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Zhang K, Fu Z, Zhang Y, Chen X, Cai G, Hong Q. The role of cellular crosstalk in the progression of diabetic nephropathy. Front Endocrinol (Lausanne) 2023; 14:1173933. [PMID: 37538798 PMCID: PMC10395826 DOI: 10.3389/fendo.2023.1173933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 06/26/2023] [Indexed: 08/05/2023] Open
Abstract
Diabetic nephropathy (DN) is one of the most common complications of diabetes, and its main manifestations are progressive proteinuria and abnormal renal function, which eventually develops end stage renal disease (ESRD). The pathogenesis of DN is complex and involves many signaling pathways and molecules, including metabolic disorders, genetic factors, oxidative stress, inflammation, and microcirculatory abnormalities strategies. With the development of medical experimental techniques, such as single-cell transcriptome sequencing and single-cell proteomics, the pathological alterations caused by kidney cell interactions have attracted more and more attention. Here, we reviewed the characteristics and related mechanisms of crosstalk among kidney cells podocytes, endothelial cells, mesangial cells, pericytes, and immune cells during the development and progression of DN and highlighted its potential therapeutic effects.
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Glomerular Endothelial Cell-Derived miR-200c Impairs Glomerular Homeostasis by Targeting Podocyte VEGF-A. Int J Mol Sci 2022; 23:ijms232315070. [PMID: 36499397 PMCID: PMC9735846 DOI: 10.3390/ijms232315070] [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: 09/02/2022] [Revised: 11/27/2022] [Accepted: 11/29/2022] [Indexed: 12/04/2022] Open
Abstract
Deciphering the pathophysiological mechanisms of primary podocytopathies that can lead to end-stage renal disease and increased mortality is an unmet need. Studying how microRNAs (miRs) interfere with various signaling pathways enables identification of pathomechanisms, novel biomarkers and potential therapeutic options. We investigated the expression of miR-200c in urine from patients with different renal diseases as a potential candidate involved in podocytopathies. The role of miR-200c for the glomerulus and its potential targets were studied in cultured human podocytes, human glomerular endothelial cells and in the zebrafish model. miR-200c was upregulated in urine from patients with minimal change disease, membranous glomerulonephritis and focal segmental glomerulosclerosis and also in transforming growth factor beta (TGF-β) stressed glomerular endothelial cells, but not in podocytes. In zebrafish, miR-200c overexpression caused proteinuria, edema, podocyte foot process effacement and glomerular endotheliosis. Although zinc finger E-Box binding homeobox 1/2 (ZEB1/2), important in epithelial to mesenchymal transition (EMT), are prominent targets of miR-200c, their downregulation did not explain our zebrafish phenotype. We detected decreased vegfaa/bb in zebrafish overexpressing miR-200c and could further prove that miR-200c decreased VEGF-A expression and secretion in cultured human podocytes. We hypothesize that miR-200c is released from glomerular endothelial cells during cell stress and acts in a paracrine, autocrine, as well as context-dependent manner in the glomerulus. MiR-200c can cause glomerular damage most likely due to the reduction of podocyte VEGF-A. In contrast, miR-200c might also influence ZEB expression and therefore EMT, which might be important in other conditions. Therefore, we propose that miR-200c-mediated effects in the glomerulus are context-sensitive.
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Bai M, Zhang J, Su X, Yao X, Li H, Cheng J, Mao J, Li X, Chen J, Lin W. Serum IL-12p40: A novel biomarker for early prediction of minimal change disease relapse following glucocorticoids therapy. Front Med (Lausanne) 2022; 9:922193. [PMID: 36507530 PMCID: PMC9729255 DOI: 10.3389/fmed.2022.922193] [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: 04/17/2022] [Accepted: 11/02/2022] [Indexed: 11/27/2022] Open
Abstract
Background Minimal change disease (MCD) has a high recurrence rate, but currently, no biomarker can predict its recurrence. To this end, this study aimed at identifying potential serum cytokines as valuable biomarkers for predicting the risk of MCD recurrence. Materials and methods Raybiotech 440 cytokine antibody microarray was used to detect the serum samples of eight relapsed, eight non-relapsed MCD patients after glucocorticoid treatment, and eight healthy controls. The differentially expressed cytokines were confirmed by enzyme-linked immunosorbent assay (ELISA) with serum samples from 29 non-relapsed and 35 relapsed MCD patients. The study used the receiver operating characteristic (ROC) curve analysis to investigate the sensitivity and specificity of a serum biomarker for predicting the MCD relapse. Results Serum IL-12p40 levels increased significantly in the relapsed group. The Area Under the ROC Curve (AUC) of IL-12p40 was 0.727 (95%CI: 0.597-0.856; P < 0.01). The RNA-sequencing analysis and qPCR assay performed on the IL-12 treated mouse podocytes and the control group showed increased expression of podocyte damage genes, such as connective tissue growth factor (CTGF), matrix metallopeptidase 9 (MMP9), secreted phosphoprotein 1 (SPP1), and cyclooxygenase-2 (COX-2) in the former group. Conclusion IL-12p40 may serve as a new biomarker for predicting the risk of MCD recurrence after glucocorticoid treatment, and it may be involved in the pathogenesis and recurrence of MCD.
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Affiliation(s)
- Mengqiu Bai
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,Department of Nephrology, The Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Jinhua, Zhejiang, China,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jian Zhang
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xinwan Su
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,Department of Nephrology, The Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Jinhua, Zhejiang, China
| | - Xi Yao
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Heng Li
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jun Cheng
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jianhua Mao
- Department of Nephrology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xiayu Li
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,Xiayu Li,
| | - Jianghua Chen
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,Jianghua Chen,
| | - Weiqiang Lin
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,Department of Nephrology, The Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Jinhua, Zhejiang, China,*Correspondence: Weiqiang Lin,
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BECLIN1 Is Essential for Podocyte Secretory Pathways Mediating VEGF Secretion and Podocyte-Endothelial Crosstalk. Int J Mol Sci 2022; 23:ijms23073825. [PMID: 35409185 PMCID: PMC8998849 DOI: 10.3390/ijms23073825] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 03/17/2022] [Accepted: 03/29/2022] [Indexed: 02/06/2023] Open
Abstract
Vascular endothelial growth factor A (VEGFA) secretion from podocytes is crucial for maintaining endothelial integrity within the glomerular filtration barrier. However, until now, the molecular mechanisms underlying podocyte secretory function remained unclear. Through podocyte-specific deletion of BECLIN1 (ATG6 or Becn1), a key protein in autophagy initiation, we identified a major role for this molecule in anterograde Golgi trafficking. The Becn1-deficient podocytes displayed aberrant vesicle formation in the trans-Golgi network (TGN), leading to dramatic vesicle accumulation and complex disrupted patterns of intracellular vesicle trafficking and membrane dynamics. Phenotypically, podocyte-specific deletion of Becn1 resulted in early-onset glomerulosclerosis, which rapidly progressed and dramatically reduced mouse life span. Further, in vivo and in vitro studies clearly showed that VEGFA secretion, and thereby endothelial integrity, greatly depended on BECLIN1 availability and function. Being the first to demonstrate the importance of a secretory pathway for podocyte integrity and function, we identified BECLIN1 as a key component in this complex cellular process. Functionally, by promoting VEGFA secretion, a specific secretory pathway emerged as an essential component for the podocyte-endothelial crosstalk that maintains the glomerular filtration barrier.
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Role of Endothelial Glucocorticoid Receptor in the Pathogenesis of Kidney Diseases. Int J Mol Sci 2021; 22:ijms222413295. [PMID: 34948091 PMCID: PMC8706765 DOI: 10.3390/ijms222413295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/05/2021] [Accepted: 12/07/2021] [Indexed: 01/12/2023] Open
Abstract
Glucocorticoids, as multifunctional hormones, are widely used in the treatment of various diseases including nephrological disorders. They are known to affect immunological cells, effectively treating many autoimmune and inflammatory processes. Furthermore, there is a growing body of evidence demonstrating the potent role of glucocorticoids in non-immune cells such as podocytes. Moreover, novel data show additional pathways and processes affected by glucocorticoids, such as the Wnt pathway or autophagy. The endothelium is currently considered as a key organ in the regulation of numerous kidney functions such as glomerular filtration, vascular tone and the regulation of inflammation and coagulation. In this review, we analyse the literature concerning the effects of endothelial glucocorticoid receptor signalling on kidney function in health and disease, with special focus on hypertension, diabetic kidney disease, glomerulopathies and chronic kidney disease. Recent studies demonstrate the potential role of endothelial GR in the prevention of fibrosis of kidney tissue and cell metabolism through Wnt pathways, which could have a protective effect against disease progression. Another important aspect covered in this review is blood pressure regulation though GR and eNOS. We also briefly cover potential therapies that might affect the endothelial glucocorticoid receptor and its possible clinical implications, with special interest in selective or local GR stimulation and potential mitigation of GC treatment side effects.
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Ruslie RH, Darmadi D, Siregar GA. Vascular Endothelial Growth Factor (VEGF) and Neopterin Levels in Children with Steroid-sensitive and Steroid-resistant Nephrotic Syndrome. Med Arch 2021; 75:133-137. [PMID: 34219873 PMCID: PMC8228650 DOI: 10.5455/medarh.2021.75.133-137] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 04/20/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The most common glomerular disease in children is nephrotic syndrome. Steroid-resistant nephrotic syndrome tends to have a worse disease course, which bears a significant risk of chronic kidney disease in children. OBJECTIVE To compare VEGF and neopterin levels between children with steroid-sensitive nephrotic syndrome (SSNS), steroid-resistant nephrotic syndrome (SRNS), and also healthy (control) children. METHODS This cross-sectional study was conducted at H. Adam Malik General Hospital, Indonesia from January to December 2018. There were 160 children aged 1 to 8 years with confirmed nephrotic syndrome and without end-stage renal disease and systemic diseases, divided into SSNS, SRNS, and control groups. Data regarding age, gender, urine albumin creatinine ratio (UACR), serum albumin, total cholesterol, urea, creatinine, VEGF, and neopterin levels were collected. A p-value of less than 0.05 is considered statistically significant. RESULTS There were no differences between groups in gender (p = 0.269) and age (p = 0.375), but there was significant difference of UACR, albumin level, total cholesterol level, and VEGF level between groups, (all p< 0.001). There was a moderate positive correlation between VEGF level and UACR (r(158) = 0.439, p< 0.001) and a moderate negative correlation between neopterin level and albumin level (r(158)= -0.312, p = 0.005). CONCLUSION There were no differences in serum VEGF and neopterin levels between steroid-sensitive and steroid-resistant nephrotic syndrome groups. Serum VEGF level was positively correlated with UACR while serum neopterin level was negatively correlated with serum albumin level.
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Affiliation(s)
- Riska Habriel Ruslie
- Department of Child Health, Faculty of Medicine, Universitas Prima Indonesia, Medan, Indonesia
| | - Darmadi Darmadi
- Department of Internal Medicine, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia
| | - Gontar Alamsyah Siregar
- Department of Internal Medicine, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia
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Li Q, Gulati A, Lemaire M, Nottoli T, Bale A, Tufro A. Rho-GTPase Activating Protein myosin MYO9A identified as a novel candidate gene for monogenic focal segmental glomerulosclerosis. Kidney Int 2021; 99:1102-1117. [PMID: 33412162 DOI: 10.1016/j.kint.2020.12.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 12/04/2020] [Accepted: 12/10/2020] [Indexed: 01/18/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS) is a podocytopathy leading to kidney failure, whose molecular cause frequently remains unresolved. Here, we describe a rare MYO9A loss of function nonsense heterozygous mutation (p.Arg701∗) as a possible contributor to disease in a sibling pair with familial FSGS/proteinuria. MYO9A variants of uncertain significance were identified by whole exome sequencing in a cohort of 94 biopsy proven patients with FSGS. MYO9A is an unconventional myosin with a Rho-GAP domain that controls epithelial cell junction assembly, crosslinks and bundles actin and deactivates the small GTPase protein encoded by the RHOA gene. RhoA activity is associated with cytoskeleton regulation of actin stress fiber formation and actomyosin contractility. Myo9A was detected in mouse and human podocytes in vitro and in vivo. Knockin mice carrying the p.Arg701∗MYO9A (Myo9AR701X) generated by gene editing developed proteinuria, podocyte effacement and FSGS. Kidneys and podocytes from Myo9AR701X/+ mutant mice revealed Myo9A haploinsufficiency, increased RhoA activity, decreased Myo9A-actin-calmodulin interaction, impaired podocyte attachment and migration. Our results indicate that Myo9A is a novel component of the podocyte cytoskeletal apparatus that regulates RhoA activity and podocyte function. Thus, Myo9AR701X/+ knock-in mice recapitulate the proband FSGS phenotype, demonstrate that p.R701X Myo9A is an FSGS-causing mutation in mice and suggest that heterozygous loss-of-function MYO9A mutations may cause a novel form of human autosomal dominant FSGS. Hence, identification of MYO9A pathogenic variants in additional individuals with familial or sporadic FSGS is needed to ascertain the gene contribution to disease.
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Affiliation(s)
- Qi Li
- Department of Pediatrics, Nephrology Section, Yale School of Medicine, New Haven, Connecticut, USA
| | - Ashima Gulati
- Department of Internal Medicine, Nephrology Section, Yale School of Medicine, New Haven, Connecticut, USA
| | - Mathieu Lemaire
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Timothy Nottoli
- Yale Gene Editing Center, Yale School of Medicine, New Haven, Connecticut, USA
| | - Allen Bale
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Alda Tufro
- Department of Pediatrics, Nephrology Section, Yale School of Medicine, New Haven, Connecticut, USA; Department of Cell and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut, USA.
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Onodera R, Nihei S, Kimura T, Tomita T, Kudo K. Severe proteinuria during the administration of bevacizumab plus mFOLFOX6 in a colorectal cancer patient after kidney transplantation: a case report. J Pharm Health Care Sci 2020. [DOI: 10.1186/s40780-020-00175-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Bevacizumab (BEV) leads to proteinuria and renal damage. It is not clear whether the administration of immunosuppressive drugs after renal transplantation affects the safety of BEV administration. We report a case of severe proteinuria caused by BEV plus 5-fluorouracil, levofolinate, and oxaliplatin (mFOLFOX6) in a patient who had previously undergone kidney transplantation and the administration of tacrolimus.
Case presentation
The patient was a 67-year-old man with a history of diabetes and hypertension. He developed chronic renal failure 14 years earlier and underwent right kidney transplantation from a living donor followed by the administration of tacrolimus and mycophenolate mofetil for immunosuppression. After kidney transplantation, the patient was diagnosed with colorectal cancer with multiple lung and liver metastases and received BEV plus mFOLFOX6. After 5 cycles, proteinuria was observed, with a urinary protein concentration of > 300 mg/dL (urine protein creatinine ratio: 3.5), and after 16 cycles, the urinary protein concentration was > 1000 mg/dL (urine protein creatinine ratio: 7.1). Subsequently, BEV was discontinued, and only mFOLFOX6 administration was continued. Tacrolimus continued to be administered during chemotherapy. There was no association between serum tacrolimus concentration and proteinuria.
Conclusions
In this case, BEV administration caused severe proteinuria without affecting blood levels of tacrolimus. Patients with risk factors for renal impairment should be carefully evaluated for the risks and benefits of BEV administration.
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9
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Nephrotic syndrome in a dish: recent developments in modeling in vitro. Pediatr Nephrol 2020; 35:1363-1372. [PMID: 30820702 PMCID: PMC7316697 DOI: 10.1007/s00467-019-4203-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 12/20/2018] [Accepted: 01/16/2019] [Indexed: 01/05/2023]
Abstract
Nephrotic syndrome is a heterogeneous disease, and one of the most frequent glomerular disorders among children. Depending on the etiology, it may result in end-stage renal disease and the need for renal replacement therapy. A dysfunctional glomerular filtration barrier, comprising of endothelial cells, the glomerular basement membrane and podocytes, characterizes nephrotic syndrome. Podocytes are often the primary target cells in the pathogenesis, in which not only the podocyte function but also their crosstalk with other glomerular cell types can be disturbed due to a myriad of factors. The pathophysiology of nephrotic syndrome is highly complex and studying molecular mechanisms in vitro requires state-of-the-art cell-based models resembling the in vivo situation and preferably a fully functional glomerular filtration barrier. Current advances in stem cell biology and microfluidic platforms have heralded a new era of three-dimensional (3D) cultures that might have the potential to recapitulate the glomerular filtration barrier in vitro. Here, we highlight the molecular basis of nephrotic syndrome and discuss requirements to accurately study nephrotic syndrome in vitro, including an overview of specific podocyte markers, cutting-edge stem cell organoids, and the implementation of microfluidic platforms. The development of (patho) physiologically relevant glomerular models will accelerate the identification of molecular targets involved in nephrotic syndrome and may be the harbinger of a new era of therapeutic avenues.
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10
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Inoue K, Gan G, Ciarleglio M, Zhang Y, Tian X, Pedigo CE, Cavanaugh C, Tate J, Wang Y, Cross E, Groener M, Chai N, Wang Z, Justice A, Zhang Z, Parikh CR, Wilson FP, Ishibe S. Podocyte histone deacetylase activity regulates murine and human glomerular diseases. J Clin Invest 2019; 129:1295-1313. [PMID: 30776024 DOI: 10.1172/jci124030] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 01/10/2019] [Indexed: 12/21/2022] Open
Abstract
We identified 2 genes, histone deacetylase 1 (HDAC1) and HDAC2, contributing to the pathogenesis of proteinuric kidney diseases, the leading cause of end-stage kidney disease. mRNA expression profiling from proteinuric mouse glomeruli was linked to Connectivity Map databases, identifying HDAC1 and HDAC2 with the differentially expressed gene set reversible by HDAC inhibitors. In numerous progressive glomerular disease models, treatment with valproic acid (a class I HDAC inhibitor) or SAHA (a pan-HDAC inhibitor) mitigated the degree of proteinuria and glomerulosclerosis, leading to a striking increase in survival. Podocyte HDAC1 and HDAC2 activities were increased in mice podocytopathy models, and podocyte-associated Hdac1 and Hdac2 genetic ablation improved proteinuria and glomerulosclerosis. Podocyte early growth response 1 (EGR1) was increased in proteinuric patients and mice in an HDAC1- and HDAC2-dependent manner. Loss of EGR1 in mice reduced proteinuria and glomerulosclerosis. Longitudinal analysis of the multicenter Veterans Aging Cohort Study demonstrated a 30% reduction in mean annual loss of estimated glomerular filtration rate, and this effect was more pronounced in proteinuric patients receiving valproic acid. These results strongly suggest that inhibition of HDAC1 and HDAC2 activities may suppress the progression of human proteinuric kidney diseases through the regulation of EGR1.
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Affiliation(s)
| | - Geliang Gan
- Yale School of Public Health, Department of Biostatistics, Yale Center for Analytical Sciences, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Maria Ciarleglio
- Yale School of Public Health, Department of Biostatistics, Yale Center for Analytical Sciences, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Yan Zhang
- State Key Laboratory of Organ Failure Research, Nanfang Hospital.,Department of Cardiology, Nanfang Hospital, and.,Center for Bioinformatics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | | | | | - Corey Cavanaugh
- Department of Internal Medicine, and.,Program of Applied Translational Research, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Janet Tate
- VA Connecticut Healthcare System, West Haven, Connecticut, USA
| | - Ying Wang
- Department of Internal Medicine, and
| | | | | | | | - Zhen Wang
- Department of Internal Medicine, and
| | - Amy Justice
- Department of Internal Medicine, and.,VA Connecticut Healthcare System, West Haven, Connecticut, USA
| | - Zhenhai Zhang
- State Key Laboratory of Organ Failure Research, Nanfang Hospital.,Department of Cardiology, Nanfang Hospital, and.,Center for Bioinformatics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Chirag R Parikh
- Department of Internal Medicine, Division of Nephrology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Francis P Wilson
- Department of Internal Medicine, and.,Program of Applied Translational Research, Yale University School of Medicine, New Haven, Connecticut, USA
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Bates DO, Beazley-Long N, Benest AV, Ye X, Ved N, Hulse RP, Barratt S, Machado MJ, Donaldson LF, Harper SJ, Peiris-Pages M, Tortonese DJ, Oltean S, Foster RR. Physiological Role of Vascular Endothelial Growth Factors as Homeostatic Regulators. Compr Physiol 2018; 8:955-979. [PMID: 29978898 DOI: 10.1002/cphy.c170015] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The vascular endothelial growth factor (VEGF) family of proteins are key regulators of physiological systems. Originally linked with endothelial function, they have since become understood to be principal regulators of multiple tissues, both through their actions on vascular cells, but also through direct actions on other tissue types, including epithelial cells, neurons, and the immune system. The complexity of the five members of the gene family in terms of their different splice isoforms, differential translation, and specific localizations have enabled tissues to use these potent signaling molecules to control how they function to maintain their environment. This homeostatic function of VEGFs has been less intensely studied than their involvement in disease processes, development, and reproduction, but they still play a substantial and significant role in healthy control of blood volume and pressure, interstitial volume and drainage, renal and lung function, immunity, and signal processing in the peripheral and central nervous system. The widespread expression of VEGFs in healthy adult tissues, and the disturbances seen when VEGF signaling is inhibited support this view of the proteins as endogenous regulators of normal physiological function. This review summarizes the evidence and recent breakthroughs in understanding of the physiology that is regulated by VEGF, with emphasis on the role they play in maintaining homeostasis. © 2017 American Physiological Society. Compr Physiol 8:955-979, 2018.
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Affiliation(s)
- David O Bates
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | | | - Andrew V Benest
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Xi Ye
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Nikita Ved
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Richard P Hulse
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Shaney Barratt
- Academic Respiratory Unit, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - Maria J Machado
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Lucy F Donaldson
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Steven J Harper
- School of Physiology, Pharmacology & Neuroscience, Medical School, University of Bristol, Bristol, United Kingdom
| | - Maria Peiris-Pages
- Cancer Research UK Manchester Institute, The University of Manchester, Manchester, United Kingdom
| | - Domingo J Tortonese
- Centre for Comparative and Clinical Anatomy, University of Bristol, Bristol, United Kingdom
| | - Sebastian Oltean
- Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, United Kingdom
| | - Rebecca R Foster
- Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
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12
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Modulation of VEGF-A Alternative Splicing as a Novel Treatment in Chronic Kidney Disease. Genes (Basel) 2018; 9:genes9020098. [PMID: 29462869 PMCID: PMC5852594 DOI: 10.3390/genes9020098] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 02/08/2018] [Accepted: 02/09/2018] [Indexed: 01/05/2023] Open
Abstract
Vascular endothelial growth factor A (VEGF-A) is a prominent pro-angiogenic and pro-permeability factor in the kidney. Alternative splicing of the terminal exon of VEGF-A through the use of an alternative 3' splice site gives rise to a functionally different family of isoforms, termed VEGF-Axxxb, known to have anti-angiogenic and anti-permeability properties. Dysregulation of the VEGF-Axxx/VEGF-Axxxb isoform balance has recently been reported in several kidney pathologies, including diabetic nephropathy (DN) and Denys-Drash syndrome. Using mouse models of kidney disease where the VEGF-A isoform balance is disrupted, several reports have shown that VEGF-A165b treatment/over-expression in the kidney is therapeutically beneficial. Furthermore, inhibition of certain splice factor kinases involved in the regulation of VEGF-A terminal exon splicing has provided some mechanistic insight into how VEGF-A splicing could be regulated in the kidney. This review highlights the importance of further investigation into the novel area of VEGF-A splicing in chronic kidney disease pathogenesis and how future studies may allow for the development of splicing-modifying therapeutic drugs.
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13
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Stevens M, Neal CR, Salmon AHJ, Bates DO, Harper SJ, Oltean S. Vascular Endothelial Growth Factor-A165b Restores Normal Glomerular Water Permeability in a Diphtheria-Toxin Mouse Model of Glomerular Injury. Nephron Clin Pract 2018; 139:51-62. [PMID: 29393270 DOI: 10.1159/000485664] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 11/24/2017] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND/AIMS Genetic cell ablation using the human diphtheria toxin receptor (hDTR) is a new strategy used for analysing cellular function. Diphtheria toxin (DT) is a cytotoxic protein that leaves mouse cells relatively unaffected, but upon binding to hDTR it ultimately leads to cell death. We used a podocyte-specific hDTR expressing (Pod-DTR) mouse to assess the anti-permeability and cyto-protective effects of the splice isoform vascular endothelial growth factor (VEGF-A165b). METHODS The Pod-DTR mouse was crossed with a mouse that over-expressed VEGF-A165b specifically in the podocytes (Neph-VEGF-A165b). Wild type (WT), Pod-DTR, Neph-VEGF-A165b and Pod-DTR X Neph-VEGF-A165b mice were treated with several doses of DT (1, 5, 100, and 1,000 ng/g bodyweight). Urine was collected and the glomerular water permeability (LpA/Vi) was measured ex vivo after 14 days. Structural analysis and podocyte marker expression were also assessed. RESULTS Pod-DTR mice developed an increased glomerular LpA/Vi 14 days after administration of DT (all doses), which was prevented when the mice over-expressed VEGF-A165b. No major structural abnormalities, podocyte ablation or albuminuria was observed in Pod-DTR mice, indicating this to be a mild model of podocyte disease. However, a change in expression and localisation of nephrin within the podocytes was observed, indicating disruption of the slit diaphragm in the Pod-DTR mice. This was prevented in the Pod-DTR X Neph-VEGF-A165b mice. CONCLUSION Although only a mild model of podocyte injury, over-expression of the anti-permeability VEGF-A165b isoform in the podocytes of Pod-DTR mice had a protective effect. Therefore, this study further highlights the therapeutic potential of VEGF-A165b in glomerular disease.
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Affiliation(s)
- Megan Stevens
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, United Kingdom.,School of Physiology, Pharmacology and Neurosciences, Bristol, United Kingdom.,Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - Christopher R Neal
- School of Physiology, Pharmacology and Neurosciences, Bristol, United Kingdom.,Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - Andrew H J Salmon
- School of Physiology, Pharmacology and Neurosciences, Bristol, United Kingdom.,Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - David O Bates
- Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Steven J Harper
- School of Physiology, Pharmacology and Neurosciences, Bristol, United Kingdom.,Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - Sebastian Oltean
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, United Kingdom.,School of Physiology, Pharmacology and Neurosciences, Bristol, United Kingdom.,Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
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15
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Suyama M, Miyazaki Y, Matsusaka T, Sugano N, Ueda H, Kawamura T, Ogura M, Yokoo T. Forced expression of vascular endothelial growth factor-A in podocytes decreases mesangial cell numbers and attenuates endothelial cell differentiation in the mouse glomerulus. Clin Exp Nephrol 2017; 22:266-274. [DOI: 10.1007/s10157-017-1450-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 07/18/2017] [Indexed: 11/30/2022]
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Turner RJ, Eikmans M, Bajema IM, Bruijn JA, Baelde HJ. Stability and Species Specificity of Renal VEGF-A Splicing Patterns in Kidney Disease. PLoS One 2016; 11:e0162166. [PMID: 27598902 PMCID: PMC5012578 DOI: 10.1371/journal.pone.0162166] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 07/08/2016] [Indexed: 12/29/2022] Open
Abstract
Vascular endothelial growth factor A (VEGF-A) is essential for maintaining the glomerular filtration barrier. Absolute renal levels of VEGF-A change in patients with diabetic nephropathy and inflammatory kidney diseases, but whether changes in the renal splicing patterns of VEGF-A play a role remains unclear. In this study, we investigated mRNA splicing patterns of pro-angiogenic isoforms of VEGF-A in glomeruli and whole kidney samples from human patients with kidney disease and from mouse models of kidney disease. Kidney biopsies were obtained from patients with acute rejection following kidney transplantation, patients with diabetic nephropathy, and control subjects. In addition, kidney samples were obtained from mice with lupus nephritis, mice with diabetes mellitus, and control mice. The relative expression of each VEGF-A splice variant was measured using RT-PCR followed by quantitative fragment analysis. The pattern of renal VEGF-A splice variants was unchanged in diabetic nephropathy and lupus nephritis and was stable throughout disease progression in acute transplant rejection and diabetic nephropathy; these results suggest renal VEGF-A splicing stability during kidney disease. The splicing patterns were species-specific; in the control human kidney samples, VEGF-A 121 was the dominant isoform, whereas VEGF-A 164 was the dominant isoform measured in the mouse kidney samples.
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Affiliation(s)
- R. J. Turner
- Department of Pathology, Leiden University Medical Center, Leiden, the Netherlands
- * E-mail:
| | - M. Eikmans
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, the Netherlands
| | - I. M. Bajema
- Department of Pathology, Leiden University Medical Center, Leiden, the Netherlands
| | - J. A. Bruijn
- Department of Pathology, Leiden University Medical Center, Leiden, the Netherlands
| | - H. J. Baelde
- Department of Pathology, Leiden University Medical Center, Leiden, the Netherlands
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17
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Logue OC, McGowan JWD, George EM, Bidwell GL. Therapeutic angiogenesis by vascular endothelial growth factor supplementation for treatment of renal disease. Curr Opin Nephrol Hypertens 2016; 25:404-9. [PMID: 27367910 PMCID: PMC4974125 DOI: 10.1097/mnh.0000000000000256] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
PURPOSE OF REVIEW Vascular endothelial growth factors (VEGFs) influence renal function through angiogenesis, with VEGF-A being the most potent inducer of vascular formation. In the normal glomerulus, tight homeostatic balance is maintained between the levels of VEGF-A isoforms produced by podocyte cells, and the VEGF receptors (VEGFRs) expressed by glomerular endothelial, mesangial, and podocyte cells. Renal disease occurs when this homeostatic balance is lost, manifesting in the abnormal autocrine and paracrine VEGF-A/VEGFR signaling, ultrastructural glomerular and tubular damage, and impaired filtration. RECENT FINDINGS Preclinical disease models of ischemic renal injury, including acute ischemia/reperfusion, thrombotic microangiopathy, and chronic renovascular disease, treated with exogenous VEGF supplementation demonstrated therapeutic efficacy. These results suggest a therapeutic VEGF-A paracrine effect on endothelial cells in the context of acute or chronic obstructive ischemia. Conversely, renal dysfunction in diabetic nephropathy appears to occur through an upregulated VEGF autocrine effect on podocyte cells, which is exacerbated by hyperglycemia. Therefore, VEGF supplementation therapy may be contraindicated for treatment of diabetic nephropathy, but specific results will depend on dose and on the specific site of VEGF delivery. A drug delivery system that demonstrates cell specificity for glomerular or peritubular capillaries could be employed to restore balance to VEGF-A/VEGFR2 signaling, and by doing so, prevent the progression to end-stage renal disease. SUMMARY The review discusses the preclinical data available for VEGF supplementation therapy in models of renal disease.
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Affiliation(s)
- Omar C. Logue
- Department of Neurology, University of Mississippi Medical Center, Jackson, MS
| | | | - Eric M. George
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS
- Department of Biochemistry, University of Mississippi Medical Center, Jackson, MS
| | - Gene L. Bidwell
- Department of Neurology, University of Mississippi Medical Center, Jackson, MS
- Department of Biochemistry, University of Mississippi Medical Center, Jackson, MS
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18
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Azizoglu DB, Cleaver O. Blood vessel crosstalk during organogenesis-focus on pancreas and endothelial cells. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2016; 5:598-617. [PMID: 27328421 DOI: 10.1002/wdev.240] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 03/23/2016] [Accepted: 04/16/2016] [Indexed: 01/02/2023]
Abstract
Blood vessels form a highly branched, interconnected, and largely stereotyped network of tubes that sustains every organ and tissue in vertebrates. How vessels come to take on their particular architecture, or how they are 'patterned,' and in turn, how they influence surrounding tissues are fundamental questions of organogenesis. Decades of work have begun to elucidate how endothelial progenitors arise and home to precise locations within tissues, integrating attractive and repulsive cues to build vessels where they are needed. Conversely, more recent findings have revealed an exciting facet of blood vessel interaction with tissues, where vascular cells provide signals to developing organs and progenitors therein. Here, we discuss the exchange of reciprocal signals between endothelial cells and neighboring tissues during embryogenesis, with a special focus on the developing pancreas. Understanding the mechanisms driving both sides of these interactions will be crucial to the development of therapies, from improving organ regeneration to efficient production of cell based therapies. Specifically, elucidating the interface of the vasculature with pancreatic lineages, including endocrine cells, will instruct approaches such as generation of replacement beta cells for Type I diabetes. WIREs Dev Biol 2016, 5:598-617. doi: 10.1002/wdev.240 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- D Berfin Azizoglu
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ondine Cleaver
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
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19
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Wang H, Yue Z, Wu J, Liu T, Mo Y, Jiang X, Sun L. The Accumulation of VEGFA in the Glomerular Basement Membrane and Its Relationship with Podocyte Injury and Proteinuria in Alport Syndrome. PLoS One 2015; 10:e0135648. [PMID: 26274923 PMCID: PMC4537134 DOI: 10.1371/journal.pone.0135648] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 07/23/2015] [Indexed: 11/23/2022] Open
Abstract
The pathogenesis of proteinuria in Alport syndrome (AS) remains unclear. Vascular endothelial growth factor A (VEGFA) is a key regulator of the glomerular filtration barrier (GFB). This study explored the expression of VEGFA in the glomeruli and its accumulation in the glomerular basement membrane (GBM) and their relationship with podocyte injury and proteinuria in Alport syndrome (AS). Clinical data and renal tissues of control patients (11 cases) and AS patients (25 cases) were included. AS patients were further divided into 2 groups according to the quantities of their urinary protein: mild to moderate proteinuria group (proteinuria <50 mg/kg/d, 15 cases) and heavy proteinuria group (proteinuria ≥50 mg/kg/d, 10 cases). The expression and distribution of VEGFA and VEGF receptor 2 (VEGFR2) in the GFB, the phosphorylation of VEGFR2 (p-VEGFR2) and nephrin (p-nephrin), and the expression of synaptopodin and nephrin in the glomeruli were detected by immune electron microscopy and/or immunofluorescence, and their relationships to proteinuria in AS patients were analyzed. The accumulation of VEGFA in the GBM was increased in AS patients. The expression of VEGFA and the levels of p-VEGFR2 and p-nephrin in glomeruli were increased and were positively correlated with the degree of proteinuria in AS patients. The expression of synaptopodin and nephrin were decreased and were negatively correlated with the degree of proteinuria in AS patients. The over expressed VEGFA in the glomeruli and its accumulation in the GBM may activate the VEGFA-VEGFR2 and nephrin signaling pathways and lead to podocyte injury and occurrence of proteinuria in AS.
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Affiliation(s)
- Haiyan Wang
- Children’s Kidney Disease Center, Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, P. R. China
- Department of Pediatrics, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Zhihui Yue
- Children’s Kidney Disease Center, Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Jinlang Wu
- Department of Electron Microscopy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, P. R. China
| | - Ting Liu
- Children’s Kidney Disease Center, Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Ying Mo
- Children’s Kidney Disease Center, Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Xiaoyun Jiang
- Children’s Kidney Disease Center, Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Liangzhong Sun
- Children’s Kidney Disease Center, Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, P. R. China
- * E-mail:
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Abstract
The function of the kidney, filtering blood and concentrating metabolic waste into urine, takes place in an intricate and functionally elegant structure called the renal glomerulus. Normal glomerular function retains circulating cells and valuable macromolecular components of plasma in blood, resulting in urine with just trace amounts of proteins. Endothelial cells of glomerular capillaries, the podocytes wrapped around them, and the fused extracellular matrix these cells form altogether comprise the glomerular filtration barrier, a dynamic and highly selective filter that sieves on the basis of molecular size and electrical charge. Current understanding of the structural organization and the cellular and molecular basis of renal filtration draws from studies of human glomerular diseases and animal models of glomerular dysfunction.
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Affiliation(s)
- Rizaldy P Scott
- Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Susan E Quaggin
- Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
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21
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Albert GI, Schell C, Kirschner KM, Schäfer S, Naumann R, Müller A, Kretz O, Kuropka B, Girbig M, Hübner N, Krause E, Scholz H, Huber TB, Knobeloch KP, Freund C. The GYF domain protein CD2BP2 is critical for embryogenesis and podocyte function. J Mol Cell Biol 2015; 7:402-14. [PMID: 26082520 DOI: 10.1093/jmcb/mjv039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 04/15/2015] [Indexed: 01/11/2023] Open
Abstract
Scaffolding proteins play pivotal roles in the assembly of macromolecular machines such as the spliceosome. The adaptor protein CD2BP2, originally identified as a binding partner of the adhesion molecule CD2, is a pre-spliceosomal assembly factor that utilizes its glycine-tyrosine-phenylalanine (GYF) domain to co-localize with spliceosomal proteins. So far, its function in vertebrates is unknown. Using conditional gene targeting in mice, we show that CD2BP2 is crucial for embryogenesis, leading to growth retardation, defects in vascularization, and premature death at embryonic day 10.5 when absent. Ablation of the protein in bone marrow-derived macrophages indicates that CD2BP2 is involved in the alternative splicing of mRNA transcripts from diverse origins. At the molecular level, we identified the phosphatase PP1 to be recruited to the spliceosome via the N-terminus of CD2BP2. Given the strong expression of CD2BP2 in podocytes of the kidney, we use selective depletion of CD2BP2, in combination with next-generation sequencing, to monitor changes in exon usage of genes critical for podocyte functions, including VEGF and actin regulators. CD2BP2-depleted podocytes display foot process effacement, and cause proteinuria and ultimately lethal kidney failure in mice. Collectively, our study defines CD2BP2 as a non-redundant splicing factor essential for embryonic development and podocyte integrity.
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Affiliation(s)
- Gesa I Albert
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany Leibniz-Institut fuer Molekulare Pharmakologie, 13125 Berlin, Germany
| | - Christoph Schell
- Renal Division, University Hospital Freiburg, 79106 Freiburg, Germany Speman Graduate School for Medicine and Biology, University of Freiburg, 79106 Freiburg, Germany Faculty of Biology, University Freiburg, 79106 Freiburg, Germany
| | - Karin M Kirschner
- Institute fuer Vegetative Physiologie, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Sebastian Schäfer
- Experimental Genetics and Cardiovascular Diseases, MDC, 13125 Berlin, Germany
| | - Ronald Naumann
- Transgenic Core Facility, Max-Planck-Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Alexandra Müller
- Institute of Neuropathology, University of Freiburg, 79106 Freiburg, Germany
| | - Oliver Kretz
- Renal Division, University Hospital Freiburg, 79106 Freiburg, Germany Institute of Cell Biology & Anatomy, University of Freiburg, 79106 Freiburg, Germany
| | - Benno Kuropka
- Leibniz-Institut fuer Molekulare Pharmakologie, 13125 Berlin, Germany
| | - Mathias Girbig
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
| | - Norbert Hübner
- Experimental Genetics and Cardiovascular Diseases, MDC, 13125 Berlin, Germany
| | - Eberhard Krause
- Leibniz-Institut fuer Molekulare Pharmakologie, 13125 Berlin, Germany
| | - Holger Scholz
- Institute fuer Vegetative Physiologie, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Tobias B Huber
- Renal Division, University Hospital Freiburg, 79106 Freiburg, Germany Speman Graduate School for Medicine and Biology, University of Freiburg, 79106 Freiburg, Germany BIOSS Centre for Biological Signaling Studies, Albert-Ludwigs-University, 79106 Freiburg, Germany
| | | | - Christian Freund
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany Leibniz-Institut fuer Molekulare Pharmakologie, 13125 Berlin, Germany
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22
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Magyar Z, Schönleber J, Romics M, Hruby E, Nagy B, Sulya B, Beke A, Harmath Á, Jeager J, Rigó J, Görbe É. Expression of VEGF in neonatal urinary obstruction: does expression of VEGF predict hydronephrosis? Med Sci Monit 2015; 21:1319-23. [PMID: 25951999 PMCID: PMC4436944 DOI: 10.12659/msm.894133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND In animal studies, the inhibition of VEGF activity results in high mortality and impaired renal and glomerular development. Mechanical stimuli, like mechanical stretch in respiratory and circulatory systems, results in an elevated expression of VEGF. In animal models, the experimental urinary obstruction is associated with stretching of tubular cells and activations of the renin-angiotensin system. This results in the upregulation of vascular endothelial growth factor (VEGF) and TNF-alfa. MATERIAL/METHODS Tissue samples from urinary tract obstruction were collected and immunohistochemistry was performed in 14 patients (average age: 7.1±4.1 years). The control histology group consisted of ureteropelvic junction tissue from 10 fetuses after midtrimester artificial abortion. The fetuses did not have any failure at ultrasound screening and pathological examination. The mean gestational age was 20.6 weeks of gestation (±2.2SD). Expression of VEGF was detected with immunohistochemistry method. RESULTS Expression of VEGF was found in varying intensity in the submucosa and subserosa layers, but only in the test tissue (placental tissue). The tissue of the patients with urinary obstruction and the tissue of the fetal ureteropelvic junction without urinary obstruction were negative for expression of VEGF. The repeated examination showed negative cells and no color staining. CONCLUSIONS The pressure due to congenital urogenital obstruction resulting in mechanical stress in cells did not increase the expression of VEGF in young children in our study. To find a correlation between urogenital tract obstruction and increased expression of VEGF, we need to perform more examinations because the connection may be of therapeutic significance.
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Affiliation(s)
- Zsófia Magyar
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
| | | | - Miklós Romics
- Department of Urology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
| | - Ervin Hruby
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
| | - Bálint Nagy
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
| | - Bálint Sulya
- Department of Urology, Heim Pál Childrens Hospital, Budapest, Hungary
| | - Artúr Beke
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
| | - Ágnes Harmath
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
| | - Judit Jeager
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
| | - János Rigó
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
| | - Éva Görbe
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Faculty of Medicine, Budapest, Hungary
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Chen H, Wang D, Xia R, Mao Q, Xia H. A novel adenoviral vector carrying an all-in-one Tet-On system with an autoregulatory loop for tight, inducible transgene expression. BMC Biotechnol 2015; 15:4. [PMID: 25888000 PMCID: PMC4331377 DOI: 10.1186/s12896-015-0121-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Accepted: 01/30/2015] [Indexed: 01/24/2023] Open
Abstract
Background One of the most commonly used vectors for gene therapy is the adenoviral vector; its ability to tightly regulate transgene expression is critical for optimizing therapeutic outcomes. The tetracycline-regulated system (especially the Tet-On system) for gene expression is one of the most valuable tools for controlling gene expression. The major problem of an adenoviral vector carrying a Tet-On system is suboptimal regulation of transgene expression. Results We constructed a single adenoviral vector carrying in its E1 region a novel “all-in-one” Tet-On system with an autoregulatory loop. This system had improved Dox-inducible gene expression in terms of low basal expression, high induced expression and high responsiveness to Dox. To our knowledge, this is the first reported adenovirus-based, all-in-one Tet-On system with an autoregulatory loop inserted into a single region of adenoviral genome. This system was further tested by inducible expression of soluble tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL). The adenovirus that expressed soluble TRAIL under the control of this novel Tet-On system showed tumor-derived cells inhibitory activity in SW480 cells only under induced conditions. Conclusions Our novel, single adenoviral vector carrying in its E1 region an all-in-one Tet-On system with an autoregulatory loop displayed tight regulation of transgene expression in vitro. This system has great potential for a variety of applications, including gene therapy and the study of gene function.
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Affiliation(s)
- Hao Chen
- Laboratory of Gene Therapy, Department of Biochemistry, College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, Shaanxi, PR China.
| | - Dongyang Wang
- Laboratory of Gene Therapy, Department of Biochemistry, College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, Shaanxi, PR China.
| | - Ruiting Xia
- College of Liberal Arts and Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| | - Qinwen Mao
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA.
| | - Haibin Xia
- Laboratory of Gene Therapy, Department of Biochemistry, College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, Shaanxi, PR China.
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Fu J, Lee K, Chuang PY, Liu Z, He JC. Glomerular endothelial cell injury and cross talk in diabetic kidney disease. Am J Physiol Renal Physiol 2014; 308:F287-97. [PMID: 25411387 DOI: 10.1152/ajprenal.00533.2014] [Citation(s) in RCA: 183] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Diabetic kidney disease (DKD) remains a leading cause of new-onset end-stage renal disease (ESRD), and yet, at present, the treatment is still very limited. A better understanding of the pathogenesis of DKD is therefore necessary to develop more effective therapies. Increasing evidence suggests that glomerular endothelial cell (GEC) injury plays a major role in the development and progression of DKD. Alteration of the glomerular endothelial cell surface layer, including its major component, glycocalyx, is a leading cause of microalbuminuria observed in early DKD. Many studies suggest a presence of cross talk between glomerular cells, such as between GEC and mesangial cells or GEC and podocytes. PDGFB/PDGFRβ is a major mediator for GEC and mesangial cell cross talk, while vascular endothelial growth factor (VEGF), angiopoietins, and endothelin-1 are the major mediators for GEC and podocyte communication. In DKD, GEC injury may lead to podocyte damage, while podocyte loss further exacerbates GEC injury, forming a vicious cycle. Therefore, GEC injury may predispose to albuminuria in diabetes either directly or indirectly by communication with neighboring podocytes and mesangial cells via secreted mediators. Identification of novel mediators of glomerular cell cross talk, such as microRNAs, will lead to a better understanding of the pathogenesis of DKD. Targeting these mediators may be a novel approach to develop more effective therapy for DKD.
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Affiliation(s)
- Jia Fu
- Research Institute of Nephrology, Jinling Hospital, Nanjing University School of Medicine, Jiangsu, China; and
| | - Kyung Lee
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Peter Y Chuang
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Zhihong Liu
- Research Institute of Nephrology, Jinling Hospital, Nanjing University School of Medicine, Jiangsu, China; and
| | - John Cijiang He
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, New York
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Abstract
PURPOSE OF REVIEW The vascular endothelial growth factor (VEGF) system is a multifarious network and an exemplar of an intraglomerular signalling pathway. Here, we review recent advances that highlight the subtle nature of the renal VEGF system and its influencers. RECENT FINDINGS The VEGF system is no longer considered as a simple paracrine, ligand-receptor interaction under the regulatory control of a soluble 'decoy', soluble fms-like tyrosine kinase-1 (sFLT1). Rather, the abundantly expressed, podocyte-derived VEGF isoform, VEGF-A, is now recognized to mediate both paracrine effects across the filtration barrier and autocrine actions, functioning to preserve the integrity of the cells from which it arises. Autocrine actions of the podocyte VEGF system extend beyond those of the VEGF-A isoform, however, with sFLT1 itself now appreciated as regulating podocyte morphology by binding to lipid microdomains. These and other functions of the VEGF system are profoundly affected by the presence, nature and abundance of influencers both intrinsic and extrinsic to the pathway, the latter most readily exemplified by the role of the cytokine in the diabetic kidney. SUMMARY The glomerular VEGF system plays a delicate, yet critical, role in preserving renal homeostasis. It may be intricate, but 'in all things of nature there is something of the marvellous'.
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26
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Yi qi qing re gao attenuates podocyte injury and inhibits vascular endothelial growth factor overexpression in puromycin aminonucleoside rat model. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:375986. [PMID: 24963322 PMCID: PMC4055581 DOI: 10.1155/2014/375986] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/24/2014] [Accepted: 04/26/2014] [Indexed: 11/18/2022]
Abstract
Proteinuria is the hallmark of chronic kidney disease. Podocyte damage underlies the formation of proteinuria, and vascular endothelial growth factor (VEGF) functions as an autocrine/paracrine regulator. Yi Qi Qing Re Gao (YQQRG) has been used to treat proteinuria for more than two decades. The objective of this study was to investigate the protective effect and possible mechanisms of YQQRG on puromycin aminonucleoside (PAN) rat model. Eighty male Sprague-Dawley rats were randomized into sham group, PAN group, PAN + YQQRG group, and PAN + fosinopril group. Treatments were started 7 days before induction of nephrosis (a single intravenous injection of 40 mg/kg PAN) until day 15. 24 h urinary samples were collected on days 5, 9, and 14. The animals were sacrificed on days 3, 10, and 15, respectively. Blood samples and renal tissues were obtained for detection of biochemical and molecular biological parameters. YQQRG significantly reduced proteinuria, elevated serum albumin, and alleviated renal pathological lesions. YQQRG inhibited VEGF-A, nephrin, podocin, and CD2AP mRNA expression and elevated nephrin, podocin, and CD2AP protein levels starting on day 3. In conclusion, YQQRG attenuates podocyte injury in the rat PAN model through downregulation of VEGF-A and restoration of nephrin, podocin, and CD2AP protein expression.
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Badal SS, Danesh FR. New insights into molecular mechanisms of diabetic kidney disease. Am J Kidney Dis 2014; 63:S63-83. [PMID: 24461730 DOI: 10.1053/j.ajkd.2013.10.047] [Citation(s) in RCA: 139] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 10/08/2013] [Indexed: 01/12/2023]
Abstract
Diabetic kidney disease remains a major microvascular complication of diabetes and the most common cause of chronic kidney failure requiring dialysis in the United States. Medical advances over the past century have substantially improved the management of diabetes mellitus and thereby have increased patient survival. However, current standards of care reduce but do not eliminate the risk of diabetic kidney disease, and further studies are warranted to define new strategies for reducing the risk of diabetic kidney disease. In this review, we highlight some of the novel and established molecular mechanisms that contribute to the development of the disease and its outcomes. In particular, we discuss recent advances in our understanding of the molecular mechanisms implicated in the pathogenesis and progression of diabetic kidney disease, with special emphasis on the mitochondrial oxidative stress and microRNA targets. Additionally, candidate genes associated with susceptibility to diabetic kidney disease and alterations in various cytokines, chemokines, and growth factors are addressed briefly.
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Affiliation(s)
- Shawn S Badal
- Interdepartmental Graduate Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX
| | - Farhad R Danesh
- Interdepartmental Graduate Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX; Section of Nephrology, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX.
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Veron D, Aggarwal PK, Velazquez H, Kashgarian M, Moeckel G, Tufro A. Podocyte-specific VEGF-a gain of function induces nodular glomerulosclerosis in eNOS null mice. J Am Soc Nephrol 2014; 25:1814-24. [PMID: 24578128 DOI: 10.1681/asn.2013070752] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
VEGF-A and nitric oxide are essential for glomerular filtration barrier homeostasis and are dysregulated in diabetic nephropathy. Here, we examined the effect of excess podocyte VEGF-A on the renal phenotype of endothelial nitric oxide synthase (eNOS) knockout mice. Podocyte-specific VEGF(164) gain of function in eNOS(-/-) mice resulted in nodular glomerulosclerosis, mesangiolysis, microaneurysms, and arteriolar hyalinosis associated with massive proteinuria and renal failure in the absence of diabetic milieu or hypertension. In contrast, podocyte-specific VEGF(164) gain of function in wild-type mice resulted in less pronounced albuminuria and increased creatinine clearance. Transmission electron microscopy revealed glomerular basement membrane thickening and podocyte effacement in eNOS(-/-) mice with podocyte-specific VEGF(164) gain of function. Furthermore, glomerular nodules overexpressed collagen IV and laminin extensively. Biotin-switch and proximity ligation assays demonstrated that podocyte-specific VEGF(164) gain of function decreased glomerular S-nitrosylation of laminin in eNOS(-/-) mice. In addition, treatment with VEGF-A decreased S-nitrosylated laminin in cultured podocytes. Collectively, these data indicate that excess glomerular VEGF-A and eNOS deficiency is necessary and sufficient to induce Kimmelstiel-Wilson-like nodular glomerulosclerosis in mice through a process that involves deposition of laminin and collagen IV and de-nitrosylation of laminin.
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Affiliation(s)
| | | | | | - Michael Kashgarian
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut
| | - Gilbert Moeckel
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut
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Reiser J, Sever S, Faul C. Signal transduction in podocytes--spotlight on receptor tyrosine kinases. Nat Rev Nephrol 2014; 10:104-15. [PMID: 24394191 PMCID: PMC4109315 DOI: 10.1038/nrneph.2013.274] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The mammalian kidney filtration barrier is a complex multicellular, multicomponent structure that maintains homeostasis by regulating electrolytes, acid-base balance, and blood pressure (via maintenance of salt and water balance). To perform these multiple functions, podocytes--an important component of the filtration apparatus--must process a series of intercellular signals. Integrating these signals with diverse cellular responses enables a coordinated response to various conditions. Although mature podocytes are terminally differentiated and cannot proliferate, they are able to respond to growth factors. It is possible that the initial response of podocytes to growth factors is beneficial and protective, and might include the induction of hypertrophic cell growth. However, extended and/or uncontrolled growth factor signalling might be maladaptive and could result in the induction of apoptosis and podocyte loss. Growth factors signal via the activation of receptor tyrosine kinases (RTKs) on their target cells and around a quarter of the 58 RTK family members that are encoded in the human genome have been identified in podocytes. Pharmacological inhibitors of many RTKs exist and are currently used in experimental and clinical cancer therapy. The identification of pathological RTK-mediated signal transduction pathways in podocytes could provide a starting point for the development of novel therapies for glomerular disorders.
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Affiliation(s)
- Jochen Reiser
- Department of Medicine, Rush University Medical Center, 1735 West Harrison Street, Cohn Building, Suite 724, Chicago, IL 60612, USA
| | - Sanja Sever
- Department of Medicine, Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, 149 13th Street, Charlestown, MA 02129, USA
| | - Christian Faul
- Division of Nephrology and Hypertension, University of Miami Miller School of Medicine, 1580 North West 10th Avenue (R-762), Batchelor Building 626, Miami, FL 33136, USA
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Abstract
Vascular endothelial growth factor-A (VEGF-A) is a protein secreted by podocytes that is necessary for survival of endothelial cells, podocytes, and mesangial cells. VEGF-A regulates slit-diaphragm signaling and podocyte shape via VEGF-receptor 2-nephrin-nck-actin interactions. Chronic hyperglycemia-induced excess podocyte VEGF-A and low endothelial nitric oxide drive the development and the progression of diabetic nephropathy. The abnormal cross-talk between VEGF-A and nitric oxide pathways is fueled by the diabetic milieu, resulting in increased oxidative stress. Recent findings on these pathogenic molecular mechanisms provide new potential targets for therapy for diabetic renal disease.
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Affiliation(s)
- Alda Tufro
- Department of Pediatrics, Section of Nephrology, Yale University School of Medicine, New Haven, CT 06520-8064, USA.
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Oltean S, Neal CR, Mavrou A, Patel P, Ahad T, Alsop C, Lee T, Sison K, Qiu Y, Harper SJ, Bates DO, Salmon AHJ. VEGF165b overexpression restores normal glomerular water permeability in VEGF164-overexpressing adult mice. Am J Physiol Renal Physiol 2012; 303:F1026-36. [PMID: 22811490 DOI: 10.1152/ajprenal.00410.2011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Vascular endothelial growth factor (VEGF)-A, a family of differentially spliced proteins produced by glomerular podocytes, maintains glomerular filtration barrier function. The expression of VEGF molecules is altered in human nephropathy. We aimed to determine the roles of the angiogenic VEGF(164) isoform, and the antiangiogenic VEGF(165)b isoform in mature, adult glomeruli in vivo using conditional, inducible transgenic overexpression systems in mice. Podocyte-specific VEGF(164) overexpression (up to 100 days) was induced by oral administration of doxycycline to adult podocin-rtTA/TetO-VEGF(164) double transgenic mice. The consequences of simultaneous overexpression of VEGF(164) and VEGF(165)b were assessed in triple-transgenic podocin-rtTA/TetO-VEGF(164)/nephrin-VEGF(165)b mice. Persistent VEGF(164) overexpression did not cause proteinuria but did increase glomerular ultrafiltration coefficient between days 3 and 7. Despite persistently increased VEGF(164) levels, glomerular ultrafiltration coefficient normalized by day 14 and remained normal up to 100 days. Decreased subpodocyte space (SPS) coverage of the glomerular capillary wall accompanied increased glomerular hydraulic conductivity in VEGF(164)-overexpressing mice. The changes in glomerular ultrafiltration coefficient and SPS coverage induced by 7 days of overexpression of VEGF(164) were not present in triple transgenic VEGF(164) and VEGF(165)b overexpressing mice. These results indicate that 1) the adult mouse glomerulus is relatively resistant to induced VEGF(164) overexpression. VEGF(164) overexpression altered glomerular permeability but did not cause proteinuria in these mature, adult animals; 2) the SPS is a dynamic VEGF-responsive modulator of glomerular function; and 3) the balance of VEGF isoforms plays a critical role in the regulation of glomerular permeability. VEGF(165)b is capable of preventing VEGF(164)-induced changes in glomerular permeability and ultrastructure in vivo.
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Affiliation(s)
- Sebastian Oltean
- Microvascular Research Laboratories, School of Physiology and Pharmacology, Univ. of Bristol, Preclinical Veterinary School, Southwell St., Bristol, United Kingdom. BS2 8EJ
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Veron D, Villegas G, Aggarwal PK, Bertuccio C, Jimenez J, Velazquez H, Reidy K, Abrahamson DR, Moeckel G, Kashgarian M, Tufro A. Acute podocyte vascular endothelial growth factor (VEGF-A) knockdown disrupts alphaVbeta3 integrin signaling in the glomerulus. PLoS One 2012; 7:e40589. [PMID: 22808199 PMCID: PMC3396653 DOI: 10.1371/journal.pone.0040589] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Accepted: 06/10/2012] [Indexed: 01/13/2023] Open
Abstract
Podocyte or endothelial cell VEGF-A knockout causes thrombotic microangiopathy in adult mice. To study the mechanism involved in acute and local injury caused by low podocyte VEGF-A we developed an inducible, podocyte-specific VEGF-A knockdown mouse, and we generated an immortalized podocyte cell line (VEGFKD) that downregulates VEGF-A upon doxycycline exposure. Tet-O-siVEGF:podocin-rtTA mice express VEGF shRNA in podocytes in a doxycycline-regulated manner, decreasing VEGF-A mRNA and VEGF-A protein levels in isolated glomeruli to ∼20% of non-induced controls and urine VEGF-A to ∼30% of control values a week after doxycycline induction. Induced tet-O-siVEGF:podocin-rtTA mice developed acute renal failure and proteinuria, associated with mesangiolysis and microaneurisms. Glomerular ultrastructure revealed endothelial cell swelling, GBM lamination and podocyte effacement. VEGF knockdown decreased podocyte fibronectin and glomerular endothelial alphaVbeta3 integrin in vivo. VEGF receptor-2 (VEGFR2) interacts with beta3 integrin and neuropilin-1 in the kidney in vivo and in VEGFKD podocytes. Podocyte VEGF knockdown disrupts alphaVbeta3 integrin activation in glomeruli, detected by WOW1-Fab. VEGF silencing in cultured VEGFKD podocytes downregulates fibronectin and disrupts alphaVbeta3 integrin activation cell-autonomously. Collectively, these studies indicate that podocyte VEGF-A regulates alphaVbeta3 integrin signaling in the glomerulus, and that podocyte VEGF knockdown disrupts alphaVbeta3 integrin activity via decreased VEGFR2 signaling, thereby damaging the three layers of the glomerular filtration barrier, causing proteinuria and acute renal failure.
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Affiliation(s)
- Delma Veron
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Guillermo Villegas
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Pardeep Kumar Aggarwal
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Claudia Bertuccio
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Juan Jimenez
- Analytical Imaging Facility, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Heino Velazquez
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Kimberly Reidy
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, New York, 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
| | - Gilbert Moeckel
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Michael Kashgarian
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Alda Tufro
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, United States of America
- * E-mail:
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Yang W, Wang J, Shi L, Yu L, Qian Y, Liu Y, Wang W, Cheng S. Podocyte injury and overexpression of vascular endothelial growth factor and transforming growth factor-beta 1 in adriamycin-induced nephropathy in rats. Cytokine 2012; 59:370-6. [PMID: 22579701 DOI: 10.1016/j.cyto.2012.04.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 03/19/2012] [Accepted: 04/11/2012] [Indexed: 11/25/2022]
Abstract
The aim of this study is to investigate the expression of nephrin, vascular endothelial growth factor (VEGF), transforming growth factor-beta 1 (TGF-β1), and podocyte number in adriamycin (ADR)-induced nephropathy. A total of 60 male Sprague-Dawley rats were randomly divided into the control group and the ADR nephropathy group. The nephropathy was induced by tail-vein injection of ADR (4 mg/kg) twice at a 14-day interval. The expression levels of nephrin, VEGF, and TGF-β1 in glomeruli were assessed by immunohistochemistry and western blotting. The podocyte number was also evaluated after anti-Wilms' tumor-1 (WT1) immunohistochemical staining. In addition, the urinary protein content, biochemical parameters in serum samples and glomerular sclerosis index (SI) were compared between groups. In the ADR nephropathy group, the expression levels of nephrin was significantly decreased with the fusion of podocyte foot processes at 6 weeks after the first ADR injection, which was associated with a marked proteinuria. A decrease in podocyte number and an increase in SI with the overexpression of both VEGF and TGF-β1 were also observed in the glomeruli at 10 weeks after the first ADR injection. This was associated with focal segmental glomerulosclerosis (FSGS). The study data suggest that podocyte injury and decreased nephrin, as well as increased VEGF and TGF-β1, may contribute to the development of proteinuria and FSGS in ADR-induced nephropathy in rats.
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Affiliation(s)
- Weina Yang
- Department of Anatomy, Histology & Embryology, Medicine School of Xi'an Jiaotong University, Xi'an, PR China
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Bertuccio C, Veron D, Aggarwal PK, Holzman L, Tufro A. Vascular endothelial growth factor receptor 2 direct interaction with nephrin links VEGF-A signals to actin in kidney podocytes. J Biol Chem 2011; 286:39933-44. [PMID: 21937443 DOI: 10.1074/jbc.m111.241620] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The transmembrane protein nephrin is an essential component of slit diaphragms, the specialized cell junctions that link podocyte foot processes. Podocytes are epithelial cells that surround the glomerular capillaries in the kidney and are necessary for the organ-filtering function. Nephrin signaling complex transduces extracellular cues to the podocyte cytoskeleton and regulates podocyte shape and function. Vascular endothelial growth factor A (VEGF-A) is a required growth factor produced and secreted by podocytes. Accumulating evidence suggests a cross-talk between VEGF-A and nephrin signaling pathways. We previously showed that in vivo nephrin associates with VEGF receptor-2 (VEGFR2), the signaling receptor for VEGF-A. In the present work, we characterized the interaction between nephrin and VEGFR2 in cultured cells and in vitro. We demonstrate that nephrin-VEGFR2 interaction is direct using mass spectrometry, immunoprecipitation, GST-binding assays, and blot overlay experiments. This interaction occurs through VEGFR2 and nephrin cytoplasmic domains. Nephrin-VEGFR2 interaction is modulated by tyrosine phosphorylation of both cytoplasmic domains. Furthermore, the nephrin-VEGFR2 complex involves Nck and actin. VEGF-A signaling via this complex results in decreased cell size. We provide evidence that this multiprotein interaction occurs in cultured podocytes. We propose that the nephrin-VEGFR2 complex acts as a key mediator to transduce local VEGF-A signals to the podocyte actin cytoskeleton, regulating the foot process structure and glomerular filter integrity.
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Affiliation(s)
- Claudia Bertuccio
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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Reidy K, Tufro A. Semaphorins in kidney development and disease: modulators of ureteric bud branching, vascular morphogenesis, and podocyte-endothelial crosstalk. Pediatr Nephrol 2011; 26:1407-12. [PMID: 21336944 PMCID: PMC3397149 DOI: 10.1007/s00467-011-1769-1] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 12/12/2010] [Accepted: 01/06/2011] [Indexed: 12/14/2022]
Abstract
Semaphorins are guidance proteins that play important roles in organogenesis and disease. Expression of class 3 semaphorins and their receptors is regulated during kidney development. Gain- and loss-of-function experiments demonstrated that tight semaphorin3a gene dosage is required for podocyte differentiation, and for the establishment of a normal glomerular filtration barrier. Sema3a modulates kidney vascular patterning acting as a negative regulator of endothelial cell migration and survival. Excess podocyte semaphorin3a expression causes glomerular disease in mice. In addition, Sema3a is a negative regulator of ureteric bud branching, whereas Sema3c is a positive regulator of ureteric bud and endothelial cell branching morphogenesis. In summary, secreted semaphorins modulate ureteric bud branching, vascular patterning, and podocyte-endothelial crosstalk, suggesting that they play a role in renal disease. Understanding the signaling pathways downstream from semaphorin receptors will provide insight into the mechanism of action of semaphorins in renal pathology.
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Affiliation(s)
- Kimberly Reidy
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Alda Tufro
- Yale University School of Medicine, 333 Cedar Avenue, New Haven, CT 06520, USA
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Veron D, Bertuccio CA, Marlier A, Reidy K, Garcia AM, Jimenez J, Velazquez H, Kashgarian M, Moeckel GW, Tufro A. Podocyte vascular endothelial growth factor (Vegf₁₆₄) overexpression causes severe nodular glomerulosclerosis in a mouse model of type 1 diabetes. Diabetologia 2011; 54:1227-41. [PMID: 21318407 PMCID: PMC3397150 DOI: 10.1007/s00125-010-2034-z] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Accepted: 11/19/2010] [Indexed: 01/11/2023]
Abstract
AIMS/HYPOTHESIS The pathogenic role of excessive vascular endothelial growth factor (VEGF)-A in diabetic nephropathy has not been defined. We sought to test whether increased podocyte VEGF-A signalling determines the severity of diabetic glomerulopathy. METHODS Podocyte-specific, doxycycline-inducible Vegf₁₆₄ (the most abundant Vegfa isoform) overexpressing adult transgenic mice were made diabetic with low doses of streptozotocin and examined 12 weeks after onset of diabetes. We studied diabetic and non-diabetic transgenic mice fed a standard or doxycycline-containing diet. VEGF-A and albuminuria were measured by ELISA, creatinine was measured by HPLC, renal morphology was examined by light and electron microscopy, and gene expression was assessed by quantitative PCR, immunoblotting and immunohistochemistry. RESULTS Podocyte Vegf₁₆₄ overexpression in our mouse model of diabetes resulted in advanced diabetic glomerulopathy, characterised by Kimmelstiel-Wilson-like nodular glomerulosclerosis, microaneurysms, mesangiolysis, glomerular basement membrane thickening, podocyte effacement and massive proteinuria associated with hyperfiltration. It also led to increased VEGF receptor 2 and semaphorin3a levels, as well as nephrin and matrix metalloproteinase-2 downregulation, whereas circulating VEGF-A levels were similar to those in control diabetic mice. CONCLUSIONS/INTERPRETATION Collectively, these data demonstrate that increased podocyte Vegf₁₆₄ signalling dramatically worsens diabetic nephropathy in a streptozotocin-induced mouse model of diabetes, resulting in nodular glomerulosclerosis and massive proteinuria. This suggests that local rather than systemic VEGF-A levels determine the severity of diabetic nephropathy and that semaphorin3a signalling and matrix metalloproteinase-2 dysregulation are mechanistically involved in severe diabetic glomerulopathy.
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Affiliation(s)
- D. Veron
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar St, P.O. Box 208064, New Haven, CT 06520-8064, USA
| | - C. A. Bertuccio
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar St, P.O. Box 208064, New Haven, CT 06520-8064, USA
| | - A. Marlier
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA
| | - K. Reidy
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - A. M. Garcia
- Department of Internal Medicine, Albert Einstein College of Medicine, Bronx, NY, USA
| | - J. Jimenez
- Analytical Imaging Facility, Albert Einstein College of Medicine, Bronx, NY, USA
| | - H. Velazquez
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA
| | - M. Kashgarian
- Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - G. W. Moeckel
- Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - A. Tufro
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar St, P.O. Box 208064, New Haven, CT 06520-8064, USA
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