Clinical Pharmacology and Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland,
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46
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Rexhaj E, Paoloni-Giacobino A, Rimoldi SF, Fuster DG, Anderegg M, Somm E, Bouillet E, Allemann Y, Sartori C, Scherrer U. Mice generated by in vitro fertilization exhibit vascular dysfunction and shortened life span. J Clin Invest 2013; 123:5052-60. [PMID: 24270419 PMCID: PMC3859389 DOI: 10.1172/jci68943] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 09/04/2013] [Indexed: 12/11/2022] Open
Abstract
Children conceived by assisted reproductive technologies (ART) display a level of vascular dysfunction similar to that seen in children of mothers with preeclamspia. The long-term consequences of ART-associated vascular disorders are unknown and difficult to investigate in healthy children. Here, we found that vasculature from mice generated by ART display endothelial dysfunction and increased stiffness, which translated into arterial hypertension in vivo. Progeny of male ART mice also exhibited vascular dysfunction, suggesting underlying epigenetic modifications. ART mice had altered methylation at the promoter of the gene encoding eNOS in the aorta, which correlated with decreased vascular eNOS expression and NO synthesis. Administration of a deacetylase inhibitor to ART mice normalized vascular gene methylation and function and resulted in progeny without vascular dysfunction. The induction of ART-associated vascular and epigenetic alterations appeared to be related to the embryo environment; these alterations were possibly facilitated by the hormonally stimulated ovulation accompanying ART. Finally, ART mice challenged with a high-fat diet had roughly a 25% shorter life span compared with control animals. This study highlights the potential of ART to induce vascular dysfunction and shorten life span and suggests that epigenetic alterations contribute to these problems.
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Affiliation(s)
- Emrush Rexhaj
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Ariane Paoloni-Giacobino
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Stefano F. Rimoldi
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Daniel G. Fuster
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Manuel Anderegg
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Emmanuel Somm
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Elisa Bouillet
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Yves Allemann
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Claudio Sartori
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
| | - Urs Scherrer
- Swiss Cardiovascular Center Bern and Department of Clinical Research, University Hospital, Bern, Switzerland.
Department of Genetic and Laboratory Medicine and Swiss Center for Applied Human Toxicology, Geneva University Hospital, Geneva, Switzerland.
Division of Nephrology, Hypertension and Clinical Pharmacology, University Hospital, Bern, Switzerland.
Division of Development and Growth, Department of Paediatrics, University of Geneva Medical School, Geneva, Switzerland.
Department of Internal Medicine, CHUV, Lausanne, Switzerland.
Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile
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Arampatzis S, Fuster DG. Gangrene and osteolysis in pancreatic insufficiency. Kidney Int 2012; 82:364. [PMID: 22791328 DOI: 10.1038/ki.2012.72] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Spyridon Arampatzis
- Department of Nephrology and Hypertension, University Hospital of Bern, Bern, Switzerland.
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Hofstetter W, Siegrist M, Simonin A, Bonny O, Fuster DG. Sodium/hydrogen exchanger NHA2 in osteoclasts: subcellular localization and role in vitro and in vivo. Bone 2010; 47:331-40. [PMID: 20441802 DOI: 10.1016/j.bone.2010.04.605] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 04/26/2010] [Accepted: 04/26/2010] [Indexed: 11/29/2022]
Abstract
NHA2 was recently identified as a novel sodium/hydrogen exchanger which is strongly upregulated during RANKL-induced osteoclast differentiation. Previous in vitro studies suggested that NHA2 is a mitochondrial transporter required for osteoclast differentiation and bone resorption. Due to the lack of suitable antibodies, NHA2 was studied only on RNA level thus far. To define the protein's role in osteoclasts in vitro and in vivo, we generated NHA2-deficient mice and raised several specific NHA2 antibodies. By confocal microscopy and subcellular fractionation studies, NHA2 was found to co-localize with the late endosomal and lysosomal marker LAMP1 and the V-ATPase a3 subunit, but not with mitochondrial markers. Immunofluorescence studies and surface biotinylation experiments further revealed that NHA2 was highly enriched in the plasma membrane of osteoclasts, localizing to the basolateral membrane of polarized osteoclasts. Despite strong upregulation of NHA2 during RANKL-induced osteoclast differentiation, however, structural parameters of bone, quantified by high-resolution microcomputed tomography, were not different in NHA2-deficient mice compared to wild-type littermates. In addition, in vitro RANKL stimulation of bone marrow cells isolated from wild-type and NHA2-deficient mice yielded no differences in osteoclast development and activity. Taken together, we show that NHA2 is a RANKL-induced plasmalemmal sodium/hydrogen exchanger in osteoclasts. However, our data from NHA2-deficient mice suggest that NHA2 is dispensable for osteoclast differentiation and bone resorption both in vitro and in vivo.
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Affiliation(s)
- Willy Hofstetter
- Group for Bone Biology and Orthopaedic Research, Department of Clinical Research, University of Bern, Bern, Switzerland
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Babich V, Bobulescu IA, Fuster DG, Gisler S, Bonny O, Hilgemann D, Stagljar I, Moe OW. Dimerization of the plasma membrane Na
+
/H
+
exchanger type 3 (NHE3). FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.815.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Victor Babich
- University of Texas Southwestern Medical CenterDallasTX
| | | | | | - Serge Gisler
- University of Texas Southwestern Medical CenterDallasTX
| | - Olivier Bonny
- University of Texas Southwestern Medical CenterDallasTX
| | | | | | - Orson W. Moe
- University of Texas Southwestern Medical CenterDallasTX
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50
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Bobulescu IA, Quiñones H, Gisler SM, Di Sole F, Hu MC, Shi M, Zhang J, Fuster DG, Wright N, Mumby M, Moe OW. Acute regulation of renal Na+/H+ exchanger NHE3 by dopamine: role of protein phosphatase 2A. Am J Physiol Renal Physiol 2010; 298:F1205-13. [PMID: 20181665 DOI: 10.1152/ajprenal.00708.2009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Nephrogenic dopamine is a potent natriuretic paracrine/autocrine hormone that is central for mammalian sodium homeostasis. In the renal proximal tubule, dopamine induces natriuresis partly via inhibition of the sodium/proton exchanger NHE3. The signal transduction pathways and mechanisms by which dopamine inhibits NHE3 are complex and incompletely understood. This manuscript describes the role of the serine/threonine protein phosphatase 2A (PP2A) in the regulation of NHE3 by dopamine. The PP2A regulatory subunit B56δ (coded by the Ppp2r5d gene) directly associates with more than one region of the carboxy-terminal hydrophilic putative cytoplasmic domain of NHE3 (NHE3-cyto), as demonstrated by yeast-two-hybrid, coimmunoprecipitation, blot overlay, and in vitro pull-down assays. Phosphorylated NHE3-cyto is a substrate for purified PP2A in an in vitro dephosphorylation reaction. In cultured renal cells, inhibition of PP2A by either okadaic acid or by overexpression of the simian virus 40 (SV40) small T antigen blocks the ability of dopamine to inhibit NHE3 activity and to reduce surface NHE3 protein. Dopamine-induced NHE3 redistribution is also blocked by okadaic acid ex vivo in rat kidney cortical slices. These studies demonstrate that PP2A is an integral and critical participant in the signal transduction pathway between dopamine receptor activation and NHE3 inhibition.
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Affiliation(s)
- I Alexandru Bobulescu
- Dept. of Internal Medicine, Div. of Nephrology, Univ. of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-8856, USA
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