1
|
Nawrocka-Millward S, Biegus J, Fudim M, Guzik M, Iwanek G, Ponikowski P, Zymliński R. The role of urine chloride in acute heart failure. Sci Rep 2024; 14:14100. [PMID: 38890417 PMCID: PMC11189561 DOI: 10.1038/s41598-024-64747-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 06/12/2024] [Indexed: 06/20/2024] Open
Abstract
In our retrospective study, we aimed to investigate the relationship between urinary chloride (uCl-) and selected clinical and laboratory biomarkers, renal function, and patient outcomes in the acute heart failure (AHF) population. We divided 248 adult patients (≥ 18 years) with AHF into two groups: low uCl- (< 115 mmol/L) and high uCl-. The mean age of the patient group was 70.2 ± 12.6, and 182 patients were male (73.4%). Clinical endpoints included in-hospital mortality, one-year mortality, and a composite endpoint of one-year mortality and rehospitalization for heart failure. Patients were followed up for at least one year. Relevant clinical and baseline biomarker data were collected, including markers concerning inflammation, liver and kidney function, perfusion and congestion, iron status, cardiac remodeling, gasometry, renin and aldosterone. Low uCl- was associated with worse in-hospital outcomes, including higher in-hospital mortality (7.7% vs. 1.4%, p = 0.014), the need for inotropic support (20.19% vs. 2.08%, p ≤ 0.001), worsening of HF during therapy (17.31% vs. 4.86%, p ≤ 0.001), and the need for treatment in an intensive cardiac care unit (33.65% vs. 15.28%, p ≤ 0.001). Low uCl- was a significant predictor of one-year mortality (40.4% vs. 16.7%, p < 0.05) and the composite outcome (HR 2.42, 95% CI 1.43-4.08, p < 0.001). In the multivariable analysis, uCl- was independently associated with the risk of one-year mortality (HR 0.92, 95% CI 0.87-0.98, p < 0.05) and the composite outcome (HR 0.95, 95% CI 0.92-0.99, p < 0.05). Our findings suggest that low uCl- is a marker of more advanced heart failure, activation of the renin-angiotensin-aldosterone system and is related to worse one-year outcomes.
Collapse
Affiliation(s)
| | - Jan Biegus
- University Clinical Hospital, Wroclaw, Poland
- Institute of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
| | - Marat Fudim
- Institute of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
- Division of Cardiology, Duke University Medical Center, Durham, NC, USA
- Duke Clinical Research Institute, Durham, NC, USA
| | - Mateusz Guzik
- University Clinical Hospital, Wroclaw, Poland
- Institute of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
| | - Gracjan Iwanek
- University Clinical Hospital, Wroclaw, Poland
- Institute of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
| | - Piotr Ponikowski
- University Clinical Hospital, Wroclaw, Poland
- Institute of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
| | - Robert Zymliński
- University Clinical Hospital, Wroclaw, Poland
- Institute of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
| |
Collapse
|
2
|
Wang F, Zhang Y, Gao M, Zeng X. TMEM16A inhibits renal tubulointerstitial fibrosis via Wnt/β-catenin signaling during hypertension nephropathy. Cell Signal 2024; 117:111088. [PMID: 38316267 DOI: 10.1016/j.cellsig.2024.111088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 02/07/2024]
Abstract
BACKGROUND AND OBJECTIVE Hypertensive nephropathy is the second leading cause of end-stage renal disease, but its underlying pathogenesis remains unclear. Therefore, this study aimed to explore whether transmembrane protein 16 A (TMEM16A), the molecular basis of calcium-activated chloride channels (CaCC), is involved in the development and progression of hypertensive nephropathy. METHODS In vivo and in vitro experiments were conducted using a hypertensive murine model and human kidney proximal tubular epithelial cells (HK-2 cells), respectively. EXPERIMENTAL RESULTS The expression of TMEM16A was down-regulated in renal samples of hypertensive nephropathy patients and hypertensive model mice, accompanied by excessive deposition of extracellular matrix proteins (ECM) such as Fibronectin, Laminin, Collagen I and Collagen III, the up-regulation of α-smooth muscle actin (α-SMA) expression, and the decrease of E-cadherin. Overexpression of TMEM16A or knockdown of TMEM16A inhibited or promoted the expression of Wnt/β-catenin signaling pathway proteins Wnt3a, LRP5 and active β-catenin in HK-2 cells, preventing the epithelial-to-mesenchymal transition (EMT) of renal tubules, and the synthesis of ECM components. CONCLUSION In angiotensin II (Ang II)-induced hypertensive nephropathy, TMEM16A was identified as a key player inhibiting the detrimental changes in renal tubules, suggesting a potential avenue for mitigating renal damage in hypertensive nephropathy.
Collapse
Affiliation(s)
- Feng Wang
- Department of Pharmacy, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518107, China; Yancheng TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Yancheng 224000, China
| | - Yiqing Zhang
- Department of Nephrology, Center of Kidney and Urology, the Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen 518107, China
| | - Min Gao
- Department of Pharmacy, The Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China.
| | - Xuelin Zeng
- Department of Pharmacy, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518107, China; Shenzhen Key Laboratory of Chinese Medicine Active Substance Creening and Translational Research, Sun Yat-sen University, Shenzhen 518107, China.
| |
Collapse
|
3
|
Ryu JY, Baek SH, Kim S. Evidence-based hyponatremia management in liver disease. Clin Mol Hepatol 2023; 29:924-944. [PMID: 37280091 PMCID: PMC10577348 DOI: 10.3350/cmh.2023.0090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 06/05/2023] [Accepted: 06/05/2023] [Indexed: 06/08/2023] Open
Abstract
Hyponatremia is primarily a water balance disorder associated with high morbidity and mortality. The pathophysiological mechanisms behind hyponatremia are multifactorial, and diagnosing and treating this disorder remains challenging. In this review, the classification, pathogenesis, and step-by-step management approaches for hyponatremia in patients with liver disease are described based on recent evidence. We summarize the five sequential steps of the traditional diagnostic approach: 1) confirm true hypotonic hyponatremia, 2) assess the severity of hyponatremia symptoms, 3) measure urine osmolality, 4) classify hyponatremia based on the urine sodium concentration and extracellular fluid status, and 5) rule out any coexisting endocrine disorder and renal failure. Distinct treatment strategies for hyponatremia in liver disease should be applied according to the symptoms, duration, and etiology of disease. Symptomatic hyponatremia requires immediate correction with 3% saline. Asymptomatic chronic hyponatremia in liver disease is prevalent and treatment plans should be individualized based on diagnosis. Treatment options for correcting hyponatremia in advanced liver disease may include water restriction; hypokalemia correction; and administration of vasopressin antagonists, albumin, and 3% saline. Safety concerns for patients with liver disease include a higher risk of osmotic demyelination syndrome.
Collapse
Affiliation(s)
- Ji Young Ryu
- Department of Internal Medicine, Hallym University Dongtan Sacred Heart Hospital, Hwaseong, Korea
| | - Seon Ha Baek
- Department of Internal Medicine, Hallym University Dongtan Sacred Heart Hospital, Hwaseong, Korea
| | - Sejoong Kim
- Department of Internal Medicine, Seoul University Bundang Hospital, Seongnam, Korea
- Center for Artificial Intelligence in Healthcare, Seoul University Bundang Hospital, Seongnam, Korea
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| |
Collapse
|
4
|
Tran-Guzman A, Moradian R, Walker C, Cui H, Corpuz M, Gonzalez I, Nguyen C, Meza P, Wen X, Culty M. Toxicity Profiles and Protective Effects of Antifreeze Proteins From Insect in Mammalian Models. Toxicol Lett 2022; 368:9-23. [PMID: 35901986 PMCID: PMC10174066 DOI: 10.1016/j.toxlet.2022.07.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 06/24/2022] [Accepted: 07/19/2022] [Indexed: 11/18/2022]
Abstract
Antifreeze proteins (AFPs), found in many cold-adapted organisms, can protect them from cold and freezing damages and have thus been considered as additional protectants in current cold tissue preservation solutions that generally include electrolytes, osmotic agents, colloids and antioxidants, to reduce the loss of tissue viability associated with cold-preservation. Due to the lack of toxicity profile studies on AFPs, their inclusion in cold preservation solutions has been a trial-and-error process limiting the development of AFPs' application in cold preservation. To assess the feasibility of translating the technology of AFPs for mammalian cell cold or cryopreservation, we determined the toxicity profile of two highly active beetle AFPs, DAFP1 and TmAFP, from Dendroides canadensis and Tenebrio molitor in this study. Toxicity was examined on a panel of representative mammalian cell lines including testicular spermatogonial stem cells and Leydig cells, macrophages, and hepatocytes. Treatments with DAFP1 and TmAFP at up to 500μg/mL for 48 and 72hours were safe in three of the cell lines, except for a 20% decrease in spermatogonia treated with TmAFP. However, both AFPs at 500μg/mL or below reduced hepatocyte viability by 20 to 40% at 48 and 72h. At 1000μg/mL, DAFP1 and TmAFP reduced viability in most cell lines. While spermatogonia and Leydig cell functions were not affected by 1000μg/mL DAFP1, this treatment induced inflammatory responses in macrophages. Adding 1000μg/ml DAFP1 to rat kidneys stored at 4°C for 48hours protected the tissues from cold-related damage, based on tissue morphology and gene and protein expression of two markers of kidney function. However, DAFP1 and TmAFP did not prevent the adverse effects of cold on kidneys over 72hours. Overall, DAFP1 is less toxic at high dose than TmAFP, and has potential for use in tissue preservation at doses up to 500μg/mL. However, careful consideration must be taken due to the proinflammatory potential of DAFP1 on macrophages at higher doses and the heighten susceptibility of hepatocytes to both AFPs.
Collapse
Affiliation(s)
- A Tran-Guzman
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - R Moradian
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - C Walker
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - H Cui
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - M Corpuz
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - I Gonzalez
- Department of Chemistry and Biochemistry, California State University, Los Angeles, Los Angeles, CA, USA
| | - C Nguyen
- Department of Chemistry and Biochemistry, California State University, Los Angeles, Los Angeles, CA, USA
| | - P Meza
- Department of Chemistry and Biochemistry, California State University, Los Angeles, Los Angeles, CA, USA
| | - X Wen
- Department of Chemistry and Biochemistry, California State University, Los Angeles, Los Angeles, CA, USA
| | - M Culty
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA.
| |
Collapse
|
5
|
Greene ES, Cauble R, Kadhim H, de Almeida Mallmann B, Gu I, Lee SO, Orlowski S, Dridi S. Protective effects of the phytogenic feed additive "comfort" on growth performance via modulation of hypothalamic feeding- and drinking-related neuropeptides in cyclic heat-stressed broilers. Domest Anim Endocrinol 2021; 74:106487. [PMID: 32861191 DOI: 10.1016/j.domaniend.2020.106487] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 04/12/2020] [Accepted: 04/13/2020] [Indexed: 12/14/2022]
Abstract
Identification of alternatives to antibiotics in livestock and poultry is necessary. Fueled by consumer preferences, phytogenic feed additives are increasingly used in the food system; however, their mode of action is not well defined. Here, we used broiler chickens, in which appetite and feeding behavior regulation are controlled by complex mechanisms, to determine the effect of the phytogenic feed additive "comfort" (PFA-C) as well as its underlying molecular mechanisms on growth performance in heat-stressed broiler chickens. Heat stress significantly increased birds' core body temperature, water intake, and the hypothalamic expression of heat shock protein (HSP) 70, whereas it decreased feed intake, BW, and woody breast incidence. Phytogenic feed additive "comfort" supplementation downregulated the hypothalamic expression of HSP70, reduced core body temperature, increased feed and water intake, and improved BW in HS broilers. At molecular levels, the effect of PFA-C on growth performance seemed to be mediated by modulation of hypothalamic expression of melanocortin receptor 2, arginine vasopressin, aquaporin 2, and sodium and potassium-transporting ATPase subunit beta 1 polypeptides. In summary, PFA-C supplementation ameliorates heat stress productivity losses via a potential cytoprotective effect, reduction of hypothalamic intracellular stress, and modulation of hypothalamic feeding- and drinking-related polypeptide expression.
Collapse
Affiliation(s)
- E S Greene
- Department of Poultry Science, Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - R Cauble
- Department of Animal Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - H Kadhim
- Department of Poultry Science, Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - B de Almeida Mallmann
- Department of Poultry Science, Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - I Gu
- Department of Food Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - S-O Lee
- Department of Food Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - S Orlowski
- Department of Poultry Science, Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - S Dridi
- Department of Poultry Science, Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA.
| |
Collapse
|
6
|
Yılmaz H, Özdemir Fİ, Ergenekon P, Özkan M. Affinity tag effect on the salt rejection potential of Halomonas elongata aquaporin incorporated in thin film nanocomposite membrane. Protein Expr Purif 2020; 173:105664. [PMID: 32380098 DOI: 10.1016/j.pep.2020.105664] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 05/03/2020] [Indexed: 11/18/2022]
Abstract
In this study, effect of affinity tags, Histidine (His) and Glutathione-S-Transferase (GST), on the activity of halophilic aquaporin was analyzed. The gene coding for H. elongata aquaporin was cloned into pET28a vector and expressed in E. coli BL21 successfully. Stopped flow light scattering measurements showed that His-tagged aquaporin is functional. The difference in the filtration parameters caused by affinity tags were determined by using thin film composite nano-filtration (NFC) membranes prepared with the aquaporins. At 100 mM salt concentration, water permeability (L/m2.h) and the % salt rejection of NFC membranes produced with the His-tagged aquaporin was found to be higher than that of the membrane with GST-tagged aquaporin. Salt rejection of His-tagged aquaporin-membrane was found to be 53% with a lower solute permeability value (B). Use of short affinity tag (His tag) for cloning resulted in higher solute rejection ability of TFC membranes prepared with H. elongata aquaporins.
Collapse
Affiliation(s)
- Hilal Yılmaz
- Gebze Technical University, Department of Environmental Engineering, 41400, Gebze Kocaeli, Turkey
| | - Fatma İnci Özdemir
- Gebze Technical University, Department of Molecular Biology and Genetics, 41400, Gebze Kocaeli, Turkey
| | - Pınar Ergenekon
- Gebze Technical University, Department of Environmental Engineering, 41400, Gebze Kocaeli, Turkey
| | - Melek Özkan
- Gebze Technical University, Department of Environmental Engineering, 41400, Gebze Kocaeli, Turkey.
| |
Collapse
|
7
|
Angiotensin II type 1 receptor-associated protein deficiency attenuates sirtuin1 expression in an immortalised human renal proximal tubule cell line. Sci Rep 2019; 9:16550. [PMID: 31719572 PMCID: PMC6851135 DOI: 10.1038/s41598-019-52566-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 10/17/2019] [Indexed: 11/08/2022] Open
Abstract
The proximal tubule is a particularly important site for ageing-related kidney damage. Sirtuin 1 (SIRT1), an NAD+ (nicotinamide adenine dinucleotide)-dependent deacetylase in the proximal tubule, may be involved in renal injury associated with ageing. However, the mechanisms of SIRT1 regulation remain to be elucidated. We recently reported that angiotensin II type 1 receptor (AT1R)-associated protein (ATRAP)-deficient mice displayed age-associated renal function decline and tubulointerstitial fibrosis. Our data showed that SIRT1 protein expression was reduced in ATRAP-deficient mice, although the relationship between ATRAP deficiency and age-associated renal fibrosis is still not fully understood. It is, therefore, necessary to investigate how ATRAP affects SIRT1 protein expression to resolve ageing-associated kidney dysfunction. Here, since ageing studies are inherently lengthy, we used an ex vivo model of the proximal tubule to determine the role of ATRAP in SIRT1 protein expression. We first generated a clonal immortalised human renal proximal tubule epithelial cell line (ciRPTEC) expressing AT1R and ATRAP. Using this cell line, we demonstrated that ATRAP knockdown reduced SIRT1 protein expression in the ciRPTEC but did not alter SIRT1 mRNA expression. Thus, ATRAP likely mediates SIRT1 protein abundance in ciRPTEC.
Collapse
|
8
|
Burton AG, Hopper K. Hyponatremia in dogs and cats. J Vet Emerg Crit Care (San Antonio) 2019; 29:461-471. [DOI: 10.1111/vec.12881] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/04/2017] [Accepted: 09/06/2017] [Indexed: 01/10/2023]
Affiliation(s)
| | - Kate Hopper
- Department of Veterinary Surgical and Radiological SciencesUniversity of California Davis CA
| |
Collapse
|
9
|
Hiratsuka K, Monkawa T, Akiyama T, Nakatake Y, Oda M, Goparaju SK, Kimura H, Chikazawa-Nohtomi N, Sato S, Ishiguro K, Yamaguchi S, Suzuki S, Morizane R, Ko SBH, Itoh H, Ko MSH. Induction of human pluripotent stem cells into kidney tissues by synthetic mRNAs encoding transcription factors. Sci Rep 2019; 9:913. [PMID: 30696889 PMCID: PMC6351687 DOI: 10.1038/s41598-018-37485-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 12/05/2018] [Indexed: 01/10/2023] Open
Abstract
The derivation of kidney tissues from human pluripotent stem cells (hPSCs) and its application for replacement therapy in end-stage renal disease have been widely discussed. Here we report that consecutive transfections of two sets of synthetic mRNAs encoding transcription factors can induce rapid and efficient differentiation of hPSCs into kidney tissues, termed induced nephron-like organoids (iNephLOs). The first set - FIGLA, PITX2, ASCL1 and TFAP2C, differentiated hPSCs into SIX2+SALL1+ nephron progenitor cells with 92% efficiency within 2 days. Subsequently, the second set - HNF1A, GATA3, GATA1 and EMX2, differentiated these cells into PAX8+LHX1+ pretubular aggregates in another 2 days. Further culture in both 2-dimensional and 3-dimensional conditions produced iNephLOs containing cells characterized as podocytes, proximal tubules, and distal tubules in an additional 10 days. Global gene expression profiles showed similarities between iNephLOs and the human adult kidney, suggesting possible uses of iNephLOs as in vitro models for kidneys.
Collapse
Affiliation(s)
- Ken Hiratsuka
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
- Department of Nephrology, Endocrinology, and Metabolism, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Toshiaki Monkawa
- Department of Nephrology, Endocrinology, and Metabolism, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
- Medical Education Center, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Tomohiko Akiyama
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Yuhki Nakatake
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Mayumi Oda
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Sravan Kumar Goparaju
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Hiromi Kimura
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Nana Chikazawa-Nohtomi
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Saeko Sato
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Keiichiro Ishiguro
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
- Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto, 860-0811, Japan
| | - Shintaro Yamaguchi
- Department of Nephrology, Endocrinology, and Metabolism, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Sayuri Suzuki
- Department of Nephrology, Endocrinology, and Metabolism, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Ryuji Morizane
- Department of Nephrology, Endocrinology, and Metabolism, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
- Renal Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
- Harvard Stem Cell Institute, Cambridge, Massachusetts, USA
| | - Shigeru B H Ko
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Hiroshi Itoh
- Department of Nephrology, Endocrinology, and Metabolism, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Minoru S H Ko
- Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan.
| |
Collapse
|
10
|
Bryant JL, Guda PR, Ray S, Asemu G, Sagi AR, Mubariz F, Arvas MI, Khalid OS, Shukla V, Nimmagadda VKC, Makar TK. Renal aquaporin-4 associated pathology in TG-26 mice. Exp Mol Pathol 2018; 104:239-249. [PMID: 29608911 DOI: 10.1016/j.yexmp.2018.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 03/29/2018] [Indexed: 12/15/2022]
Abstract
Human immunodeficiency virus-associated nephropathy (HIVAN) is a leading cause of end-stage renal disease in HIV patients, which is characterized by glomerulosclerosis and renal tubular dysfunction. Aquaporin-4 (AQP-4) is a membrane bound water channel protein that plays a distinct role in water reabsorption from renal tubular fluid. It has been proven that failure of AQP-4 insertion into the renal tubular membrane leads to renal dysfunction. However, the role of AQP-4 in HIVAN is unclear. We hypothesize that impaired water reabsorption leads to renal injury in HIVAN, where AQP-4 plays a crucial role. Renal function is assessed by urinary protein and serum blood urea nitrogen (BUN). Kidneys from HIV Transgenic (TG26) mice (HIVAN animal model) were compared to wild type mice by immunostaining, immunoblotting and quantitative RT-PCR. TG26 mice had increased proteinuria and BUN. We found decreased AQP-4 levels in the renal medulla, increased endothelin-1, endothelin receptor A and reduced Sirtuin1 (SIRT-1) levels in TG26 mice. Also, oxidative and endoplasmic reticulum stress was enhanced in kidneys of TG26 mice. We provide the first evidence that AQP-4 is inhibited due to induction of HIV associated stress in the kidneys of TG26 mice which limits water reabsorption in the kidney which may be one of the cause associated with HIVAN, impairing kidney physiology. AQP-4 dysregulation in TG26 mice suggests that similar changes may occur in HIVAN patients. This work may identify new therapeutic targets to be evaluated in HIVAN.
Collapse
Affiliation(s)
- Joseph L Bryant
- Institute of Human Virology, University of Maryland, Baltimore, MD, United States
| | | | - Sugata Ray
- Department of Neurology, University of Maryland, Baltimore, MD, United States
| | - Girma Asemu
- Institute of Human Virology, University of Maryland, Baltimore, MD, United States
| | - Avinash R Sagi
- Department of Neurology, University of Maryland, Baltimore, MD, United States
| | - Fahad Mubariz
- Department of Neurology, University of Maryland, Baltimore, MD, United States
| | - Muhammed I Arvas
- Department of Neurology, University of Maryland, Baltimore, MD, United States
| | - Omar S Khalid
- Department of Neurology, University of Maryland, Baltimore, MD, United States
| | - Vivek Shukla
- Department of Neurology, University of Maryland, Baltimore, MD, United States
| | - Vamshi K C Nimmagadda
- Department of Neurology, University of Maryland, Baltimore, MD, United States; VA Medical Center, Baltimore, MD, United States
| | - Tapas K Makar
- Department of Neurology, University of Maryland, Baltimore, MD, United States; VA Medical Center, Baltimore, MD, United States.
| |
Collapse
|
11
|
Lei L, Huang M, Su L, Xie D, Mamuya FA, Ham O, Tsuji K, Păunescu TG, Yang B, Lu HAJ. Manganese promotes intracellular accumulation of AQP2 via modulating F-actin polymerization and reduces urinary concentration in mice. Am J Physiol Renal Physiol 2017; 314:F306-F316. [PMID: 29046300 DOI: 10.1152/ajprenal.00391.2017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Aquaporin-2 (AQP2) is a water channel protein expressed in principal cells (PCs) of the kidney collecting ducts (CDs) and plays a critical role in mediating water reabsorption and urine concentration. AQP2 undergoes both regulated trafficking mediated by vasopressin (VP) and constitutive recycling, which is independent of VP. For both pathways, actin cytoskeletal dynamics is a key determinant of AQP2 trafficking. We report here that manganese chloride (MnCl2) is a novel and potent regulator of AQP2 trafficking in cultured cells and in the kidney. MnCl2 treatment promoted internalization and intracellular accumulation of AQP2. The effect of MnCl2 on the intracellular accumulation of AQP2 was associated with activation of RhoA and actin polymerization without modification of AQP2 phosphorylation. Although the level of total and phosphorylated AQP2 did not change, MnCl2 treatment impeded VP-induced phosphorylation of AQP2 at its serine-256, -264, and -269 residues and dephosphorylation at serine 261. In addition, MnCl2 significantly promoted F-actin polymerization along with downregulation of RhoA activity and prevented VP-induced membrane accumulation of AQP2. Finally, MnCl2 treatment in mice resulted in significant polyuria and reduced urinary concentration, likely due to intracellular relocation of AQP2 in the PCs of kidney CDs. More importantly, the reduced urinary concentration caused by MnCl2 treatment in animals was not corrected by VP. In summary, our study identified a novel effect of MnCl2 on AQP2 trafficking through modifying RhoA activity and actin polymerization and uncovered its potent impact on water diuresis in vivo.
Collapse
Affiliation(s)
- Lei Lei
- Department of Pharmacology, School of Basic Medical Sciences, Peking University , Beijing , People's Republic of China.,Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts
| | - Ming Huang
- Department of Pharmacology, School of Basic Medical Sciences, Peking University , Beijing , People's Republic of China.,Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts
| | - Limin Su
- Department of Pharmacology, School of Basic Medical Sciences, Peking University , Beijing , People's Republic of China.,Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts
| | - Dongping Xie
- Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts
| | - Fahmy A Mamuya
- Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts.,Harvard Medical School , Boston, Massachusetts
| | - Onju Ham
- Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts.,Harvard Medical School , Boston, Massachusetts
| | - Kenji Tsuji
- Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts.,Harvard Medical School , Boston, Massachusetts
| | - Teodor G Păunescu
- Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts.,Harvard Medical School , Boston, Massachusetts
| | - Baoxue Yang
- Department of Pharmacology, School of Basic Medical Sciences, Peking University , Beijing , People's Republic of China
| | - Hua A Jenny Lu
- Program in Membrane Biology, Center for Systems Biology, and Division of Nephrology, Department of Medicine, Massachusetts General Hospital , Boston, Massachusetts.,Harvard Medical School , Boston, Massachusetts
| |
Collapse
|
12
|
Yamaguchi S, Morizane R, Homma K, Monkawa T, Suzuki S, Fujii S, Koda M, Hiratsuka K, Yamashita M, Yoshida T, Wakino S, Hayashi K, Sasaki J, Hori S, Itoh H. Generation of kidney tubular organoids from human pluripotent stem cells. Sci Rep 2016; 6:38353. [PMID: 27982115 PMCID: PMC5159864 DOI: 10.1038/srep38353] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 11/08/2016] [Indexed: 12/12/2022] Open
Abstract
Recent advances in stem cell research have resulted in methods to generate kidney organoids from human pluripotent stem cells (hPSCs), which contain cells of multiple lineages including nephron epithelial cells. Methods to purify specific types of cells from differentiated hPSCs, however, have not been established well. For bioengineering, cell transplantation, and disease modeling, it would be useful to establish those methods to obtain pure populations of specific types of kidney cells. Here, we report a simple two-step differentiation protocol to generate kidney tubular organoids from hPSCs with direct purification of KSP (kidney specific protein)-positive cells using anti-KSP antibody. We first differentiated hPSCs into mesoderm cells using a glycogen synthase kinase-3β inhibitor for 3 days, then cultured cells in renal epithelial growth medium to induce KSP+ cells. We purified KSP+ cells using flow cytometry with anti-KSP antibody, which exhibited characteristics of all segments of kidney tubular cells and cultured KSP+ cells in 3D Matrigel, which formed tubular organoids in vitro. The formation of tubular organoids by KSP+ cells induced the acquisition of functional kidney tubules. KSP+ cells also allowed for the generation of chimeric kidney cultures in which human cells self-assembled into 3D tubular structures in combination with mouse embryonic kidney cells.
Collapse
Affiliation(s)
- Shintaro Yamaguchi
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Ryuji Morizane
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.,Renal Division, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA.,Department of Medicine, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA.,Harvard Stem Cell Institute, 7 Divinity Ave, Cambridge, MA 02138, USA
| | - Koichiro Homma
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.,Emergency and Critical Care Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Toshiaki Monkawa
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.,Medical Education Center, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Sayuri Suzuki
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Shizuka Fujii
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Muneaki Koda
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Ken Hiratsuka
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Maho Yamashita
- Apheresis and Dialysis Center, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Tadashi Yoshida
- Apheresis and Dialysis Center, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Shu Wakino
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Koichi Hayashi
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Junichi Sasaki
- Emergency and Critical Care Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Shingo Hori
- Emergency and Critical Care Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Hiroshi Itoh
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| |
Collapse
|
13
|
Bernal A, Mahía J, Puerto A. Animal models of Central Diabetes Insipidus: Human relevance of acquired beyond hereditary syndromes and the role of oxytocin. Neurosci Biobehav Rev 2016; 66:1-14. [DOI: 10.1016/j.neubiorev.2016.02.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 02/23/2016] [Accepted: 02/27/2016] [Indexed: 12/18/2022]
|
14
|
Abstract
Disorders of sodium and water metabolism are frequently encountered in hospitalized patients. Hyponatremia in critically ill patients can cause significant morbidity and mortality. Inappropriate treatment of hyponatremia can add to the problem. The diagnosis and management of salt and water abnormalities in critically ill patients is often challenging. The increasing knowledge about aquaporins and the role of vasopressin in water metabolism has enhanced our understanding of these disorders. The authors have outlined the general approach to the diagnosis and management of hyponatremia. A systematic approach by clinicians, using a detailed history, physical examination, and relevant diagnostic tests, will assist in efficient management of salt and water problems.
Collapse
Affiliation(s)
- T J Vachharajani
- Louisiana State University Health Sciences Center and Overton Brooks Veterans Affairs Medical Center, Shreveport, LA 71130, USA
| | | | | |
Collapse
|
15
|
Li J, Zhang L, Jiang Z, He X, Zhang L, Xu M. Expression of Renal Aquaporins in Aristolochic Acid I and Aristolactam I-Induced Nephrotoxicity. Nephron Clin Pract 2016; 133:213-21. [PMID: 27352112 DOI: 10.1159/000446854] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/13/2016] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Exposure to aristolochic acid (AA) can cause AA nephropathy, which is characterized by extensive proximal tubular damage and polyuria. METHODS To test the hypothesis that polyuria might be induced by altered regulation of aquaporins (AQPs) in the kidney, different doses of AA-I or aristolactam I (AL-I) were administered intraperitoneally to Sprague-Dawley rats, and urine, blood, and kidney samples were analyzed. In addition, AQP1, AQP2, AQP4 and AQP6 expression in the kidney were determined. RESULTS The results showed dose-dependent proximal tubular damage and polyuria in the AA-I- and AL-I-treated groups, and the nephrotoxicity of AL-I was higher than that of AA-I. The expression of renal AQP1, AQP2 and AQP4, but not AQP6 were significantly inhibited by AA-I and AL-I. Comparison of the inhibition potencies of AA-I and AL-I showed that AL-I was a stronger inhibitor of AQP1 expression than AA-I, while there was no difference in their effects on AQP2 and AQP4. CONCLUSION These results suggested that AA induced renal damage and polyuria were associated with a specific decrease in the expression of renal AQP1 AQP2 and AQP4, and AL-I showed higher nephrotoxicity than AA-I, which might be attributable to the differences in their inhibition of AQP1.
Collapse
Affiliation(s)
- Ji Li
- Department of Clinical Pharmacy, School of Basic Medicine and Clinical Pharmacy, Nanjing, PR China
| | | | | | | | | | | |
Collapse
|
16
|
Soluble (pro)renin receptor via β-catenin enhances urine concentration capability as a target of liver X receptor. Proc Natl Acad Sci U S A 2016; 113:E1898-906. [PMID: 26984496 DOI: 10.1073/pnas.1602397113] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The extracellular domain of the (pro)renin receptor (PRR) is cleaved to produce a soluble (pro)renin receptor (sPRR) that is detected in biological fluid and elevated under certain pathological conditions. The present study was performed to define the antidiuretic action of sPRR and its potential interaction with liver X receptors (LXRs), which are known regulators of urine-concentrating capability. Water deprivation consistently elevated urinary sPRR excretion in mice and humans. A template-based algorithm for protein-protein interaction predicted the interaction between sPRR and frizzled-8 (FZD8), which subsequently was confirmed by coimmunoprecipitation. A recombinant histidine-tagged sPRR (sPRR-His) in the nanomolar range induced a remarkable increase in the abundance of renal aquaporin 2 (AQP2) protein in primary rat inner medullary collecting duct cells. The AQP2 up-regulation relied on sequential activation of FZD8-dependent β-catenin signaling and cAMP-PKA pathways. Inhibition of FZD8 or tankyrase in rats induced polyuria, polydipsia, and hyperosmotic urine. Administration of sPRR-His alleviated the symptoms of diabetes insipidus induced in mice by vasopressin 2 receptor antagonism. Administration of the LXR agonist TO901317 to C57/BL6 mice induced polyuria and suppressed renal AQP2 expression associated with reduced renal PRR expression and urinary sPRR excretion. Administration of sPRR-His reversed most of the effects of TO901317. In cultured collecting duct cells, TO901317 suppressed PRR protein expression, sPRR release, and PRR transcriptional activity. Overall we demonstrate, for the first time to our knowledge, that sPRR exerts antidiuretic action via FZD8-dependent stimulation of AQP2 expression and that inhibition of this pathway contributes to the pathogenesis of diabetes insipidus induced by LXR agonism.
Collapse
|
17
|
Wang L, Zhang Y, Wu X, Yu G. Aquaporins: New Targets for Cancer Therapy. Technol Cancer Res Treat 2015; 15:821-828. [PMID: 26438607 DOI: 10.1177/1533034615607693] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 08/17/2015] [Indexed: 12/12/2022] Open
Abstract
Aquaporins are a family of integral membrane proteins that are expressed in all living organisms and play vital roles in transcellular and transepithelial water movement. Cell viability and motility are critical for progression of cancer. Cell survival requires the suitable concentration of water and solutes. The balance is largely maintained by aquaporins whose major function is the transport of water and small solutes across the plasma membrane. The important role of aquaporins has received more and more attention in the recent years. A number of recent studies have revealed that aquaporins may be involved in cell migration and angiogenesis. This review will highlight the expression of aquaporins in different malignant neoplasms. Remarkably, we will summarize the influence of drugs on aquaporins, not only the traditional Chinese medicine but also the Western medicine. Therapeutic targeting of aquaporins may thus be advantageous for blocking the mechanism common for a number of key cancer phenotypes.
Collapse
Affiliation(s)
- Liping Wang
- Clinical Oncology Department, Weifang People's Hospital, Kuiwen, Weifang, China
| | - Yixiang Zhang
- Respiratory Medicine Department, Second People's Hospital of Weifang, Kuiwen, Weifang, China
| | - Xiongzhi Wu
- Patient Department, Tianjin Medical University Cancer Institute and Hospital, Hexi, Tianjin, China
| | - Guohua Yu
- Clinical Oncology Department, Weifang People's Hospital, Kuiwen, Weifang, China
| |
Collapse
|
18
|
Chen J, Wu L, Wang Y, Yin J, Li X, Wang Z, Li H, Zou T, Qian C, Li C, Zhang W, Zhou H, Liu Z. Effect of transporter and DNA repair gene polymorphisms to lung cancer chemotherapy toxicity. Tumour Biol 2015; 37:2275-84. [PMID: 26358256 DOI: 10.1007/s13277-015-4048-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 09/02/2015] [Indexed: 11/26/2022] Open
Abstract
Lung cancer is the first leading cause of cancer deaths. Chemotherapy toxicity is one of factors that limited the efficacy of platinum-based chemotherapy in lung cancer patients. Transporters and DNA repair genes play critical roles in occurrence of platinum-based chemotherapy toxicity. To investigate the relationships between transporter and DNA repair gene polymorphisms and platinum-based chemotherapy toxicity in lung cancer patients, we selected 60 polymorphisms in 14 transporters and DNA repair genes. The polymorphisms were genotyped in 317 lung cancer patients by Sequenom MassARRAY. Logistic regression was performed to estimate the association of toxicity outcome with the polymorphisms by PLINK. Our results showed that polymorphisms of SLC2A1 (rs3738514, rs4658, rs841844) were significantly related to overall toxicity. XRCC5 (rs1051685, rs6941) and AQP2 (10875989, rs3759125) polymorphisms were associated with hematologic toxicity. AQP2 polymorphisms (rs461872, rs7305534) were correlated with gastrointestinal toxicity. In conclusion, genotypes of these genes may be used to predict the platinum-based chemotherapy toxicity in lung cancer patients.
Collapse
Affiliation(s)
- Juan Chen
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China
- Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha, 410078, People's Republic of China
- Hunan Province Cooperation Innovation Center for Molecular Target New Drug Study, Hengyang, 421001, People's Republic of China
| | - Lin Wu
- The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, 410014, People's Republic of China
| | - Ying Wang
- The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, 410014, People's Republic of China
| | - Jiye Yin
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China
- Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha, 410078, People's Republic of China
- Hunan Province Cooperation Innovation Center for Molecular Target New Drug Study, Hengyang, 421001, People's Republic of China
| | - Xiangping Li
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China
- Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha, 410078, People's Republic of China
| | - Zhan Wang
- Department of Oncology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China
| | - Huihua Li
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Ting Zou
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China
- Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha, 410078, People's Republic of China
| | - Chenyue Qian
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China
- Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha, 410078, People's Republic of China
| | - Chuntian Li
- Department of Radiotherapy, PLA 463 Hospital, Shenyang, 110042, People's Republic of China
| | - Wei Zhang
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China
- Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha, 410078, People's Republic of China
- Hunan Province Cooperation Innovation Center for Molecular Target New Drug Study, Hengyang, 421001, People's Republic of China
| | - Honghao Zhou
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China
- Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha, 410078, People's Republic of China
- Hunan Province Cooperation Innovation Center for Molecular Target New Drug Study, Hengyang, 421001, People's Republic of China
| | - Zhaoqian Liu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China.
- Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha, 410078, People's Republic of China.
- Hunan Province Cooperation Innovation Center for Molecular Target New Drug Study, Hengyang, 421001, People's Republic of China.
| |
Collapse
|
19
|
Castellar A, Bertoli PC, Galdino LH, Domeniconi RF, Cruz-Neto AP. Differences in physiological traits associated with water balance among rodents, and their relationship to tolerance of habitat fragmentation. ACTA ACUST UNITED AC 2015; 323:731-744. [PMID: 26349625 DOI: 10.1002/jez.1966] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 07/27/2015] [Accepted: 08/11/2015] [Indexed: 11/06/2022]
Abstract
Physiological concepts and tools can help us to understand why organisms and populations respond to habitat fragmentation in the way they do, and allow us to determine the mechanisms or individual characteristics underlying this differential sensitivity. Here, we examine food intake, relative medullary thickness and distribution/expression of water channel aquaporin-1 in three species of South American rodents that have been reported to have different levels of tolerance to habitat fragmentation (Akodon montensis, Oligoryzomys nigripes, and Euryoryzomys russatus), using a classic water deprivation experiment to assess their abilities to cope with water shortage. We believe the mechanisms underlying this differential sensitivity are related to the organisms' capacities to maintain water balance, and therefore the species more tolerant to habitat fragmentation (A. montensis and O. nigripes) should have a higher capacity to maintain water balance. We found that A. montensis and O. nigripes were more tolerant to water deprivation than E. russatus, and this difference appears to be unrelated to differences in food ingestion rate. O. nigripes showed the highest values for RMT, followed by A. montensis and E. russatus. However all species showed RMT values that were 2.2% to 14.1% below the lower prediction limit when compared to other rodents through allometric relationships. Water deprivation seems to trigger changes in the distribution of aquaporin-1, mostly for O. nigripes and E. russatus, which may contribute to water balance maintenance. Our data suggest that these intrinsic physiological differences among these species could provide a mechanism for their differential tolerance of habitat fragmentation. J. Exp. Zool. 323A: 731-744, 2015. © 2015 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Alexandre Castellar
- Department of Zoology, Biosciences Institute, UNESP - Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil
| | - Paula Custódio Bertoli
- Department of Zoology, Biosciences Institute, UNESP - Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil
| | | | - Raquel Fantin Domeniconi
- Department of Anatomy, Biosciences Institute, UNESP - Universidade Estadual Paulista, Botucatu, São Paulo, Brazil
| | - Ariovaldo Pereira Cruz-Neto
- Department of Zoology, Biosciences Institute, UNESP - Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil
| |
Collapse
|
20
|
John S, Thuluvath PJ. Hyponatremia in cirrhosis: Pathophysiology and management. World J Gastroenterol 2015; 21:3197-205. [PMID: 25805925 PMCID: PMC4363748 DOI: 10.3748/wjg.v21.i11.3197] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/02/2014] [Accepted: 01/30/2015] [Indexed: 02/06/2023] Open
Abstract
Hyponatremia is frequently seen in patients with ascites secondary to advanced cirrhosis and portal hypertension. The development of ascites in patients with cirrhosis is multi-factorial. Portal hypertension and the associated systemic vasodilation lead to activation of the sodium-retaining neurohumoral mechanisms which include the renin-angiotensin-aldosterone system, sympathetic nervous system and antidiuretic hormone (ADH). The net effect is the avid retention of sodium and water to compensate for the low effective circulatory volume resulting in the development of ascites. Although not apparent in the early stages of cirrhosis, the progression of cirrhosis and ascites leads to impairment of the kidneys to eliminate solute- free water. This leads to additional compensatory mechanisms including non-osmotic secretion of ADH, also known as arginine vasopressin, further worsening excess water retention and thereby hyponatremia. Hyponatremia is associated with increased morbidity and mortality in patients with cirrhosis, and is an important prognostic marker both before and after liver transplant. The management of hyponatremia in this setting is a challenge as conventional therapy for hyponatremia including fluid restriction and loop diuretics are frequently inefficacious. In this review, we discuss the pathophysiology and various treatment modalities, including selective vasopressin receptor antagonists, for the management of hyponatremia in patients with cirrhosis.
Collapse
|
21
|
Pohl M, Shan Q, Petsch T, Styp-Rekowska B, Matthey P, Bleich M, Bachmann S, Theilig F. Short-term functional adaptation of aquaporin-1 surface expression in the proximal tubule, a component of glomerulotubular balance. J Am Soc Nephrol 2014; 26:1269-78. [PMID: 25270072 DOI: 10.1681/asn.2014020148] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 07/22/2014] [Indexed: 11/03/2022] Open
Abstract
Transepithelial water flow across the renal proximal tubule is mediated predominantly by aquaporin-1 (AQP1). Along this nephron segment, luminal delivery and transepithelial reabsorption are directly coupled, a phenomenon called glomerulotubular balance. We hypothesized that the surface expression of AQP1 is regulated by fluid shear stress, contributing to this effect. Consistent with this finding, we found that the abundance of AQP1 in brush border apical and basolateral membranes was augmented >2-fold by increasing luminal perfusion rates in isolated, microperfused proximal tubules for 15 minutes. Mouse kidneys with diminished endocytosis caused by a conditional deletion of megalin or the chloride channel ClC-5 had constitutively enhanced AQP1 abundance in the proximal tubule brush border membrane. In AQP1-transfected, cultured proximal tubule cells, fluid shear stress or the addition of cyclic nucleotides enhanced AQP1 surface expression and concomitantly diminished its ubiquitination. These effects were also associated with an elevated osmotic water permeability. In sum, we have shown that luminal surface expression of AQP1 in the proximal tubule brush border membrane is regulated in response to flow. Cellular trafficking, endocytosis, an intact endosomal compartment, and controlled protein stability are the likely prerequisites for AQP1 activation by enhanced tubular fluid shear stress, serving to maintain glomerulotubular balance.
Collapse
Affiliation(s)
- Marcus Pohl
- Institute of Anatomy, Charité Universitätsmedizin, Berlin, Germany
| | - Qixian Shan
- Institute of Physiology, Kiel University, Kiel, Germany
| | - Thomas Petsch
- Institute of Anatomy, Charité Universitätsmedizin, Berlin, Germany
| | | | - Patricia Matthey
- Institute of Anatomy, Department of Medicine, University of Fribourg, Fribourg, Switzerland
| | - Markus Bleich
- Institute of Physiology, Kiel University, Kiel, Germany
| | | | - Franziska Theilig
- Institute of Anatomy, Charité Universitätsmedizin, Berlin, Germany; Institute of Anatomy, Department of Medicine, University of Fribourg, Fribourg, Switzerland
| |
Collapse
|
22
|
Wang Y, Yin JY, Li XP, Chen J, Qian CY, Zheng Y, Fu YL, Chen ZY, Zhou HH, Liu ZQ. The association of transporter genes polymorphisms and lung cancer chemotherapy response. PLoS One 2014; 9:e91967. [PMID: 24643204 PMCID: PMC3958404 DOI: 10.1371/journal.pone.0091967] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 02/16/2014] [Indexed: 01/11/2023] Open
Abstract
Lung cancer is one of the most common cancers and is the leading cause of death worldwide. Platinum-based chemotherapy is the main treatment method in lung cancer patients. Our previous studies indicated that single nucleotide polymorphisms (SNPs) in some transporter genes played important role in platinum-based chemotherapy efficacy. The aim of this study was to investigate the association of SNPs in transporter genes and platinum-based chemotherapy efficacy. The main polymorphisms on transporters OCT2, LRP, AQP2, AQP9 and TMEM205 genes were genotyped in 338 lung cancer patients. The rs195854 in genotypic model, rs896412 in genotypic and recessive models for all subjects showed significant association with chemotherapy response. In stratification analysis, TMEM205 rs896412, OCT2 rs1869641 and rs195854, AQP9 rs1516400 and AQP2 rs7314734 showed significant relation to chemotherapy response. In conclusion, the genetic polymorphisms in OCT2, AQP2, AQP9 and TMEM205 may contribute to chemotherapy response in lung cancer patients.
Collapse
Affiliation(s)
- Ying Wang
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, P. R. China
| | - Ji-Ye Yin
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, P. R. China
| | - Xiang-Ping Li
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, P. R. China
| | - Juan Chen
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, P. R. China
| | - Chen-Yue Qian
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, P. R. China
| | - Yi Zheng
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, P. R. China
| | - Yi-Lan Fu
- The Affiliated Cancer Hospital of XiangYa School of Medicine, Central South University, Changsha, Hunan, P. R. China
| | - Zi-Yu Chen
- The Affiliated Cancer Hospital of XiangYa School of Medicine, Central South University, Changsha, Hunan, P. R. China
| | - Hong-Hao Zhou
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, P. R. China
| | - Zhao-Qian Liu
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, P. R. China
- * E-mail:
| |
Collapse
|
23
|
Kawaguchi-Suzuki M, Frye RF. Current clinical evidence on pioglitazone pharmacogenomics. Front Pharmacol 2013; 4:147. [PMID: 24324437 PMCID: PMC3840328 DOI: 10.3389/fphar.2013.00147] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 11/07/2013] [Indexed: 12/31/2022] Open
Abstract
Pioglitazone is the most widely used thiazolidinedione and acts as an insulin-sensitizer through activation of the Peroxisome Proliferator-Activated Receptor-γ (PPARγ). Pioglitazone is approved for use in the management of type 2 diabetes mellitus (T2DM), but its use in other therapeutic areas is increasing due to pleiotropic effects. In this hypothesis article, the current clinical evidence on pioglitazone pharmacogenomics is summarized and related to variability in pioglitazone response. How genetic variation in the human genome affects the pharmacokinetics and pharmacodynamics of pioglitazone was examined. For pharmacodynamic effects, hypoglycemic and anti-atherosclerotic effects, risks of fracture or edema, and the increase in body mass index in response to pioglitazone based on genotype were examined. The genes CYP2C8 and PPARG are the most extensively studied to date and selected polymorphisms contribute to respective variability in pioglitazone pharmacokinetics and pharmacodynamics. We hypothesized that genetic variation in pioglitazone pathway genes contributes meaningfully to the clinically observed variability in drug response. To test the hypothesis that genetic variation in PPARG associates with variability in pioglitazone response, we conducted a meta-analysis to synthesize the currently available data on the PPARG p.Pro12Ala polymorphism. The results showed that PPARG 12Ala carriers had a more favorable change in fasting blood glucose from baseline as compared to patients with the wild-type Pro12Pro genotype (p = 0.018). Unfortunately, findings for many other genes lack replication in independent cohorts to confirm association; further studies are needed. Also, the biological functionality of these polymorphisms is unknown. Based on current evidence, we propose that pharmacogenomics may provide an important tool to individualize pioglitazone therapy and better optimize therapy in patients with T2DM or other conditions for which pioglitazone is being used.
Collapse
Affiliation(s)
- Marina Kawaguchi-Suzuki
- Department of Pharmacotherapy and Translational Research, Center for Pharmacogenomics, College of Pharmacy, University of Florida Gainesville, FL, USA
| | | |
Collapse
|
24
|
Christensen EI, Wagner CA, Kaissling B. Uriniferous tubule: structural and functional organization. Compr Physiol 2013; 2:805-61. [PMID: 23961562 DOI: 10.1002/cphy.c100073] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The uriniferous tubule is divided into the proximal tubule, the intermediate (thin) tubule, the distal tubule and the collecting duct. The present chapter is based on the chapters by Maunsbach and Christensen on the proximal tubule, and by Kaissling and Kriz on the distal tubule and collecting duct in the 1992 edition of the Handbook of Physiology, Renal Physiology. It describes the fine structure (light and electron microscopy) of the entire mammalian uriniferous tubule, mainly in rats, mice, and rabbits. The structural data are complemented by recent data on the location of the major transport- and transport-regulating proteins, revealed by morphological means(immunohistochemistry, immunofluorescence, and/or mRNA in situ hybridization). The structural differences along the uriniferous tubule strictly coincide with the distribution of the major luminal and basolateral transport proteins and receptors and both together provide the basis for the subdivision of the uriniferous tubule into functional subunits. Data on structural adaptation to defined functional changes in vivo and to genetical alterations of specified proteins involved in transepithelial transport importantly deepen our comprehension of the correlation of structure and function in the kidney, of the role of each segment or cell type in the overall renal function,and our understanding of renal pathophysiology.
Collapse
|
25
|
Day RE, Kitchen P, Owen DS, Bland C, Marshall L, Conner AC, Bill RM, Conner MT. Human aquaporins: regulators of transcellular water flow. Biochim Biophys Acta Gen Subj 2013; 1840:1492-506. [PMID: 24090884 DOI: 10.1016/j.bbagen.2013.09.033] [Citation(s) in RCA: 190] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 09/19/2013] [Accepted: 09/23/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND Emerging evidence supports the view that (AQP) aquaporin water channels are regulators of transcellular water flow. Consistent with their expression in most tissues, AQPs are associated with diverse physiological and pathophysiological processes. SCOPE OF REVIEW AQP knockout studies suggest that the regulatory role of AQPs, rather than their action as passive channels, is their critical function. Transport through all AQPs occurs by a common passive mechanism, but their regulation and cellular distribution varies significantly depending on cell and tissue type; the role of AQPs in cell volume regulation (CVR) is particularly notable. This review examines the regulatory role of AQPs in transcellular water flow, especially in CVR. We focus on key systems of the human body, encompassing processes as diverse as urine concentration in the kidney to clearance of brain oedema. MAJOR CONCLUSIONS AQPs are crucial for the regulation of water homeostasis, providing selective pores for the rapid movement of water across diverse cell membranes and playing regulatory roles in CVR. Gating mechanisms have been proposed for human AQPs, but have only been reported for plant and microbial AQPs. Consequently, it is likely that the distribution and abundance of AQPs in a particular membrane is the determinant of membrane water permeability and a regulator of transcellular water flow. GENERAL SIGNIFICANCE Elucidating the mechanisms that regulate transcellular water flow will improve our understanding of the human body in health and disease. The central role of specific AQPs in regulating water homeostasis will provide routes to a range of novel therapies. This article is part of a Special Issue entitled Aquaporins.
Collapse
Affiliation(s)
- Rebecca E Day
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield S1 1WB, UK
| | - Philip Kitchen
- Molecular Organisation and Assembly in Cells Doctoral Training Centre, University of Warwick, Coventry CV4 7AL, UK
| | - David S Owen
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield S1 1WB, UK
| | - Charlotte Bland
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
| | - Lindsay Marshall
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
| | - Alex C Conner
- School of Clinical and Experimental Medicine, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
| | - Roslyn M Bill
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK.
| | - Matthew T Conner
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield S1 1WB, UK.
| |
Collapse
|
26
|
Van Wart SA, Shoaf SE, Mallikaarjun S, Mager DE. Population pharmacokinetics of tolvaptan in healthy subjects and patients with hyponatremia secondary to congestive heart failure or hepatic cirrhosis. Biopharm Drug Dispos 2013; 34:336-47. [PMID: 23794414 DOI: 10.1002/bdd.1849] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 06/10/2013] [Accepted: 06/20/2013] [Indexed: 12/31/2022]
Abstract
Tolvaptan is a selective V2 -receptor antagonist used to treat hypervolemic and euvolemic hyponatremia. A population pharmacokinetic (PK) analysis was performed for tolvaptan in NONMEM® based upon data obtained from three trials conducted in 93 healthy subjects and six trials conducted in 628 congestive heart failure (CHF) patients or 24 hepatic cirrhosis patients receiving oral tolvaptan (5 to 240 mg). A two-compartment model with first-order absorption and elimination best described tolvaptan PK. Relative oral bioavailability was modeled relative to 100% for a 30 mg dose and ranged from 79.4% to 122%. Body weight and the impact of CHF or hepatic cirrhosis relative to healthy subjects were statistically significant (p < 0.001) predictors of both the apparent oral clearance (CL/F) and apparent central volume of distribution (Vc /F). The CL/F was reduced to 58.2% for New York Heart Association (NYHA) Class 1 or 2 CHF, 45.5% for NYHA Class 3 or 4 CHF, and 58.0% for hepatic cirrhosis relative to healthy subjects. Vc /F was reduced to 59.9% for NYHA Class 1 or 2 CHF and 51.3% for NYHA Class 3 or 4 CHF, and was 64.8% larger for severe hepatic cirrhosis (Child-Pugh score ≥ 10) relative to healthy subjects. A slight additional decrease in CL/F of 18.3% was also detected for patients with moderate hyponatremia (serum sodium of 115-130 mEq/l) after adjusting for CHF or cirrhosis (p < 0.001). This population PK model enabled assessment of tolvaptan PK with varying degrees of CHF and hepatic cirrhosis with fluid overload and may be used to explore PK-PD relationships with respect to fluid and electrolyte balance.
Collapse
|
27
|
Radin MJ, Yu MJ, Stoedkilde L, Miller RL, Hoffert JD, Frokiaer J, Pisitkun T, Knepper MA. Aquaporin-2 regulation in health and disease. Vet Clin Pathol 2012; 41:455-70. [PMID: 23130944 PMCID: PMC3562700 DOI: 10.1111/j.1939-165x.2012.00488.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Aquaporin-2 (AQP2), the vasopressin-regulated water channel of the renal collecting duct, is dysregulated in numerous disorders of water balance in people and animals, including those associated with polyuria (urinary tract obstruction, hypokalemia, inflammation, and lithium toxicity) and with dilutional hyponatremia (syndrome of inappropriate antidiuresis, congestive heart failure, cirrhosis). Normal regulation of AQP2 by vasopressin involves 2 independent regulatory mechanisms: (1) short-term regulation of AQP2 trafficking to and from the apical plasma membrane, and (2) long-term regulation of the total abundance of the AQP2 protein in the cells. Most disorders of water balance are the result of dysregulation of processes that regulate the total abundance of AQP2 in collecting duct cells. In general, the level of AQP2 in a collecting duct cell is determined by a balance between production via translation of AQP2 mRNA and removal via degradation or secretion into the urine in exosomes. AQP2 abundance increases in response to vasopressin chiefly due to increased translation subsequent to increases in AQP2 mRNA. Vasopressin-mediated regulation of AQP2 gene transcription is poorly understood, although several transcription factor-binding elements in the 5' flanking region of the AQP2 gene have been identified, and candidate transcription factors corresponding to these elements have been discovered in proteomics studies. Here, we review progress in this area and discuss elements of vasopressin signaling in the collecting duct that may impinge on regulation of AQP2 in health and in the context of examples of polyuric diseases.
Collapse
Affiliation(s)
- M. Judith Radin
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH
| | - Ming-Jiun Yu
- Epithelial Systems Biology Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
- Institute of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei, TAIWAN
| | - Lene Stoedkilde
- Epithelial Systems Biology Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
- The Water and Salt Research Center, University of Aarhus, DK-8000 C, Denmark
| | - R. Lance Miller
- Epithelial Systems Biology Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Jason D. Hoffert
- Epithelial Systems Biology Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Jorgen Frokiaer
- The Water and Salt Research Center, University of Aarhus, DK-8000 C, Denmark
| | - Trairak Pisitkun
- Epithelial Systems Biology Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Mark A. Knepper
- Epithelial Systems Biology Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| |
Collapse
|
28
|
Conner AC, Bill RM, Conner MT. An emerging consensus on aquaporin translocation as a regulatory mechanism. Mol Membr Biol 2012; 30:1-12. [DOI: 10.3109/09687688.2012.743194] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
29
|
Cabral PD, Herrera M. Membrane-associated aquaporin-1 facilitates osmotically driven water flux across the basolateral membrane of the thick ascending limb. Am J Physiol Renal Physiol 2012; 303:F621-9. [PMID: 22674028 PMCID: PMC3468494 DOI: 10.1152/ajprenal.00268.2012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Accepted: 06/05/2012] [Indexed: 11/22/2022] Open
Abstract
The thick ascending limb of the loop of Henle (TAL) reabsorbs ∼30% of filtered NaCl but is impermeable to water. The observation that little water traverses the TAL indicates an absence of water channels at the apical membrane. Yet TAL cells swell when peritubular osmolality decreases indicating that water channels must be present in the basolateral side. Consequently, we hypothesized that the water channel aquaporin-1 (AQP1) facilitates water flux across the basolateral membrane of TALs. Western blotting revealed AQP1 expression in microdissected rat and mouse TALs. Double immunofluorescence showed that 95 ± 2% of tubules positive for the TAL-specific marker Tamm-Horsfall protein were also positive for AQP1 (n = 6). RT-PCR was used to demonstrate presence of AQP1 mRNA and the TAL-specific marker NKCC2 in microdissected TALs. Cell surface biotinylation assays showed that 23 ± 3% of the total pool of AQP1 was present at the TAL basolateral membrane (n = 7). To assess the functional importance of AQP1 in the basolateral membrane, we measured the rate of cell swelling initiated by decreasing peritubular osmolality as an indicator of water flux in microdissected TALs. Water flux was decreased by ∼50% in Aqp1 knockout mice compared with wild-types (4.0 ± 0.8 vs. 8.9 ± 1.7 fluorescent U/s, P < 0.02; n = 7). Furthermore, arginine vasopressin increased TAL AQP1 expression by 135 ± 17% (glycosylated) and 41 ± 11% (nonglycosylated; P < 0.01; n =5). We conclude that 1) the TAL expresses AQP1, 2) ∼23% of the total pool of AQP1 is localized to the basolateral membrane, 3) AQP1 mediates a significant portion of basolateral water flux, and 4) AQP1 is upregulated in TALs of rats infused with dDAVP. AQP1 could play an important role in regulation of TAL cell volume during changes in interstitial osmolality, such as during a high-salt diet or water deprivation.
Collapse
Affiliation(s)
- Pablo D Cabral
- Division of Hypertension and Vascular Research, Henry Ford Hospital, Detroit, Michigan, USA
| | | |
Collapse
|
30
|
Vasopressin increases S261 phosphorylation in AQP2-P262L, a mutant in recessive nephrogenic diabetes insipidus. Nephrol Dial Transplant 2012; 27:4389-97. [DOI: 10.1093/ndt/gfs292] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
|
31
|
Genetic predisposition and nongenetic risk factors of thiazolidinedione-related edema in patients with type 2 diabetes. Pharmacogenet Genomics 2012; 21:829-36. [PMID: 21934636 DOI: 10.1097/fpc.0b013e32834bfff1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE This study aimed to analyze the association of thiazolidinedione (TZD)-related edema with genetic and clinical variables and develop a simple points system to predict the risk of developing TZD-related edema. METHODS Fifty-eight (21.6%) of 268 individuals who received TZD for type 2 diabetes developed peripheral edema. Twenty-eight tag single nucleotide polymorphisms (SNPs) from candidate genes involved in sodium and water reabsorption were genotyped. Cox regression and logistic regression models were used to analyze the associations of different genotypes and weighted genotypic scores with TZD-related edema risk. RESULTS Individuals with edema were older, predominantly female, and had greater weight gain. The AQP2 rs296766 T allele was associated with TZD-related edema [allelic P=0.0059; odds ratio (OR), 2.89; 95% confidence interval (CI), 1.61-5.17]. The SLC12A rs12904216 G allele had borderline significance (allelic P=0.049), which disappeared after correction for multiple testing. Patients with two SNP-based (AQP2 rs296766 and SLC12A1 rs12904216), who weighted genotypic scores within the top quartile, had a higher risk of developing TZD-related edema (OR, 16.45; 95% CI, 3.05-88.76). Combining the weighted genetic scores of two SNPs or all SNPs with age and sex information significantly improved the predictive power for TZD-related edema. We also developed a simple risk factor-based points system to predict an individual's risk of developing TZD-related edema. CONCLUSION A clinically applicable prediction model including age, sex, and genetic information from AQP2 rs296766 and/or SLC12A rs12904216 SNPs can be developed to estimate the risk of TZD-related edema in type 2 diabetes patients.
Collapse
|
32
|
Bohn AB, Nørregaard R, Stødkilde L, Wang Y, Bertelsen LB, Fenton RA, Matchkov VV, Bouzinova EV, Horsman MR, Frøkiær J, Stødkilde-Jørgensen H. Treatment with the vascular disrupting agent combretastatin is associated with impaired AQP2 trafficking and increased urine output. Am J Physiol Regul Integr Comp Physiol 2012; 303:R186-98. [PMID: 22621967 DOI: 10.1152/ajpregu.00572.2011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Combretastatin A-4 disodium phosphate (CA4P) is a vascular disrupting agent known to mediate its effects primarily on tumor blood vessels. CA4P has previously been shown to induce a significant increase in mean arterial blood pressure and in hemoglobin concentration in mice. In the present study, we examined whether this is associated with a general leakage of water into certain tissues or with changes in renal water handling. Munich-Wistar rats received either CA4P (30 mg/kg body wt) or saline intraperitoneally as a bolus injection. One hour later, hemoglobin concentration and mean blood pressure increased significantly. MRI showed no significant changes in tissue water content following CA4P administration. However, urine output and salt excretion increased 1 h after CA4P treatment, without changes in urinary and medullary osmolality. Aquaporin 2 (AQP2) mRNA levels in kidney inner medulla did not change 1 h after CA4P treatment, but semiquantitative confocal laser-scanning microscopy analysis demonstrated a decrease in phosphorylated AQP2 (pS256-AQP2) apical distribution within the collecting ducts of CA4P-treated rats compared with the characteristic apical localization in control rats. Furthermore, we demonstrated that CA4P cause disruption of microtubules and a weaker apical labeling of pS256-AQP2 in collecting duct principal cells within 1 h. In conclusion, our data indicate that water escapes from the vascular system after CA4P treatment, and it may take place primarily through a renal mechanism. The CA4P-mediated increase in urine output seems to be a local effect in the collecting ducts due to reduced AQP2 trafficking to the apical plasma membrane.
Collapse
Affiliation(s)
- Anja B Bohn
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Nørrebrogade, Denmark.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Velagapudi C, Nilsson RP, Lee MJ, Burns HS, Ricono JM, Arar M, Barnes VL, Abboud HE, Barnes JL. Reciprocal induction of simple organogenesis by mouse kidney progenitor cells in three-dimensional co-culture. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 180:819-30. [PMID: 22138298 DOI: 10.1016/j.ajpath.2011.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 10/12/2011] [Accepted: 11/01/2011] [Indexed: 10/14/2022]
Abstract
Kidney development is regulated by a coordinated reciprocal induction of metanephric mesenchymal (MM) and ureteric bud (UB) cells. Here, established MM and UB progenitor cell lines were recombined in three-dimensional Matrigel implants in SCID mice. Differentiation potential was examined for changes in phenotype, organization, and the presence of specialized proteins using immunofluorescence and bright-field and electron microscopy. Both cell types, when grown alone, did not develop into specialized structures. When combined, the cells organized into simple organoid structures of polarized epithelia with lumens surrounded by capillary-like structures. Tracker experiments indicated the UB cells formed the tubuloid structures, and the MM cells were the source of the capillary-like cells. The epithelial cells stained positive for pancytokeratin, the junctional complex protein ZO-1, collagen type IV, as well as UB and collecting duct markers, rearranged during transfection (RET), Dolichos biflorus lectin, EndoA cytokeratin, and aquaporin 2. The surrounding cells expressed α-smooth muscle actin, vimentin, platelet endothelial cell adhesion molecule 1 (PECAM), and aquaporin 1, a marker of vasculogenesis. The epithelium exhibited apical vacuoles, microvilli, junctional complexes, and linear basement membranes. Capillary-like structures showed endothelial features with occasional pericytes. UB cell epithelialization was augmented in the presence of MM cell-derived conditioned medium, glial-derived neurotrophic factor (GDNF), hepatocyte growth factor (HGF), or fibronectin. MM cells grown in the presence of UB-derived conditioned medium failed to undergo differentiation. However, UB cell-derived conditioned medium induced MM cell migration. These studies indicate that tubulogenesis and vasculogenesis can be partially recapitulated by recombining individual MM and UB cell lineages, providing a new model system to study organogenesis ex vivo.
Collapse
Affiliation(s)
- Chakradhar Velagapudi
- Division of Nephrology, Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229-3900, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Renal and vascular mechanisms of thiazolidinedione-induced fluid retention. PPAR Res 2011; 2008:943614. [PMID: 18784848 PMCID: PMC2531205 DOI: 10.1155/2008/943614] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Accepted: 06/04/2008] [Indexed: 11/18/2022] Open
Abstract
Thiazolidinediones (TZDs) are peroxisome proliferator-activated receptor subtype gamma (PPARgamma) activators that are clinically used as an insulin sensitizer for glycemic control in patients with type 2 diabetes. Additionally, TZDs exhibit novel anti-inflammatory, antioxidant, and antiproliferative properties, indicating therapeutic potential for a wide variety of diseases associated with diabetes and other conditions. The clinical applications of TZDs are limited by the common major side effect of fluid retention. A better understanding of the molecular mechanism of TZD-induced fluid retention is essential for the development of novel therapies with improved safety profiles. An important breakthrough in the field is the finding that the renal collecting duct is a major site for increased fluid reabsorption in response to rosiglitazone or pioglitazone. New evidence also indicates that increased vascular permeability in adipose tissues may contribute to edema formation and body weight gain. Future research should therefore be directed at achieving a better understanding of the detailed mechanisms of TZD-induced increases in renal sodium transport and in vascular permeability.
Collapse
|
35
|
Altered expression of renal aquaporins and α-adducin polymorphisms may contribute to the establishment of salt-sensitive hypertension. Am J Hypertens 2011; 24:822-8. [PMID: 21451595 DOI: 10.1038/ajh.2011.47] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Sodium-sensitive hypertension is caused by renal tubular dysfunction, leading to increased retention of sodium and water. Previous findings have suggested that single-nucleotide polymorphisms of the cytoskeletal protein, α-adducin, are associated with increased membrane expression of the Na/K pump and abnormal renal sodium transport in Milan hypertensive strain (MHS) rats and in humans. However, the possible contribution of renal aquaporins (AQPs) to water retention remains undefined in MHS rats. METHODS Kidneys from MHS rats were analyzed and compared with those from age-matched Milan normotensive strain (MNS) animals by quantitative-PCR, immunoblotting, and immunoperoxidase. Endocytosis assay was performed on renal cells stably expressing AQP4 and co-transfected either with wild-type normotensive (NT) or with mutated hypertensive (HT) α-adducin. RESULTS Semiquantitative immunoblotting revealed that AQP1 abundance was significantly decreased only in HT MHS whereas AQP2 was reduced in both young pre-HT and adult-HT animals. On the other hand, AQP4 was dramatically upregulated in MHS regardless of the age. These results were confirmed by immunoperoxidase microscopy. Endocytosis assays clearly showed that the expression of mutated adducin strongly reduced the rate of constitutive AQP4 endocytosis, thereby increasing its abundance at the plasma membrane. CONCLUSIONS We provide here the first evidence that AQP1, AQP2, and AQP4 are dysregulated in the kidneys of MHS animals. In particular, we provide evidence that α-adducin mutations may be responsible for AQP4 upregulation. The downregulation of AQP1 and AQP2 and the upregulation of AQP4 may be relevant for the onset and maintenance of salt-sensitive hypertension.
Collapse
|
36
|
Fuente Mora C, Ranghini E, Bruno S, Bussolati B, Camussi G, Wilm B, Edgar D, Kenny SE, Murray P. Differentiation of podocyte and proximal tubule-like cells from a mouse kidney-derived stem cell line. Stem Cells Dev 2011; 21:296-307. [PMID: 21510739 DOI: 10.1089/scd.2010.0470] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In this study we have shown that the papilla of the mouse kidney contains a population of Pax2+ cells that are detectable from the early postnatal period through to adulthood. Lineage analysis suggests that some of these Pax2+ cells are derived from the metanephric mesenchyme, a population of progenitor cells that gives rise to the nephrons during kidney organogenesis. Here we describe a method for isolating and culturing the Pax2+ population, and demonstrate that some cells within this population are multipotent stem cells, as they are clonogenic and appear to undergo unlimited self-renewal. Further, under appropriate culture conditions, these stem cells can differentiate to generate renal cell types, such as podocyte- and proximal tubule-like cells, and are also able to generate nonrenal cell types, such as adipocytes and osteocytes. The availability of a kidney-derived multipotent stem cell line with the potential to generate podocytes and proximal tubule cells in culture will expedite progress in understanding the biology of these important renal cell types, and will be a useful tool in toxicological studies and drug discovery.
Collapse
Affiliation(s)
- Cristina Fuente Mora
- Faculty of Health and Life Sciences, The University of Liverpool, Liverpool, United Kingdom
| | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Li W, Zhang Y, Bouley R, Chen Y, Matsuzaki T, Nunes P, Hasler U, Brown D, Lu HAJ. Simvastatin enhances aquaporin-2 surface expression and urinary concentration in vasopressin-deficient Brattleboro rats through modulation of Rho GTPase. Am J Physiol Renal Physiol 2011; 301:F309-18. [PMID: 21511701 DOI: 10.1152/ajprenal.00001.2011] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Statins are 3-hydroxyl-3-methyglutaryl-CoA reductase inhibitors that are commonly used to inhibit cholesterol biosynthesis. Emerging data have suggested that they also have "pleotropic effects," including modulating actin cytoskeleton reorganization. Here, we report an effect of simvastatin on the trafficking of aquaporin-2 (AQP2). Specifically, simvastatin induced the membrane accumulation of AQP2 in cell cultures and kidneys in situ. The effect of simvastatin was independent of protein kinase A activation and phosphorylation at AQP2-Ser(256), a critical event involved in vasopressin (VP)-regulated AQP2 trafficking. Further investigation showed that simvastatin inhibited endocytosis in parallel with downregulation of RhoA activity. Overexpression of active RhoA attenuated simvastatin's effect, suggesting the involvement of this small GTPase in simvastatin-mediated AQP2 trafficking. Finally, the effect of simvastatin on urinary concentration was investigated in VP-deficient Brattleboro rats. Simvastatin acutely (3-6 h) increased urinary concentration and decreased urine output in these animals. In summary, simvastatin regulates AQP2 trafficking in vitro and urinary concentration in vivo via events involving downregulation of Rho GTPase activity and inhibition of endocytosis. Our study provides an alternative mechanism to regulate AQP2 trafficking, bypassing the VP-vasopressin receptor signaling pathway.
Collapse
Affiliation(s)
- Wei Li
- Center for Systems Biology, Program in Membrane Biology, Division of Nephrology, Dept. of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Abstract
The non-peptide vasopressin antagonists (VPA), called vaptans, were developed in the 1990s to antagonize both the pressor and antidiuretic effects of vasopressin. There are three subtypes of VPA receptors: V1a, V1b and V2. V1a receptors are widely distributed in the body, mainly the blood vessels and myocardium. The V1b receptors are located mainly in the anterior pituitary gland and play a role in ACTH release. V2 receptors are located in the collecting tubular renal cells. Both V1a and V1b receptors act through the intracellular phosphoinositol signalling pathway, Ca(++) being the second messenger. V2 receptors work through AMPc generation, which promotes aquaporin 2 (AQP2) trafficking and allows water to enter the cell. The vaptans act competitively at the AVP receptor. The most important are mozavaptan, lixivaptan, satavaptan and tolvaptan, all of which are selective V2 antagonists and are administered through the oral route. In contrast, conivaptan is a dual V1 and V2 antagonist administered through the endovenous route. The main characteristics of vaptans are their effect on free water elimination without affecting electrolyte excretion. There are several studies on the effects of these drugs in hypervolemic hyponatremia (heart failure, hepatic cirrhosis) as well as in normovolemic hyponatremia (inappropriate secretion of ADH [SIADH]). Current studies show that the vaptans are effective and well tolerated, although knowledge of these drugs remains limited. There are no studies of the use of vaptans in severe hyponatremia. Osmotic demyelination syndrome due to excessively rapid correction of hyponatremia has not been described.
Collapse
Affiliation(s)
- Carles Villabona
- Servicio de Endocrinología y Nutrición, Hospital Universitario de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain
| |
Collapse
|
39
|
Zhang L, Li J, Jiang Z, Sun L, Mei X, Yong B, Zhang L. Inhibition of aquaporin-1 expression by RNAi protects against aristolochic acid I-induced apoptosis in human proximal tubular epithelial (HK-2) cells. Biochem Biophys Res Commun 2011; 405:68-73. [DOI: 10.1016/j.bbrc.2010.12.128] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Accepted: 12/29/2010] [Indexed: 11/15/2022]
|
40
|
Fesenko I, Franklin D, Garnett P, Bass P, Campbell S, Hardyman M, Wilson D, Hanley N, Collins J. Stem cell marker TRA-1-60 is expressed in foetal and adult kidney and upregulated in tubulo-interstitial disease. Histochem Cell Biol 2010; 134:355-69. [PMID: 20853169 DOI: 10.1007/s00418-010-0741-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2010] [Indexed: 10/19/2022]
Abstract
The kidney has an intrinsic ability to repair itself when injured. Epithelial cells of distal tubules may participate in regeneration. Stem cell marker, TRA-1-60 is linked to pluripotency in human embryonic stem cells and is lost upon differentiation. TRA-1-60 expression was mapped and quantified in serial sections of human foetal, adult and diseased kidneys. In 8- to 10-week human foetal kidney, the epitope was abundantly expressed on ureteric bud and structures derived therefrom including collecting duct epithelium. In adult kidney inner medulla/papilla, comparisons with reactivity to epithelial membrane antigen, aquaporin-2 and Tamm-Horsfall protein, confirmed extensive expression of TRA-1-60 in cells lining collecting ducts and thin limb of the loop of Henle, which may be significant since the papillae were proposed to harbour slow cycling cells involved in kidney homeostasis and repair. In the outer medulla and cortex there was rare, sporadic expression in tubular cells of the collecting ducts and nephron, with positive cells confined to the thin limb and thick ascending limb and distal convoluted tubules. Remarkably, in cortex displaying tubulo-interstitial injury, there was a dramatic increase in number of TRA-1-60 expressing individual cells and in small groups of cells in distal tubules. Dual staining showed that TRA-1-60 positive cells co-expressed Pax-2 and Ki-67, markers of tubular regeneration. Given the localization in foetal kidney and the distribution patterns in adults, it is tempting to speculate that TRA-1-60 may identify a population of cells contributing to repair of distal tubules in adult kidney.
Collapse
Affiliation(s)
- Irina Fesenko
- Infection, Inflammation and Immunity Division, School of Medicine, University of Southampton, Southampton, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Marino GI, Castro-Parodi M, Dietrich V, Damiano AE. High levels of human chorionic gonadotropin (hCG) correlate with increased aquaporin-9 (AQP9) expression in explants from human preeclamptic placenta. Reprod Sci 2010; 17:444-53. [PMID: 20220109 DOI: 10.1177/1933719110361385] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Trophoblastic abnormalities have a central role in the pathophysiology of preeclampsia, and some placental hormones, such as human chorionic gonadotropin (hCG), could affect the placental function. Here, we hypothesized that the elevated serum levels of hCG may be involved in the increased aquaporin-9 (AQP9) protein expression in preeclamptic placentas via adenosine 3('),5(')-cyclic phosphate (cAMP) pathways. Normal placental explants were cultured with different concentrations of recombinant hCG or 8-Br-cAMP, a potent analogue of cAMP. We evaluated AQP9 protein expression and localization. After both treatments, we localized AQP9 in the apical membrane of syncytiotrophoblast and in the cytoplasm. We also observed a concentration-dependent effect on AQP9 protein expression. In addition, water uptake increased 1.6-fold in explants treated with hCG. Our results suggest that hCG may increase AQP9 protein expression and functionality via cAMP pathways. Although, in preeclamptic placentas high levels of hCG may upregulate AQP9 protein expression, AQP9 functionality was reduced possibly by other factors.
Collapse
Affiliation(s)
- Gabriela I Marino
- Laboratorio de Canales iónicos-Neurofisiología, Instituto de Investigaciones Médicas A. Lanari, Universidad de Buenos Aires-CONICET, Argentina
| | | | | | | |
Collapse
|
42
|
Buemi M, Bolignano D, Coppolino G, Di Pasquale G, Cosentini V, Campo S, Barillà A, Aloisi C. Aquaporin-2 (AQP2) Urinary Excretion and Assumption of Water with Different Mineral Content in Healthy Subjects. Ren Fail 2009; 29:567-72. [PMID: 17654319 DOI: 10.1080/08860220701392082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
The aquaporin-2 (AQP2) plays a key role in AVP-induced absorption of water, and its urinary excretion is related to its function. We aimed to test if the assumption of water with different mineral content can modify the expression of AQP2, leading to a change in AQP2 urinary concentration, in 20 healthy young subjects. Each subject received an oral water load (LM or HM) of 250 mL/hour for four hours, and several variables were measured. Plasmatic osmolality after water assumption was significantly reduced with no differences after the low (LM) or the high mineral (HM) water load. Urinary osmolality and plasmatic vasopressin concentration were significantly reduced after an assumption of both kinds of water. However, serum vasopressin was lower after HM water assumption than after LM. AQP2 urinary excretion was significantly reduced after water assumption with respect to the basal level and it was lower after LM than after HM water assumption. The different mineral content of water was investigated as a factor contributing to the development of hypertension. Considering that AQP2 can play a role in pathogenesis of hypertension, our demonstration that AVP-mediated AQP2 urinary excretion is strictly influenced by the consumption of water with different mineral content suggests a new, interesting field of investigation related to the link between blood pressure alterations and nutritional habits.
Collapse
Affiliation(s)
- Michele Buemi
- Department of Internal Medicine, University of Messina, Messina, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
43
|
CFTR May Modulate AQP9 Functionality in Preeclamptic Placentas. Placenta 2009; 30:642-8. [DOI: 10.1016/j.placenta.2009.04.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 03/27/2009] [Accepted: 04/29/2009] [Indexed: 11/23/2022]
|
44
|
Kumar M, Grzelakowski M, Zilles J, Clark M, Meier W. Highly permeable polymeric membranes based on the incorporation of the functional water channel protein Aquaporin Z. Proc Natl Acad Sci U S A 2007; 104:20719-24. [PMID: 18077364 PMCID: PMC2410068 DOI: 10.1073/pnas.0708762104] [Citation(s) in RCA: 416] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2007] [Indexed: 11/18/2022] Open
Abstract
The permeability and solute transport characteristics of amphiphilic triblock-polymer vesicles containing the bacterial water-channel protein Aquaporin Z (AqpZ) were investigated. The vesicles were made of a block copolymer with symmetric poly-(2-methyloxazoline)-poly-(dimethylsiloxane)-poly-(2-methyloxazoline) (PMOXA(15)-PDMS(110)-PMOXA(15)) repeat units. Light-scattering measurements on pure polymer vesicles subject to an outwardly directed salt gradient in a stopped-flow apparatus indicated that the polymer vesicles were highly impermeable. However, a large enhancement in water productivity (permeability per unit driving force) of up to approximately 800 times that of pure polymer was observed when AqpZ was incorporated. The activation energy (E(a)) of water transport for the protein-polymer vesicles (3.4 kcal/mol) corresponded to that reported for water-channel-mediated water transport in lipid membranes. The solute reflection coefficients of glucose, glycerol, salt, and urea were also calculated, and indicated that these solutes are completely rejected. The productivity of AqpZ-incorporated polymer membranes was at least an order of magnitude larger than values for existing salt-rejecting polymeric membranes. The approach followed here may lead to more productive and sustainable water treatment membranes, whereas the variable levels of permeability obtained with different concentrations of AqpZ may provide a key property for drug delivery applications.
Collapse
Affiliation(s)
- Manish Kumar
- *Department of Civil and Environmental Engineering, University of Illinois at Urbana–Champaign, 205 North Mathews Avenue, Urbana, IL 61801; and
| | - Mariusz Grzelakowski
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
| | - Julie Zilles
- *Department of Civil and Environmental Engineering, University of Illinois at Urbana–Champaign, 205 North Mathews Avenue, Urbana, IL 61801; and
| | - Mark Clark
- *Department of Civil and Environmental Engineering, University of Illinois at Urbana–Champaign, 205 North Mathews Avenue, Urbana, IL 61801; and
| | - Wolfgang Meier
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
| |
Collapse
|
45
|
Essential role of cleavage of Polycystin-1 at G protein-coupled receptor proteolytic site for kidney tubular structure. Proc Natl Acad Sci U S A 2007; 104:18688-93. [PMID: 18003909 DOI: 10.1073/pnas.0708217104] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Polycystin-1 (PC1) has an essential function in renal tubular morphogenesis and disruption of its function causes cystogenesis in human autosomal dominant polycystic kidney disease. We have previously shown that recombinant human PC1 is cis-autoproteolytically cleaved at the G protein-coupled receptor proteolytic site domain. To investigate the role of cleavage in vivo, we generated by gene targeting a Pkd1 knockin mouse (Pkd1(V/V)) that expresses noncleavable PC1. The Pkd1(V/V) mice show a hypomorphic phenotype, characterized by a delayed onset and distal nephron segment involvement of cystogenesis at postnatal maturation stage. We show that PC1 is ubiquitously and incompletely cleaved in wild-type mice, so that uncleaved and cleaved PC1 molecules coexist. Our study establishes a critical but restricted role of cleavage for PC1 function and suggests a differential function of the two types of PC1 molecules in vivo.
Collapse
|
46
|
Lu HAJ, Sun TX, Matsuzaki T, Yi XH, Eswara J, Bouley R, McKee M, Brown D. Heat shock protein 70 interacts with aquaporin-2 and regulates its trafficking. J Biol Chem 2007; 282:28721-28732. [PMID: 17636261 DOI: 10.1074/jbc.m611101200] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The trafficking of aquaporin-2 (AQP2) involves multiple complex pathways, including regulated, cAMP-, and cGMP-mediated pathways, as well as a constitutive recycling pathway. Although several accessory proteins have been indirectly implicated in AQP2 recycling, the direct protein-protein interactions that regulate this process remain largely unknown. Using yeast two-hybrid screening of a human kidney cDNA library, we have identified the 70-kDa heat shock proteins as AQP2-interacting proteins. Interaction was confirmed by mass spectrometry of proteins pulled down from rat kidney papilla extract using a GST-AQP2 C-terminal fusion protein (GST-A2C) as a bait, by co-immunoprecipitation (IP) assays, and by direct binding assays using purified hsc70 and the GST-A2C. The direct interaction of AQP2 with hsc70 is partially inhibited by ATP, and the Ser-256 residue in the AQP2 C terminus is important for this direct interaction. Vasopressin stimulation in cells enhances the interaction of hsc70 with AQP2 in IP assays, and vasopressin stimulation in vivo induces an increased co-localization of hsc70 and AQP2 on the apical membrane of principal cells in rat kidney collecting ducts. Functional knockdown of hsc70 activity in AQP2 expressing cells results in membrane accumulation of AQP2 and reduced endocytosis of rhodamine-transferrin. Our data also show that AQP2 interacts with hsp70 in multiple in vitro binding assays. Finally, in addition to hsc70 and hsp70, AQP2 interacts with several other key components of the endocytotic machinery in co-IP assays, including clathrin, dynamin, and AP2. To summarize, we have identified the 70-kDa heat shock proteins as a AQP2 interactors and have shown for hsc70 that this interaction is involved in AQP2 trafficking.
Collapse
Affiliation(s)
- Hua A J Lu
- Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114.
| | - Tian-Xiao Sun
- Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Toshiyuki Matsuzaki
- Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Xian-Hua Yi
- Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Jairam Eswara
- Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Richard Bouley
- Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Mary McKee
- Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - Dennis Brown
- Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114.
| |
Collapse
|
47
|
Floyd RV, Mason SL, Proudman CJ, German AJ, Marples D, Mobasheri A. Expression and nephron segment-specific distribution of major renal aquaporins (AQP1-4) in Equus caballus, the domestic horse. Am J Physiol Regul Integr Comp Physiol 2007; 293:R492-503. [PMID: 17442782 DOI: 10.1152/ajpregu.00689.2005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Aquaporins (AQPs) play fundamental roles in water and osmolyte homeostasis by facilitating water and small solute movement across plasma membranes of epithelial, endothelial, and other tissues. AQP proteins are abundantly expressed in the mammalian kidney, where they have been shown to play essential roles in fluid balance and urine concentration. Thus far, the majority of studies on renal AQPs have been carried out in laboratory rodents and sheep; no data have been published on the expression of AQPs in kidneys of equines or other large mammals. The aim of this comparative study was to determine the expression and nephron segment localization of AQP1-4 in Equus caballus by immunoblotting and immunohistochemistry with custom-designed rabbit polyclonal antisera. AQP1 was found in apical and basolateral membranes of the proximal convoluted tubules and thin descending limbs of the loop of Henle. AQP2 expression was specifically detected in apical membranes of cortical, medullary, and papillary collecting ducts. AQP3 was expressed in basolateral membranes of cortical, medullary, and papillary collecting ducts. Immunohistochemistry also confirmed AQP4 expression in basolateral membranes of cells lining the distal convoluted and connecting tubules. Western blots revealed high expression of AQP1-4 in the equine kidney. These observations confirm that AQPs are expressed in the equine kidney and are found in similar nephron locations to mouse, rat, and human kidney. Equine renal AQP proteins are likely to be involved in acute and chronic regulation of body fluid composition and may be implicated in water balance disorders brought about by colic and endotoxemia.
Collapse
Affiliation(s)
- R V Floyd
- Department of Physiology, Faculty of Veterinary Science, University of Liverpool, Liverpool, UK
| | | | | | | | | | | |
Collapse
|
48
|
Abstract
Water arrives in the mammalian gestation from the maternal circulation across the placenta. It then circulates between the fetal water compartments, including the fetal body compartments, the placenta and the amniotic fluid. Amniotic fluid is created by the flow of fluid from the fetal lung and bladder. A major pathway for amniotic fluid resorption is fetal swallowing; however, in many cases the amounts of fluid produced and absorbed do not balance. A second resorption pathway, the intramembranous pathway (across the amnion to the fetal circulation), has been proposed to explain the maintenance of normal amniotic fluid volume. Amniotic fluid volume is thus a function both of the amount of water transferred to the gestation across the placental membrane, and the flux of water across the amnion. Water flux across biologic membranes may be driven by osmotic or hydrostatic forces; existing data suggest that intramembranous flow in humans is driven by the osmotic difference between the amniotic fluid and the fetal serum. The driving force for placental flow is more controversial, and both forces may be in effect. The mechanism(s) responsible for regulating water flow to and from the amniotic fluid is unknown. In other parts of the body, notably the kidney, water flux is regulated by the expression of aquaporin water channels on the cell membrane. We hypothesize that aquaporins have a role in regulating water flux across both the amnion and the placenta, and present evidence in support of this theory. Current knowledge of gestational water flow is sufficient to allow prediction of fetal outcome when water flow is abnormal, as in twin-twin transfusion syndrome. Further insight into these mechanisms may allow novel treatments for amniotic fluid volume abnormalities with resultant improvement in clinical outcome.
Collapse
Affiliation(s)
- M H Beall
- Department of Obstetrics and Gynecology, Harbor-UCLA Medical Center, 1000 W. Carson Street, Box 3, Torrance, CA 90502, USA.
| | | | | | | |
Collapse
|
49
|
Nasrallah R, Xiong H, Hébert RL. Renal prostaglandin E2 receptor (EP) expression profile is altered in streptozotocin and B6-Ins2Akita type I diabetic mice. Am J Physiol Renal Physiol 2006; 292:F278-84. [PMID: 16954344 DOI: 10.1152/ajprenal.00089.2006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The homeostatic function of prostaglandin E(2) (PGE(2)) is dependent on a balance of EP receptor-mediated events. A disruption in this balance may contribute to the progression of renal injury. Although PGE(2) excretion is elevated in diabetes, the expression of specific EP receptor subtypes has not been studied in the diabetic kidney. Therefore, the purpose of this study was to characterize the expression profile of four EP receptor subtypes (EP(1-4)) in 16-wk streptozotocin (STZ) and B6-Ins2(Akita) type I diabetic mice. In diabetic mice, the ratio of kidney weight to body weight was increased twofold compared with controls, blood glucose was elevated, but urine albumin was only increased in B6-Ins2(Akita) mice. The excretion of PGE(2) and its metabolite was augmented two- to fourfold as determined by enzyme immunoassay. Accordingly, renal cyclooxygenases were also increased in diabetic mice, with isoform-specific and regional differences in each model. Finally, there was altered EP(1-4) receptor expression in diabetic kidneys, with significant differences between STZ and B6-Ins2(Akita) mice (fold-control). In STZ mice, cortical EP(1) increased by 1.6, EP(3) increased by 2.3, and EP(4) decreased by 0.63; yet in B6-Ins2(Akita) mice, cortical EP(1) increased by 2.4, but there was a general decrease in the remaining subtypes. Similarly, in the STZ medulla EP(3) increased by 3.6, but both EP(1) and EP(3) increased by 5.5 and 1.95, respectively, in B6-Ins2(Akita) mice. Therefore, knowing the pattern of change in relative EP receptor expression in the kidney could be useful in identifying specific EP targets for the prevention of various components of diabetic kidney disease.
Collapse
Affiliation(s)
- Rania Nasrallah
- Department of Cellular and Molecular Medicine, Kidney Research Centre, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | | | | |
Collapse
|
50
|
Tiwari S, Packer RK, Hu X, Sugimura Y, Verbalis JG, Ecelbarger CA. Increased renal α-ENaC and NCC abundance and elevated blood pressure are independent of hyperaldosteronism in vasopressin escape. Am J Physiol Renal Physiol 2006; 291:F49-57. [PMID: 16449357 DOI: 10.1152/ajprenal.00390.2005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previously, we demonstrated that rats undergoing vasopressin escape had increased mean arterial blood pressure (MAP), plasma and urine aldosterone, and increased renal protein abundance of the α-subunit of the epithelial sodium channel (ENaC), the thiazide-sensitive Na-Cl cotransporter (NCC), and the 70-kDa band of γ-ENaC (Song J, Hu X, Khan O, Tian Y, Verbalis JG, and Ecelbarger CA. Am J Physiol Renal Physiol 287: F1076–F1083, 2004; Ecelbarger CA, Knepper MA, and Verbalis JG. J Am Soc Nephrol 12: 207–217, 2001). Here, we determine whether changes in these renal proteins and MAP require elevated aldosterone levels. We performed adrenalectomies (ADX) or sham surgeries on male Sprague-Dawley rats. Corticosterone and aldosterone were replaced to clamp these hormone levels. MAP was monitored by radiotelemetry. Rats were infused with 1-deamino-[8-d-arginine]-vasopressin (dDAVP) via osmotic minipumps (5 ng/h). At day 3 of dDAVP infusion, seven rats in each group were offered a liquid diet [water load (WL)] or continued on a solid diet (SD). Plasma aldosterone and corticosterone and urine aldosterone were increased by WL in sham rats. ADX-WL rats escaped, as assessed by early natriuresis followed by diuresis; however, urine volume and natriuresis were somewhat blunted. WL did not reduce the abundance or activity of 11-β-hydroxsteroid dehydrogenase type 2. Furthermore, the previously observed increase in renal aldosterone-sensitive proteins and escape-associated increased MAP persisted in clamped rats. The densitometry of immunoblots for NCC, α- and γ-70 kDa ENaC, respectively, were (% sham-SD): sham-WL, 159, 278, 233; ADX-SD, 69, 212, 171; ADX-WL, 116, 302, 161. However, clamping corticosteroids blunted the rise at least for NCC and γ-ENaC (70 kDa). Overall, the increase in aldosterone observed in vasopressin escape is not necessary for the increased expression of NCC, α- or γ-ENaC or increased MAP associated with “escape.”
Collapse
Affiliation(s)
- Swasti Tiwari
- Department of Medicine, and Center for Sex Differences, Bldg D, Rm 232, Georgetown University, 4000 Reservoir Rd NW, Washington, DC 20057-1412, USA
| | | | | | | | | | | |
Collapse
|