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Clair G, Soloyan H, Cravedi P, Angeletti A, Salem F, Al-Rabadi L, De Filippo RE, Da Sacco S, Lemley KV, Sedrakyan S, Perin L. The spatially resolved transcriptome signatures of glomeruli in chronic kidney disease. JCI Insight 2024; 9:e165515. [PMID: 38516889 PMCID: PMC11063942 DOI: 10.1172/jci.insight.165515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 02/14/2024] [Indexed: 03/23/2024] Open
Abstract
Here, we used digital spatial profiling (DSP) to describe the glomerular transcriptomic signatures that may characterize the complex molecular mechanisms underlying progressive kidney disease in Alport syndrome, focal segmental glomerulosclerosis, and membranous nephropathy. Our results revealed significant transcriptional heterogeneity among diseased glomeruli, and this analysis showed that histologically similar glomeruli manifested different transcriptional profiles. Using glomerular pathology scores to establish an axis of progression, we identified molecular pathways with progressively decreased expression in response to increasing pathology scores, including signal recognition particle-dependent cotranslational protein targeting to membrane and selenocysteine synthesis pathways. We also identified a distinct signature of upregulated and downregulated genes common to all the diseases investigated when compared with nondiseased tissue from nephrectomies. These analyses using DSP at the single-glomerulus level could help to increase insight into the pathophysiology of kidney disease and possibly the identification of biomarkers of disease progression in glomerulopathies.
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Affiliation(s)
- Geremy Clair
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Hasmik Soloyan
- The GOFARR Laboratory, The Saban Research Institute, Division of Urology, Children’s Hospital Los Angeles, Los Angeles, California, USA
| | - Paolo Cravedi
- Department of Medicine, Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Andrea Angeletti
- Nephrology Dialysis and Renal Transplantation, IRCCS Istituto Giannina Gaslini, Genova, Italy
| | - Fadi Salem
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Jacksonville, Florida, USA
| | - Laith Al-Rabadi
- Division of Nephrology and Hypertension, Department of Internal Medicine, University of Utah Health, Salt Lake City, Utah, USA
| | - Roger E. De Filippo
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
- Department of Urology, Keck School of Medicine, and
| | - Stefano Da Sacco
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
- Department of Urology, Keck School of Medicine, and
| | - Kevin V. Lemley
- Division of Nephrology, Department of Pediatrics, University of Southern California, Los Angeles, California, USA
| | - Sargis Sedrakyan
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
- Department of Urology, Keck School of Medicine, and
| | - Laura Perin
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
- Department of Urology, Keck School of Medicine, and
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Dissanayake LV, Kravtsova O, Lowe M, McCrorey MK, Van Beusecum JP, Palygin O, Staruschenko A. The presence of xanthine dehydrogenase is crucial for the maturation of the rat kidneys. Clin Sci (Lond) 2024; 138:269-288. [PMID: 38358003 DOI: 10.1042/cs20231144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 01/24/2024] [Accepted: 02/14/2024] [Indexed: 02/16/2024]
Abstract
The development of the kidney involves essential cellular processes, such as cell proliferation and differentiation, which are led by interactions between multiple signaling pathways. Xanthine dehydrogenase (XDH) catalyzes the reaction producing uric acid in the purine catabolism, which plays a multifaceted role in cellular metabolism. Our previous study revealed that the genetic ablation of the Xdh gene in rats leads to smaller kidneys, kidney damage, decline of renal functions, and failure to thrive. Rats, unlike humans, continue their kidney development postnatally. Therefore, we explored whether XDH plays a critical role in kidney development using SS-/- rats during postnatal development phase. XDH expression was significantly increased from postnatal day 5 to 15 in wild-type but not homozygote rat kidneys. The transcriptomic profile of renal tissue revealed several dysregulated pathways due to the lack of Xdh expression with the remodeling in inflammasome, purinergic signaling, and redox homeostasis. Further analysis suggested that lack of Xdh affects kidney development, likely via dysregulation of epidermal growth factor and its downstream STAT3 signaling. The present study showed that Xdh is essential for kidney maturation. Our data, alongside the previous research, suggests that loss of Xdh function leads to developmental issues, rendering them vulnerable to kidney diseases in adulthood.
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Affiliation(s)
- Lashodya V Dissanayake
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida; Tampa, FL 33602, U.S.A
| | - Olha Kravtsova
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida; Tampa, FL 33602, U.S.A
| | - Melissa Lowe
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida; Tampa, FL 33602, U.S.A
| | - Marice K McCrorey
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC 29425, U.S.A
| | - Justin P Van Beusecum
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC 29425, U.S.A
- Ralph H. Johnson Veterans Affairs Healthcare System, Charleston, SC 29403, U.S.A
| | - Oleg Palygin
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC 29425, U.S.A
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425, U.S.A
| | - Alexander Staruschenko
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida; Tampa, FL 33602, U.S.A
- Hypertension and Kidney Research Center, University of South Florida, Tampa, FL 33602, U.S.A
- James A. Haley Veterans' Hospital, Tampa, FL 33612, U.S.A
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Madison J, Wilhelm K, Meehan DT, Gratton MA, Vosik D, Samuelson G, Ott M, Fascianella J, Nelson N, Cosgrove D. Ramipril therapy in integrin α1-null, autosomal recessive Alport mice triples lifespan: mechanistic clues from RNA-seq analysis. J Pathol 2024; 262:296-309. [PMID: 38129319 PMCID: PMC10872630 DOI: 10.1002/path.6231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 10/10/2023] [Accepted: 10/29/2023] [Indexed: 12/23/2023]
Abstract
The standard of care for patients with Alport syndrome (AS) is angiotensin-converting enzyme (ACE) inhibitors. In autosomal recessive Alport (ARAS) mice, ACE inhibitors double lifespan. We previously showed that deletion of Itga1 in Alport mice [double-knockout (DKO) mice] increased lifespan by 50%. This effect seemed dependent on the prevention of laminin 211-mediated podocyte injury. Here, we treated DKO mice with vehicle or ramipril starting at 4 weeks of age. Proteinuria and glomerular filtration rates were measured at 5-week intervals. Glomeruli were analyzed for laminin 211 deposition in the glomerular basement membrane (GBM) and GBM ultrastructure was analyzed using transmission electron microscopy (TEM). RNA sequencing (RNA-seq) was performed on isolated glomeruli at all time points and the results were compared with cultured podocytes overlaid (or not) with recombinant laminin 211. Glomerular filtration rate declined in ramipril-treated DKO mice between 30 and 35 weeks. Proteinuria followed these same patterns with normalization of foot process architecture in ramipril-treated DKO mice. RNA-seq revealed a decline in the expression of Foxc2, nephrin (Nphs1), and podocin (Nphs2) mRNAs, which was delayed in the ramipril-treated DKO mice. GBM accumulation of laminin 211 was delayed in ramipril-treated DKO mice, likely due to a role for α1β1 integrin in CDC42 activation in Alport mesangial cells, which is required for mesangial filopodial invasion of the subendothelial spaces of the glomerular capillary loops. Ramipril synergized with Itga1 knockout, tripling lifespan compared with untreated ARAS mice. © 2023 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Affiliation(s)
- Jacob Madison
- Boys Town National Research Hospital, Omaha, NE, USA
| | - Kevin Wilhelm
- Boys Town National Research Hospital, Omaha, NE, USA
| | | | | | - Denise Vosik
- Boys Town National Research Hospital, Omaha, NE, USA
| | | | - Megan Ott
- Boys Town National Research Hospital, Omaha, NE, USA
| | | | - Noa Nelson
- Boys Town National Research Hospital, Omaha, NE, USA
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Deltas C, Papagregoriou G, Louka SF, Malatras A, Flinter F, Gale DP, Gear S, Gross O, Hoefele J, Lennon R, Miner JH, Renieri A, Savige J, Turner AN. Genetic Modifiers of Mendelian Monogenic Collagen IV Nephropathies in Humans and Mice. Genes (Basel) 2023; 14:1686. [PMID: 37761826 PMCID: PMC10530214 DOI: 10.3390/genes14091686] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/09/2023] [Accepted: 08/17/2023] [Indexed: 09/29/2023] Open
Abstract
Familial hematuria is a clinical sign of a genetically heterogeneous group of conditions, accompanied by broad inter- and intrafamilial variable expressivity. The most frequent condition is caused by pathogenic (or likely pathogenic) variants in the collagen-IV genes, COL4A3/A4/A5. Pathogenic variants in COL4A5 are responsible for the severe X-linked glomerulopathy, Alport syndrome (AS), while homozygous or compound heterozygous variants in the COL4A3 or the COL4A4 gene cause autosomal recessive AS. AS usually leads to progressive kidney failure before the age of 40-years when left untreated. People who inherit heterozygous COL4A3/A4 variants are at-risk of a slowly progressive form of the disease, starting with microscopic hematuria in early childhood, developing Alport spectrum nephropathy. Sometimes, they are diagnosed with benign familial hematuria, and sometimes with autosomal dominant AS. At diagnosis, they often show thin basement membrane nephropathy, reflecting the uniform thin glomerular basement membrane lesion, inherited as an autosomal dominant condition. On a long follow-up, most patients will retain normal or mildly affected kidney function, while a substantial proportion will develop chronic kidney disease (CKD), even kidney failure at an average age of 55-years. A question that remains unanswered is how to distinguish those patients with AS or with heterozygous COL4A3/A4 variants who will manifest a more aggressive kidney function decline, requiring prompt medical intervention. The hypothesis that a subgroup of patients coinherit additional genetic modifiers that exacerbate their clinical course has been investigated by several researchers. Here, we review all publications that describe the potential role of candidate genetic modifiers in patients and include a summary of studies in AS mouse models.
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Affiliation(s)
- Constantinos Deltas
- School of Medicine, University of Cyprus, Nicosia 2109, Cyprus
- biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, Nicosia 2109, Cyprus
| | - Gregory Papagregoriou
- biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, Nicosia 2109, Cyprus
| | - Stavroula F. Louka
- biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, Nicosia 2109, Cyprus
| | - Apostolos Malatras
- biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, Nicosia 2109, Cyprus
| | - Frances Flinter
- Clinical Genetics Department, Guy’s & St Thomas’ NHS Foundation Trust, London SE1 9RT, UK
| | - Daniel P. Gale
- Department of Renal Medicine, University College London, London NW3 2PF, UK
| | | | - Oliver Gross
- Clinic for Nephrology and Rheumatology, University Medicine Goettingen, 37075 Goettingen, Germany
| | - Julia Hoefele
- Institute of Human Genetics, Klinikum Rechts der Isar, School of Medicine & Health, Technical University Munich, 81675 Munich, Germany
| | - Rachel Lennon
- Wellcome Centre for Cell-Matrix Research, University of Manchester, Manchester M13 9WU, UK
| | - Jeffrey H. Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Alessandra Renieri
- Medical Genetics, University of Siena, 53100 Siena, Italy
- Med Biotech Hub and Competence Center, Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy
- Genetica Medica, Azienda Ospedaliero-Universitaria Senese, 53100 Siena, Italy
| | - Judy Savige
- Department of Medicine (Melbourne Health and Northern Health), The University of Melbourne, Parkville, VIC 3052, Australia
| | - A. Neil Turner
- Renal Medicine, Royal Infirmary, University of Edinburgh, Edinburgh EH16 4UX, UK
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Madison J, Wilhelm K, Meehan DT, Delimont D, Samuelson G, Cosgrove D. Glomerular basement membrane deposition of collagen α1(III) in Alport glomeruli by mesangial filopodia injures podocytes via aberrant signaling through DDR1 and integrin α2β1. J Pathol 2022; 258:26-37. [PMID: 35607980 PMCID: PMC9378723 DOI: 10.1002/path.5969] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/29/2022] [Accepted: 05/20/2022] [Indexed: 11/20/2022]
Abstract
In Alport mice, activation of the endothelin A receptor (ETA R) in mesangial cells results in sub-endothelial invasion of glomerular capillaries by mesangial filopodia. Filopodia deposit mesangial matrix in the glomerular basement membrane (GBM), including laminin 211 which activates NF-κB, resulting in induction of inflammatory cytokines. Herein we show that collagen α1(III) is also deposited in the GBM. Collagen α1(III) localized to the mesangium in wild-type mice and was found in both the mesangium and the GBM in Alport mice. We show that collagen α1(III) activates discoidin domain receptor family, member 1 (DDR1) receptors both in vitro and in vivo. To elucidate whether collagen α1(III) might cause podocyte injury, cultured murine Alport podocytes were overlaid with recombinant collagen α1(III), or not, for 24 h and RNA was analyzed by RNA sequencing (RNA-seq). These same cells were subjected to siRNA knockdown for integrin α2 or DDR1 and the RNA was analyzed by RNA-seq. Results were validated in vivo using RNA-seq from RNA isolated from wild-type and Alport mouse glomeruli. Numerous genes associated with podocyte injury were up- or down-regulated in both Alport glomeruli and cultured podocytes treated with collagen α1(III), 18 of which have been associated previously with podocyte injury or glomerulonephritis. The data indicate α2β1 integrin/DDR1 co-receptor signaling as the dominant regulatory mechanism. This may explain earlier studies where deletion of either DDR1 or α2β1 integrin in Alport mice ameliorates renal pathology. © 2022 Boys Town National Research Hospital. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Sasaki H, Sasaki N. Tensin 2-deficient nephropathy - mechanosensitive nephropathy, genetic susceptibility. Exp Anim 2022; 71:252-263. [PMID: 35444113 PMCID: PMC9388341 DOI: 10.1538/expanim.22-0031] [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] [Indexed: 11/30/2022] Open
Abstract
Tensin 2 (TNS2), a focal adhesion protein, is considered to anchor focal adhesion proteins to β integrin as an integrin adaptor protein and/or serve as a scaffold to facilitate the
interactions of these proteins. In the kidney, TNS2 localizes to the basolateral surface of glomerular epithelial cells, i.e., podocytes. Loss of TNS2 leads to the development of glomerular
basement membrane lesions and abnormal accumulation of extracellular matrix in maturing glomeruli during the early postnatal stages. It subsequently results in podocyte foot process
effacement, eventually leading to glomerulosclerosis. Histopathological features of the affected glomeruli in the middle stage of the disease include expansion of the mesangial matrix
without mesangial cell proliferation. In this review, we provide an overview of TNS2-deficient nephropathy and discuss the potential mechanism underlying this mechanosensitive nephropathy,
which may be applicable to other glomerulonephropathies, such as CD151-deficient nephropathy and Alport syndrome. The onset of TNS2-deficient nephropathy strictly depends on the genetic
background, indicating the presence of critical modifier genes. A better understanding of molecular mechanisms of mechanosensitive nephropathy may open new avenues for the management of
patients with glomerulonephropathies.
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Affiliation(s)
- Hayato Sasaki
- Laboratory of Laboratory Animal Science and Medicine, School of Veterinary Medicine, Kitasato University
| | - Nobuya Sasaki
- Laboratory of Laboratory Animal Science and Medicine, School of Veterinary Medicine, Kitasato University
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Cosgrove D, Madison J. Molecular and Cellular Mechanisms Underlying the Initiation and Progression of Alport Glomerular Pathology. Front Med (Lausanne) 2022; 9:846152. [PMID: 35223933 PMCID: PMC8863674 DOI: 10.3389/fmed.2022.846152] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 01/17/2022] [Indexed: 01/11/2023] Open
Abstract
Alport syndrome results from a myriad of variants in the COL4A3, COL4A4, or COL4A5 genes that encode type IV (basement membrane) collagens. Unlike type IV collagen α1(IV)2α2(IV)1 heterotrimers, which are ubiquitous in basement membranes, α3/α4/α5 have a limited tissue distribution. The absence of these basement membrane networks causes pathologies in some, but not all these tissues. Primarily the kidney glomerulus, the stria vascularis of the inner ear, the lens, and the retina as well as a rare link with aortic aneurisms. Defects in the glomerular basement membranes results in delayed onset and progressive focal segmental glomerulosclerosis ultimately requiring the patient to undergo dialysis and if accessible, kidney transplant. The lifespan of patients with Alport syndrome is ultimately significantly shortened. This review addresses the consequences of the altered glomerular basement membrane composition in Alport syndrome with specific emphasis on the mechanisms underlying initiation and progression of glomerular pathology.
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Affiliation(s)
| | - Jacob Madison
- Boys Town National Research Hospital, Omaha, NE, United States
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Rubel D, Boulanger J, Craciun F, Xu EY, Zhang Y, Phillips L, Callahan M, Weber W, Song W, Ngai N, Bukanov NO, Shi X, Hariri A, Husson H, Ibraghimov-Beskrovnaya O, Liu S, Gross O. Anti-microRNA-21 Therapy on Top of ACE Inhibition Delays Renal Failure in Alport Syndrome Mouse Models. Cells 2022; 11:cells11040594. [PMID: 35203245 PMCID: PMC8869926 DOI: 10.3390/cells11040594] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 01/28/2022] [Accepted: 02/03/2022] [Indexed: 02/01/2023] Open
Abstract
Col4a3−/− Alport mice serve as an animal model for renal fibrosis. MicroRNA-21 (miR-21) expression has been shown to be increased in the kidneys of Alport syndrome patients. Here, we investigated the nephroprotective effects of Lademirsen anti-miR-21 therapy. We used a fast-progressing Col4a3−/− mouse model with a 129/SvJ background and an intermediate-progressing F1 hybrid mouse model with a mixed genetic background, with angiotensin-converting enzyme inhibitor (ACEi) monotherapy in combination with anti-miR-21 therapy. In the fast-progressing model, the anti miR-21 and ACEi therapies showed an additive effect in the reduction in fibrosis, the decline of proteinuria, the preservation of kidney function and increased survival. In the intermediate-progressing F1 model, the anti-miR-21 and ACEi therapies individually improved kidney pathology. Both also improved kidney function and survival; however, the combination showed a significant additive effect, particularly for survival. RNA sequencing (RNA-seq) gene expression profiling revealed that the anti-miR-21 and ACEi therapies modulate several common pathways. However, anti-miR-21 was particularly effective at normalizing the expression profiles of the genes involved in renal tubulointerstitial injury pathways. In conclusion, significant additive effects were detected for the combination of anti-miR-21 and ACEi therapies on kidney function, pathology and survival in Alport mouse models, as well as a strong differential effect of anti-miR-21 on the renal expression of fibrotic factors. These results support the addition of anti-miR-21 to the current standard of care (ACEi) in ongoing clinical trials in patients with Alport syndrome.
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Affiliation(s)
- Diana Rubel
- Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany; (D.R.); (Y.Z.)
| | | | - Florin Craciun
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
| | - Ethan Y. Xu
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
- Excision BioTherapeutics, San Francisco, CA 94111, USA
| | - Yanqin Zhang
- Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany; (D.R.); (Y.Z.)
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Lucy Phillips
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
- Abbvie Bioresearch Center, Worcester, MA 01605, USA
| | - Michelle Callahan
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
| | - William Weber
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
- Takeda Pharmaceuticals, Cambridge, MA 02139, USA
| | - Wenping Song
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
| | - Nicholas Ngai
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
| | - Nikolay O. Bukanov
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
- Janssen Pharmaceuticals, Boston, MA 02115, USA
| | - Xingyi Shi
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
- Novartis Institute for BioMedical Research, Boston, MA 02139, USA
| | - Ali Hariri
- Sanofi-Genzyme, Clinical Development, Cambridge, MA 02142, USA; (A.H.); (S.L.)
- Eloxx Pharmaceuticals, Watertown, MA 02140, USA
| | - Hervé Husson
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
| | - Oxana Ibraghimov-Beskrovnaya
- Sanofi-Genzyme Research and Development, Framingham, MA 02118, USA; (F.C.); (E.Y.X.); (L.P.); (M.C.); (W.W.); (W.S.); (N.N.); (N.O.B.); (X.S.); (H.H.); (O.I.-B.)
- Dyne Therapeutics, Waltham, MA 02451, USA
| | - Shiguang Liu
- Sanofi-Genzyme, Clinical Development, Cambridge, MA 02142, USA; (A.H.); (S.L.)
| | - Oliver Gross
- Clinic for Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany; (D.R.); (Y.Z.)
- Correspondence: ; Tel.: +49-551-39-60488
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Jandl K, Mutgan AC, Eller K, Schaefer L, Kwapiszewska G. The basement membrane in the cross-roads between the lung and kidney. Matrix Biol 2021; 105:31-52. [PMID: 34839001 DOI: 10.1016/j.matbio.2021.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 11/05/2021] [Accepted: 11/18/2021] [Indexed: 12/23/2022]
Abstract
The basement membrane (BM) is a specialized layer of extracellular matrix components that plays a central role in maintaining lung and kidney functions. Although the composition of the BM is usually tissue specific, the lung and the kidney preferentially use similar BM components. Unsurprisingly, diseases with BM defects often have severe pulmonary or renal manifestations, sometimes both. Excessive remodeling of the BM, which is a hallmark of both inflammatory and fibrosing diseases in the lung and the kidney, can lead to the release of BM-derived matrikines, proteolytic fragments with distinct biological functions. These matrikines can then influence disease activity at the site of liberation. However, they are also released to the circulation, where they can directly affect the vascular endothelium or target other organs, leading to extrapulmonary or extrarenal manifestations. In this review, we will summarize the current knowledge of the composition and function of the BM and its matrikines in health and disease, both in the lung and in the kidney. By comparison, we will highlight, why the BM and its matrikines may be central in establishing a renal-pulmonary interaction axis.
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Affiliation(s)
- Katharina Jandl
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria; Otto Loewi Research Center, Department of Pharmacology, Medical University of Graz, Graz, Austria
| | - Ayse Ceren Mutgan
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria; Otto Loewi Research Center, Department of Physiology, Medical University of Graz, Graz, Austria
| | - Kathrin Eller
- Clinical Division of Nephrology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - Liliana Schaefer
- Institute of Pharmacology and Toxicology, Goethe University, Frankfurt, Germany
| | - Grazyna Kwapiszewska
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria; Otto Loewi Research Center, Department of Physiology, Medical University of Graz, Graz, Austria; Institute for Lung Health (ILH), Giessen, Germany..
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Single, Double and Triple Blockade of RAAS in Alport Syndrome: Different Tools to Freeze the Evolution of the Disease. J Clin Med 2021; 10:jcm10214946. [PMID: 34768466 PMCID: PMC8584724 DOI: 10.3390/jcm10214946] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/17/2021] [Accepted: 10/20/2021] [Indexed: 12/29/2022] Open
Abstract
Background: The goal of the treatment of Alport syndrome (AS) is to delay the progression of kidney damage. The current standard of care is the use of Renin Angiotensin Aldosterone System (RAAS) blockers: angiotensin-converting enzyme inhibition (ACEi), angiotensin receptor blockade, and, recently, spironolactone (SP). Aim of the study: the purpose of this retrospective study is to evaluate the efficacy (reduction of proteinuria and changes of glomerular function) and safety of a sequential introduction of RAAS blockers up to a triple RAAS blockade in pediatric proteinuric patients with AS. Methods: in this retrospective study (1995 to 2019), we evaluated proteinuria values in AS patients, during the 12 months following the beginning of a new RAAS blocker, up to a triple blockade. ACEi was always the first line of treatment; then ARB and SP were sequentially added if uPCR increased by 50% from the basal level in 2 consecutive samples during a 3-months observation period, or when uPCR ratio was >2 mg/mg. Results: 26 patients (mean age at treatment onset was 10.55 ± 5.02 years) were enrolled. All patients were on ACEi, 14/26 were started on a second drug (6/14 ARB, 8/14 SP) after a mean time of 2.2 ± 1.7 years, 7/26 were on triple RAAS blockade after a further period of 5.5 ± 2.3 years from the introduction of a second drug. Repeated Measure Anova analysis of log-transformed data shows that the reduction of uPCR values after Time 0 from the introduction of the first, second and third drug is highly significant in all three cases (p values = 0.0016, 0.003, and 0.014, respectively). No significant changes in eGFR were recorded in any group, apart from a 15-year-old boy with X-linked AS, who developed kidney failure. One patient developed mild hyperkaliemia, and one gynecomastia and symptomatic hypotension. No life-threatening events were recorded. Conclusions: double and triple RAAS blockade is an effective and safe strategy to reduce proteinuria in children with AS. Nevertheless, we suggest monitoring eGFR and Kaliemia during follow-up.
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11
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Namba M, Kobayashi T, Kohno M, Koyano T, Hirose T, Fukushima M, Matsuyama M. Creation of X-linked Alport syndrome rat model with Col4a5 deficiency. Sci Rep 2021; 11:20836. [PMID: 34675305 PMCID: PMC8531394 DOI: 10.1038/s41598-021-00354-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 10/12/2021] [Indexed: 12/31/2022] Open
Abstract
Alport syndrome is an inherited chronic human kidney disease, characterized by glomerular basement membrane abnormalities. This disease is caused by mutations in COL4A3, COL4A4, or COL4A5 gene. The knockout mice for Col4α3, Col4α4, and Col4α5 are developed and well characterized for the study of Alport syndrome. However, disease progression and effects of pharmacological therapy depend on the genetic variability. This model was reliable only to mouse. In this study, we created a novel Alport syndrome rat model utilizing the rGONAD technology, which generated rat with a deletion of the Col4α5 gene. Col4α5 deficient rats showed hematuria, proteinuria, high levels of BUN, Cre, and then died at 18 to 28 weeks of age (Hemizygous mutant males). Histological and ultrastructural analyses displayed the abnormalities including parietal cell hyperplasia, mesangial sclerosis, and interstitial fibrosis. Then, we demonstrated that α3/α4/α5 (IV) and α5/α5/α6 (IV) chains of type IV collagen disrupted in Col4α5 deficient rats. Thus, Col4α5 mutant rat is a reliable candidate for the Alport syndrome model for underlying the mechanism of kidney diseases and further identifying potential therapeutic targets for human renal diseases.
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Affiliation(s)
- Masumi Namba
- Division of Molecular Genetics, Shigei Medical Research Institute, 2117 Yamada, Minami-ku, Okayama, 701-0202, Japan
| | - Tomoe Kobayashi
- Division of Molecular Genetics, Shigei Medical Research Institute, 2117 Yamada, Minami-ku, Okayama, 701-0202, Japan
| | - Mayumi Kohno
- Division of Molecular Genetics, Shigei Medical Research Institute, 2117 Yamada, Minami-ku, Okayama, 701-0202, Japan
| | - Takayuki Koyano
- Division of Molecular Genetics, Shigei Medical Research Institute, 2117 Yamada, Minami-ku, Okayama, 701-0202, Japan
| | - Takuo Hirose
- Division of Nephrology and Endocrinology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan.,Department of Endocrinology and Applied Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masaki Fukushima
- Division of Molecular Genetics, Shigei Medical Research Institute, 2117 Yamada, Minami-ku, Okayama, 701-0202, Japan.,Shigei Medical Research Hospital, Okayama, Japan
| | - Makoto Matsuyama
- Division of Molecular Genetics, Shigei Medical Research Institute, 2117 Yamada, Minami-ku, Okayama, 701-0202, Japan.
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12
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Stenvinkel P, Chertow GM, Devarajan P, Levin A, Andreoli SP, Bangalore S, Warady BA. Chronic Inflammation in Chronic Kidney Disease Progression: Role of Nrf2. Kidney Int Rep 2021; 6:1775-1787. [PMID: 34307974 PMCID: PMC8258499 DOI: 10.1016/j.ekir.2021.04.023] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/13/2021] [Accepted: 04/19/2021] [Indexed: 12/16/2022] Open
Abstract
Despite recent advances in the management of chronic kidney disease (CKD), morbidity and mortality rates in these patients remain high. Although pressure-mediated injury is a well-recognized mechanism of disease progression in CKD, emerging data indicate that an intermediate phenotype involving chronic inflammation, oxidative stress, hypoxia, senescence, and mitochondrial dysfunction plays a key role in the etiology, progression, and pathophysiology of CKD. A variety of factors promote chronic inflammation in CKD, including oxidative stress and the adoption of a proinflammatory phenotype by resident kidney cells. Regulation of proinflammatory and anti-inflammatory factors through NF-κB- and nuclear factor, erythroid 2 like 2 (Nrf2)-mediated gene transcription, respectively, plays a critical role in the glomerular and tubular cell response to kidney injury. Chronic inflammation contributes to the decline in glomerular filtration rate (GFR) in CKD. Whereas the role of chronic inflammation in diabetic kidney disease (DKD) has been well-elucidated, there is now substantial evidence indicating unresolved inflammatory processes lead to fibrosis and eventual end-stage kidney disease (ESKD) in several other diseases, such as Alport syndrome, autosomal-dominant polycystic kidney disease (ADPKD), IgA nephropathy (IgAN), and focal segmental glomerulosclerosis (FSGS). In this review, we aim to clarify the mechanisms of chronic inflammation in the pathophysiology and disease progression across the spectrum of kidney diseases, with a focus on Nrf2.
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Affiliation(s)
- Peter Stenvinkel
- Department of Renal Medicine M99, Karolinska University Hospital at Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Glenn M Chertow
- Division of Nephrology, Stanford University, Stanford, California, USA
| | - Prasad Devarajan
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, USA
| | - Adeera Levin
- Department of Medicine, The University of British Columbia, Vancouver, Canada
| | - Sharon P Andreoli
- Department of Pediatrics, Indiana University School of Medicine, Indiana University, Indianapolis, Indiana, USA
| | - Sripal Bangalore
- Division of Cardiology, New York University, New York, New York, USA
| | - Bradley A Warady
- Division of Pediatric Nephrology, Children's Mercy Kansas City, Kansas City, Missouri, USA
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13
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Quinlan C, Rheault MN. Genetic Basis of Type IV Collagen Disorders of the Kidney. Clin J Am Soc Nephrol 2021; 16:1101-1109. [PMID: 33849932 PMCID: PMC8425620 DOI: 10.2215/cjn.19171220] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The glomerular basement membrane is a vital component of the filtration barrier of the kidney and is primarily composed of a highly structured matrix of type IV collagen. Specific isoforms of type IV collagen, the α3(IV), α4(IV), and α5(IV) isoforms, assemble into trimers that are required for normal glomerular basement membrane function. Disruption or alteration in these isoforms leads to breakdown of the glomerular basement membrane structure and function and can lead to progressive CKD known as Alport syndrome. However, there is wide variability in phenotype among patients with mutations affecting type IV collagen that depends on a complex interplay of sex, genotype, and X-chromosome inactivation. This article reviews the genetic basis of collagen disorders of the kidney as well as potential treatments for these conditions, including direct alteration of the DNA, RNA therapies, and manipulation of collagen proteins.
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Affiliation(s)
- Catherine Quinlan
- Department of Nephrology, Royal Children’s Hospital, Melbourne, Victoria, Australia,Department of Kidney Regeneration, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Michelle N. Rheault
- Division of Pediatric Nephrology, Department of Pediatrics, University of Minnesota Masonic Children’s Hospital, Minneapolis, Minnesota
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14
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Li L, Li H, Wang L, Bu T, Liu S, Mao B, Cheng CY. A local regulatory network in the testis mediated by laminin and collagen fragments that supports spermatogenesis. Crit Rev Biochem Mol Biol 2021; 56:236-254. [PMID: 33761828 DOI: 10.1080/10409238.2021.1901255] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
It is almost five decades since the discovery of the hypothalamic-pituitary-testicular axis. This refers to the hormonal axis that connects the hypothalamus, pituitary gland and testes, which in turn, regulates the production of spermatozoa through spermatogenesis in the seminiferous tubules, and testosterone through steroidogenesis by Leydig cells in the interstitium, of the testes. Emerging evidence has demonstrated the presence of a regulatory network across the seminiferous epithelium utilizing bioactive molecules produced locally at specific domains of the epithelium. Studies have shown that biologically active fragments are produced from structural laminin and collagen chains in the basement membrane. Additionally, bioactive peptides are also produced locally in non-basement membrane laminin chains at the Sertoli-spermatid interface known as apical ectoplasmic specialization (apical ES, a testis-specific actin-based anchoring junction type). These bioactive peptides are derived from structural laminins and/or collagens at the corresponding sites through proteolytic cleavage by matrix metalloproteinases (MMPs). They in turn serve as autocrine and/or paracrine factors to modulate and coordinate cellular events across the epithelium by linking the apical and basal compartments, the apical and basal ES, the blood-testis barrier (BTB), and the basement membrane of the tunica propria. The cellular events supported by these bioactive peptides/fragments include the release of spermatozoa at spermiation, remodeling of the immunological barrier to facilitate the transport of preleptotene spermatocytes across the BTB, and the transport of haploid spermatids across the epithelium to support spermiogenesis. In this review, we critically evaluate these findings. Our goal is to identify research areas that deserve attentions in future years. The proposed research also provides the much needed understanding on the biology of spermatogenesis supported by a local network of regulatory biomolecules.
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Affiliation(s)
- Linxi Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Huitao Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Lingling Wang
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Tiao Bu
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China
| | - Shiwen Liu
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Baiping Mao
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - C Yan Cheng
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
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15
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Parchem JG, Kanasaki K, Lee SB, Kanasaki M, Yang JL, Xu Y, Earl KM, Keuls RA, Gattone VH, Kalluri R. STOX1 deficiency is associated with renin-mediated gestational hypertension and placental defects. JCI Insight 2021; 6:141588. [PMID: 33301424 PMCID: PMC7934881 DOI: 10.1172/jci.insight.141588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 12/03/2020] [Indexed: 11/17/2022] Open
Abstract
The pathogenesis of preeclampsia and other hypertensive disorders of pregnancy remains poorly defined despite the substantial burden of maternal and neonatal morbidity associated with these conditions. In particular, the role of genetic variants as determinants of disease susceptibility is understudied. Storkhead-box protein 1 (STOX1) was first identified as a preeclampsia risk gene through family-based genetic linkage studies in which loss-of-function variants were proposed to underlie increased preeclampsia susceptibility. We generated a genetic Stox1 loss-of-function mouse model (Stox1 KO) to evaluate whether STOX1 regulates blood pressure in pregnancy. Pregnant Stox1-KO mice developed gestational hypertension evidenced by a significant increase in blood pressure compared with WT by E17.5. While severe renal, placental, or fetal growth abnormalities were not observed, the Stox1-KO phenotype was associated with placental vascular and extracellular matrix abnormalities. Mechanistically, we found that gestational hypertension in Stox1-KO mice resulted from activation of the uteroplacental renin-angiotensin system. This mechanism was supported by showing that treatment of pregnant Stox1-KO mice with an angiotensin II receptor blocker rescued the phenotype. Our study demonstrates the utility of genetic mouse models for uncovering links between genetic variants and effector pathways implicated in the pathogenesis of hypertensive disorders of pregnancy.
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Affiliation(s)
- Jacqueline G Parchem
- Department of Cancer Biology, Metastasis Research Center, University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Department of Obstetrics, Gynecology and Reproductive Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Texas, USA
| | - Keizo Kanasaki
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Soo Bong Lee
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Megumi Kanasaki
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Joyce L Yang
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Yong Xu
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Kadeshia M Earl
- Department of Cancer Biology, Metastasis Research Center, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Rachel A Keuls
- Development, Disease Models & Therapeutics Graduate Program, Center for Cell and Gene Therapy, and Stem Cells and Regenerative Medicine Center, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Vincent H Gattone
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Raghu Kalluri
- Department of Cancer Biology, Metastasis Research Center, University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
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16
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Abstract
The glomerular basement membrane (GBM) is a key component of the glomerular capillary wall and is essential for kidney filtration. The major components of the GBM include laminins, type IV collagen, nidogens and heparan sulfate proteoglycans. In addition, the GBM harbours a number of other structural and regulatory components and provides a reservoir for growth factors. New technologies have improved our ability to study the composition and assembly of basement membranes. We now know that the GBM is a complex macromolecular structure that undergoes key transitions during glomerular development. Defects in GBM components are associated with a range of hereditary human diseases such as Alport syndrome, which is caused by defects in the genes COL4A3, COL4A4 and COL4A5, and Pierson syndrome, which is caused by variants in LAMB2. In addition, the GBM is affected by acquired autoimmune disorders and metabolic diseases such as diabetes mellitus. Current treatments for diseases associated with GBM involvement aim to reduce intraglomerular pressure and to treat the underlying cause where possible. As our understanding about the maintenance and turnover of the GBM improves, therapies to replace GBM components or to stimulate GBM repair could translate into new therapies for patients with GBM-associated disease.
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17
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Basement membrane collagens and disease mechanisms. Essays Biochem 2019; 63:297-312. [PMID: 31387942 PMCID: PMC6744580 DOI: 10.1042/ebc20180071] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 07/09/2019] [Accepted: 07/22/2019] [Indexed: 12/28/2022]
Abstract
Basement membranes (BMs) are specialised extracellular matrix (ECM) structures and collagens are a key component required for BM function. While collagen IV is the major BM collagen, collagens VI, VII, XV, XVII and XVIII are also present. Mutations in these collagens cause rare multi-systemic diseases but these collagens have also been associated with major common diseases including stroke. Developing treatments for these conditions will require a collective effort to increase our fundamental understanding of the biology of these collagens and the mechanisms by which mutations therein cause disease. Novel insights into pathomolecular disease mechanisms and cellular responses to these mutations has been exploited to develop proof-of-concept treatment strategies in animal models. Combined, these studies have also highlighted the complexity of the disease mechanisms and the need to obtain a more complete understanding of these mechanisms. The identification of pathomolecular mechanisms of collagen mutations shared between different disorders represent an attractive prospect for treatments that may be effective across phenotypically distinct disorders.
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18
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Bülow RD, Boor P. Extracellular Matrix in Kidney Fibrosis: More Than Just a Scaffold. J Histochem Cytochem 2019; 67:643-661. [PMID: 31116062 DOI: 10.1369/0022155419849388] [Citation(s) in RCA: 175] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Kidney fibrosis is the common histological end-point of progressive, chronic kidney diseases (CKDs) regardless of the underlying etiology. The hallmark of renal fibrosis, similar to all other organs, is pathological deposition of extracellular matrix (ECM). Renal ECM is a complex network of collagens, elastin, and several glycoproteins and proteoglycans forming basal membranes and interstitial space. Several ECM functions beyond providing a scaffold and organ stability are being increasingly recognized, for example, in inflammation. ECM composition is determined by the function of each of the histological compartments of the kidney, that is, glomeruli, tubulo-interstitium, and vessels. Renal ECM is a dynamic structure undergoing remodeling, particularly during fibrosis. From a clinical perspective, ECM proteins are directly involved in several rare renal diseases and indirectly in CKD progression during renal fibrosis. ECM proteins could serve as specific non-invasive biomarkers of fibrosis and scaffolds in regenerative medicine. The gold standard and currently only specific means to measure renal fibrosis is renal biopsy, but new diagnostic approaches are appearing. Here, we discuss the localization, function, and remodeling of major renal ECM components in healthy and diseased, fibrotic kidneys and the potential use of ECM in diagnostics of renal fibrosis and in tissue engineering.
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Affiliation(s)
- Roman David Bülow
- Institute of Pathology, RWTH Aachen University Hospital, Aachen, Germany
| | - Peter Boor
- Institute of Pathology, RWTH Aachen University Hospital, Aachen, Germany.,Department of Nephrology and Immunology, RWTH Aachen University Hospital, Aachen, Germany
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19
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van Roeyen CRC, Martin IV, Drescher A, Schuett KA, Hermert D, Raffetseder U, Otten S, Buhl EM, Braun GS, Kuppe C, Liehn E, Boor P, Weiskirchen R, Eriksson U, Gross O, Eitner F, Floege J, Ostendorf T. Identification of platelet-derived growth factor C as a mediator of both renal fibrosis and hypertension. Kidney Int 2019; 95:1103-1119. [PMID: 30827511 DOI: 10.1016/j.kint.2018.11.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 11/15/2018] [Accepted: 11/21/2018] [Indexed: 02/06/2023]
Abstract
Platelet-derived growth factors (PDGF) have been implicated in kidney disease progression. We previously found that PDGF-C is upregulated at sites of renal fibrosis and that antagonism of PDGF-C reduces fibrosis in the unilateral ureteral obstruction model. We studied the role of PDGF-C in collagen 4A3-/- ("Alport") mice, a model of progressive renal fibrosis with greater relevance to human kidney disease. Alport mice were crossbred with PDGF-C-/- mice or administered a neutralizing PDGF-C antibody. Both PDGF-C deficiency and neutralization reduced serum creatinine and blood urea nitrogen levels and mitigated glomerular injury, renal fibrosis, and renal inflammation. Unexpectedly, systolic blood pressure was also reduced in both Alport and wild-type mice treated with a neutralizing PDGF-C antibody. Neutralization of PDGF-C reduced arterial wall thickness in the renal cortex of Alport mice. Aortic rings isolated from anti-PDGF-C-treated wildtype mice exhibited reduced tension and faster relaxation than those of untreated mice. In vitro, PDGF-C upregulated angiotensinogen in aortic tissue and in primary hepatocytes and induced nuclear factor κB (NFκB)/p65-binding to the angiotensinogen promoter in hepatocytes. Neutralization of PDGF-C suppressed transcript expression of angiotensinogen in Alport mice and angiotensin II receptor type 1 in Alport and wildtype mice. Finally, administration of neutralizing PDGF-C antibodies ameliorated angiotensin II-induced hypertension in healthy mice. Thus, in addition to its key role in mediating renal fibrosis, we identified PDGF-C as a mediator of hypertension via effects on renal vasculature and on the renin-angiotensin system. The contribution to both renal fibrosis and hypertension render PDGF-C an attractive target in progressive kidney disease.
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Affiliation(s)
- Claudia R C van Roeyen
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany.
| | - Ina V Martin
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Ana Drescher
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | | | - Daniela Hermert
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Ute Raffetseder
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Stephanie Otten
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Eva M Buhl
- Institute of Pathology, RWTH Aachen University, Aachen, Germany
| | - Gerald S Braun
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Christoph Kuppe
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Elisa Liehn
- Institute for Molecular Cardiovascular Research, RWTH Aachen University, Aachen, Germany
| | - Peter Boor
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany; Institute of Pathology, RWTH Aachen University, Aachen, Germany
| | - Ralf Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry RWTH Aachen University, Aachen, Germany
| | - Ulf Eriksson
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Oliver Gross
- Division of Nephrology and Rheumatology, University Medicine Göttingen, Göttingen, Germany
| | - Frank Eitner
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany; Kidney Diseases Research, Bayer AG, Wuppertal, Germany
| | - Jürgen Floege
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
| | - Tammo Ostendorf
- Division of Nephrology and Clinical Immunology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
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20
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Parchem JG, Kanasaki K, Kanasaki M, Sugimoto H, Xie L, Hamano Y, Lee SB, Gattone VH, Parry S, Strauss JF, Garovic VD, McElrath TF, Lu KH, Sibai BM, LeBleu VS, Carmeliet P, Kalluri R. Loss of placental growth factor ameliorates maternal hypertension and preeclampsia in mice. J Clin Invest 2018; 128:5008-5017. [PMID: 30179860 PMCID: PMC6205389 DOI: 10.1172/jci99026] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 08/28/2018] [Indexed: 12/28/2022] Open
Abstract
Preeclampsia remains a clinical challenge due to its poorly understood pathogenesis. A prevailing notion is that increased placental production of soluble fms-like tyrosine kinase-1 (sFlt-1) causes the maternal syndrome by inhibiting proangiogenic placental growth factor (PlGF) and VEGF. However, the significance of PlGF suppression in preeclampsia is uncertain. To test whether preeclampsia results from the imbalance of angiogenic factors reflected by an abnormal sFlt-1/PlGF ratio, we studied PlGF KO (Pgf-/-) mice and noted that the mice did not develop signs or sequelae of preeclampsia despite a marked elevation in circulating sFLT-1. Notably, PlGF KO mice had morphologically distinct placentas, showing an accumulation of junctional zone glycogen. We next considered the role of placental PlGF in an established model of preeclampsia (pregnant catechol-O-methyltransferase-deficient [COMT-deficient] mice) by generating mice with deletions in both the Pgf and Comt genes. Deletion of placental PlGF in the context of COMT loss resulted in a reduction in maternal blood pressure and increased placental glycogen, indicating that loss of PlGF might be protective against the development of preeclampsia. These results identify a role for PlGF in placental development and support a complex model for the pathogenesis of preeclampsia beyond an angiogenic factor imbalance.
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Affiliation(s)
- Jacqueline G Parchem
- Department of Cancer Biology, Metastasis Research Center, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- Department of Obstetrics, Gynecology and Reproductive Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas, USA
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas, USA
| | - Keizo Kanasaki
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Megumi Kanasaki
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Hikaru Sugimoto
- Department of Cancer Biology, Metastasis Research Center, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Liang Xie
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Yuki Hamano
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Soo Bong Lee
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Vincent H Gattone
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Samuel Parry
- Department of Obstetrics and Gynecology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jerome F Strauss
- Department of Obstetrics and Gynecology, Virginia Commonwealth University School of Medicine, Richmond, Virginia, USA
| | - Vesna D Garovic
- Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Thomas F McElrath
- Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Karen H Lu
- Department of Gynecologic Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Baha M Sibai
- Department of Obstetrics, Gynecology and Reproductive Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Valerie S LeBleu
- Department of Cancer Biology, Metastasis Research Center, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Peter Carmeliet
- Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, Katholieke Universiteit (KU) Leuven, Leuven, Belgium
- Laboratory of Angiogenesis and Vascular Metabolism, Vesalius Research Center, Center for Cancer Biology (CCB), Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Raghu Kalluri
- Department of Cancer Biology, Metastasis Research Center, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
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21
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Funk SD, Lin MH, Miner JH. Alport syndrome and Pierson syndrome: Diseases of the glomerular basement membrane. Matrix Biol 2018; 71-72:250-261. [PMID: 29673759 PMCID: PMC6146048 DOI: 10.1016/j.matbio.2018.04.008] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/13/2018] [Accepted: 04/13/2018] [Indexed: 12/17/2022]
Abstract
The glomerular basement membrane (GBM) is an important component of the kidney's glomerular filtration barrier. Like all basement membranes, the GBM contains type IV collagen, laminin, nidogen, and heparan sulfate proteoglycan. It is flanked by the podocytes and glomerular endothelial cells that both synthesize it and adhere to it. Mutations that affect the GBM's collagen α3α4α5(IV) components cause Alport syndrome (kidney disease with variable ear and eye defects) and its variants, including thin basement membrane nephropathy. Mutations in LAMB2 that impact the synthesis or function of laminin α5β2γ1 (LM-521) cause Pierson syndrome (congenital nephrotic syndrome with eye and neurological defects) and its less severe variants, including isolated congenital nephrotic syndrome. The very different types of kidney diseases that result from mutations in collagen IV vs. laminin are likely due to very different pathogenic mechanisms. A better understanding of these mechanisms should lead to targeted therapeutic approaches that can help people with these rare but important diseases.
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Affiliation(s)
- Steven D Funk
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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22
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Zhang H, Fredericks T, Xiong G, Qi Y, Rychahou PG, Li JD, Pihlajaniemi T, Xu W, Xu R. Membrane associated collagen XIII promotes cancer metastasis and enhances anoikis resistance. Breast Cancer Res 2018; 20:116. [PMID: 30285809 PMCID: PMC6167877 DOI: 10.1186/s13058-018-1030-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 07/25/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Increased collagen expression and deposition are associated with cancer progression and poor prognosis in breast cancer patients. However, function and regulation of membrane-associated collagen in breast cancer have not been determined. Collagen XIII is a type II transmembrane protein within the collagen superfamily. Experiments in tissue culture and knockout mouse models show that collagen XIII is involved in cell adhesion and differentiation of certain cell types. In the present study, we determined roles of collagen XIII in breast cancer progression and metastasis. METHODS We analyzed the association of collagen XIII expression with breast cancer development and metastasis using published gene expression profiles generated from human breast cancer tissues. Utilizing gain- and loss- of function approaches and 3D culture assays, we investigated roles of collagen XIII in regulating invasive tumor growth. Using the tumorsphere/mammosphere formation assay and the detachment cell culture assay, we determined whether collagen XIII enhances cancer cell stemness and induces anoikis resistance. We also inhibited collagen XIII signaling with β1 integrin function-blocking antibody. Finally, using the lung colonization assay and the orthotopic mammary tumor model, we investigated roles of collagen XIII in regulating breast cancer colonization and metastasis. Cox proportional hazard (log-rank) test, two-sided Student's t-test (two groups) and one-way ANOVA (three or more groups) analyses were used in this study. RESULTS Collagen XIII expression is significantly higher in human breast cancer tissue compared with normal mammary gland. Increased collagen XIII mRNA levels in breast cancer tissue correlated with short distant recurrence free survival. We showed that collagen XIII expression promoted invasive tumor growth in 3D culture, enhanced cancer cell stemness, and induced anoikis resistance. Collagen XIII expression induced β1 integrin activation. Blocking β1 integrin activation significantly reduced collagen XIII-induced invasion and mammosphere formation. Importantly, silencing collagen XIII in MDA-MB-231 cells reduced lung colonization and metastasis. CONCLUSIONS Our results demonstrate a novel function of collagen XIII in promoting cancer metastasis, cell invasion, and anoikis resistance.
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Affiliation(s)
- Hui Zhang
- Department of Laboratory Medicine, The First Hospital of Jilin University, Changchun, 130021, Jilin Province, China.,UK Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA
| | - Tricia Fredericks
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Kentucky, Lexington, KY, 40504, USA
| | - Gaofeng Xiong
- UK Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA
| | - Yifei Qi
- UK Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA
| | - Piotr G Rychahou
- Department of Surgery, College of Medicine, University of Kentucky, Lexington, KY, 40504, USA
| | - Jia-Da Li
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, Hunan Province, China
| | - Taina Pihlajaniemi
- Center for Cell-Matrix Research and Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, 90014, Oulu, Finland
| | - Wei Xu
- Department of Laboratory Medicine, The First Hospital of Jilin University, Changchun, 130021, Jilin Province, China.
| | - Ren Xu
- UK Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA. .,Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, 40536, USA.
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23
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Abstract
The glomerular basement membrane (GBM) is a specialized structure with a significant role in maintaining the glomerular filtration barrier. This GBM is formed from the fusion of two basement membranes during development and its function in the filtration barrier is achieved by key extracellular matrix components including type IV collagen, laminins, nidogens, and heparan sulfate proteoglycans. The characteristics of specific matrix isoforms such as laminin-521 (α5β2γ1) and the α3α4α5 chain of type IV collagen are essential for the formation of a mature GBM and the restricted tissue distribution of these isoforms makes the GBM a unique structure. Detailed investigation of the GBM has been driven by the identification of inherited abnormalities in matrix proteins and the need to understand pathogenic mechanisms causing severe glomerular disease. A well-described hereditary GBM disease is Alport syndrome, associated with a progressive glomerular disease, hearing loss, and lens defects due to mutations in the genes COL4A3, COL4A4, or COL4A5. Other proteins associated with inherited diseases of the GBM include laminin β2 in Pierson syndrome and LMX1B in nail patella syndrome. The knowledge of these genetic mutations associated with GBM defects has enhanced our understanding of cell-matrix signaling pathways affected in glomerular disease. This review will address current knowledge of GBM-associated abnormalities and related signaling pathways, as well as discussing the advances toward disease-targeted therapies for patients with glomerular disease.
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Affiliation(s)
- Christine Chew
- Faculty of Biology Medicine and Health, Wellcome Trust Centre for Cell-Matrix Research, Division of Cell Matrix Biology, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Rachel Lennon
- Faculty of Biology Medicine and Health, Wellcome Trust Centre for Cell-Matrix Research, Division of Cell Matrix Biology, School of Biological Sciences, University of Manchester, Manchester, United Kingdom.,Department of Paediatric Nephrology, Royal Manchester Children's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
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24
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Funk SD, Bayer RH, Malone AF, McKee KK, Yurchenco PD, Miner JH. Pathogenicity of a Human Laminin β2 Mutation Revealed in Models of Alport Syndrome. J Am Soc Nephrol 2017; 29:949-960. [PMID: 29263159 DOI: 10.1681/asn.2017090997] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Accepted: 11/19/2017] [Indexed: 01/15/2023] Open
Abstract
Pierson syndrome is a congenital nephrotic syndrome with eye and neurologic defects caused by mutations in laminin β2 (LAMB2), a major component of the glomerular basement membrane (GBM). Pathogenic missense mutations in human LAMB2 cluster in or near the laminin amino-terminal (LN) domain, a domain required for extracellular polymerization of laminin trimers and basement membrane scaffolding. Here, we investigated an LN domain missense mutation, LAMB2-S80R, which was discovered in a patient with Pierson syndrome and unusually late onset of proteinuria. Biochemical data indicated that this mutation impairs laminin polymerization, which we hypothesized to be the cause of the patient's nephrotic syndrome. Testing this hypothesis in genetically altered mice showed that the corresponding amino acid change (LAMB2-S83R) alone is not pathogenic. However, expression of LAMB2-S83R significantly increased the rate of progression to kidney failure in a Col4a3-/- mouse model of autosomal recessive Alport syndrome and increased proteinuria in Col4a5+/- females that exhibit a mild form of X-linked Alport syndrome due to mosaic deposition of collagen α3α4α5(IV) in the GBM. Collectively, these data show the pathogenicity of LAMB2-S80R and provide the first evidence of genetic modification of Alport phenotypes by variation in another GBM component. This finding could help explain the wide range of Alport syndrome onset and severity observed in patients with Alport syndrome, even for family members who share the same COL4 mutation. Our results also show the complexities of using model organisms to investigate genetic variants suspected of being pathogenic in humans.
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Affiliation(s)
- Steven D Funk
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Raymond H Bayer
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Andrew F Malone
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Karen K McKee
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
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25
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Murine recombinant angiotensin-converting enzyme 2 attenuates kidney injury in experimental Alport syndrome. Kidney Int 2017; 91:1347-1361. [DOI: 10.1016/j.kint.2016.12.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 12/20/2016] [Accepted: 12/22/2016] [Indexed: 01/11/2023]
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26
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Abstract
In this commentary, I review recent advances in Alport syndrome genetics, diagnostics, and therapeutics. I also offer some opinions regarding strategies to optimize the early identification of affected individuals to promote early therapeutic intervention.
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Affiliation(s)
- Clifford Kashtan
- Department of Pediatrics, Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis, MN, USA
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27
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Clark SD, Nabity MB, Cianciolo RE, Dufek B, Cosgrove D. X-Linked Alport Dogs Demonstrate Mesangial Filopodial Invasion of the Capillary Tuft as an Early Event in Glomerular Damage. PLoS One 2016; 11:e0168343. [PMID: 27959966 PMCID: PMC5154607 DOI: 10.1371/journal.pone.0168343] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 11/29/2016] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND X-linked Alport syndrome (XLAS), caused by mutations in the type IV collagen COL4A5 gene, accounts for approximately 80% of human Alport syndrome. Dogs with XLAS have a similar clinical progression. Prior studies in autosomal recessive Alport mice demonstrated early mesangial cell invasion as the source of laminin 211 in the glomerular basement membrane (GBM), leading to proinflammatory signaling. The objective of this study was to verify this process in XLAS dogs. METHODS XLAS dogs and WT littermates were monitored with serial clinicopathologic data and kidney biopsies. Biopsies were obtained at set milestones defined by the onset of microalbuminuria (MA), overt proteinuria, onset of azotemia, moderate azotemia, and euthanasia. Kidney biopsies were analyzed by histopathology, immunohistochemistry, and electron microscopy. RESULTS XLAS dogs showed progressive decrease in renal function and progressive increase in interstitial fibrosis and glomerulosclerosis (based on light microscopy and immunostaining for fibronectin). The only identifiable structural abnormality at the time of microalbuminuria was ultrastructural evidence of mild segmental GBM multilamination, which was more extensive when overt proteinuria developed. Co-localization studies showed that mesangial laminin 211 and integrin α8β1 accumulated in the GBM at the onset of overt proteinuria and coincided with ultrastructural evidence of mild cellular interpositioning, consistent with invasion of the capillary loops by mesangial cell processes. CONCLUSION In a large animal model, the induction of mesangial filopodial invasion of the glomerular capillary loop leading to the irregular deposition of laminin 211 is an early initiating event in Alport glomerular pathology.
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Affiliation(s)
- Sabrina D. Clark
- Department of Veterinary Pathobiology, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America
- * E-mail:
| | - Mary B. Nabity
- Department of Veterinary Pathobiology, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America
| | - Rachel E. Cianciolo
- Department of Veterinary Biosciences, The Ohio State University Columbus, Ohio, United States of America
| | - Brianna Dufek
- Center for Basic Research, Boys Town National Research Hospital, Omaha, Nebraska, United States of America
| | - Dominic Cosgrove
- Center for Basic Research, Boys Town National Research Hospital, Omaha, Nebraska, United States of America
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28
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Abstract
Alport syndrome is the result of mutations in any of three type IV collagen genes, COL4A3, COL4A4, or COL4A5. Because the three collagen chains form heterotrimers, there is an absence of all three proteins in the basement membranes where they are expressed. In the glomerulus, the mature glomerular basement membrane type IV collagen network, normally comprised of two separate networks, α3(IV)/α4(IV)/α5(IV) and α1(IV)/α2(IV), is comprised entirely of collagen α1(IV)/α2. This review addresses the current state of our knowledge regarding the consequence of this change in basement membrane composition, including both the direct, via collagen receptor binding, and indirect, regarding influences on glomerular biomechanics. The state of our current understanding regarding mechanisms of glomerular disease initiation and progression will be examined, as will the current state of the art regarding emergent therapeutic approaches to slow or arrest glomerular disease in Alport patients.
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29
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Cosgrove D, Liu S. Collagen IV diseases: A focus on the glomerular basement membrane in Alport syndrome. Matrix Biol 2016; 57-58:45-54. [PMID: 27576055 DOI: 10.1016/j.matbio.2016.08.005] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 08/05/2016] [Accepted: 08/17/2016] [Indexed: 12/21/2022]
Abstract
Alport syndrome is the result of mutations in any of three type IV collagen genes, COL4A3, COL4A4, or COL4A5. Because the three collagen chains form heterotrimers, there is an absence of all three proteins in the basement membranes where they are expressed. In the glomerulus, the mature glomerular basement membrane type IV collagen network, normally comprised of two separate networks, α3(IV)/α4(IV)/α5(IV) and α1(IV)/α2(IV), is comprised entirely of collagen α1(IV)/α2. This review addresses the current state of our knowledge regarding the consequence of this change in basement membrane composition, including both the direct, via collagen receptor binding, and indirect, regarding influences on glomerular biomechanics. The state of our current understanding regarding mechanisms of glomerular disease initiation and progression will be examined, as will the current state of the art regarding emergent therapeutic approaches to slow or arrest glomerular disease in Alport patients.
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30
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Jarad G, Knutsen RH, Mecham RP, Miner JH. Albumin contributes to kidney disease progression in Alport syndrome. Am J Physiol Renal Physiol 2016; 311:F120-30. [PMID: 27147675 DOI: 10.1152/ajprenal.00456.2015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 04/29/2016] [Indexed: 12/31/2022] Open
Abstract
Alport syndrome is a familial kidney disease caused by defects in the collagen type IV network of the glomerular basement membrane. Lack of collagen-α3α4α5(IV) changes the glomerular basement membrane morphologically and functionally, rendering it leaky to albumin and other plasma proteins. Filtered albumin has been suggested to be a cause of the glomerular and tubular injuries observed at advanced stages of Alport syndrome. To directly investigate the role that albumin plays in the progression of disease in Alport syndrome, we generated albumin knockout (Alb(-/-)) mice to use as a tool for removing albuminuria as a component of kidney disease. Mice lacking albumin were healthy and indistinguishable from control littermates, although they developed hypertriglyceridemia. Dyslipidemia was observed in Alb(+/-) mice, which displayed half the normal plasma albumin concentration. Alb mutant mice were bred to collagen-α3(IV) knockout (Col4a3(-/-)) mice, which are a model for human Alport syndrome. Lack of circulating and filtered albumin in Col4a3(-/-);Alb(-/-) mice resulted in dramatically improved kidney disease outcomes, as these mice lived 64% longer than did Col4a3(-/-);Alb(+/+) and Col4a3(-/-);Alb(+/-) mice, despite similar blood pressures and serum triglyceride levels. Further investigations showed that the absence of albumin correlated with reduced transforming growth factor-β1 signaling as well as reduced tubulointerstitial, glomerular, and podocyte pathology. We conclude that filtered albumin is injurious to kidney cells in Alport syndrome and perhaps in other proteinuric kidney diseases, including diabetic nephropathy.
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Affiliation(s)
- George Jarad
- Division of Nephrology, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri; and
| | - Russell H Knutsen
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri
| | - Robert P Mecham
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri
| | - Jeffrey H Miner
- Division of Nephrology, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri; and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri
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31
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Endothelin A receptor activation on mesangial cells initiates Alport glomerular disease. Kidney Int 2016; 90:300-310. [PMID: 27165837 DOI: 10.1016/j.kint.2016.02.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 01/21/2016] [Accepted: 02/11/2016] [Indexed: 01/19/2023]
Abstract
Recent work demonstrates that Alport glomerular disease is mediated through a biomechanical strain-sensitive activation of mesangial actin dynamics. This occurs through a Rac1/CDC42 cross-talk mechanism that results in the invasion of the subcapillary spaces by mesangial filopodia. The filopodia deposit mesangial matrix proteins in the glomerular basement membrane, including laminin 211, which activates focal adhesion kinase in podocytes culminating in the up-regulation of proinflammatory cytokines and metalloproteinases. These events drive the progression of glomerulonephritis. Here we test whether endothelial cell-derived endothelin-1 is up-regulated in Alport glomeruli and further elevated by hypertension. Treatment of cultured mesangial cells with endothelin-1 activates the formation of drebrin-positive actin microspikes. These microspikes do not form when cells are treated with the endothelin A receptor antagonist sitaxentan or under conditions of small, interfering RNA knockdown of endothelin A receptor mRNA. Treatment of Alport mice with sitaxentan results in delayed onset of proteinuria, normalized glomerular basement membrane morphology, inhibition of mesangial filopodial invasion of the glomerular capillaries, normalization of glomerular expression of metalloproteinases and proinflammatory cytokines, increased life span, and prevention of glomerulosclerosis and interstitial fibrosis. Thus endothelin A receptor activation on mesangial cells is a key event in initiation of Alport glomerular disease in this model.
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32
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Savva I, Pierides A, Deltas C. RAAS inhibition and the course of Alport syndrome. Pharmacol Res 2016; 107:205-210. [PMID: 26995302 DOI: 10.1016/j.phrs.2016.03.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 03/04/2016] [Accepted: 03/14/2016] [Indexed: 12/26/2022]
Abstract
Alport syndrome (AS) is a hereditary progressive glomerulonephritis with a high life-time risk for end-stage renal disease (ESRD). Most patients will reach ESRD before the age of 30 years, while a subset of them with milder mutations will do so at older ages, even after 50 years. Frequent extrarenal manifestations are hearing loss and ocular abnormalities. AS is a genetically heterogeneous collagen IV nephropathy, with 85% of the cases caused by mutations in the X-linked COL4A5 gene and the rest by homozygous or compound heterozygous mutations in either the COL4A3 or the COL4A4 gene on chromosome 2q36-37. There is no radical cure for the disease and attempts to use various stem cell therapies in animal models have been met with ambiguous success. However, effective treatment has been accomplished with pharmacological intervention at the renin-angiotensin-aldosterone system (RAAS), first in animal models of AS and more recently in humans. Angiotensin converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) have been shown to significantly delay the progression of chronic kidney disease and the onset of ESRD. Also, renin inhibitors and aldosterone blockade were used with positive results, while the combination of ACEis and ARBs was met with mixed success. An important study, the EARLY-PROTECT, aims at evaluating the efficacy of ACEis when administered very early on in children with AS. Novel therapies are also tested experimentally or are under design in animal models by several groups, including the use of amniotic fluid stem cells and synthetic chaperones.
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Affiliation(s)
- Isavella Savva
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus
| | - Alkis Pierides
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus; Department of Nephrology, Hippocrateon Hospital, Nicosia, Cyprus
| | - Constantinos Deltas
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus.
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33
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Abstract
Collagens mediate essential hemostasis by maintaining the integrity and stability of the vascular wall. Imbalanced turnover of collagens by uncontrolled formation and/or degradation may result in pathologic conditions such as fibrosis. Thickening of the vessel wall because of accumulation of collagens may lead to arterial occlusion or thrombosis. Thinning of the wall because of collagen degradation or deficiency may lead to rupture of the vessel wall or aneurysm. Preventing excessive hemorrhage or thrombosis relies on collagen-mediated actions. Von Willebrand factor, integrins and glycoprotein VI, as well as clotting factors, can bind collagen to restore normal hemostasis after trauma. This review outlines the essential roles of collagens in mediating hemostasis, with a focus on collagens types I, III, IV, VI, XV, and XVIII.
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Affiliation(s)
| | - N G Kjeld
- Nordic Bioscience A/S, Herlev, Denmark
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34
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Zeisberg M, Zeisberg EM. Precision renal medicine: a roadmap towards targeted kidney fibrosis therapies. FIBROGENESIS & TISSUE REPAIR 2015; 8:16. [PMID: 26330891 PMCID: PMC4556008 DOI: 10.1186/s13069-015-0033-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 08/10/2015] [Indexed: 12/17/2022]
Abstract
Based on extensive pre-clinical achievements over the past decades, it appears to be due time for a successful clinical translation in the renal fibrosis field-but what is the quickest road to get there? In light of the recent launch of the Precision Medicine Initiative and success of molecularly informed drugs in oncology, we here discuss what it may take to bring molecularly targeted anti-fibrotic to clinical use in chronic progressive kidney disease.
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Affiliation(s)
- Michael Zeisberg
- />Department of Nephrology and Rheumatology, University Medical Center Göttingen, Georg August University, Robert Koch Str. 40, 37075 Göttingen, Germany
| | - Elisabeth M. Zeisberg
- />Department of Cardiology and Pneumology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
- />German Center for Cardiovascular Research (DZHK), Robert Koch Street 40, Göttingen, Germany
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35
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Sugahara G, Naito I, Miyagawa Y, Komiyama T, Takemura N, Kobayashi R, Mineshige T, Kamiie J, Shirota K. Pathological features of proteinuric nephropathy resembling Alport syndrome in a young Pyrenean Mountain dog. J Vet Med Sci 2015; 77:1175-8. [PMID: 25892536 PMCID: PMC4591163 DOI: 10.1292/jvms.15-0117] [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] [Indexed: 11/22/2022] Open
Abstract
The renal biopsy tissue from a 9-month-old, male Pyrenean Mountain dog with renal disorder and severe proteinuria was examined. Ultrastructural examination revealed multilaminar splitting and fragmentation of the glomerular basement membrane (GBM) and diffuse podocyte foot process effacement. Immunofluorescent staining for α(IV) chains revealed presence of α5(IV) and complete absence of α3(IV) and α4(IV) chains in the GBM. Immunohistochemistry also revealed decreased and altered expression of nephrin and podocin in the glomeruli compared with normal canine glomeruli. These results suggested that the glomerular disease of the present case might be consistent with canine hereditary nephropathy resembling human Alport syndrome caused by genetic defect of type IV collagen, and indicated possible contribution of podocyte injury to severe proteinuria in this case.
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Affiliation(s)
- Go Sugahara
- Laboratory of Veterinary Pathology, School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5201, Japan
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36
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Gross O, Perin L, Deltas C. Alport syndrome from bench to bedside: the potential of current treatment beyond RAAS blockade and the horizon of future therapies. Nephrol Dial Transplant 2014; 29 Suppl 4:iv124-30. [DOI: 10.1093/ndt/gfu028] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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38
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Delimont D, Dufek BM, Meehan DT, Zallocchi M, Gratton MA, Phillips G, Cosgrove D. Laminin α2-mediated focal adhesion kinase activation triggers Alport glomerular pathogenesis. PLoS One 2014; 9:e99083. [PMID: 24915008 PMCID: PMC4051676 DOI: 10.1371/journal.pone.0099083] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 05/09/2014] [Indexed: 01/16/2023] Open
Abstract
It has been known for some time that laminins containing α1 and α2 chains, which are normally restricted to the mesangial matrix, accumulate in the glomerular basement membranes (GBM) of Alport mice, dogs, and humans. We show that laminins containing the α2 chain, but not those containing the α1 chain activates focal adhesion kinase (FAK) on glomerular podocytes in vitro and in vivo. CD151-null mice, which have weakened podocyte adhesion to the GBM rendering these mice more susceptible to biomechanical strain in the glomerulus, also show progressive accumulation of α2 laminins in the GBM, and podocyte FAK activation. Analysis of glomerular mRNA from both models demonstrates significant induction of MMP-9, MMP-10, MMP-12, MMPs linked to GBM destruction in Alport disease models, as well as the pro-inflammatory cytokine IL-6. SiRNA knockdown of FAK in cultured podocytes significantly reduced expression of MMP-9, MMP-10 and IL-6, but not MMP-12. Treatment of Alport mice with TAE226, a small molecule inhibitor of FAK activation, ameliorated fibrosis and glomerulosclerosis, significantly reduced proteinuria and blood urea nitrogen levels, and partially restored GBM ultrastructure. Glomerular expression of MMP-9, MMP-10 and MMP-12 mRNAs was significantly reduced in TAE226 treated animals. Collectively, this work identifies laminin α2-mediated FAK activation in podocytes as an important early event in Alport glomerular pathogenesis and suggests that FAK inhibitors, if safe formulations can be developed, might be employed as a novel therapeutic approach for treating Alport renal disease in its early stages.
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Affiliation(s)
- Duane Delimont
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska, United States of America
| | - Brianna M Dufek
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska, United States of America
| | - Daniel T Meehan
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska, United States of America
| | - Marisa Zallocchi
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska, United States of America
| | - Michael Anne Gratton
- Department of Otolaryngology, Saint Louis University, Saint Louis, Missouri, United States of America
| | - Grady Phillips
- Department of Otolaryngology, Saint Louis University, Saint Louis, Missouri, United States of America
| | - Dominic Cosgrove
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska, United States of America; Department of Biochemistry, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
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Ning L, Kurihara H, de Vega S, Ichikawa-Tomikawa N, Xu Z, Nonaka R, Kazuno S, Yamada Y, Miner JH, Arikawa-Hirasawa E. Laminin α1 regulates age-related mesangial cell proliferation and mesangial matrix accumulation through the TGF-β pathway. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:1683-94. [PMID: 24720953 DOI: 10.1016/j.ajpath.2014.02.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 01/22/2014] [Accepted: 02/18/2014] [Indexed: 12/30/2022]
Abstract
Laminin α1 (LAMA1), a subunit of the laminin-111 basement membrane component, has been implicated in various biological functions in vivo and in vitro. Although LAMA1 is present in kidney, its roles in the kidney are unknown because of early embryonic lethality. Herein, we used a viable conditional knockout mouse model with a deletion of Lama1 in the epiblast lineage (Lama1(CKO)) to study the role of LAMA1 in kidney development and function. Adult Lama1(CKO) mice developed focal glomerulosclerosis and proteinuria with age. In addition, mesangial cell proliferation was increased, and the mesangial matrix, which normally contains laminin-111, was greatly expanded. In vitro, mesangial cells from Lama1(CKO) mice exhibited significantly increased proliferation compared with those from controls. This increased proliferation was inhibited by the addition of exogenous LAMA1-containing laminin-111, but not by laminin-211 or laminin-511, suggesting a specific role for LAMA1 in regulating mesangial cell behavior. Moreover, the absence of LAMA1 increased transforming growth factor (TGF)-β1-induced Smad2 phosphorylation, and inhibitors of TGF-β1 receptor I kinase blocked Smad2 phosphorylation in both control and Lama1(CKO) mesangial cells, indicating that the increased Smad2 phosphorylation occurred in the absence of LAMA1 via the TGF-β1 receptor. These findings suggest that LAMA1 plays a critical role in kidney function and kidney aging by regulating the mesangial cell population and mesangial matrix deposition through TGF-β/Smad signaling.
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Affiliation(s)
- Liang Ning
- Research Institute for Diseases of Old Age, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Hidetake Kurihara
- Department of Anatomy and Life Structure, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Susana de Vega
- Research Institute for Diseases of Old Age, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Naoki Ichikawa-Tomikawa
- Research Institute for Diseases of Old Age, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan; Department of Basic Pathology, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Zhuo Xu
- Research Institute for Diseases of Old Age, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Risa Nonaka
- Research Institute for Diseases of Old Age, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Saiko Kazuno
- Division of Proteomics and Biomolecular Science, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yoshihiko Yamada
- National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
| | - Jeffrey H Miner
- Renal Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Eri Arikawa-Hirasawa
- Research Institute for Diseases of Old Age, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan; Department of Neurology, BioMedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.
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Rubel D, Frese J, Martin M, Leibnitz A, Girgert R, Miosge N, Eckes B, Müller GA, Gross O. Collagen receptors integrin alpha2beta1 and discoidin domain receptor 1 regulate maturation of the glomerular basement membrane and loss of integrin alpha2beta1 delays kidney fibrosis in COL4A3 knockout mice. Matrix Biol 2014; 34:13-21. [PMID: 24480069 DOI: 10.1016/j.matbio.2014.01.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 01/15/2014] [Accepted: 01/16/2014] [Indexed: 02/06/2023]
Abstract
Maturation of the glomerular basement membrane (GBM) is essential for maintaining the integrity of the renal filtration barrier. Impaired maturation causes proteinuria and renal fibrosis in the type IV collagen disease Alport syndrome. This study evaluates the role of collagen receptors in maturation of the GBM, matrix accumulation and renal fibrosis by using mice deficient for discoidin domain receptor 1 (DDR1), integrin subunit α2 (ITGA2), and type IV collagen α3 (COL4A3). Loss of both collagen receptors DDR1 and integrin α2β1 delays maturation of the GBM: due to a porous GBM filtration barrier high molecular weight proteinuria that more than doubles between day 60 and day 100. Thereafter, maturation of the GBM causes proteinuria to drop down to one tenth until day 200. Proteinuria and the porous GBM cause accumulation of glomerular and tubulointerstitial matrix, which both decrease significantly after GBM-maturation until day 250. In parallel, in a disease with impaired GBM-maturation such as Alport syndrome, loss of integrin α2β1 positively delays renal fibrosis: COL4A3(-/-)/ITGA2(-/-) double knockouts exhibited reduced proteinuria and urea nitrogen compared to COL4A3(-/-)/ITGA2(+/-) and COL4A3(-/-)/ITGA2(+/+) mice. The double knockouts lived 20% longer and showed less glomerular and tubulointerstitial extracellular matrix deposition than the COL4A3(-/-) Alport mice with normal integrin α2β1 expression. Electron microscopy illustrated improvements in the glomerular basement membrane structure. MMP2, MMP9, MMP12 and TIMP1 were expressed at significantly higher levels (compared to wild-type mice) in COL4A3(-/-)/ITGA2(+/+) Alport mice, but not in COL4A3(+/+)/ITGA2(-/-) mice. In conclusion, the collagen receptors DDR1 and integrin α2β1 contribute to regulate GBM-maturation and to control matrix accumulation. As demonstrated in the type IV collagen disease Alport syndrome, glomerular cell-matrix interactions via collagen receptors play an important role in the progression of renal fibrosis.
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Affiliation(s)
- Diana Rubel
- Clinic of Nephrology and Rheumatology, University Medicine Goettingen, Goettingen, Germany
| | - Jenny Frese
- Clinic of Nephrology and Rheumatology, University Medicine Goettingen, Goettingen, Germany; Dept. of Prosthodontics, Tissue Regeneration Work Group, University Medicine Goettingen, Goettingen, Germany
| | - Maria Martin
- Clinic of Nephrology and Rheumatology, University Medicine Goettingen, Goettingen, Germany
| | - Alexander Leibnitz
- Clinic of Nephrology and Rheumatology, University Medicine Goettingen, Goettingen, Germany
| | - Rainer Girgert
- Clinic of Nephrology and Rheumatology, University Medicine Goettingen, Goettingen, Germany
| | - Nicolai Miosge
- Dept. of Prosthodontics, Tissue Regeneration Work Group, University Medicine Goettingen, Goettingen, Germany
| | - Beate Eckes
- Dept. of Dermatology, University of Cologne, Cologne, Germany
| | - Gerhard-Anton Müller
- Clinic of Nephrology and Rheumatology, University Medicine Goettingen, Goettingen, Germany
| | - Oliver Gross
- Clinic of Nephrology and Rheumatology, University Medicine Goettingen, Goettingen, Germany.
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Abstract
Integrin α1β1 is widely expressed in mesenchyme and the immune system, as well as a minority of epithelial tissues. Signaling through α1 contributes to the regulation of extracellular matrix composition, in addition to supplying in some tissues a proliferative and survival signal that appears to be unique among the collagen binding integrins. α1 provides a tissue retention function for cells of the immune system including monocytes and T cells, where it also contributes to their long-term survival, providing for peripheral T cell memory, and contributing to diseases of autoimmunity. The viability of α1 null mice, as well as the generation of therapeutic monoclonal antibodies against this molecule, have enabled studies of the role of α1 in a wide range of pathophysiological circumstances. The immune functions of α1 make it a rational therapeutic target.
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Lin X, Suh JH, Go G, Miner JH. Feasibility of repairing glomerular basement membrane defects in Alport syndrome. J Am Soc Nephrol 2013; 25:687-92. [PMID: 24262794 DOI: 10.1681/asn.2013070798] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Alport syndrome is a hereditary glomerular disease that leads to kidney failure. It is caused by mutations affecting one of three chains of the collagen α3α4α5(IV) heterotrimer, which forms the major collagen IV network of the glomerular basement membrane (GBM). In the absence of the α3α4α5(IV) network, the α1α1α2(IV) network substitutes, but it is insufficient to maintain normal kidney function. Inhibition of angiotensin-converting enzyme slows progression to kidney failure in patients with Alport syndrome but is not a cure. Restoration of the normal collagen α3α4α5(IV) network in the GBM, by either cell- or gene-based therapy, is an attractive and logical approach toward a cure, but whether or not the abnormal GBM can be repaired once it has formed and is functioning is unknown. Using a mouse model of Alport syndrome and an inducible transgene system, we found that secretion of α3α4α5(IV) heterotrimers by podocytes into a preformed, abnormal, filtering Alport GBM is effective at restoring the missing collagen IV network, slowing kidney disease progression, and extending life span. This proof-of-principle study demonstrates the plasticity of the mature GBM and validates the pursuit of therapeutic approaches aimed at normalizing the GBM to prolong kidney function.
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43
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Giani M, Mastrangelo A, Villa R, Turolo S, Marra G, Tirelli AS, Hopfer H, Edefonti A. Alport syndrome: the effects of spironolactone on proteinuria and urinary TGF-β1. Pediatr Nephrol 2013; 28:1837-42. [PMID: 23748277 DOI: 10.1007/s00467-013-2490-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Revised: 03/16/2013] [Accepted: 04/09/2013] [Indexed: 12/11/2022]
Abstract
BACKGROUND Alport syndrome (AS) is a progressive hereditary glomerular disease. Recent data indicate that aldosterone promotes fibrosis mediated by the transforming growth factor-β1 (TGF-β1) pathway, which may worsen proteinuria. Spironolactone (SP) antagonizes aldosterone and this study aimed to evaluate the efficacy of SP in reducing proteinuria and urinary TGF-β1 excretion in proteinuric AS patients. METHODS The study involved ten children with AS, normal renal function, and persistent proteinuria (>6 months; uPr/uCr ratio >1). SP 25 mg once a day for 6 months was added to existing ACE inhibitor treatment with or without angiotensin-II receptor blockade. Urine and blood samples were examined monthly. Urinary TGF-β1 levels were measured twice before and three times during SP treatment. Plasma renin activity (PRA) and serum aldosterone levels were also measured. In eight patients, uProt/uCreat was also assessed after 9 months and 12 months of SP treatment. RESULTS After beginning SP therapy, all patients showed significant decrease in mean uProt/uCreat ratio (1.77 ± 0.8 to 0.86 ± 0.6; p < 0.001) and mean urinary TGF-β1 levels (104 ± 54 to 41 ± 20 pg/mgCreatinine; p < 0.01), beginning after 30 days of treatment and remaining stable throughout SP administration. PRA remain unchanged, and mean serum aldosterone increased from 105 ± 72 pg/ml to 303 ± 156 pg/ml (p < 0.001). The only side effect was gynecomastia in an obese boy. After 1 year of therapy, mean uProt/uCreat remains low (0.82 ± 0.48). CONCLUSIONS Addition of SP to ACE-I treatment with or without angiotensin II receptor blokers (ARB) significantly reduced proteinuria. This was mediated by decreased urinary TGF-β1 levels and not associated with major side effects.
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Affiliation(s)
- Marisa Giani
- Pediatric Nephrology and Dialysis Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via della Commenda 9, 20122, Milan, Italy
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Zallocchi M, Johnson BM, Meehan DT, Delimont D, Cosgrove D. α1β1 integrin/Rac1-dependent mesangial invasion of glomerular capillaries in Alport syndrome. THE AMERICAN JOURNAL OF PATHOLOGY 2013; 183:1269-1280. [PMID: 23911822 DOI: 10.1016/j.ajpath.2013.06.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 06/11/2013] [Accepted: 06/14/2013] [Indexed: 01/27/2023]
Abstract
Alport syndrome, hereditary glomerulonephritis with hearing loss, results from mutations in type IV collagen COL4A3, COL4A4, or COL4A5 genes. The mechanism for delayed glomerular disease onset is unknown. Comparative analysis of Alport mice and CD151 knockout mice revealed progressive accumulation of laminin 211 in the glomerular basement membrane. We show mesangial processes invading the capillary loops of both models as well as in human Alport glomeruli, as the likely source of this laminin. L-NAME salt-induced hypertension accelerated mesangial cell process invasion. Cultured mesangial cells showed reduced migratory potential when treated with either integrin-linked kinase inhibitor or Rac1 inhibitor, or by deletion of integrin α1. Treatment of Alport mice with Rac1 inhibitor or deletion of integrin α1 reduced mesangial cell process invasion of the glomerular capillary tuft. Laminin α2-deficient Alport mice show reduced mesangial process invasion, and cultured laminin α2-null cells showed reduced migratory potential, indicating a functional role for mesangial laminins in progression of Alport glomerular pathogenesis. Collectively, these findings predict a role for biomechanical insult in the induction of integrin α1β1-dependent Rac1-mediated mesangial cell process invasion of the glomerular capillary tuft as an initiation mechanism of Alport glomerular pathology.
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Affiliation(s)
- Marisa Zallocchi
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska
| | - Brianna M Johnson
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska
| | - Daniel T Meehan
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska
| | - Duane Delimont
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska
| | - Dominic Cosgrove
- Department of Genetics, Boys Town National Research Hospital, Omaha, Nebraska; Department of Biochemistry, University of Nebraska Medical Center, Omaha, Nebraska.
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45
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An update on the pathomechanisms and future therapies of Alport syndrome. Pediatr Nephrol 2013; 28:1025-36. [PMID: 22903660 DOI: 10.1007/s00467-012-2272-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 07/12/2012] [Accepted: 07/13/2012] [Indexed: 01/08/2023]
Abstract
Alport Syndrome (AS) is an inherited progressive disease that is caused by mutations of the genes encoding the key collagen chains, α3, α4, and α5, which are necessary for the composition of collagen type IV to form a robust glomerular basement membrane (GBM), capable of withstanding the significant biomechanical strain to which the glomerulus is subjected. Progressive loss of the filtration barrier allows excessive proteinuria, which ultimately leads to end-stage kidney disease (ESKD). The evidence for a beneficial renoprotective effect of renin-angiotensin-aldosterone system (RAAS) blockade by angiotensin-converting enzyme (ACE) inhibition and/or angiotensin receptor blockers (ARBs) is well established in AS and recent evidence has shown that it can significantly delay the time to onset of renal replacement therapy and ESKD. Future potential treatments of AS disease progression are evaluated in this review.
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Abstract
A major hallmark of chronic kidney injury is fibrosis, which is characterized by increased accumulation of extracellular matrix components that replace the damaged tissue. Normally, the synthesis and degradation of extracellular matrix components are finely regulated; however, when matrix replacement goes unchecked, there is unwanted and irreversible tissue scarring with consequent organ damage, organ failure, and, in certain cases, death. Many factors, including cell-matrix interactions, play a role in the development of renal fibrosis. Cell-matrix interactions are made possible by integrins, a family of transmembrane receptors that, upon binding to the extracellular matrix, activate intracellular signaling. Thus, they control various cell functions, including survival, proliferation, migration, and matrix homeostasis. Genetic mutations in humans and the development of animal models lacking integrins in selective parts of the kidney have improved our understanding of molecular mechanisms and pathways controlling matrix remodeling in kidney disease. Here we outline the major integrins involved in kidney disease and some of the major molecular mechanisms whereby integrins contribute to kidney fibrosis.
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Affiliation(s)
- Ambra Pozzi
- Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN 27232, USA.
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47
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Steenhard BM, Vanacore R, Friedman D, Zelenchuk A, Stroganova L, Isom K, St. John PL, Hudson BG, Abrahamson DR. Upregulated expression of integrin α1 in mesangial cells and integrin α3 and vimentin in podocytes of Col4a3-null (Alport) mice. PLoS One 2012; 7:e50745. [PMID: 23236390 PMCID: PMC3517557 DOI: 10.1371/journal.pone.0050745] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 10/22/2012] [Indexed: 01/19/2023] Open
Abstract
Alport disease in humans, which usually results in proteinuria and kidney failure, is caused by mutations to the COL4A3, COL4A4, or COL4A5 genes, and absence of collagen α3α4α5(IV) networks found in mature kidney glomerular basement membrane (GBM). The Alport mouse harbors a deletion of the Col4a3 gene, which also results in the lack of GBM collagen α3α4α5(IV). This animal model shares many features with human Alport patients, including the retention of collagen α1α2α1(IV) in GBMs, effacement of podocyte foot processes, gradual loss of glomerular barrier properties, and progression to renal failure. To learn more about the pathogenesis of Alport disease, we undertook a discovery proteomics approach to identify proteins that were differentially expressed in glomeruli purified from Alport and wild-type mouse kidneys. Pairs of cy3- and cy5-labeled extracts from 5-week old Alport and wild-type glomeruli, respectively, underwent 2-dimensional difference gel electrophoresis. Differentially expressed proteins were digested with trypsin and prepared for mass spectrometry, peptide ion mapping/fingerprinting, and protein identification through database searching. The intermediate filament protein, vimentin, was upregulated ∼2.5 fold in Alport glomeruli compared to wild-type. Upregulation was confirmed by quantitative real time RT-PCR of isolated Alport glomeruli (5.4 fold over wild-type), and quantitative confocal immunofluorescence microscopy localized over-expressed vimentin specifically to Alport podocytes. We next hypothesized that increases in vimentin abundance might affect the basement membrane protein receptors, integrins, and screened Alport and wild-type glomeruli for expression of integrins likely to be the main receptors for GBM type IV collagen and laminin. Quantitative immunofluorescence showed an increase in integrin α1 expression in Alport mesangial cells and an increase in integrin α3 in Alport podocytes. We conclude that overexpression of mesangial integrin α1 and podocyte vimentin and integrin α3 may be important features of glomerular Alport disease, possibly affecting cell-signaling, cell shape and cellular adhesion to the GBM.
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Affiliation(s)
- Brooke M. Steenhard
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - Roberto Vanacore
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - David Friedman
- Department of Biochemistry, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Adrian Zelenchuk
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - Larysa Stroganova
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - Kathryn Isom
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - Patricia L. St. John
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - Billy G. Hudson
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Dale R. Abrahamson
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- * E-mail:
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48
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Chen YM, Miner JH. Glomerular basement membrane and related glomerular disease. Transl Res 2012; 160:291-7. [PMID: 22683419 PMCID: PMC3477400 DOI: 10.1016/j.trsl.2012.03.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2011] [Revised: 02/20/2012] [Accepted: 03/15/2012] [Indexed: 01/11/2023]
Abstract
The glomerular basement membrane (GBM) is lined by fenestrated endothelium from the capillary-lumen side and by interdigitating foot processes of the podocytes from the urinary- space side. These three layers of the glomerular capillary wall constitute the functional unit of the glomerular filtration barrier. The GBM is assembled through an interweaving of type IV collagen with laminins, nidogen, and sulfated proteoglycans. Mutations in genes encoding LAMB2, COL4A3, COL4A4, and COL4A5 cause glomerular disease in humans as well as in mice. In addition, laminin α5 mutation in podocytes leads to proteinuria and renal failure in mice. Moreover, more neoepitopes in Goodpasture's disease and for the first time alloepitopes in Alport post-transplantation nephritis have been located in the collagen α5(IV) NC1 domain. These discoveries underscore the importance of the GBM in establishing and maintaining the integrity of the glomerular filtration barrier.
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Affiliation(s)
- Ying Maggie Chen
- Renal Division, Washington University School of Medicine, St. Louis, MO, USA.
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Weinreb PH, Li S, Gao SX, Liu T, Pepinsky RB, Caravella JA, Lee JH, Woods VL. Dynamic structural changes are observed upon collagen and metal ion binding to the integrin α1 I domain. J Biol Chem 2012; 287:32897-912. [PMID: 22847004 PMCID: PMC3463359 DOI: 10.1074/jbc.m112.354365] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 07/11/2012] [Indexed: 02/05/2023] Open
Abstract
We have applied hydrogen-deuterium exchange mass spectrometry, in conjunction with differential scanning calorimetry and protein stability analysis, to examine solution dynamics of the integrin α1 I domain induced by the binding of divalent cations, full-length type IV collagen, or a function-blocking monoclonal antibody. These studies revealed features of integrin activation and α1I-ligand complexes that were not detected by static crystallographic data. Mg(2+) and Mn(2+) stabilized α1I but differed in their effects on exchange rates in the αC helix. Ca(2+) impacted α1I conformational dynamics without altering its gross thermal stability. Interaction with collagen affected the exchange rates in just one of three metal ion-dependent adhesion site (MIDAS) loops, suggesting that MIDAS loop 2 plays a primary role in mediating ligand binding. Collagen also induced changes consistent with increased unfolding in both the αC and allosteric C-terminal helices of α1I. The antibody AQC2, which binds to α1I in a ligand-mimetic manner, also reduced exchange in MIDAS loop 2 and increased exchange in αC, but it did not impact the C-terminal region. This is the first study to directly demonstrate the conformational changes induced upon binding of an integrin I domain to a full-length collagen ligand, and it demonstrates the utility of the deuterium exchange mass spectrometry method to study the solution dynamics of integrin/ligand and integrin/metal ion interactions. Based on the ligand and metal ion binding data, we propose a model for collagen-binding integrin activation that explains the differing abilities of Mg(2+), Mn(2+), and Ca(2+) to activate I domain-containing integrins.
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Affiliation(s)
| | - Sheng Li
- the Department of Medicine and Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California 92093-0656
| | - Sharon X. Gao
- From Biogen Idec, Inc., Cambridge, Massachusetts 02142 and
| | - Tong Liu
- the Department of Medicine and Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California 92093-0656
| | | | | | - Jun H. Lee
- the Department of Medicine and Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California 92093-0656
| | - Virgil L. Woods
- the Department of Medicine and Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California 92093-0656
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50
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Glomerular pathology in Alport syndrome: a molecular perspective. Pediatr Nephrol 2012; 27:885-90. [PMID: 21455721 PMCID: PMC3484979 DOI: 10.1007/s00467-011-1868-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 03/09/2011] [Accepted: 03/10/2011] [Indexed: 01/28/2023]
Abstract
We have known for some time that mutations in the genes encoding 3 of the 6 type IV collagen chains are the underlying defect responsible for both X-linked (where the COL4A5 gene is involved) and autosomal (where either COL4A3 or COL4A4 genes are involved) Alport syndrome. The result of these mutations is the absence of the sub-epithelial network of all three chains in the glomerular basement membrane (GBM), resulting, at maturity, in a type IV collagen GBM network comprising only α1(IV) and α2(IV) chains. The altered GBM functions adequately in early life. Eventually, there is onset of proteinuria associated with the classic and progressive irregular thickening, thinning, and splitting of the GBM, which culminates in end-stage renal failure. We have learned much about the molecular events associated with disease onset and progression through the study of animal models for Alport syndrome, and have identified some potential therapeutic approaches that may serve to delay the onset or slow the progression of the disease. This review focuses on where we are in our understanding of the disease, where we need to go to understand the molecular triggers that set the process in motion, and what emergent therapeutic approaches show promise for ameliorating disease progression in the clinic.
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