1
|
Ma S, Qiu Y, Zhang C. Cytoskeleton Rearrangement in Podocytopathies: An Update. Int J Mol Sci 2024; 25:647. [PMID: 38203817 PMCID: PMC10779434 DOI: 10.3390/ijms25010647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/14/2023] [Accepted: 01/01/2024] [Indexed: 01/12/2024] Open
Abstract
Podocyte injury can disrupt the glomerular filtration barrier (GFB), leading to podocytopathies that emphasize podocytes as the glomerulus's key organizer. The coordinated cytoskeleton is essential for supporting the elegant structure and complete functions of podocytes. Therefore, cytoskeleton rearrangement is closely related to the pathogenesis of podocytopathies. In podocytopathies, the rearrangement of the cytoskeleton refers to significant alterations in a string of slit diaphragm (SD) and focal adhesion proteins such as the signaling node nephrin, calcium influx via transient receptor potential channel 6 (TRPC6), and regulation of the Rho family, eventually leading to the disorganization of the original cytoskeletal architecture. Thus, it is imperative to focus on these proteins and signaling pathways to probe the cytoskeleton rearrangement in podocytopathies. In this review, we describe podocytopathies and the podocyte cytoskeleton, then discuss the molecular mechanisms involved in cytoskeleton rearrangement in podocytopathies and summarize the effects of currently existing drugs on regulating the podocyte cytoskeleton.
Collapse
Affiliation(s)
| | | | - Chun Zhang
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (S.M.); (Y.Q.)
| |
Collapse
|
2
|
Salemkour Y, Yildiz D, Dionet L, ‘t Hart DC, Verheijden KA, Saito R, Mahtal N, Delbet JD, Letavernier E, Rabant M, Karras A, van der Vlag J, Nijenhuis T, Tharaux PL, Lenoir O. Podocyte Injury in Diabetic Kidney Disease in Mouse Models Involves TRPC6-mediated Calpain Activation Impairing Autophagy. J Am Soc Nephrol 2023; 34:1823-1842. [PMID: 37678257 PMCID: PMC10631601 DOI: 10.1681/asn.0000000000000212] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 07/28/2023] [Indexed: 09/09/2023] Open
Abstract
SIGNIFICANCE STATEMENT Autophagy protects podocytes from injury in diabetic kidney disease (DKD). Restoring glomerular autophagy is a promising approach to limit DKD. This study demonstrates a novel regulatory mechanism of autophagy that blocks this critical protection of the glomerular filtration barrier. We demonstrated that TRPC6 induced in podocytes in mouse models of diabetes mediates calpain activation, thereby impairing podocyte autophagy, causing injury and accelerating DKD. Furthermore, this study provides proof of principle for druggable targets for DKD because restoration of podocyte autophagy by calpain inhibitors effectively limits glomerular destruction. BACKGROUND Diabetic kidney disease is associated with impaired podocyte autophagy and subsequent podocyte injury. The regulation of podocyte autophagy is unique because it minimally uses the mTOR and AMPK pathways. Thus, the molecular mechanisms underlying the impaired autophagy in podocytes in diabetic kidney disease remain largely elusive. METHODS This study investigated how the calcium channel TRPC6 and the cysteine protease calpains deleteriously affect podocyte autophagy in diabetic kidney disease in mice. We demonstrated that TRPC6 knockdown in podocytes increased the autophagic flux because of decreased cysteine protease calpain activity. Diabetic kidney disease was induced in vivo using streptozotocin with unilateral nephrectomy and the BTBR ob/ob mouse models. RESULTS Diabetes increased TRPC6 expression in podocytes in vivo with decreased podocyte autophagic flux. Transgenic overexpression of the endogenous calpain inhibitor calpastatin, as well as pharmacologic inhibition of calpain activity, normalized podocyte autophagic flux, reduced nephrin loss, and prevented the development of albuminuria in diabetic mice. In kidney biopsies from patients with diabetes, we further confirmed that TRPC6 overexpression in podocytes correlates with decreased calpastatin expression, autophagy blockade, and podocyte injury. CONCLUSIONS Overall, we discovered a new mechanism that connects TRPC6 and calpain activity to impaired podocyte autophagy, increased podocyte injury, and development of proteinuria in the context of diabetic kidney disease. Therefore, targeting TRPC6 and/or calpain to restore podocyte autophagy might be a promising therapeutic strategy for diabetic kidney disease.
Collapse
Affiliation(s)
| | - Dilemin Yildiz
- Department of Nephrology, Research Institute of Medical Innovations, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Léa Dionet
- Université Paris Cité, Inserm, PARCC, Paris, France
| | - Daan C. ‘t Hart
- Department of Nephrology, Research Institute of Medical Innovations, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Kim A.T. Verheijden
- Department of Nephrology, Research Institute of Medical Innovations, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Ryuta Saito
- Discovery Technology Laboratories, Sohyaku, Innovative Research Division, Mitsubishi Tanabe Pharma Corporation, Yokohama, Japan
| | | | - Jean-Daniel Delbet
- Université Paris Cité, Inserm, PARCC, Paris, France
- Pediatric Nephrology Department, Armand Trousseau Hospital, DMU Origyne, APHP, Paris and French Reference Center for Rare Diseases MARHEA, Paris, France
| | - Emmanuel Letavernier
- Sorbonne Université, Hôpital Tenon, Paris, France
- INSERM UMR S 1155, Hôpital Tenon, Paris, France
- Explorations Fonctionnelles Multidisciplinaires, AP-HP, Hôpital Tenon, Paris, France
| | - Marion Rabant
- Pathology Department, Necker-Enfants Malades Hospital - Paris, Paris, France
| | - Alexandre Karras
- Université Paris Cité, Inserm, PARCC, Paris, France
- Nephrology Unit, Georges Pompidou European Hospital - Paris, Paris, France
| | - Johan van der Vlag
- Department of Nephrology, Research Institute of Medical Innovations, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Tom Nijenhuis
- Department of Nephrology, Research Institute of Medical Innovations, Radboud University Medical Centre, Nijmegen, The Netherlands
| | | | | |
Collapse
|
3
|
Fu Y, Xiang Y, Li H, Chen A, Dong Z. Inflammation in kidney repair: Mechanism and therapeutic potential. Pharmacol Ther 2022; 237:108240. [PMID: 35803367 DOI: 10.1016/j.pharmthera.2022.108240] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/29/2022] [Accepted: 06/30/2022] [Indexed: 02/07/2023]
Abstract
The kidney has a remarkable ability of repair after acute kidney injury (AKI). However, when injury is severe or persistent, the repair is incomplete or maladaptive and may lead to chronic kidney disease (CKD). Maladaptive kidney repair involves multiple cell types and multifactorial processes, of which inflammation is a key component. In the process of inflammation, there is a bidirectional interplay between kidney parenchymal cells and the immune system. The extensive and complex crosstalk between renal tubular epithelial cells and interstitial cells, including immune cells, fibroblasts, and endothelial cells, governs the repair and recovery of the injured kidney. Further research in this field is imperative for the discovery of biomarkers and promising therapeutic targets for kidney repair. In this review, we summarize the latest progress in the immune response and inflammation during maladaptive kidney repair, analyzing the interaction between immune cells and intrinsic kidney cells, pointing out the potentialities of inflammation-related pathways as therapeutic targets, and discussing the challenges and future research prospects in this field.
Collapse
Affiliation(s)
- Ying Fu
- Department of Nephrology, Hunan Key Laboratory of Kidney Disease and Blood Purification, The Second Xiangya Hospital at Central South University, Changsha 410011, China
| | - Yu Xiang
- Department of Nephrology, Hunan Key Laboratory of Kidney Disease and Blood Purification, The Second Xiangya Hospital at Central South University, Changsha 410011, China
| | - Honglin Li
- Department of Nephrology, Hunan Key Laboratory of Kidney Disease and Blood Purification, The Second Xiangya Hospital at Central South University, Changsha 410011, China
| | - Anqun Chen
- Department of Nephrology, Hunan Key Laboratory of Kidney Disease and Blood Purification, The Second Xiangya Hospital at Central South University, Changsha 410011, China
| | - Zheng Dong
- Department of Nephrology, Hunan Key Laboratory of Kidney Disease and Blood Purification, The Second Xiangya Hospital at Central South University, Changsha 410011, China; Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood VA Medical Center, Augusta, GA, USA.
| |
Collapse
|
4
|
Semenikhina M, Stefanenko M, Spires DR, Ilatovskaya DV, Palygin O. Nitric-Oxide-Mediated Signaling in Podocyte Pathophysiology. Biomolecules 2022; 12:biom12060745. [PMID: 35740870 PMCID: PMC9221338 DOI: 10.3390/biom12060745] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/16/2022] [Accepted: 05/23/2022] [Indexed: 11/23/2022] Open
Abstract
Nitric oxide (NO) is a potent signaling molecule involved in many physiological and pathophysiological processes in the kidney. NO plays a complex role in glomerular ultrafiltration, vasodilation, and inflammation. Changes in NO bioavailability in pathophysiological conditions such as hypertension or diabetes may lead to podocyte damage, proteinuria, and rapid development of chronic kidney disease (CKD). Despite the extensive data highlighting essential functions of NO in health and pathology, related signaling in glomerular cells, particularly podocytes, is understudied. Several reports indicate that NO bioavailability in glomerular cells is decreased during the development of renal pathology, while restoring NO level can be beneficial for glomerular function. At the same time, the compromised activity of nitric oxide synthase (NOS) may provoke the formation of peroxynitrite and has been linked to autoimmune diseases such as systemic lupus erythematosus. It is known that the changes in the distribution of NO sources due to shifts in NOS subunits expression or modifications of NADPH oxidases activity may be linked to or promote the development of pathology. However, there is a lack of information about the detailed mechanisms describing the production and release of NO in the glomerular cells. The interaction of NO and other reactive oxygen species in podocytes and how NO-calcium crosstalk regulates glomerular cells’ function is still largely unknown. Here, we discuss recent reports describing signaling, synthesis, and known pathophysiological mechanisms mediated by the changes in NO homeostasis in the podocyte. The understanding and further investigation of these essential mechanisms in glomerular cells will facilitate the design of novel strategies to prevent or manage health conditions that cause glomerular and kidney damage.
Collapse
Affiliation(s)
- Marharyta Semenikhina
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA; (M.S.); (M.S.)
| | - Mariia Stefanenko
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA; (M.S.); (M.S.)
| | - Denisha R. Spires
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA; (D.R.S.); (D.V.I.)
| | - Daria V. Ilatovskaya
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA; (D.R.S.); (D.V.I.)
| | - Oleg Palygin
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA; (M.S.); (M.S.)
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425, USA
- Correspondence:
| |
Collapse
|
5
|
Liu R, Zhang W, Cai J, Lin W, Zheng Q, Wu Y. USP22 Mediates High Glucose-Induced Injury and Epithelial-Mesenchymal Transition in Podocytes via Regulating the RIPK3/MLKL Signaling Pathway. J HARD TISSUE BIOL 2022. [DOI: 10.2485/jhtb.31.187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Renhua Liu
- Department of Nephrology, Huizhou Municipal Central Hospital
| | | | - Jun Cai
- Department of Nephrology, Huizhou Municipal Central Hospital
| | - Weiping Lin
- Department of Nephrology, Huizhou Municipal Central Hospital
| | - Qingfa Zheng
- Department of Nephrology, Huizhou Municipal Central Hospital
| | - Yong Wu
- Department of Nephrology, Huizhou Municipal Central Hospital
| |
Collapse
|
6
|
Xiong Y, Zhu W, Xu Q, Ruze R, Yan Z, Li J, Hu S, Zhong M, Cheng Y, Zhang G. Sleeve Gastrectomy Attenuates Diabetic Nephropathy by Upregulating Nephrin Expressions in Diabetic Obese Rats. Obes Surg 2021; 30:2893-2904. [PMID: 32399849 DOI: 10.1007/s11695-020-04611-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
PURPOSE Diabetic nephropathy (DN) is the leading cause of end-stage renal disease, and sleeve gastrectomy (SG) is considered to be an effective strategy to improve pre-existing DN. However, the mechanism remains unknown. MATERIALS AND METHODS Animal model of DN was induced by high-fat diet (HFD) and streptozotocin (STZ). SG or sham surgery was performed and rats were sacrificed at 4, 8, and 12 weeks after surgery. The basic parameters (blood glucose, body weight, kidney weight), indicators of renal function including serum creatinine (Scr), blood urea nitrogen (BUN), urine microalbumin, urine creatinine (Ucr), microalbumin creatinine ratio (UACR), ultrastructural changes of glomerulus, and the expression of nephrin gene and protein in glomerular podocytes were compared among groups. RESULTS Blood glucose and body weight of SG rats were significantly lower than those of the sham-operated rats, and renal function of SG groups were also significantly improved within the postoperative period of 12 weeks. The results of periodic acid-Schiff staining (PAS) and transmission electron microscopy (TEM) showed that glomerular hypertrophy and accumulation of extracellular matrix proteins were significantly alleviated after SG, and the thickness of basement membrane and the fusion or effacement of foot processes were also significantly improved. The mRNA and protein expression of nephrin in SG groups was significantly higher than that in the sham group. CONCLUSION These results suggest that SG attenuates DN by upregulating the expression of nephrin and improving the ultrastructure of glomerular filtration membrane. This study indicates that SG can be used as an available therapeutic intervention for DN.
Collapse
Affiliation(s)
- Yacheng Xiong
- Department of General Surgery, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, 250014, Shandong Province, People's Republic of China
| | - Wei Zhu
- Shandong Medical College, Jucai 6# Road, Linyi, 276000, Shandong Province, People's Republic of China
| | - Qian Xu
- Department of General Surgery, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, 250014, Shandong Province, People's Republic of China
| | - Rexiati Ruze
- Department of General Surgery, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, 250014, Shandong Province, People's Republic of China
| | - Zhibo Yan
- Department of General Surgery, Qilu Hospital of Shandong University, Jinan, 250012, Shandong Province, People's Republic of China
| | - Jianwen Li
- Department of General Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200025, People's Republic of China
| | - Sanyuan Hu
- Department of General Surgery, The First Affiliated Hospital of Shandong First Medical University, 16766#, Jingshi Road, Jinan, 250014, Shandong Province, China
| | - Mingwei Zhong
- Department of General Surgery, The First Affiliated Hospital of Shandong First Medical University, 16766#, Jingshi Road, Jinan, 250014, Shandong Province, China
| | - Yugang Cheng
- Department of General Surgery, The First Affiliated Hospital of Shandong First Medical University, 16766#, Jingshi Road, Jinan, 250014, Shandong Province, China
| | - Guangyong Zhang
- Department of General Surgery, The First Affiliated Hospital of Shandong First Medical University, 16766#, Jingshi Road, Jinan, 250014, Shandong Province, China.
| |
Collapse
|
7
|
Qi C, Alsomali F, Zhong J, Harris RC, Kon V, Yang H, Fogo AB. Increased dishevelled associated activator of morphogenesis 2, a new podocyte-associated protein, in diabetic nephropathy. Nephrol Dial Transplant 2021; 36:1006-1016. [PMID: 33544843 DOI: 10.1093/ndt/gfab014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 01/05/2021] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Previously, by using proteomic analysis and RNA sequencing in isolated glomeruli, we identified several novel differentially expressed proteins in human and mouse diabetic nephropathy (DN) versus controls, including dishevelled associated activator of morphogenesis 2 (DAAM2). DAAM2 binds the Wnt effector Dvl. We aimed to study possible contributions of DAAM2 to DN. METHODS We assessed DAAM2 by immunostaining in non-cancer regions of human nephrectomy (Nx), DN and normal donor kidney tissues. We also examined DAAM2 in DN mice (db/db eNOS-/-) and Nx mice. DN mice treated with angiotensin-converting enzyme inhibitor (ACEI), dipeptidyl peptidase 4 inhibitor (DPP4I) or vehicle were compared. DAAM2 was knocked down in primary cultured podocytes by small interfering RNA to study its effects on cell function. RESULTS In normal human glomeruli, DAAM2 was expressed only on podocytes. DAAM2 expression was increased in both Nx and DN versus normal donors. Podocyte DAAM2 expression was increased in DN and Nx mouse models. Glomerular DAAM2 expression correlated with glomerular size and was decreased significantly by ACEI while DPP4I only numerically reduced DAAM2. In primary cultured podocytes, knockdown of DAAM2 enhanced adhesion, slowed migration, activated Wnt-β-catenin signaling and downregulated mammalian target of rapamycin complex 1 (mTORC1) and Rho activity. CONCLUSIONS Podocyte DAAM2 is upregulated in both Nx and DN, which could be contributed to by glomerular hypertrophy. We hypothesize that DAAM2 regulates podocyte function through the mTORC1, Wnt/β-catenin and Rho signaling pathways.
Collapse
Affiliation(s)
- Chenyang Qi
- Department of Pathology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Faten Alsomali
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Jinyong Zhong
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.,Division of Pediatric Nephrology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Raymond C Harris
- Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Valentina Kon
- Division of Pediatric Nephrology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Haichun Yang
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.,Division of Pediatric Nephrology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.,Division of Pediatric Nephrology, Vanderbilt University Medical Center, Nashville, TN, USA.,Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN, USA
| |
Collapse
|
8
|
Li Y, Pan Y, Cao S, Sasaki K, Wang Y, Niu A, Fan X, Wang S, Zhang MZ, Harris RC. Podocyte EGFR Inhibits Autophagy Through Upregulation of Rubicon in Type 2 Diabetic Nephropathy. Diabetes 2021; 70:562-576. [PMID: 33239448 PMCID: PMC7881855 DOI: 10.2337/db20-0660] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 11/17/2020] [Indexed: 02/06/2023]
Abstract
Renal epidermal growth factor receptor (EGFR) signaling is activated in models of diabetic nephropathy (DN), and inhibition of the EGFR signaling pathway protects against the development of DN. We have now determined that in cultured podocytes, high glucose led to increases in activation of EGFR signaling but decreases in autophagy activity as indicated by decreased beclin-1 and inhibition of LC3B autophagosome formation as well as increased rubicon (an autophagy inhibitor) and SQSTM1 (autophagy substrate). Either genetic (small interfering [si]EGFR) or pharmacologic (AG1478) inhibition of EGFR signaling attenuated the decreased autophagy activity. In addition, rubicon siRNA knockdown prevented high glucose-induced inhibition of autophagy in podocytes. We further examined whether selective EGFR deletion in podocytes affected the progression of DN in type 2 diabetes. Selective podocyte EGFR deletion had no effect on body weight or fasting blood sugars in either db/db mice or nos3 -/-; db/db mice, a model of accelerated type 2 DN. However selective podocyte EGFR deletion led to relative podocyte preservation and marked reduction in albuminuria and glomerulosclerosis, renal proinflammatory cytokine/chemokine expression, and decreased profibrotic and fibrotic components in nos3 -/-; db/db mice. Podocyte EGFR deletion led to decreased podocyte expression of rubicon, in association with increased podocyte autophagy activity. Therefore, activation of EGFR signaling in podocytes contributes to progression of DN at least in part by increasing rubicon expression, leading to subsequent autophagy inhibition and podocyte injury.
Collapse
Affiliation(s)
- Yan Li
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
- Division of Nephrology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yu Pan
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
- Division of Nephrology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shirong Cao
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Kensuke Sasaki
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Yinqiu Wang
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Aolei Niu
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Xiaofeng Fan
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Suwan Wang
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Ming-Zhi Zhang
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
| | - Raymond C Harris
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
- Vanderbilt Center for Kidney Disease, Vanderbilt University School of Medicine, Nashville, TN
- Department of Veterans Affairs, Nashville, TN
| |
Collapse
|
9
|
Ishii H, Kaneko S, Yanai K, Aomatsu A, Hirai K, Ookawara S, Ishibashi K, Morishita Y. MicroRNAs in Podocyte Injury in Diabetic Nephropathy. Front Genet 2020; 11:993. [PMID: 33193581 PMCID: PMC7477342 DOI: 10.3389/fgene.2020.00993] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 08/05/2020] [Indexed: 12/24/2022] Open
Abstract
Diabetic nephropathy is one of the major complications of diabetes mellitus and is the leading cause of end-stage renal disease worldwide. Podocyte injury contributes to the development of diabetic nephropathy. However, the molecules that regulate podocyte injury in diabetic nephropathy have not been fully clarified. MicroRNAs (miRNAs) are small non-coding RNAs that can inhibit the translation of target messenger RNAs. Previous reports have described alteration of the expression levels of many miRNAs in cultured podocyte cells stimulated with a high glucose concentration and podocytes in rodent models of diabetic nephropathy. The associations between podocyte injury and miRNA expression levels in blood, urine, and kidney in patients with diabetic nephropathy have also been reported. Moreover, modulation of the expression of several miRNAs has been shown to have protective effects against podocyte injury in diabetic nephropathy in cultured podocyte cells in vitro and in rodent models of diabetic nephropathy in vivo. Therefore, this review focuses on miRNAs in podocyte injury in diabetic nephropathy, with regard to their potential as biomarkers and miRNA modulation as a therapeutic option.
Collapse
Affiliation(s)
- Hiroki Ishii
- Division of Nephrology, First Department of Integrated Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Shohei Kaneko
- Division of Nephrology, First Department of Integrated Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Katsunori Yanai
- Division of Nephrology, First Department of Integrated Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Akinori Aomatsu
- Division of Nephrology, First Department of Integrated Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Keiji Hirai
- Division of Nephrology, First Department of Integrated Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Susumu Ookawara
- Division of Nephrology, First Department of Integrated Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Kenichi Ishibashi
- Department of Medical Physiology, Meiji Pharmaceutical University, Kiyose, Japan
| | - Yoshiyuki Morishita
- Division of Nephrology, First Department of Integrated Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| |
Collapse
|
10
|
Abstract
Long noncoding RNAs (lncRNAs) are a group of noncoding RNAs that are longer than 200 nucleotides without protein-coding potential. Becasuse of which these RNAs have no significant protein-coding potential, they were initially considered as "junk-products" of transcription without biological meaning. Nevertheless, recent research advancements have shown that lncRNAs are involved in many physiological processes such as cell cycle regulation, cell apoptosis and survival, cancer migration and metabolism. This review described the function of lncRNAs and the potential underlying mechanism involved in diabetes and diabetic microvascular complications. The roles of lncRNAs in the pathogenesis of type 2 diabetes mellitus have only recently been recognized, involving hepatic glucose production and insulin resistance. We further investigated the mechanisms of lncRNAs in diabetic nephropathy (DN), including the roles of lncRNAs in mesangial cells (MCs) proliferation and fibrosis, inflammatory processes, extracellular matrix accumulation in the glomeruli and tubular injury. We also discussed the potential mechanism of lncRNAs in diabetic retinopathy (DR), including aberrant neovascularization and neuronal dysfunction. This review summarized the current knowledge of the functions and underlying mechanisms of lncRNAs in type 2 diabetes mellitus and related renal and retinal complications. Accumulating evidence suggests the potential of lncRNAs as therapeutic targets for clinical applications in the management of diabetes.
Collapse
Affiliation(s)
- Yanxia Chen
- Department of Endocrinology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050000, PR China
| | - Yinxi He
- Department of Orthopaedic Trauma, The Third Hospital of Shijiazhuang, Shijiazhuang, Hebei, 050000, PR China
| | - Hong Zhou
- Department of Endocrinology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050000, PR China
| |
Collapse
|
11
|
Guo J, Han J, Liu J, Wang S. MicroRNA-770-5p contributes to podocyte injury via targeting E2F3 in diabetic nephropathy. ACTA ACUST UNITED AC 2020; 53:e9360. [PMID: 32696822 PMCID: PMC7372943 DOI: 10.1590/1414-431x20209360] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 04/06/2020] [Indexed: 11/21/2022]
Abstract
Diabetic nephropathy (DN) has been identified as the major cause of end-stage
renal disease (ESRD) in most developed countries. MicroRNA-770-5p depletion
could repress high glucose (HG)-triggered apoptosis in podocytes, and
downregulation of E2F transcription factor 3 (E2F3) could facilitate podocyte
injury. Nevertheless, whether E2F3 is involved in miR-770-5p knockdown-mediated
improvement of DN is still unclear. The expression levels of miR-770-5p and E2F3
were detected in HG-treated podocytes by RT-qPCR. The expression levels of E2F3,
apoptosis-related proteins Bcl-2 related X protein (Bax), B-cell lymphoma-2
(Bcl-2), Bad, apoptotic peptidase activating factor 1 (APAF1), C-caspase3,
C-caspase7, and C-caspase9 were detected by western blot assay. The effects of
miR-770-5p and E2F3 on HG-treated podocytes proliferation and apoptosis were
detected by CCK-8 and flow cytometry assays. The interaction between miR-770-5p
and E2F3 was predicted by Targetscan, and then verified by the dual-luciferase
reporter assay. MiR-770-5p was upregulated and E2F3 was downregulated in
HG-treated podocytes. MiR-770-5p inhibited proliferation and promoted apoptosis
and E2F3 promoted proliferation and suppressed apoptosis in HG-treated
podocytes. E2F3 is a target gene of miR-770-5p and it partially abolished the
effect of miR-770-5p in HG-triggered proliferation and apoptosis of podocytes.
MiR-770-5p deficiency blocked HG-induced APAF1/caspase9 pathway via targeting
E2F3 in podocytes. We firstly confirmed that E2F3 was a target of miR-770-5p in
podocytes. These findings suggested that miR-770-5p expedited podocyte injury by
targeting E2F3, and the miR-770-5p/E2F3 axis might represent a pathological
mechanism of DN progression.
Collapse
Affiliation(s)
- Juanjuan Guo
- Department of Geriatric Ward, Heping Hospital Affiliated to Changzhi Medical College, Shanxi, China
| | - Jie Han
- Department of Physical Examination Center, Heping Hospital Affiliated to Changzhi Medical College, Shanxi, China
| | - Jieying Liu
- Department of Geriatric Ward, Heping Hospital Affiliated to Changzhi Medical College, Shanxi, China
| | - Shaoli Wang
- Department of Geriatric Ward, Heping Hospital Affiliated to Changzhi Medical College, Shanxi, China
| |
Collapse
|
12
|
Jing F, Zhao J, Jing X, Lei G. Long noncoding RNA Airn protects podocytes from diabetic nephropathy lesions via binding to Igf2bp2 and facilitating translation of Igf2 and Lamb2. Cell Biol Int 2020; 44:1860-1869. [PMID: 32437062 DOI: 10.1002/cbin.11392] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 04/07/2020] [Accepted: 05/18/2020] [Indexed: 01/08/2023]
Abstract
Diabetic nephropathy (DN) is a severe diabetic microvascular complication with high mortality. Long noncoding RNAs (lncRNAs) are characterized as important regulators of various biological processes by emerging researches, whereas the molecular mechanisms by which lncRNAs participate in DN progression need to be further clarified. Herein, we conducted a study on the regulatory role in DN of an lncRNA named antisense of Igf2r non-protein-coding RNA (Airn). Airn expression was downregulated in renal tissues of diabetic mice, and was negatively related with DN development. Besides, Airn downregulation was detected in high-glucose-stimulated podocytes, resulting in poorer cell viability, a higher tendency to cell apoptosis, and a deficiency of laminin level, while Airn overexpression could significantly alleviate these deleterious effects. Mechanistically, using RNA immunoprecipitation and RNA pull-down assays, we found that Airn could bind to the RNA-binding protein Igf2bp2, thus facilitating translation of Igf2 and Lamb2 to maintain normal podocyte viability and glomerular barrier function. Collectively, our results demonstrate the protective role of lncRNA Airn in podocytes against DN, providing a new insight into DN pathogenesis and molecular therapy.
Collapse
Affiliation(s)
- Fengying Jing
- Department of Integrated TCM and Western Medicine, Shaanxi Tuberculosis Control Hospital (Shaanxi Fifth People's Hospital), Xi'an, Shaanxi, China
| | - Jin Zhao
- Department of Nephrology, Zibo First Hospital, Zibo, Shandong, China
| | - Xu Jing
- Department of Endocrinology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Gao Lei
- Department of Endocrinology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| |
Collapse
|
13
|
Khokhar M, Roy D, Modi A, Agarwal R, Yadav D, Purohit P, Sharma P. Perspectives on the role of PTEN in diabetic nephropathy: an update. Crit Rev Clin Lab Sci 2020; 57:470-483. [PMID: 32306805 DOI: 10.1080/10408363.2020.1746735] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Phosphatase and tensin homolog (PTEN) is a potent tumor suppressor gene that antagonizes the proto-oncogenic phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) signaling pathway and governs basic cellular metabolic processes. Recently, its role in cell growth, metabolism, architecture, and motility as an intramolecular and regulatory mediator has gained widespread research interest as it applies to non-tumorous diseases, such as insulin resistance (IR) and diabetic nephropathy (DN). DN is characterized by renal tubulointerstitial fibrosis (TIF) and epithelial-mesenchymal transition (EMT), and PTEN plays a significant role in the regulation of both. Epigenetics and microRNAs (miRNAs) are novel players in post-transcriptional regulation and research evidence demonstrates that they reduce the expression of PTEN by acting as key regulators of autophagy and TIF through activation of the Akt/mammalian target of rapamycin (mTOR) signaling pathway. These regulatory processes might play an important role in solving the complexities of DN pathogenesis and IR, as well as the therapeutic management of DN with the help of PTEN K27-linked polyubiquitination. Currently, there are no comprehensive reviews citing the role PTEN plays in the development of DN and its regulation via miRNA and epigenetic modifications. The present review explores these facets of PTEN in the pathogenesis of IR and DN.
Collapse
Affiliation(s)
- Manoj Khokhar
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Dipayan Roy
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Anupama Modi
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Riddhi Agarwal
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Dharmveer Yadav
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Purvi Purohit
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Praveen Sharma
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| |
Collapse
|
14
|
Bissler JJ, Budde K, Sauter M, Franz DN, Zonnenberg BA, Frost MD, Belousova E, Berkowitz N, Ridolfi A, Christopher Kingswood J. Effect of everolimus on renal function in patients with tuberous sclerosis complex: evidence from EXIST-1 and EXIST-2. Nephrol Dial Transplant 2020; 34:1000-1008. [PMID: 30053159 PMCID: PMC6545468 DOI: 10.1093/ndt/gfy132] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Indexed: 02/06/2023] Open
Abstract
Background A reduction in renal angiomyolipoma volume observed with everolimus (EVE) treatment in patients with tuberous sclerosis complex (TSC) has been postulated to translate to clinical benefit by reducing the risk of renal hemorrhage and chronic renal failure. Methods The long-term effects of EVE on renal function (∼4 years of treatment) were examined in patients treated with EVE in the Phase 3 EXIST-1 and EXIST-2 studies. Patients in EXIST-1 had TSC and subependymal giant cell astrocytoma (SEGA), and patients in EXIST-2 had renal angiomyolipoma and a definite diagnosis of TSC or sporadic lymphangioleiomyomatosis. EVE was administered at 4.5 mg/m2/day, with adjustment to achieve target trough levels of 5–15 ng/mL in EXIST-1 and at 10 mg/day in EXIST-2. Estimated glomerular filtration rate (eGFR) and creatinine levels were assessed at baseline, at Weeks 2, 4, 6, 8, 12 and 18, then every 3 months thereafter. Proteinuria was graded according to National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. Results A total of 111 patients from EXIST-1 and 112 patients from EXIST-2 were included in this analysis. Respective mean ages at EVE initiation were 10.5 [standard deviation (SD) 6.45] and 33.2 (SD 10.29) years, and 3.6% and 37.5% of patients had undergone prior renal intervention. Mean baseline eGFR was 115 and 88 mL/min/1.73 m2 in EXIST-1 and EXIST-2, respectively. Overall, mean eGFR remained stable over time in both studies, with an decline in renal function mostly confined to some patients with severely compromised renal function before treatment. Patients with prior renal intervention exhibited low eGFR values throughout the study. The incidence of proteinuria increased after initiating treatment with EVE and was mostly Grade 1/2 in severity, with Grade 3 proteinuria reported in only two patients. Measurements of proteinuria were limited by the use of urine dipstick tests. Conclusions The use of EVE does not appear to be nephrotoxic in patients with SEGA or renal angiomyolipoma associated with TSC and may preserve renal function in most patients. ClinicalTrials.gov identifiers NCT00789828 and NCT00790400
Collapse
Affiliation(s)
- John J Bissler
- St. Jude Children's Research Hospital and Le Bonheur Children's Hospital, Memphis, TN, USA
| | | | - Matthias Sauter
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - David N Franz
- Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | | | | | - Elena Belousova
- Moscow Research and Clinical Institute of Pediatrics, Moscow, Russian Federation
| | | | | | | |
Collapse
|
15
|
Li J, Sun YBY, Chen W, Fan J, Li S, Qu X, Chen Q, Chen R, Zhu D, Zhang J, Wu Z, Chi H, Crawford S, Oorschot V, Puelles VG, Kerr PG, Ren Y, Nilsson SK, Christian M, Tang H, Chen W, Bertram JF, Nikolic-Paterson DJ, Yu X. Smad4 promotes diabetic nephropathy by modulating glycolysis and OXPHOS. EMBO Rep 2020; 21:e48781. [PMID: 31916354 DOI: 10.15252/embr.201948781] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 10/31/2019] [Accepted: 11/18/2019] [Indexed: 02/06/2023] Open
Abstract
Diabetic nephropathy (DN) is the leading cause of end-stage kidney disease. TGF-β1/Smad3 signalling plays a major pathological role in DN; however, the contribution of Smad4 has not been examined. Smad4 depletion in the kidney using anti-Smad4 locked nucleic acid halted progressive podocyte damage and glomerulosclerosis in mouse type 2 DN, suggesting a pathogenic role of Smad4 in podocytes. Smad4 is upregulated in human and mouse podocytes during DN. Conditional Smad4 deletion in podocytes protects mice from type 2 DN, independent of obesity. Mechanistically, hyperglycaemia induces Smad4 localization to mitochondria in podocytes, resulting in reduced glycolysis and oxidative phosphorylation and increased production of reactive oxygen species. This operates, in part, via direct binding of Smad4 to the glycolytic enzyme PKM2 and reducing the active tetrameric form of PKM2. In addition, Smad4 interacts with ATPIF1, causing a reduction in ATPIF1 degradation. In conclusion, we have discovered a mitochondrial mechanism by which Smad4 causes diabetic podocyte injury.
Collapse
Affiliation(s)
- Jinhua Li
- Shunde Women and Children Hospital, Guangdong Medical University, Shunde, Guangdong, China.,The Second Clinical College, Guangdong Medical University, Dongguan, Guangdong, China.,Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Vic., Australia.,Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Vic., Australia.,Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Key Laboratory of Nephrology, National Health Commission and Guangdong Province, Guangzhou, China
| | - Yu Bo Yang Sun
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Vic., Australia
| | - Weiyi Chen
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Vic., Australia
| | - Jinjin Fan
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Key Laboratory of Nephrology, National Health Commission and Guangdong Province, Guangzhou, China
| | - Songhui Li
- Biomedical Manufacturing Commonwealth Scientific and Industrial Research Organisation (CSIRO), Melbourne, Vic., Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, Vic., Australia
| | - Xinli Qu
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Vic., Australia
| | - Qikang Chen
- Shunde Women and Children Hospital, Guangdong Medical University, Shunde, Guangdong, China
| | - Riling Chen
- Shunde Women and Children Hospital, Guangdong Medical University, Shunde, Guangdong, China
| | - Dajian Zhu
- Shunde Women and Children Hospital, Guangdong Medical University, Shunde, Guangdong, China
| | - Jinfeng Zhang
- Shunde Women and Children Hospital, Guangdong Medical University, Shunde, Guangdong, China
| | - Zhuguo Wu
- The Second Clinical College, Guangdong Medical University, Dongguan, Guangdong, China
| | - Honggang Chi
- The Second Clinical College, Guangdong Medical University, Dongguan, Guangdong, China
| | - Simon Crawford
- Monash Ramaciotti Cryo EM Platform, Monash Biomedicine Discovery Institute, Clayton, Vic., Australia
| | - Viola Oorschot
- Monash Ramaciotti Cryo EM Platform, Monash Biomedicine Discovery Institute, Clayton, Vic., Australia
| | - Victor G Puelles
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Vic., Australia.,III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Departments of Nephrology and Medicine, Monash Health and Monash University, Clayton, Vic., Australia
| | - Peter G Kerr
- Departments of Nephrology and Medicine, Monash Health and Monash University, Clayton, Vic., Australia
| | - Yi Ren
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, USA
| | - Susan K Nilsson
- Biomedical Manufacturing Commonwealth Scientific and Industrial Research Organisation (CSIRO), Melbourne, Vic., Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, Vic., Australia
| | - Mark Christian
- School of Science and Technology, Nottingham Trent University, Clifton, Nottingham, UK
| | - Huanwen Tang
- Dongguan Key Laboratory of Environmental Medicine, Department of Preventive Medicine, School of Public Health, Guangdong Medical University, Dongguan, Guangdong, China
| | - Wei Chen
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Key Laboratory of Nephrology, National Health Commission and Guangdong Province, Guangzhou, China
| | - John F Bertram
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Vic., Australia
| | - David J Nikolic-Paterson
- Departments of Nephrology and Medicine, Monash Health and Monash University, Clayton, Vic., Australia
| | - Xueqing Yu
- Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China
| |
Collapse
|
16
|
Wu M, Li S, Yu X, Chen W, Ma H, Shao C, Zhang Y, Zhang A, Huang S, Jia Z. Mitochondrial activity contributes to impaired renal metabolic homeostasis and renal pathology in STZ-induced diabetic mice. Am J Physiol Renal Physiol 2019; 317:F593-F605. [PMID: 31268353 DOI: 10.1152/ajprenal.00076.2019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Diabetic nephropathy (DN) has become the main cause of end-stage renal disease worldwide, but the efficacy of current therapeutic strategies on DN remains unsatisfactory. Recent research has reported the involvement of metabolic rearrangement in the pathological process of DN, and of all the disturbances in metabolism, mitochondria serve as key regulatory hubs. In the present study, high-resolution mass spectrometry-based nontarget metabolomics was used to uncover the metabolic characteristics of the early diabetic kidney with or without the inhibition of mitochondrial activity. At first, we observed a moderate enhancement of mitochondrial complex-1 activity in the diabetic kidney, which was completely normalized by the specific mitochondrial complex-1 inhibitor rotenone (ROT). Meanwhile, metabolomics data indicated an overactivated pentose phosphate pathway, purine and pyrimidine metabolism, hexosamine biosynthetic pathway, and tricarboxylic acid cycle, which were strikingly corrected by ROT. In addition, ROT also strikingly corrected imbalanced redox homeostasis, possibly by increasing the ratio of antioxidant metabolites glutathione and NADPH against their oxidative form. In agreement with the improved metabolic status and oxidative response, ROT attenuated glomerular and tubular injury efficiently. Fibrotic markers (fibronectin, α-smooth muscle actin, collagen type I, and collagen type III), inflammatory factors (TNF-α, IL-1β, and ICAM-1), and oxidative stress were all markedly blocked by ROT. In vitro, ROT dose dependently attenuated high glucose-induced proliferation and extracellular matrix production in mesangial cells. Collectively, these findings revealed that the overactivation of mitochondrial activity in the kidney could contribute to metabolic disorders and the pathogenesis of early DN.
Collapse
Affiliation(s)
- Mengqiu Wu
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Kidney Diseases, Beijing, China
| | - Shuzhen Li
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Xiaowen Yu
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Weiyi Chen
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Haoyang Ma
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Chang Shao
- College of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Yue Zhang
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Aihua Zhang
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Songming Huang
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
| | - Zhanjun Jia
- Department of Nephrology, Children’s Hospital of Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing,China
- Nanjing Key Laboratory of Pediatrics, Children’s Hospital of Nanjing Medical University, Nanjing, China
| |
Collapse
|
17
|
Chen Y, Zhang L, Liu S, Yao B, Zhang H, Liang S, Ma J, Liang X, Shi W. Sam68 mediates high glucose‑induced podocyte apoptosis through modulation of Bax/Bcl‑2. Mol Med Rep 2019; 20:3728-3734. [PMID: 31485651 PMCID: PMC6755155 DOI: 10.3892/mmr.2019.10601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 03/20/2019] [Indexed: 02/06/2023] Open
Abstract
Hyperglycemia promotes podocyte apoptosis and contributes to the pathogenesis of diabetic nephropathy (DN). However, the mechanisms of hyperglycemia-induced podocyte apoptosis remain unknown. Recent studies have implicated Src-associated substrate during mitosis of 68 kDa (Sam68) in various cellular processes including RNA metabolism, apoptosis, signal transduction. This study sought to examine the effect of Sam68 on high glucose (HG)-induced podocytes apoptosis, and the mechanism underlying this effect. Immortalized mouse podocytes were exposed to medium containing normal glucose, or HG and Sam68 siRNA, respectively. The expression of Sam68 in podocytes was determined by fluorescence quantitative PCR (qPCR), immunofluorescence and immunoblotting. The role of Sam68 in HG-induced podocyte apoptosis was further evaluated by inhibiting Sam68 expression by Sam68 siRNA and performing flow cytometry. The mRNA and protein expression of pro-apoptosis gene Bax and anti-apoptotic gene Bcl-2 were assessed by qRCR and immunoblotting. In the present study, it was first demonstrated that Sam68 was upregulated in a time and dose-dependent manner in in vitro HG-treated podocytes. Pretreatment with Sam68 siRNA markedly decreased nuclear Sam68 expression. Moreover, the effects of HG-induced apoptosis were also abrogated by Sam68 knockdown in cultured podocytes. Furthermore, HG increased Bax and decreased Bcl-2 protein expression in cultured podocytes, and this effect was blocked by Sam68 knockdown. The results of the present study revealed that Sam68 mediated HG-induced podocyte apoptosis, probably through the Bax/Bcl-2 signaling pathway, and thus may be a potential therapeutic target for DN.
Collapse
Affiliation(s)
- Yuyu Chen
- The Second School of Clinical Medicine, Southern Medical University, Guangzhou, Guangdong 510180, P.R. China
| | - Li Zhang
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangzhou, Guangdong 510080, P.R. China
| | - Shuangxin Liu
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangzhou, Guangdong 510080, P.R. China
| | - Binfeng Yao
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangzhou, Guangdong 510080, P.R. China
| | - Hong Zhang
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangzhou, Guangdong 510080, P.R. China
| | - Shun Liang
- Division of Nephrology, Yue Bei People's Hospital, Shaoguan, Guangdong 512025, P.R. China
| | - Jianchao Ma
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangzhou, Guangdong 510080, P.R. China
| | - Xinling Liang
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangzhou, Guangdong 510080, P.R. China
| | - Wei Shi
- Division of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangzhou, Guangdong 510080, P.R. China
| |
Collapse
|
18
|
Rojas-Canales DM, Li JY, Makuei L, Gleadle JM. Compensatory renal hypertrophy following nephrectomy: When and how? Nephrology (Carlton) 2019; 24:1225-1232. [PMID: 30809888 DOI: 10.1111/nep.13578] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2019] [Indexed: 12/16/2022]
Abstract
Following surgical removal of one kidney, the other enlarges and increases its function. The mechanism for the sensing of this change and the growth is incompletely understood but begins within days and compensatory renal hypertrophy (CRH) is the dominant contributor to the growth. In many individuals undergoing nephrectomy for cancer or kidney donation this produces a substantial and helpful increase in renal function. Two main mechanisms have been proposed, one in which increased activity by the remaining kidney leads to hypertrophy, the second in which there is release of a kidney specific factor in response to a unilateral nephrectomy that initiates CRH. Whilst multiple growth factors and pathways such as the mTORC pathway have been implicated in experimental studies, their roles and the precise mechanism of CRH are not defined. Unrestrained hypoxia inducible factor activation in renal cancer promotes growth and may play an important role in driving CRH.
Collapse
Affiliation(s)
- Darling M Rojas-Canales
- College of Medicine and Public Health and Medicine, Flinders University, Adelaide, South Australia, Australia.,Department of Renal Medicine, Flinders Medical Centre, Adelaide, South Australia, Australia
| | - Jordan Y Li
- College of Medicine and Public Health and Medicine, Flinders University, Adelaide, South Australia, Australia.,Department of Renal Medicine, Flinders Medical Centre, Adelaide, South Australia, Australia
| | - Leek Makuei
- College of Medicine and Public Health and Medicine, Flinders University, Adelaide, South Australia, Australia
| | - Jonathan M Gleadle
- College of Medicine and Public Health and Medicine, Flinders University, Adelaide, South Australia, Australia.,Department of Renal Medicine, Flinders Medical Centre, Adelaide, South Australia, Australia
| |
Collapse
|
19
|
Zhu Y, Li Q, Xun W, Chen Y, Zhang C, Sun S. Blocking P2X7 receptor ameliorates oxidized LDL-mediated podocyte apoptosis. Mol Biol Rep 2019; 46:3809-3816. [DOI: 10.1007/s11033-019-04823-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 04/13/2019] [Indexed: 01/21/2023]
|
20
|
Zha F, Bai L, Tang B, Li J, Wang Y, Zheng P, Ji T, Bai S. MicroRNA-503 contributes to podocyte injury via targeting E2F3 in diabetic nephropathy. J Cell Biochem 2019; 120:12574-12581. [PMID: 30834596 DOI: 10.1002/jcb.28524] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 01/04/2019] [Accepted: 01/14/2019] [Indexed: 12/29/2022]
Abstract
Diabetic nephropathy (DN) is serious diabetic complication with capillary injury. Podocyte injury exerts a crucial effect on DN pathogenesis. MicroRNA-503 (miR-503) has been reported in various diseases including DN. Here, we investigated the detailed mechanism of miR-503 in the podocyte injury of DN. The functional role of miR-503 was investigated in cultured podocytes and diabetic rats. Podocyte injury was evaluated by migration and apoptosis experiments in podocytes and we observed that high glucose elevated miR-503 in a time and dose-dependent manner. Meanwhile, E2F transcription factor 3 (E2F3), as a crucial regulator in multiple diseases, was predicted as a potential target of miR-503 here. It was shown that E2F3 was greatly decreased in podocytes incubated with high glucose and miR-503 modulated its expression negatively. In addition, downregulation of E2F3 contributed to podocyte injury, which was reversed by miR-503 inhibitors in vitro. Furthermore, we proved that increase of miR-503 resulted in an unfavorable renal function in diabetic rats via targeting E2F3. These revealed for the first time that the overexpression of miR-503 promoted podocyte injury via targeting E2F3 in diabetic nephropathy and miR-503/E2F3 axis might represent a pathological mechanism of diabetic nephropathy progression.
Collapse
Affiliation(s)
- Fangfang Zha
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University, Qingpu District, Shanghai, P. R. China
| | - Lin Bai
- Department of Nephrology, Huai'an Second People's Hospital, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Huai'an, P. R. China
| | - Bo Tang
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University, Qingpu District, Shanghai, P. R. China
| | - Ji Li
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University, Qingpu District, Shanghai, P. R. China
| | - Yakun Wang
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University, Qingpu District, Shanghai, P. R. China
| | - PengXi Zheng
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University, Qingpu District, Shanghai, P. R. China
| | - Tingting Ji
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University, Qingpu District, Shanghai, P. R. China
| | - Shoujun Bai
- Department of Nephrology, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University, Qingpu District, Shanghai, P. R. China
| |
Collapse
|
21
|
Meng XM. Inflammatory Mediators and Renal Fibrosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1165:381-406. [PMID: 31399975 DOI: 10.1007/978-981-13-8871-2_18] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Renal inflammation is the initial, healthy response to renal injury. However, prolonged inflammation promotes the fibrosis process, which leads to chronic pathology and eventually end-stage kidney disease. There are two major sources of inflammatory cells: first, bone marrow-derived leukocytes that include neutrophils, macrophages, fibrocytes and mast cells, and second, locally activated kidney cells such as mesangial cells, podocytes, tubular epithelial cells, endothelial cells and fibroblasts. These activated cells produce many profibrotic cytokines and growth factors that cause accumulation and activation of myofibroblasts, and enhance the production of the extracellular matrix. In particular, activated macrophages are key mediators that drive acute inflammation into chronic kidney disease. They produce large amounts of profibrotic factors and modify the microenvironment via a paracrine effect, and they also transdifferentiate to myofibroblasts directly, although the origin of myofibroblasts in the fibrosing kidney remains controversial. Collectively, understanding inflammatory cell functions and mechanisms during renal fibrosis is paramount to improving diagnosis and treatment of chronic kidney disease.
Collapse
Affiliation(s)
- Xiao-Ming Meng
- School of Pharmacy, Anhui Medical University, Hefei, Anhui, China.
| |
Collapse
|
22
|
Knockdown of TLR4 attenuates high glucose-induced podocyte injury via the NALP3/ASC/Caspase-1 signaling pathway. Biomed Pharmacother 2018; 107:1393-1401. [DOI: 10.1016/j.biopha.2018.08.134] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/24/2018] [Accepted: 08/25/2018] [Indexed: 01/20/2023] Open
|
23
|
Zhang H, Liang S, Du Y, Li R, He C, Wang W, Liu S, Ye Z, Liang X, Shi W, Zhang B. Inducible ATF3-NFAT axis aggravates podocyte injury. J Mol Med (Berl) 2017; 96:53-64. [PMID: 29038896 PMCID: PMC5760612 DOI: 10.1007/s00109-017-1601-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 09/12/2017] [Accepted: 10/05/2017] [Indexed: 01/25/2023]
Abstract
Abstract Podocyte injury and loss contribute to proteinuria, glomerulosclerosis, and eventually kidney failure. Activating transcription factor 3 (ATF3) is a stress inducible transcription factor that is transiently expressed following stimulation. However, we show for the first time an induction of ATF3 in podocytes from patients with chronic kidney disease, including minimal change disease, focal segmental glomerulosclerosis, and diabetic nephropathy. The role of ATF3 induction in podocytes under chronic conditions is currently unknown. Compared with the control (C57 or BKS), ATF3 expression was elevated in animal model of proteinuria (LPS-treated C57 mice) and the model of diabetic nephropathy (db/db mice). Similarly, ATF3 was increased in high glucose (HG)-treated, lipopolysaccharide (LPS)-treated, or Ionomycin-treated podocytes in vitro. Overexpression of ATF3 increased podocyte apoptosis and decreased expression of podocin, the cell marker of podocyte; in contrast, ATF3–small interfering RNA knockdown reduced podocyte apoptosis and increased podocin expression. The translocation of ATF3 to the nucleus was increased upon stimulation. ATF3 directly modulates the regulation of NFATc1 gene promoter activity and alters the expression of Wnt6 and Fzd9, direct target genes of NFATc1 signaling. The ATF3 binding site of NFATc1 gene promoter is located at the region 671–775 base pairs upstream of the transcription start site. These results indicate a novel inducible axis of ATF3–NFAT in podocyte injury and loss. Key messages • The stress factor ATF3 is induced in podocytes from proteinuric patients, including diabetes. • ATF3 increased podocyte apoptosis and injury. • ATF3 directly modulates the regulation of NFATc1 gene promoter activity.
Collapse
Affiliation(s)
- Hong Zhang
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China.,Southern Medical University, Guangzhou, 510515, China
| | - Shun Liang
- Department of Nephrology, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, China
| | - Yue Du
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China.,School of Medicine, South China University of Technology, Guangzhou, 510006, China
| | - Ruizhao Li
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China
| | - Chaosheng He
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China
| | - Wenjian Wang
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China
| | - Shuangxin Liu
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China
| | - Zhiming Ye
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China
| | - Xinling Liang
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China
| | - Wei Shi
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China
| | - Bin Zhang
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106# Zhongshan No. 2 Road, Guangzhou, 510080, China. .,Southern Medical University, Guangzhou, 510515, China. .,School of Medicine, South China University of Technology, Guangzhou, 510006, China.
| |
Collapse
|
24
|
Zhang L, Zhang Q, Liu S, Chen Y, Li R, Lin T, Yu C, Zhang H, Huang Z, Zhao X, Tan X, Li Z, Ye Z, Ma J, Zhang B, Wang W, Shi W, Liang X. DNA methyltransferase 1 may be a therapy target for attenuating diabetic nephropathy and podocyte injury. Kidney Int 2017; 92:140-153. [PMID: 28318634 DOI: 10.1016/j.kint.2017.01.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/21/2016] [Accepted: 01/05/2017] [Indexed: 01/19/2023]
Affiliation(s)
- Li Zhang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | | | - Shuangxin Liu
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yuanhan Chen
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Ruizhao Li
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Ting Lin
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Chunping Yu
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Hong Zhang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhongshun Huang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Xinchen Zhao
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Southern Medical University, Guangzhou, China
| | - Xiaofan Tan
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhuo Li
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhiming Ye
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Jianchao Ma
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Bin Zhang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Wenjian Wang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Wei Shi
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
| | - Xinling Liang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
| |
Collapse
|
25
|
Qi W, Keenan HA, Li Q, Ishikado A, Kannt A, Sadowski T, Yorek MA, Wu IH, Lockhart S, Coppey LJ, Pfenninger A, Liew CW, Qiang G, Burkart AM, Hastings S, Pober D, Cahill C, Niewczas MA, Israelsen WJ, Tinsley L, Stillman IE, Amenta PS, Feener EP, Vander Heiden MG, Stanton RC, King GL. Pyruvate kinase M2 activation may protect against the progression of diabetic glomerular pathology and mitochondrial dysfunction. Nat Med 2017; 23:753-762. [PMID: 28436957 DOI: 10.1038/nm.4328] [Citation(s) in RCA: 314] [Impact Index Per Article: 44.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 03/23/2017] [Indexed: 12/12/2022]
Abstract
Diabetic nephropathy (DN) is a major cause of end-stage renal disease, and therapeutic options for preventing its progression are limited. To identify novel therapeutic strategies, we studied protective factors for DN using proteomics on glomeruli from individuals with extreme duration of diabetes (ł50 years) without DN and those with histologic signs of DN. Enzymes in the glycolytic, sorbitol, methylglyoxal and mitochondrial pathways were elevated in individuals without DN. In particular, pyruvate kinase M2 (PKM2) expression and activity were upregulated. Mechanistically, we showed that hyperglycemia and diabetes decreased PKM2 tetramer formation and activity by sulfenylation in mouse glomeruli and cultured podocytes. Pkm-knockdown immortalized mouse podocytes had higher levels of toxic glucose metabolites, mitochondrial dysfunction and apoptosis. Podocyte-specific Pkm2-knockout (KO) mice with diabetes developed worse albuminuria and glomerular pathology. Conversely, we found that pharmacological activation of PKM2 by a small-molecule PKM2 activator, TEPP-46, reversed hyperglycemia-induced elevation in toxic glucose metabolites and mitochondrial dysfunction, partially by increasing glycolytic flux and PGC-1α mRNA in cultured podocytes. In intervention studies using DBA2/J and Nos3 (eNos) KO mouse models of diabetes, TEPP-46 treatment reversed metabolic abnormalities, mitochondrial dysfunction and kidney pathology. Thus, PKM2 activation may protect against DN by increasing glucose metabolic flux, inhibiting the production of toxic glucose metabolites and inducing mitochondrial biogenesis to restore mitochondrial function.
Collapse
Affiliation(s)
- Weier Qi
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Hillary A Keenan
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Qian Li
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Atsushi Ishikado
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Aimo Kannt
- Sanofi-Aventis Deutschland GmbH, Frankfurt am Main, Germany
| | | | - Mark A Yorek
- Veterans Affairs Medical Center, Iowa City, Iowa, USA
| | - I-Hsien Wu
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | | | | | | | - Chong Wee Liew
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Guifen Qiang
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois, USA.,State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College and Beijing Key Laboratory of Drug Target and Screening Research, Beijing, China
| | - Alison M Burkart
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Stephanie Hastings
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - David Pober
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Christopher Cahill
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Monika A Niewczas
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - William J Israelsen
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Liane Tinsley
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Isaac E Stillman
- Beth Israel Deaconess Medical Center, Division of Anatomic Pathology, Boston, Massachusetts, USA
| | - Peter S Amenta
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Edward P Feener
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Matthew G Vander Heiden
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Robert C Stanton
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - George L King
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
26
|
MicroRNA-27a promotes podocyte injury via PPARγ-mediated β-catenin activation in diabetic nephropathy. Cell Death Dis 2017; 8:e2658. [PMID: 28277542 PMCID: PMC5386567 DOI: 10.1038/cddis.2017.74] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 01/05/2017] [Accepted: 02/02/2017] [Indexed: 12/19/2022]
Abstract
Podocyte injury has a pivotal role in the pathogenesis of diabetic nephropathy (DN). MicroRNA-27a (miR-27a), peroxisome proliferator-activated receptor γ (PPARγ) and β-catenin pathways have been involved in the pathogenesis of DN. Herein, we asked whether miR-27a mediates podocyte injury through PPARγ/β-catenin signaling in DN. The functional relevance of miR-27a, PPARγ and β-catenin were investigated in cultured podocytes and glomeruli of diabetic rats and patients using in vitro and in vivo approaches. Podocyte injury was assessed by migration, invasion and apoptosis assay. Biological parameters were analyzed using enzyme-linked immunosorbent assay. We found that high glucose stimulated miR-27a expression, which, by negatively targeting PPARγ, activated β-catenin signaling as evidenced by upregulation of β-catenin target genes, snail1 and α-smooth muscle actin (α-SMA) and downregulation of podocyte-specific markers podocin and synaptopodin. These changes caused podocyte injury as demonstrated by increased podocyte mesenchymal transition, disrupted podocyte architectural integrity and increased podocyte apoptosis. Furthermore, we provide evidence that miR-27a contributed to unfavorable renal function and increased podocyte injury in diabetic rats. Notably, miR-27a exhibited clinical and biological relevance as it was linked to elevated serum creatinine, proteinuria and reduced creatinine clearance rate. In addition, miR-27a upregulation and activation of PPARγ/β-catenin signaling were verified in renal biopsy samples from DN patients. We propose a novel role of the miR-27a/PPARγ/β-catenin axis in fostering the progression toward more deteriorated podocyte injury in DN. Targeting miR-27a could be a potential therapeutic approach for DN.
Collapse
|
27
|
Kim BS, Cho Y, Lee H, Joo DJ, Huh KH, Kim MS, Kim YS. Comparative Proteomic Analysis of Rapamycin Versus Cyclosporine Combination Treatment in Mouse Podocytes. Transplant Proc 2016; 48:1297-301. [PMID: 27320608 DOI: 10.1016/j.transproceed.2016.01.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 01/13/2016] [Accepted: 01/21/2016] [Indexed: 11/18/2022]
Abstract
BACKGROUND The mechanism of podocyte injury observed with the use of rapamycin (RPM) remains unclear. The conversion from calcineurin inhibitors (CNIs) to RPM in kidney transplant recipients has been associated with a higher incidence of proteinuria and renal injury. In this study, we performed proteomic analyses to investigate the alteration of protein expression in mouse podocytes treated with RPM in comparison with CNI/RPM combination. METHODS Immortalized mouse podocytes were treated with 20 nmol/L RPM or 20 nmol/L RPM + 1 μg/mL cyclosporine. Podocyte proteins were separated by 2-dimensional polyacrylamide gel electrophoresis (2DE) and identified by matrix-assisted laser desorption time-of-flight (MALDI-TOF) mass spectrometry and peptide fingerprinting. Selected proteins were analyzed by means of Western blot assay. RESULTS We identified 36 differently expressed proteins after isolated RPM or CNI/RPM combination treatment in cultured mouse podocytes. There are 3 distinct patterns of protein expression: (1) potentiated down- or upregulation of proteins by CNI/RPM treatment compared with isolated RPM treatment (n = 4); (2) partial offset of down-regulation by CNI/RPM in comparison with RPM treatment (n = 25); (3) no difference in down-regulation between RPM and CNI/RPM treatment (n = 5). We found a significant interplay between RPM and CNI on the expression of the selected proteins in mouse podocytes. This might explain the higher incidence of proteinuria by CNI/RPM combination in clinical settings. CONCLUSIONS Further study is required to elucidate the target protein associated with RPM-induced podocyte injury.
Collapse
Affiliation(s)
- B S Kim
- Division of Nephrology, Department of Internal Medicine, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea; The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Y Cho
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - H Lee
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - D J Joo
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Republic of Korea; Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea
| | - K H Huh
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Republic of Korea; Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea
| | - M S Kim
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Republic of Korea; Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea
| | - Y S Kim
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Republic of Korea; Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea.
| |
Collapse
|
28
|
Cdc42 deficiency induces podocyte apoptosis by inhibiting the Nwasp/stress fibers/YAP pathway. Cell Death Dis 2016; 7:e2142. [PMID: 26986510 PMCID: PMC4823952 DOI: 10.1038/cddis.2016.51] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 02/06/2016] [Accepted: 02/15/2016] [Indexed: 02/07/2023]
Abstract
Podocyte apoptosis is a major mechanism that leads to proteinuria in many chronic kidney diseases. However, the concert mechanisms that cause podocyte apoptosis in these kidney diseases are not fully understood. The Rho family of small GTPases has been shown to be required in maintaining podocyte structure and function. Recent studies have indicated that podocyte-specific deletion of Cdc42 in vivo, but not of RhoA or Rac1, leads to congenital nephrotic syndrome and glomerulosclerosis. However, the underlying cellular events in podocyte controlled by Cdc42 remain unclear. Here, we assessed the cellular mechanisms by which Cdc42 regulates podocyte apoptosis. We found that the expression of Cdc42 and its activity were significantly decreased in high glucose-, lipopolysaccharide- or adriamycin-injured podocytes. Reduced Cdc42 expression in vitro and in vivo by small interfering RNA and selective Cdc42 inhibitor ML-141, respectively, caused podocyte apoptosis and proteinuria. Our results further demonstrated that insufficient Cdc42 or Nwasp, its downstream effector, could decrease the mRNA and protein expression of YAP, which had been regarded as an anti-apoptosis protein in podocyte. Moreover, our data indicated that the loss of stress fibers caused by Cdc42/Nwasp deficiency also decreased Yes-associated protein (YAP) mRNA and protein expression, and induced podocyte apoptosis. Podocyte apoptosis induced by Cdc42/Nwasp/stress fiber deficiency was significantly inhibited by overexpressing-active YAP. Thus, the Cdc42/Nwasp/stress fibers/YAP signal pathway may potentially play an important role in regulating podocyte apoptosis. Maintaining necessary Cdc42 would be one potent way to prevent proteinuria kidney diseases.
Collapse
|
29
|
Podocyte directed therapy of nephrotic syndrome-can we bring the inside out? Pediatr Nephrol 2016; 31:393-405. [PMID: 25939817 DOI: 10.1007/s00467-015-3116-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 12/15/2022]
Abstract
Several of the drugs currently used for the treatment of glomerular diseases are prescribed for their immunotherapeutic or anti-inflammatory properties, based on the current understanding that glomerular diseases are mediated by immune responses. In recent years our understanding of podocytic signalling pathways and the crucial role of genetic predispositions in the pathology of glomerular diseases has broadened. Delineation of those signalling pathways supports the hypothesis that several of the medications and immunosuppressive agents used to treat glomerular diseases directly target glomerular podocytes. Several central downstream signalling pathways merge into regulatory pathways of the podocytic actin cytoskeleton and its connection to the slit diaphragm. The slit diaphragm and the cytoskeleton of the foot process represent a functional unit. A breakdown of the cytoskeletal backbone of the foot processes leads to internalization of slit diaphragm molecules, and internalization of slit diaphragm components in turn negatively affects cytoskeletal signalling pathways. Podocytes display a remarkable ability to recover from complete effacement and to re-form interdigitating foot processes and intact slit diaphragms after pharmacological intervention. This ability indicates an active inside-out signalling machinery which stabilizes integrin complex formations and triggers the recycling of slit diaphragm molecules from intracellular compartments to the cell surface. In this review we summarize current evidence from patient studies and model organisms on the direct impact of immunosuppressive and supportive drugs on podocyte signalling pathways. We highlight new therapeutic targets that may open novel opportunities to enhance and stabilize inside-out pathways in podocytes.
Collapse
|
30
|
Podocyte injury in diabetic nephropathy: implications of angiotensin II – dependent activation of TRPC channels. Sci Rep 2015. [DOI: 10.1038/srep17637 order by 1-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
AbstractInjury to podocytes is considered a major contributor to diabetic kidney disease: their loss causes proteinuria and progressive glomerulosclerosis. Podocyte depletion may result from improper calcium handling due to abnormal activation of the calcium permeant TRPC (Transient Receptor Potential Canonical) channels. Angiotensin II (Ang II) levels are found to be elevated in diabetes; furthermore, it was reported that Ang II causes activation of TRPC6 in podocytes. We hypothesized here that Ang II-mediated calcium influx is aggravated in the podocytes under the conditions of type 1 diabetic nephropathy (DN). Diabetes was induced in the Dahl Salt-Sensitive rats by an injection of streptozotocin (STZ-SS). Eleven weeks post treatment was sufficient for the animals to develop hyperglycemia, excessive urination, weight loss, microalbuminuria, nephrinuria and display renal histological lesions typical for patients with DN. Patch-clamp electrophysiology performed on podocytes of the freshly isolated glomeruli showed enhanced basal TRPC channel activity in the STZ-SS rats and increased response to Ang II; total calcium influx triggered by Ang II application was also augmented in podocytes of these rats. Our studies have a strong potential for advancing the understanding of TRPC-mediated effects on podocytopenia in DN initiation.
Collapse
|
31
|
Ilatovskaya DV, Levchenko V, Lowing A, Shuyskiy LS, Palygin O, Staruschenko A. Podocyte injury in diabetic nephropathy: implications of angiotensin II – dependent activation of TRPC channels. Sci Rep 2015. [DOI: 10.1038/srep17637 order by 1-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
AbstractInjury to podocytes is considered a major contributor to diabetic kidney disease: their loss causes proteinuria and progressive glomerulosclerosis. Podocyte depletion may result from improper calcium handling due to abnormal activation of the calcium permeant TRPC (Transient Receptor Potential Canonical) channels. Angiotensin II (Ang II) levels are found to be elevated in diabetes; furthermore, it was reported that Ang II causes activation of TRPC6 in podocytes. We hypothesized here that Ang II-mediated calcium influx is aggravated in the podocytes under the conditions of type 1 diabetic nephropathy (DN). Diabetes was induced in the Dahl Salt-Sensitive rats by an injection of streptozotocin (STZ-SS). Eleven weeks post treatment was sufficient for the animals to develop hyperglycemia, excessive urination, weight loss, microalbuminuria, nephrinuria and display renal histological lesions typical for patients with DN. Patch-clamp electrophysiology performed on podocytes of the freshly isolated glomeruli showed enhanced basal TRPC channel activity in the STZ-SS rats and increased response to Ang II; total calcium influx triggered by Ang II application was also augmented in podocytes of these rats. Our studies have a strong potential for advancing the understanding of TRPC-mediated effects on podocytopenia in DN initiation.
Collapse
|
32
|
Ilatovskaya DV, Levchenko V, Lowing A, Shuyskiy LS, Palygin O, Staruschenko A. Podocyte injury in diabetic nephropathy: implications of angiotensin II – dependent activation of TRPC channels. Sci Rep 2015. [DOI: 10.1038/srep17637 and 1880=1880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
AbstractInjury to podocytes is considered a major contributor to diabetic kidney disease: their loss causes proteinuria and progressive glomerulosclerosis. Podocyte depletion may result from improper calcium handling due to abnormal activation of the calcium permeant TRPC (Transient Receptor Potential Canonical) channels. Angiotensin II (Ang II) levels are found to be elevated in diabetes; furthermore, it was reported that Ang II causes activation of TRPC6 in podocytes. We hypothesized here that Ang II-mediated calcium influx is aggravated in the podocytes under the conditions of type 1 diabetic nephropathy (DN). Diabetes was induced in the Dahl Salt-Sensitive rats by an injection of streptozotocin (STZ-SS). Eleven weeks post treatment was sufficient for the animals to develop hyperglycemia, excessive urination, weight loss, microalbuminuria, nephrinuria and display renal histological lesions typical for patients with DN. Patch-clamp electrophysiology performed on podocytes of the freshly isolated glomeruli showed enhanced basal TRPC channel activity in the STZ-SS rats and increased response to Ang II; total calcium influx triggered by Ang II application was also augmented in podocytes of these rats. Our studies have a strong potential for advancing the understanding of TRPC-mediated effects on podocytopenia in DN initiation.
Collapse
|
33
|
Podocyte injury in diabetic nephropathy: implications of angiotensin II – dependent activation of TRPC channels. Sci Rep 2015. [DOI: 10.1038/srep17637 order by 8029-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
AbstractInjury to podocytes is considered a major contributor to diabetic kidney disease: their loss causes proteinuria and progressive glomerulosclerosis. Podocyte depletion may result from improper calcium handling due to abnormal activation of the calcium permeant TRPC (Transient Receptor Potential Canonical) channels. Angiotensin II (Ang II) levels are found to be elevated in diabetes; furthermore, it was reported that Ang II causes activation of TRPC6 in podocytes. We hypothesized here that Ang II-mediated calcium influx is aggravated in the podocytes under the conditions of type 1 diabetic nephropathy (DN). Diabetes was induced in the Dahl Salt-Sensitive rats by an injection of streptozotocin (STZ-SS). Eleven weeks post treatment was sufficient for the animals to develop hyperglycemia, excessive urination, weight loss, microalbuminuria, nephrinuria and display renal histological lesions typical for patients with DN. Patch-clamp electrophysiology performed on podocytes of the freshly isolated glomeruli showed enhanced basal TRPC channel activity in the STZ-SS rats and increased response to Ang II; total calcium influx triggered by Ang II application was also augmented in podocytes of these rats. Our studies have a strong potential for advancing the understanding of TRPC-mediated effects on podocytopenia in DN initiation.
Collapse
|
34
|
Ilatovskaya DV, Levchenko V, Lowing A, Shuyskiy LS, Palygin O, Staruschenko A. Podocyte injury in diabetic nephropathy: implications of angiotensin II-dependent activation of TRPC channels. Sci Rep 2015; 5:17637. [PMID: 26656101 PMCID: PMC4674698 DOI: 10.1038/srep17637] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 11/03/2015] [Indexed: 01/05/2023] Open
Abstract
Injury to podocytes is considered a major contributor to diabetic kidney disease: their loss causes proteinuria and progressive glomerulosclerosis. Podocyte depletion may result from improper calcium handling due to abnormal activation of the calcium permeant TRPC (Transient Receptor Potential Canonical) channels. Angiotensin II (Ang II) levels are found to be elevated in diabetes; furthermore, it was reported that Ang II causes activation of TRPC6 in podocytes. We hypothesized here that Ang II-mediated calcium influx is aggravated in the podocytes under the conditions of type 1 diabetic nephropathy (DN). Diabetes was induced in the Dahl Salt-Sensitive rats by an injection of streptozotocin (STZ-SS). Eleven weeks post treatment was sufficient for the animals to develop hyperglycemia, excessive urination, weight loss, microalbuminuria, nephrinuria and display renal histological lesions typical for patients with DN. Patch-clamp electrophysiology performed on podocytes of the freshly isolated glomeruli showed enhanced basal TRPC channel activity in the STZ-SS rats, and increased response to Ang II; total calcium influx triggered by Ang II application was also augmented in podocytes of these rats. Our studies have a strong potential for advancing the understanding of TRPC-mediated effects on podocytopenia in DN initiation.
Collapse
Affiliation(s)
- Daria V Ilatovskaya
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - Vladislav Levchenko
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - Andrea Lowing
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - Leonid S Shuyskiy
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.,Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russian Federation
| | - Oleg Palygin
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - Alexander Staruschenko
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| |
Collapse
|
35
|
Ilatovskaya DV, Levchenko V, Lowing A, Shuyskiy LS, Palygin O, Staruschenko A. Podocyte injury in diabetic nephropathy: implications of angiotensin II – dependent activation of TRPC channels. Sci Rep 2015. [DOI: 10.1038/srep17637 order by 8029-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
AbstractInjury to podocytes is considered a major contributor to diabetic kidney disease: their loss causes proteinuria and progressive glomerulosclerosis. Podocyte depletion may result from improper calcium handling due to abnormal activation of the calcium permeant TRPC (Transient Receptor Potential Canonical) channels. Angiotensin II (Ang II) levels are found to be elevated in diabetes; furthermore, it was reported that Ang II causes activation of TRPC6 in podocytes. We hypothesized here that Ang II-mediated calcium influx is aggravated in the podocytes under the conditions of type 1 diabetic nephropathy (DN). Diabetes was induced in the Dahl Salt-Sensitive rats by an injection of streptozotocin (STZ-SS). Eleven weeks post treatment was sufficient for the animals to develop hyperglycemia, excessive urination, weight loss, microalbuminuria, nephrinuria and display renal histological lesions typical for patients with DN. Patch-clamp electrophysiology performed on podocytes of the freshly isolated glomeruli showed enhanced basal TRPC channel activity in the STZ-SS rats and increased response to Ang II; total calcium influx triggered by Ang II application was also augmented in podocytes of these rats. Our studies have a strong potential for advancing the understanding of TRPC-mediated effects on podocytopenia in DN initiation.
Collapse
|
36
|
Podocyte injury in diabetic nephropathy: implications of angiotensin II – dependent activation of TRPC channels. Sci Rep 2015. [DOI: 10.1038/srep17637 order by 8029-- awyx] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
AbstractInjury to podocytes is considered a major contributor to diabetic kidney disease: their loss causes proteinuria and progressive glomerulosclerosis. Podocyte depletion may result from improper calcium handling due to abnormal activation of the calcium permeant TRPC (Transient Receptor Potential Canonical) channels. Angiotensin II (Ang II) levels are found to be elevated in diabetes; furthermore, it was reported that Ang II causes activation of TRPC6 in podocytes. We hypothesized here that Ang II-mediated calcium influx is aggravated in the podocytes under the conditions of type 1 diabetic nephropathy (DN). Diabetes was induced in the Dahl Salt-Sensitive rats by an injection of streptozotocin (STZ-SS). Eleven weeks post treatment was sufficient for the animals to develop hyperglycemia, excessive urination, weight loss, microalbuminuria, nephrinuria and display renal histological lesions typical for patients with DN. Patch-clamp electrophysiology performed on podocytes of the freshly isolated glomeruli showed enhanced basal TRPC channel activity in the STZ-SS rats and increased response to Ang II; total calcium influx triggered by Ang II application was also augmented in podocytes of these rats. Our studies have a strong potential for advancing the understanding of TRPC-mediated effects on podocytopenia in DN initiation.
Collapse
|
37
|
Ilatovskaya DV, Levchenko V, Lowing A, Shuyskiy LS, Palygin O, Staruschenko A. Podocyte injury in diabetic nephropathy: implications of angiotensin II – dependent activation of TRPC channels. Sci Rep 2015. [DOI: 10.1038/srep17637 order by 1-- gadu] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
AbstractInjury to podocytes is considered a major contributor to diabetic kidney disease: their loss causes proteinuria and progressive glomerulosclerosis. Podocyte depletion may result from improper calcium handling due to abnormal activation of the calcium permeant TRPC (Transient Receptor Potential Canonical) channels. Angiotensin II (Ang II) levels are found to be elevated in diabetes; furthermore, it was reported that Ang II causes activation of TRPC6 in podocytes. We hypothesized here that Ang II-mediated calcium influx is aggravated in the podocytes under the conditions of type 1 diabetic nephropathy (DN). Diabetes was induced in the Dahl Salt-Sensitive rats by an injection of streptozotocin (STZ-SS). Eleven weeks post treatment was sufficient for the animals to develop hyperglycemia, excessive urination, weight loss, microalbuminuria, nephrinuria and display renal histological lesions typical for patients with DN. Patch-clamp electrophysiology performed on podocytes of the freshly isolated glomeruli showed enhanced basal TRPC channel activity in the STZ-SS rats and increased response to Ang II; total calcium influx triggered by Ang II application was also augmented in podocytes of these rats. Our studies have a strong potential for advancing the understanding of TRPC-mediated effects on podocytopenia in DN initiation.
Collapse
|
38
|
Visweswaran GRR, Gholizadeh S, Ruiters MHJ, Molema G, Kok RJ, Kamps JAAM. Targeting Rapamycin to Podocytes Using a Vascular Cell Adhesion Molecule-1 (VCAM-1)-Harnessed SAINT-Based Lipid Carrier System. PLoS One 2015; 10:e0138870. [PMID: 26407295 PMCID: PMC4583306 DOI: 10.1371/journal.pone.0138870] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 09/04/2015] [Indexed: 11/24/2022] Open
Abstract
Together with mesangial cells, glomerular endothelial cells and the basement membrane, podocytes constitute the glomerular filtration barrier (GFB) of the kidney. Podocytes play a pivotal role in the progression of various kidney-related diseases such as glomerular sclerosis and glomerulonephritis that finally lead to chronic end-stage renal disease. During podocytopathies, the slit-diaphragm connecting the adjacent podocytes are detached leading to severe loss of proteins in the urine. The pathophysiology of podocytopathies makes podocytes a potential and challenging target for nanomedicine development, though there is a lack of known molecular targets for cell selective drug delivery. To identify VCAM-1 as a cell-surface receptor that is suitable for binding and internalization of nanomedicine carrier systems by podocytes, we investigated its expression in the immortalized podocyte cell lines AB8/13 and MPC-5, and in primary podocytes. Gene and protein expression analyses revealed that VCAM-1 expression is increased by podocytes upon TNFα-activation for up to 24 h. This was paralleled by anti-VCAM-1 antibody binding to the TNFα-activated cells, which can be employed as a ligand to facilitate the uptake of nanocarriers under inflammatory conditions. Hence, we next explored the possibilities of using VCAM-1 as a cell-surface receptor to deliver the potent immunosuppressant rapamycin to TNFα-activated podocytes using the lipid-based nanocarrier system Saint-O-Somes. Anti-VCAM-1-rapamycin-SAINT-O-Somes more effectively inhibited the cell migration of AB8/13 cells than free rapamycin and non-targeted rapamycin-SAINT-O-Somes indicating the potential of VCAM-1 targeted drug delivery to podocytes.
Collapse
Affiliation(s)
- Ganesh Ram R. Visweswaran
- Department of Pathology & Medical Biology, Medical Biology Section, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Shima Gholizadeh
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, the Netherlands
| | - Marcel H. J. Ruiters
- Department of Pathology & Medical Biology, Medical Biology Section, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Grietje Molema
- Department of Pathology & Medical Biology, Medical Biology Section, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Robbert J. Kok
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, the Netherlands
| | - Jan. A. A. M. Kamps
- Department of Pathology & Medical Biology, Medical Biology Section, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- * E-mail:
| |
Collapse
|
39
|
Mami I, Bouvier N, El Karoui K, Gallazzini M, Rabant M, Laurent-Puig P, Li S, Tharaux PL, Beaune P, Thervet E, Chevet E, Hu GF, Pallet N. Angiogenin Mediates Cell-Autonomous Translational Control under Endoplasmic Reticulum Stress and Attenuates Kidney Injury. J Am Soc Nephrol 2015. [PMID: 26195817 DOI: 10.1681/asn.2015020196] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Endoplasmic reticulum (ER) stress is involved in the pathophysiology of kidney disease and aging, but the molecular bases underlying the biologic outcomes on the evolution of renal disease remain mostly unknown. Angiogenin (ANG) is a ribonuclease that promotes cellular adaptation under stress but its contribution to ER stress signaling remains elusive. In this study, we investigated the ANG-mediated contribution to the signaling and biologic outcomes of ER stress in kidney injury. ANG expression was significantly higher in samples from injured human kidneys than in samples from normal human kidneys, and in mouse and rat kidneys, ANG expression was specifically induced under ER stress. In human renal epithelial cells, ER stress induced ANG expression in a manner dependent on the activity of transcription factor XBP1, and ANG promoted cellular adaptation to ER stress through induction of stress granules and inhibition of translation. Moreover, the severity of renal lesions induced by ER stress was dramatically greater in ANG knockout mice (Ang(-/-)) mice than in wild-type mice. These results indicate that ANG is a critical mediator of tissue adaptation to kidney injury and reveal a physiologically relevant ER stress-mediated adaptive translational control mechanism.
Collapse
Affiliation(s)
- Iadh Mami
- Institut National de la Sante et de la Recherche Médicale (INSERM) U1147, Saints-Pères Research Center Paris, France; Paris Descartes University Paris, France
| | | | - Khalil El Karoui
- Paris Descartes University Paris, France; INSERM U1151, Sick Childrens Necker Institute Paris, France
| | - Morgan Gallazzini
- Paris Descartes University Paris, France; INSERM U1151, Sick Childrens Necker Institute Paris, France
| | - Marion Rabant
- Paris Descartes University Paris, France; Pathology Department, Necker Hospital Paris, France
| | - Pierre Laurent-Puig
- Institut National de la Sante et de la Recherche Médicale (INSERM) U1147, Saints-Pères Research Center Paris, France; Paris Descartes University Paris, France; Clinical Chemistry and
| | - Shuping Li
- Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts
| | | | - Philippe Beaune
- Institut National de la Sante et de la Recherche Médicale (INSERM) U1147, Saints-Pères Research Center Paris, France; Paris Descartes University Paris, France; Clinical Chemistry and
| | - Eric Thervet
- Paris Descartes University Paris, France; Nephrology Departments, Georges Pompidou European Hospital Paris, France
| | - Eric Chevet
- INSERM, UMR-U1053, Team Endoplasmic Reticulum Stress and Cancer, Bordeaux, France
| | - Guo-Fu Hu
- Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts
| | - Nicolas Pallet
- Institut National de la Sante et de la Recherche Médicale (INSERM) U1147, Saints-Pères Research Center Paris, France; Paris Descartes University Paris, France; Clinical Chemistry and Nephrology Departments, Georges Pompidou European Hospital Paris, France;
| |
Collapse
|
40
|
Yoo TH, Fornoni A. Nonimmunologic targets of immunosuppressive agents in podocytes. Kidney Res Clin Pract 2015; 34:69-75. [PMID: 26484025 PMCID: PMC4570600 DOI: 10.1016/j.krcp.2015.03.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 03/16/2015] [Accepted: 03/21/2015] [Indexed: 02/06/2023] Open
Abstract
Proteinuria is a characteristic finding in glomerular diseases and is closely associated with renal outcomes. In addition, therapeutic interventions that reduce proteinuria improve renal prognosis. Accumulating evidence has demonstrated that podocytes act as key modulators of glomerular injury and proteinuria. The podocyte, or glomerular visceral epithelial cell, is a highly specialized and differentiated cell that forms interdigitated foot processes with neighboring podocytes, which are bridged together by an extracellular structure known as the "slit diaphragm" (SD). The SD acts as a size- and charge-selective barrier to plasma protein. Derangement of SD structure or loss of SD-associated protein results in podocyte injury and proteinuria. During the past decades, several immune-modulating agents have been used for the treatment of glomerular diseases and for the reduction of proteinuria. Interestingly, recent studies have demonstrated that immunosuppressive agents can have a direct effect on the SD-associated proteins and stabilize actin cytoskeleton in podocyte and have therefore introduced the concept of nonimmunologic mechanism of renoprotection by immunomodulators. This review focuses on the evidence that immuno-modulating agents directly target podocytes.
Collapse
Affiliation(s)
- Tae-Hyun Yoo
- Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea
- Division of Nephrology and Hypertension, Department of Medicine, Leonard M. Miller School of Medicine, University of Miami, Miami, FL, USA
- Peggy and Harold Katz Family Drug Discovery Center, Leonard M. Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Alessia Fornoni
- Division of Nephrology and Hypertension, Department of Medicine, Leonard M. Miller School of Medicine, University of Miami, Miami, FL, USA
- Peggy and Harold Katz Family Drug Discovery Center, Leonard M. Miller School of Medicine, University of Miami, Miami, FL, USA
| |
Collapse
|
41
|
Abstract
Focal segmental glomerulosclerosis (FSGS) describes both a common lesion in progressive kidney disease, and a disease characterized by marked proteinuria and podocyte injury. The initial injuries vary widely. Monogenetic forms of FSGS are largely due to alterations in structural genes of the podocyte, many of which result in early onset of disease. Genetic risk alleles in apolipoprotein L1 are especially prevalent in African Americans, and are linked not only to adult-onset FSGS but also to progression of some other kidney diseases. The recurrence of FSGS in some transplant recipients whose end-stage renal disease was caused by FSGS points to circulating factors in disease pathogenesis, which remain incompletely understood. In addition, infection, drug use, and secondary maladaptive responses after loss of nephrons from any cause may also cause FSGS. Varying phenotypes of the sclerosis are also manifest, with varying prognosis. The so-called tip lesion has the best prognosis, whereas the collapsing type of FSGS has the worst prognosis. New insights into glomerular cell injury response and repair may pave the way for possible therapeutic strategies.
Collapse
|
42
|
Zhang L, Li R, Shi W, Liang X, Liu S, Ye Z, Yu C, Chen Y, Zhang B, Wang W, Lai Y, Ma J, Li Z, Tan X. NFAT2 inhibitor ameliorates diabetic nephropathy and podocyte injury in db/db mice. Br J Pharmacol 2014; 170:426-39. [PMID: 23826864 DOI: 10.1111/bph.12292] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 06/18/2013] [Accepted: 06/21/2013] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND AND PURPOSE Podocyte injury plays a key role in the development of diabetic nephropathy (DN). We have recently shown that 11R-VIVIT, an inhibitor of cell-permeable nuclear factor of activated T-cells (NFAT), attenuates podocyte apoptosis induced by high glucose in vitro. However, it is not known whether 11R-VIVIT has a protective effect on DN, especially podocyte injury, under in vivo diabetic conditions. Hence, we examined the renoprotective effects of 11R-VIVIT in diabetic db/db mice and the possible mechanisms underlying its protective effects on podocyte injury in vivo and in vitro. EXPERIMENTAL APPROACH Type 2 diabetic db/db mice received i.p. injections of 11R-VIVIT (1 mg·kg(-1)) three times a week and were killed after 8 weeks. Immortalized mouse podocytes were cultured under different experimental conditions. KEY RESULTS 11R-VIVIT treatment markedly attenuated the albuminuria in diabetic db/db mice and also alleviated mesangial matrix expansion and podocyte injury. However, body weight, food and water intake, and glucose levels were unaffected. It also attenuated the increased NFAT2 activation and enhanced urokinase-type plasminogen activator receptor (uPA receptor) expression in glomerulor podocytes. In cultured podocytes, the increased nuclear accumulation of NFAT2 and uPA receptor expression induced by high glucose treatment was prevented by 11R-VIVIT or NFAT2-knockdown; this was accompanied by improvements in the filtration barrier function of the podocyte monolayer. CONCLUSIONS AND IMPLICATIONS The NFAT inhibitor 11R-VIVIT might be a useful therapeutic strategy for protecting podocytes and treating DN. The calcinerin/NFAT2/uPA receptor signalling pathway should be exploited as a therapeutic target for protecting podocytes from injury in DN.
Collapse
Affiliation(s)
- Li Zhang
- Southern Medical University, Guangzhou, China; Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
ELISA analysis of urinary nephrin and podocalyxin standardized by aquaporin-2 in adult patients with nephrotic syndrome. J Nephrol 2014; 27:411-7. [PMID: 24737246 DOI: 10.1007/s40620-014-0066-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 12/31/2013] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To investigate urinary nephrin and podocalyxin standardized by aquaporin (AQP)-2 using the enzyme-linked immunosorbent assay (ELISA) method in adult nephrotic syndrome (NS) patients. METHODS In 107 adult NS patients (27 proliferative nephritis, 77 non-proliferative, and 3 amyloidosis) undergoing renal biopsy, urinary nephrin, podocalyxin and AQP2 were measured by ELISA. Urinary nephrin and podocalyxin were standardized by AQP2 (neph/AQP and PCX/AQP) and values were compared with 11 healthy controls. RESULTS Urinary neph/AQP correlated positively to PCX/AQP (r = 0.51, p < 0.001). Urinary neph/AQP and PCX/AQP were lower in controls than NS patients. Both proliferative and non-proliferative NS patients excreted high urinary neph/AQP and PCX/AQP without a significant difference between them (p > 0.05). Patients with focal segmental glomerular sclerosis (FSGS) excreted higher urinary neph/AQP (p = 0.09) and PCX/AQP (p < 0.05) compared to the other patients. Urinary neph/AQP and PCX/AQP were increased in the immunoglobulin M nephropathy patients. Amyloidosis patients excreted lower neph/AQP and PCX/AQP. The sensitivity was 0.87 and specificity 0.37 when the neph/AQP borderline value of 0.16 was adopted [area under the curve (AUC) = 0.61]. The sensitivity was 0.74 and specificity 0.61 when the PCX/AQP borderline value was 3.06 (AUC = 0.69). CONCLUSIONS Urinary neph/AQP and PCX/AQP are increased in NS patients, with FSGS patients showing the highest levels. To distinguish FSGS from other NS forms, the measurement of urinary PCX/AQP may be a practical method, and superior to neph/AQP.
Collapse
|
44
|
Towler DA. Mitochondrial ROS deficiency and diabetic complications: AMP[K]-lifying the adaptation to hyperglycemia. J Clin Invest 2013; 123:4573-6. [PMID: 24135143 DOI: 10.1172/jci72326] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Global, sustained production of ROS has deleterious effects on tissue structure and function and gives rise to biochemical and physiological changes associated with organ senescence. Specific, localized ROS metabolites generated by mitochondria and NADPH oxidases also transduce homeostatic information in response to metabolic, mechanical, and inflammatory cues. In this issue of the JCI, Dugan and colleagues demonstrate that mitochondrial-derived ROS, which is maintained by a feed-forward AMP kinase activation cascade, is reduced in diabetes and plays an adaptive role in preserving renal glomerular function during hyperglycemia. This enlightened view of mitochondrial ROS biology forces us to reconsider therapeutic approaches to metabolic disease complications such as diabetic nephropathy.
Collapse
|
45
|
Zhang J, Pippin JW, Krofft RD, Naito S, Liu ZH, Shankland SJ. Podocyte repopulation by renal progenitor cells following glucocorticoids treatment in experimental FSGS. Am J Physiol Renal Physiol 2013; 304:F1375-89. [PMID: 23486009 DOI: 10.1152/ajprenal.00020.2013] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Prednisone is a mainstay of treatment for patients with focal segmental glomerulosclerosis (FSGS), a disease characterized by reduced podocyte number and glomerulosclerosis. Although the systemic immune-modulatory effects of prednisone are well-known, direct tissue effects on glomerular cells are poorly understood. Experimental FSGS was induced in mice with a cytotoxic anti-podocyte antibody, resulting in an abrupt decrease in podocyte number by day 3, proteinuria, and the development of glomerulosclerosis. Administering daily prednisone to mice with FSGS, beginning at day 3, significantly increased podocyte number at weeks 2 and 4. Podocyte number did not increase in control mice with FSGS given DMSO. The increase in podocyte number in prednisone-treated mice correlated significantly with reduced glomerulosclerosis. Prednisone reduced podocyte apoptosis measured by synaptopodin⁺/caspase-3⁺ double staining. Additionally, the number of podocyte progenitors, defined as cells expressing both a parietal epithelial cell protein and a podocyte protein, was significantly increased in prednisone-treated mice with FSGS at weeks 2 and 4. This was associated with increased phospho-ERK staining in both parietal epithelial cells (PAX2⁺/p-ERK⁺) and in podocyte progenitors (WT-1⁺/p-ERK⁺ lining Bowman's capsule). These data show that in this model of experimental FSGS, prednisone augments glomerular repair by increasing podocyte number through direct effects on both glomerular epithelial cells. Prednisone limits podocyte loss by reducing apoptosis, and it increases regeneration by augmenting the number of podocyte progenitors. The data support a direct glomerular cell action for prednisone in improving outcomes in FSGS.
Collapse
Affiliation(s)
- Jiong Zhang
- Division of Nephrology, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | | | | | | | | | | |
Collapse
|
46
|
Fiorentino L, Cavalera M, Menini S, Marchetti V, Mavilio M, Fabrizi M, Conserva F, Casagrande V, Menghini R, Pontrelli P, Arisi I, D'Onofrio M, Lauro D, Khokha R, Accili D, Pugliese G, Gesualdo L, Lauro R, Federici M. Loss of TIMP3 underlies diabetic nephropathy via FoxO1/STAT1 interplay. EMBO Mol Med 2013; 5:441-55. [PMID: 23401241 PMCID: PMC3598083 DOI: 10.1002/emmm.201201475] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 12/10/2012] [Accepted: 12/11/2012] [Indexed: 01/15/2023] Open
Abstract
ADAM17 and its inhibitor TIMP3 are involved in nephropathy, but their role in diabetic kidney disease (DKD) is unclear. Diabetic Timp3−/− mice showed increased albuminuria, increased membrane thickness and mesangial expansion. Microarray profiling uncovered a significant reduction of Foxo1 expression in diabetic Timp3−/− mice compared to WT, along with FoxO1 target genes involved in autophagy, while STAT1, a repressor of FoxO1 transcription, was increased. Re-expression of Timp3 in Timp3−/− mesangial cells rescued the expression of Foxo1 and its targets, and decreased STAT1 expression to control levels; abolishing STAT1 expression led to a rescue of FoxO1, evoking a role of STAT1 in linking Timp3 deficiency to FoxO1. Studies on kidney biopsies from patients with diabetic nephropathy confirmed a significant reduction in TIMP3, FoxO1 and FoxO1 target genes involved in autophagy compared to controls, while STAT1 expression was strongly increased. Our study suggests that loss of TIMP3 is a hallmark of DKD in human and mouse models and designates TIMP3 as a new possible therapeutic target for diabetic nephropathy.
Collapse
|
47
|
Li R, Zhang L, Shi W, Zhang B, Liang X, Liu S, Wang W. NFAT2 mediates high glucose-induced glomerular podocyte apoptosis through increased Bax expression. Exp Cell Res 2013; 319:992-1000. [PMID: 23340267 DOI: 10.1016/j.yexcr.2013.01.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Revised: 12/25/2012] [Accepted: 01/07/2013] [Indexed: 01/19/2023]
Abstract
BACKGROUND Hyperglycemia promotes podocyte apoptosis and plays a key role in the pathogenesis of diabetic nephropathy. However, the mechanisms that mediate hyperglycemia-induced podocyte apoptosis is still far from being fully understood. Recent studies reported that high glucose activate nuclear factor of activated T cells (NFAT) in vascular smooth muscle or pancreatic β-cells. Here, we sought to determine if hyperglycemia activates NFAT2 in cultured podocyte and whether this leads to podocyte apoptosis. Meanwhile, we also further explore the mechanisms of NFAT2 activation and NFAT2 mediates high glucose-induced podocyte apoptosis. METHODS Immortalized mouse podocytes were cultured in media containing normal glucose (NG), or high glucose (HG) or HG plus cyclosporine A (a pharmacological inhibitor of calcinerin) or 11R-VIVIT (a special inhibitor of NFAT2). The activation of NFAT2 in podocytes was detected by western blotting and immunofluorescence assay. The role of NFAT2 in hyperglycemia-induced podocyte apoptosis was further evaluated by observing the inhibition of NFAT2 activation by 11R-VIVIT using flow cytometer. Intracellular Ca(2+) was monitored in HG-treated podcocytes using Fluo-3/AM. The mRNA and protein expression of apoptosis gene Bax were measured by real time-qPCR and western blotting. RESULTS HG stimulation activated NFAT2 in a time- and dose-dependent manner in cultured podocytes. Pretreatment with cyclosporine A (500nM) or 11R-VIVIT (100nM) completely blocked NFAT2 nuclear accumulation. Meanwhile, the apoptosis effects induced by HG were also abrogated by concomitant treatment with 11R-VIVIT in cultured podocytes. We further found that HG also increased [Ca(2+)]i, leading to activation of calcineurin, and subsequent increased nuclear accumulation of NFAT2 and Bax expression in cultured podocytes. CONCLUSION Our results identify a new finding that HG-induced podocyte apoptosis is mediated by calcineurin/NFAT2/Bax signaling pathway, which may present a promising target for therapeutic intervention.
Collapse
Affiliation(s)
- Ruizhao Li
- Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan No. 2 Road, Guangzhou 510080, People's Republic of China.
| | | | | | | | | | | | | |
Collapse
|
48
|
Vashistha H, Singhal PC, Malhotra A, Husain M, Mathieson P, Saleem MA, Kuriakose C, Seshan S, Wilk A, Delvalle L, Peruzzi F, Giorgio M, Pelicci PG, Smithies O, Kim HS, Kakoki M, Reiss K, Meggs LG. Null mutations at the p66 and bradykinin 2 receptor loci induce divergent phenotypes in the diabetic kidney. Am J Physiol Renal Physiol 2012; 303:F1629-40. [PMID: 23019230 PMCID: PMC3532473 DOI: 10.1152/ajprenal.00246.2012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 09/25/2012] [Indexed: 12/28/2022] Open
Abstract
Candidate genes have been identified that confer increased risk for diabetic glomerulosclerosis (DG). Mice heterozygous for the Akita (Ins2(+/C96Y)) diabetogenic mutation with a second mutation introduced at the bradykinin 2 receptor (B2R(-/-)) locus express a disease phenotype that approximates human DG. Src homology 2 domain transforming protein 1 (p66) controls mitochondrial metabolism and cellular responses to oxidative stress, aging, and apoptosis. We generated p66-null Akita mice to test whether inactivating mutations at the p66 locus will rescue kidneys of Akita mice from disease-causing mutations at the Ins2 and B2R loci. Here we show null mutations at the p66 and B2R loci interact with the Akita (Ins2(+/C96Y)) mutation, independently and in combination, inducing divergent phenotypes in the kidney. The B2R(-/-) mutation induces detrimental phenotypes, as judged by increased systemic and renal levels of oxidative stress, histology, and urine albumin excretion, whereas the p66-null mutation confers a powerful protection phenotype. To elucidate the mechanism(s) of the protection phenotype, we turned to our in vitro system. Experiments with cultured podocytes revealed previously unrecognized cross talk between p66 and the redox-sensitive transcription factor p53 that controls hyperglycemia-induced ROS metabolism, transcription of p53 target genes (angiotensinogen, angiotensin II type-1 receptor, and bax), angiotensin II generation, and apoptosis. RNA-interference targeting p66 inhibits all of the above. Finally, protein levels of p53 target genes were upregulated in kidneys of Akita mice but unchanged in p66-null Akita mice. Taken together, p66 is a potential molecular target for therapeutic intervention in DG.
Collapse
Affiliation(s)
- Himanshu Vashistha
- Institute for Translational Research, Nephrology Research Laboratory, Ochsner Health Foundation, Dept. of Nephrology, New Orleans, LA 70121, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
McMahon GM, Datta D, Bruneau S, Kann M, Khalid M, Ho J, Seto T, Kreidberg JA, Stillman IE, Briscoe DM. Constitutive activation of the mTOR signaling pathway within the normal glomerulus. Biochem Biophys Res Commun 2012; 425:244-9. [PMID: 22828505 DOI: 10.1016/j.bbrc.2012.07.075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 07/15/2012] [Indexed: 02/06/2023]
Abstract
Agents that target the activity of the mammalian target of rapamycin (mTOR) kinase in humans are associated with proteinuria. However, the mechanisms underlying mTOR activity and signaling within the kidney are poorly understood. In this study, we developed a sensitive immunofluorescence technique for the evaluation of activated pmTOR and its associated signals in situ. While we find that pmTOR is rarely expressed in normal non-renal tissues, we consistently find intense expression in glomeruli within normal mouse and human kidneys. Using double staining, we find that the expression of pmTOR co-localizes with nephrin in podocytes and expression appears minimal within other cell types in the glomerulus. In addition, we found that pmTOR was expressed on occasional renal tubular cells within mouse and human kidney specimens. We also evaluated mTOR signaling in magnetic bead-isolated glomeruli from normal mice and, by Western blot analysis, we confirmed function of the pathway in glomerular cells vs. interstitial cells. Furthermore, we found that the activity of the pathway as well as the expression of VEGF, a target of mTOR-induced signaling, were reduced within glomeruli of mice following treatment with rapamycin. Collectively, these findings demonstrate that the mTOR signaling pathway is constitutively hyperactive within podocytes. We suggest that pmTOR signaling functions to regulate glomerular homeostasis in part via the inducible expression of VEGF.
Collapse
Affiliation(s)
- Gearoid M McMahon
- The Transplantation Research Center, Division of Nephrology, Department of Medicine, Children's Hospital, and The Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Flaquer M, Franquesa M, Vidal A, Bolaños N, Torras J, Lloberas N, Herrero-Fresneda I, Grinyó JM, Cruzado JM. Hepatocyte growth factor gene therapy enhances infiltration of macrophages and may induce kidney repair in db/db mice as a model of diabetes. Diabetologia 2012; 55:2059-68. [PMID: 22460762 PMCID: PMC3369134 DOI: 10.1007/s00125-012-2535-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 02/20/2012] [Indexed: 11/03/2022]
Abstract
AIMS/HYPOTHESIS We previously demonstrated hepatocyte growth factor (HGF) gene therapy was able to induce regression of glomerulosclerosis in diabetic nephropathy through local reparative mechanisms. The aim of this study was to test whether bone-marrow-derived cells are also involved in this HGF-induced reparative process. METHODS We have created chimeric db/db mice as a model of diabetes that produce enhanced green fluorescent protein (EGFP) in bone marrow cells. We performed treatment with HGF gene therapy either alone or in combination with granulocyte-colony stimulating factor, in order to induce mobilisation of haematopoietic stem cells in these diabetic and chimeric animals. RESULTS We find HGF gene therapy enhances renal expression of stromal-cell-derived factor-1 and is subsequently associated with an increased number of bone-marrow-derived cells getting into the injured kidneys. These cells are mainly monocyte-derived macrophages, which may contribute to the renal tissue repair and regeneration consistently observed in our model. Finally, HGF gene therapy is associated with the presence of a small number of Bowman's capsule parietal epithelial cells producing EGFP, suggesting they are fused with bone-marrow-derived cells and are contributing to podocyte repopulation. CONCLUSIONS/INTERPRETATION Altogether, our findings provide new evidence about the therapeutic role of HGF and open new opportunities for inducing renal regeneration in diabetic nephropathy.
Collapse
Affiliation(s)
- M. Flaquer
- Nephrology Laboratory, Departament de Ciències Clíniques, IDIBELL, University of Barcelona, Bellvitge Hospital, Barcelona, Spain
| | - M. Franquesa
- Nephrology Laboratory, Departament de Ciències Clíniques, IDIBELL, University of Barcelona, Bellvitge Hospital, Barcelona, Spain
| | - A. Vidal
- Pathology Service, IDIBELL, Bellvitge Hospital, University of Barcelona, Barcelona, Spain
| | - N. Bolaños
- Nephrology Laboratory, Departament de Ciències Clíniques, IDIBELL, University of Barcelona, Bellvitge Hospital, Barcelona, Spain
| | - J. Torras
- Nephrology Laboratory, Departament de Ciències Clíniques, IDIBELL, University of Barcelona, Bellvitge Hospital, Barcelona, Spain
- Servei de Nefrologia, Department of Nephrology, Hospital Universitari de Bellvitge, University of Barcelona, IDIBELL, Feixa Llarga s/n, L’Hospitalet de Llobregat, 08907 Barcelona, Spain
| | - N. Lloberas
- Nephrology Laboratory, Departament de Ciències Clíniques, IDIBELL, University of Barcelona, Bellvitge Hospital, Barcelona, Spain
| | - I. Herrero-Fresneda
- Nephrology Laboratory, Departament de Ciències Clíniques, IDIBELL, University of Barcelona, Bellvitge Hospital, Barcelona, Spain
| | - J. M. Grinyó
- Nephrology Laboratory, Departament de Ciències Clíniques, IDIBELL, University of Barcelona, Bellvitge Hospital, Barcelona, Spain
- Servei de Nefrologia, Department of Nephrology, Hospital Universitari de Bellvitge, University of Barcelona, IDIBELL, Feixa Llarga s/n, L’Hospitalet de Llobregat, 08907 Barcelona, Spain
| | - J. M. Cruzado
- Nephrology Laboratory, Departament de Ciències Clíniques, IDIBELL, University of Barcelona, Bellvitge Hospital, Barcelona, Spain
- Servei de Nefrologia, Department of Nephrology, Hospital Universitari de Bellvitge, University of Barcelona, IDIBELL, Feixa Llarga s/n, L’Hospitalet de Llobregat, 08907 Barcelona, Spain
| |
Collapse
|