1
|
Sinha SK, Nicholas SB. Pathomechanisms of Diabetic Kidney Disease. J Clin Med 2023; 12:7349. [PMID: 38068400 PMCID: PMC10707303 DOI: 10.3390/jcm12237349] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/15/2023] [Accepted: 11/22/2023] [Indexed: 03/15/2024] Open
Abstract
The worldwide occurrence of diabetic kidney disease (DKD) is swiftly rising, primarily attributed to the growing population of individuals affected by type 2 diabetes. This surge has been transformed into a substantial global concern, placing additional strain on healthcare systems already grappling with significant demands. The pathogenesis of DKD is intricate, originating with hyperglycemia, which triggers various mechanisms and pathways: metabolic, hemodynamic, inflammatory, and fibrotic which ultimately lead to renal damage. Within each pathway, several mediators contribute to the development of renal structural and functional changes. Some of these mediators, such as inflammatory cytokines, reactive oxygen species, and transforming growth factor β are shared among the different pathways, leading to significant overlap and interaction between them. While current treatment options for DKD have shown advancement over previous strategies, their effectiveness remains somewhat constrained as patients still experience residual risk of disease progression. Therefore, a comprehensive grasp of the molecular mechanisms underlying the onset and progression of DKD is imperative for the continued creation of novel and groundbreaking therapies for this condition. In this review, we discuss the current achievements in fundamental research, with a particular emphasis on individual factors and recent developments in DKD treatment.
Collapse
Affiliation(s)
- Satyesh K. Sinha
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA;
- College of Medicine, Charles R Drew University of Medicine and Science, Los Angeles, CA 90059, USA
| | - Susanne B. Nicholas
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA;
| |
Collapse
|
2
|
Pan D, Xu L, Guo M. The role of protein kinase C in diabetic microvascular complications. Front Endocrinol (Lausanne) 2022; 13:973058. [PMID: 36060954 PMCID: PMC9433088 DOI: 10.3389/fendo.2022.973058] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 07/25/2022] [Indexed: 11/17/2022] Open
Abstract
Protein kinase C (PKC) is a family of serine/threonine protein kinases, the activation of which plays an important role in the development of diabetic microvascular complications. The activation of PKC under high-glucose conditions stimulates redox reactions and leads to an accumulation of redox stress. As a result, various types of cells in the microvasculature are influenced, leading to changes in blood flow, microvascular permeability, extracellular matrix accumulation, basement thickening and angiogenesis. Structural and functional disorders further exacerbate diabetic microvascular complications. Here, we review the roles of PKC in the development of diabetic microvascular complications, presenting evidence from experiments and clinical trials.
Collapse
Affiliation(s)
- Deng Pan
- Xiyuan hospital of China Academy of Chinese Medical Sciences, Beijing, China
- National Clinical Research Centre for Chinese Medicine Cardiology, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China
- Graduate School of Beijing University of Chinese Medicine, Beijing, China
| | - Lin Xu
- Gynecological Department of Traditional Chinese Medicine, China-Japan Friendship Hospital, Beijing, China
| | - Ming Guo
- Xiyuan hospital of China Academy of Chinese Medical Sciences, Beijing, China
- National Clinical Research Centre for Chinese Medicine Cardiology, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China
| |
Collapse
|
3
|
Xiao Q, He J, Lei A, Xu H, Zhang L, Zhou P, Jiang G, Zhou J. PPARγ enhances ILC2 function during allergic airway inflammation via transcription regulation of ST2. Mucosal Immunol 2021; 14:468-478. [PMID: 32811992 DOI: 10.1038/s41385-020-00339-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/21/2020] [Accepted: 07/26/2020] [Indexed: 02/07/2023]
Abstract
Group 2 innate lymphoid cells (ILC2s) represent the major player during hyperresponsive airway inflammation. Peroxisome proliferator-activated receptor-γ (PPARγ) was highly expressed on ILC2 and its potential role in asthma has been suggested. However, the detailed mechanism underlying the effects of PPARγ on ILC2-induced airway inflammation remains to be fully understood. Here we identified PPARγ as a positive regulator of lung ILC2. Expression of PPARγ on ILC2 was dramatically induced upon interleukin-33 (IL-33) challenge. Deficiency of PPARγ in hematopoietic system in mice (PPARγfl/fl Vav1Cre) significantly impaired the function of ILC2 in lung, which led to apparent alleviation of airway inflammation in response to IL-33 or Papain challenge, when compared with those in PPARγfl/fl littermates control. Mechanistic studies identified IL-33 receptor ST2 as a transcriptional target of PPARγ. Overexpression of ST2 rescued the functional defects of ILC2 lacking PPARγ. Collectively, these results demonstrated PPARγ as an important regulator of ILC2 during allergic airway inflammation, which sheds new lights on the importance of PPARγ in asthma.
Collapse
Affiliation(s)
- Qiang Xiao
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Immunology, School of Basic Medical Sciences, Tianjin, China.,Department of Clinical laboratory, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China
| | - Juan He
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Immunology, School of Basic Medical Sciences, Tianjin, China.,Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou, China
| | - Aihua Lei
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hengyang, China
| | - Haixu Xu
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Immunology, School of Basic Medical Sciences, Tianjin, China
| | - Lijuan Zhang
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Immunology, School of Basic Medical Sciences, Tianjin, China
| | - Pan Zhou
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Immunology, School of Basic Medical Sciences, Tianjin, China
| | - Guanmin Jiang
- Department of Clinical laboratory, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China
| | - Jie Zhou
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Immunology, School of Basic Medical Sciences, Tianjin, China.
| |
Collapse
|
4
|
Zhou G, Han X, Wu Z, Shi Q, Bao X. Rosiglitazone accelerates wound healing by improving endothelial precursor cell function and angiogenesis in db/db mice. PeerJ 2019; 7:e7815. [PMID: 31637120 PMCID: PMC6800979 DOI: 10.7717/peerj.7815] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/02/2019] [Indexed: 01/18/2023] Open
Abstract
Background & Aims Endothelial precursor cell (EPC) dysfunction is one of the risk factors for diabetes mellitus (DM) which results in delayed wound healing. Rosiglitazone (RSG) is a frequently prescribed oral glucose-lowering drug. Previous studies have shown the positive effects of RSG on ameliorating EPC dysfunction in diabetic patients. Interestingly, knowledge about RSG with regard to the wound healing process caused by DM is scarce. Therefore, in this study, we investigated the possible actions of RSG on wound healing and the related mechanisms involved in db/db diabetic mice. Methods Db/db mice with spontaneous glucose metabolic disorder were used as a type 2 DM model. RSG (20 mg/kg/d, i.g.,) was administered for 4 weeks before wound creation and bone marrow derived EPC (BM-EPC) isolation. Wound closure was assessed by wound area and CD31 staining. Tubule formation and migration assays were used to judge the function of the BM-EPCs. The level of vascular endothelial growth factor (VEGF), stromal cell derived factor-1α (SDF-1α) and insulin signaling was determined by ELISA. Cell viability of the BM-EPCs was measured by CCK-8 assay. Results RSG significantly accelerated wound healing and improved angiogenesis in db/db mice. Bioactivities of tube formation and migration were decreased in db/db mice but were elevated by RSG. Level of both VEGF and SDF-1α was increased by RSG in the BM-EPCs of db/db mice. Insulin signaling was elevated by RSG reflected in the phosphorylated-to-total AKT in the BM-EPCs. In vitro, RSG improved impaired cell viability and tube formation of BM-EPCs induced by high glucose, but this was prevented by the VEGF inhibitor avastin. Conclusion Our data demonstrates that RSG has benefits for wound healing and angiogenesis in diabetic mice, and was partially associated with improvement of EPC function through activation of VEGF and stimulation of SDF-1α in db/db mice.
Collapse
Affiliation(s)
- Guoliang Zhou
- Department of Pharmacy, School of Life and Health Sciences, Anhui Science and Technology University, Fengyang, Anhui, China
| | - Xue Han
- Laboratory Animal Center, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang Province, China
| | - Zhiheng Wu
- School of Clinical Medicine, Wannan Medicial Colledge, Wuhu, Anhui, China
| | - Qiaojuan Shi
- Laboratory Animal Center, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang Province, China
| | - Xiaogang Bao
- Department of Orthopedic Surgery, Spine Center, Changzheng Hospital, Second Military Medical University, Shanghai, China
| |
Collapse
|
5
|
Zheng X, Soroush F, Long J, Hall ET, Adishesha PK, Bhattacharya S, Kiani MF, Bhalla V. Murine glomerular transcriptome links endothelial cell-specific molecule-1 deficiency with susceptibility to diabetic nephropathy. PLoS One 2017; 12:e0185250. [PMID: 28934365 PMCID: PMC5608371 DOI: 10.1371/journal.pone.0185250] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 09/08/2017] [Indexed: 01/03/2023] Open
Abstract
Diabetic nephropathy (DN) is the leading cause of kidney disease; however, there are no early biomarkers and no cure. Thus, there is a large unmet need to predict which individuals will develop nephropathy and to understand the molecular mechanisms that govern this susceptibility. We compared the glomerular transcriptome from mice with distinct susceptibilities to DN at four weeks after induction of diabetes, but before histologic injury, and identified differential regulation of genes that modulate inflammation. From these genes, we identified endothelial cell specific molecule-1 (Esm-1), as a glomerular-enriched determinant of resistance to DN. Glomerular Esm-1 mRNA and protein were lower in DN-susceptible, DBA/2, compared to DN-resistant, C57BL/6, mice. We demonstrated higher Esm-1 secretion from primary glomerular cultures of diabetic mice, and high glucose was sufficient to increase Esm-1 mRNA and protein secretion in both strains of mice. However, induction was significantly attenuated in DN-susceptible mice. Urine Esm-1 was also significantly higher only in DN-resistant mice. Moreover, using intravital microscopy and a biomimetic microfluidic assay, we showed that Esm-1 inhibited rolling and transmigration in a dose-dependent manner. For the first time we have uncovered glomerular-derived Esm-1 as a potential non-invasive biomarker of DN. Esm-1 inversely correlates with disease susceptibility and inhibits leukocyte infiltration, a critical factor in protecting the kidney from DN.
Collapse
Affiliation(s)
- Xiaoyi Zheng
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Fariborz Soroush
- Department of Mechanical Engineering, College of Engineering, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Jin Long
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Evan T. Hall
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Puneeth K. Adishesha
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Sanchita Bhattacharya
- Institute of Computational Health Sciences, University of California, San Francisco, California, United States of America
| | - Mohammad F. Kiani
- Department of Mechanical Engineering, College of Engineering, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Vivek Bhalla
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail:
| |
Collapse
|
6
|
Ku YH, Cho BJ, Kim MJ, Lim S, Park YJ, Jang HC, Choi SH. Rosiglitazone increases endothelial cell migration and vascular permeability through Akt phosphorylation. BMC Pharmacol Toxicol 2017; 18:62. [PMID: 28854981 PMCID: PMC5577739 DOI: 10.1186/s40360-017-0169-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Accepted: 08/11/2017] [Indexed: 02/06/2023] Open
Abstract
Background Thiazolidinediones (TZDs), peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists, exhibit anti-inflammatory and antioxidant properties and inhibit endothelial inflammation and dysfunction, which is anti-atherogenic. However, fluid retention, which may lead to congestive heart failure and peripheral edema, is also a concern, which may result from endothelial cell leakage. In the current study, we examined the effects of PPAR-γ agonists on vascular endothelial cell migration and permeability in order to determine its underlying mechanisms. Methods We used rosiglitazone and conducted cell migration assay and permeability assay using HUVEC cells and measured vascular permeability and leakage in male C57BL/6 mice. Results Rosiglitazone significantly promoted endothelial cell migration and induced permeability via activation of phosphatidylinositol-3-kinase (PI3K) – Akt or protein kinase C (PKC)β. In addition, rosiglitazone increased vascular endothelial growth factor (VEGF) expression and suppressed expression of tight junction proteins (JAM-A and ZO-1), which might promote neovascularization and vascular leakage. These phenomena were reduced by Akt inhibition. Conclusions Vascular endothelial cell migration and permeability change through Akt phosphorylation might be a mechanism of induced fluid retention and peripheral tissue edema by TZD.
Collapse
Affiliation(s)
- Yun Hyi Ku
- Department of Internal Medicine, Korea Cancer Center Hospital, Seoul, South Korea
| | - Bong-Jun Cho
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Min Joo Kim
- Department of Internal Medicine, Korea Cancer Center Hospital, Seoul, South Korea
| | - Soo Lim
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Young Joo Park
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Hak C Jang
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Sung Hee Choi
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea. .,, 166 Gumi-dong, Bundang-gu, Seongnam-si, Gyeonggi-do, 463-707, Republic of Korea.
| |
Collapse
|
7
|
Rapp J, Kiss E, Meggyes M, Szabo-Meleg E, Feller D, Smuk G, Laszlo T, Sarosi V, Molnar TF, Kvell K, Pongracz JE. Increased Wnt5a in squamous cell lung carcinoma inhibits endothelial cell motility. BMC Cancer 2016; 16:915. [PMID: 27876017 PMCID: PMC5120464 DOI: 10.1186/s12885-016-2943-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 11/09/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Angiogenesis is important both in normal tissue function and disease and represents a key target in lung cancer (LC) therapy. Unfortunately, the two main subtypes of non-small-cell lung cancers (NSCLC) namely, adenocarcinoma (AC) and squamous cell carcinoma (SCC) respond differently to anti-angiogenic e.g. anti-vascular endothelial growth factor (VEGF)-A treatment with life-threatening side effects, often pulmonary hemorrhage in SCC. The mechanisms behind such adverse reactions are still largely unknown, although peroxisome proliferator activator receptor (PPAR) gamma as well as Wnt-s have been named as molecular regulators of the process. As the Wnt microenvironments in NSCLC subtypes are drastically different, we hypothesized that the particularly high levels of non-canonical Wnt5a in SCC might be responsible for alterations in blood vessel growth and result in serious adverse reactions. METHODS PPARgamma, VEGF-A, Wnt5a, miR-27b and miR-200b levels were determined in resected adenocarcinoma and squamous cell carcinoma samples by qRT-PCR and TaqMan microRNA assay. The role of PPARgamma in VEGF-A expression, and the role of Wnts in overall regulation was investigated using PPARgamma knock-out mice, cancer cell lines and fully human, in vitro 3 dimensional (3D), distal lung tissue aggregates. PPARgamma mRNA and protein levels were tested by qRT-PCR and immunohistochemistry, respectively. PPARgamma activity was measured by a PPRE reporter system. The tissue engineered lung tissues expressing basal level and lentivirally delivered VEGF-A were treated with recombinant Wnts, chemical Wnt pathway modifiers, and were subjected to PPARgamma agonist and antagonist treatment. RESULTS PPARgamma down-regulation and VEGF-A up-regulation are characteristic to both AC and SCC. Increased VEGF-A levels are under direct control of PPARgamma. PPARgamma levels and activity, however, are under Wnt control. Imbalance of both canonical (in AC) and non-canonical (in SCC) Wnts leads to PPARgamma down-regulation. While canonical Wnts down-regulate PPARgamma directly, non-canonical Wnt5a increases miR27b that is known regulator of PPARgamma. CONCLUSION During carcinogenesis the Wnt microenvironment alters, which can downregulate PPARgamma leading to increased VEGF-A expression. Differences in the Wnt microenvironment in AC and SCC of NSCLC lead to PPARgamma decrease via mechanisms that differentially alter endothelial cell motility and branching which in turn can influence therapeutic response.
Collapse
MESH Headings
- Adenocarcinoma/blood supply
- Adenocarcinoma/metabolism
- Adenocarcinoma/pathology
- Animals
- Biomarkers, Tumor
- Carcinoma, Non-Small-Cell Lung/blood supply
- Carcinoma, Non-Small-Cell Lung/metabolism
- Carcinoma, Non-Small-Cell Lung/pathology
- Carcinoma, Squamous Cell/blood supply
- Carcinoma, Squamous Cell/metabolism
- Carcinoma, Squamous Cell/pathology
- Cell Movement
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Female
- Gene Expression Regulation, Neoplastic
- Humans
- Lung Neoplasms/blood supply
- Lung Neoplasms/metabolism
- Lung Neoplasms/pathology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- MicroRNAs/genetics
- Neovascularization, Pathologic/metabolism
- Neovascularization, Pathologic/pathology
- PPAR gamma/physiology
- Tumor Cells, Cultured
- Tumor Microenvironment
- Vascular Endothelial Growth Factor A/metabolism
- Wnt-5a Protein/metabolism
Collapse
Affiliation(s)
- J Rapp
- Department of Pharmaceutical Biotechnology, School of Pharmacy, University of Pecs, 2 Rokus Str, Pecs, 7624, Hungary
- János Szentágothai Research Centre, University of Pécs, 20 Ifjúság Str, Pecs, 7622, Hungary
- Humeltis Ltd, János Szentágothai Research Center, University of Pécs, 20 Ifjúság Str, Pécs, 7622, Hungary
| | - E Kiss
- Department of Pharmaceutical Biotechnology, School of Pharmacy, University of Pecs, 2 Rokus Str, Pecs, 7624, Hungary
- János Szentágothai Research Centre, University of Pécs, 20 Ifjúság Str, Pecs, 7622, Hungary
- Humeltis Ltd, János Szentágothai Research Center, University of Pécs, 20 Ifjúság Str, Pécs, 7622, Hungary
| | - M Meggyes
- Medical Microbiology and Immunity, University of Pécs, 12 Szigeti Str, Pécs, 7624, Hungary
- Humeltis Ltd, János Szentágothai Research Center, University of Pécs, 20 Ifjúság Str, Pécs, 7622, Hungary
| | - E Szabo-Meleg
- Biophysics, University of Pécs, 12 Szigeti Str, Pécs, 7624, Hungary
- János Szentágothai Research Centre, University of Pécs, 20 Ifjúság Str, Pecs, 7622, Hungary
| | - D Feller
- Department of Pharmaceutical Biotechnology, School of Pharmacy, University of Pecs, 2 Rokus Str, Pecs, 7624, Hungary
- János Szentágothai Research Centre, University of Pécs, 20 Ifjúság Str, Pecs, 7622, Hungary
- Humeltis Ltd, János Szentágothai Research Center, University of Pécs, 20 Ifjúság Str, Pécs, 7622, Hungary
| | - G Smuk
- Pathology, University of Pécs, 12 Szigeti Str, Pécs, 7624, Hungary
| | - T Laszlo
- Pathology, University of Pécs, 12 Szigeti Str, Pécs, 7624, Hungary
| | - V Sarosi
- Internal Medicine, Pulmonology, University of Pécs, 2 Rakoczi Str, Pécs, 7623, Hungary
| | - T F Molnar
- Operational Medicine, University of Pécs, 12 Szigeti Str, Pécs, 7624, Hungary
- Department of Surgery, Thoracic Surgery Unit, Petz A Hospital, 2-4 Vasvari Str, Győr, 9023, Hungary
| | - K Kvell
- Department of Pharmaceutical Biotechnology, School of Pharmacy, University of Pecs, 2 Rokus Str, Pecs, 7624, Hungary
- János Szentágothai Research Centre, University of Pécs, 20 Ifjúság Str, Pecs, 7622, Hungary
| | - J E Pongracz
- Department of Pharmaceutical Biotechnology, School of Pharmacy, University of Pecs, 2 Rokus Str, Pecs, 7624, Hungary.
- János Szentágothai Research Centre, University of Pécs, 20 Ifjúság Str, Pecs, 7622, Hungary.
- Humeltis Ltd, János Szentágothai Research Center, University of Pécs, 20 Ifjúság Str, Pécs, 7622, Hungary.
| |
Collapse
|
8
|
Mi X, Tang W, Chen X, Liu F, Tang X. Mitofusin 2 attenuates the histone acetylation at collagen IV promoter in diabetic nephropathy. J Mol Endocrinol 2016; 57:233-249. [PMID: 27997345 DOI: 10.1530/jme-16-0031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 10/03/2016] [Indexed: 12/15/2022]
Abstract
Extracellular matrix (ECM) increase in diabetic nephropathy (DN) is closely related to mitochondrial dysfunction. The mechanism of protective function of mitofusin 2 (Mfn2) for mitochondria remains largely unknown. In this study, the molecular mechanisms for the effect of Mfn2 on mitochondria and subsequent collagen IV expression in DN were investigated. Ras-binding-deficient mitofusin 2 (Mfn2-Ras(Δ)) were overexpressed in rat glomerular mesangial cells, and then the cells were detected for mitochondrial morphology, cellular reactive oxygen species (ROS), mRNA and protein expression of collagen IV with advanced glycation end-product (AGE) stimulation. Preliminary results reveal that the mitochondrial dysfunction and the increased synthesis of collagen IV after AGE stimulation were reverted by Mfn2-Ras(Δ) overexpression. Bioinformatical computations were performed to search transcriptional factor motifs in the promoter region of collagen IV. Three specific regions for TFAP2A binding were identified, followed by validation with chromatin immunoprecipitation experiments. Knocking down TFAP2A significantly decreased the TF binding in the first two regions and the gene expression of collagen IV. Furthermore, results reveal that Mfn2-Ras(Δ) overexpression significantly mitigated TFAP2A binding and also reverted the histone acetylation at Regions 1 and 2 after AGE stimulation. In streptozotocin-induced diabetic rats, Mfn2-Ras(Δ) overexpression also ameliorated glomerular mesangial lesions with decreased collagen IV expression, accompanied by decreased acetylation and TFAP2A binding at Region 1. In conclusion, this study highlights the pathway by which mitochondria affect the histone acetylation of gene promoter and provides a new potential therapy approach for DN.
Collapse
Affiliation(s)
- Xuhua Mi
- Division of NephrologyWest China Hospital, Sichuan University, Chengdu, China
| | - Wanxin Tang
- Division of NephrologyWest China Hospital, Sichuan University, Chengdu, China
| | - Xiaolei Chen
- Division of NephrologyWest China Hospital, Sichuan University, Chengdu, China
| | - Fei Liu
- Division of NephrologyWest China Hospital, Sichuan University, Chengdu, China
| | - Xiaohong Tang
- Division of NephrologyWest China Hospital, Sichuan University, Chengdu, China
| |
Collapse
|
9
|
Role of NADPH Oxidase in Metabolic Disease-Related Renal Injury: An Update. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:7813072. [PMID: 27597884 PMCID: PMC5002489 DOI: 10.1155/2016/7813072] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 07/17/2016] [Indexed: 01/09/2023]
Abstract
Metabolic syndrome has been linked to an increased risk of chronic kidney disease. The underlying pathogenesis of metabolic disease-related renal injury remains obscure. Accumulating evidence has shown that NADPH oxidase is a major source of intrarenal oxidative stress and is upregulated by metabolic factors leading to overproduction of ROS in podocytes, endothelial cells, and mesangial cells in glomeruli, which is closely associated with the initiation and progression of glomerular diseases. This review focuses on the role of NADPH oxidase-induced oxidative stress in the pathogenesis of metabolic disease-related renal injury. Understanding of the mechanism may help find potential therapeutic strategies.
Collapse
|
10
|
Xing Y, Ye S, Chen Y, Hu W, Chen Y. Hydrochloride pioglitazone protects diabetic rats against podocyte injury through preserving glomerular podocalyxin expression. ACTA ACUST UNITED AC 2015; 58:630-9. [PMID: 25211446 DOI: 10.1590/0004-2730000003141] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 06/04/2014] [Indexed: 01/07/2023]
Abstract
OBJECTIVE We sought to test the effect of different dosages of pioglitazone (PIO) on the glomerular expression of podocalyxin and urinary sediment podocalyxin excretion and to explore the potential renoprotective mechanism. MATERIALS AND METHODS Type 1 diabetes induced with streptozotocin (65 mg/kg) in 36 male Sprague-Dawley rats were randomly allocated to be treated with vehicle or 10, 20, 30 mg/kg/d PIO respectively for 8 weeks. Eight rats were enrolled in the normal control group. RESULTS At 8th week, rats were sacrificed for the observation of kidney injury through electron microscope. Glomerular podocalyxin production including mRNA and protein were determined by RT-PCR and immunohistochemistry respectively. Levels of urinary albumin excretion and urinary sediment podocalyxin, kidney injury index were all significantly increased, whereas expression of glomerular podocalyxin protein and mRNA were decreased significantly in diabetic rats compared to normal control. Dosages-dependent analysis revealed that protective effect of PIO ameliorated the physiopathological changes and reached a peak at dosage of 20 mg/kg/d. CONCLUSION PIO could alleviate diabetic kidney injury in a dose-dependent pattern and the role may be associated with restraining urinary sediment podocalyxin excretion and preserving the glomerular podocalyxin expression.
Collapse
Affiliation(s)
- Yan Xing
- Department of Endocrinology, Anhui Provincial Hospital, Hefei, China
| | - Shandong Ye
- Department of Endocrinology, Anhui Provincial Hospital, Hefei, China
| | - Yumi Chen
- Department of Nephrology, Anhui Provincial Hospital, Hefei, China
| | - Wen Hu
- Department of Pathology, Anhui Provincial Hospital, Hefei, China
| | - Yan Chen
- Endocrinological Laboratory, Anhui Provincial Hospital, Hefei, China
| |
Collapse
|
11
|
Rosiglitzone suppresses angiotensin II-induced production of KLF5 and cell proliferation in rat vascular smooth muscle cells. PLoS One 2015; 10:e0123724. [PMID: 25874449 PMCID: PMC4397085 DOI: 10.1371/journal.pone.0123724] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 03/05/2015] [Indexed: 01/14/2023] Open
Abstract
Krüppel-like factor (KLF) 5, which initiates vascular smooth muscle cell (VSMC) proliferation, also participates in Angiotensin (Ang) II-induced vascular remodeling. The protective effect of rosiglitazone on vascular remodeling may be due to their impact on VSMC proliferation. However, the underlying mechanisms involved remain unclear. This study was designed to investigate whether the antiproliferation effects of rosiglitazone are mediated by regulating Ang II/KLF5 response. We found that, in aortas of Ang II-infused rats, vascular remodeling and KLF5 expression were markedly increased, and its target gene cyclin D1 was overexpressed. Co-treatment with rosiglitazone diminished these changes. In growth-arrested VSMCs, PPAR-γ agonists (rosiglitazone and 15d-PGJ2) dose-dependently inhibited Ang II-induced cell proliferation and expression of KLF5 and cyclin D1. Moreover, these effects were attenuated by the PPAR-γ antagonists GW9662, bisphenol A diglycidyl ether and PPAR-γ specific siRNA. Furthermore, rosiglitazone inhibited Ang II-induced phosphorylation of protein kinase C (PKC) ζ and extracellular signal-regulated kinase (ERK) 1/2 and activation of early growth response protein (Egr). In conclusion, in Ang II-stimulated VSMCs, rosiglitazone might have an antiproliferative effect through mechanisms that include reducing KLF5 expression, and a crosstalk between PPAR-γ and PKCζ/ERK1/2/Egr may be involved in. These findings not only provide a previously unrecognized mechanism by which PPAR-γ agonists inhibit VSMC proliferation, but also document a novel evidence for the beneficial vascular effect of PPAR-γ activation.
Collapse
|
12
|
Gorin Y, Wauquier F. Upstream regulators and downstream effectors of NADPH oxidases as novel therapeutic targets for diabetic kidney disease. Mol Cells 2015; 38:285-96. [PMID: 25824546 PMCID: PMC4400302 DOI: 10.14348/molcells.2015.0010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 01/12/2015] [Indexed: 02/07/2023] Open
Abstract
Oxidative stress has been linked to the pathogenesis of diabetic nephropathy, the complication of diabetes in the kidney. NADPH oxidases of the Nox family, and in particular the homologue Nox4, are a major source of reactive oxygen species in the diabetic kidney and are critical mediators of redox signaling in glomerular and tubulointerstitial cells exposed to the diabetic milieu. Here, we present an overview of the current knowledge related to the understanding of the role of Nox enzymes in the processes that control mesangial cell, podocyte and tubulointerstitial cell injury induced by hyperglycemia and other predominant factors enhanced in the diabetic milieu, including the renin-angiotensin system and transforming growth factor-β. The nature of the upstream modulators of Nox enzymes as well as the downstream targets of the Nox NADPH oxidases implicated in the propagation of the redox processes that alter renal biology in diabetes will be highlighted.
Collapse
Affiliation(s)
- Yves Gorin
- Department of Medicine, University of Texas Health Science Center, San Antonio, Texas,
USA
| | - Fabien Wauquier
- Department of Medicine, University of Texas Health Science Center, San Antonio, Texas,
USA
| |
Collapse
|
13
|
Small DM, Morais C, Coombes JS, Bennett NC, Johnson DW, Gobe GC. Oxidative stress-induced alterations in PPAR-γ and associated mitochondrial destabilization contribute to kidney cell apoptosis. Am J Physiol Renal Physiol 2014; 307:F814-22. [PMID: 25122050 DOI: 10.1152/ajprenal.00205.2014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The mechanism(s) underlying renoprotection by peroxisome proliferator-activated receptor (PPAR)-γ agonists in diabetic and nondiabetic kidney disease are not well understood. Mitochondrial dysfunction and oxidative stress contribute to kidney disease. PPAR-γ upregulates proteins required for mitochondrial biogenesis. Our aim was to determine whether PPAR-γ has a role in protecting the kidney proximal tubular epithelium (PTE) against mitochondrial destabilisation and oxidative stress. HK-2 PTE cells were subjected to oxidative stress (0.2-1.0 mM H₂O₂) for 2 and 18 h and compared with untreated cells for apoptosis, mitosis (morphology/biomarkers), cell viability (MTT), superoxide (dihydroethidium), mitochondrial function (MitoTracker red and JC-1), ATP (luminescence), and mitochondrial ultrastructure. PPAR-γ, phospho-PPAR-γ, PPAR-γ coactivator (PGC)-1α, Parkin (Park2), p62, and light chain (LC)3β were investigated using Western blots. PPAR-γ was modulated using the agonists rosiglitazone, pioglitazone, and troglitazone. Mitochondrial destabilization increased with H₂O₂concentration, ATP decreased (2 and 18 h; P < 0.05), Mitotracker red and JC-1 fluorescence indicated loss of mitochondrial membrane potential, and superoxide increased (18 h, P < 0.05). Electron microscopy indicated sparse mitochondria, with disrupted cristae. Mitophagy was evident at 2 h (Park2 and LC3β increased; p62 decreased). Impaired mitophagy was indicated by p62 accumulation at 18 h (P < 0.05). PPAR-γ expression decreased, phospho-PPAR-γ increased, and PGC-1α decreased (2 h), indicating aberrant PPAR-γ activation and reduced mitochondrial biogenesis. Cell viability decreased (2 and 18 h, P < 0.05). PPAR-γ agonists promoted further apoptosis. In summary, oxidative stress promoted mitochondrial destabilisation in kidney PTE, in association with increased PPAR-γ phosphorylation. PPAR-γ agonists failed to protect PTE. Despite positive effects in other tissues, PPAR-γ activation appears to be detrimental to kidney PTE health when oxidative stress induces damage.
Collapse
Affiliation(s)
- David M Small
- Centre for Kidney Disease Research, School of Medicine, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Christudas Morais
- Centre for Kidney Disease Research, School of Medicine, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia
| | - Jeff S Coombes
- Centre for Kidney Disease Research, School of Medicine, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia; School of Human Movement Studies, The University of Queensland, Brisbane, Queensland, Australia
| | - Nigel C Bennett
- Centre for Kidney Disease Research, School of Medicine, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia; UQ Centre for Clinical Research, The University of Queensland, Brisbane, Queensland, Australia; and
| | - David W Johnson
- Centre for Kidney Disease Research, School of Medicine, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia; Department of Nephrology, Princess Alexandra Hospital, Brisbane, Queensland, Australia
| | - Glenda C Gobe
- Centre for Kidney Disease Research, School of Medicine, The University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia;
| |
Collapse
|
14
|
Zhou P, Kannan R, Spee C, Sreekumar PG, Dou G, Hinton DR. Protection of retina by αB crystallin in sodium iodate induced retinal degeneration. PLoS One 2014; 9:e98275. [PMID: 24874187 PMCID: PMC4038555 DOI: 10.1371/journal.pone.0098275] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Accepted: 04/29/2014] [Indexed: 12/21/2022] Open
Abstract
Age-related macular degeneration (AMD) is a leading cause of blindness in the developed world. The retinal pigment epithelium (RPE) is a critical site of pathology in AMD and αB crystallin expression is increased in RPE and associated drusen in AMD. The purpose of this study was to investigate the role of αB crystallin in sodium iodate (NaIO3)-induced retinal degeneration, a model of AMD in which the primary site of pathology is the RPE. Dose dependent effects of intravenous NaIO3 (20-70 mg/kg) on development of retinal degeneration (fundus photography) and RPE and retinal neuronal loss (histology) were determined in wild type and αB crystallin knockout mice. Absence of αB crystallin augmented retinal degeneration in low dose (20 mg/kg) NaIO3-treated mice and increased retinal cell apoptosis which was mainly localized to the RPE layer. Generation of reactive oxygen species (ROS) was observed with NaIO3 in mouse and human RPE which increased further after αB crystallin knockout or siRNA knockdown, respectively. NaIO3 upregulated AKT phosphorylation and peroxisome proliferator–activator receptor–γ (PPARγ) which was suppressed after αB crystallin siRNA knockdown. Further, PPARγ ligand inhibited NaIO3-induced ROS generation. Our data suggest that αB crystallin plays a critical role in protection of NaIO3-induced oxidative stress and retinal degeneration in part through upregulation of AKT phosphorylation and PPARγ expression.
Collapse
Affiliation(s)
- Peng Zhou
- Doheny Eye Institute, Los Angeles, California, United States of America
| | - Ram Kannan
- Doheny Eye Institute, Los Angeles, California, United States of America
| | - Christine Spee
- Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, United States of America
| | | | - Guorui Dou
- Doheny Eye Institute, Los Angeles, California, United States of America
| | - David R. Hinton
- Departments of Pathology, Keck School of Medicine of the University of Southern California, Los Angeles, California, United States of America
- Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, United States of America
- * E-mail:
| |
Collapse
|
15
|
Abstract
Diabetic retinopathy is a common condition that occurs in patients with diabetes with long-standing hyperglycemia that is characterized by inappropriate angiogenesis. This pathological angiogenesis could be a sort of physiological proliferative response to injury by the endothelium. Recent studies suggested that reactive oxygen species (ROS) play a significant role in this angiogenesis. Vascular endothelial growth factor (VEGF) is a potent angiogenic growth factor that plays a significant role in diabetic retinopathy. The interaction between VEGF and ROS, and theirs in turn with pro- and anti-inflammatory cytokines and anti-inflammatory bioactive lipid molecules such as lipoxins, resolvins, protectins, and maresins is particularly relevant to understand the pathophysiology of diabetic retinopathy and develop future therapeutic interventions.
Collapse
Affiliation(s)
- Qi Ma
- a Department of Food Science and Nutrition , Zhejiang University , Hangzhou , 310029 , China
| | | | | | | |
Collapse
|
16
|
Gorin Y, Block K. Nox4 and diabetic nephropathy: with a friend like this, who needs enemies? Free Radic Biol Med 2013; 61:130-42. [PMID: 23528476 PMCID: PMC3716866 DOI: 10.1016/j.freeradbiomed.2013.03.014] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 03/12/2013] [Accepted: 03/16/2013] [Indexed: 12/19/2022]
Abstract
Oxidative stress has been linked to the pathogenesis of diabetic nephropathy, a complication of diabetes in the kidney. NADPH oxidases of the Nox family are a major source of reactive oxygen species in the diabetic kidney and are critical mediators of redox signaling in glomerular and tubulointerstitial cells exposed to the diabetic milieu. Here, we present an overview of the current understanding of the roles of Nox catalytic and regulatory subunits in the processes that control mesangial cell, podocyte, and tubulointerstitial cell injury induced by hyperglycemia and other predominant factors enhanced in the diabetic milieu, including the renin-angiotensin system and transforming growth factor-β. The role of the Nox isoform Nox4 in the redox processes that alter renal biology in diabetes is highlighted.
Collapse
Affiliation(s)
- Yves Gorin
- Department of Medicine, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA.
| | - Karen Block
- Department of Medicine, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA; Audie L. Murphy Memorial Hospital Division, South Texas Veterans Health Care System, San Antonio, TX 78229, USA.
| |
Collapse
|
17
|
Abstract
Oxidative stress has been linked to the pathogenesis of the major complications of diabetes in the kidney, the heart, the eye or the vasculature. NADPH oxidases of the Nox family are a major source of ROS (reactive oxygen species) and are critical mediators of redox signalling in cells from different organs afflicted by the diabetic milieu. In the present review, we provide an overview of the current knowledge related to the understanding of the role of Nox in the processes that control cell injury induced by hyperglycaemia and other predominant factors enhanced in diabetes, including the renin–angiotensin system, TGF-β (transforming growth factor-β) and AGEs (advanced glycation end-products). These observations support a critical role for Nox homologues in diabetic complications and indicate that NADPH oxidases are an important therapeutic target. Therefore the design and development of small-molecule inhibitors that selectively block Nox oxidases appears to be a reasonable approach to prevent or retard the complications of diabetes in target organs. The bioefficacy of these agents in experimental animal models is also discussed in the present review.
Collapse
|
18
|
Wu T, Zhang B, Ye F, Xiao Z. A potential role for caveolin-1 in VEGF-induced fibronectin upregulation in mesangial cells: involvement of VEGFR2 and Src. Am J Physiol Renal Physiol 2013; 304:F820-30. [DOI: 10.1152/ajprenal.00294.2012] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
VEGF is known to be an endothelial cell mitogen that stimulates angiogenesis by promoting endothelial cell survival, proliferation, migration, and differentiation. Recent studies have suggested that VEGF may play a pivotal role in glomerular sclerosis through extracellular matrix protein (ECM) accumulation, although the signaling mechanism is still unclear. The GTPase RhoA has been implicated in VEGF-induced type IV collagen accumulation in some settings. Here we study the role of different VEGF receptors and membrane microdomain caveolae in VEGF-induced RhoA activation and fibronectin upregulation in mesangial cells (MCs). In primary rat MC, VEGF time and dose dependently increased fibronectin production. Rho pathway inhibition blocked VEGF-induced fibronectin upregulation. VEGF-induced RhoA activation was prevented by disrupting caveolae with cholesterol depletion and rescued by cholesterol repletion. VEGF stimulation led to a markedly increased VEGFR2/caveolin-1 but failed to increase VEGFR1/caveolin-1 association. VEGF also increased caveolin-1/Src association and activated Src, and Src inhibitor blocked RhoA activation and fibronectin upregulation. Src-mediated phosphorylation of caveolin-1 on Y14 has also been implicated in signaling responses. Overexpression of nonphosphorylatable caveolin-1 Y14A prevented VEGF-induced RhoA activation and fibronectin upregulation. In vivo, although VEGFR1 and VEGFR2 protein levels were both increased in the kidney cortices of diabetic rats, VEGFR2/caveolin-1 association but not VEGFR1/caveolin-1 association was significantly increased. In conclusion, VEGF-induced RhoA activation and fibronectin upregulation require caveolae and caveolin-1 interaction with VEGFR2 and Src. Interference with caveolin/-ae signaling may provide new avenues for the treatment of fibrotic renal disease.
Collapse
Affiliation(s)
- Tingting Wu
- Department of Biochemistry, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei, People's Republic of China
| | - Baifang Zhang
- Department of Biochemistry, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei, People's Republic of China
| | - Feng Ye
- Department of Biochemistry, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei, People's Republic of China
| | - Zeling Xiao
- Department of Biochemistry, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei, People's Republic of China
| |
Collapse
|
19
|
Effects of high glucose on vascular endothelial growth factor synthesis and secretion in aortic vascular smooth muscle cells from obese and lean Zucker rats. Int J Mol Sci 2012; 13:9478-9488. [PMID: 22949809 PMCID: PMC3431807 DOI: 10.3390/ijms13089478] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 06/22/2012] [Accepted: 07/20/2012] [Indexed: 01/17/2023] Open
Abstract
Type 1 diabetes is characterized by insulin deficiency, type 2 by both insulin deficiency and insulin resistance: in both conditions, hyperglycaemia is accompanied by an increased cardiovascular risk, due to increased atherosclerotic plaque formation/instabilization and impaired collateral vessel formation. An important factor in these phenomena is the Vascular Endothelial Growth Factor (VEGF), a molecule produced also by Vascular Smooth Muscle Cells (VSMC). We aimed at evaluating the role of high glucose on VEGF-A164 synthesis and secretion in VSMC from lean insulin-sensitive and obese insulin-resistant Zucker rats (LZR and OZR). In cultured aortic VSMC from LZR and OZR incubated for 24 h with d-glucose (5.5, 15 and 25 mM) or with the osmotic controls l-glucose and mannitol, we measured VEGF-A164 synthesis (western, blotting) and secretion (western blotting and ELISA). We observed that: (i) d-glucose dose-dependently increases VEGF-A164 synthesis and secretion in VSMC from LZR and OZR (n = 6, ANOVA p = 0.002–0.0001); (ii) all the effects of 15 and 25 mM d-glucose are attenuated in VSMC from OZR vs. LZR (p = 0.0001); (iii) l-glucose and mannitol reproduce the VEGF-A164 modulation induced by d-glucose in VSMC from both LZR and OZR. Thus, glucose increases via an osmotic mechanism VEGF synthesis and secretion in VSMC, an effect attenuated in the presence of insulin resistance.
Collapse
|
20
|
The renoprotective actions of peroxisome proliferator-activated receptors agonists in diabetes. PPAR Res 2012; 2012:456529. [PMID: 22448165 PMCID: PMC3289856 DOI: 10.1155/2012/456529] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 11/21/2011] [Accepted: 11/21/2011] [Indexed: 12/17/2022] Open
Abstract
Pharmaceutical agonists of peroxisome proliferator-activated receptors (PPARs) are widely used in the management of type 2 diabetes, chiefly as lipid-lowering agents and oral hypoglycaemic agents. Although most of the focus has been placed on their cardiovascular effects, both positive and negative, these agents also have significant renoprotective actions in the diabetic kidney. Over and above action on metabolic control and effects on blood pressure, PPAR agonists also appear to have independent effects on a number of critical pathways that are implicated in the development and progression of diabetic kidney disease, including oxidative stress, inflammation, hypertrophy, and podocyte function. This review will examine these direct and indirect actions of PPAR agonists in the diabetic kidney and explore recent findings of clinical trials of PPAR agonists in patients with diabetes.
Collapse
|
21
|
Pereira LG, Arnoni CP, Maquigussa E, Cristovam PC, Dreyfuss J, Boim MA. (Pro)renin receptor: another member of the system controlled by angiotensin II? J Renin Angiotensin Aldosterone Syst 2011; 13:1-10. [PMID: 21997900 DOI: 10.1177/1470320311423280] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The prorenin receptor [(P)RR] is upregulated in the diabetic kidney and has been implicated in the high glucose (HG)-induced overproduction of profibrotic molecules by mesangial cells (MCs), which is mediated by ERK1/2 phosphorylation. The regulation of (P)RR gene transcription and the mechanisms by which HG increases (P)RR gene expression are not fully understood. Because intracellular levels of angiotensin II (AngII) are increased in MCs stimulated with HG, we used this in vitro system to evaluate the possible role of AngII in (P)RR gene expression and function by comparing the effects of AT1 receptor blockers (losartan or candesartan) and (P)RR mRNA silencing (siRNA) in human MCs (HMCs) stimulated with HG. HG induced an increase in (P)RR and fibronectin expression and in ERK1/2 phosphorylation. These effects were completely reversed by (P)RR siRNA and losartan but not by candesartan (an angiotensin receptor blocker that, in contrast to losartan, blocks AT1 receptor internalization). These results suggest that (P)RR gene activity may be controlled by intracellular AngII and that HG-induced ERK1/2 phosphorylation and fibronectin overproduction are primarily induced by (P)RR activation. This relationship between AngII and (P)RR may constitute an additional pathway of MC dysfunction in response to HG stimulation.
Collapse
Affiliation(s)
- Luciana G Pereira
- Department of Medicine, Renal Division, Federal University of São Paulo, São Paulo, Brazil
| | | | | | | | | | | |
Collapse
|
22
|
Wang X, Wang Z, Liu JZ, Hu JX, Chen HL, Li WL, Hai CX. Double antioxidant activities of rosiglitazone against high glucose-induced oxidative stress in hepatocyte. Toxicol In Vitro 2011; 25:839-47. [PMID: 21333731 DOI: 10.1016/j.tiv.2011.02.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 12/27/2010] [Accepted: 02/11/2011] [Indexed: 02/07/2023]
Abstract
Chronic hyperglycemia is the hallmark of diabetes and its complication. High glucose-induced excessive reactive oxygen species (ROS) production has been considered to play an important role in the development of diabetes. However, the influence of high glucose on the liver remains to be clarified. Rosiglitazone (RSG) is a member of thiazolidinediones (TDZs) family, which is the ligand of the of nuclear transcription factor peroxisome proliferator-activated receptor-γ (PPARγ), being used clinically for the treatment of type 2 diabetic patients through their insulin-sensitizing effect. In the present study, we investigated the cytotoxicity of high glucose in QZG hepatocytes and evaluated the protective effect of RSG. The results showed that high glucose significantly reduced cell viability through generation of ROS via activation of PKC, which was inhibited by RSG. On the one hand, RSG notably inhibited the activation of PKC induced by high glucose independent of PPARγ, leading to the decrease of ROS generation. On the other hand, RSG notably increased the expression of key antioxidant transcription factor Nrf2 and antioxidant enzyme HO-1 in a PPARγ-dependent manner, leading to the elimination of excessive ROS. In addition, RSG also inhibited the decrease of COX-2 expression induced by high glucose through activating PPARγ. Furthermore, the activation of Akt and MAPKs was involved in the effect of RSG on Nrf2, HO-1 and COX-2. In summary, our study supports the hypothesis that RSG protect hepatocytes from high glucose-induced toxicity through PPARγ-dependent and PPARγ-independent pathways.
Collapse
Affiliation(s)
- Xin Wang
- Department of Toxicology, Faculty of Preventive Medicine, The Fourth Military Medical University, Xi'an 710032, China
| | | | | | | | | | | | | |
Collapse
|
23
|
Yuan Y, Zhang A, Huang S, Ding G, Chen R. A PPARγ agonist inhibits aldosterone-induced mesangial cell proliferation by blocking ROS-dependent EGFR intracellular signaling. Am J Physiol Renal Physiol 2011; 300:F393-402. [PMID: 21123490 DOI: 10.1152/ajprenal.00418.2010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mesangial cell (MC) proliferation is a key feature in the pathogenesis of a number of renal diseases. Peroxisome proliferator-activated receptor-γ (PPARγ) has attracted considerable attention for its effects on stimulating cell differentiation and on inducing cell cycle arrest. We previously showed that aldosterone (Aldo) stimulates MC proliferation via the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway, which was dependent on reactive oxygen species (ROS)-mediated epithelial growth factor receptor (EGFR) transactivation (Huang S, Zhang A, Ding G, and Chen R. Am J Physiol Renal Physiol 296: F1323–F1333, 2009). In this study, we examined whether the PPARγ agonist rosiglitazone inhibited Aldo-induced MC proliferation by modulating ROS-dependent EGFR intracellular signaling. Rosiglitazone at 1–10 μM dose dependently inhibited Aldo-induced MC proliferation of cultured mouse MCs. The inhibitory effect was blocked by the PPARγ antagonist PD-68235, indicating that the rosiglitazone effect acted through PPARγ activation. Rosiglitazone also arrested Aldo-induced cell cycle progression and suppressed expression of cyclins D1 and A. Moreover, rosiglitazone dose dependently blocked Aldo-induced ROS production, EGFR phosphorylation, and PI3K/Akt activation. These results suggest that the PPARγ agonist rosiglitazone may inhibit Aldo-induced MC proliferation directly, by affecting ROS/EGFR/PI3K/Akt signaling pathways and cell cycle-regulatory proteins. PPARγ might be a novel therapeutic target against glomerular diseases.
Collapse
Affiliation(s)
- Yanggang Yuan
- Department of Nephrology, Nanjing Children's Hospital, Nanjing Medical University and
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Aihua Zhang
- Department of Nephrology, Nanjing Children's Hospital, Nanjing Medical University and
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Songming Huang
- Department of Nephrology, Nanjing Children's Hospital, Nanjing Medical University and
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Guixia Ding
- Department of Nephrology, Nanjing Children's Hospital, Nanjing Medical University and
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Ronghua Chen
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| |
Collapse
|
24
|
Resveratrol prevents hyperglycemia-induced endothelial dysfunction via activation of adenosine monophosphate-activated protein kinase. Biochem Biophys Res Commun 2009; 388:389-94. [PMID: 19666001 DOI: 10.1016/j.bbrc.2009.08.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2009] [Accepted: 08/04/2009] [Indexed: 11/20/2022]
Abstract
Endothelial dysfunction secondary to persistent hyperglycemia plays a key role in the development of type 2 diabetic vascular disease. The aim of the present study was to examine the protective effect of resveratrol against hyperglycemia-induced endothelial dysfunction. In cultured human umbilical vein endothelial cells (HUVECs), resveratrol (10-100 microM) concentration dependently enhanced phosphorylation of endothelial nitric oxide synthesis (eNOS) at Ser1177 and nitric oxide (NO) production. In addition, resveratrol can increase the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) at Thr172 and suppress high glucose-induced generation of superoxide anion. In mouse aortic rings, resveratrol (1-100 microM) elicited endothelium-dependent vasodilatations and alleviated high glucose-mediated endothelial dysfunction. All these beneficial effects of resveratrol on the endothelium were abolished by pharmacological antagonism of AMPK by compound C. These results provide new insight into the protective properties of resveratrol against endothelial dysfunction caused by high glucose, which is attributed to the AMPK mediated reduction of superoxide level.
Collapse
|