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Al-Diab O, Sünkel C, Blanc E, Catar RA, Ashraf MI, Zhao H, Wang P, Rinschen MM, Fritsche-Guenther R, Grahammer F, Bachmann S, Beule D, Kirwan JA, Rajewsky N, Huber TB, Gürgen D, Kusch A. Sex-specific molecular signature of mouse podocytes in homeostasis and in response to pharmacological challenge with rapamycin. Biol Sex Differ 2024; 15:72. [PMID: 39278930 PMCID: PMC11404044 DOI: 10.1186/s13293-024-00647-7] [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: 04/26/2023] [Accepted: 08/30/2024] [Indexed: 09/18/2024] Open
Abstract
BACKGROUND Sex differences exist in the prevalence and progression of major glomerular diseases. Podocytes are the essential cell-type in the kidney which maintain the physiological blood-urine barrier, and pathological changes in podocyte homeostasis are critical accelerators of impairment of kidney function. However, sex-specific molecular signatures of podocytes under physiological and stress conditions remain unknown. This work aimed at identifying sexual dimorphic molecular signatures of podocytes under physiological condition and pharmacologically challenged homeostasis with mechanistic target of rapamycin (mTOR) inhibition. mTOR is a crucial regulator involved in a variety of physiological and pathological stress responses in the kidney and inhibition of this pathway may therefore serve as a general stress challenger to get fundamental insights into sex differences in podocytes. METHODS The genomic ROSAmT/mG-NPHS2 Cre mouse model was used which allows obtaining highly pure podocyte fractions for cell-specific molecular analyses, and vehicle or pharmacologic treatment with the mTOR inhibitor rapamycin was performed for 3 weeks. Subsequently, deep RNA sequencing and proteomics were performed of the isolated podocytes to identify intrinsic sex differences. Studies were supplemented with metabolomics from kidney cortex tissues. RESULTS Although kidney function and morphology remained normal in all experimental groups, RNA sequencing, proteomics and metabolomics revealed strong intrinsic sex differences in the expression levels of mitochondrial, translation and structural transcripts, protein abundances and regulation of metabolic pathways. Interestingly, rapamycin abolished prominent sex-specific clustering of podocyte gene expression and induced major changes only in male transcriptome. Several sex-biased transcription factors could be identified as possible upstream regulators of these sexually dimorphic responses. Concordant to transcriptomics, metabolomic changes were more prominent in males. Remarkably, high number of previously reported kidney disease genes showed intrinsic sexual dimorphism and/or different response patterns towards mTOR inhibition. CONCLUSIONS Our results highlight remarkable intrinsic sex-differences and sex-specific response patterns towards pharmacological challenged podocyte homeostasis which might fundamentally contribute to sex differences in kidney disease susceptibilities and progression. This work provides rationale and an in-depth database for novel targets to be tested in specific kidney disease models to advance with sex-specific treatment strategies.
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Affiliation(s)
- Ola Al-Diab
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Christin Sünkel
- Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Hannoversche Str 28, 10115, Berlin, Germany
| | - Eric Blanc
- Core Unit Bioinformatics, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Rusan Ali Catar
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Muhammad Imtiaz Ashraf
- Department of Surgery, Experimental Surgery, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Hongfan Zhao
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- Department of Urology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Pinchao Wang
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Markus M Rinschen
- III. Department of Medicine, University Hospital Hamburg Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Raphaela Fritsche-Guenther
- Metabolomics Platform, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Lindenberger Weg 80, 10117, Berlin, Germany
| | - Florian Grahammer
- III. Department of Medicine, University Hospital Hamburg Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Sebastian Bachmann
- Institute of Functional Anatomy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Dieter Beule
- Core Unit Bioinformatics, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Jennifer A Kirwan
- Metabolomics Platform, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Lindenberger Weg 80, 10117, Berlin, Germany
| | - Nikolaus Rajewsky
- Berlin Institute for Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Hannoversche Str 28, 10115, Berlin, Germany
- Department of Pediatric Oncology and Hematology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Tobias B Huber
- III. Department of Medicine, University Hospital Hamburg Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Dennis Gürgen
- Experimental Pharmacology & Oncology Berlin-Buch GmbH, 13125 Berlin-Buch, Germany
| | - Angelika Kusch
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany.
- BIH Biomedical Innovation Academy (BIA), Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany.
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Saad M, Mehawej C, Faour WH. Analysis of G-quadruplex forming sequences in podocytes-marker genes and their potential roles in inherited glomerular diseases. Heliyon 2023; 9:e20233. [PMID: 37809648 PMCID: PMC10559976 DOI: 10.1016/j.heliyon.2023.e20233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 08/04/2023] [Accepted: 09/14/2023] [Indexed: 10/10/2023] Open
Abstract
Nephrotic Syndrome is the most widespread pediatric kidney disorder. Genetic alterations in podocyte genes are thought to be responsible for the disease. G-quadruplexes are non-conventional guanine-rich DNA and RNA structures, which are commonly found in regulatory regions. This study examined the potential G-quadruplexes forming sequences in the promoters and gene bodies of podocyte-marker genes. High G-quadruplexes density was found in the vascular endothelial growth facto, cluster of differentiation-151, integrin subunit beta-4, metalloendopeptidase, Wilms tumor-1, integrin subunit beta-3, synaptopodin, and nephrin promoters. Vascular endothelial growth facto, cluster of differentiation-151 and integrin subunit beta-4 had the highest G-quadruplexes density in their gene bodies and promoters. Additionally, highly stable G-quadruplexes forming sequences were identified within all podocyte-marker genes. Furthermore, it is hypothesized that Wilms tumor-1 is capable of controlling the transcription of podocalyxin by binding to two possible G-quadruplexes forming motifs. We next analyzed the most frequently reported genetic mutations in the selected genes for their effect on DNA G-quadruplexes formation, and the thermodynamic stability of predicted RNA G-quadruplexes, using RNAfold. Importantly, the missense mutation c.121_122del in the nephrin gene reported in patients with NS type 1 affected DNA G-quadruplexes formation in this region as well as the thermodynamic stability of the corresponding RNA G-quadruplexes. Overall, we report the potential regulatory roles of G-quadruplexes in the etiology of nephrotic syndrome and their possible use as drug targets to treat kidney diseases.
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Affiliation(s)
- Mona Saad
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Cybel Mehawej
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Wissam H. Faour
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
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3
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Li R, Dong W, Chen Y, Tang T, Zhao X, Zhang L, Liang X. Effect of cyclosporine A on focal segmental glomerulosclerosis caused by MYO1E mutation in a Chinese adult patient: A case report. Medicine (Baltimore) 2023; 102:e32683. [PMID: 36705362 PMCID: PMC9875993 DOI: 10.1097/md.0000000000032683] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
RATIONALE Focal segmental glomerulosclerosis (FSGS) describes a renal histologic lesion with diverse causes and pathogenicities. Monogenic abnormalities which are associated with impaired function of podocyte could result in FSGS. Most of genetic FSGS do not respond to immunosuppressive agents and often develop end-stage kidney disease. We reported a case of FSGS caused by myosin1e (MYO1E) mutation, alleviated by cyclosporine A (CsA) and low-dose glucocorticoid. PATIENT CONCERNS The patient was a 38-year-old male with nephrotic range proteinuria. He didn't respond to prednisone 65mg/day. Kidney biopsy in our hospital showed FSGS with several hypoplasia and tiny loops. In addition, focal thickening and disorganization of the glomerular gasement membrane as well as diffuse foot process effacement were observed in electron microscope. DIAGNOSES Genetic testing indicated homozygous deletion mutation of MYO1E. The patient was diagnosed with genetic FSGS caused by MYO1E homozygous mutation. INTERVENTIONS The patient was treated with CsA 50mg twice a day and low-dose methylprednisolone. OUTCOMES CsA and low-dose glucocorticoid dramatically reduced proteinuria, and partial remission was attained in 3 years follow-up. LESSONS MYO1E autosomal recessive mutation was a rare FSGS causative mutation that might benefit from CsA treatment. However, the long-term effect of CsA on FSGS caused by this mutation should be investigated in the future.
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Affiliation(s)
- Ruizhao Li
- Department of Nephrology, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, China
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Wei Dong
- Department of Nephrology, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, China
| | - Yingwen Chen
- School of Medicine, South China University of Technology, Guangzhou, China
| | - Tianwei Tang
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Xingchen Zhao
- Department of Nephrology, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, China
| | - Li Zhang
- Department of Nephrology, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, China
| | - Xinling Liang
- Department of Nephrology, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, China
- * Correspondence: Xinling Liang, Department of Nephrology, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510080, China (e-mail: )
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Abdou M, Ramadan A, El-Agamy BE, EL-Farsy MS, Saleh EM. Mutational analysis of phospholipase C epsilon 1 gene in Egyptian children with steroid-resistant nephrotic syndrome. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2022. [DOI: 10.1186/s43042-022-00353-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Steroid-resistant nephrotic syndrome (SRNS) is characterized by unresponsiveness of nephrotic range proteinuria to standard steroid therapy, and is the main cause of childhood renal failure. The identification of more than 53 monogenic causes of SRNS has led researchers to focus on the genetic mutations related to the molecular mechanisms of the disease. Mutations in the PLCE1 gene, which encodes phospholipase C epsilon 1 (PLCε1), have been described in patients with early-onset SRNS characterized by progressive renal failure. In this study we screened for PLCE1 mutations in Egyptian children with SRNS. This is a descriptive case series study aiming to screen for PLCE1 gene mutations by direct sequencing of five exons—9, 12, 15, 19, 27—in 20 Egyptian children with SRNS who entered the Nephrology Unit, Faculty of Medicine, Ain-Shams University from November 2015 to December 2017. The variants detected were submitted to in silico analysis.
Results
We screened for mutations in five selected exons of PLCE1 gene. We identified seven variants in the five selected exons with homozygous and heterozygous inheritance pattern, two are intronic variants, two are silent variants, and three are missense variants. We identified four novel variants two are silent with no clinical significance and two are missense with uncertain clinical significance and pathogenic in-silico predictions; one p.Arg1230His in exon 12, the other is p.Glu1393Lys in exon 15.
Conclusions
We identified four novel mutations, findings which added to the registered SNP spectrum of the PLCE1 gene. These results widen the spectrum of PLCE1 gene mutations and support the importance of genetic testing in different populations of SRNS patients, therefore, to assess the vulnerability of Egyptian children to SRNS candidate genes, further studies needed on a larger number of cases which undoubtedly provide new insights into the pathogenic mechanisms of SRNS and might help in control of the patient. Additionally, the use of computational scoring and modeling tools may assist in the evaluation of the way in which the SNPs affect protein functionality.
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Tseng CC, Zheng RH, Lin TW, Chou CC, Shih YC, Liang SW, Lee HH. α-Actinin-4 recruits Shp2 into focal adhesions to potentiate ROCK2 activation in podocytes. Life Sci Alliance 2022; 5:5/11/e202201557. [PMID: 36096674 PMCID: PMC9468603 DOI: 10.26508/lsa.202201557] [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: 06/10/2022] [Revised: 08/20/2022] [Accepted: 08/22/2022] [Indexed: 11/24/2022] Open
Abstract
α-Actinin-4 is crucial in the regulation of Shp2 FA targeting to enhance ROCK2-mediated actomyosin contractility and thereby strengthening cell adhesion and cytoskeletal architecture in podocytes. Cell–matrix adhesions are mainly provided by integrin-mediated focal adhesions (FAs). We previously found that Shp2 is essential for FA maturation by promoting ROCK2 activation at FAs. In this study, we further delineated the role of α-actinin-4 in the FA recruitment and activation of Shp2. We used the conditional immortalized mouse podocytes to examine the role of α-actinin-4 in the regulation of Shp2 and ROCK2 signaling. After the induction of podocyte differentiation, Shp2 and ROCK2 were strongly activated, concomitant with the formation of matured FAs, stress fibers, and interdigitating intracellular junctions in a ROCK-dependent manner. Gene knockout of α-actinin-4 abolished the Shp2 activation and subsequently reduced matured FAs in podocytes. We also demonstrated that gene knockout of ROCK2 impaired the generation of contractility and interdigitating intercellular junctions. Our results reveal the role of α-actinin-4 in the recruitment of Shp2 at FAs to potentiate ROCK2 activation for the maintenance of cellular contractility and cytoskeletal architecture in the cultured podocytes.
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Affiliation(s)
- Chien-Chun Tseng
- Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ru-Hsuan Zheng
- Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ting-Wei Lin
- Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chih-Chiang Chou
- Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yu-Chia Shih
- Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Shao-Wei Liang
- Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Hsiao-Hui Lee
- Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan .,Center for Intelligent Drug Systems and Smart Bio-Devices (IDS2B), National Yang Ming Chiao Tung University, Taipei, Taiwan
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SAAD M, Shebaby M, Mehawej C, Faour W. New complementary python codes to locate Single Nucleotide Polymorphisms (SNPs) and Overlapping G-Quadruplex Sequences (G4s). MethodsX 2022; 9:101875. [PMID: 36249933 PMCID: PMC9563633 DOI: 10.1016/j.mex.2022.101875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 10/01/2022] [Indexed: 11/07/2022] Open
Abstract
G-quadruplexes (G4s) are non-canonical DNA and RNA secondary structures that control gene regulation. A single nucleotide polymorphism (SNP) is a small genetic variation occurring within a DNA sequence and accounting for the variabilities between individuals. While the majority of SNPs, especially those frequent in the population, are considered as benign genetic variations, few others can lead to diseases. SNPs occurring in G4 sequences were reported to modulate gene regulation. In order to find overlaps between predicted G4 sequences and SNPs located in the genomic regions, we developed two complementary computational python codes (SNP-locator and G4-overlap). The codes map a mutation to the overlapping/closest G4 sequences, based on the genetic variant name and the FASTA format of the corresponding gene. We validated these two codes on a set of 31 SNP variants occurring in cytochromes P450 genes and podocytes-marker genes. Out of 31 SNPs, 28 were accurately located using the mentioned codes.SNP-locator code locates any SNP in promoters, upstream regulatory regions, exons and introns. The SNP-locator code requires the FASTA genomic sequence of the studied gene and the genetic variant nomenclature at the cDNA level. G4-overlap code maps the SNP to the overlapping or the closest G4 sequence.
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Affiliation(s)
- Mona SAAD
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Marc Shebaby
- School of Arts and Sciences, Lebanese American University, Byblos, Lebanon
| | - Cybel Mehawej
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Wissam Faour
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon,Corresponding author.
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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.
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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
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8
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Effects of Genistein on Common Kidney Diseases. Nutrients 2022; 14:nu14183768. [PMID: 36145144 PMCID: PMC9506319 DOI: 10.3390/nu14183768] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/06/2022] [Accepted: 09/06/2022] [Indexed: 12/16/2022] Open
Abstract
Genistein is a naturally occurring phytoestrogen (soy or soybean products) that is classified as an isoflavone, and its structure is similar to that of endogenous estrogens; therefore, genistein can exert an estrogen-like effect via estrogen receptors. Additionally, genistein is a tyrosine kinase inhibitor, which enables it to block abnormal cell growth and proliferation signals through the inhibition of tyrosine kinase. Genistein is also an angiogenesis inhibitor and an antioxidant. Genistein has effects on kidney cells, some of the kidney’s physiological functions, and a variety of kidney diseases. First, genistein exerts a protective effect on normal cells by reducing the inflammatory response, inhibiting apoptosis, inhibiting oxidative stress, inhibiting remodeling, etc., but after cell injury, the protective effect of genistein decreases or even has the opposite effect. Second, genistein can regulate renin intake to maintain blood pressure balance, regulate calcium uptake to regulate Ca2+ and Pi balances, and reduce vasodilation to promote diuresis. Third, genistein has beneficial effects on a variety of kidney diseases (including acute kidney disease, kidney cancer, and different chronic kidney diseases), such as reducing symptoms, delaying disease progression, and improving prognosis. Therefore, this paper reviews animal and human studies on the protective effects of genistein on the kidney in vivo and in vitro to provide a reference for clinical research in the future.
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9
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Wang C, Liu J, Zhang X, Chen Q, Bai X, Hong X, Zhou L, Liu Y. Role of miRNA-671-5p in Mediating Wnt/β-Catenin-Triggered Podocyte Injury. Front Pharmacol 2022; 12:784489. [PMID: 35111054 PMCID: PMC8801877 DOI: 10.3389/fphar.2021.784489] [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: 09/27/2021] [Accepted: 12/09/2021] [Indexed: 12/22/2022] Open
Abstract
Podocyte injury and proteinuria are the most common features of glomerular disease, which is the leading cause of end-stage renal failure. Hyperactivated Wnt/β-catenin signaling is closely associated with podocyte injury, but the underlying mechanisms are incompletely understood. Here we show that miRNA-671-5p (miR-671-5p) plays a crucial role in mediating β-catenin-triggered podocyte injury by targeting Wilms tumor 1 (WT1). Microarray-based expression profiling revealed that miR-671-5p was the most upregulated miRNA in podocytes after β-catenin activation. MiR-671-5p was colocalized with β-catenin in the glomeruli of proteinuric CKD in vivo. Bioinformatics analyses and luciferase reporter assays confirmed that miR-671-5p targeted WT1 mRNA. Overexpression of miR-671-5p mimics inhibited WT1 and impaired podocyte integrity, whereas miR-671-5p antagomir preserved the expression of WT1 and other podocyte-specific proteins under basal conditions or after β-catenin activation. In mouse remnant kidney model, overexpression of miR-671-5p aggravated podocyte injury, worsened kidney dysfunction and exacerbated renal fibrosis after 5/6 nephrectomy. In contrast, miR-671-5p antagomir alleviated podocyte injury and attenuated proteinuria and renal fibrotic lesions after glomerular injury in vivo. These studies underscore a pivotal role of miR-671-5p in mediating WT1 depletion and podocyte injury induced by β-catenin. Targeting miR-671-5p may serve as a new approach to prevent podocyte injury and proteinuria in proteinuric CKD.
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Affiliation(s)
- Chunhong Wang
- Division of Nephrology, National Clinical Research Center of Kidney Disease, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jiafeng Liu
- Division of Nephrology, National Clinical Research Center of Kidney Disease, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiaoyao Zhang
- Division of Nephrology, National Clinical Research Center of Kidney Disease, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qiyan Chen
- Division of Nephrology, National Clinical Research Center of Kidney Disease, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiaoyan Bai
- Division of Nephrology, National Clinical Research Center of Kidney Disease, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xue Hong
- Division of Nephrology, National Clinical Research Center of Kidney Disease, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Lili Zhou
- Division of Nephrology, National Clinical Research Center of Kidney Disease, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Youhua Liu
- Division of Nephrology, National Clinical Research Center of Kidney Disease, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, China.,Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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Zhang F, Liu J, Yu J, Sun W, Wang Y, Fan T, Sun Y, Han X. Effect of Nephropathy Prescription I on the Expression of Angptl3 and Podocyte-Associated Protein in Mice with Adriamycin-Induced Nephropathy. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2022; 2022:9921679. [PMID: 38149181 PMCID: PMC10751164 DOI: 10.1155/2022/9921679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 12/12/2021] [Accepted: 12/23/2021] [Indexed: 12/28/2023]
Abstract
Objective This study aimed to investigate the effects of Nephropathy Prescription I on the expression of angptl3, nephrin, and podocin, in addition to its protective effects on podocytes in mice with adriamycin-induced nephropathy. Methods BALB/c mice were randomly divided into the control (C), adriamycin (Model or M), adriamycin + Nephropathy Prescription I (M + Z), adriamycin + prednisone acetate (M + S), and adriamycin + Nephropathy Prescription I + prednisone acetate groups (M + Z + S). All mice except those in the C group in the experimental groups were treated with a single tail vein injection of adriamycin. The urine albumin-creatinine ratio was measured before model establishment and on the 7th day, 14th day, 21st day, and 28th day of doxorubicin injection. All the mice were sacrificed on the 29th day. Blood samples were collected to observe biochemical indicators in the serum. The morphological structure and podocyte ultrastructure in the kidney were observed using light and electron microscopy, respectively. The expression of angptl3, nephrin, and podocin at the mRNA and protein levels was detected by real-time PCR and western blotting, respectively. Results Following modeling with adriamycin, albuminuria was observed in urine samples in the first week, and the urinary protein/creatinine ratio increased maximally in the fourth week in the M group (P < 0.05). In contrast, the urinary protein/creatinine ratio significantly decreased (P < 0.05) in the third week in the (M + Z) group compared to that in the M group. Similarly, this ratio decreased in the (M + S) and (M + Z + S) groups compared to that in the M group throughout the experiment. Compared with the C group, serum albumin content and the expression of nephrin and podocin decreased (P < 0.05), whereas blood lipid level and the expression of angptl3 increased (P < 0.05) in the M group. Glomerular foot process fusion was observed in this group using electron microscopy. In all the intervention groups, serum albumin content and the expression of nephrin and podocin increased (P < 0.05), whereas blood lipid level and the expression of angptl3 decreased (P < 0.05), with alleviated glomerular foot process injury observed particularly in the (M + Z + S) group. Conclusion The Nephropathy Prescription I can alleviate albuminuria, increase serum albumin levels, lower blood lipid levels, and reduce the fusion of foot processes of podocytes in mice with adriamycin-induced nephropathy. The protective effects of the Nephropathy Prescription I may function by reducing Angptl3 expression and increasing nephrin and podocin expression.
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Affiliation(s)
- Feifei Zhang
- Children's Hosptial of Fudan University Department of Traditional Chinese Medicine, Shanghai 201102, China
| | - Junchao Liu
- Children's Hosptial of Fudan University Department of Traditional Chinese Medicine, Shanghai 201102, China
| | - Jian Yu
- Children's Hosptial of Fudan University Department of Traditional Chinese Medicine, Shanghai 201102, China
| | - Wen Sun
- Children's Hosptial of Fudan University Department of Traditional Chinese Medicine, Shanghai 201102, China
| | - Yonghong Wang
- Children's Hosptial of Fudan University Department of Traditional Chinese Medicine, Shanghai 201102, China
| | - Teng Fan
- Children's Hosptial of Fudan University Department of Traditional Chinese Medicine, Shanghai 201102, China
| | - Yanyan Sun
- Children's Hosptial of Fudan University Department of Traditional Chinese Medicine, Shanghai 201102, China
| | - Xinghui Han
- Children's Hosptial of Fudan University Department of Traditional Chinese Medicine, Shanghai 201102, China
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Ultrasound combined with microbubbles enhances the renoprotective effects of methylprednisolone in rats with adriamycin-induced nephropathy. Eur J Pharm Sci 2021; 159:105714. [PMID: 33453390 DOI: 10.1016/j.ejps.2021.105714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 11/24/2020] [Accepted: 01/07/2021] [Indexed: 11/20/2022]
Abstract
The purpose of this study was to investigate the effect of ultrasound combined with microbbules (SonoVueTM) on the potency of methylprednisolone in attenuating the renal injury induced by adriamycin in rats. Animal model was established by two intravenous injections of 4 mg/kg adriamycin with a 2-week interval in rats. One week later, the adriamycin injected rats were randomly divided into 7 groups, receiving various treatments daily for 2 weeks. Two doses of methylprednisolone (20 or 40 mg/kg) were administrated alone or 20 mg/kg methylprednisolone and 100 µL SonoVueTM microbbules (1-5 × 108 bubbles/mL; mean diameter of bubbles: 2.5 µm) was co-administrated by intravenous injections from the tail vein. The ultrasound was applied at a frequency of 0.8 MHz and a spatial average temporal average intensity of 2.79 W/cm2 for 5 min at a 50% duty cycle (1 s on 1 s off) on the back skin of the anatomic position of the kidney in rats of two groups combined with ultrasound. Renal injury were analyzed using immunohistochemical staining, real-time PCR, light and transmission electron microcopies. The kidney function related biochemical indexes were measured by automatic biochemistry analyzer. The results showed that adriamycin induced a typical renal injury and 40 mg/kg methylprednisolone injection significantly ameliorated the abnormality of key parameters such as proteinuria, renal mRNA and protein expression levels of nephrin, collagens III and IV as well as podocyte impairment, glomerulosclerosis and tubulointerstitial injury indexes. However, a sub-dose of methylprednisolone at 20 mg/kg was ineffective when administered intravenously, but its potency at this dosage was enhanced by co-administration with 100 µL SonoVueTM microbubbles plus ultrasound irradiation. In conclusion, ultrasound combined with microbubbles can significantly increase local renal drug delivery leading to enhanced therapeutic effect of low dose methylprednisolone in ameliorating adriamycin-induced nephropathy in rats.
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Protein misfolding in endoplasmic reticulum stress with applications to renal diseases. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2020. [PMID: 31928726 DOI: 10.1016/bs.apcsb.2019.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Protein misfolding may be the result of a variety of different processes that disrupt the ability of a protein to form a thermodynamically stable tertiary structure that allows it to perform its proper function. In this chapter, we explore the nature of a protein's form that allows it to have a stable tertiary structure, and examine specific mutation that are known to occur in the coding regions of DNA that disrupt a protein's ability to be folded into a thermodynamically stable tertiary structure. We examine the consequences of these protein misfoldings in terms of the endoplasmic reticulum stress response and resulting unfolded protein response. These conditions are specifically related to renal diseases. Further, we explore novel therapeutics, pharmacological chaperones, that are being developed to alleviate the disease burden associated with protein misfolding caused by mutations. These interventions aim to stabilize protein folding intermediates and allow proper folding to occur as well as prevent protein aggregation and the resulting pathophysiological consequences.
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Zhao XC, Livingston MJ, Liang XL, Dong Z. Cell Apoptosis and Autophagy in Renal Fibrosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1165:557-584. [PMID: 31399985 DOI: 10.1007/978-981-13-8871-2_28] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Renal fibrosis is the final common pathway of all chronic kidney diseases progressing to end-stage renal diseases. Autophagy, a highly conserved lysosomal degradation pathway, plays important roles in maintaining cellular homeostasis in all major types of kidney cells including renal tubular cells as well as podocytes, mesangial cells and endothelial cells in glomeruli. Autophagy dysfunction is implicated in the pathogenesis of various renal pathologies. Here, we analyze the pathological role and regulation of autophagy in renal fibrosis and related kidney diseases in both glomeruli and tubulointerstitial compartments. Further research is expected to gain significant mechanistic insights and discover pathway-specific and kidney-selective therapies targeting autophagy to prevent renal fibrosis and related kidney diseases.
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Affiliation(s)
- Xing-Chen Zhao
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Man J Livingston
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University and Charlie Norwood VA Medical Center, Augusta, GA, 30912, USA
| | - Xin-Ling Liang
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
| | - Zheng Dong
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University and Charlie Norwood VA Medical Center, Augusta, GA, 30912, USA.
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Baek JH, Gomez IG, Wada Y, Roach A, Mahad D, Duffield JS. Deletion of the Mitochondrial Complex-IV Cofactor Heme A:Farnesyltransferase Causes Focal Segmental Glomerulosclerosis and Interferon Response. THE AMERICAN JOURNAL OF PATHOLOGY 2018; 188:2745-2762. [PMID: 30268775 DOI: 10.1016/j.ajpath.2018.08.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 08/02/2018] [Accepted: 08/06/2018] [Indexed: 01/31/2023]
Abstract
Mutations in mitochondrial DNA as well as nuclear-encoded mitochondrial proteins have been reported to cause tubulointerstitial kidney diseases and focal segmental glomerulosclerosis (FSGS). Recently, genes and pathways affecting mitochondrial turnover and permeability have been implicated in adult-onset FSGS. Furthermore, dysfunctioning mitochondria may be capable of engaging intracellular innate immune-sensing pathways. To determine the impact of mitochondrial dysfunction in FSGS and secondary innate immune responses, we generated Cre/loxP transgenic mice to generate a loss-of-function deletion mutation of the complex IV assembly cofactor heme A:farnesyltransferase (COX10) restricted to cells of the developing nephrons. These mice develop severe, early-onset FSGS with innate immune activation and die prematurely with kidney failure. Mutant kidneys showed loss of glomerular and tubular epithelial function, epithelial apoptosis, and, in addition, a marked interferon response. In vitro modeling of Cox10 deletion in primary kidney epithelium compromises oxygen consumption, ATP generation, and induces oxidative stress. In addition, loss of Cox10 triggers a selective interferon response, which may be caused by the leak of mitochondrial DNA into the cytosol activating the intracellular DNA sensor, stimulator of interferon genes. This new animal model provides a mechanism to study mitochondrial dysfunction in vivo and demonstrates a direct link between mitochondrial dysfunction and intracellular innate immune response.
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Affiliation(s)
- Jea-Hyun Baek
- Research and Development, Biogen Inc., Cambridge, Massachusetts.
| | - Ivan G Gomez
- Research and Development, Biogen Inc., Cambridge, Massachusetts; Division of Nephrology, Departments of Medicine and Pathology, University of Washington, Seattle, Washington
| | - Yukihiro Wada
- Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Allie Roach
- Research and Development, Biogen Inc., Cambridge, Massachusetts; Division of Nephrology, Departments of Medicine and Pathology, University of Washington, Seattle, Washington
| | - Don Mahad
- Centre for Clinical Brain Sciences, Anne Rowling Regenerative Neurology Clinic and Centre for Neuroregeneration, University of Edinburgh, Edinburgh, United Kingdom
| | - Jeremy S Duffield
- Research and Development, Biogen Inc., Cambridge, Massachusetts; Division of Nephrology, Departments of Medicine and Pathology, University of Washington, Seattle, Washington; Division of Nephrology, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts.
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Wang Y, Li Y, Zhang T, Chi Y, Liu M, Liu Y. Genistein and Myd88 Activate Autophagy in High Glucose-Induced Renal Podocytes In Vitro. Med Sci Monit 2018; 24:4823-4831. [PMID: 29999001 PMCID: PMC6069420 DOI: 10.12659/msm.910868] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Renal podocyte damage plays a crucial role in the development of diabetic nephropathy. Genistein is derived from a leguminous plant, and MyD88 and TRIF are adaptor molecules in the Toll-like receptor (TLR) signaling pathway, which may play a role in autophagy. In this study, we utilized an in vitro high glucose (HG)-treated podocyte model to investigate the effects and underlying mechanisms of Genistein and MyD88 or TRIF siRNA induced autophagy and renal protection. MATERIAL AND METHODS An immortalized mouse podocyte cell line was treated with HG, Genistein, chloroquine, and/or transfected with specific Myd88 and TRIF siRNAs. The formation of autophagosomes and related autophagic vacuoles were monitored by transmission electron microscopy. The expression of autophagy-related factors and podocyte structure and functional markers, including LC3, p62, p-mTOR, synaptopodin, and nephrin, were measured by Western blot, and LC3 and p-mTOR expression were also assessed by immunofluorescence. RESULTS We showed that HG transiently (after 6-h exposure) induced expression of the autophagy activation marker LC3-II in podocytes. Genistein treatment induced autophagy in both normal and HG-treated podocytes through inactivating mTOR signaling. Moreover, Genistein protected podocytes against chloroquine in HG-cultured conditions in vitro by maintaining the level of autophagy-related proteins. In addition, MyD88 siRNA downregulated expression of autophagy-related proteins, whereas Genistein treatment reversed these effects. CONCLUSIONS This study demonstrated that Genistein-induced autophagy could be a potential treatment strategy for glomerular diseases.
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Affiliation(s)
- Yuanyuan Wang
- Department of Nephrology, Hebei Medical University Third Affiliated Hospital, Shijiazhuang, Hebei, China (mainland)
| | - Ying Li
- Department of Nephrology, Hebei Medical University Third Affiliated Hospital, Shijiazhuang, Hebei, China (mainland)
| | - Tao Zhang
- Department of Nephrology, Hebei Medical University Third Affiliated Hospital, Shijiazhuang, Hebei, China (mainland)
| | - Yanqing Chi
- Department of Nephrology, Hebei Medical University Third Affiliated Hospital, Shijiazhuang, Hebei, China (mainland)
| | - Maodong Liu
- Department of Nephrology, Hebei Medical University Third Affiliated Hospital, Shijiazhuang, Hebei, China (mainland)
| | - Ying Liu
- Department of Science and Education, North China University of Science and Technology Affiliated Hospital, Tangshan, Hebei, China (mainland)
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Abid A, Shahid S, Shakoor M, Lanewala AA, Hashmi S, Khaliq S. Screening of the LAMB2, WT1, NPHS1, and NPHS2 Genes in Pediatric Nephrotic Syndrome. Front Genet 2018; 9:214. [PMID: 30013592 PMCID: PMC6036290 DOI: 10.3389/fgene.2018.00214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 05/25/2018] [Indexed: 02/04/2023] Open
Abstract
Mutations in the NPHS1, NPHS2, LAMB2, and the WT1 genes are responsible for causing nephrotic syndrome (NS) in two third of the early onset cases. This study was carried out to assess the frequencies of mutations in these genes in a cohort of pediatric NS patients. A total of 64 pediatric familial or sporadic SRNS cases were recruited. Among these, 74% had a disease onset of up to 3 years of age. We found one homozygous frameshift mutation in the NPHS1 gene in one CNS case and two homozygous mutations in the NPHS2 gene. Six mutations in four cases in the LAMB2 gene were also identified. No mutation was detected in the WT1 gene in isolated SRNS cases. LAMB2 gene missense mutations were segregating in NS cases with no extra-renal abnormalities. Analysis of the population genomic data (1000 genome and gnomAD databases) for the prevalence estimation revealed that NS is more prevalent than previously determined from clinical cohorts especially in Asian population compared with overall world populations (prevalence worldwide was 1in 189036 and in South-Asian was 1in 56689). Our results reiterated a low prevalence of mutations in the NPHS1, NPHS2, LAMB2, and WT1 genes in the studied population from Pakistan as compared to some European population that showed a high prevalence of mutations in these genes. This is a comprehensive screening of the genes causing early onset NS in sporadic and familial NS cases suggesting a more systematic and robust approach for mutation identification in all the 45 disease-causing genes in NS in our population is required.
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Affiliation(s)
- Aiysha Abid
- Centre for Human Genetics and Molecular Medicine, Sindh Institute of Urology and Transplantation, Karachi, Pakistan
| | - Saba Shahid
- Department of Genomic, National Institute of Blood Diseases, Karachi, Pakistan
| | - Madiha Shakoor
- Department of Human Genetics, University of Health Sciences, Lahore, Pakistan
| | - Ali A Lanewala
- Department of Pediatric Nephrology, Sindh Institute of Urology and Transplantation, Karachi, Pakistan
| | - Seema Hashmi
- Department of Pediatric Nephrology, Sindh Institute of Urology and Transplantation, Karachi, Pakistan
| | - Shagufta Khaliq
- Department of Human Genetics, University of Health Sciences, Lahore, Pakistan
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Takenaka T, Inoue T, Miyazaki T, Kobori H, Nishiyama A, Ishii N, Hayashi M, Suzuki H. Klotho suppresses the renin-angiotensin system in adriamycin nephropathy. Nephrol Dial Transplant 2018; 32:791-800. [PMID: 27798196 DOI: 10.1093/ndt/gfw340] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 08/10/2016] [Indexed: 11/13/2022] Open
Abstract
Backgrounds Klotho protein interacts with the transforming growth factor β (TGF-β) receptor and Wnt, which contribute to the progression of renal disease, inhibiting their signals. Renal and circulating klotho levels are diminished in chronic kidney disease. Methods Experiments were performed to assess whether supplementation of klotho protein could have protective effects on the kidney. Rats were injected with adriamycin (5 mg/kg) and divided into three groups: those treated with vehicle, those treated with klotho protein and those treated with klotho plus 4-benzyl-2-methyl-1,2,4-thiadiazolidine-3,5-dione (TDZD). Rats without adriamycin treatment were used as a control. Results Adriamycin reduced the serum klotho concentration and renal expression of klotho and E-cadherin. Adriamycin also increased the renal expression of Wnt, TGF-β, and angiotensinogen, as well as the renal abundance of β-catenin and angiotensin II. Klotho supplementation suppressed adriamycin-induced elevations of β-catenin and angiotensin II with sustained Wnt expression. Combined treatment with klotho and TDZD reversed the klotho-induced improvements in the renal abundance of β-catenin and angiotensin II as well as the expression of TGF-β and angiotensinogen without affecting E-cadherin. Conclusions Our data indicate that Wnt is involved in the pathogenesis of adriamycin nephropathy. Furthermore, klotho supplementation inhibited Wnt signaling, ameliorating renal angiotensin II. Finally, klotho protein appears to suppress epithelial-mesenchymal transition by inhibiting TGF-β and Wnt signaling.
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Affiliation(s)
- Tsuneo Takenaka
- Department of Medicine, International University of Health and Welfare, 8-10-16 Akasaka, Minato, Tokyo 107-0052, Japan
| | - Tsutomu Inoue
- Department of Nephrology, Saitama Medical University, Iruma, Saitama, Japan
| | - Takashi Miyazaki
- Department of Nephrology, Saitama Medical University, Iruma, Saitama, Japan
| | - Hiroyuki Kobori
- Department of Medicine, International University of Health and Welfare, 8-10-16 Akasaka, Minato, Tokyo 107-0052, Japan
| | - Akira Nishiyama
- Department of Pharmacology, Kagawa University, Kida, Kagawa, Japan
| | - Naohito Ishii
- Department of Clinical Chemistry, Kitasato University, Sagamihara, Kanagawa, Japan
| | | | - Hiromichi Suzuki
- Department of Nephrology, Saitama Medical University, Iruma, Saitama, Japan
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Lu Y, Ye Y, Bao W, Yang Q, Wang J, Liu Z, Shi S. Genome-wide identification of genes essential for podocyte cytoskeletons based on single-cell RNA sequencing. Kidney Int 2017; 92:1119-1129. [PMID: 28709640 DOI: 10.1016/j.kint.2017.04.022] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 04/06/2017] [Accepted: 04/13/2017] [Indexed: 12/21/2022]
Abstract
Gene expression differs substantially among individual cells of the same type. We speculate that genes that are expressed in all but a portion of cells of a given cell type would be likely essential and required for either the cell survival (housekeeping) or for the cell type's unique structure and function, enabling the organism to survive. Here, we performed RNA-seq of 20 mouse podocytes using the Fluidigm C1 system and identified 335 genes that were expressed in all of them. Among them, 239 genes were also expressed in mesangial and endothelial cells and were involved in energy metabolism, protein synthesis, etc., as housekeeping genes. In contrast, 92 genes were preferentially expressed in podocytes (over five-fold versus expression in mesangial and endothelial cells) and are, therefore, the essential candidate genes specific for podocytes. Assessments by bioinformatics, conserved expression in human podocytes, and association with injury/disease all support the essentiality of these genes for podocytes. Factually, 27 of the 92 genes are already known to be essential for podocyte structure and function. Thirty-seven novel genes were functionally analyzed by siRNA silencing, and we found that a deficiency of 30 genes led to either cytoskeletal injury (FGFR1, AOX1, AIF1L, HAUS8, RAB3B, LPIN2, GOLIM4, CERS6, ARHGEF18, ARPC1A, SRGAP1, ITGB5, ILDR2, MPP5, TSC22D1, DNAJC11, SEPT10, MOCS2, FNBP1L, and TMOD3) or significant downregulation of CD2AP and synaptopodin (IFT80, MYOM2, ANXA4, CYB5R4, GPC1, ZNF277, NSF, ITGAV, CRYAB, and MTSS1). Thus, the list of genes essential for podocyte cytoskeletons is expanded by single-cell RNA sequencing. It appears that podocyte-specific essential genes are mainly associated with podocyte cytoskeletons.
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Affiliation(s)
- Yuqiu Lu
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Yuting Ye
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Wenduona Bao
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Qianqian Yang
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Jinquan Wang
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Zhihong Liu
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China
| | - Shaolin Shi
- National Clinical Research Center for Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, China.
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Peng T, Li G, Zhong X, Wang L. Does copy number variation of APOL1 gene affect the susceptibility to focal segmental glomerulosclerosis? Ren Fail 2017; 39:500-504. [PMID: 28494221 PMCID: PMC6014314 DOI: 10.1080/0886022x.2017.1323646] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Background: APOL1 risk variants (G1 and G2) are associated with increased susceptibility to focal segmental glomerulosclerosis (FSGS) in African population. However, the two risk mutations were not found in Chinese FSGS patients. In this study, we explored the association between the copy number variation (CNV) of APOL1 gene and FSGS. Methods: APOL1 copy number variations were detected by quantitative real-time PCR with TaqMan probes and compared between 133 FSGS patients and 123 controls. The association between CNV of APOL1 gene and clinical parameters was also investigated. Results: The distribution of APOL1 CNV did not show significant difference between FSGS patients and controls. The creatinine and proteinuria in the high copy number group (CN ≥ 3) were higher than the other two groups, but the difference was not significant (p > .05). The FSGS pathological types were different among the three groups. Conclusion: There was no significant difference in the distribution of APOL1 gene copy variants between FSGS patients and normal controls, and there was no significant correlation between the APOL1 gene CNV and the FSGS patients’ clinical manifestations. APOL1 CNVs may be not associated with susceptibility to FSGS.
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Affiliation(s)
- Ting Peng
- a School of Medicine, University of Electronic Science and Technology of China, Renal Division and Institute of Nephrology , Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital , Chengdu , China
| | - Guisen Li
- a School of Medicine, University of Electronic Science and Technology of China, Renal Division and Institute of Nephrology , Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital , Chengdu , China
| | - Xiang Zhong
- a School of Medicine, University of Electronic Science and Technology of China, Renal Division and Institute of Nephrology , Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital , Chengdu , China
| | - Li Wang
- a School of Medicine, University of Electronic Science and Technology of China, Renal Division and Institute of Nephrology , Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital , Chengdu , China
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Tyutyunnykova A, Telegeev G, Dubrovska A. The controversial role of phospholipase C epsilon (PLCε) in cancer development and progression. J Cancer 2017; 8:716-729. [PMID: 28382133 PMCID: PMC5381159 DOI: 10.7150/jca.17779] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/23/2016] [Indexed: 01/21/2023] Open
Abstract
The phospholipase C (PLC) enzymes are important regulators of membrane phospholipid metabolism. PLC proteins can be activated by the receptor tyrosine kinases (RTK) or G-protein coupled receptors (GPCR) in response to the different extracellular stimuli including hormones and growth factors. Activated PLC enzymes hydrolyze phosphoinositides to increase the intracellular level of Ca2+ and produce diacylglycerol, which are important mediators of the intracellular signaling transduction. PLC family includes 13 isozymes belonging to 6 subfamilies according to their domain structures and functions. Although importance of PLC enzymes for key cellular functions is well established, the PLC proteins belonging to the ε, ζ and η subfamilies were identified and characterized only during the last decade. As a largest known PLC protein, PLCε is involved in a variety of signaling pathways and controls different cellular properties. Nevertheless, its role in carcinogenesis remains elusive. The aim of this review is to provide a comprehensive and up-to-date overview of the experimental and clinical data about the role of PLCε in the development and progression of the different types of human and experimental tumors.
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Affiliation(s)
- Anna Tyutyunnykova
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Fetscherstrasse 74, 01307 Dresden, Germany
| | - Gennady Telegeev
- The Institute of Molecular Biology and Genetics of NASU, Kyiv, Ukraine
| | - Anna Dubrovska
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Fetscherstrasse 74, 01307 Dresden, Germany.; German Cancer Consortium (DKTK), Dresden, Germany.; Deutsches Krebsforschungszentrum (DKFZ), Heidelberg, Germany
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Wang N, Wei RB, Li QP, Yang X, Chen XM. Protective effects of astragaloside in rats with adriamycin nephropathy and underlying mechanism. Chin J Nat Med 2017; 14:270-277. [PMID: 27114314 DOI: 10.1016/s1875-5364(16)30027-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Indexed: 10/21/2022]
Abstract
The present study was designed to determine the mechanism underlying the treatment of nephrotic syndrome using astragaloside by observing the effects of astragaloside on the expression of nephrin and podocin proteins and genes in kidneys of rats with adriamycin nephropathy. The rats were injected with adriamycin and, after successful model establishment, randomly divided into a model group, a Methylprednisolone (MP) group, and an astragaloside group. The 24-h complete urine samples were collected. Biochemical indicators were monitored, and kidney tissues were collected for pathological analysis using light microscopy and electron microscopy. The mRNA expression of nephrin and podocin was measured in the kidney tissues using the real-time qPCR, and the protein expression levels of nephrin and podocin were detected using Western blot analysis. At the end of 12 weeks of drug intervention, the urinary protein level was lower in the MP and astragaloside groups than that in the model group (P = 0.008 and P = 0.01, respectively). Serum albumin was higher in the MP and astragaloside groups than in the model group (P < 0.001 and P = 0.012, respectively). Podocytes in the MP group were nearly normal, and fusion of podocytes in the astragaloside group was significantly less than that in the control group. The nephrin and podocin mRNA and protein expression levels in the intervention groups were higher (P < 0.05) than that in the model group. Due to the increased expression of podocyte-related nephrin and podocin proteins, astragaloside maintained slit diaphragm integrity and decreased the level of proteinuria in rats with adriamycin nephropathy.
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Affiliation(s)
- Na Wang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China, 100853
| | - Ri-Bao Wei
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China, 100853.
| | - Qing-Ping Li
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China, 100853
| | - Xi Yang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China, 100853
| | - Xiang-Mei Chen
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China, 100853
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Zand L, Glassock RJ, De Vriese AS, Sethi S, Fervenza FC. What are we missing in the clinical trials of focal segmental glomerulosclerosis? Nephrol Dial Transplant 2017; 32:i14-i21. [DOI: 10.1093/ndt/gfw324] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 07/28/2016] [Indexed: 01/11/2023] Open
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Fakhruddin S, Alanazi W, Jackson KE. Diabetes-Induced Reactive Oxygen Species: Mechanism of Their Generation and Role in Renal Injury. J Diabetes Res 2017; 2017:8379327. [PMID: 28164134 PMCID: PMC5253173 DOI: 10.1155/2017/8379327] [Citation(s) in RCA: 166] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 12/07/2016] [Indexed: 02/07/2023] Open
Abstract
Diabetes induces the onset and progression of renal injury through causing hemodynamic dysregulation along with abnormal morphological and functional nephron changes. The most important event that precedes renal injury is an increase in permeability of plasma proteins such as albumin through a damaged glomerular filtration barrier resulting in excessive urinary albumin excretion (UAE). Moreover, once enhanced UAE begins, it may advance renal injury from progression of abnormal renal hemodynamics, increased glomerular basement membrane (GBM) thickness, mesangial expansion, extracellular matrix accumulation, and glomerulosclerosis to eventual end-stage renal damage. Interestingly, all these pathological changes are predominantly driven by diabetes-induced reactive oxygen species (ROS) and abnormal downstream signaling molecules. In diabetic kidney, NADPH oxidase (enzymatic) and mitochondrial electron transport chain (nonenzymatic) are the prominent sources of ROS, which are believed to cause the onset of albuminuria followed by progression to renal damage through podocyte depletion. Chronic hyperglycemia and consequent ROS production can trigger abnormal signaling pathways involving diverse signaling mediators such as transcription factors, inflammatory cytokines, chemokines, and vasoactive substances. Persistently, increased expression and activation of these signaling molecules contribute to the irreversible functional and structural changes in the kidney resulting in critically decreased glomerular filtration rate leading to eventual renal failure.
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Affiliation(s)
- Selim Fakhruddin
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe (ULM), Pharmacy Building, 1800 Bienville Dr., Monroe, LA 71201, USA
| | - Wael Alanazi
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe (ULM), Pharmacy Building, 1800 Bienville Dr., Monroe, LA 71201, USA
| | - Keith E. Jackson
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe (ULM), Pharmacy Building, 1800 Bienville Dr., Monroe, LA 71201, USA
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Cleper R, Krause I, Bar Nathan N, Mor M, Dagan A, Weissman I, Frishberg Y, Rachamimov R, Mor E, Davidovits M. Focal segmental glomerulosclerosis in pediatric kidney transplantation: 30 years’ experience. Clin Transplant 2016; 30:1324-1331. [DOI: 10.1111/ctr.12825] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2016] [Indexed: 12/16/2022]
Affiliation(s)
- Roxana Cleper
- Pediatric Nephrology Unit; Tel Aviv Sourasky Medical Center; Dana Dwek Children's Hospital; Tel Aviv Israel
- Institute of Nephrology; Schneider Children's Medical Center of Israel; Petah Tikva Israel
- Sackler Medical School; Tel Aviv University; Tel Aviv Israel
| | - Irit Krause
- Institute of Nephrology; Schneider Children's Medical Center of Israel; Petah Tikva Israel
- Sackler Medical School; Tel Aviv University; Tel Aviv Israel
- Pediatric Department C; Schneider Children's Medical Center of Israel; Petah Tikva Israel
| | - Nathan Bar Nathan
- Department of Transplantation; Rabin Medical Center; Beilinson Hospital; Petah Tikva Israel
| | - Maya Mor
- Department of Transplantation; Rabin Medical Center; Beilinson Hospital; Petah Tikva Israel
| | - Amit Dagan
- Institute of Nephrology; Schneider Children's Medical Center of Israel; Petah Tikva Israel
- Sackler Medical School; Tel Aviv University; Tel Aviv Israel
| | - Irith Weissman
- Department of Pediatric Nephrology and Dialysis; Western Galilee Hospital; Nahariya Israel
- The Faculty of Medicine in the Galilee; Bar Ilan University; Safed Israel
| | - Yaakov Frishberg
- Division of Pediatric Nephrology; Shaare Zedek Medical Center; Jerusalem Israel
- Hadassah-Hebrew University School of Medicine; Jerusalem Israel
| | - Ruty Rachamimov
- Sackler Medical School; Tel Aviv University; Tel Aviv Israel
- Department of Transplantation; Rabin Medical Center; Beilinson Hospital; Petah Tikva Israel
| | - Eitan Mor
- Sackler Medical School; Tel Aviv University; Tel Aviv Israel
- Department of Transplantation; Rabin Medical Center; Beilinson Hospital; Petah Tikva Israel
| | - Miriam Davidovits
- Institute of Nephrology; Schneider Children's Medical Center of Israel; Petah Tikva Israel
- Sackler Medical School; Tel Aviv University; Tel Aviv Israel
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Kato T, Mizuguchi N, Ito A. Characteristics of podocyte injury in malignant hypertensive nephropathy of rats (MSHRSP/Kpo strain). Biomed Res 2016; 36:313-21. [PMID: 26522148 DOI: 10.2220/biomedres.36.313] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Proteinuria is not only a hallmark of renal complication in malignant hypertension, but is also a major deteriorating factor for the progression to end-stage renal disease. Podocyte injury plays a crucial role in the renal damage associated with hypertensive nephropathy, but the underlying mechanism remains unclear. Malignant stroke-prone spontaneously hypertensive rats (MSHRSP/Kpo) represent an original and useful model of human malignant hypertension. In this study, we disclosed the glomerular injuries in the MSHRSP/Kpo. MSHRSP/Kpo exhibited elevated blood pressure at 6 weeks along with renal dysfunction and proteinuria. Histological analysis of the MSHRSP/Kpo glomeruli revealed a severe atrophy, but no change was found in the podocyte number. The expression levels of podocyte-specific proteins, nephrin, podocin, and synaptopodin were decreased in the MSHRSP/Kpo glomeruli, though another podocyte-specific protein, CD2AP, in the MSHRSP/Kpo glomeruli exhibited a similar extent of staining as in normotensive WKY/Kpo rats. Furthermore, desmin was not markedly detected in the WKY/Kpo glomeruli, but was strongly positive in MSHRSP/Kpo. By electron microscopy, well-formed foot processes (FP) were replaced by effacement in MSHRSP/Kpo. An original malignant hypertension strain MSHRSP/Kpo exhibits podocyte injuries associated with the decrease of some podocyte-specific proteins and the upregulation of desmin, along with FP effacement and proteinuria.
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Affiliation(s)
- Takashi Kato
- Department of Pharmacology, Faculty of Medicine, Kinki University
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FSGS: Diagnosis and Diagnostic Work-Up. BIOMED RESEARCH INTERNATIONAL 2016; 2016:4632768. [PMID: 27314022 PMCID: PMC4894996 DOI: 10.1155/2016/4632768] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 05/03/2016] [Indexed: 01/13/2023]
Abstract
Focal segmental glomerulosclerosis is a histologic lesion, rather than a clinical disease. FSGS is common cause of nephrotic syndrome in both adults and children worldwide. In the United States it is the most common primary glomerular disease resulting in end-stage renal disease and recent reports have suggested that its incidence might be on the rise. Currently the incidence is estimated to be 7 per million. The podocyte is the cellular target cell in FSGS and in recent years substantial insight in the pathogenesis and genetics of FSGS have accumulated. Furthermore the discovery of potential novel biomarkers to diagnose FSGS and monitor disease activity has renewed interest in this disease. In this review article we will focus on the clinical presentation and diagnosis of FSGS.
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Wang N, Wei RB, Li P, Li QP, Yang X, Yang Y, Huang MJ, Wang R, Yin Z, Lv Y, Chen XM. Treatment with irbesatan may improve slit diaphragm alterations in rats with adriamycin-induced nephropathy. J Renin Angiotensin Aldosterone Syst 2016; 17:1470320316646884. [PMID: 27169889 PMCID: PMC5843943 DOI: 10.1177/1470320316646884] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 03/27/2016] [Indexed: 12/19/2022] Open
Abstract
Objective: The study aimed to evaluate the effects of oral administration of irbesartan in adriamycin-induced nephropathy considering laboratory changes, kidney histology, and expression of proteins related to slit diaphragm and cytoskeleton of the podocyte. Methods: The animals were divided into control, model, methylprednisolone (MP), and irbesartan groups. The 24-hour urinary protein and biochemical indicators were determined, and renal pathological changes were observed. The mRNA and protein expression of nephrin, podocin, CD2-associated protein (CD2AP), and desmin in the kidney tissue were analyzed. Results: The urinary protein excretion levels in the MP and irbesartan groups were lower than those in the model group (p<0.01). Electron microscopy showed that fusion of the glomerular foot processes of the rats in the irbesartan group was significantly reduced. The mRNA and protein expression levels of nephrin and podocin in the renal tissue in the MP and irbesartan groups were up-regulated compared with the model group (p<0.05), whereas the mRNA and protein expression levels of CD2AP and desmin were significantly down-regulated (p<0.01). Conclusions: For rats with adriamycin-induced nephropathy, irbesartan could significantly reduce proteinuria. As a possible mechanism, irbesartan may improve the slit diaphragm protein of the glomerular podocyte and stabilize the cytoskeleton of the podocyte.
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Affiliation(s)
- Na Wang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Ri-bao Wei
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Ping Li
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Qing-ping Li
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Xi Yang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Yue Yang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Meng-jie Huang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Rui Wang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Zhong Yin
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Yang Lv
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
| | - Xiang-mei Chen
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, PR China
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Sampson MG, Pollak MR. Opportunities and Challenges of Genotyping Patients With Nephrotic Syndrome in the Genomic Era. Semin Nephrol 2016. [PMID: 26215859 DOI: 10.1016/j.semnephrol.2015.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Both targeted and genome-wide linkage and association studies have identified a number of genes and genetic variants associated with nephrotic syndrome (NS). Genotype-phenotype studies of patients with these variants have identified correlations of clear clinical significance. Combined with improved genomic technologies, this has resulted in increasing, and justifiable, enthusiasm for incorporating our patients' genomic information into our clinical management decisions. Here, we summarize our understanding of NS-associated genetic factors, namely rare causal mutations or common risk alleles in apolipoprotein L1. We discuss the complexities inherent in trying to ascribe risk or causality to these variants, particularly as we seek to extend genetic testing to a broader group of patients, including many with sporadic disease. Overall, the thoughtful application and interpretation of these genetic tests will maximize the benefits to our patients with NS in the form of more precise clinical care.
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Affiliation(s)
- Matthew G Sampson
- Department of Pediatrics, Division of Nephrology, University of Michigan School of Medicine, Ann Arbor, MI.
| | - Martin R Pollak
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
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30
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Focal segmental glomerular sclerosis: do not overlook the role of immune response. J Nephrol 2016; 29:525-34. [DOI: 10.1007/s40620-016-0272-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/28/2016] [Indexed: 10/22/2022]
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Abstract
Podocytes are highly specialized cells of the kidney glomerulus that wrap around capillaries and that neighbor cells of the Bowman’s capsule. When it comes to glomerular filtration, podocytes play an active role in preventing plasma proteins from entering the urinary ultrafiltrate by providing a barrier comprising filtration slits between foot processes, which in aggregate represent a dynamic network of cellular extensions. Foot processes interdigitate with foot processes from adjacent podocytes and form a network of narrow and rather uniform gaps. The fenestrated endothelial cells retain blood cells but permit passage of small solutes and an overlying basement membrane less permeable to macromolecules, in particular to albumin. The cytoskeletal dynamics and structural plasticity of podocytes as well as the signaling between each of these distinct layers are essential for an efficient glomerular filtration and thus for proper renal function. The genetic or acquired impairment of podocytes may lead to foot process effacement (podocyte fusion or retraction), a morphological hallmark of proteinuric renal diseases. Here, we briefly discuss aspects of a contemporary view of podocytes in glomerular filtration, the patterns of structural changes in podocytes associated with common glomerular diseases, and the current state of basic and clinical research.
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Affiliation(s)
- Jochen Reiser
- Department of Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Mehmet M Altintas
- Department of Medicine, Rush University Medical Center, Chicago, IL, USA
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32
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Takenaka T, Inoue T, Miyazaki T, Nishiyama A, Ishii N, Hayashi M, Suzuki H. Antialbuminuric actions of calcilytics in the remnant kidney. Am J Physiol Renal Physiol 2015; 309:F216-26. [PMID: 26017971 DOI: 10.1152/ajprenal.00003.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Hyperphosphatemia accelerates the progression of chronic kidney diseases. In the present study, the effects of ronacaleret, a calcilytic agent, on renal injury were assessed in the following four groups of rats: 5/6-nephrectomized Wistar rats as a control (C group), rats treated with ronacaleret (3 mg·kg(-1)·day(-1); R group), rats treated with calcitriol (30 ng·kg(-1)·day(-1); V group), and rats treated with both ronacaleret and calcitriol (R + V group). Three months later, rats were euthanized under anesthesia, and the remnant kidneys were harvested for analysis. Albuminuria was lower in the R and V groups than in the C group (P < 0.05). Creatinine clearance was elevated in the R and V groups compared with the C group (P < 0.05). Serum Ca(2+) and renal ANG II were higher in the R + V group than in the C group (P < 0.05 for each), and serum phosphate was reduced in the R group compared with the C group (P < 0.05). Fibroblast growth factor-23 was lower in the R group and higher in the V and R + V groups than in the C group. However, parathyroid hormone did not differ significantly among the four groups. Renal klotho expression was elevated in the R and V groups compared with the C group (P < 0.05). The present data indicate that ronacaleret preserves klotho expression and renal function with reductions in serum phosphate and albuminuria in 5/6-nephrectomized rats. Our findings demonstrate that vitamin D prevents declines in klotho expression and renal function, suppressing albuminuria.
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Affiliation(s)
- Tsuneo Takenaka
- International University of Health and Welfare, Minato, Tokyo, Japan;
| | | | | | | | - Naohito Ishii
- Kitasato University, Sagamihara, Kanagawa, Japan; and
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Kawakami T, Gomez IG, Ren S, Hudkins K, Roach A, Alpers CE, Shankland SJ, D'Agati VD, Duffield JS. Deficient Autophagy Results in Mitochondrial Dysfunction and FSGS. J Am Soc Nephrol 2015; 26:1040-52. [PMID: 25406339 PMCID: PMC4413752 DOI: 10.1681/asn.2013111202] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 07/07/2014] [Indexed: 12/20/2022] Open
Abstract
FSGS is a heterogeneous fibrosing disease of the kidney, the cause of which remains poorly understood. In most cases, there is no effective treatment to halt or retard progression to renal failure. Increasing evidence points to mitochondrial dysfunction and the generation of reactive oxygen species in the pathogenesis of CKD. Autophagy, a major intracellular lysosomal degradation system, performs homeostatic functions linked to metabolism and organelle turnover. We prevented normal autophagic pathways in nephrons of mice by mutating critical autophagy genes ATG5 or ATG7 during nephrogenesis. Mutant mice developed mild podocyte and tubular dysfunction within 2 months, profound glomerular and tubular changes bearing close similarity to human disease by 4 months, and organ failure by 6 months. Ultrastructurally, podocytes and tubular cells showed vacuolization, abnormal mitochondria, and evidence of endoplasmic reticulum stress, features that precede the appearance of histologic or clinical disease. Similar changes were observed in human idiopathic FSGS kidney biopsy specimens. Biochemical analysis of podocytes and tubules of 2-month-old mutant mice revealed elevated production of reactive oxygen species, activation of endoplasmic reticulum stress pathways, phosphorylation of p38, and mitochondrial dysfunction. Furthermore, cultured proximal tubule cells isolated from mutant mice showed marked mitochondrial dysfunction and elevated mitochondrial reactive oxygen species generation that was suppressed by a mitochondrial superoxide scavenger. We conclude that mitochondrial dysfunction and endoplasmic reticulum stress due to impaired autophagic organelle turnover in podocytes and tubular epithelium are sufficient to cause many of the manifestations of FSGS in mice.
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Affiliation(s)
- Takahisa Kawakami
- Division of Nephrology, Departments of Medicine & Pathology, and Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington; Division of Nephrology and Endocrinology, The University of Tokyo, Tokyo, Japan
| | - Ivan G Gomez
- Division of Nephrology, Departments of Medicine & Pathology, and Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington; Division of Nephrology and Endocrinology, The University of Tokyo, Tokyo, Japan
| | - Shuyu Ren
- Division of Nephrology, Departments of Medicine & Pathology, and Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington; Biogen Idec, Inc., Cambridge, Massachusetts; and
| | - Kelly Hudkins
- Division of Nephrology, Departments of Medicine & Pathology, and
| | - Allie Roach
- Division of Nephrology, Departments of Medicine & Pathology, and Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington; Biogen Idec, Inc., Cambridge, Massachusetts; and
| | - Charles E Alpers
- Division of Nephrology, Departments of Medicine & Pathology, and
| | | | | | - Jeremy S Duffield
- Division of Nephrology, Departments of Medicine & Pathology, and Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, Washington; Biogen Idec, Inc., Cambridge, Massachusetts; and
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Bazzi C, Rizza V, Olivieri G, Casellato D, D'Amico G. Tubular reabsorption of high, middle and low molecular weight proteins according to the tubulo-interstitial damage marker N-acetyl-β-D-glucosaminidase in glomerulonephritis. J Nephrol 2014; 28:541-8. [PMID: 25227764 DOI: 10.1007/s40620-014-0139-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 09/01/2014] [Indexed: 01/16/2023]
Abstract
BACKGROUND Proteinuria, the hallmark of glomerular diseases, is an independent predictor of end-stage renal disease (ESRD) progression. Proteinuria is a mixture of proteins of different molecular weight (MW) dependent on alterations of glomerular filtration barrier (GFB) and reabsorption impairment by proximal tubular epithelial cells (PTECs). We aimed to evaluate the excretion of different-MW proteins according to the tubulo-interstitial damage marker N-acetyl-β-D-glucosaminidase (NAG) in glomerulonephritides (GNs). METHODS In 189 patients [idiopathic membranous nephropathy (IMN) n = 84, primary focal segmental glomerulosclerosis (FSGS) n = 48, crescentic IgA nephropathy (CIgAN) n = 37, minimal change disease (MCD) n = 20] several urinary proteins were measured at biopsy: α2-macroglobulin/creatinine ratio; fractional excretion of IgG, transferrin, albumin and α1-microglobulin, and the NAG/creatinine ratio divided by estimated glomerular filtration rate (eGFR) (NAG/C/eGFR), as NAG excretion is dependent on functioning nephron mass. Protein excretion was compared between 4th vs. 1st quartile of NAG/C/eGFR. RESULTS In IMN, FSGS and CIgAN high-MW proteins excretion (α2-macroglobulin, IgG) was greater than that of middle- (transferrin, albumin) and low-MW proteins (α1-microglobulin) in 4th vs. 1st quartile of NAG/C/eGFR; the mean fold excretion increase of high-MW proteins in 3 GNs was 74.9, higher than that of middle- (34.8) and low-MW proteins (12.0). Higher excretion of high-MW proteins may be dependent on lower reabsorption by PTECs. By contrast, in MCD the difference in excretion of different-MW proteins is probably due to high GFB selectivity. CONCLUSION High-MW protein excretion is dependent on GFB alteration and reduced reabsorption; its prognostic significance is ominous because in several glomerular diseases progression is associated with high-MW protein excretion.
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Affiliation(s)
- Claudio Bazzi
- D'Amico Foundation for Renal Diseases Research, Via Cherubini 6, 20145, Milan, Italy.
| | - Virginia Rizza
- Biochemical Laboratory, San Carlo Borromeo Hospital, Milan, Italy
| | - Giulia Olivieri
- Biochemical Laboratory, San Carlo Borromeo Hospital, Milan, Italy
| | - Daniela Casellato
- Nephrology and Dialysis Unit, San Carlo Borromeo Hospital, Milan, Italy
| | - Giuseppe D'Amico
- D'Amico Foundation for Renal Diseases Research, Via Cherubini 6, 20145, Milan, Italy
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Zhou L, Li Y, He W, Zhou D, Tan RJ, Nie J, Hou FF, Liu Y. Mutual antagonism of Wilms' tumor 1 and β-catenin dictates podocyte health and disease. J Am Soc Nephrol 2014; 26:677-91. [PMID: 25071087 DOI: 10.1681/asn.2013101067] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Activation of β-catenin, the intracellular mediator of canonical Wnt signaling, has a critical role in mediating podocyte injury and proteinuria. However, the underlying mechanisms remain poorly understood. Here, we show that β-catenin triggers ubiquitin-mediated protein degradation of Wilms' tumor 1 (WT1) and functionally antagonizes its action. In mice injected with adriamycin, WT1 protein was progressively lost in glomerular podocytes at 1, 3, and 5 weeks after injection. Notably, loss of WT1 apparently did not result from podocyte depletion but was closely associated with upregulation of β-catenin. This change in WT1/β-catenin ratio was accompanied by loss of podocyte-specific nephrin, podocalyxin, and synaptopodin and acquisition of mesenchymal markers Snail1, α-smooth muscle actin, and fibroblast-specific protein 1. In vitro, overexpression of β-catenin induced WT1 protein degradation through the ubiquitin proteasomal pathway, which was blocked by MG-132. WT1 and β-catenin also competed for binding to common transcriptional coactivator CREB-binding protein and mutually repressed the expression of their respective target genes. In glomerular miniorgan culture, activation of β-catenin by Wnt3a repressed WT1 and its target gene expression. In vivo, blockade of Wnt/β-catenin signaling by endogenous antagonist Klotho induced WT1 and restored podocyte integrity in adriamycin nephropathy. These results show that β-catenin specifically targets WT1 for ubiquitin-mediated degradation, leading to podocyte dedifferentiation and mesenchymal transition. Our data also suggest that WT1 and β-catenin have opposing roles in podocyte biology, and that the ratio of their expression levels dictates the state of podocyte health and disease in vivo.
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Affiliation(s)
- Lili Zhou
- State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, China; and Department of Pathology and
| | | | | | | | - Roderick J Tan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Jing Nie
- State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, China; and
| | - Fan Fan Hou
- State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, China; and
| | - Youhua Liu
- State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, China; and Department of Pathology and
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Giglio S, Provenzano A, Mazzinghi B, Becherucci F, Giunti L, Sansavini G, Ravaglia F, Roperto RM, Farsetti S, Benetti E, Rotondi M, Murer L, Lazzeri E, Lasagni L, Materassi M, Romagnani P. Heterogeneous genetic alterations in sporadic nephrotic syndrome associate with resistance to immunosuppression. J Am Soc Nephrol 2014; 26:230-6. [PMID: 25060053 DOI: 10.1681/asn.2013111155] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
In children, sporadic nephrotic syndrome can be related to a genetic cause, but to what extent genetic alterations associate with resistance to immunosuppression is unknown. In this study, we designed a custom array for next-generation sequencing analysis of 19 target genes, reported as possible causes of nephrotic syndrome, in a cohort of 31 children affected by sporadic steroid-resistant nephrotic syndrome and 38 patients who exhibited a similar but steroid-sensitive clinical phenotype. Patients who exhibited extrarenal symptoms, had a familial history of the disease or consanguinity, or had a congenital onset were excluded. We identified a genetic cause in 32.3% of the children with steroid-resistant disease but zero of 38 children with steroid-sensitive disease. Genetic alterations also associated with lack of response to immunosuppressive agents in children with steroid-resistant disease (0% of patients with alterations versus 57.9% of patients without alterations responded to immunosuppressive agents), whereas clinical features, age at onset, and pathologic findings were similar in steroid-resistant patients with and without alterations. These results suggest that heterogeneous genetic alterations in children with sporadic forms of nephrotic syndrome associate with resistance to steroids as well as immunosuppressive treatments. In these patients, a comprehensive screening using such an array may, thus, be useful for genetic counseling and may help clinical decision making in a fast and cost-efficient manner.
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Affiliation(s)
- Sabrina Giglio
- Department of Biomedical Experimental and Clinical Sciences "Mario Serio," and Medical Genetics and
| | - Aldesia Provenzano
- Department of Biomedical Experimental and Clinical Sciences "Mario Serio," and
| | | | - Francesca Becherucci
- Pediatric Nephrology Units, Meyer Children's University Hospital, Florence, Italy
| | | | - Giulia Sansavini
- Pediatric Nephrology Units, Meyer Children's University Hospital, Florence, Italy
| | - Fiammetta Ravaglia
- Pediatric Nephrology Units, Meyer Children's University Hospital, Florence, Italy
| | - Rosa Maria Roperto
- Pediatric Nephrology Units, Meyer Children's University Hospital, Florence, Italy
| | - Silvia Farsetti
- Pediatric Nephrology Units, Meyer Children's University Hospital, Florence, Italy
| | - Elisa Benetti
- Department of Pediatrics, University of Padua, Padua, Italy; and
| | - Mario Rotondi
- Unit of Internal Medicine and Endocrinology, Fondazione Salvatore Maugeri IRCCS, University of Pavia, Pavia, Italy
| | - Luisa Murer
- Department of Pediatrics, University of Padua, Padua, Italy; and
| | - Elena Lazzeri
- Excellence Centre for Research, Transfer and High Education for the Development of DE NOVO Therapies (DENOTHE), University of Florence, Florence, Italy
| | - Laura Lasagni
- Excellence Centre for Research, Transfer and High Education for the Development of DE NOVO Therapies (DENOTHE), University of Florence, Florence, Italy
| | - Marco Materassi
- Pediatric Nephrology Units, Meyer Children's University Hospital, Florence, Italy
| | - Paola Romagnani
- Department of Biomedical Experimental and Clinical Sciences "Mario Serio," and Pediatric Nephrology Units, Meyer Children's University Hospital, Florence, Italy; Excellence Centre for Research, Transfer and High Education for the Development of DE NOVO Therapies (DENOTHE), University of Florence, Florence, Italy;
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Lovric S, Fang H, Vega-Warner V, Sadowski CE, Gee HY, Halbritter J, Ashraf S, Saisawat P, Soliman NA, Kari JA, Otto EA, Hildebrandt F. Rapid detection of monogenic causes of childhood-onset steroid-resistant nephrotic syndrome. Clin J Am Soc Nephrol 2014; 9:1109-16. [PMID: 24742477 DOI: 10.2215/cjn.09010813] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND AND OBJECTIVES In steroid-resistant nephrotic syndrome (SRNS), >21 single-gene causes are known. However, mutation analysis of all known SRNS genes is time and cost intensive. This report describes a new high-throughput method of mutation analysis using a PCR-based microfluidic technology that allows rapid simultaneous mutation analysis of 21 single-gene causes of SRNS in a large number of individuals. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This study screened individuals with SRNS; samples were submitted for mutation analysis from international sources between 1996 and 2012. For proof of principle, a pilot cohort of 48 individuals who harbored known mutations in known SRNS genes was evaluated. After improvements to the method, 48 individuals with an unknown cause of SRNS were then examined in a subsequent diagnostic study. The analysis included 16 recessive SRNS genes and 5 dominant SRNS genes. A 10-fold primer multiplexing was applied, allowing PCR-based amplification of 474 amplicons in 21 genes for 48 DNA samples simultaneously. Forty-eight individuals were indexed in a barcode PCR, and high-throughput sequencing was performed. All disease-causing variants were confirmed via Sanger sequencing. RESULTS The pilot study identified the genetic cause of disease in 42 of 48 (87.5%) of the affected individuals. The diagnostic study detected the genetic cause of disease in 16 of 48 (33%) of the affected individuals with a previously unknown cause of SRNS. Seven novel disease-causing mutations in PLCE1 (n=5), NPHS1 (n=1), and LAMB2 (n=1) were identified in <3 weeks. Use of this method could reduce costs to 1/29th of the cost of Sanger sequencing. CONCLUSION This highly parallel approach allows rapid (<3 weeks) mutation analysis of 21 genes known to cause SRNS at a greatly reduced cost (1/29th) compared with traditional mutation analysis techniques. It detects mutations in about 33% of childhood-onset SRNS cases.
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Affiliation(s)
- Svjetlana Lovric
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Humphrey Fang
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Virginia Vega-Warner
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan
| | - Carolin E Sadowski
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Heon Yung Gee
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Jan Halbritter
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Shazia Ashraf
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Pawaree Saisawat
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan
| | - Neveen A Soliman
- Department of Pediatrics, Center of Pediatric Nephrology & Transplantation, Kasr Al Ainy School of Medicine, Cairo University and Egyptian Group of Orphan Diseases, Cairo, Egypt
| | - Jameela A Kari
- Department of Pediatrics, King Abdulaziz University Hospital, Jeddah, Saudi Arabia; and
| | - Edgar A Otto
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan
| | - Friedhelm Hildebrandt
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; Howard Hughes Medical Institute, Chevy Chase, Maryland
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Sethi S, Glassock RJ, Fervenza FC. Focal segmental glomerulosclerosis: towards a better understanding for the practicing nephrologist. Nephrol Dial Transplant 2014; 30:375-84. [PMID: 24589721 DOI: 10.1093/ndt/gfu035] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Focal and segmental glomerulosclerosis (FSGS) is a common histopathological lesion that can represent a primary podocytopathy, or occur as an adaptive phenomenon consequent to nephron mass reduction, a scar from a healing vasculitic lesion, direct drug toxicity or viral infection among other secondary causes. Thus, the presence of an FSGS lesion in a renal biopsy does not confer a disease diagnosis, but rather represents the beginning of an exploratory process, hopefully leading ultimately to identification of a specific etiology and its appropriate treatment. We define primary FSGS as a 'primary' podocytopathy characterized clinically by the presence of nephrotic syndrome in a patient with an FSGS lesion on light microscopy and widespread foot process effacement on electron microscopy (EM). Secondary FSGS is commonly characterized by the absence of nephrotic syndrome and the presence of segmental foot process effacement on EM. Failure to accurately differentiate between the primary and secondary forms of FSGS has resulted in many patients undergoing unnecessary immunosuppressive treatment. Here, we review some key points that may assist the practicing nephrologist to distinguish between primary and secondary FSGS.
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Affiliation(s)
- Sanjeev Sethi
- Division of Anatomic Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | | | - Fernando C Fervenza
- Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, MN, USA
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Laurin LP, Lu M, Mottl AK, Blyth ER, Poulton CJ, Weck KE. Podocyte-associated gene mutation screening in a heterogeneous cohort of patients with sporadic focal segmental glomerulosclerosis. Nephrol Dial Transplant 2014; 29:2062-9. [DOI: 10.1093/ndt/gft532] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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Mahfuz I, Darling T, Wilkins S, White S, Cheng W. New insights into the pathogenesis of bladder exstrophy-epispadias complex. J Pediatr Urol 2013; 9:996-1005. [PMID: 23743131 DOI: 10.1016/j.jpurol.2013.05.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 05/01/2013] [Indexed: 02/02/2023]
Abstract
Bladder exstrophy-epispadias complex (BEEC) is a complex and debilitating congenital disease. Familial and twin studies suggest a possible genetic component in BEEC pathogenesis. Bladder mesenchyme (detrusor) development requires induction by a signal from bladder urothelium, and we and others have shown the Shh-Gli-Bmp4 signalling pathway is likely to be involved. P63 is a master regulator in epithelial stratification and is expressed in urothelium. We have shown that p63 knock-out mice undergo excessive urothelial apoptosis. Failure of mesenchymal induction by epithelium leads to BEEC. We further demonstrated that insertion/deletion (in/del) polymorphisms (1 base pair (bp) ins and 4 bp ins., and 12 bp del) in the ΔNP63 promoter reduce transcriptional efficiency, and are associated with a statistically significant increase in the risk of BEEC in humans. Furthermore, a Genome-Wide Expression Profiling (GWEP) study suggests possible involvement of PERP in human BEEC. Intriguingly, PERP is a direct target of p63 during development, and is also involved in epithelial stratification. PERP co-localizes with desmosome, and both PERP and desmosome are essential for maintaining tissue integrity by cellular adhesion and epithelial stratification. A recent study showed that PERP and desmosome expression levels are abnormal in human BEEC patients. This review describes the role of the P63 > PERP > desmosome pathway in the development of human bladder during embryogenesis. We hypothesize that disruption of this pathway may increase the risk of BEEC.
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Affiliation(s)
- Istiak Mahfuz
- Monash Institute of Medical Research, Faculty of Medicine, Nursing and Health Sciences, Monash University, Australia
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Urinary IgG and α2-macroglobulin are powerful predictors of outcome and responsiveness to steroids and cyclophosphamide in idiopathic focal segmental glomerulosclerosis with nephrotic syndrome. BIOMED RESEARCH INTERNATIONAL 2013; 2013:941831. [PMID: 24093110 PMCID: PMC3777177 DOI: 10.1155/2013/941831] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 07/10/2013] [Accepted: 08/04/2013] [Indexed: 11/17/2022]
Abstract
Objective. To assess whether high-molecular-weight proteins excretion predicts outcome and therapy-responsiveness in patients with FSGS and nephrotic syndrome. Research Design and Methods. Thirty-eight patients measured at biopsy fractional excretion of IgG (FEIgG) and urinary α2-macroglobulin/creatinine ratio (α2m/C). Low and high risk groups were defined by cutoffs assessed by ROC analysis. In all patients first-line therapy was with steroids alone or in combination with cyclophosphamide. Results. α2m/C and FEIgG were correlated with segmental sclerosis (r = 0.546; r = 0.522). Twenty-three patients (61%) entered Remission and 9 (24%) progressed to ESRD. Comparing low and high risk groups, by univariate analysis remission was predicted by FEIgG (77% versus 25%, P = 0.016) and α2m/C (81% versus 17%, P = 0.007) and ESRD at best by FEIgG (0% versus 75%, P < 0.0001) and α2m/C (4% versus 67%, P < 0.0001). By multivariate analysis FEIgG was the only independent predictor of remission and α2m/C the most powerful predictor of ESRD. Low and high risk groups of FEIgG and α2m/C in combination had very high predictive value of sustained remission and ESRD in response to therapy. Conclusions. FEIgG and α2m/C are powerful predictors of outcome and responsiveness to steroids and cyclophosphamide; their predictive value, if validated in prospective studies, may be useful in clinical practice suggesting first-line alternative treatments in high risk patients.
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Abstract
Renal biopsy was introduced in the 1950s. By 1980 the pathologic diagnostic criteria for the majority of medical kidney diseases known today, including pediatric diseases, were established using light, electron microscopy and immunohistochemistry. However, it has become clear that there are limitations in the morphologic evaluation, mainly because a given pattern of injury can be caused by different aetiologies and, conversely, a single aetiology may present with more than one histological pattern. An explosion in kidney disease research in the last 20-30 years has brought new knowledge from bench to bedside rapidly and resulted in new molecular and genetic tools that enhance the diagnostic and prognostic power of the renal biopsy. Genomic technologies such as polymerase chain reaction (PCR), in situ hybridization and oligonucleotide microarrays, collectively known as genomics, detect single or multiple genes underscoring the pathologic changes and revealing specific causes of injury that may require different treatment. The aims of this review are to (1) summarize current recommendations for diagnostic renal biopsies encompassing light microscopy, immunofluorescence or immunohistochemistry and electron microscopy; (2) address the limitations of morphology; (3) show current contributions of genomic technologies adjunct to the renal biopsy, and provide examples of how these may transform pathologic interpretation into molecular disease phenotypes.
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43
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Fervenza FC. A patient with nephrotic-range proteinuria and focal global glomerulosclerosis. Clin J Am Soc Nephrol 2013; 8:1979-87. [PMID: 23886564 DOI: 10.2215/cjn.03400313] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A young male is evaluated for nephrotic-range proteinuria, hypercalciuria, and an elevated serum creatinine. A renal biopsy is performed and shows focal global glomerulosclerosis. The absence of nephrotic syndrome suggest that glomerulosclerosis was a secondary process. Further analysis of the proteinuria showed it to be due mainly to low-molecular weight proteins. The case illustrates the crucial role of electron microscopy as well as evaluation of the identity of the proteinuria that accompanies a biopsy finding of focal and global or focal and segmental glomerulosclerosis.
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Affiliation(s)
- Fernando C Fervenza
- Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota
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Abstract
Our understanding of the pathogenesis of most primary glomerular diseases, including IgA nephropathy, membranous nephropathy and focal segmental glomerulosclerosis, is limited. Advances in molecular technology now permit genome-wide, high-throughput characterization of genes and gene products from biological samples. Comprehensive examinations of the genome, transcriptome, proteome and metabolome (collectively known as omics analyses), have been applied to the study of IgA nephropathy, membranous nephropathy and focal segmental glomerulosclerosis in both animal models and human patients. However, most omics studies of primary glomerular diseases, with the exception of large genomic studies, have been limited by inadequate sample sizes and the lack of kidney-specific data sets derived from kidney biopsy samples. Collaborative efforts to develop a standardized approach for prospective recruitment of patients, scheduled monitoring of clinical outcomes, and protocols for sampling of kidney tissues will be instrumental in uncovering the mechanisms that drive these diseases. Integration of molecular data sets with the results of clinical and histopathological studies will ultimately enable these diseases to be characterized in a comprehensive and systematic manner, and is expected to improve the diagnosis and treatment of these diseases.
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Kushiyama T, Oda T, Yamamoto K, Higashi K, Watanabe A, Takechi H, Uchida T, Oshima N, Sakurai Y, Miura S, Kumagai H. Protective effects of Rho kinase inhibitor fasudil on rats with chronic kidney disease. Am J Physiol Renal Physiol 2013; 304:F1325-34. [DOI: 10.1152/ajprenal.00447.2012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The protective effects of Rho kinase inhibitor fasudil against renal diseases have recently been reported. We compared the therapeutic effects of fasudil on the spontaneously hypercholesterolemic (SHC) rat, a model of chronic kidney disease (CKD) with proteinuria, with those of the angiotensin receptor blocker olmesartan (OL) by paying attention to the proteinuria and the macrophage phenotype. SHC rats were allocated to six treatment groups: a vehicle (Ve) group, a low-dose fasudil (FL) group, a high-dose fasudil (FH) group, an OL group, a combination of low-dose fasudil and OL (CL) group, and a combination of high-dose fasudil and OL (CH) group. Sprague-Dawley rats treated with vehicle served as a control ( n = 7/each). The rats were treated for 24 wk. Compared with the Ve group, proteinuria was significantly decreased in the FH, OL, and CL groups, and it completely disappeared in the CH group. Glomerular stainings of nephrin and F-actin were focally impaired in the Ve group but were restored in the CH group. Western blotting showed that the CH group had significantly increased renal nephrin expression compared with the Ve group. Interstitial infiltration of macrophages was significantly increased in the Ve group, which was significantly attenuated in all treatment groups. The ratio of CD206 (M2 macrophage marker) to CD68 mRNA was significantly greater in the CH group than in the Ve group. These results indicate that fasudil with OL reduces proteinuria by protecting podocyte integrity and alters the interstitial macrophage density/phenotype, thereby exerting renoprotective effects against CKD.
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Affiliation(s)
| | - Takashi Oda
- Department of Nephrology, National Defense Medical College, Saitama, Japan
| | - Kojiro Yamamoto
- Department of Nephrology, National Defense Medical College, Saitama, Japan
| | - Keishi Higashi
- Department of Nephrology, National Defense Medical College, Saitama, Japan
| | - Atsushi Watanabe
- Department of Nephrology, National Defense Medical College, Saitama, Japan
| | - Hanako Takechi
- Department of Nephrology, National Defense Medical College, Saitama, Japan
| | - Takahiro Uchida
- Department of Nephrology, National Defense Medical College, Saitama, Japan
| | - Naoki Oshima
- Department of Nephrology, National Defense Medical College, Saitama, Japan
| | - Yutaka Sakurai
- Department of Preventive Medicine and Public Health, National Defense Medical College, Saitama, Japan; and
| | - Soichiro Miura
- Department of Gastroenterology, National Defense Medical College, Saitama, Japan
| | - Hiroo Kumagai
- Department of Nephrology, National Defense Medical College, Saitama, Japan
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Esposito T, Lea RA, Maher BH, Moses D, Cox HC, Magliocca S, Angius A, Nyholt DR, Titus T, Kay T, Gray NA, Rastaldi MP, Parnham A, Gianfrancesco F, Griffiths LR. Unique X-linked familial FSGS with co-segregating heart block disorder is associated with a mutation in the NXF5 gene. Hum Mol Genet 2013; 22:3654-66. [PMID: 23686279 DOI: 10.1093/hmg/ddt215] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Focal segmental glomerulosclerosis (FSGS) is the consequence of a disease process that attacks the kidney's filtering system, causing serious scarring. More than half of FSGS patients develop chronic kidney failure within 10 years, ultimately requiring dialysis or renal transplantation. There are currently several genes known to cause the hereditary forms of FSGS (ACTN4, TRPC6, CD2AP, INF2, MYO1E and NPHS2). This study involves a large, unique, multigenerational Australian pedigree in which FSGS co-segregates with progressive heart block with apparent X-linked recessive inheritance. Through a classical combined approach of linkage and haplotype analysis, we identified a 21.19 cM interval implicated on the X chromosome. We then used a whole exome sequencing approach to identify two mutated genes, NXF5 and ALG13, which are located within this linkage interval. The two mutations NXF5-R113W and ALG13-T141L segregated perfectly with the disease phenotype in the pedigree and were not found in a large healthy control cohort. Analysis using bioinformatics tools predicted the R113W mutation in the NXF5 gene to be deleterious and cellular studies support a role in the stability and localization of the protein suggesting a causative role of this mutation in these co-morbid disorders. Further studies are now required to determine the functional consequence of these novel mutations to development of FSGS and heart block in this pedigree and to determine whether these mutations have implications for more common forms of these diseases in the general population.
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Affiliation(s)
- Teresa Esposito
- Institute of Genetics and Biophysics Adriano Buzzati-Traverso, National Research Council of Italy, Naples, Italy
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47
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Lipska BS, Balasz-Chmielewska I, Morzuch L, Wasielewski K, Vetter D, Borzecka H, Drozdz D, Firszt-Adamczyk A, Gacka E, Jarmolinski T, Ksiazek J, Kuzma-Mroczkowska E, Litwin M, Medynska A, Silska M, Szczepanska M, Tkaczyk M, Wasilewska A, Schaefer F, Zurowska A, Limon J. Mutational analysis in podocin-associated hereditary nephrotic syndrome in Polish patients: founder effect in the Kashubian population. J Appl Genet 2013; 54:327-33. [PMID: 23645318 PMCID: PMC3721000 DOI: 10.1007/s13353-013-0147-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 03/22/2013] [Accepted: 03/27/2013] [Indexed: 01/18/2023]
Abstract
Hereditary nephrotic syndrome is caused by mutations in a number of different genes, the most common being NPHS2. The aim of the study was to identify the spectrum of NPHS2 mutations in Polish patients with the disease. A total of 141 children with steroid-resistant nephrotic syndrome (SRNS) were enrolled in the study. Mutational analysis included the entire coding sequence and intron boundaries of the NPHS2 gene. Restriction fragment length polymorphism (RFLP) and TaqMan genotyping assay were applied to detect selected NPHS2 sequence variants in 575 population-matched controls. Twenty patients (14 %) had homozygous or compound heterozygous NPHS2 mutations, the most frequent being c.1032delT found in 11 children and p.R138Q found in four patients. Carriers of the c.1032delT allele were exclusively found in the Pomeranian (Kashubian) region, suggesting a founder effect origin. The 14 % NPHS2 gene mutation detection rate is similar to that observed in other populations. The heterogeneity of mutations detected in the studied group confirms the requirement of genetic testing the entire NPHS2 coding sequence in Polish patients, with the exception of Kashubs, who should be initially screened for the c.1032delT deletion.
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Affiliation(s)
- Beata S Lipska
- Department of Biology and Genetics, Medical University of Gdansk, Debinki str. 1, 80211, Gdansk, Poland.
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48
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Littman MP, Wiley CA, Raducha MG, Henthorn PS. Glomerulopathy and mutations in NPHS1 and KIRREL2 in soft-coated Wheaten Terrier dogs. Mamm Genome 2013; 24:119-26. [PMID: 23325127 DOI: 10.1007/s00335-012-9445-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 12/10/2012] [Indexed: 02/08/2023]
Abstract
Dogs of the soft-coated wheaten terrier breed (SCWT) are predisposed to adult-onset, genetically complex, protein-losing nephropathy (average onset age = 6.3 ± 2.0 years). A genome-wide association study using 62 dogs revealed a chromosomal region containing three statistically significant SNPs (p(raw) ≤ 4.13 × 10(-8); p(genome) ≤ 0.005) when comparing DNA samples from affected and geriatric (≥14 years) unaffected SCWTs. Sequencing of candidate genes in the region revealed single nucleotide changes in each of two closely linked genes, NPHS1 and KIRREL2, which encode the slit diaphragm proteins nephrin and Neph3/filtrin, respectively. In humans, mutations in nephrin and decreased expression of Neph3 are associated with podocytopathy and protein-losing nephropathy. The base substitutions change a glycine to arginine in the fibronectin type 3 domain of nephrin and a proline to arginine in a conserved proline-rich region in Neph3. These novel mutations are not described in other species, nor were they found in 550 dogs of 105 other breeds, except in 3 dogs, including an affected Airedale terrier, homozygous for both substitutions. Risk for nephropathy is highest in dogs homozygous for the mutations (OR = 9.06; 95 % CI = 4.24-19.35). This is the first molecular characterization of an inherited podocytopathy in dogs and may serve as a model for continued studies of complex genetic and environmental interactions in glomerular disease.
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Affiliation(s)
- Meryl P Littman
- Department of Clinical Studies, University of Pennsylvania School of Veterinary Medicine-Philadelphia, Philadelphia, PA 19104-6010, USA.
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Won KJ, Lee KP, Kim DK, Jung SH, Lee CK, Lee DH, Yu SY, Park SH, Lee HM, Kim B. Monoclonal Antibody against a-Actinin 4 from Human Umbilical Vein Endothelial Cells Inhibits Endothelium-Dependent Vasorelaxation. J Vasc Res 2013; 50:210-20. [DOI: 10.1159/000350588] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 03/06/2013] [Indexed: 11/19/2022] Open
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Mok KW, Mruk DD, Silvestrini B, Cheng CY. rpS6 Regulates blood-testis barrier dynamics by affecting F-actin organization and protein recruitment. Endocrinology 2012; 153:5036-48. [PMID: 22948214 PMCID: PMC3512016 DOI: 10.1210/en.2012-1665] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
During spermatogenesis, preleptotene spermatocytes residing near the basement membrane of the seminiferous tubule must traverse the blood-testis barrier (BTB) at stage VIII-IX of the epithelial cycle to continue their development in the adluminal compartment. Unlike other blood-tissue barriers (e.g. the blood-brain barrier) that are created by the endothelial tight junction (TJ) barrier of capillaries, the BTB is created by specialized junctions between Sertoli cells in which TJ coexists with basal ectoplasmic specialization (basal ES, a testis-specific adherens junction). The basal ES is typified by the presence of tightly packed actin filament bundles sandwiched between cisternae of endoplasmic reticulum and the apposing plasma membranes of Sertoli cells. These actin filament bundles also confer unusual adhesive strength to the BTB. Yet the mechanisms by which these filamentous actin (F-actin) networks are regulated from the bundled to the debundled state to facilitate the transit of spermatocytes remain elusive. Herein, we provide evidence that ribosomal protein S6 (rpS6), the downstream signaling molecule of the mammalian target of rapamycin complex 1 (mTORC1) pathway, is a major regulator of F-actin organization and adhesion protein recruitment at the BTB. rpS6 is restrictively and spatiotemporally activated at the BTB during the epithelial cycle. An activation of rpS6 led to a disruption of the Sertoli cell TJ barrier and BTB integrity. Its silencing in vitro or in vivo by using small interfering RNA duplexes or short hairpin RNA was found to promote the Sertoli cell TJ permeability barrier by the recruitment of adhesion proteins (e.g. claudin-11 and occludin) to the BTB. Thus, rpS6 in the mTORC1 pathway regulates BTB restructuring via its effects on the F-actin organization and protein recruitment at the BTB.
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Affiliation(s)
- Ka-Wai Mok
- Center for Biomedical Research, Population Council, New York, New York 10065, USA
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