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Wang L, Liang C, Zheng N, Yang C, Yan S, Wang X, Zuo Z, He C. Kidney injury contributes to edema of zebrafish larvae caused by quantum dots. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168420. [PMID: 37963533 DOI: 10.1016/j.scitotenv.2023.168420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 10/29/2023] [Accepted: 11/06/2023] [Indexed: 11/16/2023]
Abstract
Edema represents a notable outcome in fishes exposed to aquatic pollutants, yet the underlying etiology remains inadequately understood. This investigation delves into the etiological factors of edema formation in 7 days post fertilization (dpf) zebrafish larvae following their exposure to InP/ZnS quantum dots (QDs), which was chosen as a prototypical edema inducer. Given the fundamental role of the kidney in osmoregulation, we used transgenic zebrafish lines featuring fluorescent protein labeling of the glomerulus, renal tubule, and blood vessels, in conjunction with histopathological scrutiny. We identified the pronounced morphological and structural aberrations within the pronephros. By means of tissue mass spectrometry imaging and hyperspectral microscopy, we discerned the accumulation of InP/ZnS QDs in the pronephros. Moreover, InP/ZnS QDs impeded the renal clearance capacity of the pronephros, as substantiated by diminished uptake of FITC-dextran. InP/ZnS QDs also disturbed the expression levels of marker genes associated with kidney development and osmoregulatory function at the earlier time points, which preceded the onset of edema. These results suggest that impaired fluid clearance most likely resulting from pronephros injury contributes to the emergence of zebrafish edema. Briefly, our study provides a perspective: the kidney developmental injury induced by exogenous substances may regulate edema in a zebrafish model.
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Affiliation(s)
- Luanjin Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Nephrology, Fujian Clinical Research Center for Chronic Glomerular Disease, The Fifth Hospital of Xiamen, Xiang'an Branch of the First Affiliated Hospital, Xiamen University, Xiamen, Fujian 361102, China
| | - Cixin Liang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Nephrology, Fujian Clinical Research Center for Chronic Glomerular Disease, The Fifth Hospital of Xiamen, Xiang'an Branch of the First Affiliated Hospital, Xiamen University, Xiamen, Fujian 361102, China
| | - Naying Zheng
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Nephrology, Fujian Clinical Research Center for Chronic Glomerular Disease, The Fifth Hospital of Xiamen, Xiang'an Branch of the First Affiliated Hospital, Xiamen University, Xiamen, Fujian 361102, China
| | - Chunyan Yang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Nephrology, Fujian Clinical Research Center for Chronic Glomerular Disease, The Fifth Hospital of Xiamen, Xiang'an Branch of the First Affiliated Hospital, Xiamen University, Xiamen, Fujian 361102, China
| | - Sen Yan
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (i-ChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xiang Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (i-ChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Zhenghong Zuo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Nephrology, Fujian Clinical Research Center for Chronic Glomerular Disease, The Fifth Hospital of Xiamen, Xiang'an Branch of the First Affiliated Hospital, Xiamen University, Xiamen, Fujian 361102, China; Department of Endocrinology, Xiang'an Hospital of Xiamen University, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, China
| | - Chengyong He
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Nephrology, Fujian Clinical Research Center for Chronic Glomerular Disease, The Fifth Hospital of Xiamen, Xiang'an Branch of the First Affiliated Hospital, Xiamen University, Xiamen, Fujian 361102, China; Department of Endocrinology, Xiang'an Hospital of Xiamen University, School of Medicine, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, China.
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Drummond BE, Ercanbrack WS, Wingert RA. Modeling Podocyte Ontogeny and Podocytopathies with the Zebrafish. J Dev Biol 2023; 11:jdb11010009. [PMID: 36810461 PMCID: PMC9944608 DOI: 10.3390/jdb11010009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/11/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Podocytes are exquisitely fashioned kidney cells that serve an essential role in the process of blood filtration. Congenital malformation or damage to podocytes has dire consequences and initiates a cascade of pathological changes leading to renal disease states known as podocytopathies. In addition, animal models have been integral to discovering the molecular pathways that direct the development of podocytes. In this review, we explore how researchers have used the zebrafish to illuminate new insights about the processes of podocyte ontogeny, model podocytopathies, and create opportunities to discover future therapies.
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3
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Mozaffari K, Mekonnen M, Harary M, Lum M, Aguirre B, Chandla A, Wadehra M, Yang I. Epithelial membrane protein 2 (EMP2): A systematic review of its implications in pathogenesis. Acta Histochem 2023; 125:151976. [PMID: 36455339 DOI: 10.1016/j.acthis.2022.151976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 11/16/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Epithelial membrane protein 2 (EMP2) is a cell surface protein composed of approximately 160 amino acids and encoded by the growth arrest-specific 3 (GAS3)/peripheral myelin protein 22 kDa (PMP22) gene family. Although EMP2 expression has been investigated in several diseases, much remains unknown regarding its mechanism of action and the extent of its role in pathogenesis. Our aim was to perform a systematic review on the involvement of EMP2 in disease processes and the current usage of anti-EMP2 therapies. METHODS A Boolean search of the English-language medical literature was performed. PubMed, Scopus, Cochrane, and Web of Science were used to identify relevant citations. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS 52 studies met the inclusion criteria for qualitative analysis. Of those, 28 (53.8%) were human-only studies, 11 (21.2%) were animal-only studies, and 13 (25%) studies included both human and animal models. Furthermore, 34 (65.4%) studies focused on EMP2's role in neoplasms, while the remaining 18 (34.6%) articles evaluated its role in other pathologies. CONCLUSION Overall, the evidence suggests the mechanisms of action of EMP2 are context dependent. Promising results have been produced by utilizing EMP2 as a biomarker and therapeutic target. More studies are warranted to better understand the mechanism and comprehend the role of EMP2 in the pathogenesis of diseases.
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Affiliation(s)
- Khashayar Mozaffari
- Department of Neurosurgery, University of California, Los Angeles (UCLA), Los Angeles, CA, United States
| | - Mahlet Mekonnen
- Department of Neurosurgery, University of California, Los Angeles (UCLA), Los Angeles, CA, United States
| | - Maya Harary
- Department of Neurosurgery, University of California, Los Angeles (UCLA), Los Angeles, CA, United States
| | - Meachelle Lum
- Department of Neurosurgery, University of California, Los Angeles (UCLA), Los Angeles, CA, United States
| | - Brian Aguirre
- Department of Pathology and Laboratory Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA, United States
| | - Anubhav Chandla
- Department of Neurosurgery, University of California, Los Angeles (UCLA), Los Angeles, CA, United States
| | - Madhuri Wadehra
- Department of Pathology and Laboratory Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA, United States
| | - Isaac Yang
- Department of Neurosurgery, University of California, Los Angeles (UCLA), Los Angeles, CA, United States.
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4
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Bondue T, Arcolino FO, Veys KRP, Adebayo OC, Levtchenko E, van den Heuvel LP, Elmonem MA. Urine-Derived Epithelial Cells as Models for Genetic Kidney Diseases. Cells 2021; 10:cells10061413. [PMID: 34204173 PMCID: PMC8230018 DOI: 10.3390/cells10061413] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 05/28/2021] [Accepted: 06/02/2021] [Indexed: 12/11/2022] Open
Abstract
Epithelial cells exfoliated in human urine can include cells anywhere from the urinary tract and kidneys; however, podocytes and proximal tubular epithelial cells (PTECs) are by far the most relevant cell types for the study of genetic kidney diseases. When maintained in vitro, they have been proven extremely valuable for discovering disease mechanisms and for the development of new therapies. Furthermore, cultured patient cells can individually represent their human sources and their specific variants for personalized medicine studies, which are recently gaining much interest. In this review, we summarize the methodology for establishing human podocyte and PTEC cell lines from urine and highlight their importance as kidney disease cell models. We explore the well-established and recent techniques of cell isolation, quantification, immortalization and characterization, and we describe their current and future applications.
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Affiliation(s)
- Tjessa Bondue
- Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium; (T.B.); (F.O.A.); (K.R.P.V.); (O.C.A.); (E.L.); (L.P.v.d.H.)
| | - Fanny O. Arcolino
- Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium; (T.B.); (F.O.A.); (K.R.P.V.); (O.C.A.); (E.L.); (L.P.v.d.H.)
| | - Koenraad R. P. Veys
- Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium; (T.B.); (F.O.A.); (K.R.P.V.); (O.C.A.); (E.L.); (L.P.v.d.H.)
- Department of Pediatrics, Division of Pediatric Nephrology, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Oyindamola C. Adebayo
- Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium; (T.B.); (F.O.A.); (K.R.P.V.); (O.C.A.); (E.L.); (L.P.v.d.H.)
- Centre for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Elena Levtchenko
- Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium; (T.B.); (F.O.A.); (K.R.P.V.); (O.C.A.); (E.L.); (L.P.v.d.H.)
- Department of Pediatrics, Division of Pediatric Nephrology, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Lambertus P. van den Heuvel
- Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium; (T.B.); (F.O.A.); (K.R.P.V.); (O.C.A.); (E.L.); (L.P.v.d.H.)
- Department of Pediatric Nephrology, Radboud University Medical Center, 6500 Nijmegen, The Netherlands
| | - Mohamed A. Elmonem
- Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo 11628, Egypt
- Correspondence:
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van den Broek M, Smeets B, Schreuder MF, Jansen J. The podocyte as a direct target of glucocorticoids in nephrotic syndrome. Nephrol Dial Transplant 2021; 37:1808-1815. [PMID: 33515261 DOI: 10.1093/ndt/gfab016] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Indexed: 12/14/2022] Open
Abstract
Nephrotic syndrome (NS) is characterized by massive proteinuria; podocyte loss or altered function is a central event in its pathophysiology. Treatment with glucocorticoids is the mainstay of therapy. However, many patients experience one or multiple relapses and prolonged use may be associated with severe adverse effects. Recently, the beneficial effects of glucocorticoids have been attributed to a direct effect on podocytes in addition to the well-known immunosuppressive effects. The molecular effects of glucocorticoid action have been studied using animal and cell models of NS. This review provides a comprehensive overview of different molecular mediators regulated by glucocorticoids including an overview of the model systems that were used to study them. Glucocorticoids are described to stimulate podocyte recovery by restoring pro-survival signaling of slit diaphragm related proteins and limiting inflammatory responses. Of special interest is the effect of glucocorticoids on stabilizing the cytoskeleton of podocytes, since these effects are also described for other therapeutic agents used in NS, such as cyclosporin. Current models provide much insight, but do not fully recapitulate the human condition since the pathophysiology underlying NS is poorly understood. New and promising models include the glomerulus-on-a-chip and kidney organoids, which have the potential to be further developed into functional NS models in the future.
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Affiliation(s)
- Martijn van den Broek
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands.,Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Amalia Children's Hospital, Nijmegen, The Netherlands
| | - Bart Smeets
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Michiel F Schreuder
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Amalia Children's Hospital, Nijmegen, The Netherlands
| | - Jitske Jansen
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands.,Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Amalia Children's Hospital, Nijmegen, The Netherlands
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6
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Lin WC, Gowdy KM, Madenspacher JH, Zemans RL, Yamamoto K, Lyons-Cohen M, Nakano H, Janardhan K, Williams CJ, Cook DN, Mizgerd JP, Fessler MB. Epithelial membrane protein 2 governs transepithelial migration of neutrophils into the airspace. J Clin Invest 2020; 130:157-170. [PMID: 31550239 DOI: 10.1172/jci127144] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 09/18/2019] [Indexed: 02/06/2023] Open
Abstract
Whether respiratory epithelial cells regulate the final transit of extravasated neutrophils into the inflamed airspace or are a passive barrier is poorly understood. Alveolar epithelial type 1 (AT1) cells, best known for solute transport and gas exchange, have few established immune roles. Epithelial membrane protein 2 (EMP2), a tetraspan protein that promotes recruitment of integrins to lipid rafts, is highly expressed in AT1 cells but has no known function in lung biology. Here, we show that Emp2-/- mice exhibit reduced neutrophil influx into the airspace after a wide range of inhaled exposures. During bacterial pneumonia, Emp2-/- mice had attenuated neutrophilic lung injury and improved survival. Bone marrow chimeras, intravital neutrophil labeling, and in vitro assays suggested that defective transepithelial migration of neutrophils into the alveolar lumen occurs in Emp2-/- lungs. Emp2-/- AT1 cells had dysregulated surface display of multiple adhesion molecules, associated with reduced raft abundance. Epithelial raft abundance was dependent upon putative cholesterol-binding motifs in EMP2, whereas EMP2 supported adhesion molecule display and neutrophil transmigration through suppression of caveolins. Taken together, we propose that EMP2-dependent membrane organization ensures proper display on AT1 cells of a suite of proteins required to instruct paracellular neutrophil traffic into the alveolus.
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Affiliation(s)
- Wan-Chi Lin
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Kymberly M Gowdy
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Jennifer H Madenspacher
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Rachel L Zemans
- Department of Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Kazuko Yamamoto
- Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts, USA.,Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan.,Department of Clinical Research Center, National Hospital Organization Nagasaki Medical Center, Omura, Japan
| | - Miranda Lyons-Cohen
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Hideki Nakano
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Kyathanahalli Janardhan
- Cellular & Molecular Pathology Branch, National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA.,Integrated Laboratory Systems Inc., Research Triangle Park, North Carolina, USA
| | - Carmen J Williams
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Donald N Cook
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Joseph P Mizgerd
- Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Michael B Fessler
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
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7
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Blaine J, Dylewski J. Regulation of the Actin Cytoskeleton in Podocytes. Cells 2020; 9:cells9071700. [PMID: 32708597 PMCID: PMC7408282 DOI: 10.3390/cells9071700] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 06/30/2020] [Accepted: 07/07/2020] [Indexed: 12/13/2022] Open
Abstract
Podocytes are an integral part of the glomerular filtration barrier, a structure that prevents filtration of large proteins and macromolecules into the urine. Podocyte function is dependent on actin cytoskeleton regulation within the foot processes, structures that link podocytes to the glomerular basement membrane. Actin cytoskeleton dynamics in podocyte foot processes are complex and regulated by multiple proteins and other factors. There are two key signal integration and structural hubs within foot processes that regulate the actin cytoskeleton: the slit diaphragm and focal adhesions. Both modulate actin filament extension as well as foot process mobility. No matter what the initial cause, the final common pathway of podocyte damage is dysregulation of the actin cytoskeleton leading to foot process retraction and proteinuria. Disruption of the actin cytoskeleton can be due to acquired causes or to genetic mutations in key actin regulatory and signaling proteins. Here, we describe the major structural and signaling components that regulate the actin cytoskeleton in podocytes as well as acquired and genetic causes of actin dysregulation.
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Affiliation(s)
- Judith Blaine
- Renal Division, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - James Dylewski
- Renal Division, University of Colorado Anschutz Medical Campus and Denver Health Medical Center, Aurora, CO 80045, USA
- Correspondence: ; Tel.: +303-724-4841
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8
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Hosseiniyan Khatibi SM, Ardalan M, Abediazar S, Zununi Vahed S. The impact of steroids on the injured podocytes in nephrotic syndrome. J Steroid Biochem Mol Biol 2020; 196:105490. [PMID: 31586640 DOI: 10.1016/j.jsbmb.2019.105490] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 09/03/2019] [Accepted: 09/30/2019] [Indexed: 12/17/2022]
Abstract
Nephrotic syndrome (NS), a common chronic kidney disease, embraces a variety of kidney disorders. Though Glucocorticoids (GCs) are generally used in the treatment of NS, their mechanism of action is poorly understood. A plethora of evidence indicates that podocytes are considered as the main target cells for the therapeutic strategies to prevent NS. GCs regulate the transactivation and transrepression of genes in podocytes that affect their morphological and cytoskeletal features, motility, apoptosis and survival rate. Moreover, they prevent protein leakage through the glomerular barrier membrane by affecting the synthesis, trafficking and posttranslational modifications of slit diaphragms components, podocytes' intercellular junctions. The response to the treatment is variable among different ethnics and populations and resistance to the steroids is detected in almost 50% of adult patients. Not only do pharmacokinetics and pharmacogenetics of steroids play a role in GC resistance but also the genetic variations in one or more podocyte related genes are connected with the steroid resistance in cases with NS. The focus of this review is to explain the underlying cellular and molecular mechanisms of GCs in podocytes. Understanding the mechanisms by which the GCs and GCs receptors in podocytes regulate the gene expression network and crosstalk with other molecular pathways would guarantee an optimum therapeutic benefit of steroid treatment.
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Affiliation(s)
| | | | - Sima Abediazar
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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9
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Mitrofanova A, Sosa MA, Fornoni A. Lipid mediators of insulin signaling in diabetic kidney disease. Am J Physiol Renal Physiol 2019; 317:F1241-F1252. [PMID: 31545927 PMCID: PMC6879940 DOI: 10.1152/ajprenal.00379.2019] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 09/19/2019] [Accepted: 09/19/2019] [Indexed: 12/30/2022] Open
Abstract
Diabetic kidney disease (DKD) affects ∼40% of patients with diabetes and is associated with high mortality rates. Among different cellular targets in DKD, podocytes, highly specialized epithelial cells of the glomerular filtration barrier, are injured in the early stages of DKD. Both clinical and experimental data support the role of preserved insulin signaling as a major contributor to podocyte function and survival. However, little is known about the key modulators of podocyte insulin signaling. This review summarizes the novel knowledge that intracellular lipids such as cholesterol and sphingolipids are major determinants of podocyte insulin signaling. In particular, the implications of these lipids on DKD development, progression, and treatment will be addressed.
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Affiliation(s)
- Alla Mitrofanova
- Katz Family Division of Nephrology and Hypertension, Department of Medicine, Miller School of Medicine, University of Miami, Miami, Florida
- Peggy and Harold Katz Family Drug Discovery Center, Miller School of Medicine, University of Miami, Miami, Florida
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida
| | - Marie Anne Sosa
- Katz Family Division of Nephrology and Hypertension, Department of Medicine, Miller School of Medicine, University of Miami, Miami, Florida
| | - Alessia Fornoni
- Katz Family Division of Nephrology and Hypertension, Department of Medicine, Miller School of Medicine, University of Miami, Miami, Florida
- Peggy and Harold Katz Family Drug Discovery Center, Miller School of Medicine, University of Miami, Miami, Florida
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10
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Donnan MD, Scott RP, Onay T, Tarjus A, Onay UV, Quaggin SE. Genetic Deletion of Emp2 Does Not Cause Proteinuric Kidney Disease in Mice. Front Med (Lausanne) 2019; 6:189. [PMID: 31508419 PMCID: PMC6718710 DOI: 10.3389/fmed.2019.00189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 08/09/2019] [Indexed: 12/15/2022] Open
Abstract
Nephrotic syndrome is one of the most common glomerular diseases in children and can be classified on the basis of steroid responsiveness. While multiple genetic causes have been discovered for steroid resistant nephrotic syndrome, the genetics of steroid sensitive nephrotic syndrome remains elusive. Mutations in Epithelial Membrane Protein 2 (EMP2), a member of the GAS3/PMP22 tetraspan family of proteins, were recently implicated as putative monogenic cause of steroid sensitive nephrotic syndrome. We investigated this hypothesis by developing Emp2 reporter and knockout mouse models. In lacZ reporter mice (engineered to drive expression of the enzyme β-galactosidase under the control of the endogenous murine Emp2 promoter), Emp2 promoter activity was not observed in podocytes but was particularly prominent in medium- and large-caliber arterial vessels in the kidney and other tissues where it localizes specifically in vascular smooth muscle cells (vSMCs) but not in the endothelium. Strong Emp2 expression was also found in non-vascular smooth muscle cells found in other organs like the stomach, bladder, and uterus. Global and podocyte-specific Emp2 knockout mice were viable and did not develop nephrotic syndrome showing no evidence of abnormal glomerular histology or ultrastructure. Altogether, our results do not support that loss of function of EMP2 represent a monogenic cause of proteinuric kidney disease. However, the expression pattern of Emp2 indicates that it may be relevant in smooth muscle function in various organs and tissues including the vasculature.
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Affiliation(s)
- Michael D Donnan
- Division of Nephrology and Hypertension, Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Rizaldy P Scott
- Division of Nephrology and Hypertension, Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Tuncer Onay
- Division of Nephrology and Hypertension, Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Antoine Tarjus
- Division of Nephrology and Hypertension, Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Ummiye Venus Onay
- Division of Nephrology and Hypertension, Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Susan E Quaggin
- Division of Nephrology and Hypertension, Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
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11
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Zhai X, Wang L, Xu C, Hou Q, Zhang L, Li Z, Qin W, Liu Z, Chen Z. Triptolide preserves glomerular barrier function via the inhibition of p53-mediated increase of GADD45B. Arch Biochem Biophys 2019; 671:210-217. [DOI: 10.1016/j.abb.2019.07.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 07/03/2019] [Accepted: 07/14/2019] [Indexed: 01/21/2023]
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12
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Jobst-Schwan T, Hoogstraten CA, Kolvenbach CM, Schmidt JM, Kolb A, Eddy K, Schneider R, Ashraf S, Widmeier E, Majmundar AJ, Hildebrandt F. Corticosteroid treatment exacerbates nephrotic syndrome in a zebrafish model of magi2a knockout. Kidney Int 2019; 95:1079-1090. [PMID: 31010479 DOI: 10.1016/j.kint.2018.12.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/21/2018] [Accepted: 12/13/2018] [Indexed: 01/31/2023]
Abstract
Recently, recessive mutations of MAGI2 were identified as a cause of steroid-resistant nephrotic syndrome (SRNS) in humans and mice. To further delineate the pathogenesis of MAGI2 loss of function, we generated stable knockout lines for the two zebrafish orthologues magi2a and magi2b by CRISPR/Cas9. We also developed a novel assay for the direct detection of proteinuria in zebrafish independent of transgenic background. Whereas knockout of magi2b did not yield a nephrotic syndrome phenotype, magi2a-/- larvae developed ascites, periorbital edema, and proteinuria, as indicated by increased excretion of low molecular weight protein. Electron microscopy demonstrated extensive podocyte foot process effacement. As in human SRNS, we observed genotype/phenotype correlation, with edema onset occurring earlier in zebrafish with truncating alleles (5-6 days post fertilization) versus hypomorphic alleles (19-20 days post fertilization). Paradoxically, corticosteroid treatment exacerbated the phenotype, with earlier onset of edema. In contrast, treatment with cyclosporine A or tacrolimus had no significant effect. Although RhoA signaling has been implicated as a downstream mediator of MAGI2 activity, targeting of the RhoA pathway did not modify the nephrotic syndrome phenotype. In the first CRISPR/Cas9 zebrafish knockout model of SRNS, we found that corticosteroids may have a paradoxical effect in the setting of specific genetic mutations.
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Affiliation(s)
- Tilman Jobst-Schwan
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Charlotte A Hoogstraten
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Caroline M Kolvenbach
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Johanna Magdalena Schmidt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Amy Kolb
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Kaitlyn Eddy
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ronen Schneider
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Shazia Ashraf
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Eugen Widmeier
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Amar J Majmundar
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Friedhelm Hildebrandt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
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13
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Torella D, Iaconetti C, Tarallo R, Marino F, Giurato G, Veneziano C, Aquila I, Scalise M, Mancuso T, Cianflone E, Valeriano C, Marotta P, Tammè L, Vicinanza C, Sasso FC, Cozzolino D, Torella M, Weisz A, Indolfi C. miRNA Regulation of the Hyperproliferative Phenotype of Vascular Smooth Muscle Cells in Diabetes. Diabetes 2018; 67:2554-2568. [PMID: 30257973 DOI: 10.2337/db17-1434] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Accepted: 09/14/2018] [Indexed: 02/05/2023]
Abstract
Harnessing the mechanisms underlying the exacerbated vascular remodeling in diabetes mellitus (DM) is pivotal to prevent the high toll of vascular diseases in patients with DM. miRNA regulates vascular smooth muscle cell (VSMC) phenotypic switch. However, miRNA modulation of the detrimental diabetic VSMC phenotype is underexplored. Streptozotocin-induced type 1 DM (T1DM) Wistar rats and type 2 DM (T2DM) Zucker rats underwent right carotid artery experimental angioplasty, and global miRNA/mRNA expression profiling was obtained by RNA sequencing (RNA-Seq). Two days after injury, a set of six miRNAs were found to be uniquely downregulated or upregulated in VSMCs both in T1DM and T2DM. Among these miRNAs, miR-29c and miR-204 were the most significantly misregulated in atherosclerotic plaques from patients with DM. miR-29c overexpression and miR-204 inhibition per se attenuated VSMC phenotypic switch in DM. Concomitant miR-29c overexpression and miR-204 inhibition fostered an additive reduction in VSMC proliferation. Epithelial membrane protein 2 (Emp2) and Caveolin-1 (Cav1) mRNAs were identified as direct targets of miR-29c and miR-204, respectively. Importantly, contemporary miR-29c overexpression and miR-204 inhibition in the injured artery robustly reduced arterial stenosis in DM rats. Thus, contemporaneous miR-29c activation and miR-204 inhibition in DM arterial tissues is necessary and sufficient to prevent the exaggerated VSMC growth upon injury.
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MESH Headings
- Animals
- Cell Proliferation/physiology
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 1/pathology
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/pathology
- Humans
- Male
- MicroRNAs/metabolism
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Plaque, Atherosclerotic/metabolism
- Plaque, Atherosclerotic/pathology
- Rats
- Rats, Wistar
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Affiliation(s)
- Daniele Torella
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Claudio Iaconetti
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Roberta Tarallo
- Laboratory of Molecular Medicine and Genomics, Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana," University of Salerno, Baronissi, Salerno, Italy
| | - Fabiola Marino
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Giorgio Giurato
- Laboratory of Molecular Medicine and Genomics, Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana," University of Salerno, Baronissi, Salerno, Italy
- Genomix4Life srl, Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana," University of Salerno, Baronissi, Salerno, Italy
| | - Claudia Veneziano
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Iolanda Aquila
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Mariangela Scalise
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Teresa Mancuso
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Eleonora Cianflone
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Chiara Valeriano
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Pina Marotta
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Laura Tammè
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Carla Vicinanza
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Ferdinando C Sasso
- Department of Internal and Experimental Medicine "Magrassi-Lanzara," University of Campania "L. Vanvitelli," Naples, Italy
| | - Domenico Cozzolino
- Department of Internal and Experimental Medicine "Magrassi-Lanzara," University of Campania "L. Vanvitelli," Naples, Italy
| | - Michele Torella
- Department of Cardiothoracic Sciences, University of Campania "L. Vanvitelli," Naples, Italy
| | - Alessandro Weisz
- Laboratory of Molecular Medicine and Genomics, Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana," University of Salerno, Baronissi, Salerno, Italy
| | - Ciro Indolfi
- Cardiovascular Institute, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
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14
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Wang L, Zhang L, Hou Q, Zhu X, Chen Z, Liu Z. Triptolide attenuates proteinuria and podocyte apoptosis via inhibition of NF-κB/GADD45B. Sci Rep 2018; 8:10843. [PMID: 30022148 PMCID: PMC6052061 DOI: 10.1038/s41598-018-29203-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 07/06/2018] [Indexed: 12/14/2022] Open
Abstract
Podocyte injury is a primary contributor to proteinuria. Triptolide is a major active component of Tripterygium wilfordii Hook F that exhibits potent antiproteinuric effects. We used our previously developed in vivo zebrafish model of inducible podocyte-target injury and found that triptolide treatment effectively alleviated oedema, proteinuria and foot process effacement. Triptolide also inhibited podocyte apoptosis in our zebrafish model and in vitro. We also examined the mechanism of triptolide protection of podocyte. Whole-genome expression profiles of cultured podocytes demonstrated that triptolide treatment downregulated apoptosis pathway-related GADD45B expression. Specific overexpression of gadd45b in zebrafish podocytes abolished the protective effects of triptolide. GADD45B is a mediator of podocyte apoptosis that contains typical NF-κB binding sites in the promoter region, and NF-κB p65 primarily transactivates this gene. Triptolide inhibited NF-κB signalling activation and binding of NF-κB to the GADD45B promoter. Taken together, our findings demonstrated that triptolide attenuated proteinuria and podocyte apoptosis via inhibition of NF-κB/GADD45B signalling, which provides a new understanding of the antiproteinuric effects of triptolide in glomerular diseases.
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Affiliation(s)
- Ling Wang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Liwen Zhang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Qing Hou
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Xiaodong Zhu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Zhaohong Chen
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China.
| | - Zhihong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China.
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15
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Estrella MM, Parekh RS. The Expanding Role of APOL1 Risk in Chronic Kidney Disease and Cardiovascular Disease. Semin Nephrol 2018; 37:520-529. [PMID: 29110759 DOI: 10.1016/j.semnephrol.2017.07.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Variants of the APOL1 gene, found primarily in individuals of African descent, are associated with various forms of kidney disease and kidney disease progression. Recent studies evaluating the association of APOL1 with cardiovascular disease have yielded conflicting results, and the potential role in cardiovascular disease remains unclear. In this review, we summarize the observational studies linking the APOL1 risk variants with chronic kidney and cardiovascular disease among persons of African descent.
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Affiliation(s)
- Michelle M Estrella
- Kidney Health Research Collaborative, Department of Medicine, University of California San Francisco, San Francisco, CA; Department of Medicine, San Francisco VA Medical Center, San Francisco, CA
| | - Rulan S Parekh
- Division of Nephrology, Departments of Pediatrics and Medicine, The Hospital for Sick Children, SickKids Research Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada.
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16
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Ashraf S, Kudo H, Rao J, Kikuchi A, Widmeier E, Lawson JA, Tan W, Hermle T, Warejko JK, Shril S, Airik M, Jobst-Schwan T, Lovric S, Braun DA, Gee HY, Schapiro D, Majmundar AJ, Sadowski CE, Pabst WL, Daga A, van der Ven AT, Schmidt JM, Low BC, Gupta AB, Tripathi BK, Wong J, Campbell K, Metcalfe K, Schanze D, Niihori T, Kaito H, Nozu K, Tsukaguchi H, Tanaka R, Hamahira K, Kobayashi Y, Takizawa T, Funayama R, Nakayama K, Aoki Y, Kumagai N, Iijima K, Fehrenbach H, Kari JA, El Desoky S, Jalalah S, Bogdanovic R, Stajić N, Zappel H, Rakhmetova A, Wassmer SR, Jungraithmayr T, Strehlau J, Kumar AS, Bagga A, Soliman NA, Mane SM, Kaufman L, Lowy DR, Jairajpuri MA, Lifton RP, Pei Y, Zenker M, Kure S, Hildebrandt F. Mutations in six nephrosis genes delineate a pathogenic pathway amenable to treatment. Nat Commun 2018; 9:1960. [PMID: 29773874 PMCID: PMC5958119 DOI: 10.1038/s41467-018-04193-w] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 04/07/2018] [Indexed: 02/06/2023] Open
Abstract
No efficient treatment exists for nephrotic syndrome (NS), a frequent cause of chronic kidney disease. Here we show mutations in six different genes (MAGI2, TNS2, DLC1, CDK20, ITSN1, ITSN2) as causing NS in 17 families with partially treatment-sensitive NS (pTSNS). These proteins interact and we delineate their roles in Rho-like small GTPase (RLSG) activity, and demonstrate deficiency for mutants of pTSNS patients. We find that CDK20 regulates DLC1. Knockdown of MAGI2, DLC1, or CDK20 in cultured podocytes reduces migration rate. Treatment with dexamethasone abolishes RhoA activation by knockdown of DLC1 or CDK20 indicating that steroid treatment in patients with pTSNS and mutations in these genes is mediated by this RLSG module. Furthermore, we discover ITSN1 and ITSN2 as podocytic guanine nucleotide exchange factors for Cdc42. We generate Itsn2-L knockout mice that recapitulate the mild NS phenotype. We, thus, define a functional network of RhoA regulation, thereby revealing potential therapeutic targets.
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Affiliation(s)
- Shazia Ashraf
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Hiroki Kudo
- Department of Pediatrics, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Jia Rao
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Atsuo Kikuchi
- Department of Pediatrics, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Eugen Widmeier
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jennifer A Lawson
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Weizhen Tan
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Tobias Hermle
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jillian K Warejko
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Shirlee Shril
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Merlin Airik
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Tilman Jobst-Schwan
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Svjetlana Lovric
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Daniela A Braun
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Heon Yung Gee
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - David Schapiro
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Amar J Majmundar
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Carolin E Sadowski
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Werner L Pabst
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ankana Daga
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Amelie T van der Ven
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Johanna M Schmidt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Boon Chuan Low
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Anjali Bansal Gupta
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Brajendra K Tripathi
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jenny Wong
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kirk Campbell
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kay Metcalfe
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Denny Schanze
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
| | - Tetsuya Niihori
- Department of Medical Genetics, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Hiroshi Kaito
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
| | - Hiroyasu Tsukaguchi
- 2nd Department of Internal Medicine, Kansai Medical University, 2-3-1 Shin-machi, Hirakata-shi, Osaka, 573-1191, Japan
| | - Ryojiro Tanaka
- Department of Nephrology, Hyogo Prefectural Kobe Children's Hospital, 1-6-7 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Kiyoshi Hamahira
- Department of Pediatrics, Himeji Red Cross Hospital, 1-12-1 Shimoteno, Himeji, Hyogo, 670-8540, Japan
| | - Yasuko Kobayashi
- Department of Pediatrics, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
- Academic Renal Unit, School of Clinical Science, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY, United Kingdom
| | - Takumi Takizawa
- Department of Pediatrics, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Ryo Funayama
- Division of Cell Proliferation, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
| | - Keiko Nakayama
- Division of Cell Proliferation, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
| | - Yoko Aoki
- Department of Medical Genetics, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Naonori Kumagai
- Department of Pediatrics, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
| | - Henry Fehrenbach
- Department of Pediatric Nephrology, Children's Hospital, Memmingen, Germany
| | - Jameela A Kari
- Pediatric Nephrology Center of Excellence and Pediatric Department, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sherif El Desoky
- Pediatric Nephrology Center of Excellence and Pediatric Department, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sawsan Jalalah
- Pathology Department, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Radovan Bogdanovic
- Institute for Mother and Child Health Care of Serbia "Dr Vukan Čupić", Department of Nephrology, University of Belgrade, Faculty of Medicine, Belgrade, 11000, Serbia
| | - Nataša Stajić
- Institute for Mother and Child Health Care of Serbia "Dr Vukan Čupić", Department of Nephrology, University of Belgrade, Faculty of Medicine, Belgrade, 11000, Serbia
| | - Hildegard Zappel
- Department for Paediatrics II, University of Göttingen, Göttingen, Germany
| | - Assel Rakhmetova
- Department of Nephrology, Asfendiyarov Kazakh National Medical University, Almaty, Kazakhstan
| | | | | | - Juergen Strehlau
- Department of Pediatric Nephrology, Hannover Medical School, Hannover, Germany
| | - Aravind Selvin Kumar
- Department of Pediatric Nephrology and Medical Genetics, Institute of Child Health and Hospital for Children, TN Dr.M.G.R. Medical University, Chennai, India
| | - Arvind Bagga
- Division of Pediatric Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - Neveen A Soliman
- Department of Pediatrics, Center of Pediatric Nephrology & Transplantation, Kasr Al Ainy School of Medicine, Cairo University, Cairo, Egypt
| | - Shrikant M Mane
- Department of Genetics, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Lewis Kaufman
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Douglas R Lowy
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | | | - Richard P Lifton
- Department of Genetics, Yale University School of Medicine, New Haven, CT, 06510, USA
- Laboratory of Human Genetics and Genomics, The Rockefeller University, New York, NY, 10065, USA
| | - York Pei
- Division of Nephrology, University Health Network, and University of Toronto, Toronto, ON, Canada
| | - Martin Zenker
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
| | - Shigeo Kure
- Department of Pediatrics, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan.
| | - Friedhelm Hildebrandt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
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17
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Zhao X, Hwang DY, Kao HY. The Role of Glucocorticoid Receptors in Podocytes and Nephrotic Syndrome. NUCLEAR RECEPTOR RESEARCH 2018; 5. [PMID: 30417008 PMCID: PMC6224173 DOI: 10.11131/2018/101323] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Glucocorticoid receptor (GC), a founding member of the nuclear hormone receptor superfamily, is a glucocorticoid-activated transcription factor that regulates gene expression and controls the development and homeostasis of human podocytes. Synthetic glucocorticoids are the standard treatment regimens for proteinuria (protein in the urine) and nephrotic syndrome (NS) caused by kidney diseases. These include minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MN) and immunoglobulin A nephropathy (IgAN) or subsequent complications due to diabetes mellitus or HIV infection. However, unwanted side effects and steroid-resistance remain major issues for their long-term use. Furthermore, the mechanism by which glucocorticoids elicit their renoprotective activity in podocyte and glomeruli is poorly understood. Podocytes are highly differentiated epithelial cells that contribute to the integrity of kidney glomerular filtration barrier. Injury or loss of podocytes leads to proteinuria and nephrotic syndrome. Recent studies in multiple experimental models have begun to explore the mechanism of GC action in podocytes. This review will discuss progress in our understanding of the role of glucocorticoid receptor and glucocorticoids in podocyte physiology and their renoprotective activity in nephrotic syndrome.
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Affiliation(s)
- Xuan Zhao
- Department of Biochemistry, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, USA
| | - Daw-Yang Hwang
- Division of Nephrology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Hung-Ying Kao
- Department of Biochemistry, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, USA
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18
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Endlich N, Kliewe F, Kindt F, Schmidt K, Kotb AM, Artelt N, Lindenmeyer MT, Cohen CD, Döring F, Kuss AW, Amann K, Moeller MJ, Kabgani N, Blumenthal A, Endlich K. The transcription factor Dach1 is essential for podocyte function. J Cell Mol Med 2018; 22:2656-2669. [PMID: 29498212 PMCID: PMC5908116 DOI: 10.1111/jcmm.13544] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 12/24/2017] [Indexed: 12/27/2022] Open
Abstract
Dedifferentiation and loss of podocytes are the major cause of chronic kidney disease. Dach1, a transcription factor that is essential for cell fate, was found in genome‐wide association studies to be associated with the glomerular filtration rate. We found that podocytes express high levels of Dach1 in vivo and to a much lower extent in vitro. Parietal epithelial cells (PECs) that are still under debate to be a type of progenitor cell for podocytes expressed Dach1 only at low levels. The transfection of PECs with a plasmid encoding for Dach1 induced the expression of synaptopodin, a podocyte‐specific protein, demonstrated by immunocytochemistry and Western blot. Furthermore, synaptopodin was located along actin fibres in a punctate pattern in Dach1‐expressing PECs comparable with differentiated podocytes. Moreover, dedifferentiating podocytes of isolated glomeruli showed a significant reduction in the expression of Dach1 together with synaptopodin after 9 days in cell culture. To study the role of Dach1 in vivo, we used the zebrafish larva as an animal model. Knockdown of the zebrafish ortholog Dachd by morpholino injection into fertilized eggs resulted in a severe renal phenotype. The glomeruli of the zebrafish larvae showed morphological changes of the glomerulus accompanied by down‐regulation of nephrin and leakage of the filtration barrier. Interestingly, glomeruli of biopsies from patients suffering from diabetic nephropathy showed also a significant reduction of Dach1 and synaptopodin in contrast to control biopsies. Taken together, Dach1 is a transcription factor that is important for podocyte differentiation and proper kidney function.
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Affiliation(s)
- Nicole Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Felix Kliewe
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Frances Kindt
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Katharina Schmidt
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Ahmed M Kotb
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany.,Department of Anatomy and Histology, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
| | - Nadine Artelt
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Maja T Lindenmeyer
- Nephrological Center, Medical Clinic and Policlinic IV, University of Munich, Munich, Germany
| | - Clemens D Cohen
- Nephrological Center, Medical Clinic and Policlinic IV, University of Munich, Munich, Germany
| | - Franziska Döring
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Andreas W Kuss
- Department of Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Kerstin Amann
- Department of Nephropathology, Institute of Pathology, University Hospital Erlangen, Erlangen, Germany
| | - Marcus J Moeller
- Department of Internal Medicine II, Nephrology and Clinical Immunology, RWTH Aachen University Hospital, Aachen, Germany
| | - Nazanin Kabgani
- Department of Internal Medicine II, Nephrology and Clinical Immunology, RWTH Aachen University Hospital, Aachen, Germany
| | - Antje Blumenthal
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Karlhans Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
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19
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Rao J, Ashraf S, Tan W, van der Ven AT, Gee HY, Braun DA, Fehér K, George SP, Esmaeilniakooshkghazi A, Choi WI, Jobst-Schwan T, Schneider R, Schmidt JM, Widmeier E, Warejko JK, Hermle T, Schapiro D, Lovric S, Shril S, Daga A, Nayir A, Shenoy M, Tse Y, Bald M, Helmchen U, Mir S, Berdeli A, Kari JA, El Desoky S, Soliman NA, Bagga A, Mane S, Jairajpuri MA, Lifton RP, Khurana S, Martins JC, Hildebrandt F. Advillin acts upstream of phospholipase C ϵ1 in steroid-resistant nephrotic syndrome. J Clin Invest 2017; 127:4257-4269. [PMID: 29058690 DOI: 10.1172/jci94138] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 09/19/2017] [Indexed: 11/17/2022] Open
Abstract
Steroid-resistant nephrotic syndrome (SRNS) is a frequent cause of chronic kidney disease. Here, we identified recessive mutations in the gene encoding the actin-binding protein advillin (AVIL) in 3 unrelated families with SRNS. While all AVIL mutations resulted in a marked loss of its actin-bundling ability, truncation of AVIL also disrupted colocalization with F-actin, thereby leading to impaired actin binding and severing. Additionally, AVIL colocalized and interacted with the phospholipase enzyme PLCE1 and with the ARP2/3 actin-modulating complex. Knockdown of AVIL in human podocytes reduced actin stress fibers at the cell periphery, prevented recruitment of PLCE1 to the ARP3-rich lamellipodia, blocked EGF-induced generation of diacylglycerol (DAG) by PLCE1, and attenuated the podocyte migration rate (PMR). These effects were reversed by overexpression of WT AVIL but not by overexpression of any of the 3 patient-derived AVIL mutants. The PMR was increased by overexpression of WT Avil or PLCE1, or by EGF stimulation; however, this increased PMR was ameliorated by inhibition of the ARP2/3 complex, indicating that ARP-dependent lamellipodia formation occurs downstream of AVIL and PLCE1 function. Together, these results delineate a comprehensive pathogenic axis of SRNS that integrates loss of AVIL function with alterations in the action of PLCE1, an established SRNS protein.
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Affiliation(s)
- Jia Rao
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Nephrology, Children's Hospital of Fudan University, Shanghai, China
| | - Shazia Ashraf
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Weizhen Tan
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Amelie T van der Ven
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Heon Yung Gee
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Daniela A Braun
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Krisztina Fehér
- NMR and Structure Analysis Group, Department of Organic and Macromolecular Chemistry, University of Gent, Gent, Belgium
| | - Sudeep P George
- Department of Biology and Biochemistry, University of Houston, Houston,Texas, USA
| | | | - Won-Il Choi
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Tilman Jobst-Schwan
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ronen Schneider
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Johanna Magdalena Schmidt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Eugen Widmeier
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jillian K Warejko
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Tobias Hermle
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - David Schapiro
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Svjetlana Lovric
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Shirlee Shril
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ankana Daga
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ahmet Nayir
- Department of Pediatric Nephrology, Faculty of Medicine, University of Istanbul, Istanbul, Turkey
| | - Mohan Shenoy
- Department of Pediatric Nephrology, Royal Manchester Children's Hospital, Manchester, United Kingdom
| | - Yincent Tse
- Department of Pediatric Nephrology, Great North Children's Hospital, Newcastle Upon Tyne, United Kingdom
| | - Martin Bald
- Olga Children's Hospital, Clinic Stuttgart, Stuttgart, Germany
| | - Udo Helmchen
- Institute of Pathology, Kidney Registry, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Sevgi Mir
- Department of Pediatrics, Molecular Medicine Laboratory, Ege University, Izmir, Turkey
| | - Afig Berdeli
- Department of Pediatrics, Molecular Medicine Laboratory, Ege University, Izmir, Turkey
| | - Jameela A Kari
- Pediatric Nephrology Center of Excellence and Pediatric Department, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sherif El Desoky
- Pediatric Nephrology Center of Excellence and Pediatric Department, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Neveen A Soliman
- Department of Pediatrics, Center of Pediatric Nephrology and Transplantation, Kasr Al Ainy School of Medicine, Cairo University, Cairo, Egypt
| | - Arvind Bagga
- Division of Pediatric Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - Shrikant Mane
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
| | | | - Richard P Lifton
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
| | - Seema Khurana
- Department of Biology and Biochemistry, University of Houston, Houston,Texas, USA.,Baylor College of Medicine, Houston, Texas, USA
| | - Jose C Martins
- NMR and Structure Analysis Group, Department of Organic and Macromolecular Chemistry, University of Gent, Gent, Belgium
| | - Friedhelm Hildebrandt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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20
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Chen YH, Lin WW, Liu CS, Su SL. H2O2 induces caveolin‑1 degradation and impaired mitochondrial function in E11 podocytes. Mol Med Rep 2017; 16:7841-7847. [PMID: 28944844 DOI: 10.3892/mmr.2017.7497] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 06/28/2017] [Indexed: 11/05/2022] Open
Abstract
Increased intercellular reactive oxygen species (ROS) levels are the major cause of podocyte injury with proteinuria. Caveolin‑1 (CAV‑1) is an essential protein component of caveolae. CAV‑1 participates in signal transduction and endocytic trafficking. Recent research has indicated that CAV‑1 regulates oxidative stress‑induced pathways. The present study used hydrogen peroxide (H2O2) at nontoxic concentrations to elevate the level of ROS in E11 podocytes. Treatment with 500 and 1,000 µM H2O2 for 1 h significantly reduced CAV‑1 expression levels. Simultaneously, the treatment significantly reduced the expression of the antioxidant enzymes glutamine‑cysteine ligase catalytic subunit, superoxide dismutase 2 and catalase. To determine the role of CAV‑1 in mediating oxidative stress, E11 podocytes were administered antenapedia‑CAV‑1 (AP‑CAV‑1) peptide for 48 h. The AP‑CAV‑1 treatment enhanced CAV‑1 expression and inhibited cyclophilin A expression, thus reducing ROS‑induced inflammation. Moreover, CAV‑1 protected against H2O2‑induced oxidative stress responses by enhancing the expression of antioxidant enzymes. Furthermore, CAV‑1 attenuated H2O2‑induced changes oxidative phosphorylation, and the expression of optic atrophy 1 and translocase of the inner membrane 23, as well as preserving mitochondrial function. CAV‑1 treatment significantly suppressed apoptosis, as indicated by a higher B‑cell lymphoma 2/BCL2‑associated X protein ratio. Therefore, enhancing the expression of CAV‑1 may be an important therapeutic consideration in treating podocyte injury.
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Affiliation(s)
- Ya-Hui Chen
- Vascular and Genomic Center, Changhua Christian Hospital, Changhua 50094, P.R. China
| | - Wei-Wen Lin
- Division of Cardiovascular Center, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung 40705, P.R. China
| | - Chin-San Liu
- Vascular and Genomic Center, Changhua Christian Hospital, Changhua 50094, P.R. China
| | - Shih-Li Su
- Vascular and Genomic Center, Changhua Christian Hospital, Changhua 50094, P.R. China
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21
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Karp AM, Gbadegesin RA. Genetics of childhood steroid-sensitive nephrotic syndrome. Pediatr Nephrol 2017; 32:1481-1488. [PMID: 27470160 PMCID: PMC5276801 DOI: 10.1007/s00467-016-3456-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 06/27/2016] [Accepted: 06/29/2016] [Indexed: 02/07/2023]
Abstract
The pathogenesis of childhood-onset nephrotic syndrome (NS), disparity in incidence of NS among races, and variable responses to therapies in children with NS have defied explanation to date. In the last 20 years over 50 genetic causes of steroid-resistant nephrotic syndrome (SRNS) have been identified, and at least two disease loci for two pathologic variants of SRNS (focal segmental glomerulosclerosis and membranous nephropathy) have been defined. However, the genetic causes and risk loci for steroid-sensitive nephrotic syndrome (SSNS) remain elusive, partly because SSNS is relatively rare and also because cases of SSNS vary widely in phenotypic expression over time. A recent study of a well-defined modest cohort of children with SSNS identified variants in HLA-DQA1 as a risk factor for SSNS. Here we review what is currently known about the genetics of SSNS and also discuss how recent careful phenotypic and genomic studies reinforce the role of adaptive immunity in the molecular mechanisms of SSNS.
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Affiliation(s)
- Alana M. Karp
- Department of Pediatrics, Division of Nephrology, Emory University, Atlanta, GA, USA
| | - Rasheed A. Gbadegesin
- Department of Pediatrics, Division of Nephrology, Duke University Medical Center, Durham, NC,Duke Molecular Physiology Institute, Duke University, Durham, NC,To whom correspondence should be addressed:
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22
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Siegerist F, Zhou W, Endlich K, Endlich N. 4D in vivo imaging of glomerular barrier function in a zebrafish podocyte injury model. Acta Physiol (Oxf) 2017; 220:167-173. [PMID: 27414464 DOI: 10.1111/apha.12754] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 06/27/2016] [Accepted: 07/10/2016] [Indexed: 01/15/2023]
Abstract
AIM Zebrafish larvae with their simplified pronephros are an ideal model to study glomerular physiology. Although several groups use zebrafish larvae to assess glomerular barrier function, temporary or slight changes are still difficult to measure. The aim of this study was to investigate the potential of in vivo two-photon microscopy (2-PM) for long-term imaging of glomerular barrier function in zebrafish larvae. METHODS As a proof of principle, we adapted the nitroreductase/metronidazole model of targeted podocyte ablation for 2-PM. Combination with a strain, which expresses eGFP-vitamin D-binding protein in the blood plasma, led to a strain that allowed induction of podocyte injury with parallel assessment of glomerular barrier function. We used four-dimensional (4D) 2-PM to assess eGFP fluorescence over 26 h in the vasculature and in tubules of multiple zebrafish larvae (5 days post-fertilization) simultaneously. RESULTS By 4D 2-PM, we observed that, under physiological conditions, eGFP fluorescence was retained in the vasculature and rarely detected in proximal tubule cells. Application of metronidazole induced podocyte injury and cell death as shown by TUNEL staining. Induction of podocyte injury resulted in a dramatic decrease of eGFP fluorescence in the vasculature over time (about 50% and 90% after 2 and 12 h respectively). Loss of vascular eGFP fluorescence was paralleled by an endocytosis-mediated accumulation of eGFP fluorescence in proximal tubule cells, indicating proteinuria. CONCLUSION We established a microscopy-based method to monitor the dynamics of glomerular barrier function during induction of podocyte injury in multiple zebrafish larvae simultaneously over 26 h.
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Affiliation(s)
- F. Siegerist
- Department of Anatomy and Cell Biology; University Medicine Greifswald; Greifswald Germany
| | - W. Zhou
- Department of Pediatrics and Communicable Diseases; University of Michigan; Ann Arbor MI USA
| | - K. Endlich
- Department of Anatomy and Cell Biology; University Medicine Greifswald; Greifswald Germany
| | - N. Endlich
- Department of Anatomy and Cell Biology; University Medicine Greifswald; Greifswald Germany
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23
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Siegerist F, Blumenthal A, Zhou W, Endlich K, Endlich N. Acute podocyte injury is not a stimulus for podocytes to migrate along the glomerular basement membrane in zebrafish larvae. Sci Rep 2017; 7:43655. [PMID: 28252672 PMCID: PMC5333633 DOI: 10.1038/srep43655] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 01/26/2017] [Indexed: 12/28/2022] Open
Abstract
Podocytes have a unique 3D structure of major and interdigitating foot processes which is the prerequisite for renal blood filtration. Loss of podocytes leads to chronic kidney disease ending in end stage renal disease. Until now, the question if podocytes can be replaced by immigration of cells along the glomerular basement membrane (GBM) is under debate. We recently showed that in contrast to former theories, podocytes are stationary in the zebrafish pronephros and neither migrate nor change their branching pattern of major processes over 23 hours. However, it was still unclear whether podocytes are able to migrate during acute injury. To investigate this, we applied the nitroreductase/metronidazole zebrafish model of podocyte injury to in vivo two-photon microscopy. The application of metronidazole led to retractions of major processes associated with a reduced expression of podocyte-specific proteins and a formation of subpodocyte pseudocyst. Electron microscopy showed that broad areas of the capillaries became denuded. By 4D in vivo observation of single podocytes, we could show that the remaining podocytes did not walk along GBM during 24 h. This in vivo study reveals that podocytes are very stationary cells making regenerative processes by podocyte walking along the GBM very unlikely.
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Affiliation(s)
- Florian Siegerist
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Antje Blumenthal
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Weibin Zhou
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan, USA
| | - Karlhans Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Nicole Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
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24
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Abstract
PURPOSE OF REVIEW Diabetic nephropathy, a major microvascular complication of diabetes and the most common cause of end-stage renal disease, is characterized by prominent accumulation of extracellular matrix. The membrane microdomains caveolae, and their integral protein caveolin-1, play critical roles in the regulation of signal transduction. In this review we discuss current knowledge of the contribution of caveolin-1/caveolae to profibrotic signaling and the pathogenesis of diabetic kidney disease, and assess its potential as a therapeutic target. RECENT FINDINGS Caveolin (cav)-1 is key to facilitating profibrotic signal transduction induced by several stimuli known to be pathogenic in diabetic nephropathy, including the most prominent factors hyperglycemia and angiotensin II. Phosphorylation of cav-1 on Y14 is an important regulator of these responses. In vivo studies support a pathogenic role for caveolae in the progression of diabetic nephropathy. Targeting caveolin-1/caveolae would enable inhibition of multiple profibrotic pathways, representing a novel and potentially potent therapeutic option for diabetic nephropathy.
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Affiliation(s)
- Richard Van Krieken
- Department of Medicine, Division of Nephrology, St. Joseph's Hospital, McMaster University, 50 Charlton Ave E, T3311, Hamilton, ON, L8N 4A6, Canada
| | - Joan C Krepinsky
- Department of Medicine, Division of Nephrology, St. Joseph's Hospital, McMaster University, 50 Charlton Ave E, T3311, Hamilton, ON, L8N 4A6, Canada.
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25
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Minimal change disease and idiopathic FSGS: manifestations of the same disease. Nat Rev Nephrol 2016; 12:768-776. [DOI: 10.1038/nrneph.2016.147] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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26
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GADD45B mediates podocyte injury in zebrafish by activating the ROS-GADD45B-p38 pathway. Cell Death Dis 2016; 7:e2068. [PMID: 26794661 PMCID: PMC4816163 DOI: 10.1038/cddis.2015.300] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/25/2015] [Accepted: 09/10/2015] [Indexed: 12/17/2022]
Abstract
GADD45 gene has been implicated in cell cycle arrest, cell survival or apoptosis in a cell type specific and context-dependent manner. Members of GADD45 gene family have been found differentially expressed in several podocyte injury models, but their roles in podocytes are unclear. Using an in vivo zebrafish model of inducible podocyte injury that we have previously established, we found that zebrafish orthologs of gadd45b were induced upon the induction of podocyte injury. Podocyte-specific overexpression of zebrafish gadd45b exacerbated edema, proteinuria and foot-process effacement, whereas knockdown of gadd45b by morpholino-oligos in zebrafish larvae ameliorated podocyte injury. We then explored the role of GADD45B induction in podocyte injury using in vitro podocyte culture. We confirmed that GADD45B was significantly upregulated during the early phase of podocyte injury in cultured human podocytes and that podocyte apoptosis induced by TGF-β and puromycin aminonucleoside (PAN) was aggravated by GADD45B overexpression but ameliorated by shRNA-mediated GADD45B knockdown. We also showed that ROS inhibitor NAC suppressed PAN-induced GADD45B expression and subsequent activation of p38 MAPK pathway in podocytes and that inhibition of GADD45B diminished PAN-induced p38 MAPK activation. Taken together, our findings demonstrated that GADD45B has an important role in podocyte injury and may be a therapeutic target for the management of podocyte injury in glomerular diseases.
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27
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Wan X, Lee MS, Zhou W. Dosage-dependent role of Rac1 in podocyte injury. Am J Physiol Renal Physiol 2016; 310:F777-F784. [PMID: 26792065 DOI: 10.1152/ajprenal.00381.2015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 01/19/2016] [Indexed: 01/03/2023] Open
Abstract
Activation of small GTPase Rac1 in podocytes is associated with rodent models of kidney injury and familial nephrotic syndrome. Induced Rac1 activation in podocytes in transgenic mice results in rapid transient proteinuria and foot process effacement, but not glomerular sclerosis. Thus it remains an open question whether abnormal activation of Rac1 in podocytes is sufficient to cause permanent podocyte damage. Using a number of transgenic zebrafish models, we showed that moderate elevation of Rac1 activity in podocytes did not impair the glomerular filtration barrier but aggravated metronidazole-induced podocyte injury, while inhibition of Rac1 activity ameliorated metronidazole-induced podocyte injury. Furthermore, a further increase in Rac1 activity in podocytes was sufficient to cause proteinuria and foot process effacement, which resulted in edema and lethality in juvenile zebrafish. We also found that activation of Rac1 in podocytes significantly downregulated the expression of nephrin and podocin, suggesting an adverse effect of Rac1 on slit diaphragm protein expression. Taken together, our data have demonstrated a causal link between excessive Rac1 activity and podocyte injury in a dosage-dependent manner, and transgenic zebrafish of variable Rac1 activities in podocytes may serve as useful animal models for the study of Rac1-related podocytopathy.
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Affiliation(s)
- Xiaoyang Wan
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan
| | - Mi-Sun Lee
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan
| | - Weibin Zhou
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan
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28
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Lovric S, Ashraf S, Tan W, Hildebrandt F. Genetic testing in steroid-resistant nephrotic syndrome: when and how? Nephrol Dial Transplant 2015; 31:1802-1813. [PMID: 26507970 DOI: 10.1093/ndt/gfv355] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 09/08/2015] [Indexed: 01/15/2023] Open
Abstract
Steroid-resistant nephrotic syndrome (SRNS) represents the second most frequent cause of chronic kidney disease in the first three decades of life. It manifests histologically as focal segmental glomerulosclerosis (FSGS) and carries a 33% risk of relapse in a renal transplant. No efficient treatment exists. Identification of single-gene (monogenic) causes of SRNS has moved the glomerular epithelial cell (podocyte) to the center of its pathogenesis. Recently, mutations in >30 recessive or dominant genes were identified as causing monogenic forms of SRNS, thereby revealing the encoded proteins as essential for glomerular function. These findings helped define protein interaction complexes and functional pathways that could be targeted for treatment of SRNS. Very recently, it was discovered that in the surprisingly high fraction of ∼30% of all individuals who manifest with SRNS before 25 years of age, a causative mutation can be detected in one of the ∼30 different SRNS-causing genes. These findings revealed that SRNS and FSGS are not single disease entities but rather are part of a spectrum of distinct diseases with an identifiable genetic etiology. Mutation analysis should be offered to all individuals who manifest with SRNS before the age of 25 years, because (i) it will provide the patient and families with an unequivocal cause-based diagnosis, (ii) it may uncover a form of SRNS that is amenable to treatment (e.g. coenzyme Q10), (iii) it may allow avoidance of a renal biopsy procedure, (iv) it will further unravel the puzzle of pathogenic pathways of SRNS and (v) it will permit personalized treatment options for SRNS, based on genetic causation in way of 'precision medicine'.
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Affiliation(s)
- Svjetlana Lovric
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Shazia Ashraf
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Weizhen Tan
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Friedhelm Hildebrandt
- Division of Nephrology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA
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