151
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Wnt/β-catenin links oxidative stress to podocyte injury and proteinuria. Kidney Int 2019; 95:830-845. [PMID: 30770219 DOI: 10.1016/j.kint.2018.10.032] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 10/03/2018] [Accepted: 10/24/2018] [Indexed: 02/07/2023]
Abstract
Podocyte injury is the major cause of proteinuria in primary glomerular diseases. Oxidative stress has long been thought to play a role in triggering podocyte damage; however, the underlying mechanism remains poorly understood. Here we show that the Wnt/β-catenin pathway is involved in mediating oxidative stress-induced podocyte dysfunction. Advanced oxidation protein products, a marker and trigger of oxidative stress, were increased in the serum of patients with chronic kidney disease and correlated with impaired glomerular filtration, proteinuria, and circulating level of Wnt1. Both serum from patients with chronic kidney disease and exogenous advanced oxidation protein products induced Wnt1 and Wnt7a expression, activated β-catenin, and reduced expression of podocyte-specific markers in vitro and in vivo. Blockade of Wnt signaling by Klotho or knockdown of β-catenin by shRNA in podocytes abolished β-catenin activation and the upregulation of fibronectin, desmin, matrix metalloproteinase-9, and Snail1 triggered by advanced oxidation protein products. Furthermore, conditional knockout mice with podocyte-specific ablation of β-catenin were protected against podocyte injury and albuminuria after treatment with advanced oxidation protein products. The action of Wnt/β-catenin was dependent on the receptor of advanced glycation end products (RAGE)-mediated NADPH oxidase induction, reactive oxygen species generation, and nuclear factor-κB activation. These studies uncover a novel mechanistic linkage of oxidative stress, Wnt/β-catenin activation, and podocyte dysfunction.
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152
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Affiliation(s)
- Eli Ben-Chetrit
- From the Infectious Diseases Unit (E.B.-C.), the Adult Nephrology Unit (L.S., A.B.), and the Department of Hematology (A.T.), Shaare Zedek Medical Center, Hebrew University-Hadassah School of Medicine, and the Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center (M.K.) - both in Jerusalem
| | - Linda Shavit
- From the Infectious Diseases Unit (E.B.-C.), the Adult Nephrology Unit (L.S., A.B.), and the Department of Hematology (A.T.), Shaare Zedek Medical Center, Hebrew University-Hadassah School of Medicine, and the Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center (M.K.) - both in Jerusalem
| | - Ariella Tvito
- From the Infectious Diseases Unit (E.B.-C.), the Adult Nephrology Unit (L.S., A.B.), and the Department of Hematology (A.T.), Shaare Zedek Medical Center, Hebrew University-Hadassah School of Medicine, and the Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center (M.K.) - both in Jerusalem
| | - Maya Korem
- From the Infectious Diseases Unit (E.B.-C.), the Adult Nephrology Unit (L.S., A.B.), and the Department of Hematology (A.T.), Shaare Zedek Medical Center, Hebrew University-Hadassah School of Medicine, and the Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center (M.K.) - both in Jerusalem
| | - Alon Bnaya
- From the Infectious Diseases Unit (E.B.-C.), the Adult Nephrology Unit (L.S., A.B.), and the Department of Hematology (A.T.), Shaare Zedek Medical Center, Hebrew University-Hadassah School of Medicine, and the Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center (M.K.) - both in Jerusalem
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153
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Hoyer KJR, Dittrich S, Bartram MP, Rinschen MM. Quantification of molecular heterogeneity in kidney tissue by targeted proteomics. J Proteomics 2019. [DOI: 10.1016/j.jprot.2018.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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154
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Kidney Injury by Variants in the COL4A5 Gene Aggravated by Polymorphisms in Slit Diaphragm Genes Causes Focal Segmental Glomerulosclerosis. Int J Mol Sci 2019; 20:ijms20030519. [PMID: 30691124 PMCID: PMC6386959 DOI: 10.3390/ijms20030519] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 01/21/2019] [Accepted: 01/21/2019] [Indexed: 12/21/2022] Open
Abstract
Kidney injury due to focal segmental glomerulosclerosis (FSGS) is the most common primary glomerular disorder causing end-stage renal disease. Homozygous mutations in either glomerular basement membrane or slit diaphragm genes cause early renal failure. Heterozygous carriers develop renal symptoms late, if at all. In contrast to mutations in slit diaphragm genes, hetero- or hemizygous mutations in the X-chromosomal COL4A5 Alport gene have not yet been recognized as a major cause of kidney injury by FSGS. We identified cases of FSGS that were unexpectedly diagnosed: In addition to mutations in the X-chromosomal COL4A5 type IV collagen gene, nephrin and podocin polymorphisms aggravated kidney damage, leading to FSGS with ruptures of the basement membrane in a toddler and early renal failure in heterozygous girls. The results of our case series study suggest a synergistic role for genes encoding basement membrane and slit diaphragm proteins as a cause of kidney injury due to FSGS. Our results demonstrate that the molecular genetics of different players in the glomerular filtration barrier can be used to evaluate causes of kidney injury. Given the high frequency of X-chromosomal carriers of Alport genes, the analysis of genes involved in the organization of podocyte architecture, the glomerular basement membrane, and the slit diaphragm will further improve our understanding of the pathogenesis of FSGS and guide prognosis of and therapy for hereditary glomerular kidney diseases.
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155
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Rinschen MM. Single glomerular proteomics: A novel tool for translational glomerular cell biology. Methods Cell Biol 2019; 154:1-14. [DOI: 10.1016/bs.mcb.2019.03.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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156
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Chen Z, Zhang Y, Zhao X. FAM40A alters the cytoskeleton of podocytes in familial focal and segmental glomerulosclerosis by regulating F-actin and nephrin. Arch Med Sci 2019; 15:165-173. [PMID: 30697267 PMCID: PMC6348344 DOI: 10.5114/aoms.2018.73138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 11/29/2017] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION Familial focal and segmental glomerulosclerosis (FFSGS) was found in a large cohort of patients in our previous study. Under the sponsorship of the National Natural Science Foundation of China, we conducted linkage analysis and full exon sequencing on the genomes of 54 patients diagnosed with FFSGS. The results revealed a FAM40A gene signature in those patients. To determine whether FAM40A was associated with podocyte lesions and whether changes in the podocyte cytoskeleton could affect podocyte function, mouse podocytes (MPs) were used in this study. MATERIAL AND METHODS FAM40A silencing, over-expression and mutant-type over-expression models of renal MPs were established, whereby roles of wild-type FAM40A and mutant FAM40A (c.1562T>C, p521M>T) in regulating the function of the MP cytoskeleton were explored by using cellular immunofluorescence, RT-qPCR and Western blot. RESULTS FAM40A was expressed and localized in MPs and significantly enriched in the nucleus and perinuclear zone. Changes of FAM40A expression altered the morphology of the MPs and their cytoskeletal organization, which was characterized by disordered distribution of F-actin, loss of the foot process architecture and the functional protein of the slit diaphragm nephrin (p < 0.05 or p < 0.01). FAM40A mutation (p521M>T) led to the formation of round and blunt morphology of the MPs and loss of the foot-process structure. In addition, expression of the cytoskeletal protein F-actin was increased and concentrated in FAM40A mutated cells, whereas the expression of nephrin decreased in those cells (p < 0.01). CONCLUSIONS FAM40A played an important role in maintaining the normal morphology and function of MPs by stabilizing the cytoskeleton of MPs. Moreover, mutant FAM40A (p521M>T) was able to alter the morphology and cytoskeleton of the MPs, and to decrease the expression of nephrin, which may be the main factor contributing to FSGS.
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Affiliation(s)
- Zhou Chen
- Division of Nephrology, Shanghai Changzheng Hospital of Second Military Medical University, Kidney Institute of Chinese People’s Liberation Army, Shanghai, China
- Department of Nephrology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Yinghui Zhang
- Division of Nephrology, Shanghai Changzheng Hospital of Second Military Medical University, Kidney Institute of Chinese People’s Liberation Army, Shanghai, China
- Department of Nephrology, Shanghai Yangpu District Central Hospital of Tongji University, Shanghai, China
| | - Xuezhi Zhao
- Division of Nephrology, Shanghai Changzheng Hospital of Second Military Medical University, Kidney Institute of Chinese People’s Liberation Army, Shanghai, China
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157
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Alachkar N, Li J, Matar D, Vujjini V, Alasfar S, Tracy M, Reiser J, Wei C. Monitoring suPAR levels in post-kidney transplant focal segmental glomerulosclerosis treated with therapeutic plasma exchange and rituximab. BMC Nephrol 2018; 19:361. [PMID: 30558559 PMCID: PMC6296111 DOI: 10.1186/s12882-018-1177-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 12/05/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Therapeutic plasma exchange (TPE) is an important therapy for recurrent focal segmental glomerulosclerosis (rFSGS) post kidney transplant. suPAR has been causally implicated in rFSGS, and shown to be a unique biomarker for the occurrence and progression of chronic kidney disease. This study was targeted to evaluate the application of monitoring suPAR in TPE treated rFSGS. METHODS A retrospective (n = 19) and a prospective (n = 15) cohort of post transplant FSGS patients treated with TPE and rituximab were enrolled. We measured serum suPAR levels before and after the combined therapies, and assessed the role of suPAR changes on proteinuria reduction and podocyte β3- integrin activity. RESULTS Treatment with TPE and rituximab resulted in significant decrease in proteinuria and suPAR levels. Among the variables including baseline suPAR, serum creatinine, proteinuria, eGFR, age at diagnosis, age at transplantation, transplantation numbers, time to recurrence, and TPE course numbers, only the reduction in suPAR levels and baseline proteinuria significantly correlated with the changes in proteinuria after treatment, with the former performed better in predicting proteinuria alteration. Additionally, the mean podocyte β3 integrin activity significantly decreased after TPE and rituximab treatment (1.10 ± 0.08) as compared to before treatment (1.34 ± 0.08), p < 0.05. Only the reduction in suPAR predicted the response to therapies with an odds ratio of 1.43, 95% CI (1.02, 2.00), p < 0.05. CONCLUSIONS Serum suPAR levels reduced significantly after TPE and rituximab treatment in post transplant FSGS patients. The reduction in suPAR levels may be utilized to assess the changes in proteinuria and monitor the response to the therapies. Larger, multi-centered prospective studies monitoring serum suPAR levels in TPE managed post transplant FSGS are warranted.
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Affiliation(s)
- Nada Alachkar
- Department of Medicine, Division of Nephrology, The Johns Hopkins University School of Medicine, Baltimore, USA
- Division of Nephrology, Johns Hopkins Hospital, 600 Wolfe St. Carnegie 344B, Baltimore, MD 21287 USA
| | - Jing Li
- Department of Medicine, Rush University Medical Center, 1735 W Harrison ST, Cohn Bldg, 7th Floor, Suite 716, Chicago, IL 60612 USA
| | - Dany Matar
- Department of Medicine, Division of Nephrology, The Johns Hopkins University School of Medicine, Baltimore, USA
| | - Vikas Vujjini
- Department of Medicine, Sinai Hospital, Baltimore, USA
| | - Sami Alasfar
- Department of Medicine, Division of Nephrology, The Johns Hopkins University School of Medicine, Baltimore, USA
| | - Melissa Tracy
- Department of Medicine, Rush University Medical Center, 1735 W Harrison ST, Cohn Bldg, 7th Floor, Suite 716, Chicago, IL 60612 USA
| | - Jochen Reiser
- Department of Medicine, Rush University Medical Center, 1735 W Harrison ST, Cohn Bldg, 7th Floor, Suite 716, Chicago, IL 60612 USA
| | - Changli Wei
- Department of Medicine, Rush University Medical Center, 1735 W Harrison ST, Cohn Bldg, 7th Floor, Suite 716, Chicago, IL 60612 USA
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158
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Mao Y, Zhang M, Liu S, Xu Y, Xue J, Hao C, Lai L. Inflammatory demyelinating neuropathies with focal segmental glomerulosclerosis: Two case reports. Medicine (Baltimore) 2018; 97:e13304. [PMID: 30544390 PMCID: PMC6310532 DOI: 10.1097/md.0000000000013304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
RATIONALE Inflammatory demyelinating neuropathies such as Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy (CIDP), and focal segmental glomerulosclerosis (FSGS) are autoimmune disorders that may have a common pathogenesis. Here, we describe 2 unique cases of FSGS, 1 with GBS and the other with CIPD. We believe that reviewing these multisystemic diseases will help in better understanding of FSGS pathogenesis. PATIENT CONCERNS The 1st patient, a 66-year-old woman, complained of tingling and numbness in the limbs and within 2 days, she developed progressive muscle weakness. The 2nd patient was a 63-year-old man with a complaint of lower-limb edema, lower-limb weakness, and numbness. DIAGNOSIS In the 1st patient, a diagnosis of GBS was confirmed with the nerve conduction velocity test as well as CSF studies. A renal biopsy revealed FSGS. The 2nd patient was diagnosed with CIDP and a subsequent renal biopsy revealed FSGS. INTERVENTIONS Large dose of steroid with calcineurin inhibitor, intravenous immunoglobulin, and supportive treatment. OUTCOMES Neurologic symptoms disappeared, urine protein was maintained at low levels, and no further recurrences were noted in 2 cases. INF2 gene mutation was not found in either case. LESSONS Co-occurrence of inflammatory demyelinating polyneuropathy, GBS, CIDP, and FSGS suggests synergistic cellular and humoral autoimmune mechanisms related to either cross-reactivity within antigenic targets or mimicry epitopes. Further follow-up and intensive study for the pathogenesis are necessary.
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Affiliation(s)
- Yuhe Mao
- Department of Nephrology, Meizhou People's Hospital, Meizhou Hospital Affiliated to Sun Yat-Sen University, Meizhou, Guangdong Province
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Min Zhang
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Shaojun Liu
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yunyu Xu
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Jun Xue
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Chuanming Hao
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Lingyun Lai
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
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159
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Puig-Gay N, Jacobs-Cacha C, Sellarès J, Guirado L, González Roncero F, Jiménez C, Zárraga S, Paul J, Lauzurica R, Alonso Á, Fernández A, Beneyto I, Mazuecos A, Hernández D, Rodriguez-Benot A, Franco A, Jimeno L, Crespo M, Meseguer A, Moreso F, Seron D, Lopez-Hellin J, Cantarell C. Apolipoprotein A-Ib as a biomarker of focal segmental glomerulosclerosis recurrence after kidney transplantation: diagnostic performance and assessment of its prognostic value - a multi-centre cohort study. Transpl Int 2018; 32:313-322. [PMID: 30411406 DOI: 10.1111/tri.13372] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/05/2018] [Accepted: 10/31/2018] [Indexed: 01/02/2023]
Abstract
Recurrence of idiopathic focal segmental glomerulosclerosis (FSGS) is a serious complication after kidney transplantation. FSGS relapse is suspected by a sudden increase in proteinuria but there is not an accurate noninvasive diagnostic tool to confirm this entity or to detect patients at risk. We aimed to validate the diagnostic performance of ApoA-Ib to detect FSGS relapses by measuring urinary ApoA-Ib in a retrospective cohort of 61 kidney transplanted patients (37 FSGS and 24 non-FSGS). In addition, to assess the ApoA-Ib predictive ability, ApoA-Ib was measured periodically in a prospective cohort of 13 idiopathic FSGS patients who were followed during 1 year after transplantation. ApoA-Ib had a sensitivity of 93.3% and a specificity of 90.9% to diagnose FSGS relapses, with a high negative predictive value (95.2%), confirming our previous results. In the prospective cohort, ApoA-Ib predated the recurrence in four of five episodes observed. In the nonrelapsing group (n = 9), ApoA-Ib was negative in 37 of 38 samples. ApoA-Ib has the potential to be a good diagnostic biomarker of FSGS relapses, providing a confident criterion to exclude false positives even in the presence of high proteinuria. It has also the potential to detect patients at risk of relapse, even before transplantation.
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Affiliation(s)
- Natàlia Puig-Gay
- Renal Physiopathology Group-CIBBIM, Hospital Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain
| | - Conxita Jacobs-Cacha
- Renal Physiopathology Group-CIBBIM, Hospital Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain.,Nephrology, Hospital Vall d'Hebron, Barcelona, Spain
| | | | | | | | - Carlos Jiménez
- Nephrology, Hospital Universitario La Paz, Madrid, Spain
| | | | - Javier Paul
- Nephrology, Hospital Miguel Servet, Zaragoza, Spain
| | | | - Ángel Alonso
- Nephrology, Hospital Universitario de A Coruña, A Coruña, Spain
| | | | - Isabel Beneyto
- Nephrology, Hospital Universitari i Politecnic La Fe, Valencia, Spain
| | | | | | | | | | - Luisa Jimeno
- Nephrology, Hospital Virgen de la Arrixaca, Murcia, Spain
| | | | - Anna Meseguer
- Renal Physiopathology Group-CIBBIM, Hospital Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain
| | | | - Daniel Seron
- Nephrology, Hospital Vall d'Hebron, Barcelona, Spain
| | - Joan Lopez-Hellin
- Renal Physiopathology Group-CIBBIM, Hospital Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain
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160
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Mariani LH, Bomback AS, Canetta PA, Flessner MF, Helmuth M, Hladunewich MA, Hogan JJ, Kiryluk K, Nachman PH, Nast CC, Rheault MN, Rizk DV, Trachtman H, Wenderfer SE, Bowers C, Hill-Callahan P, Marasa M, Poulton CJ, Revell A, Vento S, Barisoni L, Cattran D, D'Agati V, Jennette JC, Klein JB, Laurin LP, Twombley K, Falk RJ, Gharavi AG, Gillespie BW, Gipson DS, Greenbaum LA, Holzman LB, Kretzler M, Robinson B, Smoyer WE, Guay-Woodford LM. CureGN Study Rationale, Design, and Methods: Establishing a Large Prospective Observational Study of Glomerular Disease. Am J Kidney Dis 2018; 73:218-229. [PMID: 30420158 PMCID: PMC6348011 DOI: 10.1053/j.ajkd.2018.07.020] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 07/31/2018] [Indexed: 01/01/2023]
Abstract
RATIONALE & OBJECTIVES Glomerular diseases, including minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, and immunoglobulin A (IgA) nephropathy, share clinical presentations, yet result from multiple biological mechanisms. Challenges to identifying underlying mechanisms, biomarkers, and new therapies include the rarity of each diagnosis and slow progression, often requiring decades to measure the effectiveness of interventions to prevent end-stage kidney disease (ESKD) or death. STUDY DESIGN Multicenter prospective cohort study. SETTING & PARTICIPANTS Cure Glomerulonephropathy (CureGN) will enroll 2,400 children and adults with minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, or IgA nephropathy (including IgA vasculitis) and a first diagnostic kidney biopsy within 5 years. Patients with ESKD and those with secondary causes of glomerular disease are excluded. EXPOSURES Clinical data, including medical history, medications, family history, and patient-reported outcomes, are obtained, along with a digital archive of kidney biopsy images and blood and urine specimens at study visits aligned with clinical care 1 to 4 times per year. OUTCOMES Patients are followed up for changes in estimated glomerular filtration rate, disease activity, ESKD, and death and for nonrenal complications of disease and treatment, including infection, malignancy, cardiovascular, and thromboembolic events. ANALYTICAL APPROACH The study design supports multiple longitudinal analyses leveraging the diverse data domains of CureGN and its ancillary program. At 2,400 patients and an average of 2 years' initial follow-up, CureGN has 80% power to detect an HR of 1.4 to 1.9 for proteinuria remission and a mean difference of 2.1 to 3.0mL/min/1.73m2 in estimated glomerular filtration rate per year. LIMITATIONS Current follow-up can only detect large differences in ESKD and death outcomes. CONCLUSIONS Study infrastructure will support a broad range of scientific approaches to identify mechanistically distinct subgroups, identify accurate biomarkers of disease activity and progression, delineate disease-specific treatment targets, and inform future therapeutic trials. CureGN is expected to be among the largest prospective studies of children and adults with glomerular disease, with a broad goal to lessen disease burden and improve outcomes.
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Affiliation(s)
- Laura H Mariani
- Division of Nephrology, Department of Medicine, University of Michigan, Ann Arbor, MI; Arbor Research Collaborative for Health, Ann Arbor, MI.
| | - Andrew S Bomback
- Division of Nephrology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY
| | - Pietro A Canetta
- Division of Nephrology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY
| | - Michael F Flessner
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, MD
| | | | - Michelle A Hladunewich
- Division of Nephrology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Jonathan J Hogan
- Renal-Electrolyte and Hypertension Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Krzysztof Kiryluk
- Division of Nephrology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY
| | - Patrick H Nachman
- Division of Renal Diseases and Hypertension, Department of Medicine, University of Minnesota, Minneapolis, MN
| | - Cynthia C Nast
- Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Michelle N Rheault
- Division of Nephrology, Department of Pediatrics, University of Minnesota Masonic Children's Hospital, Minneapolis, MN
| | - Dana V Rizk
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - Howard Trachtman
- Division of Nephrology, Department of Pediatrics, New York University Langone Medical Center, New York, NY
| | - Scott E Wenderfer
- Renal Section, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
| | - Corinna Bowers
- Center for Clinical and Translational Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH
| | | | - Maddalena Marasa
- Division of Nephrology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY
| | - Caroline J Poulton
- Division of Nephrology and Hypertension, Kidney Center, Department of Medicine, University of North Carolina, Chapel Hill, NC
| | - Adelaide Revell
- Center for Clinical and Translational Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH
| | - Suzanne Vento
- Division of Nephrology, Department of Pediatrics, New York University Langone Medical Center, New York, NY
| | | | - Dan Cattran
- Division of Nephrology, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Vivette D'Agati
- Department of Pathology, Columbia University Medical Center, New York, NY
| | - J Charles Jennette
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC
| | - Jon B Klein
- Department of Medicine, The University of Louisville School of Medicine, and Robley Rex VA Medical Center, Louisville, KY
| | | | - Katherine Twombley
- Pediatric Nephrology, Medical University of South Carolina, Charleston, SC
| | - Ronald J Falk
- Division of Nephrology and Hypertension, Kidney Center, Department of Medicine, University of North Carolina, Chapel Hill, NC
| | - Ali G Gharavi
- Division of Nephrology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY
| | - Brenda W Gillespie
- Department of Biostatistics, School of Public Health, University of Michigan, Ann Arbor, MI
| | - Debbie S Gipson
- Division of Nephrology, Department of Pediatrics, University of Michigan, Ann Arbor, MI
| | | | - Lawrence B Holzman
- Renal-Electrolyte and Hypertension Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Matthias Kretzler
- Division of Nephrology, Department of Medicine, University of Michigan, Ann Arbor, MI
| | - Bruce Robinson
- Division of Nephrology, Department of Medicine, University of Michigan, Ann Arbor, MI; Arbor Research Collaborative for Health, Ann Arbor, MI
| | - William E Smoyer
- Center for Clinical and Translational Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics, The Ohio State University, Columbus, OH
| | - Lisa M Guay-Woodford
- Center for Translational Science, Children's National Health System, Washington, DC
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161
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Liu Y, Wang K, Liang X, Li Y, Zhang Y, Zhang C, Wei H, Luo R, Ge S, Xu G. Complement C3 Produced by Macrophages Promotes Renal Fibrosis via IL-17A Secretion. Front Immunol 2018; 9:2385. [PMID: 30405606 PMCID: PMC6204358 DOI: 10.3389/fimmu.2018.02385] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 09/26/2018] [Indexed: 12/21/2022] Open
Abstract
Complement synthesis in cells of origin is strongly linked to the pathogenesis and progression of renal disease. Multiple studies have examined local C3 synthesis in renal disease and elucidated the contribution of local cellular sources, but the contribution of infiltrating inflammatory cells remains unclear. We investigate the relationships among C3, macrophages and Th17 cells, which are involved in interstitial fibrosis. Here, we report that increased local C3 expression, mainly by monocyte/macrophages, was detected in renal biopsy specimens and was correlated with the severity of renal fibrosis (RF) and indexes of renal function. In mouse models of UUO (unilateral ureteral obstruction), we found that local C3 was constitutively expressed throughout the kidney in the interstitium, from which it was released by F4/80+macrophages. After the depletion of macrophages using clodronate, mice lacking macrophages exhibited reductions in C3 expression and renal tubulointerstitial fibrosis. Blocking C3 expression with a C3 and C3aR inhibitor provided similar protection against renal tubulointerstitial fibrosis. These protective effects were associated with reduced pro-inflammatory cytokines, renal recruitment of inflammatory cells, and the Th17 response. in vitro, recombinant C3a significantly enhanced T cell proliferation and IL-17A expression, which was mediated through phosphorylation of ERK, STAT3, and STAT5 and activation of NF-kB in T cells. More importantly, blockade of C3a by a C3aR inhibitor drastically suppressed IL-17A expression in C3a-stimulated T cells. We propose that local C3 secretion by macrophages leads to IL-17A-mediated inflammatory cell infiltration into the kidney, which further drives fibrogenic responses. Our findings suggest that inhibition of the C3a/C3aR pathway is a novel therapeutic approach for obstructive nephropathy.
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Affiliation(s)
- Yanyan Liu
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Kun Wang
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xinjun Liang
- Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yueqiang Li
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ying Zhang
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chunxiu Zhang
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Haotian Wei
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ran Luo
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shuwang Ge
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Gang Xu
- Division of Internal Medicine, Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Husain S, Ginawi I, Bashir AI, Kfoury H, Al Johani TE, Hagar H, Raddaoui L, Al Ghonaim M, Alsuwaida A. Focal and segmental glomerulosclerosis in murine models: a histological and ultrastructural characterization with immunohistochemistry correlation of glomerular CD44 and WT1 expression. Ultrastruct Pathol 2018; 42:430-439. [PMID: 30285525 DOI: 10.1080/01913123.2018.1501125] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AIM Focal segmental glomerulosclerosis (FSGS) is a common progressive chronic renal disease. Podocyte injury and loss are the postulated pivotal events that trigger FSGS. In this study, the authors aim to examine the evolution of FSGS in murine models histologically, ultrastructurally and immunohistochemically with special emphasis on podocytes and parietal epithelial cells (PECs). MATERIAL AND METHODS FSGS resembling primary FSGS in humans was initiated in Wistar rats using intravenous Adriamycin injections. Blood and urine analysis were performed at 0, 8, and 12 weeks. Both the control kidneys and the test kidneys were harvested at 8 and 12 weeks, examined histologically and ultrastructurally and the findings correlated with the glomerular expression of immunostains specific for podocytes (WT-1) and for activated PECs (CD44). RESULTS FSGS developed in both 8 and 12 weeks test groups showing progressive proteinuria, podocytopathy and segmental glomerular scarring. There was a decrease in the glomerular expression of WT-1 with a concurrent increase in the glomerular expression of CD44, indicating podocyte loss with synchronous increase in activated PECs. The evolving FSGS correlated negatively with podocytes and positively with activated PECs. CONCLUSION Our study shows that with podocyte injury there is podocyte effacement and loss, proteinuria, glomerular segmental adhesion and scarring, all culminating in FSGS. In addition, there is activation, hyperplasia and hypertrophy of PECs. This demonstrates that both podocyte loss and PEC activation promote FSGS. Our findings are consistent with recent investigations. More studies are required to further understand the role of these cells in the evolution of FSGS and subsequently introduce new targeted treatment modalities.
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Affiliation(s)
- Sufia Husain
- a Department of Pathology , College of Medicine, King Saud University , Riyadh , Saudi Arabia
| | - Ibrahim Ginawi
- b Department of Family and Community Medicine , College of Medicine, University of Hail , Hail , Saudi Arabia
| | | | - Hala Kfoury
- a Department of Pathology , College of Medicine, King Saud University , Riyadh , Saudi Arabia
| | - Tariq Eid Al Johani
- a Department of Pathology , College of Medicine, King Saud University , Riyadh , Saudi Arabia
| | - Hanan Hagar
- d Department of Pharmacology , College of Medicine, King Saud University , Riyadh , Saudi Arabia
| | - Lama Raddaoui
- e Intern , College of Medicine, King Faisal University , Riyadh , Saudi Arabia
| | - Mohammed Al Ghonaim
- f Department of Medicine and Nephrology , College of Medicine, King Saud University , Riyadh , Saudi Arabia
| | - Abdulkareem Alsuwaida
- f Department of Medicine and Nephrology , College of Medicine, King Saud University , Riyadh , Saudi Arabia
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163
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Pelletier JH, Kumar KR, Engen R, Bensimhon A, Varner JD, Rheaul MN, Srivastava T, Straatmann C, Silva C, Davis TK, Wenderfer SE, Gibson K, Selewski D, Barcia J, Weng P, Licht C, Jawa N, Kallash M, Foreman JW, Wigfall DR, Chua AN, Chambers E, Hornik CP, Brewer ED, Nagaraj SK, Greenbaum LA, Gbadegesin RA. Recurrence of nephrotic syndrome following kidney transplantation is associated with initial native kidney biopsy findings. Pediatr Nephrol 2018; 33:1773-1780. [PMID: 29982878 PMCID: PMC6129203 DOI: 10.1007/s00467-018-3994-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 05/25/2018] [Accepted: 06/05/2018] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND OBJECTIVES Steroid-resistant nephrotic syndrome (SRNS) due to focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) is a leading cause of end-stage kidney disease in children. Recurrence of primary disease following transplantation is a major cause of allograft loss. The clinical determinants of disease recurrence are not completely known. Our objectives were to determine risk factors for recurrence of FSGS/MCD following kidney transplantation and factors that predict response to immunosuppression following recurrence. METHODS Multicenter study of pediatric patients with kidney transplants performed for ESKD due to SRNS between 1/2006 and 12/2015. Demographics, clinical course, and biopsy data were collected. Patients with primary-SRNS (PSRNS) were defined as those initially resistant to corticosteroid therapy at diagnosis, and patients with late-SRNS (LSRNS) as those initially responsive to steroids who subsequently developed steroid resistance. We performed logistic regression to determine risk factors associated with nephrotic syndrome (NS) recurrence. RESULTS We analyzed 158 patients; 64 (41%) had recurrence of NS in their renal allograft. Disease recurrence occurred in 78% of patients with LSRNS compared to 39% of those with PSRNS. Patients with MCD on initial native kidney biopsy had a 76% recurrence rate compared with a 40% recurrence rate in those with FSGS. Multivariable analysis showed that MCD histology (OR; 95% CI 5.6; 1.3-23.7) compared to FSGS predicted disease recurrence. CONCLUSIONS Pediatric patients with MCD and LSRNS are at higher risk of disease recurrence following kidney transplantation. These findings may be useful for designing studies to test strategies for preventing recurrence.
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Affiliation(s)
- Jonathan H. Pelletier
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | - Karan R. Kumar
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | - Rachel Engen
- Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, Illinois and Children’s Hospital Seattle, Washington
| | - Adam Bensimhon
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | - Jennifer D. Varner
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | | | | | | | - Cynthia Silva
- Connecticut Children’s Medical Center, Hartford, Connecticut
| | | | - Scott E. Wenderfer
- Baylor College of Medicine, and Texas Children’s Hospital, Houston, Texas
| | | | | | - John Barcia
- University of Virginia Children’s Hospital, Charlottesville, Virginia
| | - Patricia Weng
- Mattel Children’s Hospital University of California, Los Angeles, California
| | | | - Natasha Jawa
- The Hospital for Sick Children, Toronto, Ontario, Canada
| | | | - John W. Foreman
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | - Delbert R. Wigfall
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | - Annabelle N. Chua
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | - Eileen Chambers
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | - Christoph P. Hornik
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | - Eileen D. Brewer
- Baylor College of Medicine, and Texas Children’s Hospital, Houston, Texas
| | - Shashi K. Nagaraj
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC
| | | | - Rasheed A. Gbadegesin
- Department of Pediatrics, Divisions of Nephrology and Critical Care Duke University Medical Center, Durham, NC,To whom correspondence should be addressed: Rasheed Gbadegesin, Department of Pediatrics, Divisions of Nephrology, Duke University Medical Center, Durham, NC 27710, Phone: +19196815543,
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164
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Choi YJ, Saba JD. Sphingosine phosphate lyase insufficiency syndrome (SPLIS): A novel inborn error of sphingolipid metabolism. Adv Biol Regul 2018; 71:128-140. [PMID: 30274713 DOI: 10.1016/j.jbior.2018.09.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 09/12/2018] [Accepted: 09/12/2018] [Indexed: 02/06/2023]
Abstract
Sphingosine-1-phosphate lyase (SPL) is an intracellular enzyme that controls the final step in the sphingolipid degradative pathway, the only biochemical pathway for removal of sphingolipids. Specifically, SPL catalyzes the cleavage of sphingosine 1-phosphate (S1P) at the C2-3 carbon bond, resulting in its irreversible degradation to phosphoethanolamine (PE) and hexadecenal. The substrate of the reaction, S1P, is a bioactive sphingolipid metabolite that signals through a family of five G protein-coupled S1P receptors (S1PRs) to mediate biological activities including cell migration, cell survival/death/proliferation and cell extrusion, thereby contributing to development, physiological functions and - when improperly regulated - the pathophysiology of disease. In 2017, several groups including ours reported a novel childhood syndrome that featured a wide range of presentations including fetal hydrops, steroid-resistant nephrotic syndrome (SRNS), primary adrenal insufficiency (PAI), rapid or insidious neurological deterioration, immunodeficiency, acanthosis and endocrine abnormalities. In all cases, the disease was attributed to recessive mutations in the human SPL gene, SGPL1. We now refer to this condition as SPL Insufficiency Syndrome, or SPLIS. Some features of this new sphingolipidosis were predicted by the reported phenotypes of Sgpl1 homozygous null mice that serve as vertebrate SPLIS disease models. However, other SPLIS features reveal previously unrecognized roles for SPL in human physiology. In this review, we briefly summarize the biochemistry, functions and regulation of SPL, the main clinical and biochemical features of SPLIS and what is known about the pathophysiology of this condition from murine and cell models. Lastly, we consider potential therapeutic strategies for the treatment of SPLIS patients.
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Affiliation(s)
- Youn-Jeong Choi
- UCSF Benioff Children's Hospital Oakland, Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA, 94609, USA
| | - Julie D Saba
- UCSF Benioff Children's Hospital Oakland, Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA, 94609, USA.
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165
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Zhang L, Chen XP, Qin H, Jiang L, Qin YH. ATRA attenuate proteinuria via downregulation of TRPC6 in glomerulosclerosis rats induced by adriamycin. Ren Fail 2018; 40:266-272. [PMID: 29619864 PMCID: PMC6014515 DOI: 10.1080/0886022x.2018.1456459] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Objective: In this research, we explored the molecular mechanism of proteinuria in glomerulosclerosis rats and the protective effects of ATRA. Methods: This research set up three groups: SHO group, GS group, and ATRA group (15 mg/(kg d), Sigma, St. Louis, MO). The serum creatinine (Scr), urea nitrogen (BUN), and 24-h proteinuria were detected 12 weeks after administration of ATRA. The pathological and ultrastructure changes were observed under light microscope and transmission electron microscope. The protein expression of TGF-β1 and Col-IV in glomerulus was detected by immunohitochemistry method. The mRNA and the protein expression of glomerular TRPC6 were detected by RT-PCR and Western blot. Results: In the rat model of GS, the expressions of TRPC6 were significantly elevated compared with the normal rat group; however, the use of ATRA down-regulated the expression of TRPC6 in the glomeruli and attenuated glomerulosclerosis and proteinuria. Scr and BUN were also improved by the treatment of ATRA. Conclusions: Our results demonstrated that ATRA could ameliorate glomerulosclerosis and proteinuria in GS, which may be related to suppressed expression of TRPC6.
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Affiliation(s)
- Lei Zhang
- a Department of Pediatric Nephrology , The First Affiliated Hospital of GuangXi Medical University , Nanning , China.,b Department of Pediatric , Affiliated Hospital of Hebei University , Baoding , China
| | - Xiu-Ping Chen
- a Department of Pediatric Nephrology , The First Affiliated Hospital of GuangXi Medical University , Nanning , China
| | - He Qin
- a Department of Pediatric Nephrology , The First Affiliated Hospital of GuangXi Medical University , Nanning , China
| | - Ling Jiang
- a Department of Pediatric Nephrology , The First Affiliated Hospital of GuangXi Medical University , Nanning , China
| | - Yuan-Han Qin
- a Department of Pediatric Nephrology , The First Affiliated Hospital of GuangXi Medical University , Nanning , China
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166
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Wong AY, John RM. Diagnosis and primary care management of focal segmental glomerulosclerosis in children. Nurse Pract 2018; 43:28-37. [PMID: 30134435 DOI: 10.1097/01.npr.0000544275.97385.73] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS) is a pattern of kidney damage that can occur in individuals at any age, including children. Pediatric patients with FSGS require medication monitoring, growth, and psychological health. This article discusses the NP's role in the clinical presentation, diagnostic workup, and treatment of FSGS in pediatric patients.
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Affiliation(s)
- Angela Y Wong
- Angela Y. Wong is a pediatric NP at Maimonides Children's Hospital, Brooklyn, N.Y. Rita Marie John is a PNP program director and associate professor of nursing at Columbia University Medical Center, Columbia University School of Nursing, New York, N.Y
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167
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Tao J, Mariani L, Eddy S, Maecker H, Kambham N, Mehta K, Hartman J, Wang W, Kretzler M, Lafayette RA. JAK-STAT signaling is activated in the kidney and peripheral blood cells of patients with focal segmental glomerulosclerosis. Kidney Int 2018; 94:795-808. [PMID: 30093081 DOI: 10.1016/j.kint.2018.05.022] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Revised: 05/14/2018] [Accepted: 05/17/2018] [Indexed: 10/28/2022]
Abstract
Focal segmental glomerular sclerosis (FSGS) is a devastating disease with limited treatment options and poor prognosis. Activated JAK-STAT signaling has been implicated in other kidney diseases. Since new technologies allow us to better evaluate changes in systemic and renal JAK-STAT activity as it relates to kidney function, we examined this in 106 patients with biopsy-proven FSGS compared to 47 healthy control individuals. Peripheral immune function was assessed in peripheral blood mononuclear cells by phosphoflow studies before and after cytokine stimulation. Kidney JAK-STAT activity was measured by immunofluorescence and by transcriptomics. A STAT1 activity score was calculated by evaluating message status of downstream targets of pSTAT 1. Peripheral blood mononuclear cells were found to be upregulated in terms of pSTAT production at baseline in FSGS and to have limited reserve to respond to various cytokines. Increased staining for components of the JAK-STAT system in FSGS by microscopy was found. Furthermore, we found transcriptomic evidence for activation of JAK-STAT that increased pSTAT 1 and pSTAT 3 in glomerular and tubulointerstitial sections of the kidney. Some of these changes were associated with the likelihood of remission of proteinuria and progression of disease. JAK-STAT signaling is altered in patients with FSGS as compared to healthy controls with activated peripheral immune cells, increased message in the kidney and increased activated proteins in the kidney. Thus, our findings support immune activation in this disease and point to the JAK-STAT pathway as a potential target for treatment of FSGS.
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Affiliation(s)
- Jianling Tao
- Stanford University Medical Center, Stanford, California, USA
| | - Laura Mariani
- University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Sean Eddy
- University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Holden Maecker
- Stanford University Medical Center, Stanford, California, USA
| | - Neeraja Kambham
- Stanford University Medical Center, Stanford, California, USA
| | - Kshama Mehta
- Stanford University Medical Center, Stanford, California, USA
| | - John Hartman
- University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Weiqi Wang
- Stanford University Medical Center, Stanford, California, USA
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168
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Cellular and molecular mechanisms of kidney fibrosis. Mol Aspects Med 2018; 65:16-36. [PMID: 29909119 DOI: 10.1016/j.mam.2018.06.002] [Citation(s) in RCA: 294] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 06/12/2018] [Indexed: 12/14/2022]
Abstract
Renal fibrosis is the final pathological process common to any ongoing, chronic kidney injury or maladaptive repair. It is considered as the underlying pathological process of chronic kidney disease (CKD), which affects more than 10% of world population and for which treatment options are limited. Renal fibrosis is defined by excessive deposition of extracellular matrix, which disrupts and replaces the functional parenchyma that leads to organ failure. Kidney's histological structure can be divided into three main compartments, all of which can be affected by fibrosis, specifically termed glomerulosclerosis in glomeruli, interstitial fibrosis in tubulointerstitium and arteriosclerosis and perivascular fibrosis in vasculature. In this review, we summarized the different appearance, cellular origin and major emerging processes and mediators of fibrosis in each compartment. We also depicted and discussed the challenges in translation of anti-fibrotic treatment to clinical practice and discuss possible solutions and future directions.
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169
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Spires D, Ilatovskaya DV, Levchenko V, North PE, Geurts AM, Palygin O, Staruschenko A. Protective role of Trpc6 knockout in the progression of diabetic kidney disease. Am J Physiol Renal Physiol 2018; 315:F1091-F1097. [PMID: 29923767 DOI: 10.1152/ajprenal.00155.2018] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Diabetic kidney disease (DKD) is a chronic kidney pathology that leads to end-stage renal disease. Previous studies from our laboratory indicate that there is an association between the development of DKD and the transient receptor potential canonical 6 (TRPC6) channel. Trpc6 expression and activity were increased in the streptozotocin (STZ)-treated Dahl Salt-sensitive (Dahl SS) rat, an established model of type 1 diabetes. Here, using a Trpc6 knockout created on the Dahl SS rat background (SSTrpc6-/-), we test the hypothesis that the absence of Trpc6 will protect podocytes and kidney function during the development of DKD. Four groups of animals (control SSWT, SSTrpc6-/-, STZ-treated SSWT, and STZ-SSTrpc6-/-) were utilized in this study. Diabetes development was monitored for 11 wk after STZ injection with periodic weight, glucose, and urinary output measurements. There was an increase in albuminuria and glomerular injury following STZ treatment, which was not different between Dahl SS and SSTrpc6-/- groups. Western blot analysis revealed elevated levels of nephrin in urine samples of STZ-SSWT rats, which was higher compared with STZ-SSTrpc6-/- rats. Furthermore, pathological increases in basal [Ca2+]i levels and foot process damage of podocytes during the development of DKD was attenuated in the STZ-SSTrpc6-/- compared with STZ-SSWT rats. Overall, our data indicate that TRPC6 channel inhibition may have at least partial renoprotective effects, which could lead to the development of new pharmacological tools to treat or prevent the progression of DKD.
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Affiliation(s)
- Denisha Spires
- Department of Physiology, Medical College of Wisconsin , Milwaukee, Wisconsin
| | - Daria V Ilatovskaya
- Department of Physiology, Medical College of Wisconsin , Milwaukee, Wisconsin.,Medical University of South Carolina, Department of Medicine, Charleston, South Carolina
| | - Vladislav Levchenko
- Department of Physiology, Medical College of Wisconsin , Milwaukee, Wisconsin
| | - Paula E North
- Department of Pathology, Medical College of Wisconsin , Milwaukee, Wisconsin
| | - Aron M Geurts
- Department of Physiology, Medical College of Wisconsin , Milwaukee, Wisconsin
| | - Oleg Palygin
- Department of Physiology, Medical College of Wisconsin , Milwaukee, Wisconsin
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170
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Anigilaje EA. A Putative Role of Apolipoprotein L1 Polymorphism in Renal Parenchymal Scarring Following Febrile Urinary Tract Infection in Nigerian Under-Five Children: Proposal for a Case-Control Association Study. JMIR Res Protoc 2018; 7:e156. [PMID: 29903699 PMCID: PMC6024104 DOI: 10.2196/resprot.9514] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 03/23/2018] [Accepted: 04/10/2018] [Indexed: 01/13/2023] Open
Abstract
Background Although urinary tract infection (UTI) resolves with prompt treatment in a majority of children, some children, especially those aged less than 5 years, also develop renal parenchymal scarring (RPS). RPS causes high blood pressure that may lead to severe chronic kidney disease and end-stage renal disease (ESRD). Although the risk of UTI is higher in white children than in black children, it is unknown whether RPS is more common in white children than in black children as data are scarce in this regard. A common genetic predisposition to kidney disease in African Americans and the sub-Saharan African blacks is the possession of apolipoprotein L1 (APOL1). APOL1 risk variants regulate the production of APOL1. APOL1 circulates in the blood, and it is also found in the kidney tissue. While circulating, APOL1 kills the trypanosome parasites; an increased APOL1 in kidney tissues, under the right environmental conditions, can also result in the death of kidney tissue (vascular endothelium, the podocytes, proximal tubules, and arterial cells), which, ultimately, is replaced by fibrous tissue. APOL1 may influence the development of RPS, as evidence affirms that its expression is increased in kidney tissue following UTI caused by bacteria. Thus, UTI may be a putative environmental risk factor responsible for APOL1-induced kidney injury. Objective The aim of this proposal was to outline a study that seeks to determine if the possession of two copies of either G1 or G2 APOL1 variant increases the risk of having RPS, 6 months following a febrile UTI among Nigerian under-five children. Methods This case-control association study seeks to determine whether the risk of RPS from febrile UTI is conditional on having 2 APOL1 risk alleles (either G1 or G2). Cases will be children with a confirmed RPS following a febrile UTI. Controls will be age-, gender-, and ethnic-matched children with a febrile UTI but without RPS. Children with vesicoureteral reflux and other congenital anomalies of the urinary tract are to be excluded. Association between predictor variables (ethnicity, APOL1 G1 or G2, and others) and RPS will be tested at bivariate logistic regression analyses. Predictors that attained significance at a P value of ˂.05 will be considered for multiple logistic regressions. Likelihood-based tests will be used for hypothesis testing. Estimation will be done for the effect size for each of the APOL1 haplotypes using a generalized linear model. Results The study is expected to last for 3 years. Conclusions The study is contingent on having a platform for undergoing a research-based PhD program in any willing university in Europe or elsewhere. The findings of this study will be used to improve the care of African children who may develop RPS following febrile UTI. Registered Report Identifier RR1-10.2196/9514
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Affiliation(s)
- Emmanuel Ademola Anigilaje
- Nephrology Unit, Department of Paediatrics, College of Health Sciences, University of Abuja, Abuja, Nigeria
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171
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Bertelli R, Bonanni A, Caridi G, Canepa A, Ghiggeri GM. Molecular and Cellular Mechanisms for Proteinuria in Minimal Change Disease. Front Med (Lausanne) 2018; 5:170. [PMID: 29942802 PMCID: PMC6004767 DOI: 10.3389/fmed.2018.00170] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 05/15/2018] [Indexed: 12/15/2022] Open
Abstract
Minimal Change Disease (MCD) is a clinical condition characterized by acute nephrotic syndrome, no evident renal lesions at histology and good response to steroids. However, frequent recurrence of the disease requires additional therapies associated with steroids. Such multi-drug dependence and frequent relapses may cause disease evolution to focal and segmental glomerulosclerosis (FSGS) over time. The differences between the two conditions are not well defined, since molecular mechanisms may be shared by the two diseases. In some cases, genetic analysis can make it possible to distinguish MCD from FSGS; however, there are cases of overlap. Several hypotheses on mechanisms underlying MCD and potential molecular triggers have been proposed. Most studies were conducted on animal models of proteinuria that partially mimic MCD and may be useful to study glomerulosclerosis evolution; however, they do not demonstrate a clear-cut separation between MCD and FSGS. Puromycin Aminonucleoside and Adriamycin nephrosis are models of glomerular oxidative damage, characterized by loss of glomerular basement membrane polyanions resembling MCD at the onset and, at more advanced stages, by glomerulosclerosis resembling FSGS. Also Buffalo/Mna rats present initial lesions of MCD, subsequently evolving to FSGS; this mechanism of renal damage is clearer since this rat strain inherits the unique characteristic of overexpressing Th2 cytokines. In Lipopolysaccharide nephropathy, an immunological condition of renal toxicity linked to B7-1(CD80), mice develop transient proteinuria that lasts a few days. Overall, animal models are useful and necessary considering that they reproduce the evolution from MCD to FSGS that is, in part, due to persistence of proteinuria. The role of T/Treg/Bcells on human MCD has been discussed. Many cytokines, immunomodulatory mechanisms, and several molecules have been defined as a specific cause of proteinuria. However, the hypothesis of a single cell subset or molecule as cause of MCD is not supported by research and an interactive process seems more logical. The implication or interactive role of oxidants, Th2 cytokines, Th17, Tregs, B7-1(CD80), CD40/CD40L, c-Mip, TNF, uPA/suPAR, Angiopoietin-like 4 still awaits a definitive confirmation. Whole genome sequencing studies could help to define specific genetic features that justify a definition of MCD as a “clinical-pathology-genetic entity.”
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Affiliation(s)
| | | | | | - Alberto Canepa
- Nephrology, Dialysis, Transplantation Unit, Integrated Department of Pediatrics and Hemato-Oncology Sciences, Istituto Giannina Gaslini IRCCS, Genoa, Italy
| | - G M Ghiggeri
- Laboratory of Molecular Nephrology, Genoa, Italy.,Nephrology, Dialysis, Transplantation Unit, Integrated Department of Pediatrics and Hemato-Oncology Sciences, Istituto Giannina Gaslini IRCCS, Genoa, Italy
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172
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Campbell KN, Tumlin JA. Protecting Podocytes: A Key Target for Therapy of Focal Segmental Glomerulosclerosis. Am J Nephrol 2018; 47 Suppl 1:14-29. [PMID: 29852493 DOI: 10.1159/000481634] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Focal segmental glomerulosclerosis (FSGS) is a histologic pattern of injury demonstrated by renal biopsy that can arise from a diverse range of causes and mechanisms. It has an estimated incidence of 7 per 1 million and is the most common primary glomerular disorder leading to end-stage renal disease in the United States. This review focuses on damage to the podocyte and the consequences of this injury in patients with FSGS, the genetics of FSGS, and approaches to treatment with a focus on the effects on podocytes. SUMMARY The podocyte is central to the glomerular filtration barrier and is particularly vulnerable because of its highly differentiated post-mitotic phenotype. The progressive structural changes involved in the pathology of FSGS include podocyte foot process effacement, death of podocytes and exposure of the glomerular basement membrane, filtration of nonspecific plasma proteins, expansion of capillaries, misdirected filtration at points of synechiae, and mesangial matrix proliferation. Although damage to and death of podocytes can result from single-gene disorders, evidence also suggests a role for soluble factors, such as soluble urokinase-type plasminogen activator receptor, cardiotrophin-like cytokine-1, and anti-CD40 antibodies, that promote FSGS recurrence post transplant. Several classes of medications, including corticosteroids, calcineurin inhibitors, endothelin receptor antagonists, adrenocorticotropic hormone, and rituximab, have been shown to be effective for the treatment of FSGS and have been demonstrated to have significant protective effects on podocytes. Key Messages: Greater understanding of podocyte biology is essential to the identification of new treatment targets and medications for the management of patients with FSGS.
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Affiliation(s)
- Kirk N Campbell
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - James A Tumlin
- Department of Medicine, UT College of Medicine, University of Tennessee, Chattanooga, Tennessee, USA
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Georgianos PI, Divani M, Eleftheriadis T, Mertens PR, Liakopoulos V. SGLT-2 inhibitors in Diabetic Kidney Disease: What Lies Behind their Renoprotective Properties? Curr Med Chem 2018; 26:5564-5578. [PMID: 29792136 DOI: 10.2174/0929867325666180524114033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 05/13/2018] [Accepted: 05/21/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Despite optimal management of diabetic kidney disease (DKD) with intensive glycemic control and administration of agents blocking the renin-angiotensinaldosterone- system, the residual risk for nephropathy progression to end-stage-renal-disease (ESRD) remains high. Sodium-glucose co-transporter type 2 (SGLT-2)-inhibitors represent a newly-introduced anti-diabetic drug class with pleiotropic actions extending above their glucose-lowering efficacy. Herein, we provide an overview of preclinical and clinical-trial evidence supporting a protective effect of SGLT-2 inhibitors on DKD. METHODS A systematic literature search of bibliographic databases was conducted to identify preclinical studies and randomized trials evaluating the effects SGLT-2 inhibitors on DKD. RESULTS Preclinical studies performed in animal models of DKD support the renoprotective action of SGLT-2 inhibitors showing that these agents exert albuminuria-lowering effects and reverse glomerulosclerosis. The renoprotective action of SGLT-2 inhibitors is strongly supported by human studies showing that these agents prevent the progression of albuminuria and retard nephropathy progression to ESRD. This beneficial effect of SGLT-2 inhibitors is not fully explained by their glucose-lowering properties. Attenuation of glomerular hyperfiltration and improvement in a number of surrogate risk factors, including associated reduction in systemic blood pressure, body weight, and serum uric acid levels may represent plausible mechanistic explanations for the cardio-renal protection offered by SGLT-2 inhibitors. Furthermore, the tubular cell metabolism seems to be altered towards a ketone-prone pathway with protective activities. CONCLUSION SGLT-2 inhibition emerges as a novel therapeutic approach of diabetic with anticipated benefits towards cardio-renal risk reduction. Additional research efforts are clearly warranted to elucidate this favorable effect in patients with overt DKD.
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Affiliation(s)
- Panagiotis I Georgianos
- Section of Nephrology and Hypertension, 1st Department of Medicine, AHEPA Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Maria Divani
- Section of Nephrology and Hypertension, 1st Department of Medicine, AHEPA Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | | | - Peter R Mertens
- Clinic of Nephrology and Hypertension, Diabetes and Endocrinology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Vassilios Liakopoulos
- Section of Nephrology and Hypertension, 1st Department of Medicine, AHEPA Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.,Clinic of Nephrology and Hypertension, Diabetes and Endocrinology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
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174
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Sato Y, Tsukaguchi H, Morita H, Higasa K, Tran MTN, Hamada M, Usui T, Morito N, Horita S, Hayashi T, Takagi J, Yamaguchi I, Nguyen HT, Harada M, Inui K, Maruta Y, Inoue Y, Koiwa F, Sato H, Matsuda F, Ayabe S, Mizuno S, Sugiyama F, Takahashi S, Yoshimura A. A mutation in transcription factor MAFB causes Focal Segmental Glomerulosclerosis with Duane Retraction Syndrome. Kidney Int 2018; 94:396-407. [PMID: 29779709 DOI: 10.1016/j.kint.2018.02.025] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 01/24/2018] [Accepted: 02/08/2018] [Indexed: 01/02/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS) is a leading cause of end-stage renal disease in children and adults. Genetic factors significantly contribute to early-onset FSGS, but the etiologies of most adult cases remain unknown. Genetic studies of monogenic syndromic FSGS exhibiting extra-renal manifestations have uncovered an unexpected biological role for genes in the development of both podocytes and other cellular lineages. To help define these roles, we studied two unrelated families with FSGS associated with Duane Retraction Syndrome, characterized by impaired horizontal eye movement due to cranial nerve malformation. All four affected individuals developed FSGS and Duane Retraction Syndrome in their first to second decade of life, manifested as restricted abduction together with globe retraction and narrowed palpebral fissure on attempted adduction. Hypoplasia of the abducens nerves and hearing impairment occurred in severely affected individuals. Genetic analyses revealed that affected individuals harbor a rare heterozygous substitution (p.Leu239Pro) in MAFB, a leucine zipper transcription factor. Luciferase assays with cultured monocytes indicated that the substitution significantly reduced transactivation of the F4/80 promoter, the known MAFB recognition element. Additionally, immunohistochemistry indicated reduced MAFB expression in the podocytes of patients. Structural modeling suggested that the p.Leu239Pro substitution in the DNA-binding domain possibly interferes with the stability of the adjacent zinc finger. Lastly, podocytes in neonatal mice with p.Leu239Pro displayed impaired differentiation. Thus, MAFB mutations impair development and/or maintenance of podocytes, abducens neurons and the inner ear. The interactions between MAFB and regulatory elements in these developing organs are likely highly specific based on spatiotemporal requirements.
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Affiliation(s)
- Yoshinori Sato
- Division of Nephrology, Department of Medicine, Showa University Fujigaoka Hospital, Fujigaoka, Japan
| | - Hiroyasu Tsukaguchi
- Second Department of Internal Medicine, Kansai Medical University, Hirakata, Japan.
| | - Hiroyuki Morita
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Koichiro Higasa
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Mai Thi Nhu Tran
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Michito Hamada
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Toshiaki Usui
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan; Department of Nephrology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Naoki Morito
- Department of Nephrology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Shoichiro Horita
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takao Hayashi
- Department of Ophthalmology, School of Medicine, Teikyo University, Tokyo, Japan
| | - Junko Takagi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Izumi Yamaguchi
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Huan Thanh Nguyen
- Second Department of Internal Medicine, Kansai Medical University, Hirakata, Japan
| | - Masayo Harada
- Department of Clinical Anatomy, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kiyoko Inui
- Division of Nephrology, Department of Medicine, Showa University Fujigaoka Hospital, Fujigaoka, Japan
| | - Yuichi Maruta
- Division of Nephrology, Department of Medicine, Showa University Fujigaoka Hospital, Fujigaoka, Japan
| | - Yoshihiko Inoue
- Division of Nephrology, Department of Medicine, Showa University Fujigaoka Hospital, Fujigaoka, Japan
| | - Fumihiko Koiwa
- Division of Nephrology, Department of Medicine, Showa University Fujigaoka Hospital, Fujigaoka, Japan
| | - Hiroshi Sato
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Fumihiko Matsuda
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Shinya Ayabe
- Experimental Animal Division, RIKEN BioResource Center, Tsukuba, Japan
| | - Seiya Mizuno
- Laboratory Animal Resource Center, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Fumihiro Sugiyama
- Laboratory Animal Resource Center, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Satoru Takahashi
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan; Laboratory Animal Resource Center, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan; International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan; Life Science Center of Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba, Japan
| | - Ashio Yoshimura
- Division of Nephrology, Department of Medicine, Showa University Fujigaoka Hospital, Fujigaoka, Japan
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175
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Structure of the receptor-activated human TRPC6 and TRPC3 ion channels. Cell Res 2018; 28:746-755. [PMID: 29700422 DOI: 10.1038/s41422-018-0038-2] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 03/22/2018] [Accepted: 04/02/2018] [Indexed: 12/22/2022] Open
Abstract
TRPC6 and TRPC3 are receptor-activated nonselective cation channels that belong to the family of canonical transient receptor potential (TRPC) channels. They are activated by diacylglycerol, a lipid second messenger. TRPC6 and TRPC3 are involved in many physiological processes and implicated in human genetic diseases. Here we present the structure of human TRPC6 homotetramer in complex with a newly identified high-affinity inhibitor BTDM solved by single-particle cryo-electron microscopy to 3.8 Å resolution. We also present the structure of human TRPC3 at 4.4 Å resolution. These structures show two-layer architectures in which the bell-shaped cytosolic layer holds the transmembrane layer. Extensive inter-subunit interactions of cytosolic domains, including the N-terminal ankyrin repeats and the C-terminal coiled-coil, contribute to the tetramer assembly. The high-affinity inhibitor BTDM wedges between the S5-S6 pore domain and voltage sensor-like domain to inhibit channel opening. Our structures uncover the molecular architecture of TRPC channels and provide a structural basis for understanding the mechanism of these channels.
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176
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Abstract
Acute kidney injury (AKI) and chronic kidney disease (CKD) are worldwide public health problems affecting millions of people and have rapidly increased in prevalence in recent years. Due to the multiple causes of renal failure, many animal models have been developed to advance our understanding of human nephropathy. Among these experimental models, rodents have been extensively used to enable mechanistic understanding of kidney disease induction and progression, as well as to identify potential targets for therapy. In this review, we discuss AKI models induced by surgical operation and drugs or toxins, as well as a variety of CKD models (mainly genetically modified mouse models). Results from recent and ongoing clinical trials and conceptual advances derived from animal models are also explored.
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Affiliation(s)
- Yin-Wu Bao
- Kidney Disease Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou Zhejiang 310058, China. .,Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou Zhejiang 310058, China
| | - Yuan Yuan
- Kidney Disease Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou Zhejiang 310058, China. .,Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou Zhejiang 310058, China
| | - Jiang-Hua Chen
- Kidney Disease Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou Zhejiang 310058, China.
| | - Wei-Qiang Lin
- Kidney Disease Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou Zhejiang 310058, China. .,Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou Zhejiang 310058, China
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177
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Immunology of idiopathic nephrotic syndrome. Pediatr Nephrol 2018; 33:573-584. [PMID: 28451893 DOI: 10.1007/s00467-017-3677-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 04/05/2017] [Accepted: 04/07/2017] [Indexed: 12/18/2022]
Abstract
The pathogenesis of idiopathic nephrotic syndrome (INS) is as yet unknown, but several lines of evidence indicate that the immune system may play a crucial pathogenic role in non-genetic INS. The most important of these are, first, the effectiveness of therapy based on immunosuppression and, second, a vast body of data derived both from experimental models and from patient studies that implicate T cells and more recently B cells as major players in INS pathogenesis. However, recent findings also suggest a direct role of podocytes as drivers of the disease process, and the interplay between the glomerulus and the immune system is still being elucidated. In this review we provide an overview of current knowledge on the role of different components of the immune system in determining disease. Advances in our understanding of the pathogenesis of INS may help drive new, more tailored therapeutic approaches.
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178
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Embry AE, Liu Z, Henderson JM, Byfield FJ, Liu L, Yoon J, Wu Z, Cruz K, Moradi S, Gillombardo CB, Hussain RZ, Doelger R, Stuve O, Chang AN, Janmey PA, Bruggeman LA, Miller RT. Similar Biophysical Abnormalities in Glomeruli and Podocytes from Two Distinct Models. J Am Soc Nephrol 2018; 29:1501-1512. [PMID: 29572404 DOI: 10.1681/asn.2017050475] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 02/21/2018] [Indexed: 01/19/2023] Open
Abstract
Background FSGS is a pattern of podocyte injury that leads to loss of glomerular function. Podocytes support other podocytes and glomerular capillary structure, oppose hemodynamic forces, form the slit diaphragm, and have mechanical properties that permit these functions. However, the biophysical characteristics of glomeruli and podocytes in disease remain unclear.Methods Using microindentation, atomic force microscopy, immunofluorescence microscopy, quantitative RT-PCR, and a three-dimensional collagen gel contraction assay, we studied the biophysical and structural properties of glomeruli and podocytes in chronic (Tg26 mice [HIV protein expression]) and acute (protamine administration [cytoskeletal rearrangement]) models of podocyte injury.Results Compared with wild-type glomeruli, Tg26 glomeruli became progressively more deformable with disease progression, despite increased collagen content. Tg26 podocytes had disordered cytoskeletons, markedly abnormal focal adhesions, and weaker adhesion; they failed to respond to mechanical signals and exerted minimal traction force in three-dimensional collagen gels. Protamine treatment had similar but milder effects on glomeruli and podocytes.Conclusions Reduced structural integrity of Tg26 podocytes causes increased deformability of glomerular capillaries and limits the ability of capillaries to counter hemodynamic force, possibly leading to further podocyte injury. Loss of normal podocyte mechanical integrity could injure neighboring podocytes due to the absence of normal biophysical signals required for podocyte maintenance. The severe defects in podocyte mechanical behavior in the Tg26 model may explain why Tg26 glomeruli soften progressively, despite increased collagen deposition, and may be the basis for the rapid course of glomerular diseases associated with severe podocyte injury. In milder injury (protamine), similar processes occur but over a longer time.
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Affiliation(s)
- Addie E Embry
- Department of Internal Medicine, Division of Nephrology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Zhenan Liu
- Department of Internal Medicine, Division of Nephrology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Joel M Henderson
- Department of Pathology, Boston University School of Medicine, Boston, Massachusetts
| | - F Jefferson Byfield
- Department of Physiology and Biophysics, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Liping Liu
- Department of Internal Medicine, Division of Nephrology, University of Texas Southwestern Medical Center, Dallas, Texas.,Department of Medicine, Dallas Veterans Affairs Medical Center, Dallas, Texas
| | - Joonho Yoon
- Department of Internal Medicine, Division of Nephrology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Zhenzhen Wu
- Department of Medicine, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Katrina Cruz
- Department of Pathology, Boston University School of Medicine, Boston, Massachusetts
| | - Sara Moradi
- Department of Pathology, Boston University School of Medicine, Boston, Massachusetts
| | | | - Rihanna Z Hussain
- Department of Neurology, University of Texas Southwestern Medical School, Dallas, Texas; and
| | - Richard Doelger
- Department of Neurology, University of Texas Southwestern Medical School, Dallas, Texas; and
| | - Olaf Stuve
- Department of Neurology, University of Texas Southwestern Medical School, Dallas, Texas; and
| | - Audrey N Chang
- Department of Internal Medicine, Division of Nephrology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Paul A Janmey
- Department of Physiology and Biophysics, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Leslie A Bruggeman
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - R Tyler Miller
- Department of Internal Medicine, Division of Nephrology, University of Texas Southwestern Medical Center, Dallas, Texas; .,Department of Medicine, Dallas Veterans Affairs Medical Center, Dallas, Texas
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179
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Hacker B, Schultheiß C, Döring M, Kurzik-Dumke U. Molecular partners of hNOT/ALG3, the human counterpart of the Drosophila NOT and yeast ALG3 gene, suggest its involvement in distinct cellular processes relevant to congenital disorders of glycosylation, cancer, neurodegeneration and a variety of further pathologies. Hum Mol Genet 2018; 27:1858-1878. [DOI: 10.1093/hmg/ddy087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 03/06/2018] [Indexed: 01/04/2023] Open
Affiliation(s)
- Benedikt Hacker
- Laboratory for Comparative Tumour Biology, Institute of Medical Microbiology and Hygiene, University Medical Centre, Johannes Gutenberg University, 55131 Mainz, Germany
| | - Christoph Schultheiß
- Laboratory for Comparative Tumour Biology, Institute of Medical Microbiology and Hygiene, University Medical Centre, Johannes Gutenberg University, 55131 Mainz, Germany
| | - Michael Döring
- Laboratory for Comparative Tumour Biology, Institute of Medical Microbiology and Hygiene, University Medical Centre, Johannes Gutenberg University, 55131 Mainz, Germany
| | - Ursula Kurzik-Dumke
- Laboratory for Comparative Tumour Biology, Institute of Medical Microbiology and Hygiene, University Medical Centre, Johannes Gutenberg University, 55131 Mainz, Germany
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180
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Steiner RW. Increased Single-Nephron GFR in Normal Adults: Too Much of a Good Thing . . . or Maybe Not? Am J Kidney Dis 2018; 71:312-314. [DOI: 10.1053/j.ajkd.2017.11.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Accepted: 11/19/2017] [Indexed: 11/11/2022]
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181
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Feng D, DuMontier C, Pollak MR. Mechanical challenges and cytoskeletal impairments in focal segmental glomerulosclerosis. Am J Physiol Renal Physiol 2018; 314:F921-F925. [PMID: 29363327 DOI: 10.1152/ajprenal.00641.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Focal segmental glomerulosclerosis (FSGS) is a histologically defined form of kidney injury typically mediated by podocyte dysfunction. Podocytes rely on their intricate actin-based cytoskeleton to maintain the glomerular filtration barrier in the face of mechanical challenges resulting from pulsatile blood flow and filtration of this blood flow. This review summarizes the mechanical challenges faced by podocytes in the form of stretch and shear stress, both of which may play a role in the progression of podocyte dysfunction and detachment. It also reviews how podocytes respond to these mechanical challenges in dynamic fashion through rearranging their cytoskeleton, triggering various biochemical pathways, and, in some disease states, altering their morphology in the form of foot process effacement. Furthermore, this review highlights the growing body of evidence identifying several mutations of important cytoskeleton proteins as causes of FSGS. Lastly, it synthesizes the above evidence to show that a better understanding of how these mutations leave podocytes vulnerable to the mechanical challenges they face is essential to better understanding the mechanisms by which they lead to disease. The review concludes with future research directions to fill this gap and some novel techniques with which to pursue these directions.
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Affiliation(s)
- Di Feng
- Division of Nephrology, Department of Medicine, Beth Israel Deaconess Medical Center , Boston, Massachusetts.,Harvard Medical School , Boston, Massachusetts
| | - Clark DuMontier
- Harvard Medical School , Boston, Massachusetts.,Division of Gerontology, Department of Medicine, Beth Israel Deaconess Medical Center , Boston, Massachusetts
| | - Martin R Pollak
- Division of Nephrology, Department of Medicine, Beth Israel Deaconess Medical Center , Boston, Massachusetts.,Harvard Medical School , Boston, Massachusetts
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182
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Stârcea M, Gavrilovici C, Munteanu M, Miron I. Focal segmental glomerulosclerosis in children complicated by posterior reversible encephalopathy syndrome. J Int Med Res 2018; 46:1172-1177. [PMID: 29310486 PMCID: PMC5972267 DOI: 10.1177/0300060517746559] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
An uncommon side effect of cyclosporine A (CsA) use is posterior reversible encephalopathy syndrome (PRES). PRES usually develops because of disturbed capacity of posterior cerebral blood flow to autoregulate an acute rise in blood pressure. We present the case of a 10-year-old girl who was previously diagnosed in our department with focal segmental glomerulosclerosis. She was treated with CsA and developed seizures, progressive loss of consciousness, and visual disturbance on the 7th day of treatment. Brain magnetic resonance imaging showed degeneration of white matter with diffuse demyelination in the parietal and posterior occipital lobes, consistent with the diagnosis of PRES. Cases of PRES reported in children are usually secondary to immunosuppressive therapy in oncological and haematological diseases. Our case is the fifth reported case of focal segmental glomerulosclerosis in children treated with CsA and complicated by PRES. Rapid recognition of PRES and stopping neurotoxic therapy early are essential for a good prognosis.
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Affiliation(s)
- Magdalena Stârcea
- Department of Pediatrics, St. Maria Children's Hospital, University of Medicine and Pharmacy "Grigore T. Popa" Iasi, România
| | - Cristina Gavrilovici
- Department of Pediatrics, St. Maria Children's Hospital, University of Medicine and Pharmacy "Grigore T. Popa" Iasi, România
| | - Mihaela Munteanu
- Department of Pediatrics, St. Maria Children's Hospital, University of Medicine and Pharmacy "Grigore T. Popa" Iasi, România
| | - Ingrith Miron
- Department of Pediatrics, St. Maria Children's Hospital, University of Medicine and Pharmacy "Grigore T. Popa" Iasi, România
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183
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Peng LQ, Zhao H, Liu S, Yuan YP, Yuan CY, Mwamunyi MJ, Pearce D, Yao LJ. Lack of serum- and glucocorticoid-inducible kinase 3 leads to podocyte dysfunction. FASEB J 2018; 32:576-587. [PMID: 28935820 DOI: 10.1096/fj.201700393rr] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Serum- and glucocorticoid-inducible kinase 3 (SGK3) is a downstream mediator of PI3K, which is essential for maintaining the functional integrity of podocytes. However, little is known about the role of SGK3 in podocyte function. Herein, we demonstrated that SGK3 contributes to the maintenance of podocyte integrity. Conditionally immortalized mouse podocyte cells (MPCs) were treated with puromycin aminonucleoside (PAN). PAN treatment inhibited the activity of SGK3 and the expression of podocin. Short hairpin RNA (shRNA)-mediated knockdown of SGK3 also reduced podocin expression in the absence of PAN. Adriamycin (ADR)-treated mice developed proteinuria and had decreased renal glomerular SGK3 expression in comparison to control mice. Consistent with a role for SGK3 in the ADR effect, SGK3 knockout (KO) mice had markedly reduced kidney podocin expression and significantly elevated proteinuria compared with wild-type mice. Electron microscopy revealed that SGK3 KO mice displayed partial effacement of podocyte foot processes. Further, a SGK3 target protein, glycogen synthase kinase-3 (GSK3), was discovered to be dramatically activated in PAN and SGK3 shRNA-treated MPCs and in SGK3 KO mice. Taken together, these data strongly suggest that SGK3 plays a significant role in regulating podocyte function, likely by controlling the expression and activity of GSK3.-Peng, L.-Q., Zhao, H., Liu, S., Yuan, Y.-P., Yuan, C.-Y., Mwamunyi, M.-J., Pearce, D., Yao, L.-J. Lack of serum- and glucocorticoid-inducible kinase 3 leads to podocyte dysfunction.
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Affiliation(s)
- Li-Qin Peng
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hong Zhao
- Department of Trauma Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Song Liu
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ya-Pei Yuan
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Cheng-Yan Yuan
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Mercy-Julian Mwamunyi
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - David Pearce
- Department of Medicine, University of California, San Francisco, San Francisco, California, USA.,Department of Molecular and Cellular Pharmacology, University of California, San Francisco, San Francisco, California, USA
| | - Li-Jun Yao
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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184
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Traditional Chinese Medicine for Refractory Nephrotic Syndrome: Strategies and Promising Treatments. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2018; 2018:8746349. [PMID: 29507594 PMCID: PMC5817219 DOI: 10.1155/2018/8746349] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/03/2017] [Indexed: 12/18/2022]
Abstract
Refractory nephrotic syndrome (RNS) is an immune-related kidney disease with poor clinical outcomes. Standard treatments include corticosteroids as the initial therapy and other immunosuppressants as second-line options. A substantial proportion of patients with RNS are resistant to or dependent on immunosuppressive drugs and often experience unremitting edema and proteinuria, cycles of remission and relapse, and/or serious adverse events due to long-term immunosuppression. Traditional Chinese medicine has a long history of treating complicated kidney diseases and holds great potential for providing effective treatments for RNS. This review describes the Chinese medical theories relating to the pathogenesis of RNS and discusses the strategies and treatment options using Chinese herbal medicine. Available preclinical and clinical evidence strongly supports the integration of traditional Chinese medicine and Western medicine for improving the outcome of RNS. Herbal medicine such as Astragalus membranaceus, Stephania tetrandra S. Moore, and Tripterygium wilfordii Hook F can serve as the alternative therapy when patients fail to respond to immunosuppression or as the complementary therapy to improve therapeutic efficacy and reduce side effects of immunosuppressive agents. Wuzhi capsules (Schisandra sphenanthera extract) with tacrolimus and tetrandrine with corticosteroids are two herb-drug combinations that have shown great promise and warrant further studies.
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185
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Abstract
Life with a solitary functioning kidney (SFK) may be different from that when born with two kidneys. Based on the hyperfiltration hypothesis, a SFK may lead to glomerular damage with hypertension, albuminuria and progression towards end-stage renal disease. As the prognosis of kidney donors was considered to be very good, having a SFK has been considered to be a benign condition. In contrast, our research group has demonstrated that being born with or acquiring a SFK in childhood results in renal injury before adulthood in over 50% of those affected. Most congenital cases will be detected during antenatal ultrasound screening, but up to 38% of cases of unilateral renal agenesis are missed. In about 25-50% of cases of antenatally detected SFK there will be signs of hypertrophy, which could indicate additional nephron formation and is associated with a somewhat reduced risk of renal injury. Additional renal and extrarenal anomalies are frequently detected and may denote a genetic cause for the SFK, even though for the majority of cases no explanation can (yet) be found. The ongoing glomerular hyperfiltration results in renal injury, for which early markers are lacking. Individuals with SFK should avoid obesity and excessive salt intake to limit additional hyperfiltration. As conditions like hypertension, albuminuria and a mildly reduced glomerular filtration rate generally do not result in specific complaints but may pose a threat to long-term health, screening for renal injury in any individual with a SFK would appear to be imperative, starting from infancy. With early treatment, secondary consequences may be diminished, thereby providing the optimal life for anyone born with a SFK.
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186
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Majumder S, Thieme K, Batchu SN, Alghamdi TA, Bowskill BB, Kabir MG, Liu Y, Advani SL, White KE, Geldenhuys L, Tennankore KK, Poyah P, Siddiqi FS, Advani A. Shifts in podocyte histone H3K27me3 regulate mouse and human glomerular disease. J Clin Invest 2017; 128:483-499. [PMID: 29227285 DOI: 10.1172/jci95946] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 10/31/2017] [Indexed: 01/09/2023] Open
Abstract
Histone protein modifications control fate determination during normal development and dedifferentiation during disease. Here, we set out to determine the extent to which dynamic changes to histones affect the differentiated phenotype of ordinarily quiescent adult glomerular podocytes. To do this, we examined the consequences of shifting the balance of the repressive histone H3 lysine 27 trimethylation (H3K27me3) mark in podocytes. Adriamycin nephrotoxicity and subtotal nephrectomy (SNx) studies indicated that deletion of the histone methylating enzyme EZH2 from podocytes decreased H3K27me3 levels and sensitized mice to glomerular disease. H3K27me3 was enriched at the promoter region of the Notch ligand Jag1 in podocytes, and derepression of Jag1 by EZH2 inhibition or knockdown facilitated podocyte dedifferentiation. Conversely, inhibition of the Jumonji C domain-containing demethylases Jmjd3 and UTX increased the H3K27me3 content of podocytes and attenuated glomerular disease in adriamycin nephrotoxicity, SNx, and diabetes. Podocytes in glomeruli from humans with focal segmental glomerulosclerosis or diabetic nephropathy exhibited diminished H3K27me3 and heightened UTX content. Analogous to human disease, inhibition of Jmjd3 and UTX abated nephropathy progression in mice with established glomerular injury and reduced H3K27me3 levels. Together, these findings indicate that ostensibly stable chromatin modifications can be dynamically regulated in quiescent cells and that epigenetic reprogramming can improve outcomes in glomerular disease by repressing the reactivation of developmental pathways.
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Affiliation(s)
- Syamantak Majumder
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Karina Thieme
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Sri N Batchu
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Tamadher A Alghamdi
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Bridgit B Bowskill
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - M Golam Kabir
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Youan Liu
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Suzanne L Advani
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Kathryn E White
- Electron Microscopy Research Services, Newcastle University, Newcastle upon Tyne, United Kingdom
| | | | | | - Penelope Poyah
- Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Ferhan S Siddiqi
- Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Andrew Advani
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
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187
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Grèze C, Garrouste C, Kemeny JL, Philipponnet C, Aniort J, Heng AÉ. [Collapsing focal segmental glomerulosclerosis induced by cytomegalovirus: A case report]. Nephrol Ther 2017; 14:50-53. [PMID: 29191574 DOI: 10.1016/j.nephro.2017.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 04/26/2017] [Accepted: 06/01/2017] [Indexed: 10/18/2022]
Abstract
Focal segmental glomerulosclerosis (FSGS) is a common cause of nephrotic syndrome in child and adult. The collapsing forms are of poor renal prognosis and are usually secondary to viral infections with, first and foremost, the human immunodeficiency virus. Among other viral etiologies, cytomegalovirus (CMV) is an uncommon cause. We report a case of a 32years-old patient with collapsing focal segmental glomerulosclerosis induced by cytomegalovirus with initial acute renal failure and proteinuria at 12.4g/24h. The treatment associated ganciclovir during 7days followed by valganciclovir during 14days and steroids at 1mg/kg/day. Renal function improved and proteinuria decreased with this treatment. Proteinuria increase again 3weeks after valganciclovir discontinuation while CMV Polymerase chain reaction (PCR) was positive. Therefore, valganciclovir has been resumed allowing renal function normalization and decrease in proteinuria to 4g/24h after negative CMVPCR assay after 15weeks. Anti-CMV therapy combined with steroids seems to provide a renal response in case of FSGS induced by CMV even if long-term prognosis stays uncertain.
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Affiliation(s)
- Clarisse Grèze
- Service de néphrologie, CHU Gabriel-Montpied, 58, rue Montalembert, BP 69, 63000 Clermont-Ferrand cedex, France.
| | - Cyril Garrouste
- Service de néphrologie, CHU Gabriel-Montpied, 58, rue Montalembert, BP 69, 63000 Clermont-Ferrand cedex, France
| | - Jean-Louis Kemeny
- Laboratoire d'anatomopathologie, CHU Gabriel-Montpied, 58, rue Montalembert, BP 69, 63000 Clermont-Ferrand cedex, France
| | - Carole Philipponnet
- Service de néphrologie, CHU Gabriel-Montpied, 58, rue Montalembert, BP 69, 63000 Clermont-Ferrand cedex, France
| | - Julien Aniort
- Service de néphrologie, CHU Gabriel-Montpied, 58, rue Montalembert, BP 69, 63000 Clermont-Ferrand cedex, France
| | - Anne-Élisabeth Heng
- Service de néphrologie, CHU Gabriel-Montpied, 58, rue Montalembert, BP 69, 63000 Clermont-Ferrand cedex, France
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188
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Mottl AK, Gasim A, Schober FP, Hu Y, Dunnon AK, Hogan SL, Jennette JC. Segmental Sclerosis and Extracapillary Hypercellularity Predict Diabetic ESRD. J Am Soc Nephrol 2017; 29:694-703. [PMID: 29180393 DOI: 10.1681/asn.2017020192] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 10/24/2017] [Indexed: 01/11/2023] Open
Abstract
Pathogenetic markers of diabetic kidney disease (DKD) progression to ESRD are lacking. We characterized the prognostic value of histologic findings in DKD for time to ESRD in native kidney specimens from biopsies performed from 1995 to 2011 with diabetic glomerulosclerosis as the only glomerular disease diagnosis (n=109). Biopsy specimens were analyzed according to standard methods, including determination of diabetic nephropathy class, as defined by the Renal Pathology Society. Clinical data were extracted from electronic medical records. We used competing risk models, with death as the competing risk, to estimate subdistribution hazard ratios (HRs) for ESRD. All multivariable models included age, sex, black race, baseline eGFR, and baseline proteinuria. Pathologic characteristics achieving P<0.1 were added into successively complex models. ESRD occurred in 56% of patients, and 26% of patients died before reaching ESRD. In univariate analyses, diabetic nephropathy class was not statistically significant in predicting time to ESRD. The final multivariable model (n=106) showed a borderline association between mild mesangial expansion and decreased risk for ESRD (subdistribution HR, 0.64; 95% confidence interval, 0.40 to 1.00). Poor prognostic factors in the final model included segmental sclerosis and extracapillary hypercellularity (subdistribution HR, 2.04; 95% confidence interval, 1.36 to 3.05; and subdistribution HR, 2.21; 95% confidence interval, 1.19 to 4.11, respectively). In conclusion, we identified segmental sclerosis and extracapillary hypercellularity as novel, poor prognostic indicators of time from DKD to ESRD. Whether these indicators represent a distinct pathogenetic phenotype of DKD will require a large study with a broad spectrum of disease severity.
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Affiliation(s)
- Amy K Mottl
- Division of Nephrology and Hypertension, Department of Medicine, and
| | - Adil Gasim
- Division of Nephropathology, Department of Pathology and Laboratory Medicine, University of North Carolina
| | | | - Yichun Hu
- Division of Nephrology and Hypertension, Department of Medicine, and
| | - Askia K Dunnon
- Division of Nephrology and Hypertension, Department of Medicine, and
| | - Susan L Hogan
- Division of Nephrology and Hypertension, Department of Medicine, and
| | - J Charles Jennette
- Division of Nephropathology, Department of Pathology and Laboratory Medicine, University of North Carolina
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189
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Rajasekeran H, Reich HN, Hladunewich MA, Cattran D, Lovshin JA, Lytvyn Y, Bjornstad P, Lai V, Tse J, Cham L, Majumder S, Bowskill BB, Kabir MG, Advani SL, Gibson IW, Sood MM, Advani A, Cherney DZI. Dapagliflozin in focal segmental glomerulosclerosis: a combined human-rodent pilot study. Am J Physiol Renal Physiol 2017; 314:F412-F422. [PMID: 29141939 DOI: 10.1152/ajprenal.00445.2017] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Focal segmental glomerulosclerosis (FSGS) is an important cause of nondiabetic chronic kidney disease (CKD). Sodium-glucose cotransporter 2 inhibition (SGLT2i) therapy attenuates the progression of diabetic nephropathy, but it remains unclear whether SGLT2i provides renoprotection in nondiabetic CKD such as FSGS. The primary aim of this pilot study was to determine the effect of 8 wk of dapagliflozin on glomerular filtration rate (GFR) in humans and in experimental FSGS. Secondary end points were related to changes in renal hemodynamic function, proteinuria, and blood pressure (BP). GFR (inulin) and renal plasma flow (para-aminohippurate), proteinuria, and BP were measured in patients with FSGS ( n = 10), and similar parameters were measured in subtotally nephrectomized (SNx) rats. In response to dapagliflozin, changes in GFR, renal plasma flow, and 24-h urine protein excretion were not statistically significant in humans or rats. Systolic BP (SBP) decreased in SNx rats (196 ± 26 vs. 165 ± 33 mmHg; P < 0.001), whereas changes were not statistically significant in humans (SBP 112.7 ± 8.5 to 112.8 ± 11.2 mmHg, diastolic BP 71.8 ± 6.5 to 69.6 ± 8.4 mmHg; P = not significant), although hematocrit increased (0.40 ± 0.05 to 0.42 ± 0.05%; P = 0.03). In archival kidney tissue from a separate patient cohort, renal parenchymal SGLT2 mRNA expression was decreased in individuals with FSGS compared with controls. Short-term treatment with the SGLT2i dapagliflozin did not modify renal hemodynamic function or attenuate proteinuria in humans or in experimental FSGS. This may be related to downregulation of renal SGLT2 expression. Studies examining the impact of SGLT2i on markers of kidney disease in patients with other causes of nondiabetic CKD are needed.
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Affiliation(s)
- Harindra Rajasekeran
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada.,Department of Physiology, University of Toronto , Toronto, Ontario , Canada
| | - Heather N Reich
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada
| | - Michelle A Hladunewich
- Department of Medicine, Division of Nephrology, Sunnybrook Health Sciences Centre, University of Toronto , Toronto, Ontario , Canada
| | - Daniel Cattran
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada
| | - Julie A Lovshin
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada
| | - Yuliya Lytvyn
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada
| | - Petter Bjornstad
- Department of Pediatric Endocrinology, University of Colorado School of Medicine , Aurora, Colorado.,Barbara Davis Center for Diabetes, University of Colorado Denver , Aurora, Colorado
| | - Vesta Lai
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada
| | - Josephine Tse
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada
| | - Leslie Cham
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada
| | - Syamantak Majumder
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - Bridgit B Bowskill
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - M Golam Kabir
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - Suzanne L Advani
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - Ian W Gibson
- Department of Pathology, University of Manitoba , Winnipeg, Manitoba , Canada
| | - Manish M Sood
- Ottawa Hospital Research Institute, University of Ottawa , Ottawa, Ontario , Canada
| | - Andrew Advani
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - David Z I Cherney
- Department of Medicine, Division of Nephrology, University Health Network, University of Toronto , Toronto, Ontario , Canada.,Department of Physiology, University of Toronto , Toronto, Ontario , Canada
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190
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Steiner RW. Invited response to "Hyperfiltration After Donation and Living Kidney Donor Risk". Am J Transplant 2017; 17:2992. [PMID: 28742953 DOI: 10.1111/ajt.14445] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- R W Steiner
- Department of Nephrology, University of California Medical Center San Diego, San Diego, CA, USA
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191
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Isobe S, Ohashi N, Katahashi N, Ishigaki S, Tsuji N, Tsuji T, Kato A, Fujigaki Y, Shimizu A, Yasuda H. Focal segmental glomerulosclerosis associated with cutaneous and systemic plasmacytosis. CEN Case Rep 2017; 6:206-209. [PMID: 28939949 DOI: 10.1007/s13730-017-0276-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 09/14/2017] [Indexed: 12/28/2022] Open
Abstract
Cutaneous and systemic plasmacytosis (CSP) is a rare lymphoproliferative disorder that mainly affects middle-aged Asian individuals. Although Castleman disease is often complicated with various renal involvements, glomerulonephritis associated with CSP, which is considered as a variant of Castleman disease, is rare. This report presents the case of a 41-year-old Japanese man with nephrotic syndrome associated with CSP. Renal biopsy findings showed focal segmental glomerulosclerosis (FSGS) and diffusely mild segmental mesangial proliferation. Plasma cell infiltration in the interstitium was not observed. Electron microscopic findings showed diffuse foot process effacement, localized involvement of subendothelial space widening with amorphous materials, and endothelial cell swelling. Lymph node biopsy findings denied Castleman disease. His skin regions and proteinuria were successfully treated with prednisolone and cyclosporine. The causal relationship between CSP and FSGS is unknown. However, increased serum levels of IL-6 and VEGF and decreased VEGF expression in the podocyte may contribute to renal lesions in patients with CSP. To our best knowledge, this is the first case of a patient with FSGS associated with CSP.
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Affiliation(s)
- Shinsuke Isobe
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan.
| | - Naro Ohashi
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Naoko Katahashi
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Sayaka Ishigaki
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Naoko Tsuji
- Blood Purification Unit, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Takayuki Tsuji
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Akihiko Kato
- Blood Purification Unit, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Yoshihide Fujigaki
- Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan
| | - Akira Shimizu
- Department of Pathology, Nihon University School of Medicine, Tokyo, Japan
| | - Hideo Yasuda
- Internal Medicine 1, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
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192
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Chen X, Qin Y, Zhou T, Jiang L, Lei F, Qin H, Zhang L, Zhou Z. The potential role of retinoic acid receptor α on glomerulosclerosis in rats and podocytes injury is associated with the induction of MMP2 and MMP9. Acta Biochim Biophys Sin (Shanghai) 2017; 49:669-679. [PMID: 28645189 DOI: 10.1093/abbs/gmx066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Indexed: 02/05/2023] Open
Abstract
Retinoic acid receptor α (RARα) plays a crucial role in kidney disease. However, the underlying mechanisms in glomerulosclerosis (GS) is still not clear. The roles of RARα in an adriamycin (ADR)-induced GS rat model and in ADR-induced podocyte injury in vitro were investigated. RARα was over-expressed in GS rats, and serum, urine and kidney samples were collected to detect the induction of the expression of the receptor. RARα expression was inhibited and/or over-expressed in cultured podocytes following injury, as demonstrated by morphometric assays, cell toxicity, and matrix metalloproteinase (MMP) enzymatic activity. RARα displayed a renoprotective role in GS rats, resulting in a lower GS index, podocyte foot process fusion, and proteinuria, reduced serum creatinine and blood urea nitrogen. Further experiments indicated that RARα inhibited the accumulation of TGF-β1, α-smooth muscle actin, collagen IV, and fibronectin, while it induced MMP2 and MMP9 excessive expression in podocytes in vitro. RARα improved the renal function and attenuated the progression of GS that was associated with the over-expression of MMP2 and MMP9.
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Affiliation(s)
- Xiuping Chen
- Department of Pediatrics Nephrology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Yuanhan Qin
- Department of Pediatrics Nephrology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Tianbiao Zhou
- Department of Nephrology, the Second Affiliated Hospital of Shantou University Medical College, Shantou 515041, China
| | - Ling Jiang
- Department of Pediatrics Nephrology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Fengying Lei
- Department of Pediatrics Nephrology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - He Qin
- Department of Pediatrics Nephrology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Lei Zhang
- Department of Pediatrics Nephrology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Zhiqiang Zhou
- Department of Pediatrics Nephrology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
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193
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194
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Attini R, Leone F, Montersino B, Fassio F, Minelli F, Colla L, Rossetti M, Rollino C, Alemanno MG, Barreca A, Todros T, Piccoli GB. Pregnancy, Proteinuria, Plant-Based Supplemented Diets and Focal Segmental Glomerulosclerosis: A Report on Three Cases and Critical Appraisal of the Literature. Nutrients 2017; 9:E770. [PMID: 28753930 PMCID: PMC5537884 DOI: 10.3390/nu9070770] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Revised: 07/06/2017] [Accepted: 07/10/2017] [Indexed: 11/16/2022] Open
Abstract
Chronic kidney disease (CKD) is increasingly recognized in pregnant patients. Three characteristics are associated with a risk of preterm delivery or small for gestational age babies; kidney function reduction, hypertension, and proteinuria. In pregnancy, the anti-proteinuric agents (ACE-angiotensin converting enzyme-inhibitors or ARBS -angiotensin receptor blockers) have to be discontinued for their potential teratogenicity, and there is no validated approach to control proteinuria. Furthermore, proteinuria usually increases as an effect of therapeutic changes and pregnancy-induced hyperfiltration. Based on a favourable effect of low-protein diets on proteinuria and advanced CKD, our group developed a moderately protein-restricted vegan-vegetarian diet tsupplemented with ketoacids and aminoacids for pregnant patients. This report describes the results obtained in three pregnant patients with normal renal function, nephrotic or sub-nephrotic proteinuria, and biopsy proven diagnosis of focal segmental glomerulosclerosis, a renal lesion in which hyperfiltration is considered of pivotal importance (case 1: GFR (glomerular filtration rate): 103 mL/min; proteinuria 2.1 g/day; albumin 3.2 g/dL; case 2: GFR 86 mL/min, proteinuria 3.03 g/day, albumin 3.4 g/dL; case 3: GFR 142 mL/min, proteinuria 6.3 g/day, albumin 3.23 g/dL). The moderately restricted diet allowed a stabilisation of proteinuria in two cases and a decrease in one. No significant changes in serum creatinine and serum albumin were observed. The three babies were born at term (38 weeks + 3 days, female, weight 3180 g-62th centile; 38 weeks + 2 days, female, weight 3300 g-75th centile; male, 38 weeks + 1 day; 2770 g-8th centile), thus reassuring us of the safety of the diet. In summary, based on these three cases studies and a review of the literature, we suggest that a moderately protein-restricted, supplemented, plant-based diet might contribute to controlling proteinuria in pregnant CKD women with focal segmental glomerulosclerosis. However further studies are warranted to confirm the potential value of such a treatment strategy.
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Affiliation(s)
- Rossella Attini
- Materno-Foetal Unit, Department of Surgery, University of Torino, 10100 Turin, Italy.
| | - Filomena Leone
- Materno-Foetal Unit, Department of Surgery, University of Torino, 10100 Turin, Italy.
| | - Benedetta Montersino
- Materno-Foetal Unit, Department of Surgery, University of Torino, 10100 Turin, Italy.
| | - Federica Fassio
- Materno-Foetal Unit, Department of Surgery, University of Torino, 10100 Turin, Italy.
| | - Fosca Minelli
- Materno-Foetal Unit, Department of Surgery, University of Torino, 10100 Turin, Italy.
| | - Loredana Colla
- SCDU Nephrology, Città della Salute e della Scienza, University of Torino, 10100 Turin, Italy.
| | - Maura Rossetti
- SCDU Nephrology, Città della Salute e della Scienza, University of Torino, 10100 Turin, Italy.
| | - Cristiana Rollino
- SCDU Nephrology, Giovanni Bosco Hospital, University of Torino, 10100 Turin, Italy.
| | - Maria Grazia Alemanno
- Materno-Foetal Unit, Department of Surgery, University of Torino, 10100 Turin, Italy.
| | - Antonella Barreca
- Department of Medical Sciences, University of Torino, 10100 Turin, Italy.
| | - Tullia Todros
- Materno-Foetal Unit, Department of Surgery, University of Torino, 10100 Turin, Italy.
| | - Giorgina Barbara Piccoli
- Department of Biological and Clinical Sciences, University of Torino, 10100 Turin, Italy.
- Nephrology, Centre Hospitalier Le Mans, 72000 Le Mans, France.
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195
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Nagata M, Kobayashi N, Hara S. Focal segmental glomerulosclerosis; why does it occur segmentally? Pflugers Arch 2017; 469:983-988. [PMID: 28664408 DOI: 10.1007/s00424-017-2023-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 06/17/2017] [Accepted: 06/19/2017] [Indexed: 12/12/2022]
Abstract
Podocyte loss is the fundamental basis of glomerulosclerosis. Focal segmental glomerulosclerosis (FSGS) is a progressive glomerular disease, and its glomerular features are a prototype of podocyte loss-driven glomerulosclerosis. The glomerular pathology of FSGS is characterized by a focal and segmental location of the sclerotic lesions in human FSGS; segmental sclerosis often shows simultaneous intra- and extra-capillary changes, including parietal cell migration, capillary collapse, hyaline deposition, and intra-capillary thrombi and occasional hypercellularity. This suggests that local cellular events, initiated by podocyte loss, are the basis of the segmental lesions in FSGS. Using podocyte-specific injury by toxin administration, a series of recent works has identified the cellular basis of the glomerular response to podocyte loss. This review discusses the molecular pathway of the local response to podocyte loss and its progression to sclerosis. Recent results suggest that segmental sclerosis is a physiological tissue response aimed at halting protein leakage from a disrupted filtration barrier.
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Affiliation(s)
- Michio Nagata
- Kidney and Vascular Pathology, Faculty of Medicine, University of Tsukuba, Ten-nodai 1-1-1, Tsukuba-City, Ibaraki, 305-8577, Japan.
| | - Namiko Kobayashi
- Nephrology, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo, 113-850, Japan
| | - Satoshi Hara
- Rheumatology, Kanazawa University Graduate School of Medicine, Takara-machi 13-1, Kanazawa, Ishikawa, 920-8671, Japan
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196
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Abstract
The role of complement (C) in the pathogenesis or progression of focal segmental glomerulosclerosis (FSGS) is uncertain. The present study assessed the relationship between serum C3, the baseline characteristics, and the progression of FSGS in the cohort and identified the clinical implications of serum C3 levels in patients with FSGS. Compared to the patients with C3 ≥ 85 mg/dL (N = 474), those with C3 < 85 mg/dL (N = 117) presented a higher level of serum creatinine, lower levels of eGFR, hemoglobin, proteinuria, triglyceride, cholesterol, IgA, as well as, severe tubulointerstitial injury (TI). Of the 221 patients with a mean follow-up of 53.3 months, the risk of reaching end-stage renal disease (ESRD) was significantly higher in patients with low serum C3 level (p < 0.001). An additional 40 patients with primary FSGS revealed a significant correlation between MAC and AP (p = 0.003), MAC and serum C3 (p = 0.018), and AP and serum C3 (p = 0.028). Compared to patients with none-to-mild TI, those with moderate-to-severe TI exhibited a lower level of serum C3 and AP, and a higher level of serum MAC. In conclusion, complement activation occurring in patients with FSGS is associated with clinical and histological severities. Low serum C3 was an independent risk factor for poor renal outcome in patients with FSGS.
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197
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Abstract
Most genetic disorders are clinically and genetically heterogeneous. Next-generation sequencing (NGS) has revolutionized the field and is providing rapidly growing insights into the pathomechanism of hereditary nephropathies. Current best-practice guidelines for most hereditary nephropathies include genetic diagnostics. The increasing number of genes that have to be considered in patients with hereditary nephropathies is often challenging when addressed by conventional techniques and largely benefits from NGS-based approaches that allow the parallel analysis of all disease genes in a single test at relatively low cost, e.g., by the use of multi-gene panels. Knowledge of the underlying genotype is of advantage in discussions with regard to transplantation and therapeutic options. Further, genetics may aid the early detection and treatment of renal and extrarenal complications and the reduction of invasive procedures. An accurate genetic diagnosis is crucial for genetic counselling, provides information about the recurrence risk and may help to improve the clinical management of patients and their families. The bottleneck in genetics is no longer the primary wet lab process but the interpretation of the obtained genetic data, which is by far the most challenging and work-intensive part of the analysis. This can only be managed in a multidisciplinary setting that brings together expert knowledge in genetics and the respective medical field. In the future, bench and bedside benefits can be expected from this kind of digitized medicine.
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Rituximab for Recurrence of Primary Focal Segmental Glomerulosclerosis After Kidney Transplantation: Clinical Outcomes. Transplantation 2017; 101:649-656. [PMID: 27043407 DOI: 10.1097/tp.0000000000001160] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Rituximab has shown encouraging results for the treatment of kidney transplantation recipients with focal segmental glomerulosclerosis (FSGS) recurrence. However, the correct, opportune, and safe use of rituximab for this indication remains to be determined. METHODS This multicenter retrospective study reports on 19 new cases aged 35 (15-66) years who developed FSGS recurrence at 12 (1.5-27) days posttransplantation. Initial treatment consisted of plasma exchanges (PE), high doses of calcineurin inhibitors, and steroids. Rituximab was introduced either immediately (N = 6) or after failure of the initial treatment (N = 10) or failed attempted weaning from PE (N = 3). RESULTS Overall, we observed 9 of 19 complete remissions and 3 of 19 partial remissions. Estimated glomerular filtration rates (Modification of Diet in Renal Disease 4) were significantly higher in the responding patients than in nonresponding patients at month (M)12, M36, and M60. Overall, kidney survival at 5 years was 77.4% (95% range, 41.9-92.7). The 5-year graft survival rates in the responding patients and the nonresponding patients were 100% and 36.5%, respectively (P = 0.01). A further course of rituximab was required for 4 patients as a result of FSGS relapse, with good results. During the first year after renal transplantation, 14 patients developed severe infections (16 bacterial, 4 viral, 1 parasitic). CONCLUSIONS In kidney transplantation recipients with recurrent FSGS, rituximab therapy may be a recommended treatment for cases that have failed either the initial treatment or weaning from PE.
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Recent Treatment Advances and New Trials in Adult Nephrotic Syndrome. BIOMED RESEARCH INTERNATIONAL 2017; 2017:7689254. [PMID: 28553650 PMCID: PMC5434278 DOI: 10.1155/2017/7689254] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 04/12/2017] [Indexed: 12/13/2022]
Abstract
The etiology of nephrotic syndrome is complex and ranges from primary glomerulonephritis to secondary forms. Patients with nephrotic syndrome often need immunosuppressive treatment with its side effects and may progress to end stage renal disease. This review focuses on recent advances in the treatment of primary causes of nephrotic syndrome (idiopathic membranous nephropathy (iMN), minimal change disease (MCD), and focal segmental glomerulosclerosis (FSGS)) since the publication of the KDIGO guidelines in 2012. Current treatment recommendations are mostly based on randomized controlled trials (RCTs) in children, small RCTs, or case series in adults. Recently, only a few new RCTs have been published, such as the Gemritux trial evaluating rituximab treatment versus supportive antiproteinuric and antihypertensive therapy in iMN. Many RCTs are ongoing for iMN, MCD, and FSGS that will provide further information on the effectiveness of different treatment options for the causative disease. In addition to reviewing recent clinical studies, we provide insight into potential new targets for the treatment of nephrotic syndrome from recent basic science publications.
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Gallon L, Quaggin SE. Glomerular disease: A suPAR kidney connection found in the bone marrow. Nat Rev Nephrol 2017; 13:263-264. [PMID: 28287111 DOI: 10.1038/nrneph.2017.29] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Lorenzo Gallon
- Northwestern University Feinberg School of Medicine, Division of Nephrology &Hypertension, 303 E. Superior St., Chicago, Illinois 60611, USA
| | - Susan E Quaggin
- Northwestern University Feinberg School of Medicine, Division of Nephrology &Hypertension, 303 E. Superior St., Chicago, Illinois 60611, USA
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