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Candesartan protects against unilateral peripheral limb ischemia in type-2 diabetic rats: Possible contribution of PI3K-Akt-eNOS-VEGF angiogenic signaling pathway. Int Immunopharmacol 2023; 116:109817. [PMID: 36773570 DOI: 10.1016/j.intimp.2023.109817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/27/2023] [Accepted: 01/28/2023] [Indexed: 02/11/2023]
Abstract
Type-2 diabetes (T2DM) is known to be highly associated with increased risk for vascular complications including peripheral arterial diseases (PAD). Critical limb ischemia (CLI) is the most advanced stage of PAD. Current therapeutic options for diabetic patients experiencing vascular complications are limited to surgical revascularization with no effective pharmacotherapy available for clinical settings. This study is dedicated to evaluate the angiogenic potential of candesartan an angiotensin-II receptor blocker in an experimental model of vascular complications associating T2DM. T2DM was induced in rats through feeding with high fat diet for 6 weeks, followed by injection with streptozotocin (STZ, 30 mg/kg; i.p). After establishment of T2DM, unilateral CLI was induced through the ligation and excision of superficial femoral artery. Candesartan treatment (10 or 30 mg/kg; orally) was initiated one day post CLI and thereafter once daily for up to 14 days. T2DM rats that underwent CLI demonstrated impaired angiogenic signaling, increased inflammation and apoptosis in gastrocnemius muscle (GC). Candesartan reversed ischemic insult in T2DM rats subjected to unilateral CLI and induced reparative angiogenesis that was evident by increase in p-PI3K/PI3K, p-Akt/Akt, p-eNOS/eNOS, p-VEGFR2/VEGFR2 ratios, and VEGF levels. Candesartan treatment also increased levels of HO-1; while decreased caspase-3 apoptotic marker and levels of inflammatory markers; NF-κB and TNF-α, all of which were accompanied by preserved histological manifestations of GC muscles. Candesartan was able to combat limb ischemia under diabetic conditions which could pave the way for its therapeutic utility for diabetic patients experiencing vascular complications in clinical setting.
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Akhigbe R, Ajayi A. The impact of reactive oxygen species in the development of cardiometabolic disorders: a review. Lipids Health Dis 2021; 20:23. [PMID: 33639960 PMCID: PMC7916299 DOI: 10.1186/s12944-021-01435-7] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/26/2021] [Indexed: 02/07/2023] Open
Abstract
Oxidative stress, an alteration in the balance between reactive oxygen species (ROS) generation and antioxidant buffering capacity, has been implicated in the pathogenesis of cardiometabolic disorders (CMD). At physiological levels, ROS functions as signalling mediators, regulates various physiological functions such as the growth, proliferation, and migration endothelial cells (EC) and smooth muscle cells (SMC); formation and development of new blood vessels; EC and SMC regulated death; vascular tone; host defence; and genomic stability. However, at excessive levels, it causes a deviation in the redox state, mediates the development of CMD. Multiple mechanisms account for the rise in the production of free radicals in the heart. These include mitochondrial dysfunction and uncoupling, increased fatty acid oxidation, exaggerated activity of nicotinamide adenine dinucleotide phosphate oxidase (NOX), reduced antioxidant capacity, and cardiac metabolic memory. The purpose of this study is to discuss the link between oxidative stress and the aetiopathogenesis of CMD and highlight associated mechanisms. Oxidative stress plays a vital role in the development of obesity and dyslipidaemia, insulin resistance and diabetes, hypertension via various mechanisms associated with ROS-led inflammatory response and endothelial dysfunction.
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Affiliation(s)
- Roland Akhigbe
- Department of Physiology, College of Medicine, Ladoke Akintola University of Technology, Ogbomoso, Oyo State Nigeria
- Reproductive Biology and Toxicology Research Laboratories, Oasis of Grace Hospital, Osogbo, Osun State Nigeria
- Department of Chemical Sciences, Kings University, Odeomu, Osun Nigeria
| | - Ayodeji Ajayi
- Department of Physiology, College of Medicine, Ladoke Akintola University of Technology, Ogbomoso, Oyo State Nigeria
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Gao M, Du Y, Xie JW, Xue J, Wang YT, Qin L, Ma MM, Tang YB, Li XY. Redox signal-mediated TRPM2 promotes Ang II-induced adipocyte insulin resistance via Ca 2+-dependent CaMKII/JNK cascade. Metabolism 2018; 85:313-324. [PMID: 29775644 DOI: 10.1016/j.metabol.2018.05.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/21/2018] [Accepted: 05/11/2018] [Indexed: 10/16/2022]
Abstract
BACKGROUND AND OBJECTIVE Redox-sensitive transient receptor potential melastatin 2 (TRPM2) is a Ca2+-permeable, nonselective cation channel which plays a crucial role in various physiological processes. However, little is known whether TRPM2 is involved in adipocyte dysfunction during hypertension. In the present study, we determined the role of TRPM2 in angiotensin II (Ang II)-induced insulin resistance in adipocytes and the underlying mechanisms. METHODS Ang II-induced adipocyte insulin resistant model was conducted. Data from Ang II-induced hypertensive mice were used to measure the effects of TRPM2 inhibitor on insulin resistance in vivo. Whole-cell patch clamp technique, intracellular Ca2+ concentration measurement, glucose uptake assay, western blot, cDNA and siRNA transfection were employed to investigate the TRPM2/Ca2+/CaMKII/JNK signaling. RESULTS Ang II rose a cation current similar to that activated by hydrogen peroxide (H2O2) or ADP-ribose (ADPR), which was blocked by TRPM2 inhibitor or TRPM2 siRNA in adipocytes. Knockdown of TRPM2 significantly improved the lowered insulin sensitivity induced by Ang II, including insulin stimulated glucose uptake, phosphorylation of IRS1 and Akt, interaction between IR and IRS1 and the membrane translocation of GLUT4, whereas overexpression of TRPM2 resulted in the opposite effects. These results were related to the potentiated effects of TRPM2 on Ca2+ influx and CaMKII/JNK cascade activation upon Ang II-induced challenge. Notably, the pharmacological TRPM2 inhibitor, N-(p-amylcinnamoyl)anthranilic acid (ACA), was proved to improve insulin sensitivity in adipose tissue during Ang II-induced hypertension progress. CONCLUSIONS These data suggested that TRPM2 is a positive regulator of Ang II-induced adipocyte insulin resistance via Ca2+/CaMKII/JNK-dependent signaling pathway. Targeting TRPM2 may be a novel therapeutic strategy to treat hypertension-associated insulin resistance.
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Affiliation(s)
- Min Gao
- Department of Pharmacy, the Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510655, China.
| | - Yu Du
- Guangdong Provincial Key Laboratory of Liver Disease Research, Cell-gene Therapy Translational Medicine Research Center, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou 510630, China
| | - Jing-Wen Xie
- Department of Pharmacy, the Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510655, China
| | - Jing Xue
- Department of Pharmacy, the Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510655, China
| | - Yi-Ting Wang
- Department of Pharmacy, the Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510655, China
| | - Li Qin
- Department of Pharmacy, the Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510655, China
| | - Ming-Ming Ma
- Department of Pharmacology, Cardiac and Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China
| | - Yong-Bo Tang
- Department of Pharmacology, Cardiac and Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China
| | - Xiao-Yan Li
- Department of Pharmacy, the Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510655, China.
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The combination of valsartan and ramipril protects against blood vessel injury and lowers blood pressure. JOURNAL OF PHARMACEUTICAL INVESTIGATION 2016. [DOI: 10.1007/s40005-016-0241-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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5
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Karnik SS, Unal H, Kemp JR, Tirupula KC, Eguchi S, Vanderheyden PML, Thomas WG. International Union of Basic and Clinical Pharmacology. XCIX. Angiotensin Receptors: Interpreters of Pathophysiological Angiotensinergic Stimuli [corrected]. Pharmacol Rev 2015; 67:754-819. [PMID: 26315714 PMCID: PMC4630565 DOI: 10.1124/pr.114.010454] [Citation(s) in RCA: 215] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The renin angiotensin system (RAS) produced hormone peptides regulate many vital body functions. Dysfunctional signaling by receptors for RAS peptides leads to pathologic states. Nearly half of humanity today would likely benefit from modern drugs targeting these receptors. The receptors for RAS peptides consist of three G-protein-coupled receptors—the angiotensin II type 1 receptor (AT1 receptor), the angiotensin II type 2 receptor (AT2 receptor), the MAS receptor—and a type II trans-membrane zinc protein—the candidate angiotensin IV receptor (AngIV binding site). The prorenin receptor is a relatively new contender for consideration, but is not included here because the role of prorenin receptor as an independent endocrine mediator is presently unclear. The full spectrum of biologic characteristics of these receptors is still evolving, but there is evidence establishing unique roles of each receptor in cardiovascular, hemodynamic, neurologic, renal, and endothelial functions, as well as in cell proliferation, survival, matrix-cell interaction, and inflammation. Therapeutic agents targeted to these receptors are either in active use in clinical intervention of major common diseases or under evaluation for repurposing in many other disorders. Broad-spectrum influence these receptors produce in complex pathophysiological context in our body highlights their role as precise interpreters of distinctive angiotensinergic peptide cues. This review article summarizes findings published in the last 15 years on the structure, pharmacology, signaling, physiology, and disease states related to angiotensin receptors. We also discuss the challenges the pharmacologist presently faces in formally accepting newer members as established angiotensin receptors and emphasize necessary future developments.
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Affiliation(s)
- Sadashiva S Karnik
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Hamiyet Unal
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Jacqueline R Kemp
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Kalyan C Tirupula
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Satoru Eguchi
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Patrick M L Vanderheyden
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Walter G Thomas
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
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MAS-mediated antioxidant effects restore the functionality of angiotensin converting enzyme 2-angiotensin-(1-7)-MAS axis in diabetic rat carotid. BIOMED RESEARCH INTERNATIONAL 2014; 2014:640329. [PMID: 24877125 PMCID: PMC4022170 DOI: 10.1155/2014/640329] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 03/06/2014] [Indexed: 12/29/2022]
Abstract
We hypothesized that endothelial AT1-activated NAD(P)H oxidase-driven generation of reactive oxygen species during type I-diabetes impairs carotid ACE2-angiotensin-(1–7)-Mas axis functionality, which accounts for the impaired carotid flow in diabetic rats. We also hypothesized that angiotensin-(1–7) chronic treatment of diabetic rats restores carotid ACE2-angiotensin-(1–7)-Mas axis functionality and carotid flow. Relaxant curves for angiotensin II or angiotensin-(1–7) were obtained in carotid from streptozotocin-induced diabetic rats. Superoxide or hydrogen peroxide levels were measured by flow cytometry in carotid endothelial cells. Carotid flow was also determined. We found that endothelial AT1-activated NAD(P)H oxidase-driven generation of superoxide and hydrogen peroxide in diabetic rat carotid impairs ACE2-angiotensin-(1–7)-Mas axis functionality, which reduces carotid flow. In this mechanism, hydrogen peroxide derived from superoxide dismutation inhibits ACE2 activity in generating angiotensin-(1–7) seemingly by activating ICl,SWELL, while superoxide inhibits the nitrergic Mas-mediated vasorelaxation evoked by angiotensin-(1–7). Angiotensin-(1–7) treatment of diabetic rats restored carotid ACE2-angiotensin-(1–7)-Mas axis functionality by triggering a positive feedback played by endothelial Mas receptors, that blunts endothelial AT1-activated NAD(P)H oxidase-driven generation of reactive oxygen species. Mas-mediated antioxidant effects also restored diabetic rat carotid flow, pointing to the contribution of ACE2-angiotensin-(1–7)-Mas axis in maintaining carotid flow.
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7
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Koga M, Engberding N, Dikalova AE, Chang KH, Seidel-Rogol B, Long JS, Lassègue B, Jo H, Griendling KK. The bone morphogenic protein inhibitor, noggin, reduces glycemia and vascular inflammation in db/db mice. Am J Physiol Heart Circ Physiol 2013; 305:H747-55. [PMID: 23812391 DOI: 10.1152/ajpheart.00825.2012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vascular diseases frequently accompany diabetes mellitus. Based on the current understanding of atherosclerosis as an inflammatory disorder of the vascular wall, it has been speculated that diabetes may accelerate atherosclerosis by inducing a proinflammatory milieu in the vasculature. ANG II and bone morphogenic proteins (BMPs) have been implicated in vascular inflammation. We evaluated the effect of angiotensin receptor blockade by valsartan and BMP inhibition by noggin on markers of vascular inflammation in a mouse model of diabetes. Noggin had no effect on blood pressure but decreased serum glucose levels, whereas valsartan significantly decreased blood pressure, but not serum glucose. Both inhibitors reduced reactive oxygen species production in the aorta. Additionally, noggin and valsartan diminish gene transcription and protein expression of various inflammatory molecules in the vascular wall. These observations indicate that although both inhibitors block superoxide production and have similar effects on inflammatory gene expression, glycemia and blood pressure may represent a secondary target differentially affected by noggin and valsartan. Our data clearly identify the BMP pathway as a potentially potent therapeutic target in diabetic inflammatory vascular disease.
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Affiliation(s)
- Mitsuhisa Koga
- Division of Cardiology, Department of Medicine, Emory University, Atlanta, Georgia; and
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8
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Juni RP, Duckers HJ, Vanhoutte PM, Virmani R, Moens AL. Oxidative stress and pathological changes after coronary artery interventions. J Am Coll Cardiol 2013; 61:1471-81. [PMID: 23500310 DOI: 10.1016/j.jacc.2012.11.068] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 10/02/2012] [Accepted: 11/07/2012] [Indexed: 11/28/2022]
Abstract
Oxidative stress greatly influences the pathogenesis of various cardiovascular disorders. Coronary interventions, including balloon angioplasty and coronary stent implantation, are associated with increased vascular levels of reactive oxygen species in conjunction with altered endothelial cell and smooth muscle cell function. These alterations potentially lead to restenosis, thrombosis, or endothelial dysfunction in the treated artery. Therefore, the understanding of the pathophysiological role of reactive oxygen species (ROS) generated during or after coronary interventions, or both, is essential to improve the success rate of these procedures. Superoxide O2(·-) anions, whether derived from uncoupled endothelial nitric oxide synthase, nicotinamide adenine dinucleotide phosphate oxidase, xanthine oxidase, or mitochondria, are among the most harmful ROS. O2(·-) can scavenge nitric oxide, modify proteins and nucleotides, and induce proinflammatory signaling, which may lead to greater ROS production. Current innovations in stent technologies, including biodegradable stents, nitric oxide donor-coated stents, and a new generation of drug-eluting stents, therefore address persistent oxidative stress and reduced nitric oxide bioavailability after percutaneous coronary interventions. This review discusses the molecular mechanisms of ROS generation after coronary interventions, the related pathological events-including restenosis, endothelial dysfunction, and stent thrombosis-and possible therapeutic ways forward.
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Affiliation(s)
- Rio P Juni
- Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, the Netherlands
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Woods TC. Dysregulation of the Mammalian Target of Rapamycin and p27Kip1 Promotes Intimal Hyperplasia in Diabetes Mellitus. Pharmaceuticals (Basel) 2013; 6:716-27. [PMID: 24276258 PMCID: PMC3816729 DOI: 10.3390/ph6060716] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 05/01/2013] [Accepted: 05/08/2013] [Indexed: 01/19/2023] Open
Abstract
The proliferation and migration of vascular smooth muscle cells (VSMCs) in the intima of an artery, known as intimal hyperplasia, is an important component of cardiovascular diseases. This is seen most clearly in the case of in-stent restenosis, where drug eluting stents are used to deliver agents that prevent VSMC proliferation and migration. One class of agents that are highly effective in the prevention of in-stent restenosis is the mammalian Target of Rapamycin (mTOR) inhibitors. Inhibition of mTOR blocks protein synthesis, cell cycle progression, and cell migration. Key to the effects on cell cycle progression and cell migration is the inhibition of mTOR-mediated degradation of p27Kip1 protein. p27Kip1 is a cyclin dependent kinase inhibitor that is elevated in quiescent VSMCs and inhibits the G1 to S phase transition and cell migration. Under normal conditions, vascular injury promotes degradation of p27Kip1 protein in an mTOR dependent manner. Recent reports from our lab suggest that in the presence of diabetes mellitus, elevation of extracellular signal response kinase activity may promote decreased p27Kip1 mRNA and produce a relative resistance to mTOR inhibition. Here we review these findings and their relevance to designing treatments for cardiovascular disease in the presence of diabetes mellitus.
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Affiliation(s)
- Thomas Cooper Woods
- Tulane Heart and Vascular Institute and the Department of Physiology, School of Medicine, Tulane University, 1430 Tulane Avenue, SL-48, New Orleans, LA 70112, USA.
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10
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Abstract
Diabetes is a mutifactorial metabolic disorder that leads to a number of complications. Diabetes is estimated to affect 36 million people in the U.S.A., and the prevalence of diagnosed and undiagnosed diabetes is at 9.3% and continues to rise. Evidence from experimental animal models as well as humans has indicated that systemic inflammation plays a role in the pathophysiological processes of diabetes and is facilitated by innate immune responses. TLRs (Toll-like receptors) are key innate immune receptors that recognize conserved PAMPs (pathogen-associated molecular patterns), induce inflammatory responses essential for host defences and initiate an adaptive immune response. Although TLR expression is increased in a plethora of inflammatory disorders, the effects of metabolic aberrations on TLRs and their role in diabetes and its complications is still emerging. In the present paper, we provide a systematic review on how TLRs play a detrimental role in the pathogenic processes [increased blood sugar, NEFAs (non-esterified 'free' fatty acids), cytokines and ROS (reactive oxygen species)] that manifest diabetes. Furthermore, we will highlight some of the therapeutic strategies targeted at decreasing TLRs to abrogate inflammation in diabetes that may eventually result in decreased complications.
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11
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Otani H. Oxidative stress as pathogenesis of cardiovascular risk associated with metabolic syndrome. Antioxid Redox Signal 2011; 15:1911-26. [PMID: 21126197 DOI: 10.1089/ars.2010.3739] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Metabolic syndrome (MetS) is characterized by accumulation of visceral fat associated with the clustering of metabolic and pathophysiological cardiovascular risk factors: impaired glucose tolerance, dyslipidemia, and hypertension. Although the definition of MetS is different among countries, visceral obesity is an indispensable component of MetS. A growing body of evidence suggests that increased oxidative stress to adipocytes is central to the pathogenesis of cardiovascular disease in MetS. Increased oxidative stress to adipocytes causes dysregulated expression of inflammation-related adipocytokines in MetS, which contributes to obesity-associated vasculopathy and cardiovascular risk primarily through endothelial dysfunction. The purpose of present review is to unravel the mechanistic link between oxidative stress and cardiovascular risk in MetS, focusing on insulin resistance, hypertension, and atherosclerosis. Then, therapeutic opportunities translated from the bench to bedside will be provided to develop novel strategies to cardiovascular risk factors in MetS.
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Affiliation(s)
- Hajime Otani
- Second Department of Internal Medicine, Kansai Medical University, 10-15-Fumizono-cho, Moriguchi City, Japan.
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Guan W, Somanath PR, Kozak A, Goc A, El-Remessy AB, Ergul A, Johnson MH, Alhusban A, Soliman S, Fagan SC. Vascular protection by angiotensin receptor antagonism involves differential VEGF expression in both hemispheres after experimental stroke. PLoS One 2011; 6:e24551. [PMID: 21912702 PMCID: PMC3164729 DOI: 10.1371/journal.pone.0024551] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 08/12/2011] [Indexed: 11/18/2022] Open
Abstract
We identified that the angiotensin receptor antagonist, candesartan, has profound neurovascular protective properties when administered after ischemic stroke and was associated with a proangiogenic state at least partly explained by vascular endothelial growth factor A (VEGFA). However, the spatial distribution of vascular endothelial growth factor (VEGF) isoforms and their receptors remained unknown. Protein analysis identified a significant increase in vascular endothelial grow factor B (VEGFB) in the cerebrospinal fluid (CSF) and the ischemic hemispheres (with increased VEGF receptor 1 activation) of treated animals (p<0.05) which was co-occurring with an increase in protein kinase B (Akt) phosphorylation (p<0.05). An increase in VEGFA protein in the contralesional hemisphere corresponded to a significant increase in vascular density at seven days (p<0.01) after stroke onset. Vascular restoration by candesartan after stroke maybe related to differential regional upregulation of VEGFB and VEGFA, promoting a “prosurvival state” in the ischemic hemisphere and angiogenesis in the contralesional side, respectively. These vascular changes in both hemispheres after effective treatment are likely to contribute to enhanced recovery after stroke.
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Affiliation(s)
- Weihua Guan
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
| | - Payaningal R. Somanath
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
| | - Anna Kozak
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
| | - Anna Goc
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
| | - Azza B. El-Remessy
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
| | - Adviye Ergul
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
- Departments of Physiology, Georgia Health Sciences University, Augusta, Georgia, United States of America
| | - Maribeth H. Johnson
- Department of Biostatistics, Georgia Health Sciences University, Augusta, Georgia, United States of America
| | - Ahmed Alhusban
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
| | - Sahar Soliman
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
| | - Susan C. Fagan
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia, United States of America
- Charlie Norwood VA Medical Center, Augusta, Georgia, United States of America
- Department of Neurology, Georgia Health Sciences University, Augusta, Georgia, United States of America
- * E-mail:
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Weight loss and hypophagia after high-dose AT1-blockade is only observed after high dosing and depends on regular leptin signalling but not blood pressure. Naunyn Schmiedebergs Arch Pharmacol 2011; 383:373-84. [PMID: 21287150 DOI: 10.1007/s00210-011-0602-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 01/12/2011] [Indexed: 01/11/2023]
Abstract
AT(1)-blockade has been shown to induce weight loss in animals or patients. The aim of this study was to investigate whether weight reduction after AT(1)-blockade is dependent on dose, blood pressure reduction and leptin signalling. Spontaneously hypertensive rats (SHR) and lean and obese Zucker rats were treated for 4 weeks with candesartan (0, 2, 6 or 16 mg/kg/day). Body weight, food intake and hypothalamic mRNA levels of (an)orexigenic peptides were determined. Obese Zucker rats served as a model of primary leptin resistance. In SHR, body mass index and food intake were decreased selectively by 16 mg/kg/day candesartan but not after using normal (2 mg/kg/day) or supranormal (6 mg/kg/day) doses. Correlation analysis between blood pressure and body weight indicated no relationship of hypotensive potency on weight loss. The hypothalamic mRNA levels of the orexigenic peptide MCH (melanin-concentrating hormone) were diminished in parallel. Consistent to the results in SHRs, 16 mg/kg/day candesartan revealed a decrease of body weight, food intake and hypothalamic MCH mRNA levels in lean Zucker rats. In obese Zucker rats, none of these parameters were reduced by candesartan. Loss of body weight and hypophagia are not general features of AT(1)-blockers, since neither was seen after normal or moderately supranormal doses, but they were, after the highest doses. These actions of AT(1)-blockers occur independently of their ability to lower blood pressure. They do depend on an intact leptin signalling, since they were absent in obese Zucker rats that feature a genetic mutation of the leptin receptor.
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Armstrong ZB, Boughner DR, Drangova M, Rogers KA. Angiotensin II type 1 receptor blocker inhibits arterial calcification in a pre-clinical model. Cardiovasc Res 2010; 90:165-70. [DOI: 10.1093/cvr/cvq391] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Yi I, Lee JJ, Park JS, Zhang WY, Kim IS, Kim Y, Shin CY, Kim HS, Myung CS. Enhanced effect of losartan and rosuvastatin on neointima hyperplasia. Arch Pharm Res 2010; 33:593-600. [PMID: 20422369 DOI: 10.1007/s12272-010-0414-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 01/11/2010] [Accepted: 01/24/2010] [Indexed: 10/19/2022]
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16
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Groenewegen HC, van der Harst P, Roks AJM, Buikema H, Zijlstra F, van Gilst WH, de Smet BJGL. Effects of angiotensin II and angiotensin II type 1 receptor blockade on neointimal formation after stent implantation. Int J Cardiol 2008; 126:209-15. [PMID: 17482691 DOI: 10.1016/j.ijcard.2007.03.127] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Revised: 01/28/2007] [Accepted: 03/30/2007] [Indexed: 11/23/2022]
Abstract
BACKGROUND To evaluate the effect of supraphysiological levels of angiotensin II and selective angiotensin II type 1 receptor (AT1-receptor) blockade on neointimal formation and systemic endothelial function after stent implantation in the rat abdominal aorta. METHODS Male Wistar rats were randomized to one of three groups; control (n=8), angiotensin II infusion (n=9, 200 ng/kg/min), or candesartan cilexetil (n=8,AT1-receptor blocker; rats received 14.4 mg kg(-1) day(-1)). Stents were implanted in the abdominal aorta. Histological analyses were performed at 4 weeks. Endothelial function was determined in isolated thoracic aortic rings. RESULTS Neointimal area was increased in the angiotensin II treated group versus the control group, 0.88 mm(2)+/-0.21 versus 0.66 mm(2)+/-0.16 (P<0.05). Neointimal thickness was 171 microm+/-44 in angiotensin II treated animals and 120 microm+/-25 in the control group (P<0.05). In addition, endothelial function was attenuated in angiotensin II treated animals (P=0.01). Candesartan cilexetil treatment did not result in reduction of neointimal area and did not reduce neointimal thickness compared to the control group. Candesartan had no effect on endothelial function. CONCLUSIONS Supraphysiological levels of angiotensin II aggravates neointimal formation in the stented rat abdominal aorta, and in parallel decreases endothelial function. AT1-receptor blockade does not reduce neointimal formation in rats without supraphysiological angiotensin II levels.
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Affiliation(s)
- Hendrik C Groenewegen
- Department of Clinical Pharmacology, University Medical Center Groningen, University of Groningen, The Netherlands.
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17
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Dasu MR, Riosvelasco AC, Jialal I. Candesartan inhibits Toll-like receptor expression and activity both in vitro and in vivo. Atherosclerosis 2008; 202:76-83. [PMID: 18495130 DOI: 10.1016/j.atherosclerosis.2008.04.010] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2007] [Revised: 03/25/2008] [Accepted: 04/09/2008] [Indexed: 10/22/2022]
Abstract
INTRODUCTION Toll-like receptors play an important role in the innate immune system and are found to be crucial in severe diseases like sepsis, atherosclerosis, and arthritis. TLR2 and TLR4 expression is upregulated in the inflammatory diseases. Angiotensin II in addition to stimulating vasoconstriction also induces an increase in ROS and a proinflammatory phenotype via AT(1)R. Angiotensin II type-1 receptor blocker (ARB), widely used as an antihypertensive drug, has been reported to also have anti-inflammatory effects. Thus, we investigated whether an ARB exerts anti-inflammatory effects via inhibiting TLR2 and TLR4 expression. METHODS AND RESULTS Monocytes were isolated from healthy human volunteers and treated with the synthetic lipoprotein Pam3CSK4 or LPS in the absence or presence of candesartan. Pretreatment of human monocytes with candesartan significantly decreased Pam3CSK4 or LPS induced TLR2 and TLR4 expression of both mRNA and protein levels (P<0.05 vs. control) along with decrease in the activity of NF-kappaB and the expression of IL-1beta, IL-6, TNF-alpha, and MCP-1. Furthermore, candesartan treated mice show decreased TLR2 and TLR4 expression compared to vehicle control mice. CONCLUSION Pam3CSK4 and LPS induced TLR2 and TLR4 expression at mRNA and protein levels are inhibited by candesartan both in vitro and in vivo. Thus, we define a novel pathway by which candesartan could induce anti-inflammatory effects.
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Affiliation(s)
- Mohan R Dasu
- Laboratory for Atherosclerosis and Metabolic Research, University of California Davis Medical Center, Sacramento, CA 95817, United States
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18
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Krämer S, Kron S, Wang-Rosenke Y, Loof T, Khadzhynov D, Morgera S, Kawachi H, Shimizu F, Martini S, Neumayer HH, Peters H. Rosuvastatin is additive to high-dose candesartan in slowing progression of experimental mesangioproliferative glomerulosclerosis. Am J Physiol Renal Physiol 2008; 294:F801-11. [DOI: 10.1152/ajprenal.00148.2007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Rosuvastatin is additive to high-dose candesartan in slowing progression of experimental mesangioproliferative glomerulosclerosis (GS). Progressive mesangioproliferative glomerulonephritis, mostly IgA nephropathy, is a major cause of end-stage kidney disease worldwide. In a chronic-progressive model of mesangioproliferative GS, we tested the renoprotective efficacy of rosuvastatin alone and in combination with a high-dose of the AT1blocker candesartan. Treatment was started 1 wk after disease induction (anti-thy1 antibody injection into uninephrectomized rats) and continued until week 20. Tubulointerstitial expression of the key fibrosis mediator transforming growth factor (TGF)-β served as the main marker of disease progression. Compared with the untreated GS rats (475 ± 52 pg/ml), tubulointerstitial TGF-β1protein expression was significantly reduced by both single therapies (rosuvastatin −47%, candesartan −51%, P < 0.01). Tubulointerstitial matrix accumulation (matrix score in GS: 64 ± 7%) was relatively reduced by −45 and −52%, respectively ( P < 0.01). The combination of rosuvastatin and candesartan had significantly greater effects on tubulointerstitial TGF-β1expression (−82% vs. GS) and matrix accumulation (−83% vs. GS) ( P < 0.001 vs. GS, P < 0.05 vs. single therapy) than either drug alone. Similar additive beneficial effects were observed for renal fibronectin and tissue inhibitor of metalloproteinase-1 expression, cell proliferation, macrophage infiltration, proteinuria, and kidney function. In conclusion, rosuvastatin limits the progressive course of anti-thy1-induced GS toward chronic tubulointerstitial fibrosis and renal insufficiency to a degree comparable to the one achieved by a high dose of the AT1antagonist candesartan. Combined treatment yields significantly greater actions on renal TGF-β overexpression and matrix accumulation, cell proliferation, and macrophage infiltration. The results suggest that rosuvastatin and an AT1blocker independently interfere with separate key pathways involved in the progression of chronic mesangioproliferative GS.
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19
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Igarashi M, Hirata A, Nozaki H, Kadomoto-Antsuki Y, Tominaga M. Role of angiotensin II type-1 and type-2 receptors on vascular smooth muscle cell growth and glucose metabolism in diabetic rats. Diabetes Res Clin Pract 2007; 75:267-77. [PMID: 16934905 DOI: 10.1016/j.diabres.2006.06.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2006] [Revised: 06/07/2006] [Accepted: 06/26/2006] [Indexed: 12/31/2022]
Abstract
This study investigates the mechanisms whereby angiotensin II (Ang II) signaling contributes to cell growth and glucose metabolism in cultured vascular smooth muscle cells (VSMCs) from male Wistar fatty rats (WF) and their littermates (Wistar lean rats, WL). The levels of the medial outgrowth rate of VSMCs and Ang II type-1 receptors (AT1R) in aortae from WF were more enhanced than those in aortae from WL, but the level of Ang II type-2 receptors (AT2R) was not different. A mixture of insulin and Ang II additively increased the values of [(3)H]-thymidine incorporation in WF and WL, which was inhibited by olmesartan, an AT1 receptor blockade (ARB), but not by PD123,319, an AT2 receptor blockade. Similarly, insulin and Ang II phosphorylated extracellular-regulated protein kinase 1/2, retinoblastoma tumor suppressor protein, and cyclic AMP response element binding protein, and these levels were higher in WF than in WL. In contrast, the phosphorylation was suppressed by olmesartan but not PD123,319. Insulin-stimulated Akt phosphorylation and 2-deoxy-d-glucose uptake in WF were significantly reduced by Ang II, and the reduction was ameliorated by olmesartan but not PD123,319. Differently from the result of Akt, the phosphorylation of the insulin-stimulated insulin receptor beta-subunit was not affected by Ang II, olmesartan, or PD123,319. However, the phosphorylation of insulin-stimulated insulin-related substrate (IRS)-1 was suppressed by Ang II, and the suppression was ameliorated by olmesartan, but not PD123,319, in both WF and WL. In contrast, the phosphorylation of IRS-1 on Ser(307) was elevated by the Ang II, and the elevation was suppressed by olmesartan, but not by PD123,319, in both WF and WL. These findings demonstrated that Ang II signaling contributes to cell proliferation and inhibition of the insulin signaling pathways through AT1R, but not trough AT2R, in both non-diabetic and diabetic VSMCs.
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MESH Headings
- Angiotensin II Type 1 Receptor Blockers/pharmacology
- Angiotensin II Type 2 Receptor Blockers
- Animals
- Aorta/physiopathology
- Blood Glucose/metabolism
- Cells, Cultured
- DNA Replication
- Deoxyglucose/metabolism
- Diabetes Mellitus, Experimental/blood
- Diabetes Mellitus, Experimental/physiopathology
- Imidazoles/pharmacology
- Male
- Muscle, Smooth, Vascular/growth & development
- Muscle, Smooth, Vascular/physiopathology
- Nuclear Proteins/metabolism
- Obesity
- Rats
- Rats, Wistar
- Receptor, Angiotensin, Type 1/drug effects
- Receptor, Angiotensin, Type 1/physiology
- Receptor, Angiotensin, Type 2/drug effects
- Receptor, Angiotensin, Type 2/physiology
- Tetrazoles/pharmacology
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Affiliation(s)
- Masahiko Igarashi
- Department of Laboratory Medicine, Yamagata University School of Medicine, 2-2-2, Iida-nishi, Yamagata 990-9585, Japan.
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20
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Mehta PK, Griendling KK. Angiotensin II cell signaling: physiological and pathological effects in the cardiovascular system. Am J Physiol Cell Physiol 2006; 292:C82-97. [PMID: 16870827 DOI: 10.1152/ajpcell.00287.2006] [Citation(s) in RCA: 1410] [Impact Index Per Article: 78.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The renin-angiotensin system is a central component of the physiological and pathological responses of cardiovascular system. Its primary effector hormone, angiotensin II (ANG II), not only mediates immediate physiological effects of vasoconstriction and blood pressure regulation, but is also implicated in inflammation, endothelial dysfunction, atherosclerosis, hypertension, and congestive heart failure. The myriad effects of ANG II depend on time (acute vs. chronic) and on the cells/tissues upon which it acts. In addition to inducing G protein- and non-G protein-related signaling pathways, ANG II, via AT(1) receptors, carries out its functions via MAP kinases (ERK 1/2, JNK, p38MAPK), receptor tyrosine kinases [PDGF, EGFR, insulin receptor], and nonreceptor tyrosine kinases [Src, JAK/STAT, focal adhesion kinase (FAK)]. AT(1)R-mediated NAD(P)H oxidase activation leads to generation of reactive oxygen species, widely implicated in vascular inflammation and fibrosis. ANG II also promotes the association of scaffolding proteins, such as paxillin, talin, and p130Cas, leading to focal adhesion and extracellular matrix formation. These signaling cascades lead to contraction, smooth muscle cell growth, hypertrophy, and cell migration, events that contribute to normal vascular function, and to disease progression. This review focuses on the structure and function of AT(1) receptors and the major signaling mechanisms by which angiotensin influences cardiovascular physiology and pathology.
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Affiliation(s)
- Puja K Mehta
- Division of Cardiology, 319 WMB, Emory University, 1639 Pierce Drive, Atlanta, GA 30322, USA
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21
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Clark MG, Rattigan S, Barrett EJ. Nutritive blood flow as an essential element supporting muscle anabolism. Curr Opin Clin Nutr Metab Care 2006; 9:185-9. [PMID: 16607114 DOI: 10.1097/01.mco.0000222097.90890.c2] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PURPOSE OF REVIEW Much of the recent literature concerning hormonal effects on muscle assumes that full perfusion occurs at all times such that nutrient and hormone delivery is complete. New methods to measure the extent of nutritive blood flow in muscle show that this is not the case and that anabolic hormones such as insulin increase nutritive flow and that other agents that increase bulk flow have little effect. This review examines the latest developments concerning insulin action to increase nutritive perfusion of muscle and agents that interact with this effect and which could potentially modulate anabolism. RECENT FINDINGS We examine recent attempts to define the anatomical nature of non-nutritive flow route in muscle, the quick onset of insulin action to recruit nutritive blood flow at doses lower than that which activates glucose uptake and bulk blood flow, actions of the inflammatory cytokine tumour necrosis factor alpha TNFalpha to oppose physiologic insulin action, interfibrillar fat depots that grow on the non-nutritive vasculature of muscle and underpin a 'vascrine hypothesis', and drugs that reduce insulin resistance by ameliorating vascular dysfunction. SUMMARY Recognition that nutrient and hormone delivery to muscle is controlled by microvascular perfusion and not necessarily by bulk blood flow is the key issue.
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22
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Dendorfer A, Dominiak P, Schunkert H. ACE inhibitors and angiotensin II receptor antagonists. Handb Exp Pharmacol 2005:407-42. [PMID: 16596809 DOI: 10.1007/3-540-27661-0_15] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The biological actions of angiotensin II (ANG), the most prominent hormone of the renin-angiotensin-aldosterone system (RAAS), may promote the development of atherosclerosis in many ways. ANG aggravates hypertension, metabolic syndrome, and endothelial dysfunction, and thereby constitutes a major risk factor for cardiovascular disease. The formation of atherosclerotic lesions involves local uptake, synthesis and oxidation of lipids, inflammation, as well as cellular migration and proliferation--mechanisms that may all be enhanced by ANG via its AT1 receptor. ANG may also increase the risk of acute thrombosis by destabilizing atherosclerotic plaques and enhancing the activity of thrombocytes and coagulation. After myocardial infarction, ANG promotes myocardial remodeling and fibrosis, and its many pathological mechanisms deteriorate the prognosis of these high-risk patients in particular. Therapeutically, inhibitors of the angiotensin I-converting enzyme (ACEI) and AT1 receptor blockers (ARB) are available to suppress the generation and cellular signaling of ANG, respectively. Despite major differences in the efficacy of ANG suppression and the modulation of other hormones and receptors, both classes of drugs are generally effective in attenuating numerous pathomechanisms of ANG in vitro, and in diminishing the development of atherosclerotic lesions and restenosis after angioplasty in various animal models. In clinical therapy, ACEI and ACE are well-tolerated antihypertensive drugs that also improve the prognosis of heart failure patients. After myocardial infarction and in stable coronary heart disease, ACEI have been shown to reduce mortality in a manner independent of hemodynamic alterations. However, there is little evidence that inhibitors of the RAAS may be effective against arterial restenosis, and a possible benefit of these substances compared to other antihypertensive drugs in the primary prevention of coronary heart disease in hypertensive patients is still a matter of debate, possibly depending on the specific substance and condition being investigated. As such, the general clinical efficacy of ACEI and ARB may be due to a positive influence on hemodynamic load, vascular function, myocardial remodeling, and neuro-humoral regulation, rather than to a direct attenuation of the atherosclerotic process. Further therapeutic advances may be achieved by identifying optimum drugs, patient populations, and treatment protocols.
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Affiliation(s)
- A Dendorfer
- Medizinische Klinik II, Universitätsklinikum Schleswig-Hostein, Lübeck, Germany
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23
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Nishimatsu H, Suzuki E, Satonaka H, Takeda R, Omata M, Fujita T, Nagai R, Kitamura T, Hirata Y. Endothelial dysfunction and hypercontractility of vascular myocytes are ameliorated by fluvastatin in obese Zucker rats. Am J Physiol Heart Circ Physiol 2004; 288:H1770-6. [PMID: 15550522 DOI: 10.1152/ajpheart.00751.2004] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
To study the mechanisms of vascular dysfunction in diabetes mellitus, we examined the responses of the aorta to adrenomedullin (AM) and ANG II in obese Zucker (OZ), lean Zucker (LZ), and OZ rats administered fluvastatin (OZ + Flu). AM-induced endothelium-dependent vasorelaxation was impaired in OZ rats compared with LZ rats, and fluvastatin restored AM-induced, endothelium-dependent vasorelaxation (%Deltatension at 10(-7) mol/l AM; LZ, -85.1 +/- 3.1%; OZ, -50.7 +/- 2.5%; OZ + Flu, -75.6 +/- 2.7%). Expression of endothelial nitric oxide synthase (eNOS) and Akt phosphorylation in response to AM (10(-7) mol/l) were also diminished in OZ rats. Fluvastatin restored the eNOS expression and Akt phosphorylation [eNOS expression (relative intensity): LZ, 2.3 +/- 0.4; OZ, 1.0 +/- 0.2; OZ + Flu, 1.8 +/- 0.3; Akt phosphorylation (relative intensity): LZ, 2.3 +/- 0.2; OZ, 1.0 +/- 0.3; OZ + Flu, 1.9 +/- 0.2]. ANG II-induced vasoconstriction was enhanced in the aortic rings of OZ rats compared with LZ rats, and this enhanced vasoconstriction was partially normalized by fluvastatin and was abolished when the aorta of OZ rats was preincubated with the Rho kinase inhibitor Y-27632. GTPgammaS-induced contraction of permeabilized aortic smooth muscle cells, which is an indicator of the Rho-dependent Ca(2+) sensitization of contraction, was enhanced in OZ rats compared with LZ rats, and this enhanced contraction was suppressed in OZ + Flu rats. These results suggested that endothelium-dependent vasorelaxation was impaired, Ca(2+) sensitization of contraction was augmented in blood vessels of OZ rats and that fluvastatin restored vascular function by activating the Akt-dependent pathway and inhibiting the Rho-dependent pathway.
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MESH Headings
- Adrenomedullin
- Angiotensin II/pharmacology
- Animals
- Aorta/drug effects
- Aorta/physiology
- Calcium/metabolism
- Diabetic Angiopathies/drug therapy
- Diabetic Angiopathies/metabolism
- Diabetic Angiopathies/physiopathology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiopathology
- Fatty Acids, Monounsaturated/pharmacology
- Fluvastatin
- Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology
- Indoles/pharmacology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiopathology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/physiology
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type III
- Obesity/drug therapy
- Obesity/metabolism
- Obesity/physiopathology
- Peptides/pharmacology
- Phosphorylation/drug effects
- Protein Serine-Threonine Kinases/metabolism
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins c-akt
- Rats
- Rats, Zucker
- Vasoconstriction/drug effects
- Vasoconstriction/physiology
- Vasoconstrictor Agents/pharmacology
- Vasodilation/drug effects
- Vasodilation/physiology
- Vasodilator Agents/pharmacology
- rho GTP-Binding Proteins/metabolism
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Affiliation(s)
- Hiroaki Nishimatsu
- Department of Urology, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655 Japan
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Wakeyama T, Ogawa H, Iida H, Takaki A, Iwami T, Mochizuki M, Tanaka T. Effects of candesartan and probucol on restenosis after coronary stenting: results of insight of stent intimal hyperplasia inhibition by new angiotensin II receptor antagonist (ISHIN) trial. Circ J 2003; 67:519-24. [PMID: 12808270 DOI: 10.1253/circj.67.519] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The purpose of this study was to determine whether candesartan and its combination with probucol reduce restenosis after coronary stenting. A total of 132 patients who successfully underwent stenting were randomly assigned to a control group (n=45), a candesartan group (8 mg daily, n=43), or a candesartan plus probucol group (+ probucol 500 mg daily, n=44). No differences in late loss were observed between the control and candesartan groups. In the candesartan plus probucol group, late loss was significantly smaller than in the control and candesartan groups (p=0.003, 0.015). The restenosis rate was 27% in the control group, 26% in the candesartan group (p>0.99), and 11% in the candesartan plus probucol group (p=0.104 vs the control group and p=0.103 vs the candesartan group). Intravascular ultrasound revealed no differences in stent area among the 3 groups, and no differences in lumen area or in intimal hyperplasia area between the control and candesartan groups. However, the intimal hyperplasia area in the candesartan plus probucol group was significantly less than that in the control and candesartan groups (p<0.001, p<0.001). This study demonstrated that candesartan failed to inhibit the neointimal hyperplasia and although the combination treatment did reduce neointimal hyperplasia, it did not statistically reduce the restenosis rate.
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Kalantarinia K, Siragy HM. The choice of antihypertensive drugs in patients with diabetes: angiotensin II and beyond. Curr Diab Rep 2002; 2:423-30. [PMID: 12643168 DOI: 10.1007/s11892-002-0107-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Affecting over 16 million individuals, diabetes mellitus is among the leading causes of mortality in the United States. Hypertension is a common finding among diabetic patients and increases their morbidity and mortality. Control of blood pressure in this population has been shown to improve outcomes. Recent randomized trials have proven the benefit of lower blood pressure goals in the treatment of hypertensive patients as compared with nondiabetic patients. Randomized controlled trials have also demonstrated that the selection of the antihypertensive agent used to treat hypertension in diabetic patients is as important as the reduction of blood pressure levels to the recommended levels. In this article, we first focus on the importance of the renin angiotensin system in the development of diabetic complications, and then we review the results of the recent studies that have had a major impact on the treatment of hypertension in diabetes.
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Affiliation(s)
- Kambiz Kalantarinia
- Department of Medicine, Division of Endocrinology & Metabolism, Box 800746, University of Virginia Health System, Charlottesville, VA 22908-0746, USA
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