1
|
Fan JH, Li XM. Mesangial cell-derived CircRNAs in chronic glomerulonephritis: RNA sequencing and bioinformatics analysis. Ren Fail 2024; 46:2371059. [PMID: 38946402 DOI: 10.1080/0886022x.2024.2371059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 06/17/2024] [Indexed: 07/02/2024] Open
Abstract
BACKGROUND Circular RNAs (circRNAs) have been shown to play critical roles in the initiation and progression of chronic glomerulonephritis (CGN), while their role from mesangial cells in contributing to the pathogenesis of CGN is rarely understood. Our study aims to explore the potential functions of mesangial cell-derived circRNAs using RNA sequencing (RNA-seq) and bioinformatics analysis. METHODS Mouse mesangial cells (MMCs) were stimulated by lipopolysaccharide (LPS) to establish an in vitro model of CGN. Pro-inflammatory cytokines and cell cycle stages were detected by Enzyme-linked immunosorbent assay (ELISA) and Flow Cytometry experiment, respectively. Subsequently, differentially expressed circRNAs (DE-circRNAs) were identified by RNA-seq. GEO microarrays were used to identify differentially expressed mRNAs (DE-mRNAs) between CGN and healthy populations. Weighted co-expression network analysis (WGCNA) was utilized to explore clinically significant modules of CGN. CircRNA-associated CeRNA networks were constructed by bioinformatics analysis. The hub mRNAs from CeRNA network were identified using LASSO algorithms. Furthermore, utilizing protein-protein interaction (PPI), gene ontology (GO), pathway enrichment (KEGG), and GSEA analyses to explore the potential biological function of target genes from CeRNA network. In addition, we investigated the relationships between immune cells and hub mRNAs from CeRNA network using CIBERSORT. RESULTS The expression of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α was drastically increased in LPS-induced MMCs. The number of cells decreased significantly in the G1 phase but increased significantly in the S/G2 phase. A total of 6 DE-mRNAs were determined by RNA-seq, including 4 up-regulated circRNAs and 2 down-regulated circRNAs. WGCNA analysis identified 1747 DE-mRNAs of the turquoise module from CGN people in the GEO database. Then, the CeRNA networks, including 6 circRNAs, 38 miRNAs, and 80 mRNAs, were successfully constructed. The results of GO and KEGG analyses revealed that the target mRNAs were mainly enriched in immune, infection, and inflammation-related pathways. Furthermore, three hub mRNAs (BOC, MLST8, and HMGCS2) from the CeRNA network were screened using LASSO algorithms. GSEA analysis revealed that hub mRNAs were implicated in a great deal of immune system responses and inflammatory pathways, including IL-5 production, MAPK signaling pathway, and JAK-STAT signaling pathway. Moreover, according to an evaluation of immune infiltration, hub mRNAs have statistical correlations with neutrophils, plasma cells, monocytes, and follicular helper T cells. CONCLUSIONS Our findings provide fundamental and novel insights for further investigations into the role of mesangial cell-derived circRNAs in CGN pathogenesis.
Collapse
Affiliation(s)
- Ji Hui Fan
- Department of Nephrology, Huaibei People's Hospital, Huaibei, China
| | - Xiao Min Li
- Department of Nephrology, Huaibei People's Hospital, Huaibei, China
- Department of Traditional Chinese Medicine, Huaibei People's Hospital, Huaibei, China
| |
Collapse
|
2
|
Oda K, Katayama K, Zang L, Toda M, Tanoue A, Saiki R, Yasuma T, D’Alessandro-Gabazza CN, Shimada Y, Mori M, Suzuki Y, Murata T, Hirai T, Tryggvason K, Gabazza EC, Dohi K. The Protective Role of KANK1 in Podocyte Injury. Int J Mol Sci 2024; 25:5808. [PMID: 38891998 PMCID: PMC11172089 DOI: 10.3390/ijms25115808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/21/2024] [Accepted: 05/25/2024] [Indexed: 06/21/2024] Open
Abstract
Approximately 30% of steroid-resistant nephrotic syndromes are attributed to monogenic disorders that involve 27 genes. Mutations in KANK family members have also been linked to nephrotic syndrome; however, the precise mechanism remains elusive. To investigate this, podocyte-specific Kank1 knockout mice were generated to examine phenotypic changes. In the initial assessment under normal conditions, Kank1 knockout mice showed no significant differences in the urinary albumin-creatinine ratio, blood urea nitrogen, serum creatinine levels, or histological features compared to controls. However, following kidney injury with adriamycin, podocyte-specific Kank1 knockout mice exhibited a significantly higher albumin-creatinine ratio and a significantly greater sclerotic index than control mice. Electron microscopy revealed more extensive foot process effacement in the knockout mice than in control mice. In addition, KANK1-deficient human podocytes showed increased detachment and apoptosis following adriamycin exposure. These findings suggest that KANK1 may play a protective role in mitigating podocyte damage under pathological conditions.
Collapse
Affiliation(s)
- Keiko Oda
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (K.O.); (A.T.); (R.S.); (M.M.); (Y.S.); (T.M.); (K.D.)
| | - Kan Katayama
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (K.O.); (A.T.); (R.S.); (M.M.); (Y.S.); (T.M.); (K.D.)
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 171 77 Stockholm, Sweden;
| | - Liqing Zang
- Graduate School of Regional Innovation Studies, Mie University, Tsu 514-8507, Mie, Japan;
| | - Masaaki Toda
- Department of Immunology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (M.T.); (T.Y.); (C.N.D.-G.); (E.C.G.)
| | - Akiko Tanoue
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (K.O.); (A.T.); (R.S.); (M.M.); (Y.S.); (T.M.); (K.D.)
| | - Ryosuke Saiki
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (K.O.); (A.T.); (R.S.); (M.M.); (Y.S.); (T.M.); (K.D.)
| | - Taro Yasuma
- Department of Immunology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (M.T.); (T.Y.); (C.N.D.-G.); (E.C.G.)
| | - Corina N. D’Alessandro-Gabazza
- Department of Immunology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (M.T.); (T.Y.); (C.N.D.-G.); (E.C.G.)
| | - Yasuhito Shimada
- Department of Integrative Pharmacology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan;
| | - Mutsuki Mori
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (K.O.); (A.T.); (R.S.); (M.M.); (Y.S.); (T.M.); (K.D.)
| | - Yasuo Suzuki
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (K.O.); (A.T.); (R.S.); (M.M.); (Y.S.); (T.M.); (K.D.)
| | - Tomohiro Murata
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (K.O.); (A.T.); (R.S.); (M.M.); (Y.S.); (T.M.); (K.D.)
| | - Toshinori Hirai
- Department of Pharmacy, Faculty of Medicine, Mie University Hospital, Tsu 514-8507, Mie, Japan;
| | - Karl Tryggvason
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 171 77 Stockholm, Sweden;
| | - Esteban C. Gabazza
- Department of Immunology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (M.T.); (T.Y.); (C.N.D.-G.); (E.C.G.)
| | - Kaoru Dohi
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Mie, Japan; (K.O.); (A.T.); (R.S.); (M.M.); (Y.S.); (T.M.); (K.D.)
| |
Collapse
|
3
|
Skitchenko R, Modrusan Z, Loboda A, Kopp JB, Winkler CA, Sergushichev A, Gupta N, Stevens C, Daly MJ, Shaw A, Artomov M. CR1 variants contribute to FSGS susceptibility across multiple populations. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.11.20.23298462. [PMID: 38076851 PMCID: PMC10705641 DOI: 10.1101/2023.11.20.23298462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS) is a common cause of nephrotic syndrome with an annual incidence in the United States in African-Americans compared to European-Americans of 24 cases and 5 cases per million, respectively. Among glomerular diseases in Europe and Latin-America, FSGS was the second most frequent diagnosis, and in Asia the fifth. We expand previous efforts in understanding genetics of FSGS by performing a case-control study involving ethnically-diverse groups FSGS cases (726) and a pool of controls (13,994), using panel sequencing of approximately 2,500 podocyte-expressed genes. Through rare variant association tests, we replicated known risk genes - KANK1, COL4A4, and APOL1. A novel significant association was observed for the gene encoding complement receptor 1 (CR1). High-risk rare variants in CR1 in the European-American cohort were commonly observed in Latin- and African-Americans. Therefore, a combined rare and common variant analysis was used to replicate the CR1 association in non-European populations. The CR1 risk variant, rs17047661, gives rise to the Sl1/Sl2 (R1601G) allele that was previously associated with protection against cerebral malaria. Pleiotropic effects of rs17047661 may explain the difference in allele frequencies across continental ancestries and suggest a possible role for genetically-driven alterations of adaptive immunity in the pathogenesis of FSGS.
Collapse
Affiliation(s)
- Rostislav Skitchenko
- ITMO University, St. Petersburg, Russia
- Almazov National Medical Research Centre, St. Petersburg, Russia
| | - Zora Modrusan
- Research Biology, Genentech Inc., San Francisco, CA, USA
| | - Alexander Loboda
- ITMO University, St. Petersburg, Russia
- Almazov National Medical Research Centre, St. Petersburg, Russia
- Broad Institute, Cambridge, MA, USA
| | - Jeffrey B. Kopp
- Kidney Disease Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Cheryl A. Winkler
- Molecular Genetic Epidemiology Studies Section, National Cancer Institute (NCI), Frederick, Maryland, USA
| | | | | | | | - Mark J. Daly
- Broad Institute, Cambridge, MA, USA
- Massachusetts General Hospital, Boston, MA, USA
- Institute for Molecular Medicine Finland, Helsinki, Finland
| | - Andrey Shaw
- Research Biology, Genentech Inc., San Francisco, CA, USA
| | - Mykyta Artomov
- Broad Institute, Cambridge, MA, USA
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| |
Collapse
|
4
|
Marcos González S, Rodrigo Calabia E, Varela I, Červienka M, Freire Salinas J, Gómez Román JJ. High Rate of Mutations of Adhesion Molecules and Extracellular Matrix Glycoproteins in Patients with Adult-Onset Focal and Segmental Glomerulosclerosis. Biomedicines 2023; 11:1764. [PMID: 37371859 DOI: 10.3390/biomedicines11061764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/15/2023] [Accepted: 06/18/2023] [Indexed: 06/29/2023] Open
Abstract
(1) Background: Focal and segmental glomerulosclerosis (FSGS) is a pattern of injury that results from podocyte loss in the setting of a wide variety of injurious mechanisms. These include both acquired and genetic as well as primary and secondary causes, or a combination thereof, without optimal therapy, and a high rate of patients develop end-stage renal disease (ESRD). Genetic studies have helped improve the global understanding of FSGS syndrome; thus, we hypothesize that patients with primary FSGS may have underlying alterations in adhesion molecules or extracellular matrix glycoproteins related to previously unreported mutations that may be studied through next-generation sequencing (NGS). (2) Methods: We developed an NGS panel with 29 genes related to adhesion and extracellular matrix glycoproteins. DNA was extracted from twenty-three FSGS patients diagnosed by renal biopsy; (3) Results: The average number of accumulated variants in FSGS patients was high. We describe the missense variant ITGB3c.1199G>A, which is considered pathogenic; in addition, we discovered the nonsense variant CDH1c.499G>T, which lacks a Reference SNP (rs) Report and is considered likely pathogenic. (4) Conclusions: To the best of our knowledge, this is the first account of a high rate of change in extracellular matrix glycoproteins and adhesion molecules in individuals with adult-onset FSGS. The combined effect of all these variations may result in a genotype that is vulnerable to the pathogenesis of glomerulopathy.
Collapse
Affiliation(s)
- Sara Marcos González
- Pathology Department, Marqués de Valdecilla University Hospital, Institute of Research Valdecilla (IDIVAL), 39008 Santander, Spain
| | - Emilio Rodrigo Calabia
- Nephrology Department, Marqués de Valdecilla University Hospital, 39008, University of Cantabria, 39005 Santander, Spain
| | - Ignacio Varela
- Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), 39011, University of Cantabria-CSIC, 39005 Santander, Spain
| | - Michal Červienka
- Nephrology Department, Rio Carrion General Hospital, 34005 Palencia, Spain
| | - Javier Freire Salinas
- Anatomic Pathology, Marqués de Valdecilla University Hospital, Institute of Research Valdecilla (IDIVAL), 39008 Santander, Spain
| | - José Javier Gómez Román
- Pathology Department, Marqués de Valdecilla University Hospital, Institute of Research Valdecilla (IDIVAL), School of Medicine, University of Cantabria, 39008 Santander, Spain
| |
Collapse
|
5
|
Nandlal L, Winkler CA, Bhimma R, Cho S, Nelson GW, Haripershad S, Naicker T. Causal and putative pathogenic mutations identified in 39% of children with primary steroid-resistant nephrotic syndrome in South Africa. Eur J Pediatr 2022; 181:3595-3606. [PMID: 35920919 PMCID: PMC10673688 DOI: 10.1007/s00431-022-04581-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 07/26/2022] [Accepted: 07/26/2022] [Indexed: 11/03/2022]
Abstract
There is a paucity of data identifying genetic mutations that account for the high rate of steroid-resistant nephrotic syndrome (SRNS) in a South African paediatric population. The aim was to identify causal mutations in genes implicated in SRNS within a South African paediatric population. We enrolled 118 children with primary nephrotic syndrome (NS), 70 SRNS and 48 steroid-sensitive NS. All children with SRNS underwent kidney biopsy. We first genotyped the NPHS2 gene for the p.V260E variant in all NS cases (n = 118) and controls (n = 219). To further identify additional variants, we performed whole-exome sequencing and interrogated ten genes (NPHS1, NPHS2, WT1, LAMB2, ACTN4, TRPC6, INF2, CD2AP, PLCE1, MYO1E) implicated in SRNS with histopathological features of focal segmental glomerulosclerosis (FSGS) in 56 SRNS cases and 29 controls; we also performed exome sequencing on two patients carrying the NPHS2 p.V260E mutation as positive controls. The overall detection rate of causal and putative pathogenic mutations in children with SRNS was 27/70 (39%): 15 (21%) carried the NPHS2 p.V260E causal mutation in the homozygous state, and 12 (17%) SRNS cases carried a putative pathogenic mutation in the heterozygous state in genes (INF2 (n = 8), CD2AP (n = 3) and TRPC6 (n = 1)) known to have autosomal dominant inheritance mode. NPHS2 p.V260E homozygosity was specifically associated with biopsy-proven FSGS, accounting for 24% of children of Black ethnicity (15 of 63) with steroid-resistant FSGS. No causal or putative pathogenic mutations were identified in NPHS1, WT1, LAMB2, PLCE1, MYO1E and ACTN4. We report four novel variants in INF2, PLCE1, ACTN4 and TRPC6. Conclusion: We report putative missense variants predicted to be pathogenic in INF2, CD2AP and TRPC6 among steroid-resistant-FSGS children. However, the NPHS2 p.V260E mutation is a prevalent cause of steroid-resistant FSGS among Black South African children occurring in 24% of children with SRNS. Screening all Black African children presenting with NS for NPHS2 p.V260E will provide a precision diagnosis of steroid-resistant FSGS and inform clinical management. What is Known: • Limited data is available on the genetic disparity of SNRS in a South African paediatric setting. • The high rate of steroid resistance in Black South African children with FSGS compared to other racial groups is partially explained by the founder variant NPHS2 p.V260E. What is New: • We report putative missense variants predicted to be pathogenic in INF2, CD2AP and TRPC6 among steroid-resistant FSGS children. • NPHS2 p.V260E mutation remains a prevalent cause of steroid-resistant FSGS among Black South African children, demonstrating precision diagnostic utility.
Collapse
Affiliation(s)
- Louansha Nandlal
- Discipline of Optics and Imaging, University of KwaZulu-Natal, Durban, South Africa.
| | - Cheryl A Winkler
- Basic Research Program, Molecular Genetics Epidemiology Section, Frederick National Laboratory of the National Cancer Institute, Washington, DC, USA
| | - Rajendra Bhimma
- Department of Paediatrics and Child Health, University of KwaZulu-Natal, Durban, South Africa
| | - Sungkweon Cho
- Basic Research Program, Molecular Genetics Epidemiology Section, Frederick National Laboratory of the National Cancer Institute, Washington, DC, USA
| | - George W Nelson
- Frederick National Laboratory for Cancer Research, Frederick Advanced Biomedical Computational Science, Washington, DC, USA
| | - Sudesh Haripershad
- Department of Nephrology, University of KwaZulu-Natal, Durban, South Africa
| | - Thajasvarie Naicker
- Discipline of Optics and Imaging, University of KwaZulu-Natal, Durban, South Africa
| |
Collapse
|
6
|
Jiao J, Wang L, Ni F, Wang M, Feng S, Gao X, Chan H, Yang X, Lee H, Chi H, Chen X, Wu D, Zhang G, Yang B, Wang A, Yang Q, Wan J, Yu S, Li X, Wang M, Chen X, Mai X, Ruan X, Yang H, Li Q. Whole-exome sequencing of a multicenter cohort identifies genetic changes associated with clinical phenotypes in pediatric nephrotic syndrome. Genes Dis 2022; 9:1662-1673. [PMID: 36157477 PMCID: PMC9485284 DOI: 10.1016/j.gendis.2022.03.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 03/06/2022] [Accepted: 03/22/2022] [Indexed: 11/19/2022] Open
Abstract
Understanding the association between the genetic and clinical phenotypes in children with nephrotic syndrome (NS) of different etiologies is critical for early clinical guidance. We employed whole-exome sequencing (WES) to detect monogenic causes of NS in a multicenter cohort of 637 patients. In this study, a genetic cause was identified in 30.0% of the idiopathic steroid-resistant nephrotic syndrome (SRNS) patients. Other than congenital nephrotic syndrome (CNS), there were no significant differences in the incidence of monogenic diseases based on the age at manifestation. Causative mutations were detected in 39.5% of patients with focal segmental glomerulosclerosis (FSGS) and 9.2% of those with minimal change disease (MCD). In terms of the patterns in patients with different types of steroid resistance, a single gene mutation was identified in 34.8% of patients with primary resistance, 2.9% with secondary resistance, and 71.4% of children with multidrug resistance. Among the various intensified immunosuppressive therapies, tacrolimus (TAC) showed the highest response rate, with 49.7% of idiopathic SRNS patients achieving complete remission. Idiopathic SRNS patients with monogenic disease showed a similar multidrug resistance pattern, and only 31.4% of patients with monogenic disease achieved a partial remission on TAC. During an average 4.1-year follow-up, 21.4% of idiopathic SRNS patients with monogenic disease progressed to end-stage renal disease (ESRD). Collectively, this study provides evidence that genetic testing is necessary for presumed steroid-resistant and idiopathic SRNS patients, especially those with primary and/or multidrug resistance.
Collapse
Affiliation(s)
- Jia Jiao
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Li Wang
- Department of Nephrology, Chengdu Women and Children Central Hospital, Chengdu, Sichuan 610091, PR China
| | - Fenfen Ni
- Department of Nephrology, Sheen Children's Hospital, Shenzhen, Guangdong 518034, PR China
| | - Mo Wang
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Shipin Feng
- Department of Nephrology, Chengdu Women and Children Central Hospital, Chengdu, Sichuan 610091, PR China
| | - Xiaojie Gao
- Department of Nephrology, Sheen Children's Hospital, Shenzhen, Guangdong 518034, PR China
| | - Han Chan
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Xueying Yang
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Hao Lee
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Huan Chi
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Xuelan Chen
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Daoqi Wu
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Gaofu Zhang
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Baohui Yang
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Anshuo Wang
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Qin Yang
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Junli Wan
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Sijie Yu
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Xiaoqin Li
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Mei Wang
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Xiaofeng Chen
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Xianying Mai
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
| | - Xiongzhong Ruan
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, PR China
- John Moorhead Research Laboratory, Centre for Nephrology, University College London Medical School, Royal Free Campus, University College London, London WC1E 6BT, United Kingdom
| | - Haiping Yang
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
- Corresponding author.
| | - Qiu Li
- Department of Nephrology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400015, PR China
- Corresponding author.
| |
Collapse
|
7
|
van de Leemput J, Wen P, Han Z. Using Drosophila Nephrocytes to Understand the Formation and Maintenance of the Podocyte Slit Diaphragm. Front Cell Dev Biol 2022; 10:837828. [PMID: 35265622 PMCID: PMC8898902 DOI: 10.3389/fcell.2022.837828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/01/2022] [Indexed: 12/12/2022] Open
Abstract
The podocyte slit diaphragm (SD) is an essential component of the glomerular filtration barrier and its disruption is a common cause of proteinuria and many types of kidney disease. Therefore, better understanding of the pathways and proteins that play key roles in SD formation and maintenance has been of great interest. Podocyte and SD biology have been mainly studied using mouse and other vertebrate models. However, vertebrates are limited by inherent properties and technically challenging in vivo access to the podocytes. Drosophila is a relatively new alternative model system but it has already made great strides. Past the initial obvious differences, mammalian podocytes and fly nephrocytes are remarkably similar at the genetic, molecular and functional levels. This review discusses SD formation and maintenance, and their dependence on cell polarity, the cytoskeleton, and endo- and exocytosis, as learned from studies in fly nephrocytes and mammalian podocytes. In addition, it reflects on the remaining gaps in our knowledge, the physiological implications for glomerular diseases and how we can leverage the advantages Drosophila has to offer to further our understanding.
Collapse
Affiliation(s)
- Joyce van de Leemput
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States.,Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Pei Wen
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States.,Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Zhe Han
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States.,Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| |
Collapse
|
8
|
Sun K, Xie Q, Hao CM. Mechanisms of Scarring in Focal Segmental Glomerulosclerosis. KIDNEY DISEASES (BASEL, SWITZERLAND) 2021; 7:350-358. [PMID: 34604342 PMCID: PMC8443927 DOI: 10.1159/000517108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 04/27/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Focal segmental glomerulosclerosis (FSGS) is a histologic pattern characterized by focal glomerular scarring, which often progresses to systemic and diffuse glomerulosclerosis. Previous studies have emphasized that the initiation of classic FSGS occurs in podocytes. The dysfunction and loss of podocytes have been associated with the development of proteinuria and the progression of various diseases. In addition, primary, secondary, and genetic FSGS are caused by different mechanisms of podocyte injury. SUMMARY The potential sources and mechanism of podocyte supplementation are the focus of our current research. Increasing attention has been paid to the role played by parietal epithelial cells (PECs) during the progression of FSGS. PECs are not only the primary influencing factors in glomerulosclerosis lesions but also have repair abilities, which remain a focus of debate. Notably, other resident glomerular cells also play significant roles in the progression of this disease. KEY MESSAGE In this review, we focus on the mechanism of scarring in FSGS and discuss current and potential therapeutic strategies.
Collapse
Affiliation(s)
- Ke Sun
- Division of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Qionghong Xie
- Division of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Chuan-Ming Hao
- Division of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
- Nephrology Division, Vanderbilt University Medical Center School of Medicine, Nashville, Tennessee, USA
| |
Collapse
|
9
|
Mysh M, Poulton JS. The Basolateral Polarity Module Promotes Slit Diaphragm Formation in Drosophila Nephrocytes, a Model of Vertebrate Podocytes. J Am Soc Nephrol 2021; 32:1409-1424. [PMID: 33795424 PMCID: PMC8259641 DOI: 10.1681/asn.2020071050] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 02/12/2021] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Podocyte slit diaphragms (SDs) are intercellular junctions that function as size-selective filters, excluding most proteins from urine. Abnormalities in SDs cause proteinuria and nephrotic syndrome. Podocytes exhibit apicobasal polarity, which can affect fundamental aspects of cell biology, including morphology, intercellular junction formation, and asymmetric protein distribution along the plasma membrane. Apical polarity protein mutations cause nephrotic syndrome, and data suggest apical polarity proteins regulate SD formation. However, there is no evidence that basolateral polarity proteins regulate SDs. Thus, the role of apicobasal polarity in podocytes remains unclear. METHODS Genetic manipulations and transgenic reporters determined the effects of disrupting apicobasal polarity proteins in Drosophila nephrocytes, which have SDs similar to those of mammalian podocytes. Confocal and electron microscopy were used to characterize SD integrity after loss of basolateral polarity proteins, and genetic-interaction studies illuminated relationships among apicobasal polarity proteins. RESULTS The study identified four novel regulators of nephrocyte SDs: Dlg, Lgl, Scrib, and Par-1. These proteins comprise the basolateral polarity module and its effector kinase. The data suggest these proteins work together, with apical polarity proteins, to regulate SDs by promoting normal endocytosis and trafficking of SD proteins. CONCLUSIONS Given the recognized importance of apical polarity proteins and SD protein trafficking in podocytopathies, the findings connecting basolateral polarity proteins to these processes significantly advance our understanding of SD regulation.
Collapse
Affiliation(s)
- Michael Mysh
- Department of Biology, UNC Kidney Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - John S. Poulton
- Division of Nephrology and Hypertension, Department of Medicine, UNC Kidney Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| |
Collapse
|
10
|
Ning L, Suleiman HY, Miner JH. Synaptopodin deficiency exacerbates kidney disease in a mouse model of Alport syndrome. Am J Physiol Renal Physiol 2021; 321:F12-F25. [PMID: 34029143 DOI: 10.1152/ajprenal.00035.2021] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Synaptopodin (Synpo) is an actin-associated protein in podocyte foot processes. By generating mice that completely lack Synpo, we previously showed that Synpo is dispensable for normal kidney function. However, lack of Synpo worsened adriamycin-induced nephropathy, indicating a protective role for Synpo in injured podocytes. Here, we investigated whether lack of Synpo directly impacts a genetic disease, Alport syndrome (AS), because Synpo is reduced in podocytes of affected humans and mice; whether this is merely an association or pathogenic is unknown. We used collagen type IV-α5 (Col4a5) mutant mice, which model X-linked AS, showing glomerular basement membrane (GBM) abnormalities, eventual foot process effacement, and progression to end-stage kidney disease. We intercrossed mice carrying mutations in Synpo and Col4a5 to produce double-mutant mice. Urine and tissue were taken at select time points to evaluate albuminuria, histopathology, and glomerular capillary wall composition and ultrastructure. Lack of Synpo in Col4a5-/Y, Col4a5-/-, or Col4a5+/- Alport mice led to the acceleration of disease progression, including more severe proteinuria and glomerulosclerosis. Absence of Synpo attenuated the shift of myosin IIA from the podocyte cell body and major processes to actin cables near the GBM in the areas of effacement. We speculate that this is mechanistically associated with enhanced loss of podocytes due to easier detachment from the GBM. We conclude that Synpo deletion exacerbates the disease phenotype in Alport mice, revealing the podocyte actin cytoskeleton as a target for therapy in patients with AS.NEW & NOTEWORTHY Alport syndrome (AS) is a hereditary disease of the glomerular basement with hematuria and proteinuria. Podocytes eventually exhibit foot process effacement, indicating actin cytoskeletal changes. To investigate how cytoskeletal changes impact podocytes, we generated Alport mice lacking synaptopodin, an actin-binding protein in foot processes. Analysis showed a more rapid disease progression, demonstrating that synaptopodin is protective. This suggests that the actin cytoskeleton is a target for therapy in AS and perhaps other glomerular diseases.
Collapse
Affiliation(s)
- Liang Ning
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
11
|
Sidhom EH, Kim C, Kost-Alimova M, Ting MT, Keller K, Avila-Pacheco J, Watts AJ, Vernon KA, Marshall JL, Reyes-Bricio E, Racette M, Wieder N, Kleiner G, Grinkevich EJ, Chen F, Weins A, Clish CB, Shaw JL, Quinzii CM, Greka A. Targeting a Braf/Mapk pathway rescues podocyte lipid peroxidation in CoQ-deficiency kidney disease. J Clin Invest 2021; 131:141380. [PMID: 33444290 DOI: 10.1172/jci141380] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 01/06/2021] [Indexed: 12/19/2022] Open
Abstract
Mutations affecting mitochondrial coenzyme Q (CoQ) biosynthesis lead to kidney failure due to selective loss of podocytes, essential cells of the kidney filter. Curiously, neighboring tubular epithelial cells are spared early in disease despite higher mitochondrial content. We sought to illuminate noncanonical, cell-specific roles for CoQ, independently of the electron transport chain (ETC). Here, we demonstrate that CoQ depletion caused by Pdss2 enzyme deficiency in podocytes results in perturbations in polyunsaturated fatty acid (PUFA) metabolism and the Braf/Mapk pathway rather than ETC dysfunction. Single-nucleus RNA-Seq from kidneys of Pdss2kd/kd mice with nephrotic syndrome and global CoQ deficiency identified a podocyte-specific perturbation of the Braf/Mapk pathway. Treatment with GDC-0879, a Braf/Mapk-targeting compound, ameliorated kidney disease in Pdss2kd/kd mice. Mechanistic studies in Pdss2-depleted podocytes revealed a previously unknown perturbation in PUFA metabolism that was confirmed in vivo. Gpx4, an enzyme that protects against PUFA-mediated lipid peroxidation, was elevated in disease and restored after GDC-0879 treatment. We demonstrate broader human disease relevance by uncovering patterns of GPX4 and Braf/Mapk pathway gene expression in tissue from patients with kidney diseases. Our studies reveal ETC-independent roles for CoQ in podocytes and point to Braf/Mapk as a candidate pathway for the treatment of kidney diseases.
Collapse
Affiliation(s)
- Eriene-Heidi Sidhom
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Choah Kim
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | | | - May Theng Ting
- Department of Neurology, Columbia University Medical Center, New York, New York, USA
| | - Keith Keller
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | | | - Andrew Jb Watts
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Katherine A Vernon
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Jamie L Marshall
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | | | - Matthew Racette
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Nicolas Wieder
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Giulio Kleiner
- Department of Neurology, Columbia University Medical Center, New York, New York, USA
| | | | - Fei Chen
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Astrid Weins
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Clary B Clish
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Jillian L Shaw
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Catarina M Quinzii
- Department of Neurology, Columbia University Medical Center, New York, New York, USA
| | - Anna Greka
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| |
Collapse
|
12
|
Demir E, Caliskan Y. Variations of type IV collagen-encoding genes in patients with histological diagnosis of focal segmental glomerulosclerosis. Pediatr Nephrol 2020; 35:927-936. [PMID: 31254113 DOI: 10.1007/s00467-019-04282-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/01/2019] [Accepted: 05/31/2019] [Indexed: 01/07/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS), an important cause of end-stage kidney disease (ESKD), covers a spectrum of clinicopathological syndromes sharing a common glomerular lesion, based on an injury of podocytes caused by diverse insults to glomeruli. Although it is well expressed in many reports that the term FSGS is not useful and applicable to a single disease, particularly in genetic studies, FSGS continues to be used as a single clinical diagnosis. Distinguishing genetic forms of FSGS is important for the treatment and overall prognosis because secondary forms of FSGS, produced by rare pathogenic variations in podocyte genes, are not good candidates for immunosuppressive treatment. Over the past decade, several next generation sequencing (NGS) methods have been used to investigate the patients with steroid resistance nephrotic syndrome (SRNS) or FSGS. Pathogenic variants in COL4A3, COL4A4, or COL4A5 genes have been frequently identified in patients with histologic diagnosis of FSGS. The contribution of these mostly heterozygous genetic variations in FSGS pathogenesis and the clinical course of patients with these variations have not been well characterized. This review emphasizes the importance of appropriate approach in selection and diagnosis of cases and interpretation of the genetic data in these studies and suggests a detailed review of existing clinical variant databases using newly available population genetic data.
Collapse
Affiliation(s)
- Erol Demir
- Division of Nephrology, Department of Internal Medicine, Istanbul School of Medicine, Istanbul University, Capa, Fatih, 34093, Istanbul, Turkey
| | - Yasar Caliskan
- Division of Nephrology, Department of Internal Medicine, Istanbul School of Medicine, Istanbul University, Capa, Fatih, 34093, Istanbul, Turkey.
| |
Collapse
|
13
|
Rinschen MM, Gödel M, Grahammer F, Zschiedrich S, Helmstädter M, Kretz O, Zarei M, Braun DA, Dittrich S, Pahmeyer C, Schroder P, Teetzen C, Gee H, Daouk G, Pohl M, Kuhn E, Schermer B, Küttner V, Boerries M, Busch H, Schiffer M, Bergmann C, Krüger M, Hildebrandt F, Dengjel J, Benzing T, Huber TB. A Multi-layered Quantitative In Vivo Expression Atlas of the Podocyte Unravels Kidney Disease Candidate Genes. Cell Rep 2019; 23:2495-2508. [PMID: 29791858 PMCID: PMC5986710 DOI: 10.1016/j.celrep.2018.04.059] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 02/07/2018] [Accepted: 04/15/2018] [Indexed: 12/31/2022] Open
Abstract
Damage to and loss of glomerular podocytes has been identified as the culprit lesion in progressive kidney diseases. Here, we combine mass spectrometry-based proteomics with mRNA sequencing, bioinformatics, and hypothesis-driven studies to provide a comprehensive and quantitative map of mammalian podocytes that identifies unanticipated signaling pathways. Comparison of the in vivo datasets with proteomics data from podocyte cell cultures showed a limited value of available cell culture models. Moreover, in vivo stable isotope labeling by amino acids uncovered surprisingly rapid synthesis of mitochondrial proteins under steady-state conditions that was perturbed under autophagy-deficient, disease-susceptible conditions. Integration of acquired omics dimensions suggested FARP1 as a candidate essential for podocyte function, which could be substantiated by genetic analysis in humans and knockdown experiments in zebrafish. This work exemplifies how the integration of multi-omics datasets can identify a framework of cell-type-specific features relevant for organ health and disease. Deep proteome and transcriptome analyses of native podocytes unravel druggable targets Static and dynamic proteomics uncover features of podocyte identity and proteostasis Candidate genes for nephrotic syndrome were predicted based on multi-omic integration FARP1 is a previously unreported candidate gene for human proteinuric kidney disease
Collapse
Affiliation(s)
- Markus M Rinschen
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany; Systems Biology of Ageing Cologne (Sybacol), University of Cologne, 50931 Cologne, Germany.
| | - Markus Gödel
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Florian Grahammer
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Stefan Zschiedrich
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Martin Helmstädter
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Oliver Kretz
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Mostafa Zarei
- Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79104 Freiburg, Germany; Center for Systems Biology (ZBSA), Albert Ludwigs University, 79104 Freiburg, Germany
| | - Daniela A Braun
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Sebastian Dittrich
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Caroline Pahmeyer
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Patricia Schroder
- Department of Medicine/Nephrology, Hannover Medical School, 30625 Hannover, Germany; Mount Desert Island Biological Laboratory, Salisbury Cove, ME 04609, USA
| | - Carolin Teetzen
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - HeonYung Gee
- Mount Desert Island Biological Laboratory, Salisbury Cove, ME 04609, USA; Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Ghaleb Daouk
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Martin Pohl
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Medical Center and Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Elisa Kuhn
- Center for Human Genetics, Bioscientia, 55218 Ingelheim, Germany
| | - Bernhard Schermer
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany; Systems Biology of Ageing Cologne (Sybacol), University of Cologne, 50931 Cologne, Germany
| | - Victoria Küttner
- Department for Neuroanatomy, University of Freiburg, 79104 Freiburg, Germany; Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79104 Freiburg, Germany; Department of Dermatology, Medical Center - University of Freiburg, 79106 Freiburg, Germany
| | - Melanie Boerries
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert Ludwigs University Freiburg, 79106 Freiburg, Germany; German Cancer Consortium (DKTK), 79106 Freiburg, Germany; German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Hauke Busch
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, Albert Ludwigs University Freiburg, 79106 Freiburg, Germany; Lübeck Institute for Experimental Dermatology (LIED), University of Lübeck, 23562 Lübeck, Germany
| | - Mario Schiffer
- Department of Medicine/Nephrology, Hannover Medical School, 30625 Hannover, Germany; Mount Desert Island Biological Laboratory, Salisbury Cove, ME 04609, USA
| | - Carsten Bergmann
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany; Center for Human Genetics, Bioscientia, 55218 Ingelheim, Germany
| | - Marcus Krüger
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Friedhelm Hildebrandt
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Joern Dengjel
- Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79104 Freiburg, Germany; Center for Systems Biology (ZBSA), Albert Ludwigs University, 79104 Freiburg, Germany; Department of Dermatology, Medical Center - University of Freiburg, 79106 Freiburg, Germany; Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland; BIOSS Centre for Biological Signaling Studies, Albert Ludwigs University Freiburg, 79104 Freiburg, Germany
| | - Thomas Benzing
- Department II of Internal Medicine, University of Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany; Systems Biology of Ageing Cologne (Sybacol), University of Cologne, 50931 Cologne, Germany.
| | - Tobias B Huber
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany; Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, 79104 Freiburg, Germany; Center for Systems Biology (ZBSA), Albert Ludwigs University, 79104 Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, Albert Ludwigs University Freiburg, 79104 Freiburg, Germany.
| |
Collapse
|
14
|
Pablo JL, Greka A. Charting a TRP to Novel Therapeutic Destinations for Kidney Diseases. Trends Pharmacol Sci 2019; 40:911-918. [PMID: 31704171 DOI: 10.1016/j.tips.2019.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/24/2019] [Accepted: 10/07/2019] [Indexed: 12/29/2022]
Abstract
Ion channels are critical to kidney function, and their dysregulation leads to several distinct kidney diseases. Of the diversity of ion channels in kidney cells, the transient receptor potential (TRP) superfamily of proteins plays important and varied roles in both maintaining homeostasis as well as in causing disease. Recent work showed that TRPC5 blockers could successfully protect critical components of the kidney filter both in vitro and in vivo, thus revealing TRPC5 as a tractable therapeutic target for focal and segmental glomerulosclerosis (FSGS), a common cause of kidney failure. Human genetics point to three additional TRP channels as plausible therapeutic targets: TRPC6 in FSGS, PKD2 in polycystic kidney disease, and TRPM6 in familial hypomagnesemia with secondary hypocalcemia (HSH). We conclude that targeting TRP channels could pave the way for much needed therapies for kidney diseases.
Collapse
Affiliation(s)
- Juan Lorenzo Pablo
- Broad Institute of MIT and Harvard, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Anna Greka
- Broad Institute of MIT and Harvard, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
15
|
Abstract
Podocytes, or glomerular epithelial cells, form the final layer in the glomerular capillary wall of the kidney. Along with the glomerular basement membrane and glomerular endothelial cells, they make up the glomerular filtration barrier which allows the passage of water and small molecules and, in healthy individuals, prevents the passage of albumin and other key proteins. The podocyte is a specialised and terminally differentiated cell with a specific cell morphology that is largely dependent on a highly dynamic underlying cytoskeletal network and that is essential for maintaining glomerular function and integrity in healthy kidneys. The RhoGTPases (RhoA, Rac1 and Cdc42), which act as molecular switches that regulate actin dynamics, are known to play a crucial role in maintaining the cytoskeletal and molecular integrity of the podocyte foot processes in a dynamic manner. Recently, novel protein interaction networks that regulate the RhoGTPases in the podocyte and that are altered by disease have been discovered. This review will discuss these networks and their potential as novel therapeutic targets in nephrotic syndrome. It will also discuss the evidence that they are direct targets for (a) steroids, the first-line agents for the treatment of nephrotic syndrome, and (b) certain kinase inhibitors used in cancer treatment, leading to nephrotoxicity.
Collapse
Affiliation(s)
- Moin A. Saleem
- Bristol Renal, Bristol Medical School, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY, UK
| | - Gavin I. Welsh
- Bristol Renal, Bristol Medical School, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY, UK
| |
Collapse
|
16
|
Zhong J, Whitman JB, Yang HC, Fogo AB. Mechanisms of Scarring in Focal Segmental Glomerulosclerosis. J Histochem Cytochem 2019; 67:623-632. [PMID: 31116068 PMCID: PMC6713971 DOI: 10.1369/0022155419850170] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 04/22/2019] [Indexed: 01/17/2023] Open
Abstract
Focal segmental glomerulosclerosis (FSGS) presents with scar in parts of some glomeruli and often progresses to global and diffuse glomerulosclerosis. Podocyte injury is the initial target in primary FSGS, induced by a circulating factor. Several gene variants, for example, APOL1, are associated with increased susceptibility to FSGS. Primary FSGS may be due to genetic mutation in key podocyte genes. Increased work stress after loss of nephrons, epigenetic mechanisms, and various profibrotic pathways can contribute to progressive sclerosis, regardless of the initial injury. The progression of FSGS lesions also involves crosstalk between podocytes and other kidney cells, such as parietal epithelial cells, glomerular endothelial cells, and even tubular epithelial cells. New insights related to these mechanisms could potentially lead to new therapeutic strategies to prevent progression of FSGS.
Collapse
Affiliation(s)
- Jianyong Zhong
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
- Division of Pediatric Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jacob B Whitman
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Hai-Chun Yang
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
- Division of Pediatric Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Agnes B Fogo
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
- Division of Pediatric Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee
| |
Collapse
|
17
|
Schulz A, Müller NV, van de Lest NA, Eisenreich A, Schmidbauer M, Barysenka A, Purfürst B, Sporbert A, Lorenzen T, Meyer AM, Herlan L, Witten A, Rühle F, Zhou W, de Heer E, Scharpfenecker M, Panáková D, Stoll M, Kreutz R. Analysis of the genomic architecture of a complex trait locus in hypertensive rat models links Tmem63c to kidney damage. eLife 2019; 8:42068. [PMID: 30900988 PMCID: PMC6478434 DOI: 10.7554/elife.42068] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 03/20/2019] [Indexed: 12/23/2022] Open
Abstract
Unraveling the genetic susceptibility of complex diseases such as chronic kidney disease remains challenging. Here, we used inbred rat models of kidney damage associated with elevated blood pressure for the comprehensive analysis of a major albuminuria susceptibility locus detected in these models. We characterized its genomic architecture by congenic substitution mapping, targeted next-generation sequencing, and compartment-specific RNA sequencing analysis in isolated glomeruli. This led to prioritization of transmembrane protein Tmem63c as a novel potential target. Tmem63c is differentially expressed in glomeruli of allele-specific rat models during onset of albuminuria. Patients with focal segmental glomerulosclerosis exhibited specific TMEM63C loss in podocytes. Functional analysis in zebrafish revealed a role for tmem63c in mediating the glomerular filtration barrier function. Our data demonstrate that integrative analysis of the genomic architecture of a complex trait locus is a powerful tool for identification of new targets such as Tmem63c for further translational investigation. The human kidneys filter the entire volume of the blood about 300 times each day. This ability depends on specialized cells, known as podocytes, which wrap around some of the blood vessels in the kidney. These cells control which molecules leave the blood based on their size. Normally large molecules like proteins are blocked, while smaller molecules including waste products, toxins, excess water and salts pass through into the urine. If this filtration system is damaged, by high blood pressure, for example, it can lead to chronic kidney disease. A hallmark of this disease, often called CKD for short, is high levels of the protein albumin in the urine. Previous studies involving rats with high blood pressure have found several regions of the genome that contribute to high levels of albumin in the urine, including one on chromosome 6. However, this region contains several genes and it was unclear which genes affected the condition. Schulz et al. set out to narrow down the list and find specific genes that might contribute to elevated albumin in the urine of rats with high blood pressure. This search identified the gene for a protein called TMEM63c as a likely candidate. This protein spans the outer membrane of podocyte cells. Analysis of kidney biopsies showed that patients with chronic kidney disease also had low levels of this protein in their podocytes. Further experiments, this time in zebrafish, showed that reducing the activity of the gene for tmem63c led to damaged podocytes and a leakier filter in the kidneys. The results suggest that this gene plays an important role in the integrity of the kidneys filtration barrier. It is possible that faulty versions of this gene are behind some cases of chronic kidney disease. If this proves to be the case, a better understanding of the role of this gene may lead to new treatments for the condition.
Collapse
Affiliation(s)
- Angela Schulz
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Institute of Clinical Pharmacology and Toxicology, Berlin Institute of Health, Berlin, Germany
| | - Nicola Victoria Müller
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Institute of Clinical Pharmacology and Toxicology, Berlin Institute of Health, Berlin, Germany.,Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Electrochemical Signaling in Development and Disease, Berlin, Germany
| | - Nina Anne van de Lest
- Department of Pathology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Andreas Eisenreich
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Institute of Clinical Pharmacology and Toxicology, Berlin Institute of Health, Berlin, Germany
| | - Martina Schmidbauer
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Institute of Clinical Pharmacology and Toxicology, Berlin Institute of Health, Berlin, Germany
| | - Andrei Barysenka
- Westfälische Wilhelms University, Genetic Epidemiology, Institute for Human Genetics, Münster, Germany
| | - Bettina Purfürst
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Core Facility Electron Microscopy, Berlin, Germany
| | - Anje Sporbert
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Advanced Light Microscopy, Berlin, Germany
| | - Theodor Lorenzen
- Institute of Clinical Pharmacology and Toxicology, Berlin Institute of Health, Berlin, Germany
| | | | - Laura Herlan
- Institute of Clinical Pharmacology and Toxicology, Berlin Institute of Health, Berlin, Germany
| | - Anika Witten
- Westfälische Wilhelms University, Genetic Epidemiology, Institute for Human Genetics, Münster, Germany
| | - Frank Rühle
- Westfälische Wilhelms University, Genetic Epidemiology, Institute for Human Genetics, Münster, Germany
| | - Weibin Zhou
- Division of Nephrology, Department of Medicine, Center for Human Disease Modeling, Duke University School of Medicine, Durham, United States
| | - Emile de Heer
- Department of Pathology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Marion Scharpfenecker
- Department of Pathology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Daniela Panáková
- DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Berlin, Germany
| | - Monika Stoll
- Westfälische Wilhelms University, Genetic Epidemiology, Institute for Human Genetics, Münster, Germany.,Department of Biochemistry, Maastricht University, Genetic Epidemiology and Statistical Genetics, Maastricht, The Netherlands
| | - Reinhold Kreutz
- Institute of Clinical Pharmacology and Toxicology, Berlin Institute of Health, Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Berlin, Germany
| |
Collapse
|
18
|
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.
Collapse
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
| | | |
Collapse
|
19
|
Giam B, Chu PY, Kuruppu S, Smith AI, Horlock D, Murali A, Kiriazis H, Du XJ, Kaye DM, Rajapakse NW. Serelaxin attenuates renal inflammation and fibrosis in a mouse model of dilated cardiomyopathy. Exp Physiol 2018; 103:1593-1602. [DOI: 10.1113/ep087189] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 10/11/2018] [Indexed: 01/04/2023]
Affiliation(s)
- Beverly Giam
- Baker Heart and Diabetes Institute; Melbourne Victoria Australia
- Central Clinical School; Monash University; Melbourne Victoria Australia
| | - Po-Yin Chu
- Baker Heart and Diabetes Institute; Melbourne Victoria Australia
| | - Sanjaya Kuruppu
- Biomedicine Discovery Institute; Department of Biochemistry & Molecular Biology; Monash University; Melbourne Victoria Australia
| | - A. Ian Smith
- Biomedicine Discovery Institute; Department of Biochemistry & Molecular Biology; Monash University; Melbourne Victoria Australia
| | - Duncan Horlock
- Baker Heart and Diabetes Institute; Melbourne Victoria Australia
| | - Aishwarya Murali
- Baker Heart and Diabetes Institute; Melbourne Victoria Australia
| | - Helen Kiriazis
- Baker Heart and Diabetes Institute; Melbourne Victoria Australia
| | - Xiao-Jun Du
- Baker Heart and Diabetes Institute; Melbourne Victoria Australia
| | - David M. Kaye
- Baker Heart and Diabetes Institute; Melbourne Victoria Australia
- Department of Medicine; Monash University; Melbourne Victoria Australia
| | - Niwanthi W. Rajapakse
- Baker Heart and Diabetes Institute; Melbourne Victoria Australia
- School of Biomedical Sciences; University of Queensland; Brisbane Queensland Australia
| |
Collapse
|
20
|
Chen NP, Sun Z, Fässler R. The Kank family proteins in adhesion dynamics. Curr Opin Cell Biol 2018; 54:130-136. [DOI: 10.1016/j.ceb.2018.05.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/25/2018] [Accepted: 05/30/2018] [Indexed: 01/24/2023]
|
21
|
Yu SMW, Nissaisorakarn P, Husain I, Jim B. Proteinuric Kidney Diseases: A Podocyte's Slit Diaphragm and Cytoskeleton Approach. Front Med (Lausanne) 2018; 5:221. [PMID: 30255020 PMCID: PMC6141722 DOI: 10.3389/fmed.2018.00221] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 07/18/2018] [Indexed: 01/19/2023] Open
Abstract
Proteinuric kidney diseases are a group of disorders with diverse pathological mechanisms associated with significant losses of protein in the urine. The glomerular filtration barrier (GFB), comprised of the three important layers, the fenestrated glomerular endothelium, the glomerular basement membrane (GBM), and the podocyte, dictates that disruption of any one of these structures should lead to proteinuric disease. Podocytes, in particular, have long been considered as the final gatekeeper of the GFB. This specialized visceral epithelial cell contains a complex framework of cytoskeletons forming foot processes and mediate important cell signaling to maintain podocyte health. In this review, we will focus on slit diaphragm proteins such as nephrin, podocin, TRPC6/5, as well as cytoskeletal proteins Rho/small GTPases and synaptopodin and their respective roles in participating in the pathogenesis of proteinuric kidney diseases. Furthermore, we will summarize the potential therapeutic options targeting the podocyte to treat this group of kidney diseases.
Collapse
Affiliation(s)
- Samuel Mon-Wei Yu
- Department of Medicine, Jacobi Medical Center, Bronx, NY, United States
| | | | - Irma Husain
- Department of Medicine, James J. Peters VA Medical Center, Bronx, NY, United States
| | - Belinda Jim
- Department of Medicine, Jacobi Medical Center, Bronx, NY, United States.,Renal Division, Jacobi Medical Center, Bronx, NY, United States
| |
Collapse
|
22
|
Guo Y, Pace J, Li Z, Ma'ayan A, Wang Z, Revelo MP, Chen E, Gu X, Attalah A, Yang Y, Estrada C, Yang VW, He JC, Mallipattu SK. Podocyte-Specific Induction of Krüppel-Like Factor 15 Restores Differentiation Markers and Attenuates Kidney Injury in Proteinuric Kidney Disease. J Am Soc Nephrol 2018; 29:2529-2545. [PMID: 30143559 PMCID: PMC6171275 DOI: 10.1681/asn.2018030324] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 08/02/2018] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Podocyte injury is the hallmark of proteinuric kidney diseases, such as FSGS and minimal change disease, and destabilization of the podocyte's actin cytoskeleton contributes to podocyte dysfunction in many of these conditions. Although agents, such as glucocorticoids and cyclosporin, stabilize the actin cytoskeleton, systemic toxicity hinders chronic use. We previously showed that loss of the kidney-enriched zinc finger transcription factor Krüppel-like factor 15 (KLF15) increases susceptibility to proteinuric kidney disease and attenuates the salutary effects of retinoic acid and glucocorticoids in the podocyte. METHODS We induced podocyte-specific KLF15 in two proteinuric murine models, HIV-1 transgenic (Tg26) mice and adriamycin (ADR)-induced nephropathy, and used RNA sequencing of isolated glomeruli and subsequent enrichment analysis to investigate pathways mediated by podocyte-specific KLF15 in Tg26 mice. We also explored in cultured human podocytes the potential mediating role of Wilms Tumor 1 (WT1), a transcription factor critical for podocyte differentiation. RESULTS In Tg26 mice, inducing podocyte-specific KLF15 attenuated podocyte injury, glomerulosclerosis, tubulointerstitial fibrosis, and inflammation, while improving renal function and overall survival; it also attenuated podocyte injury in ADR-treated mice. Enrichment analysis of RNA sequencing from the Tg26 mouse model shows that KLF15 induction activates pathways involved in stabilization of actin cytoskeleton, focal adhesion, and podocyte differentiation. Transcription factor enrichment analysis, with further experimental validation, suggests that KLF15 activity is in part mediated by WT1. CONCLUSIONS Inducing podocyte-specific KLF15 attenuates kidney injury by directly and indirectly upregulating genes critical for podocyte differentiation, suggesting that KLF15 induction might be a potential strategy for treating proteinuric kidney disease.
Collapse
Affiliation(s)
| | | | - Zhengzhe Li
- Division of Nephrology, Department of Medicine and
| | - Avi Ma'ayan
- Department of Pharmacological Sciences, Mount Sinai Center for Bioinformatics, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Zichen Wang
- Department of Pharmacological Sciences, Mount Sinai Center for Bioinformatics, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Monica P Revelo
- Department of Pathology, University of Utah, Salt Lake City, Utah
| | - Edward Chen
- Department of Pharmacological Sciences, Mount Sinai Center for Bioinformatics, Icahn School of Medicine at Mount Sinai, New York, New York
| | | | | | | | | | - Vincent W Yang
- Gastroenterology, Department of Medicine, Stony Brook University, Stony Brook, New York
| | - John C He
- Division of Nephrology, Department of Medicine and.,Department of Pharmacological Sciences, Mount Sinai Center for Bioinformatics, Icahn School of Medicine at Mount Sinai, New York, New York.,Renal Section, James J. Peters Veterans Affairs Medical Center, New York, New York; and
| | - Sandeep K Mallipattu
- Divisions of Nephrology and .,Renal Section, Northport Veterans Affairs Medical Center, Northport, New York
| |
Collapse
|
23
|
Gillies CE, Putler R, Menon R, Otto E, Yasutake K, Nair V, Hoover P, Lieb D, Li S, Eddy S, Fermin D, McNulty MT, Hacohen N, Kiryluk K, Kretzler M, Wen X, Sampson MG. An eQTL Landscape of Kidney Tissue in Human Nephrotic Syndrome. Am J Hum Genet 2018; 103:232-244. [PMID: 30057032 PMCID: PMC6081280 DOI: 10.1016/j.ajhg.2018.07.004] [Citation(s) in RCA: 124] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 06/29/2018] [Indexed: 01/14/2023] Open
Abstract
Expression quantitative trait loci (eQTL) studies illuminate the genetics of gene expression and, in disease research, can be particularly illuminating when using the tissues directly impacted by the condition. In nephrology, there is a paucity of eQTL studies of human kidney. Here, we used whole-genome sequencing (WGS) and microdissected glomerular (GLOM) and tubulointerstitial (TI) transcriptomes from 187 individuals with nephrotic syndrome (NS) to describe the eQTL landscape in these functionally distinct kidney structures. Using MatrixEQTL, we performed cis-eQTL analysis on GLOM (n = 136) and TI (n = 166). We used the Bayesian "Deterministic Approximation of Posteriors" (DAP) to fine-map these signals, eQTLBMA to discover GLOM- or TI-specific eQTLs, and single-cell RNA-seq data of control kidney tissue to identify the cell type specificity of significant eQTLs. We integrated eQTL data with an IgA Nephropathy (IgAN) GWAS to perform a transcriptome-wide association study (TWAS). We discovered 894 GLOM eQTLs and 1,767 TI eQTLs at FDR < 0.05. 14% and 19% of GLOM and TI eQTLs, respectively, had >1 independent signal associated with its expression. 12% and 26% of eQTLs were GLOM specific and TI specific, respectively. GLOM eQTLs were most significantly enriched in podocyte transcripts and TI eQTLs in proximal tubules. The IgAN TWAS identified significant GLOM and TI genes, primarily at the HLA region. In this study, we discovered GLOM and TI eQTLs, identified those that were tissue specific, deconvoluted them into cell-specific signals, and used them to characterize known GWAS alleles. These data are available for browsing and download via our eQTL browser, "nephQTL."
Collapse
Affiliation(s)
- Christopher E Gillies
- Department of Pediatrics-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Rosemary Putler
- Department of Pediatrics-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Rajasree Menon
- Department of Computational Medicine and Bioinformatics, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Edgar Otto
- Department of Medicine-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Kalyn Yasutake
- Department of Pediatrics-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Viji Nair
- Department of Medicine-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Paul Hoover
- Department of Medicine, Massachusetts General Hospital Cancer Center, Boston, MA 02114, USA; Broad Institute of the Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - David Lieb
- Broad Institute of the Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - Shuqiang Li
- Broad Institute of the Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - Sean Eddy
- Department of Medicine-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Damian Fermin
- Department of Pediatrics-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Michelle T McNulty
- Department of Pediatrics-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Nir Hacohen
- Department of Medicine, Massachusetts General Hospital Cancer Center, Boston, MA 02114, USA; Broad Institute of the Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - Krzysztof Kiryluk
- Department of Medicine, Division of Nephrology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
| | - Matthias Kretzler
- Department of Computational Medicine and Bioinformatics, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA; Department of Medicine-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Xiaoquan Wen
- Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor, MI 48109, USA
| | - Matthew G Sampson
- Department of Pediatrics-Nephrology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA.
| |
Collapse
|
24
|
Noone DG, Iijima K, Parekh R. Idiopathic nephrotic syndrome in children. Lancet 2018; 392:61-74. [PMID: 29910038 DOI: 10.1016/s0140-6736(18)30536-1] [Citation(s) in RCA: 272] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 02/15/2018] [Accepted: 02/23/2018] [Indexed: 12/19/2022]
Abstract
The incidence of idiopathic nephrotic syndrome (NS) is 1·15-16·9 per 100 000 children, varying by ethnicity and region. The cause remains unknown but the pathogenesis of idiopathic NS is thought to involve immune dysregulation, systemic circulating factors, or inherited structural abnormalities of the podocyte. Genetic risk is more commonly described among children with steroid-resistant disease. The mainstay of therapy is prednisone for the vast majority of patients who are steroid responsive; however, the disease can run a frequently relapsing course, necessitating the need for alternative immunosuppressive agents. Infection and venous thromboembolism are the main complications of NS with also increased risk of acute kidney injury. Prognosis in terms of long-term kidney outcome overall is excellent for steroid-responsive disease, and steroid resistance is an important determinant of future risk of chronic or end-stage kidney disease.
Collapse
Affiliation(s)
- Damien G Noone
- Department of Paediatrics, University of Toronto, Toronto, ON, Canada; Division of Nephrology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Rulan Parekh
- Department of Paediatrics, University of Toronto, Toronto, ON, Canada; Division of Nephrology, The Hospital for Sick Children, Toronto, ON, Canada; Child Health Evaluative Sciences, Research Institute, Hospital for Sick Children, Toronto, ON, Canada; University Health Network, Toronto, ON, Canada; Dalla Lana School of Public Health, and Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada.
| |
Collapse
|
25
|
Gonçalves S, Patat J, Guida MC, Lachaussée N, Arrondel C, Helmstädter M, Boyer O, Gribouval O, Gubler MC, Mollet G, Rio M, Charbit M, Bole-Feysot C, Nitschke P, Huber TB, Wheeler PG, Haynes D, Juusola J, Billette de Villemeur T, Nava C, Afenjar A, Keren B, Bodmer R, Antignac C, Simons M. A homozygous KAT2B variant modulates the clinical phenotype of ADD3 deficiency in humans and flies. PLoS Genet 2018; 14:e1007386. [PMID: 29768408 PMCID: PMC5973622 DOI: 10.1371/journal.pgen.1007386] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 05/29/2018] [Accepted: 04/30/2018] [Indexed: 12/25/2022] Open
Abstract
Recent evidence suggests that the presence of more than one pathogenic mutation in a single patient is more common than previously anticipated. One of the challenges hereby is to dissect the contribution of each gene mutation, for which animal models such as Drosophila can provide a valuable aid. Here, we identified three families with mutations in ADD3, encoding for adducin-γ, with intellectual disability, microcephaly, cataracts and skeletal defects. In one of the families with additional cardiomyopathy and steroid-resistant nephrotic syndrome (SRNS), we found a homozygous variant in KAT2B, encoding the lysine acetyltransferase 2B, with impact on KAT2B protein levels in patient fibroblasts, suggesting that this second mutation might contribute to the increased disease spectrum. In order to define the contribution of ADD3 and KAT2B mutations for the patient phenotype, we performed functional experiments in the Drosophila model. We found that both mutations were unable to fully rescue the viability of the respective null mutants of the Drosophila homologs, hts and Gcn5, suggesting that they are indeed pathogenic in flies. While the KAT2B/Gcn5 mutation additionally showed a significantly reduced ability to rescue morphological and functional defects of cardiomyocytes and nephrocytes (podocyte-like cells), this was not the case for the ADD3 mutant rescue. Yet, the simultaneous knockdown of KAT2B and ADD3 synergistically impaired kidney and heart function in flies as well as the adhesion and migration capacity of cultured human podocytes, indicating that mutations in both genes may be required for the full clinical manifestation. Altogether, our studies describe the expansion of the phenotypic spectrum in ADD3 deficiency associated with a homozygous likely pathogenic KAT2B variant and thereby identify KAT2B as a susceptibility gene for kidney and heart disease in ADD3-associated disorders.
Collapse
Affiliation(s)
- Sara Gonçalves
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Laboratory of Epithelial Biology and Disease, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Julie Patat
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Maria Clara Guida
- Development, Aging and Regeneration Program, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, United States of America
| | - Noelle Lachaussée
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Christelle Arrondel
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Martin Helmstädter
- Department of Medicine IV, Medical Center–University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Olivia Boyer
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
- Department of Pediatric Nephrology, Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Hôpital Necker-Enfants Malades, Assistance Publique—Hôpitaux de Paris (AP-HP), Paris, France
| | - Olivier Gribouval
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Marie-Claire Gubler
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Geraldine Mollet
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Marlène Rio
- Department of Genetics, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Marina Charbit
- Department of Pediatric Nephrology, Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Hôpital Necker-Enfants Malades, Assistance Publique—Hôpitaux de Paris (AP-HP), Paris, France
| | | | - Patrick Nitschke
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Tobias B. Huber
- Department of Medicine IV, Medical Center–University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- BIOSS Center for Biological Signalling Studies and Center for Systems Biology (ZBSA), Albert-Ludwigs-University, Freiburg, Germany
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Patricia G. Wheeler
- Division of Genetics, Arnold Palmer Hospital for Children, Orlando Health, Orlando, FL, United States of America
| | - Devon Haynes
- Division of Genetics, Arnold Palmer Hospital for Children, Orlando Health, Orlando, FL, United States of America
| | - Jane Juusola
- GeneDx, Inc, Gaithersburg, MD, United States of America
| | - Thierry Billette de Villemeur
- Sorbonne Université, UPMC, GRC ConCer-LD and AP-HP, Hôpital Trousseau, Service de Neuropédiatrie—Pathologie du développement, Paris, France
- Centre de référence des déficits intellectuels de causes rares, Inserm U 1141, Paris, France
| | - Caroline Nava
- Sorbonne Universités, UPMC Univ Paris 06, Inserm U1127, CNRS UMR 7225, Institut du Cerveau et de la Moèlle Épinière (ICM), Paris, France
- AP-HP, GH Pitié-Salpêtrière, Department of Genetics, Unit of Developmental Genomics, Paris, France
| | - Alexandra Afenjar
- AP-HP, Hôpital Trousseau, Centre de référence des malformations et maladies congénitales du cervelet, Département de génétique et embryologie médicale, Paris, France
| | - Boris Keren
- AP-HP, GH Pitié-Salpêtrière, Department of Genetics, Unit of Developmental Genomics, Paris, France
| | - Rolf Bodmer
- Development, Aging and Regeneration Program, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, United States of America
| | - Corinne Antignac
- Laboratory of Hereditary Kidney Diseases, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
- Department of Genetics, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
- * E-mail: (CA); (MS)
| | - Matias Simons
- Laboratory of Epithelial Biology and Disease, Institut National de la Santé et de la Recherche Médicale (Inserm) UMR1163, Imagine Institute, Paris, France
- Université Paris Descartes—Sorbonne Paris Cité, Imagine Institute, Paris, France
- * E-mail: (CA); (MS)
| |
Collapse
|
26
|
De Vriese AS, Sethi S, Nath KA, Glassock RJ, Fervenza FC. Differentiating Primary, Genetic, and Secondary FSGS in Adults: A Clinicopathologic Approach. J Am Soc Nephrol 2018; 29:759-774. [PMID: 29321142 DOI: 10.1681/asn.2017090958] [Citation(s) in RCA: 162] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
FSGS describes a renal histologic lesion with diverse causes and pathogenicities that are linked by podocyte injury and depletion. Subclasses of FSGS include primary, genetic, and secondary forms, the latter comprising maladaptive, viral, and drug-induced FSGS. Despite sharing certain clinical and histologic features, these subclasses differ noticeably in management and prognosis. Without an accepted nongenetic biomarker that discriminates among these FSGS types, classification of patients is often challenging. This review summarizes the clinical and histologic features, including the onset and severity of proteinuria as well as the presence of nephrotic syndrome, that may aid in identifying the specific FSGS subtype. The FSGS lesion is characterized by segmental sclerosis and must be differentiated from nonspecific focal global glomerulosclerosis. No light microscopic features are pathognomonic for a particular FSGS subcategory. The characteristics of podocyte foot process effacement on electron microscopy, while helpful in discriminating between primary and maladaptive FSGS, may be of little utility in detecting genetic forms of FSGS. When FSGS cannot be classified by clinicopathologic assessment, genetic analysis should be offered. Next generation DNA sequencing enables cost-effective screening of multiple genes simultaneously, but determining the pathogenicity of a detected genetic variant may be challenging. A more systematic evaluation of patients, as suggested herein, will likely improve therapeutic outcomes and the design of future trials in FSGS.
Collapse
Affiliation(s)
- An S De Vriese
- Division of Nephrology, AZ Sint-Jan Brugge-Oostende, Brugge, Belgium;
| | | | - Karl A Nath
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota; and
| | - Richard J Glassock
- Geffen School of Medicine at the University of California, Los Angeles, California
| | - Fernando C Fervenza
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota; and
| |
Collapse
|
27
|
Giam B, Kuruppu S, Chu PY, Smith AI, Marques FZ, Fiedler A, Horlock D, Kiriazis H, Du XJ, Kaye DM, Rajapakse NW. N-Acetylcysteine Attenuates the Development of Renal Fibrosis in Transgenic Mice with Dilated Cardiomyopathy. Sci Rep 2017; 7:17718. [PMID: 29255249 PMCID: PMC5735149 DOI: 10.1038/s41598-017-17927-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 12/01/2017] [Indexed: 02/02/2023] Open
Abstract
Mechanisms underlying the renal pathology in cardiorenal syndrome (CRS) type 2 remain elusive. We hypothesised that renal glutathione deficiency is central to the development of CRS type 2. Glutathione precursor, N-acetylcysteine (NAC;40 mg/kg/day; 8 weeks) or saline were administered to transgenic mice with dilated cardiomyopathy (DCM) and wild-type (WT) controls. Cardiac structure, function and glutathione levels were assessed at the end of this protocol. Renal fibrosis, glutathione content, expression of inflammatory and fibrotic markers, and function were also evaluated. In both genotypes, NAC had minimal effect on cardiac glutathione, structure and function (P ≥ 0.20). In NAC treated DCM mice, loss of glomerular filtration rate (GFR), tubulointerstitial and glomerular fibrosis and renal oxidised glutathione levels were attenuated by 38%, 99%, 70% and 52% respectively, compared to saline treated DCM mice (P ≤ 0.01). Renal expression of PAI-1 was greater in saline treated DCM mice than in WT mice (P < 0.05). Renal PAI-1 expression was less in NAC treated DCM mice than in vehicle treated DCM mice (P = 0.03). Renal IL-10 expression was greater in the former cohort compared to the latter (P < 0.01). These data indicate that normalisation of renal oxidized glutathione levels attenuates PAI-1 expression and renal inflammation preventing loss of GFR in experimental DCM.
Collapse
Affiliation(s)
- Beverly Giam
- Baker Heart and Diabetes Institute, Melbourne, Australia. .,Central Clinical School, Monash University, Melbourne, Australia.
| | - Sanjaya Kuruppu
- Biomedicine Discovery Institute, Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Australia
| | - Po-Yin Chu
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - A Ian Smith
- Biomedicine Discovery Institute, Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Australia
| | - Francine Z Marques
- Baker Heart and Diabetes Institute, Melbourne, Australia.,Central Clinical School, Monash University, Melbourne, Australia
| | - April Fiedler
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Duncan Horlock
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Helen Kiriazis
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Xiao-Jun Du
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - David M Kaye
- Baker Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine, Monash University, Melbourne, Australia
| | - Niwanthi W Rajapakse
- Baker Heart and Diabetes Institute, Melbourne, Australia.,School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, Australia
| |
Collapse
|
28
|
Éclaircissement du rôle d’APOL1 dans le rein. Nephrol Ther 2017; 13:569-571. [DOI: 10.1016/j.nephro.2017.08.352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 08/09/2017] [Indexed: 11/23/2022]
|
29
|
Suleiman HY, Roth R, Jain S, Heuser JE, Shaw AS, Miner JH. Injury-induced actin cytoskeleton reorganization in podocytes revealed by super-resolution microscopy. JCI Insight 2017; 2:94137. [PMID: 28814668 DOI: 10.1172/jci.insight.94137] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/07/2017] [Indexed: 02/06/2023] Open
Abstract
The architectural integrity of tissues requires complex interactions, both between cells and between cells and the extracellular matrix. Fundamental to cell and tissue homeostasis are the specific mechanical forces conveyed by the actomyosin cytoskeleton. Here we used super-resolution imaging methods to visualize the actin cytoskeleton in the kidney glomerulus, an organized collection of capillaries that filters the blood to make the primary urine. Our analysis of both mouse and human glomeruli reveals a network of myosin IIA-containing contractile actin cables within podocyte cell bodies and major processes at the outer aspects of the glomerular tuft. These likely exert force on an underlying network of myosin IIA-negative, noncontractile actin fibers present within podocyte foot processes that function to both anchor the cells to the glomerular basement membrane and stabilize the slit diaphragm against the pressure of fluid flow. After injuries that disrupt the kidney filtration barrier and cause foot process effacement, the podocyte's contractile actomyosin network relocates to the basolateral surface of the cell, manifesting as sarcomere-like structures juxtaposed to the basement membrane. Our findings suggest a new model of the podocyte actin cytoskeleton in health and disease and suggest the existence of novel mechanisms that regulate podocyte architecture.
Collapse
Affiliation(s)
- Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Robyn Roth
- Washington University Center for Cellular Imaging, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Sanjay Jain
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - John E Heuser
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Kyoto, Japan
| | | | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| |
Collapse
|
30
|
Translational science in chronic kidney disease. Clin Sci (Lond) 2017; 131:1617-1629. [PMID: 28667063 DOI: 10.1042/cs20160395] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/06/2017] [Accepted: 04/07/2017] [Indexed: 12/16/2022]
Abstract
The KDIGO definition of chronic kidney disease (CKD) allowed a more detailed characterization of CKD causes, epidemiology and consequences. The picture that has emerged is worrisome from the point of view of translation. CKD was among the fastest growing causes of death in the past 20 years in age-adjusted terms. The gap between recent advances and the growing worldwide mortality appears to result from sequential roadblocks that limit the flow from basic research to clinical development (translational research type 1, T1), from clinical development to clinical practice (translational research T2) and result in deficient widespread worldwide implementation of already available medical advances (translational research T3). We now review recent advances and novel concepts that have the potential to change the practice of nephrology in order to improve the outcomes of the maximal number of individuals in the shortest possible interval. These include: (i) updating the CKD concept, shifting the emphasis to the identification, risk stratification and care of early CKD and redefining the concept of aging-associated 'physiological' decline of renal function; (ii) advances in the characterization of aetiological factors, including challenging the concept of hypertensive nephropathy, the better definition of the genetic contribution to CKD progression, assessing the role of the liquid biopsy in aetiological diagnosis and characterizing the role of drugs that may be applied to the earliest stages of injury, such as SGLT2 inhibitors in diabetic kidney disease (DKD); (iii) embracing the complexity of CKD as a network disease and (iv) exploring ways to optimize implementation of existing knowledge.
Collapse
|
31
|
Beckerman P, Bi-Karchin J, Park ASD, Qiu C, Dummer PD, Soomro I, Boustany-Kari CM, Pullen SS, Miner JH, Hu CAA, Rohacs T, Inoue K, Ishibe S, Saleem MA, Palmer MB, Cuervo AM, Kopp JB, Susztak K. Transgenic expression of human APOL1 risk variants in podocytes induces kidney disease in mice. Nat Med 2017; 23:429-438. [PMID: 28218918 DOI: 10.1038/nm.4287] [Citation(s) in RCA: 249] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 01/20/2017] [Indexed: 02/07/2023]
Abstract
African Americans have a heightened risk of developing chronic and end-stage kidney disease, an association that is largely attributed to two common genetic variants, termed G1 and G2, in the APOL1 gene. Direct evidence demonstrating that these APOL1 risk alleles are pathogenic is still lacking because the APOL1 gene is present in only some primates and humans; thus it has been challenging to demonstrate experimental proof of causality of these risk alleles for renal disease. Here we generated mice with podocyte-specific inducible expression of the APOL1 reference allele (termed G0) or each of the risk-conferring alleles (G1 or G2). We show that mice with podocyte-specific expression of either APOL1 risk allele, but not of the G0 allele, develop functional (albuminuria and azotemia), structural (foot-process effacement and glomerulosclerosis) and molecular (gene-expression) changes that closely resemble human kidney disease. Disease development was cell-type specific and likely reversible, and the severity correlated with the level of expression of the risk allele. We further found that expression of the risk-variant APOL1 alleles interferes with endosomal trafficking and blocks autophagic flux, which ultimately leads to inflammatory-mediated podocyte death and glomerular scarring. In summary, this is the first demonstration that the expression of APOL1 risk alleles is causal for altered podocyte function and glomerular disease in vivo.
Collapse
Affiliation(s)
- Pazit Beckerman
- Renal Electrolyte and Hypertension Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jing Bi-Karchin
- Renal Electrolyte and Hypertension Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ae Seo Deok Park
- Renal Electrolyte and Hypertension Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Chengxiang Qiu
- Renal Electrolyte and Hypertension Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Patrick D Dummer
- Kidney Disease Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Irfana Soomro
- Division of Nephrology, New York University, New York, New York, USA
| | - Carine M Boustany-Kari
- Department of Cardiometabolic Diseases Research, Boehringer Ingelheim Pharmaceuticals, Ridgefield, Connecticut, USA
| | - Steven S Pullen
- Department of Cardiometabolic Diseases Research, Boehringer Ingelheim Pharmaceuticals, Ridgefield, Connecticut, USA
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Chien-An A Hu
- Department of Biochemistry and Molecular Biology, University of New Mexico School of Medicine and Health Sciences Center, Albuquerque, New Mexico, USA
| | - Tibor Rohacs
- Department of Pharmacology, Physiology &Neuroscience, Rutgers-New Jersey Medical School, Newark, New Jersey, USA
| | - Kazunori Inoue
- Division of Nephrology, Yale University, School of Medicine, New Haven, Connecticut, USA
| | - Shuta Ishibe
- Division of Nephrology, Yale University, School of Medicine, New Haven, Connecticut, USA
| | - Moin A Saleem
- Bristol Renal and Children's Renal Unit, School of Clinical Sciences, University of Bristol, Bristol, UK
| | - Matthew B Palmer
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ana Maria Cuervo
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, New York, New York, USA
| | - Jeffrey B Kopp
- Kidney Disease Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Katalin Susztak
- Renal Electrolyte and Hypertension Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| |
Collapse
|
32
|
Genetics of kidney disease in 2016: Ingenious tactics to unravel complex kidney disease genetics. Nat Rev Nephrol 2017; 13:67-68. [PMID: 28100908 DOI: 10.1038/nrneph.2016.192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
33
|
Abstract
Genetic studies of hereditary forms of nephrotic syndrome have identified several proteins that are involved in regulating the permselective properties of the glomerular filtration system. Further extensive research has elucidated the complex molecular basis of the glomerular filtration barrier and clearly established the pivotal role of podocytes in the pathophysiology of glomerular diseases. Podocyte architecture is centred on focal adhesions and slit diaphragms - multiprotein signalling hubs that regulate cell morphology and function. A highly interconnected actin cytoskeleton enables podocytes to adapt in order to accommodate environmental changes and maintain an intact glomerular filtration barrier. Actin-based endocytosis has now emerged as a regulator of podocyte integrity, providing an impetus for understanding the precise mechanisms that underlie the steady-state control of focal adhesion and slit diaphragm components. This Review outlines the role of actin dynamics and endocytosis in podocyte biology, and discusses how molecular heterogeneity in glomerular disorders could be exploited to deliver more rational therapeutic interventions, paving the way for targeted medicine in nephrology.
Collapse
|
34
|
Dettmar AK, Oh J. Infection-Related Focal Segmental Glomerulosclerosis in Children. BIOMED RESEARCH INTERNATIONAL 2016; 2016:7351964. [PMID: 27294131 PMCID: PMC4886048 DOI: 10.1155/2016/7351964] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Revised: 04/07/2016] [Accepted: 04/21/2016] [Indexed: 01/16/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS) is the most common cause of steroid resistant nephrotic syndrome in children. It describes a unique histological picture of glomerular damage resulting from several causes. In the majority of patients the causing agent is still unknown, but in some cases viral association is evident. In adults, the most established FSGS causing virus is the human immune-deficiency virus, which is related to a collapsing variant of FSGS. Nevertheless, other viruses are also suspected for causing a collapsing or noncollapsing variant, for example, hepatitis B virus, parvovirus B19, and Cytomegalovirus. Although the systemic infection mechanism is different for these viruses, there are similarities in the pathomechanism for the induction of FSGS. As the podocyte is the key structure in the pathogenesis of FSGS, a direct infection of these cells or immediate damage through the virus or viral components has to be considered. Although viral infections are a very rare cause for FSGS in children, the treating pediatric nephrologist has to be aware of a possible underlying infection, as this has a relevant impact on therapy and prognosis.
Collapse
Affiliation(s)
- Anne Katrin Dettmar
- Department of Pediatric Nephrology, University Children's Medical Clinic, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Jun Oh
- Department of Pediatric Nephrology, University Children's Medical Clinic, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| |
Collapse
|
35
|
|