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Chen Y, Xiang W, Li X, Wang D, Qian C. Rosiglitazone prevents acute pancreatitis through inhibiting microRNA-26a expression. Exp Ther Med 2019; 18:1246-1252. [PMID: 31363368 PMCID: PMC6614723 DOI: 10.3892/etm.2019.7711] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 05/09/2019] [Indexed: 12/26/2022] Open
Abstract
The aim of the present study was to investigate the regulatory effect of rosiglitazone on the progression of acute pancreatitis (AP) and pancreas injury, and the underlying mechanism. An AP rat model was established using caerulein and validated by detection of amylase, lipase, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and transforming growth factor-β (TGF-β) serum levels. Pancreatic injury was assessed by pathological examination. The expression levels of microRNA (miR)-26a in AP rats and AR42J cells were analyzed using reverse transcription-quantitative PCR (RT-qPCR). Luciferase reporter gene assay was applied for detecting whether miR-26a bound to the target gene phosphatase and tensin homolog (PTEN). The regulatory effect of rosiglitazone on the PI3K/AKT signaling pathway was analyzed by western blot analysis. Results demonstrated that establishment of an AP model was successful with severe pancreas injury and classic AP phenotypes observed in rats. Increased serum expression of amylase, lipase, TNF-α, IL-6 and TGF-β were observed in AP rats. Rosiglitazone pretreatment prevented AP progression through suppression of miR-26a expression via binding to and degrading PTEN. Western blot analysis demonstrated that rosiglitazone blocked the PI3K/AKT signaling pathway through PTEN. In conclusion, it was determined that rosiglitazone prevented AP by downregulating miR-26a via the PI3K/AKT signaling pathway.
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Affiliation(s)
- Yan Chen
- Department of Emergency, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu 213003, P.R. China
| | - Wei Xiang
- Department of Emergency, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu 213003, P.R. China
| | - Xiang Li
- Department of Emergency, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu 213003, P.R. China
| | - Daming Wang
- Department of Emergency, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu 213003, P.R. China
| | - Chunyan Qian
- Drug Clinical Trial Institution, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu 213003, P.R. China
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Cellular and Molecular Mechanisms of Diabetic Atherosclerosis: Herbal Medicines as a Potential Therapeutic Approach. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:9080869. [PMID: 28883907 PMCID: PMC5572632 DOI: 10.1155/2017/9080869] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 06/30/2017] [Accepted: 07/10/2017] [Indexed: 01/09/2023]
Abstract
An increasing number of patients diagnosed with diabetes mellitus eventually develop severe coronary atherosclerosis disease. Both type 1 and type 2 diabetes mellitus increase the risk of cardiovascular disease associated with atherosclerosis. The cellular and molecular mechanisms affecting the incidence of diabetic atherosclerosis are still unclear, as are appropriate strategies for the prevention and treatment of diabetic atherosclerosis. In this review, we discuss progress in the study of herbs as potential therapeutic agents for diabetic atherosclerosis.
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Mukohda M, Lu KT, Guo DF, Wu J, Keen HL, Liu X, Ketsawatsomkron P, Stump M, Rahmouni K, Quelle FW, Sigmund CD. Hypertension-Causing Mutation in Peroxisome Proliferator-Activated Receptor γ Impairs Nuclear Export of Nuclear Factor-κB p65 in Vascular Smooth Muscle. Hypertension 2017; 70:174-182. [PMID: 28507170 DOI: 10.1161/hypertensionaha.117.09276] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 03/08/2017] [Accepted: 04/08/2017] [Indexed: 12/31/2022]
Abstract
Selective expression of dominant negative (DN) peroxisome proliferator-activated receptor γ (PPARγ) in vascular smooth muscle cells (SMC) results in hypertension, atherosclerosis, and increased nuclear factor-κB (NF-κB) target gene expression. Mesenteric SMC were cultured from mice designed to conditionally express wild-type (WT) or DN-PPARγ in response to Cre recombinase to determine how SMC PPARγ regulates expression of NF-κB target inflammatory genes. SMC-specific overexpression of WT-PPARγ or agonist-induced activation of endogenous PPARγ blunted tumor necrosis factor α (TNF-α)-induced NF-κB target gene expression and activity of an NF-κB-responsive promoter. TNF-α-induced gene expression responses were enhanced by DN-PPARγ in SMC. Although expression of NF-κB p65 was unchanged, nuclear export of p65 was accelerated by WT-PPARγ and prevented by DN-PPARγ in SMC. Leptomycin B, a nuclear export inhibitor, blocked p65 nuclear export and inhibited the anti-inflammatory action of PPARγ. Consistent with a role in facilitating p65 nuclear export, WT-PPARγ coimmunoprecipitated with p65, and WT-PPARγ was also exported from the nucleus after TNF-α treatment. Conversely, DN-PPARγ does not bind to p65 and was retained in the nucleus after TNF-α treatment. Transgenic mice expressing WT-PPARγ or DN-PPARγ specifically in SMC (S-WT or S-DN) were bred with mice expressing luciferase controlled by an NF-κB-responsive promoter to assess effects on NF-κB activity in whole tissue. TNF-α-induced NF-κB activity was decreased in aorta and carotid artery from S-WT but was increased in vessels from S-DN mice. We conclude that SMC PPARγ blunts expression of proinflammatory genes by inhibition of NF-κB activity through a mechanism promoting nuclear export of p65, which is abolished by DN mutation in PPARγ.
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Affiliation(s)
- Masashi Mukohda
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Ko-Ting Lu
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Deng-Fu Guo
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Jing Wu
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Henry L Keen
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Xuebo Liu
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Pimonrat Ketsawatsomkron
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Madeliene Stump
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Kamal Rahmouni
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Frederick W Quelle
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
| | - Curt D Sigmund
- From the Department of Pharmacology and UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa.
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Silva JC, César FA, de Oliveira EM, Turato WM, Tripodi GL, Castilho G, Machado-Lima A, de Las Heras B, Boscá L, Rabello MM, Hernandes MZ, Pitta MGR, Pitta IR, Passarelli M, Rudnicki M, Abdalla DSP. New PPARγ partial agonist improves obesity-induced metabolic alterations and atherosclerosis in LDLr(-/-) mice. Pharmacol Res 2016; 104:49-60. [PMID: 26706782 DOI: 10.1016/j.phrs.2015.12.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Revised: 12/01/2015] [Accepted: 12/08/2015] [Indexed: 02/07/2023]
Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ) regulates multiple pathways involved in the pathogenesis of obesity and atherosclerosis. Here, we evaluated the therapeutic potential of GQ-177, a new thiazolidinedione, on diet-induced obesity and atherosclerosis. The intermolecular interaction between PPARγ and GQ-177 was examined by virtual docking and PPAR activation was determined by reporter gene assay identifying GQ-177 as a partial and selective PPARγ agonist. For the evaluation of biological activity of GQ-177, low-density lipoprotein receptor-deficient (LDLr(-/-)) C57/BL6 mice were fed either a high fat diabetogenic diet (diet-induced obesity), or a high fat atherogenic diet, and treated with vehicle, GQ-177 (20mg/kg/day), pioglitazone (20mg/kg/day, diet-induced obesity model) or rosiglitazone (15mg/kg/day, atherosclerosis model) for 28 days. In diet-induced obesity mice, GQ-177 improved insulin sensitivity and lipid profile, increased plasma adiponectin and GLUT4 mRNA in adipose tissue, without affecting body weight, food consumption, fat accumulation and bone density. Moreover, GQ-177 enhanced hepatic mRNA levels of proteins involved in lipid metabolism. In the atherosclerosis mice, GQ-177 inhibited atherosclerotic lesion progression, increased plasma HDL and mRNA levels of PPARγ and ATP-binding cassette A1 in atherosclerotic lesions. GQ-177 acts as a partial PPARγ agonist that improves obesity-associated insulin resistance and dyslipidemia with atheroprotective effects in LDLr(-/-) mice.
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Affiliation(s)
- Jacqueline C Silva
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Fernanda A César
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Edson M de Oliveira
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Walter M Turato
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Gustavo L Tripodi
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Gabriela Castilho
- Lipids Laboratory (LIM-10), Faculty of Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Adriana Machado-Lima
- Lipids Laboratory (LIM-10), Faculty of Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Beatriz de Las Heras
- Department of Pharmacology, Faculty of Pharmacy, Complutense University of Madrid, Madrid, Spain
| | - Lisardo Boscá
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Madrid, Spain
| | - Marcelo M Rabello
- Department of Pharmaceutical Sciences, Federal University of Pernambuco, Recife, PE, Brazil
| | - Marcelo Z Hernandes
- Department of Pharmaceutical Sciences, Federal University of Pernambuco, Recife, PE, Brazil
| | - Marina G R Pitta
- Core of Therapeutic Innovation, Federal University of Pernambuco, Recife, PE, Brazil
| | - Ivan R Pitta
- Core of Therapeutic Innovation, Federal University of Pernambuco, Recife, PE, Brazil
| | - Marisa Passarelli
- Lipids Laboratory (LIM-10), Faculty of Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Martina Rudnicki
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Dulcineia S P Abdalla
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil.
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Szostak J, Miguet-Alfonsi C, Berthelot A, Laurant P. Training-induced anti-atherosclerotic effects are associated with increased vascular PPARgamma expression in apolipoprotein E-deficient mice. Acta Physiol (Oxf) 2016; 216:221-30. [PMID: 26467845 DOI: 10.1111/apha.12615] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 02/21/2015] [Accepted: 10/06/2015] [Indexed: 12/20/2022]
Abstract
AIM Physical exercise prevents cardiovascular risk and atherosclerosis lesions. However, the molecular aspects are still unknown. Vascular peroxisome proliferator-activated receptors (PPARs) exert anti-atherogenic effects. The aim of this study was to determine whether exercise-induced anti-atherosclerotic effect is associated with change in PPARs vascular expression in apolipoprotein E-deficient (ApoE(-/-) ) mice. METHODS Male ApoE(-/-) mice were fed with a high-fat diet and randomized into two groups: one trained group undergoing swimming training for 3 months and one sedentary group. Sedentary and trained C57BL/6J mice were used as control. mRNA of PPAR-α, PPAR-β/δ and PPAR-γ was measured in aorta by quantitative PCR. mRNA of pro- (TNF-α, IL-1β) and anti-inflammatory (IL-10, IL-1Ra) cytokines was also measured. RESULTS Atherosclerotic lesion size was significantly reduced in trained ApoE(-/-) mice compared to sedentary ones. In contrast, reduction of atherosclerotic lesion size was not observed in trained ApoE(-/-) mice supplied with BADGE, an antagonist of PPAR-γ. Exercise training significantly increased PPAR-γ expression in aorta. PPAR-γ expression was inversely correlated with the atherosclerotic plaque area. Aortic PPAR-α and PPAR-β/δ mRNA expressions were not changed in response to exercise training. Atherosclerosis increased the aortic mRNA expression of TNF-α, IL-1β, IL-10 and IL-1Ra. Exercise training decreased aortic IL-1β mRNA expression in ApoE(-/-) mice, but did not change expression of TNF-α, IL-10 and IL-1Ra. IL-1β mRNA expression was also significantly lower in atherosclerosis lesions from trained ApoE(-/-) compared with those from sedentary ones. CONCLUSIONS Exercise training increases vascular PPAR-γ expression in ApoE(-/-) mice that could potentially underlie training-related beneficial effects on atherosclerosis.
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Affiliation(s)
- J. Szostak
- Sciences Separatives Biologiques et Pharmaceutiques; UFR STAPS/SMP; University of Franche-Comté; Besançon France
| | - C. Miguet-Alfonsi
- Sciences Separatives Biologiques et Pharmaceutiques; UFR STAPS/SMP; University of Franche-Comté; Besançon France
| | - A. Berthelot
- Sciences Separatives Biologiques et Pharmaceutiques; UFR STAPS/SMP; University of Franche-Comté; Besançon France
| | - P. Laurant
- Laboratoire Pharm-Ecologie Cardiovasculaire EA4278; UFRip Sciences Technologie et Santé; UAPV; Avignon France
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Zhao D, Zhu Z, Li D, Xu R, Wang T, Liu K. Pioglitazone Suppresses CXCR7 Expression To Inhibit Human Macrophage Chemotaxis through Peroxisome Proliferator-Activated Receptor γ. Biochemistry 2015; 54:6806-14. [PMID: 26507929 DOI: 10.1021/acs.biochem.5b00847] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cardiovascular disease is the leading cause of morbidity and mortality in patients with type 2 diabetes mellitus (T2DM). Pioglitazone, the widely used thiazolidinedione, is shown to be efficient in the prevention of cardiovascular complications of T2DM. In this study, we report that pioglitazone inhibits CXCR7 expression and thus blocks chemotaxis in differentiated macrophage without perturbing cell viability or macrophage differentiation. In addition, pioglitazone-mediated CXCR7 suppression and chemotaxis inhibition occur via activating peroxisome proliferator-activated receptor γ (PPARγ) but not PPARα in differentiated macrophage. More importantly, pioglitazone therapy-induced PPARγ activation suppresses CXCR7 expression in human carotid atherosclerotic lesions. Collectively, our data demonstrate that pioglitazone suppresses CXCR7 expression to inhibit human macrophage chemotaxis through PPARγ.
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Affiliation(s)
- Duo Zhao
- Department of Cardiovascular Surgery, Second Hospital of Jilin University, Jilin University , Changchun 130041, China
| | - Zhicheng Zhu
- Department of Cardiovascular Surgery, Second Hospital of Jilin University, Jilin University , Changchun 130041, China
| | - Dan Li
- Department of Cardiovascular Surgery, Second Hospital of Jilin University, Jilin University , Changchun 130041, China
| | - Rihao Xu
- Department of Cardiovascular Surgery, Second Hospital of Jilin University, Jilin University , Changchun 130041, China
| | - Tiance Wang
- Department of Cardiovascular Surgery, Second Hospital of Jilin University, Jilin University , Changchun 130041, China
| | - Kexiang Liu
- Department of Cardiovascular Surgery, Second Hospital of Jilin University, Jilin University , Changchun 130041, China
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Brown BE, Kim CHJ, Torpy FR, Bursill CA, McRobb LS, Heather AK, Davies MJ, van Reyk DM. Supplementation with carnosine decreases plasma triglycerides and modulates atherosclerotic plaque composition in diabetic apo E(-/-) mice. Atherosclerosis 2013; 232:403-9. [PMID: 24468155 DOI: 10.1016/j.atherosclerosis.2013.11.068] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 11/08/2013] [Accepted: 11/20/2013] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Carnosine has been shown to modulate triglyceride and glycation levels in cell and animal systems. In this study we investigated whether prolonged supplementation with carnosine inhibits atherosclerosis and markers of lesion stability in hyperglycaemic and hyperlipidaemic mice. METHODS Streptozotocin-induced diabetic apo E(-/-) mice were maintained for 20 weeks, post-induction of diabetes. Half of the animals received carnosine (2g/L) in their drinking water. Diabetes was confirmed by significant increases in blood glucose and glycated haemoglobin, plasma triglyceride and total cholesterol levels, brachiocephalic artery and aortic sinus plaque area; and lower body mass. RESULTS Prolonged carnosine supplementation resulted in a significant (∼20-fold) increase in plasma carnosine levels, and a significant (∼23%) lowering of triglyceride levels in the carnosine-supplemented groups regardless of glycaemic status. Supplementation did not affect glycaemic status, blood cholesterol levels or loss of body mass. In the diabetic mice, carnosine supplementation did not diminish measured plaque area, but reduced the area of plaque occupied by extracellular lipid (∼60%) and increased both macrophage numbers (∼70%) and plaque collagen content (∼50%). The area occupied by α-actin-positive smooth muscle cells was not significantly increased. CONCLUSIONS These data indicate that in a well-established model of diabetes-associated atherosclerosis, prolonged carnosine supplementation enhances plasma levels, and has novel and significant effects on atherosclerotic lesion lipid, collagen and macrophage levels. These data are consistent with greater lesion stability, a key goal in treatment of existing cardiovascular disease. Carnosine supplementation may therefore be of benefit in lowering triglyceride levels and suppressing plaque instability in diabetes-associated atherosclerosis.
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Affiliation(s)
- Bronwyn E Brown
- Free Radical Group, Heart Research Institute, 7 Eliza Street, Newtown, NSW 2042, Australia; Faculty of Medicine, University of Sydney, NSW 2006, Australia.
| | - Christine H J Kim
- Free Radical Group, Heart Research Institute, 7 Eliza Street, Newtown, NSW 2042, Australia.
| | - Fraser R Torpy
- School of the Environment, University of Technology, Sydney, PO Box 123, Broadway, NSW 2007, Australia.
| | - Christina A Bursill
- Immunobiology Group, Heart Research Institute, 7 Eliza Street, Newtown, NSW 2042, Australia.
| | - Lucinda S McRobb
- Gene Regulation Group, Heart Research Institute, 7 Eliza Street, Newtown, NSW 2042, Australia.
| | - Alison K Heather
- Gene Regulation Group, Heart Research Institute, 7 Eliza Street, Newtown, NSW 2042, Australia; School of Medical and Molecular Biosciences, University of Technology, Sydney, PO Box 123, Broadway, NSW 2007, Australia.
| | - Michael J Davies
- Free Radical Group, Heart Research Institute, 7 Eliza Street, Newtown, NSW 2042, Australia; Faculty of Medicine, University of Sydney, NSW 2006, Australia.
| | - David M van Reyk
- School of Medical and Molecular Biosciences, University of Technology, Sydney, PO Box 123, Broadway, NSW 2007, Australia.
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Saremi A, Schwenke DC, Buchanan TA, Hodis HN, Mack WJ, Banerji M, Bray GA, Clement SC, Henry RR, Kitabchi AE, Mudaliar S, Ratner RE, Stentz FB, Musi N, Tripathy D, DeFronzo RA, Reaven PD. Pioglitazone slows progression of atherosclerosis in prediabetes independent of changes in cardiovascular risk factors. Arterioscler Thromb Vasc Biol 2012; 33:393-9. [PMID: 23175674 DOI: 10.1161/atvbaha.112.300346] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE To determine whether changes in standard and novel risk factors during the Actos Now for Prevention of Diabetes trial explained the slower rate of carotid intima media thickness (CIMT) progression with pioglitazone treatment in persons with prediabetes. METHODS AND RESULTS CIMT was measured in 382 participants at the beginning and up to 3 additional times during follow-up of the Actos Now for Prevention of Diabetes trial. During an average follow-up of 2.3 years, the mean unadjusted annual rate of CIMT progression was significantly (P=0.01) lower with pioglitazone treatment (4.76×10(-3) mm/year; 95% CI: 2.39×10(-3)-7.14×10(-3) mm/year) compared with placebo (9.69×10(-3) mm/year; 95% CI: 7.24×10(-3)-12.15×10(-3) mm/year). High-density lipoprotein cholesterol, fasting and 2-hour glucose, HbA(1c), fasting insulin, Matsuda insulin sensitivity index, adiponectin, and plasminogen activator inhibitor-1 levels improved significantly with pioglitazone treatment compared with placebo (P<0.001). However, the effect of pioglitazone on CIMT progression was not attenuated by multiple methods of adjustment for traditional, metabolic, and inflammatory risk factors and concomitant medications, and was independent of changes in risk factors during pioglitazone treatment. CONCLUSIONS Pioglitazone slowed progression of CIMT, independent of improvement in hyperglycemia, insulin resistance, dyslipidemia, and systemic inflammation in prediabetes. These results suggest a possible direct vascular benefit of pioglitazone.
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Affiliation(s)
- Aramesh Saremi
- Phoenix Veterans Affair (VA) Health Care System, Phoenix, AZ, USA
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Kavak S, Ayaz L, Emre M. Effects of rosiglitazone with insulin combination therapy on oxidative stress and lipid profile in left ventricular muscles of diabetic rats. EXPERIMENTAL DIABETES RESEARCH 2012; 2012:905683. [PMID: 22829806 PMCID: PMC3398630 DOI: 10.1155/2012/905683] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 05/01/2012] [Indexed: 11/18/2022]
Abstract
PURPOSE In this study, we tested the hypothesis that rosiglitazone (RSG) with insulin is able to quench oxidative stress initiated by high glucose through prevention of NAD(P)H oxidase activation. METHODS AND MATERIALS Male albino Wistar rats were randomly divided into an untreated control group (C), a diabetic group (D) that was treated with a single intraperitoneal injection of streptozotocin (45 mg kg(-1)), and rosiglitazone group that was treated with RSG twice daily by gavage and insulin once daily by subcutaneous injection (group B). HbA1c and blood glucose levels in the circulation and malondialdehyde and 3-nitrotyrosine levels in left ventricular muscle were measured. RESULT Treatment of D rats with group B resulted in a time-dependent decrease in blood glucose. We found that the lipid profile and HbA1c levels in group B reached the control group D rat values at the end of the treatment period. There was an increase in 3-nitrotyrosine levels in group D compared to group C. Malondialdehyde and 3-nitrotyrosine levels were found to be decreased in group B compared to group D (P < 0.05). CONCLUSION Our data suggests that the treatment of diabetic rats with group B for 8 weeks may decrease the oxidative/nitrosative stress in left ventricular tissue of rats. Thus, in diabetes-related vascular diseases, group B treatment may be cardioprotective.
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Affiliation(s)
- Servet Kavak
- Department of Biophysics, Faculty of Medicine, Yüzüncü Yıl University, 65100 Van, Turkey.
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10
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Duan Y, Chen Y, Hu W, Li X, Yang X, Zhou X, Yin Z, Kong D, Yao Z, Hajjar DP, Liu L, Liu Q, Han J. Peroxisome Proliferator-activated receptor γ activation by ligands and dephosphorylation induces proprotein convertase subtilisin kexin type 9 and low density lipoprotein receptor expression. J Biol Chem 2012; 287:23667-77. [PMID: 22593575 DOI: 10.1074/jbc.m112.350181] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Proprotein convertase subtilisin kexin type 9 (PCSK9) plays an important role in cholesterol homeostasis by enhancing the degradation of LDL receptor (LDLR) protein. Peroxisome proliferator-activated receptor γ (PPARγ) has been shown to be atheroprotective. PPARγ can be activated by ligands and/or dephosphorylation with ERK1/2 inhibitors. The effect of PPARγ on PCSK9 and LDLR expression remains unknown. In this study, we investigated the effects of PPARγ on PCSK9 and LDLR expression. At the cellular levels, PPARγ ligands induced PCSK9 mRNA and protein expression in HepG2 cells. PCSK9 expression was induced by inhibition of ERK1/2 activity but inhibited by ERK1/2 activation. The mutagenic study and promoter activity assay suggested that the induction of PCSK9 expression by ERK1/2 inhibitors was tightly linked to PPARγ dephosphorylation. However, PPARγ activation by ligands or ERK1/2 inhibitors induced hepatic LDLR expression. The promoter assay indicated that the induction of LDLR expression by PPARγ was sterol regulatory element-dependent because PPARγ enhanced sterol regulatory element-binding protein 2 (SREBP2) processing. In vivo, administration of pioglitazone or U0126 alone increased PCSK9 expression in mouse liver but had little effect on PCSK9 secretion. However, the co-treatment of pioglitazone and U0126 enhanced both PCSK9 expression and secretion. Similar to in vitro, the increased PCSK9 expression by pioglitazone and/or U0126 did not result in decreased LDLR expression and function. In contrast, pioglitazone and/or U0126 increased LDLR protein expression and membrane translocation, SREBP2 processing, and CYP7A1 expression in the liver, which led to decreased total and LDL cholesterol levels in serum. Our results indicate that although PPARγ activation increased PCSK9 expression, PPARγ activation induced LDLR and CYP7A1 expression that enhanced LDL cholesterol metabolism.
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Affiliation(s)
- Yajun Duan
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin300071, China
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Sgarra L, Addabbo F, Potenza MA, Montagnani M. Determinants of evolving metabolic and cardiovascular benefit/risk profiles of rosiglitazone therapy during the natural history of diabetes: molecular mechanisms in the context of integrated pathophysiology. Am J Physiol Endocrinol Metab 2012; 302:E1171-82. [PMID: 22374753 DOI: 10.1152/ajpendo.00038.2012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Rosiglitazone is a thiazolidinedione, a synthetic PPARγ receptor agonist with insulin-sensitizing properties that is used as an antidiabetic drug. In addition to improving glycemic control through actions in metabolic target tissues, rosiglitazone has numerous biological actions that impact on cardiovascular homeostasis. Some of these actions are helpful (e.g., improving endothelial function), whereas others are potentially harmful (e.g., promoting fluid retention). Since cardiovascular morbidity and mortality are major endpoints for diabetes, it is essential to understand how the natural history of diabetes alters the net benefits and risks of rosiglitazone therapy. This complex issue is an important determinant of optimal use of rosiglitazone and is critical for understanding cardiovascular safety issues. We give special attention to the effects of rosiglitazone in diabetic patients with stable coronary artery disease and the impact of rosiglitazone actions on atherosclerosis and plaque instability. This provides a rational conceptual framework for predicting evolving benefit/risk profiles that inform optimal use of rosiglitazone in the clinical setting and help explain the results of recent large clinical intervention trials where rosiglitazone had disappointing cardiovascular outcomes. Thus, in this perspective, we describe what is known about the molecular mechanisms of action of rosiglitazone on cardiovascular targets in the context of the evolving pathophysiology of diabetes over its natural history.
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Affiliation(s)
- Luca Sgarra
- Department of Biomedical Sciences and Human Oncology, Medical School, University of Bari, Bari, Italy
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Tiyerili V, Mueller CFH, Becher UM, Czech T, van Eickels M, Daiber A, Nickenig G, Wassmann S. Stimulation of the AT2 receptor reduced atherogenesis in ApoE(-/-)/AT1A(-/-) double knock out mice. J Mol Cell Cardiol 2011; 52:630-7. [PMID: 22230040 DOI: 10.1016/j.yjmcc.2011.12.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 11/21/2011] [Accepted: 12/10/2011] [Indexed: 11/24/2022]
Abstract
AT1 receptor blockers (ARB) and in part ACE inhibitors (ACI) potentially exert beneficial effects on atherogenesis independent of AT1 receptor inhibition. These pleiotropic effects might be related to angiotensin II mediated activation of the AT2 receptor. To analyze this hypothesis we investigated the development of atherosclerosis and the role of ACIs and ARBs in apolipoprotein E-deficient (ApoE(-/-)) mice and in ApoE/AT1A receptor double knockout mice (ApoE(-/-)/AT1A(-/-)). ApoE(-/-) mice and ApoE(-/-)/AT1A(-/-) mice were fed cholesterol-rich diet for 7 weeks. Vascular oxidative stress, endothelial dysfunction, and atherosclerotic lesion formation were evident in ApoE(-/-) mice, but were markedly reduced in ApoE(-/-)/AT1A(-/-) mice. Concomitant treatment of ApoE(-/-)/AT1A(-/-) mice with either telmisartan or ramipril had no additional effect on blood pressure, vascular oxidative stress, AT2 receptor expression, and endothelial function. Remarkably, atherosclerotic lesion formation was increased in ramipril treated ApoE(-/-)/AT1A(-/-) mice compared to untreated ApoE(-/-)/AT1A(-/-) mice whereas pharmacological AT1 receptor inhibition with telmisartan had no additional effect on atherogenesis. Moreover, chronic AT2 receptor inhibition with PD123,319 significantly increased plaque development in ApoE(-/-)/AT1A(-/-) mice. In additional experiments, direct AT2 receptor stimulation reduced atherogenesis in ApoE(-/-)/AT1A(-/-) mice. Taken together, our data demonstrate a relevant antiatherosclerotic role of the AT2 receptor in atherosclerotic mice and provide novel insight in RAS-physiology.
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Affiliation(s)
- Vedat Tiyerili
- Medizinische Klinik und Poliklinik II, University of Bonn, Germany
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Subramanian V, Golledge J, Heywood EB, Bruemmer D, Daugherty A. Regulation of peroxisome proliferator-activated receptor-γ by angiotensin II via transforming growth factor-β1-activated p38 mitogen-activated protein kinase in aortic smooth muscle cells. Arterioscler Thromb Vasc Biol 2011; 32:397-405. [PMID: 22095985 DOI: 10.1161/atvbaha.111.239897] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Peroxisome proliferator-activated receptor-γ (PPARγ) ligands attenuate angiotensin II (Ang II)-induced atherosclerosis through interactions with vascular smooth muscle cell (VSMC)-specific PPARγ in hypercholesterolemic mice. Therefore, the purpose of this study was to determine the mechanism of Ang II-mediated intracellular regulation of PPARγ in VSMCs. METHODS AND RESULTS Incubation of cultured mouse aortic VSMCs with Ang II for 24 hours reduced abundance of PPARγ protein, mRNA, and transcriptional activity (P<0.001). This effect was attenuated by an angiotensin type 1 receptor antagonist, losartan. Ang II-induced PPARγ reduction was dependent on stimulation of transforming growth factor (TGF)-β1 as demonstrated using either a neutralizing antibody or small interfering RNA (siRNA). Ang II-induced TGF-β1 secretion was dependent on epidermal growth factor receptor kinase activation through reactive oxygen species production. Inhibition of p38 mitogen-activated protein kinase by SB203580 or siRNA inhibited both Ang II- and TGF-β1-induced PPARγ reduction. Blockade of TGF-β1 decreased p38 phosphorylation induced by Ang II. siRNA-mediated inhibition of histone deacetylase 3 attenuated p38-mediated reductions in PPARγ abundance. CONCLUSIONS These findings suggest that Ang II decreases PPARγ abundance in cultured VSMCs via an angiotensin type 1 receptor-dependent secretion of TGF-β1 via phosphorylation of p38 mitogen-activated protein kinase and histone deacetylase 3.
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Affiliation(s)
- Venkateswaran Subramanian
- Saha Cardiovascular Research Center, BBSRB, Rm B249, University of Kentucky, Lexington, KY 40536-0509, USA.
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14
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Opposing actions of rosiglitazone and resveratrol on mineralization in human vascular smooth muscle cells. J Mol Cell Cardiol 2011; 51:862-71. [DOI: 10.1016/j.yjmcc.2011.07.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 07/20/2011] [Indexed: 12/29/2022]
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Abstract
Peroxisome proliferator-activated receptor-γ (PPAR-γ), an essential transcriptional mediator of adipogenesis, lipid metabolism, insulin sensitivity, and glucose homeostasis, is increasingly recognized as a key player in inflammatory cells and in cardiovascular diseases (CVD) such as hypertension, cardiac hypertrophy, congestive heart failure, and atherosclerosis. PPAR-γ agonists, the thiazolidinediones (TZDs), increase insulin sensitivity, lower blood glucose, decrease circulating free fatty acids and triglycerides, lower blood pressure, reduce inflammatory markers, and reduce atherosclerosis in insulin-resistant patients and animal models. Human genetic studies on PPAR-γ have revealed that functional changes in this nuclear receptor are associated with CVD. Recent controversial clinical studies raise the question of deleterious action of PPAR-γ agonists on the cardiovascular system. These complex interactions of metabolic responsive factors and cardiovascular disease promise to be important areas of focus for the future.
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Sheng H, Sun H. Synthesis, biology and clinical significance of pentacyclic triterpenes: a multi-target approach to prevention and treatment of metabolic and vascular diseases. Nat Prod Rep 2011; 28:543-93. [DOI: 10.1039/c0np00059k] [Citation(s) in RCA: 211] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Wang N, Yin R, Liu Y, Mao G, Xi F. Role of Peroxisome Proliferator-Activated Receptor-.GAMMA. in Atherosclerosis - An Update -. Circ J 2011; 75:528-35. [DOI: 10.1253/circj.cj-11-0060] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Nanping Wang
- Institute of Cardiovascular Science, Peking University Health Science Center
- Key Laboratory of Molecular Cardiovascular Sciences at Peking University
| | - Ruiying Yin
- Institute of Cardiovascular Science, Peking University Health Science Center
- Key Laboratory of Molecular Cardiovascular Sciences at Peking University
| | - Yan Liu
- Institute of Cardiovascular Science, Peking University Health Science Center
- Key Laboratory of Molecular Cardiovascular Sciences at Peking University
| | - Guangmei Mao
- Institute of Cardiovascular Science, Peking University Health Science Center
- Key Laboratory of Molecular Cardiovascular Sciences at Peking University
| | - Fang Xi
- Institute of Cardiovascular Science, Peking University Health Science Center
- Key Laboratory of Molecular Cardiovascular Sciences at Peking University
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18
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Subramanian V, Golledge J, Ijaz T, Bruemmer D, Daugherty A. Pioglitazone-induced reductions in atherosclerosis occur via smooth muscle cell-specific interaction with PPAR{gamma}. Circ Res 2010; 107:953-8. [PMID: 20798360 DOI: 10.1161/circresaha.110.219089] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Peroxisome proliferator-activated receptor (PPAR)γ agonists attenuate atherosclerosis and abdominal aortic aneurysms (AAAs). PPARγ, a nuclear receptor, is expressed on many cell types including smooth muscle cells (SMCs). OBJECTIVE To determine whether a PPARγ agonist reduces angiotensin II (Ang II)-induced atherosclerosis and AAAs via interaction with SMC-specific PPARγ. METHODS AND RESULTS Low-density lipoprotein receptor (LDLR)(-/-) mice with SMC-specific PPARγ deficiency were developed using PPARγ floxed (PPARγ(f/f)) and SM22 Cre(+) mice. PPARγ(f/f) littermates were generated that did not express Cre (Cre(0/0)) or were hemizygous for Cre (Cre(+/0)). To assess the contribution of SMC-specific PPARγ in ligand-mediated attenuation of Ang II-induced atherosclerosis and AAAs, both male and female Cre(0/0) and Cre(+/0) mice were fed a fat-enriched diet with or without the PPARγ agonist pioglitazone (Pio) (20 mg/kg per day) for 5 weeks. After 1 week of feeding modified diets, mice were infused with Ang II (1000 ng/kg per minute) for 4 weeks. SMC-specific PPARγ deficiency or Pio administration had no effect on plasma cholesterol concentrations. Pio administration attenuated Ang II-increased systolic blood pressure equivalently in both Cre(0/0) and Cre(+/0) groups. SMC-specific PPARγ deficiency increased atherosclerosis in male mice. Pio administration reduced atherosclerosis in only the Cre(0/0) mice, but not in mice with SMC-specific PPARγ deficiency. SMC-specific PPARγ deficiency or Pio administration had no effect on Ang II-induced AAA development. Pio also did not attenuate Ang II-induced monocyte chemoattractant protein-1 production in PPARγ-deficient SMCs. CONCLUSIONS Pio attenuates Ang II-induced atherosclerosis via the interaction with SMC-specific PPARγ, but has no effect on the development of AAAs.
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Affiliation(s)
- Venkateswaran Subramanian
- Saha Cardiovascular Research Center, BBSRB, Room B243, University of Kentucky, Lexington, KY 40536-0509, USA
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Kahn SE, Haffner SM, Viberti G, Herman WH, Lachin JM, Kravitz BG, Yu D, Paul G, Holman RR, Zinman B. Rosiglitazone decreases C-reactive protein to a greater extent relative to glyburide and metformin over 4 years despite greater weight gain: observations from a Diabetes Outcome Progression Trial (ADOPT). Diabetes Care 2010; 33:177-83. [PMID: 19808911 PMCID: PMC2797969 DOI: 10.2337/dc09-1661] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE C-reactive protein (CRP) is closely associated with obesity and cardiovascular disease in both diabetic and nondiabetic populations. In the short term, commonly prescribed antidiabetic agents have different effects on CRP; however, the long-term effects of those agents are unknown. RESEARCH DESIGN AND METHODS In A Diabetes Outcome Progression Trial (ADOPT), we examined the long-term effects of rosiglitazone, glyburide, and metformin on CRP and the relationship among CRP, weight, and glycemic variables in 904 subjects over 4 years. RESULTS Baseline CRP was significantly correlated with homeostasis model assessment of insulin resistance (HOMA-IR), A1C, BMI, waist circumference, and waist-to-hip ratio. CRP reduction was greater in the rosiglitazone group by -47.6% relative to glyburide and by -30.5% relative to metformin at 48 months. Mean weight gain from baseline (at 48 months) was 5.6 kg with rosiglitazone, 1.8 kg with glyburide, and -2.8 kg with metformin. The change in CRP from baseline to 12 months was correlated positively with change in BMI in glyburide (r = 0.18) and metformin (r = 0.20) groups but not in the rosiglitazone (r = -0.05, NS) group. However, there was no longer a significant correlation between change in CRP and change in HOMA-IR, A1C, or waist-to-hip ratio in any of the three treatment groups. CONCLUSIONS Rosiglitazone treatment was associated with durable reductions in CRP independent of changes in insulin sensitivity, A1C, and weight gain. CRP in the glyburide and metformin groups was positively associated with changes in weight, but this was not the case with rosiglitazone.
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Affiliation(s)
- Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, VA Puget Sound Health Care System and University of Washington, Seattle,Washington, USA.
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20
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Negre-Salvayre A, Salvayre R, Augé N, Pamplona R, Portero-Otín M. Hyperglycemia and glycation in diabetic complications. Antioxid Redox Signal 2009; 11:3071-109. [PMID: 19489690 DOI: 10.1089/ars.2009.2484] [Citation(s) in RCA: 265] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Diabetes mellitus is a multifactorial disease, classically influenced by genetic determinants of individual susceptibility and by environmental accelerating factors, such as lifestyle. It is considered a major health concern,as its incidence is increasing at an alarming rate, and the high invalidating effects of its long-term complications affect macro- and microvasculature, heart, kidney, eye, and nerves. Increasing evidence indicates that hyperglycemia is the initiating cause of the tissue damage occurring in diabetes, either through repeated acute changes in cellular glucose metabolism, or through the long-term accumulation of glycated biomolecules and advanced glycation end products (AGEs). AGEs represent a heterogeneous group of chemical products resulting from a nonenzymatic reaction between reducing sugars and proteins, lipids, nucleic acids, or a combination of these.The glycation process (glucose fixation) affects circulating proteins (serum albumin, lipoprotein, insulin, hemoglobin),whereas the formation of AGEs implicates reactive intermediates such as methylglyoxal. AGEs form cross-links on long-lived extracellular matrix proteins or react with their specific receptor RAGE, resulting inoxidative stress and proinflammatory signaling implicated in endothelium dysfunction, arterial stiffening, and microvascular complications. This review summarizes the mechanism of glycation and of AGEs formation and the role of hyperglycemia, AGEs, and oxidative stress in the pathophysiology of diabetic complications.
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Varghese A, Yee MS, Chan CF, Crowe LA, Keenan NG, Johnston DG, Pennell DJ. Effect of rosiglitazone on progression of atherosclerosis: insights using 3D carotid cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2009; 11:24. [PMID: 19635160 PMCID: PMC2726137 DOI: 10.1186/1532-429x-11-24] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Accepted: 07/27/2009] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND There is recent evidence suggesting that rosiglitazone increases death from cardiovascular causes. We investigated the direct effect of this drug on atheroma using 3D carotid cardiovascular magnetic resonance. RESULTS A randomized, placebo-controlled, double-blind study was performed to evaluate the effect of rosiglitazone treatment on carotid atherosclerosis in subjects with type 2 diabetes and coexisting vascular disease or hypertension. The primary endpoint of the study was the change from baseline to 52 weeks of carotid arterial wall volume, reflecting plaque burden, as measured by carotid cardiovascular magnetic resonance. Rosiglitazone or placebo was allocated to 28 and 29 patients respectively. Patients were managed to have equivalent glycemic control over the study period, but in fact the rosiglitazone group lowered their HbA1c by 0.88% relative to placebo (P < 0.001). Most patients received a statin or fibrate as lipid control medication (rosiglitazone 78%, controls 83%). Data are presented as mean +/- SD. At baseline, the carotid arterial wall volume in the placebo group was 1146 +/- 550 mm3 and in the rosiglitazone group was 1354 +/- 532 mm3. After 52 weeks, the respective volumes were 1134 +/- 523 mm3 and 1348 +/- 531 mm3. These changes (-12.1 mm3 and -5.7 mm3 in the placebo and rosiglitazone groups, respectively) were not statistically significant between groups (P = 0.57). CONCLUSION Treatment with rosiglitazone over 1 year had no effect on progression of carotid atheroma in patients with type 2 diabetes mellitus compared to placebo.
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Affiliation(s)
- Anitha Varghese
- National Heart and Lung Institute, Imperial College, London, UK
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK
| | - Michael S Yee
- Division of Medicine, Imperial College, London, UK
- Department of Diabetes, Imperial College Health Care NHS Trust, London, UK
| | - Cheuk F Chan
- National Heart and Lung Institute, Imperial College, London, UK
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK
| | - Lindsey A Crowe
- National Heart and Lung Institute, Imperial College, London, UK
| | - Niall G Keenan
- National Heart and Lung Institute, Imperial College, London, UK
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK
| | - Desmond G Johnston
- Division of Medicine, Imperial College, London, UK
- Department of Diabetes, Imperial College Health Care NHS Trust, London, UK
| | - Dudley J Pennell
- National Heart and Lung Institute, Imperial College, London, UK
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK
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Abstract
Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone-receptor superfamily. Originally cloned in 1990, PPARs were found to be mediators of pharmacologic agents that induce hepatocyte peroxisome proliferation. PPARs also are expressed in cells of the cardiovascular system. PPAR gamma appears to be highly expressed during atherosclerotic lesion formation, suggesting that increased PPAR gamma expression may be a vascular compensatory response. Also, ligand-activated PPAR gamma decreases the inflammatory response in cardiovascular cells, particularly in endothelial cells. PPAR alpha, similar to PPAR gamma, also has pleiotropic effects in the cardiovascular system, including antiinflammatory and antiatherosclerotic properties. PPAR alpha activation inhibits vascular smooth muscle proinflammatory responses, attenuating the development of atherosclerosis. However, PPAR delta overexpression may lead to elevated macrophage inflammation and atherosclerosis. Conversely, PPAR delta ligands are shown to attenuate the pathogenesis of atherosclerosis by improving endothelial cell proliferation and survival while decreasing endothelial cell inflammation and vascular smooth muscle cell proliferation. Furthermore, the administration of PPAR ligands in the form of TZDs and fibrates has been disappointing in terms of markedly reducing cardiovascular events in the clinical setting. Therefore, a better understanding of PPAR-dependent and -independent signaling will provide the foundation for future research on the role of PPARs in human cardiovascular biology.
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Affiliation(s)
- Milton Hamblin
- Cardiovascular Center, Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor, Michigan 48109, USA
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Nakaya H, Summers BD, Nicholson AC, Gotto AM, Hajjar DP, Han J. Atherosclerosis in LDLR-knockout mice is inhibited, but not reversed, by the PPARgamma ligand pioglitazone. THE AMERICAN JOURNAL OF PATHOLOGY 2009; 174:2007-14. [PMID: 19435790 DOI: 10.2353/ajpath.2009.080611] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Thiazolidinediones, a class of drugs for the treatment of type-2 diabetes, are synthetic ligands for peroxisome proliferator-activated receptor-gamma. They have been demonstrated to possess cardioprotective effects in humans and anti-atherogenic properties in animal models. However, the question remains whether a peroxisome proliferator-activated receptor-gamma ligand can reverse the development of atherosclerosis. In this study, we tested the effects of pioglitazone on the development of established atherosclerosis in low-density lipoprotein receptor-null mice. We observed that atherosclerosis in low-density lipoprotein receptor-null mice progressed when mice were fed a high-fat diet. Pioglitazone treatment of atherogenic mice prevented this progression of atherosclerosis from its middle stages of disease, but was not able to reverse it. Withdrawal of the high-fat diet from mice with advanced atherosclerosis did not result in a reduction in lesion sizes. Pioglitazone treatment also had no effect on advanced atherosclerosis. Levels of high density lipoprotein cholesterol correlated inversely with lesion development when pioglitazone was given during lesion progression. However, pioglitazone had no effect on circulating high density lipoprotein levels in mice in which treatment was initiated following 14 weeks on the high-fat diet. These findings have implications for the analysis of therapeutic agents in murine models of atherosclerosis and the use of pioglitazone in patients with established atherosclerosis.
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Affiliation(s)
- Hideaki Nakaya
- Center of Vascular Biology, Department of Pathology, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
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Shen H, Oesterling E, Stromberg A, Toborek M, MacDonald R, Hennig B. Zinc deficiency induces vascular pro-inflammatory parameters associated with NF-kappaB and PPAR signaling. J Am Coll Nutr 2009; 27:577-87. [PMID: 18845708 DOI: 10.1080/07315724.2008.10719741] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Marginal intake of dietary zinc can be associated with increased risk of cardiovascular diseases. In the current study we hypothesized that vascular dysfunction and associated inflammatory events are activated during a zinc deficient state. DESIGN We tested this hypothesis using both vascular endothelial cells and mice lacking the functional LDL-receptor gene. RESULTS Zinc deficiency increased oxidative stress and NF-kappaB DNA binding activity, and induced COX-2 and E-selectin gene expression, as well as monocyte adhesion in cultured endothelial cells. The NF-kappaB inhibitor CAPE significantly reduced the zinc deficiency-induced COX-2 expression, suggesting regulation through NF-kappaB signaling. PPAR can inhibit NF-kappaB signaling, and our previous data have shown that PPAR transactivation activity requires adequate zinc. Zinc deficiency down-regulated PPARalpha expression in cultured endothelial cells. Furthermore, the PPARgamma agonist rosiglitazone was unable to inhibit the adhesion of monocytes to endothelial cells during zinc deficiency, an event which could be reversed by zinc supplementation. Our in vivo data support the importance of PPAR dysregulation during zinc deficiency. For example, rosiglitazone induced inflammatory genes (e.g., MCP-1) only during zinc deficiency, and adequate zinc was required for rosiglitazone to down-regulate pro-inflammatory markers such as iNOS. In addition, rosiglitazone increased IkappaBalpha protein expression only in zinc adequate mice. Finally, plasma data from LDL-R-deficient mice suggest an overall pro-inflammatory environment during zinc deficiency and support the concept that zinc is required for proper anti-inflammatory or protective functions of PPAR. CONCLUSIONS These studies suggest that zinc nutrition can markedly modulate mechanisms of the pathology of inflammatory diseases such as atherosclerosis.
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Affiliation(s)
- Huiyun Shen
- Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536, USA
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25
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Bowes AJ, Khan MI, Shi Y, Robertson L, Werstuck GH. Valproate attenuates accelerated atherosclerosis in hyperglycemic apoE-deficient mice: evidence in support of a role for endoplasmic reticulum stress and glycogen synthase kinase-3 in lesion development and hepatic steatosis. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 174:330-42. [PMID: 19095952 DOI: 10.2353/ajpath.2009.080385] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
We have previously shown that glucosamine promotes endoplasmic reticulum (ER) stress in vascular cells leading to both inflammation and lipid accumulation--the hallmark features of atherosclerosis. Pretreatment with glycogen synthase kinase (GSK)-3 inhibitors protects cultured cells from ER stress-induced dysfunction. Here we evaluate the potential role of GSK-3 on the pro-atherogenic effects of hyperglycemia and ER stress. We show that GSK-3-deficient mouse embryonic fibroblasts do not accumulate unesterified cholesterol under conditions of ER stress. Furthermore, GSK-3 inhibitors, including valproate, attenuate ER stress-induced unesterified cholesterol accumulation in wild-type mouse embryonic fibroblasts. In vivo we show that hyperglycemic apoE-deficient mice have accelerated atherogenesis at the aortic root compared with normoglycemic control mice. Mice fed a diet supplemented with 625 mg/kg valproate have significantly reduced lesion volume relative to nonsupplemented controls. Valproate supplementation has no apparent effect on the plasma levels of either glucose or lipids or on the expression of diagnostic markers of ER stress in the lesion. Significant reductions were observed in total hepatic lipids (>50.4%) and hepatic GSK-3beta activity (>55.8%) in mice fed the valproate diet. In conclusion, dietary supplementation with low levels of valproate significantly attenuates atherogenesis in hyperglycemic apoE-deficient mice. The in vivo anti-atherogenic effects of valproate are consistent with its ability to inhibit GSK-3 and interfere with pro-atherogenic ER stress signaling pathways in vitro.
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Affiliation(s)
- Anna J Bowes
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
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26
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Effects of rosiglitazone on contralateral iliac artery after vascular injury in hypercholesterolemic rabbits. Thromb J 2008; 6:4. [PMID: 18485218 PMCID: PMC2396603 DOI: 10.1186/1477-9560-6-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2007] [Accepted: 05/16/2008] [Indexed: 11/10/2022] Open
Abstract
Background The objective was to evaluate the effects of rosiglitazone on iliac arteries of hypercholesterolemic rabbits undergoing balloon catheter injury in the contralateral iliac arteries. Methods White male rabbits were fed a hypercholesterolemic diet for 6 weeks and divided into two groups as follows: rosiglitazone group, 14 rabbits treated with rosiglitazone (3 mg/Kg body weight/day) during 6 weeks; and control group, 18 rabbits without rosiglitazone treatment. All animals underwent balloon catheter injury of the right iliac artery on the fourteenth day of the experiment. Results There was no significant difference in intima/media layer area ratio between the control group and the rosiglitazone group. Rosiglitazone did not reduce the probability of lesions types I, II, or III (72.73% vs. 92.31%; p = 0.30) and types IV or V (27.27% vs. 7.69%; p = 0.30). There were no differences in the extent of collagen type I and III deposition or in the percentage of animals with macrophages in the intima layer. The percentage of rabbits with smooth muscle cells in the intima layer was higher in rosiglitazone group (p = 0.011). Conclusion These findings demonstrate that rosiglitazone given for 6 weeks did not prevent atherogenesis at a vessel distant from the injury site.
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Davidson M, Meyer PM, Haffner S, Feinstein S, D'Agostino R, Kondos GT, Perez A, Chen Z, Mazzone T. Increased high-density lipoprotein cholesterol predicts the pioglitazone-mediated reduction of carotid intima-media thickness progression in patients with type 2 diabetes mellitus. Circulation 2008; 117:2123-30. [PMID: 18413496 DOI: 10.1161/circulationaha.107.746610] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Measurement of carotid intima-media thickness (CIMT) has been validated as a measure of atherosclerosis and as a predictor of future cardiovascular events. Compared with glimepiride, pioglitazone has been shown to slow the progression of atherosclerosis measured by CIMT in patients with type 2 diabetes mellitus. METHODS AND RESULTS We evaluated individual cardiovascular risk factors as predictors of the change in CIMT produced by pioglitazone treatment by determining whether their addition to a baseline model resulted in loss of significance for the treatment effect on CIMT. Pioglitazone treatment led to improvement in levels of multiple cardiovascular risk markers, including high-sensitivity C-reactive protein, apolipoprotein B, apolipoprotein A1, high-density lipoprotein (HDL) cholesterol, triglyceride, insulin, and free fatty acid. At 24 weeks, there were significant differences in HDL cholesterol, triglyceride, total cholesterol, low-density lipoprotein cholesterol, insulin, body mass index, hip circumference, and high-sensitivity C-reactive protein between the pioglitazone and glimepiride treatment groups. After adjustment for 24-week on-treatment values of cardiovascular risk factors, only inclusion of the changes in HDL cholesterol and insulin significantly impacted the magnitude and significance of the treatment effect on CIMT. Furthermore, irrespective of treatment assignment, increased HDL cholesterol at 24 weeks was a significant predictor of reduced CIMT progression at 72 weeks. CONCLUSIONS The beneficial effect of pioglitazone on HDL cholesterol at 24 weeks predicted its beneficial effect for reducing CIMT progression at 72 weeks. Changes in HDL cholesterol at 24 weeks, irrespective of treatment, predicted less progression of CIMT at 72 weeks. These results suggest that suppression of atherosclerosis with pioglitazone therapy is linked to its ability to raise HDL cholesterol.
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Affiliation(s)
- Michael Davidson
- Pritzker School of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
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Abstract
Although hyperlipidemia clearly plays a role in developing cardiovascular disease, the 10% of the population with the highest LDL levels account for only 20% of cardiovascular disease events. Thus, in order to significantly reduce the burden of cardiovascular disease, subjects with only modest dyslipidemia need to be treated with lipid-lowering therapy. Current guidelines have recommended aggressive lipid-lowering therapy in subjects at high risk of cardiovascular disease. The rationale behind this and treatment options to achieve target lipid goals are discussed.
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Affiliation(s)
- Lisa R Tannock
- Division of Endocrinology and Molecular Medicine, University of Kentucky, and, Veterans Affairs Medical Center, Lexington, Kentucky 40502, USA.
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Rohatgi A, McGuire DK. Effects of the thiazolidinedione medications on micro- and macrovascular complications in patients with diabetes--update 2008. Cardiovasc Drugs Ther 2008; 22:233-40. [PMID: 18373186 DOI: 10.1007/s10557-008-6093-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Accepted: 01/24/2008] [Indexed: 01/07/2023]
Abstract
INTRODUCTION The thiazolidinedione (TZD) drugs, including pioglitazone (Actos) and rosiglitazone (Avandia), are commonly prescribed in patients with type 2 diabetes mellitus (T2DM), largely due to their favorable effects on hyperglycemia, insulin sensitivity, and cardiometabolic profile. However, the data are sparse assessing the effects of TZDs on micro- and macrovascular disease risk. DISCUSSION Although no studies have been published on microvascular clinical outcomes, both TZDs significantly reduce the urine albumin-to-creatinine ratio. TZDs have consistently been associated with favorable effects on atherosclerosis and cardiovascular disease (CVD) risk. Only one study has been published to date specifically designed to assess the effects of a TZD (pioglitazone) on macrovascular outcomes, the PROactive trial. In this trial, pioglitazone versus placebo was associated with a non-significant 10% reduction in the combined primary endpoint of mortality, coronary and peripheral vascular events, and revascularizations. No individual trial has been published specifically assessing the CVD effects of rosiglitazone, but several meta-analyses and a published interim report from an ongoing trial (RECORD) point to safety concerns regarding rosiglitazone use and the risk of myocardial infarctions (MI), leading to amplified warnings in the product labeling for rosiglitazone to reflect these concerns. CONCLUSION All published trials and meta-analyses of TZDs have consistently shown increased risk of heart failure (HF) with both TZDs, though the actual placebo-subtracted incidence of HF is low (<0.5% per year). The initiation of either TZD is contraindicated in patients with NHYA class III or IV HF, and cautions exist for their use in any patient with heart failure. Much uncertainty remains regarding the aggregate CVD effects of the TZDs, and several trials are presently underway to further address these issues.
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Affiliation(s)
- Anand Rohatgi
- Cardiovascular Division, University of Texas Southwestern Medical Center, Dallas, TX 75235-9047, USA
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Duan SZ, Usher MG, Mortensen RM. Peroxisome Proliferator-Activated Receptor-γ–Mediated Effects in the Vasculature. Circ Res 2008; 102:283-94. [DOI: 10.1161/circresaha.107.164384] [Citation(s) in RCA: 216] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Peroxisome proliferator-activated receptor (PPAR)-γ is a nuclear receptor and transcription factor in the steroid superfamily. PPAR-γ agonists, the thiazolidinediones, are clinically used to treat type 2 diabetes. In addition to its function in adipogenesis and increasing insulin sensitivity, PPAR-γ also plays critical roles in the vasculature. In vascular endothelial cells, PPAR-γ activation inhibits endothelial inflammation by suppressing inflammatory gene expression and therefore improves endothelial dysfunction. In vascular smooth muscle cells, PPAR-γ activation inhibits proliferation and migration and promotes apoptosis. In macrophages, PPAR-γ activation suppresses inflammation by regulating gene expression and increases cholesterol uptake and efflux. A recurring theme in many cell types is the modulation of the innate immunity system particularly through altering the activity of the nuclear factor κB. This system is likely to be even more prominent in modulating disease in vascular cells. The effects of PPAR-γ in the vascular cells translate into the beneficial function of this transcription factor in vascular disorders, including hypertension and atherosclerosis. Both human genetic studies and animal studies using transgenic mice have demonstrated the importance of PPAR-γ in these disorders. However, recent clinical studies have raised significant concerns about the cardiovascular side effects of thiazolidinediones, particularly rosiglitazone. Weighing the potential benefit and harm of PPAR-γ activation and exploring the functional mechanisms may provide a balanced view on the clinical use of these compounds and new approaches to the future therapeutics of vascular disorders associated with diabetes.
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Affiliation(s)
- Sheng Zhong Duan
- From the Departments of Molecular and Integrative Physiology (S.Z.D., M.G.U., R.M.M.), Pharmacology (R.M.M.), and Internal Medicine (R.M.M.), Metabolism Endocrinology and Diabetes Division, University of Michigan Medical School, Ann Arbor
| | - Michael G. Usher
- From the Departments of Molecular and Integrative Physiology (S.Z.D., M.G.U., R.M.M.), Pharmacology (R.M.M.), and Internal Medicine (R.M.M.), Metabolism Endocrinology and Diabetes Division, University of Michigan Medical School, Ann Arbor
| | - Richard M. Mortensen
- From the Departments of Molecular and Integrative Physiology (S.Z.D., M.G.U., R.M.M.), Pharmacology (R.M.M.), and Internal Medicine (R.M.M.), Metabolism Endocrinology and Diabetes Division, University of Michigan Medical School, Ann Arbor
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Zadelaar S, Kleemann R, Verschuren L, de Vries-Van der Weij J, van der Hoorn J, Princen HM, Kooistra T. Mouse models for atherosclerosis and pharmaceutical modifiers. Arterioscler Thromb Vasc Biol 2007; 27:1706-21. [PMID: 17541027 DOI: 10.1161/atvbaha.107.142570] [Citation(s) in RCA: 405] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Atherosclerosis is a multifactorial highly-complex disease with numerous etiologies that work synergistically to promote lesion development. The ability to develop preventive and ameliorative treatments will depend on animal models that mimic the human subject metabolically and pathophysiologically and will develop lesions comparable to those in humans. The mouse is the most useful, economic, and valid model for studying atherosclerosis and exploring effective therapeutic approaches. Among the most widely used mouse models for atherosclerosis are apolipoprotein E-deficient (ApoE-/-) and LDL receptor-deficient (LDLr-/-) mice. An up-and-coming model is the ApoE*3Leiden (E3L) transgenic mouse. Here, we review studies that have explored how and to what extent these mice respond to compounds directed at treatment of the risk factors hypercholesterolemia, hypertriglyceridemia, hypertension, and inflammation. An important outcome of this survey is that the different models used may differ markedly from one another in their response to a specific experimental manipulation. The choice of a model is therefore of critical importance and should take into account the risk factor to be studied and the working spectrum of the compounds tested.
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Affiliation(s)
- Susanne Zadelaar
- TNO Quality of Life, Gaubius Laboratory, Department of Biosciences, P.O. Box 2215, 2301 CE Leiden, The Netherlands
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Abstract
PURPOSE OF REVIEW Although the thiazolidinediones were introduced for the treatment of hyperglycemia in type 2 diabetes, it became quickly apparent that these agents modulated many pathways related to vascular physiology and pathophysiology. Given the fact that cardiovascular disease is the leading cause of death in diabetes, it has become important to know whether these agents have vasculoprotective effects and if so whether these are associated with the prevention of cardiovascular disease. RECENT FINDINGS The thiazolidinedione class improves endothelial vasomotion, inhibits inflammatory and procoagulant processes and has powerful antiproliferative and antioxidant effects. Experimentally these agents retard atherosclerosis development in predisposed animals. Clinical studies demonstrate that they increase HDL cholesterol and LDL size, and may lower triglyceride levels. They modestly lower blood pressure, reduce microalbuminuria, arterial stiffness and reduce carotid wall thickening. These effects are generally independent of glucose lowering and in many instances have been shown to occur in nondiabetic subjects. A single clinical endpoint intervention trial of add-on pioglitazone treatment in type 2 diabetic patients with cardiovascular disease suggested on secondary analyses that the agent reduced cardiovascular events. SUMMARY The weight of the experimental, subclinical and clinical assessments of the effects of these agents supports the contention that they are vasculoprotective. In the final analysis their use in clinical practice to prevent cardiovascular disease will mostly depend on whether clinical trials consistently demonstrate that they reduced cardiovascular events.
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Affiliation(s)
- Ronald B Goldberg
- Division of Endocrinology, Diabetes and Metabolism, Diabetes Research Institute, The University of Miami Miller School of Medicine, Miami, Florida 33136, USA.
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Stocker DJ, Taylor AJ, Langley RW, Jezior MR, Vigersky RA. A randomized trial of the effects of rosiglitazone and metformin on inflammation and subclinical atherosclerosis in patients with type 2 diabetes. Am Heart J 2007; 153:445.e1-6. [PMID: 17307426 DOI: 10.1016/j.ahj.2006.11.005] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Accepted: 11/11/2006] [Indexed: 11/23/2022]
Abstract
BACKGROUND Metformin and rosiglitazone both improve glycemic control in type 2 diabetes mellitus, however may possess different anti-inflammatory and anti-atherosclerotic properties. We investigated the effects of these medications on high-sensitivity C-reactive protein (hsCRP) and carotid artery intima-media thickness (CIMT) to determine their relative potential to reduce cardiovascular risk independent of their antihyperglycemic actions. METHODS Ninety-two subjects with suboptimally controlled diabetes mellitus (hemoglobin A1c [HbA1c] >7.0%) were assigned to therapy with either rosiglitazone 4 mg once daily or metformin 850 mg twice daily for 24 weeks. The primary end point was the change in hsCRP after 24 weeks. The change in CIMT was prespecified as a secondary end point. RESULTS Metformin and rosiglitazone treatment led to similar significant improvements in glycemic control (HbA1c -1.08% in the rosiglitazone group and -1.18% in the metformin group, P = nonsignificant). High-sensitivity C-reactive protein levels decreased by an average of 68% in the rosiglitazone group (5.99 +/- 0.88 to 1.91 +/- 0.28 mg/L, P < .001), compared with a nonsignificant 4% reduction in hsCRP with metformin (5.69 +/- 0.83 to 5.46 +/- 0.92 mg/L; P = nonsignificant). Maximal CIMT progressed in the metformin group (+0.084 +/- 0.038 mm), whereas regression of maximal CIMT was observed in the rosiglitazone group (-0.037 +/- 0.031 mm; P = .02 for the between group comparison). Similar changes were observed for mean CIMT. The change in hsCRP and maximal CIMT were related in a multivariable model controlling for changes in HbA1c and lipid parameters (r = .31; P = .01). CONCLUSIONS Rosiglitazone, compared to metformin, induced a prompt and profound reduction in hsCRP levels independent of its effect on glycemia. This change was associated with regression of CIMT after 24 weeks.
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Affiliation(s)
- Derek J Stocker
- Endocrine, Diabetes, and Metabolism Service, Department of Medicine, Walter Reed Army Medical Center, Washington, DC 20307, USA
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Pakala R, Dilcher C, Baffour R, Hellinga D, Seabron R, Joner M, Kolodgie F, Virmani R, Waksman R. Peroxisome Proliferator-Activated Receptor γ Ligand Pioglitazone Alters Neointimal Composition in a Balloon-Denuded and Radiated Hypercholesterolemic Rabbit. J Cardiovasc Pharmacol 2006; 48:299-305. [PMID: 17204909 DOI: 10.1097/01.fjc.0000249891.40714.2a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Peroxisome proliferator-activated receptor (PPAR)-gamma activation suppresses inflammatory response, monocyte recruitment, and vascular cell proliferation. Because inflammation, deregulated growth, and migration of monocytes and vascular smooth muscle cells (VSMC) play important roles in the development of neointima, we tested the effect of pioglitazone, a high-affinity ligand, for PPAR-gamma on neointima formation in the iliac arteries of a balloon-denuded and radiated hypercholesterolemic rabbit. Rabbits were fed a 1.0% cholesterol diet for 7 days followed by denudation of endothelial layer and continued on a 0.15% cholesterol diet. On day 32, animals were divided into 2 groups. One group received a 0.15% cholesterol diet (n = 7) and the other group received a 0.15% cholesterol diet supplemented with 400 mg of pioglitazone per kilogram. On day 35, the balloon-denuded area was radiated. Four weeks after radiation, animals were sacrificed and arterial segments were processed for morphometry and immunohistochemistry. Data analysis showed that the pioglitazone group had smaller neointima (0.85 +/- 0.36 vs. 1.41 +/- 0.56, P < 0.05), with more cells positive for VSMC (23.07 +/- 6.16 vs. 18.33 +/- 5.19, P = 0.04), less for monocytes (16.01 +/- 5.33 vs. 21.29 +/- 4.33, P < 0.05), and fewer cells expressing metalloproteinase (MMP)-1 and MMP-9 (3.69 +/- 0.47 vs. 4.82 +/- 0.93, P < 0.05 and 3.24 +/- 0.71 vs. 4.29 +/- 0.74, P < 0.05, respectively). Pioglitazone reduced neointimal area and modified its composition in a balloon-denuded and radiated hypercholesterolemic rabbit model.
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Affiliation(s)
- Rajbabu Pakala
- Cardiovascular Research Institute, Washington Hospital Center, Washington, DC, USA
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Calkin AC, Allen TJ. Diabetes mellitus-associated atherosclerosis: mechanisms involved and potential for pharmacological invention. Am J Cardiovasc Drugs 2006; 6:15-40. [PMID: 16489846 DOI: 10.2165/00129784-200606010-00003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
While diabetes mellitus is most often associated with hypertension, dyslipidemia, and obesity, these factors do not fully account for the increased burden of cardiovascular disease in patients with the disease. This strengthens the need for comprehensive studies investigating the underlying mechanisms mediating diabetic cardiovascular disease and, more specifically, diabetes-associated atherosclerosis. In addition to the recognized metabolic abnormalities associated with diabetes mellitus, upregulation of putative pathological pathways such as advanced glycation end products, the renin-angiotensin system, oxidative stress, and increased expression of growth factors and cytokines have been shown to play a causal role in atherosclerotic plaque formation and may explain the increased risk of macrovascular complications. This review discusses the methods used to assess the development of atherosclerosis in the clinic as well as addressing novel biomarkers of atherosclerosis, such as low-density lipoprotein receptor-1. Experimental models of diabetes-associated atherosclerosis are discussed, such as the streptozocin-induced diabetic apolipoprotein E knockout mouse. Results of major clinical trials with inhibitors of putative atherosclerotic pathways are presented. Other topics covered include the role of HMG-CoA reductase inhibitors and fibric acid derivatives with respect to their lipid-altering ability, as well as their emerging pleiotropic anti-atherogenic actions; the effect of inhibiting the renin-angiotensin system by either ACE inhibition or angiotensin II receptor antagonism; the effect of glycemic control and, in particular, the promising role of thiazolidinediones with respect to their direct anti-atherogenic actions; and newly emerging mediators of diabetes-associated atherosclerosis, such as advanced glycation end products, vascular endothelial growth factor and platelet-derived growth factor. Overall, this review aims to highlight the observation that various pathways, both independently and in concert, appear to contribute toward the pathology of diabetes-associated atherosclerosis. Furthermore, it reflects the need for combination therapy to combat this disease.
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Affiliation(s)
- Anna C Calkin
- JDRF Danielle Alberti Memorial Centre for Diabetes Complications, Baker Heart Research Institute, Melbourne, Victoria, Australia.
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Pfützner A, Schöndorf T, Seidel D, Winkler K, Matthaei S, Hamann A, Forst T. Impact of rosiglitazone on beta-cell function, insulin resistance, and adiponectin concentrations: results from a double-blind oral combination study with glimepiride. Metabolism 2006; 55:20-5. [PMID: 16324915 DOI: 10.1016/j.metabol.2005.06.021] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2005] [Accepted: 06/19/2005] [Indexed: 12/22/2022]
Abstract
Addition of rosiglitazone to sulfonylurea has been shown to improve glycemic control in patients with type 2 diabetes previously treated with sulfonylurea monotherapy alone. This investigation was performed to assess the specific impact of rosiglitazone on insulin resistance, beta-cell function, cardiovascular risk markers, and adiponectin secretion in this treatment concept. One hundred two patients from a double-blind, 3-arm comparator trial (group 0, glimepiride + placebo, n = 30; group 4, glimepiride + 4 mg rosiglitazone, n = 31; group 8, glimepiride + 8 mg rosiglitazone, n = 41; 48 women, 54 men; age [mean +/- SD], 62.8 +/- 9.1 years; body mass index, 28.7 +/- 4.5 kg/m2; diabetes duration, 6.4 +/- 4.8 years; HbA1c, 8.1% +/- 1.5%) were analyzed after 0 and 16 weeks of treatment. Observation parameters were HbA1c, glucose, homeostasis model assessment for insulin resistance score, insulin, intact proinsulin, and adiponectin. Insulin resistance was defined by elevated intact proinsulin values or homeostasis model assessment for insulin resistance score of more than 2. All parameters were comparable in the 3 groups at baseline. Substantial and significant dose-dependent improvements were observed after addition of rosiglitazone for fasting glucose (group 0, -9 +/- 48 mg/dL; group 4, -38 +/- 47 mg/dL; group 8, -46 +/- 53 mg/dL), HbA1c (-0.1% +/- 0.7%, -1.1% +/- 1.2%, -1.3% +/- 1.2%), insulin (1.4 +/- 6.2, -1.2 +/- 5.3, -3.7 +/- 9.9 microU/mL), intact proinsulin (1.6 +/- 7.1, -2.0 +/- 4.6, -3.1 +/- 6.1 pmol/L), and high-sensitivity C-reactive protein (0.2 +/- 2.6, -1.7 +/- 3.5, -2.1 +/- 3.5 mg/L). After adjustment for changes in body weight, significant increases in adiponectin were detected with rosiglitazone, whereas glimepiride alone did not induce a comparable effect (-0.5 +/- 5.8, 8.8 +/- 22.9, 14.3 +/- 19.9 mg/L). The number of insulin-resistant patients decreased in both rosiglitazone treatment groups, whereas no change was seen with glimepiride alone. Next to the reported effects on glucose control, rosiglitazone provided an additional beneficial effect on insulin resistance, beta-cell function, and cardiovascular risk markers. In conclusion, our short-term investigation of rosiglitazone action provides further experimental support for the rationale of combining rosiglitazone with sulfonylurea drugs in patients with type 2 diabetes.
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Affiliation(s)
- Andreas Pfützner
- IKFE Institute for Clinical Research and Development, Mainz, Germany.
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Abstract
Our knowledge and understanding of the role played by peroxisome proliferator-activated gamma receptors in physiology and pathophysiology has expanded dramatically over the past 5 years. Originally described as having important functions in adipogenesis and glucose homeostasis, their pharmacologic agonists, the thiazolidinediones, were introduced as antihyperglycemic, insulin-sensitizing agents for the management of type 2 diabetes mellitus. However, it was to some degree inevitable that the thiazolidinediones would be rapidly recognized as having vasculoprotective properties beyond glycemic control that might also be beneficial. First, diabetic complications are vascular in nature, the earliest feature of these is endothelial dysfunction. Second, it is being increasingly appreciated that these complications develop through inflammatory and procoagulant pathways in which increased oxidative stress is considered a major etiologic mechanism, and which are closely linked to the presence of insulin resistance, visceral obesity, and hyperglycemia. Early appreciation that the thiazolidinediones have antioxidant, anti-inflammatory, anti-procoagulant, and antiproliferative properties in addition to their insulin-sensitizing, anti-lipotoxic properties created a marriage of investigative pathways that has not only led to a very large body of literature on the pleiotropic effects of thiazolidinediones, but also to the development of new understandings of the connections between insulin resistance, obesity, and hyperglycemia and the onset of vascular disease. Understandably, most of the focus has been directed at the macrovascular complications of diabetes, since these are the major causes of morbidity and mortality in this population. However, there is evidence that these agents may have benefits for the microvascular complications as well, and their potential role for cardiovascular disease prevention in non-diabetic patients with the metabolic syndrome is a logical extension of the work performed in diabetes. The recently reported results of the effects of pioglitazone versus placebo on cardiovascular events in patients with type 2 diabetes support the contention that these agents have vasculoprotective effects.
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Affiliation(s)
- Kathryn Reynolds
- Diabetes Research Institute, The University of Miami Miller School of Medicine, Miami, Florida, USA
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Bellinger DA, Merricks EP, Nichols TC. Swine Models of Type 2 Diabetes Mellitus: Insulin Resistance, Glucose Tolerance, and Cardiovascular Complications. ILAR J 2006; 47:243-58. [PMID: 16804199 DOI: 10.1093/ilar.47.3.243] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Dwight A Bellinger
- Department of Pathology and Laboratory Medicine and Division of Laboratory Animal Medicine, University of North Carolina, School of Medicine, Chapel Hill, NC, USA
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Cao W, Collins QF, Becker TC, Robidoux J, Lupo EG, Xiong Y, Daniel KW, Floering L, Collins S. p38 Mitogen-activated protein kinase plays a stimulatory role in hepatic gluconeogenesis. J Biol Chem 2005; 280:42731-7. [PMID: 16272151 DOI: 10.1074/jbc.m506223200] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Hepatic gluconeogenesis is essential for maintaining blood glucose levels during fasting and is the major contributor to postprandial and fasting hyperglycemia in diabetes. Gluconeogenesis is a classic cAMP/protein kinase A-dependent process initiated by glucagon, which is elevated in the blood during fasting and in diabetes. In this study, we have shown that p38 mitogen-activated protein kinase (p38) was activated in liver by fasting and in primary hepatocytes by glucagon or forskolin. Fasting plasma glucose levels were reduced upon blockade of p38 with either a chemical inhibitor or small interference RNA in mice. In examining the mechanism, inhibition of p38 suppressed gluconeogenesis in liver, along with expression of key gluconeogenic genes, including phosphoenolpyruvate carboxykinase and glucose-6-phosphatase. Peroxisome proliferator-activated receptor gamma coactivator 1alpha and cAMP-response element-binding protein have been shown to be important mediators of hepatic gluconeogenesis. We have shown that inhibition of p38 prevented transcription of the PPARgamma coactivator 1alpha gene as well as phosphorylation of cAMP-response element-binding protein. Together, our results from in vitro and in vivo studies define a model in which cAMP-dependent activation of genes involved in gluconeogenesis is dependent upon the p38 pathway, thus adding a new player to our evolving understanding of this physiology.
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Affiliation(s)
- Wenhong Cao
- Endocrine Biology Program, CIIT Centers for Health Research, Research Triangle Park, North Carolina 27709, USA.
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Graham TL, Mookherjee C, Suckling KE, Palmer CNA, Patel L. The PPARdelta agonist GW0742X reduces atherosclerosis in LDLR(-/-) mice. Atherosclerosis 2005; 181:29-37. [PMID: 15939051 DOI: 10.1016/j.atherosclerosis.2004.12.028] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Revised: 11/19/2004] [Accepted: 12/03/2004] [Indexed: 01/22/2023]
Abstract
Several lines of evidence suggest a biological role for peroxisome proliferator-activated receptor (PPARdelta) in the pathogenesis of atherosclerosis. Administration of synthetic PPARdelta agonists to obese rhesus monkeys elevates serum high-density lipoprotein (HDL) cholesterol as a result of increased reverse cholesterol transport whilst in vitro studies have suggested a role for PPARdelta in lipid uptake into macrophages. Recent studies have found that PPARdelta depletion from macrophages in LDL receptor (LDLR(-/-)) mice decreases lesion area via modulation of the inflammatory status of the macrophage, an effect also seen on pharmacological activation of PPARdelta in vitro. We demonstrate here that the PPARdelta agonist, GW0742X has potent anti-atherogenic activity in the LDLR(-/-) mouse, decreasing lesion area by up to 50%. Administration of GW0742X had no effect on total cholesterol, HDL or LDL cholesterol and modest effects on very low-density lipoprotein (VLDL). Treatment with GW0742X resulted in decreased expression of monocyte chemoattractant protein 1 (MCP-1) and intracellular adhesion moleculae 1 (ICAM-1) in the aortae of treated mice. In addition, GW0742X decreased tumour necrosis factor-alpha (TNFalpha) expression in peritoneal macrophages, aortae and adipose tissue in comparison with control animals. Changes in gene expression were reflected in decreased plasma levels of MCP-1. These observations support an atheroprotective effect of PPARdelta agonists in vivo.
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Affiliation(s)
- Tracey L Graham
- Biomedical Research Centre, Ninewells Hospital and Medical School, University of Dundee, Scotland, UK
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Calkin AC, Forbes JM, Smith CM, Lassila M, Cooper ME, Jandeleit-Dahm KA, Allen TJ. Rosiglitazone Attenuates Atherosclerosis in a Model of Insulin Insufficiency Independent of Its Metabolic Effects. Arterioscler Thromb Vasc Biol 2005; 25:1903-9. [PMID: 16020748 DOI: 10.1161/01.atv.0000177813.99577.6b] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objectives—
Recent studies have demonstrated a role for thiazolidinediones in attenuating atherosclerosis. However, these studies were performed in insulin-resistant animal models in association with reductions in insulin and glucose levels. To assess the vascular effects of thiazolidinediones, independent of their metabolic effects, we observed the effect of rosiglitazone on diabetes-associated atherosclerosis in a model of insulin insufficiency.
Methods and Results—
Control and diabetic apolipoprotein E–deficient mice received rosiglitazone or placebo. Diabetic mice demonstrated a 3-fold increase in plaque area, which was attenuated by rosiglitazone. There was no significant difference in glucose, insulin, or cholesterol levels between treated and untreated diabetic animals. Rosiglitazone attenuated the increase in superoxide production observed in diabetic mice. A 4-fold increase in the reverse cholesterol transport marker ABCA1 was observed in treated diabetic mice. Rosiglitazone reduced angiotensin II receptor gene expression in control and diabetic mice, and macrophage accumulation was increased in diabetic mice compared with controls and was attenuated by rosiglitazone.
Conclusions—
These findings suggest peroxisome proliferator-activated receptor-γ ligands such as rosiglitazone confer vascular protection independent of their effects on metabolic control. These antiatherosclerotic effects may have important clinical ramifications not only in insulin resistance/type 2 diabetes and also in type 1 diabetes.
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Affiliation(s)
- Anna C Calkin
- JDRF Danielle Alberti Centre for Diabetes Complications, Vascular Division, Wynn Domain, Baker Heart Research Institute, Melbourne 8008, Australia.
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Hennuyer N, Tailleux A, Torpier G, Mezdour H, Fruchart JC, Staels B, Fiévet C. PPARα, but not PPARγ, Activators Decrease Macrophage-Laden Atherosclerotic Lesions in a Nondiabetic Mouse Model of Mixed Dyslipidemia. Arterioscler Thromb Vasc Biol 2005; 25:1897-902. [PMID: 15994444 DOI: 10.1161/01.atv.0000175756.56818.ee] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Peroxisome proliferator-activated receptor (PPAR) alpha and gamma are nuclear receptors that may modulate atherogenesis, not only by correcting metabolic disorders predisposing to atherosclerosis but also by directly acting at the level of the vascular wall. The accumulation of lipid-laden macrophages in the arterial wall is an early pivotal event participating in the initiation and promotion of atherosclerotic lesion formation. Because PPARalpha and gamma modulate macrophage gene expression and cellular function, it has been suggested that their ligands may modulate atherosclerosis development via direct effects on macrophages. In this report, we investigated the effect of a PPARalpha ligand (fenofibrate) and 2 PPARgamma ligands (rosiglitazone and pioglitazone) on atherogenesis in a dyslipidemic nondiabetic murine model that develops essentially macrophage-laden lesions. METHODS AND RESULTS Mice were fed a Western diet supplemented or not with fenofibrate (100 mpk), rosiglitazone (10 mpk), or pioglitazone (40 mpk) for 10 weeks. Atherosclerotic lesions together with metabolic parameters were measured after treatment. Fenofibrate treatment significantly improved lipoprotein metabolism toward a less atherogenic phenotype but did not affect insulin sensitivity. Contrarily, rosiglitazone and pioglitazone improved glucose homeostasis, whereas they did not improve lipoprotein metabolism. Fenofibrate treatment significantly decreased the accumulation of lipids and macrophages in the aortic sinus. However, surprisingly, neither rosiglitazone nor pioglitazone had an effect on lesion lipid accumulation or macrophage content. CONCLUSIONS These results indicate that in a dyslipidemic nondiabetic murine model, PPARalpha, but not PPARgamma, activators protect against macrophage foam cell formation.
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Affiliation(s)
- Nathalie Hennuyer
- INSERM U545, Département d'Athérosclerose, Institut Pasteur de Lille, 1 rue du Professeur Calmette, 59019 Lille cédex, France
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Langenfeld MR, Forst T, Hohberg C, Kann P, Lübben G, Konrad T, Füllert SD, Sachara C, Pfützner A. Pioglitazone Decreases Carotid Intima-Media Thickness Independently of Glycemic Control in Patients With Type 2 Diabetes Mellitus. Circulation 2005; 111:2525-31. [PMID: 15883215 DOI: 10.1161/01.cir.0000165072.01672.21] [Citation(s) in RCA: 222] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Background—
Patients with type 2 diabetes mellitus are at high risk of cardiovascular disease. Carotid intima-media thickness (IMT) is a strong predictor of myocardial infarction and stroke.
Methods and Results—
We compared the effects of pioglitazone-based therapy (45 mg/d) and glimepiride-based treatment (2.7±1.6 mg/d) for 12 and 24 weeks on metabolic control (HbA
1c
), insulin resistance (homeostasis model assessment), and carotid IMT (B-mode ultrasonography) in a randomized controlled study in 173 orally treated patients with type 2 diabetes (66 women, 107 men; mean±SD age, 62.6±7.9 years; body mass index, 31.8±4.6 kg/m
2
; HbA
1c
, 7.5±0.9%). Treatment was generally well tolerated in both groups. Despite similar improvements in metabolic control (HbA
1c
) after 24 weeks (−0.8±0.9% [pioglitazone] versus −0.6±0.8% [glimepiride];
P
=NS), carotid IMT was reduced only in the pioglitazone group after 12 weeks (−0.033±0.052 versus −0.002±0.047 mm [glimepiride];
P
<0.01 between groups) and 24 weeks (−0.054±0.059 versus −0.011±0.058 mm [glimepiride];
P
<0.005 between groups). Insulin resistance was also improved only in the pioglitazone group (homeostasis model assessment, −2.2±3.4 versus −0.3±3.3;
P
<0.0001 between groups). Reduction of IMT correlated with improvement in insulin resistance (
r
=0.29,
P
<0.0005) and was independent of improvement in glycemic control (
r
=0.03,
P
=0.68).
Conclusions—
We found a substantial regression of carotid IMT, independent of improved glycemic control, after 12 and 24 weeks of pioglitazone treatment. This finding may have important prognostic implications for patients with type 2 diabetes mellitus.
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Affiliation(s)
- M R Langenfeld
- Institute of Clinical Research and Development GmbH, Mainz, Germany
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45
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Berkenstam A, Färnegårdh M, Gustafsson JA. Convergence of lipid homeostasis through liver X and thyroid hormone receptors. Mech Ageing Dev 2004; 125:707-17. [PMID: 15541766 DOI: 10.1016/j.mad.2004.05.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Members of the nuclear receptor gene family act as biological rheostats to maintain metabolic homeostasis in response to endocrine and nutritional changes. The liver X (LXR) and thyroid hormone (TR) receptors have been shown to regulate overlapping but distinct metabolic pathways important for overall lipid homeostasis. Dyslipidemia is one out of four key determinants for cardiovascular risk and both LXRs and TRs may provide attractive targets for intervention of cardiovascular disease. In this review we will compare the two receptor systems to highlight similarities and differences in structure and function with implications for development of novel treatments for dyslipidemia and atherosclerosis.
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46
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Henke BR. Peroxisome Proliferator-Activated Receptor α/γ Dual Agonists for the Treatment of Type 2 Diabetes. J Med Chem 2004; 47:4118-27. [PMID: 15293980 DOI: 10.1021/jm030631e] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Brad R Henke
- Metabolic and Viral Diseases Drug Discovery Research, Five Moore Drive, GlaxoSmithKline, Research Triangle Park, North Carolina 27709, USA.
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47
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Naka Y, Bucciarelli LG, Wendt T, Lee LK, Rong LL, Ramasamy R, Yan SF, Schmidt AM. RAGE axis: Animal models and novel insights into the vascular complications of diabetes. Arterioscler Thromb Vasc Biol 2004; 24:1342-9. [PMID: 15155381 DOI: 10.1161/01.atv.0000133191.71196.90] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Receptor for AGE (RAGE) is a multi-ligand member of the immunoglobulin superfamily of cell surface molecules. Engagement of RAGE by its signal transduction ligands evokes inflammatory cell infiltration and activation in the vessel wall. In diabetes, when fueled by oxidant stress, hyperglycemia, and superimposed stresses such as hyperlipidemia or acute balloon/endothelial denuding arterial injury, the ligand-RAGE axis amplifies vascular stress and accelerates atherosclerosis and neointimal expansion. In this brief synopsis, we review the use of rodent models to test these concepts. Taken together, our findings support the premise that RAGE is an amplification step in vascular inflammation and acceleration of atherosclerosis. Future studies must rigorously test the potential impact of RAGE blockade in human subjects; such trials are on the horizon.
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MESH Headings
- Animals
- Apolipoproteins E/deficiency
- Apolipoproteins E/genetics
- Arteriosclerosis/metabolism
- Arteriosclerosis/pathology
- Cell Adhesion Molecules/biosynthesis
- Coronary Restenosis/etiology
- Coronary Restenosis/metabolism
- Coronary Restenosis/pathology
- Cytokines/biosynthesis
- Diabetes Mellitus, Experimental/complications
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetic Angiopathies/metabolism
- Diabetic Angiopathies/pathology
- Disease Progression
- Drug Evaluation, Preclinical
- Glycation End Products, Advanced/metabolism
- Hyperlipidemias/blood
- Hyperlipidemias/complications
- Hyperlipidemias/genetics
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Models, Animal
- Oxidative Stress
- Rats
- Rats, Zucker
- Receptor for Advanced Glycation End Products
- Receptors, Immunologic/antagonists & inhibitors
- Receptors, Immunologic/deficiency
- Receptors, Immunologic/genetics
- Receptors, Immunologic/physiology
- Receptors, Immunologic/therapeutic use
- Signal Transduction
- Solubility
- Vasculitis/metabolism
- Vasculitis/pathology
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Affiliation(s)
- Yoshifumi Naka
- Department of Surgery, College of Physicians & Surgeons, Columbia University, New York, NY 10032, USA
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48
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Meir KS, Leitersdorf E. Atherosclerosis in the apolipoprotein-E-deficient mouse: a decade of progress. Arterioscler Thromb Vasc Biol 2004; 24:1006-14. [PMID: 15087308 DOI: 10.1161/01.atv.0000128849.12617.f4] [Citation(s) in RCA: 347] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Arguably the most critical advancement in the elucidation of factors affecting atherogenesis has been the development of mouse models of atherosclerosis. Among available models, the apolipoprotein E-deficient (apoE-/-) mouse is particularly popular because of its propensity to spontaneously develop atherosclerotic lesions on a standard chow diet. A Medline search reveals over 645 articles dedicated to studies using this reliable and convenient "super" animal model since its inception (Piedrahita JA et al, Proc Natl Acad Sci U S A 1992;89:4471-4475; Plump AS et al, Cell 1992;71:343-353) with a more or less steady increase from year to year. This review will examine our present understanding of the pathology and progression of plaques in this animal and highlight some of the nutritional, pharmacological, and genetic studies that have enhanced this understanding.
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Affiliation(s)
- Karen S Meir
- Department of Pathology, Hadassah University Hospital, Kiryat Hadassah, Jerusalem, Israel
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49
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Tailleux A, Torpier G, Mezdour H, Fruchart JC, Staels B, Fiévet C. Murine models to investigate pharmacological compounds acting as ligands of PPARs in dyslipidemia and atherosclerosis. Trends Pharmacol Sci 2004; 24:530-4. [PMID: 14559405 DOI: 10.1016/j.tips.2003.08.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Anne Tailleux
- Unité de Recherche INSERM 545, Département d'Athérosclérose, Institut Pasteur de Lille, France
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50
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Henke BR. 1. Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands and their therapeutic utility. PROGRESS IN MEDICINAL CHEMISTRY 2004; 42:1-53. [PMID: 15003718 DOI: 10.1016/s0079-6468(04)42001-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Brad R Henke
- Metabolic and Viral Diseases Drug Discovery Research, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, USA
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