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Wu KLH, Wu CW, Chen LW, Chang HH, Cheng CL, Wu CY, Lee YC, Chen IC, Hung CY, Liu WC. Dysregulation of mitochondrial dynamics mediated aortic perivascular adipose tissue-associated vascular reactivity impairment under excessive fructose intake. Nutr Metab (Lond) 2024; 21:4. [PMID: 38167066 PMCID: PMC10763079 DOI: 10.1186/s12986-023-00776-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024] Open
Abstract
Excessive fructose intake presents the major risk factor for metabolic cardiovascular disease. Perivascular adipose tissue (PVAT) is a metabolic tissue and possesses a paracrine function in regulating aortic reactivity. However, whether and how PVAT alters vascular function under fructose overconsumption remains largely unknown. In this study, male Sprague-Dawley rats (8 weeks old) were fed a 60% high fructose diet (HFD) for 12 weeks. Fasting blood sugar, insulin, and triglycerides were significantly increased by HFD intake. Plasma adiponectin was significantly enhanced in the HFD group. The expression of uncoupling protein 1 (UCP1) and mitochondrial mass were reduced in the aortic PVAT of the HFD group. Concurrently, the expression of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) and mitochondrial transcription factor A (TFAM) were suppressed. Furthermore, decreased fusion proteins (OPA1, MFN1, and MFN2) were accompanied by increased fission proteins (FIS1 and phospho-DRP1). Notably, the upregulated α-smooth muscle actin (α-SMA) and osteocalcin in the PVAT were concurrent with the impaired reactivity of aortic contraction and relaxation. Coenzyme Q10 (Q, 10 mg/100 mL, 4 weeks) effectively reversed the aforementioned events induced by HFD. Together, these results suggested that the dysregulation of mitochondrial dynamics mediated HFD-triggered PVAT whitening to impair aortic reactivity. Fortunately, coenzyme Q10 treatment reversed HFD-induced PVAT whitening and aortic reactivity.
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Affiliation(s)
- Kay L H Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, ROC
- Department of Senior Citizen Services, National Tainan Institute of Nursing, Tainan, Taiwan, ROC
| | - Chih-Wei Wu
- Plastic Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, ROC
- Department of Counseling, National ChiaYi University, Chiayi, Taiwan, ROC
| | - Lee-Wei Chen
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, ROC
- Institute of Emergency and Critical Care Medicine, National Yang-Ming Chiao Tung University, Taipei, Taiwan, ROC
- Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung, Taiwan, ROC
| | - Hsiao-Huang Chang
- Department of Surgery, School of Medicine, Taipei Medical University, Taipei, Taiwan, ROC
- Division of Cardiovascular Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Ching-Li Cheng
- Department of Nursing, National Tainan Institute of Nursing, Tainan, Taiwan, ROC
| | - Cai-Yi Wu
- Plastic Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, ROC
| | - Yu-Chi Lee
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, ROC
| | - I-Chun Chen
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, ROC
| | - Chun-Ying Hung
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, ROC
| | - Wen-Chung Liu
- Plastic Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, ROC.
- Department of Surgery, School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung, Taiwan, ROC.
- School of Medicine, College of Medicine, National Sun Yat-Sen University, Kaohsiung, Taiwan, ROC.
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Bruder-Nascimento T, Faulkner JL, Haigh S, Kennard S, Antonova G, Patel VS, Fulton DJR, Chen W, Belin de Chantemèle EJ. Leptin Restores Endothelial Function via Endothelial PPARγ-Nox1-Mediated Mechanisms in a Mouse Model of Congenital Generalized Lipodystrophy. Hypertension 2019; 74:1399-1408. [PMID: 31656096 DOI: 10.1161/hypertensionaha.119.13398] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Leptin is the current treatment for metabolic disorders associated with acquired and congenital generalized lipodystrophy (CGL). Although excess leptin levels have been associated with vascular inflammation and cardiovascular disease in the context of obesity, the effects of chronic leptin treatment on vascular function remain unknown in CGL. Here, we hypothesized that leptin treatment will improve endothelial function via direct vascular mechanisms. We investigated the cardiovascular consequences of leptin deficiency and supplementation in male gBscl2-/- (Berardinelli-Seip 2 gene-deficient) mice-a mouse model of CGL. CGL mice exhibited reduced adipose mass and leptin levels, as well as impaired endothelium-dependent relaxation. Blood vessels from CGL mice had increased NADPH Oxidase 1 (Nox1) expression and reactive oxygen species production, and selective Nox1 inhibition restored endothelial function. Remarkably, chronic and acute leptin supplementation restored endothelial function via a PPARγ-dependent mechanism that decreased Nox1 expression and reactive oxygen species production. Selective ablation of leptin receptors in endothelial cells promoted endothelial dysfunction, which was restored by Nox1 inhibition. Lastly, we confirmed in aortic tissue from older patients undergoing cardiac bypass surgery that acute leptin can promote signaling in human blood vessels. In conclusion, in gBscl2-/- mice, leptin restores endothelial function via peroxisome proliferator activated receptor gamma-dependent decreases in Nox1. Furthermore, we provide the first evidence that vessels from aged patients remain leptin sensitive. These data reveal a new direct role of leptin receptors in the control of vascular homeostasis and present leptin as a potential therapy for the treatment of vascular disease associated with low leptin levels.
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Affiliation(s)
- Thiago Bruder-Nascimento
- From the Vascular Biology Center (T.B.-N., J.L.F., S.H., S.K., G.A., D.J.R.F., E.J.B.), Medical College of Georgia, Augusta University.,Department of Pediatrics, Division of Endocrinology, University of Pittsburgh, PA (T.B.-N.)
| | - Jessica L Faulkner
- From the Vascular Biology Center (T.B.-N., J.L.F., S.H., S.K., G.A., D.J.R.F., E.J.B.), Medical College of Georgia, Augusta University
| | - Stephen Haigh
- From the Vascular Biology Center (T.B.-N., J.L.F., S.H., S.K., G.A., D.J.R.F., E.J.B.), Medical College of Georgia, Augusta University
| | - Simone Kennard
- From the Vascular Biology Center (T.B.-N., J.L.F., S.H., S.K., G.A., D.J.R.F., E.J.B.), Medical College of Georgia, Augusta University
| | - Galina Antonova
- From the Vascular Biology Center (T.B.-N., J.L.F., S.H., S.K., G.A., D.J.R.F., E.J.B.), Medical College of Georgia, Augusta University
| | - Vijay S Patel
- Section of Cardiothoracic Surgery, Department of Surgery (V.S.P.), Medical College of Georgia, Augusta University
| | - David J R Fulton
- From the Vascular Biology Center (T.B.-N., J.L.F., S.H., S.K., G.A., D.J.R.F., E.J.B.), Medical College of Georgia, Augusta University
| | - Weiqin Chen
- Department of Physiology (W.C.), Medical College of Georgia, Augusta University
| | - Eric J Belin de Chantemèle
- From the Vascular Biology Center (T.B.-N., J.L.F., S.H., S.K., G.A., D.J.R.F., E.J.B.), Medical College of Georgia, Augusta University.,Department of Medicine, Division of Cardiology (E.J.B.), Medical College of Georgia, Augusta University
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Abstract
Perivascular adipose tissue (PVAT) refers to the local aggregate of adipose tissue surrounding the vascular tree, exhibiting phenotypes from white to brown and beige adipocytes. Although PVAT has long been regarded as simply a structural unit providing mechanical support to vasculature, it is now gaining reputation as an integral endocrine/paracrine component, in addition to the well-established modulator endothelium, in regulating vascular tone. Since the discovery of anti-contractile effect of PVAT in 1991, the use of multiple rodent models of reduced amounts of PVAT has revealed its regulatory role in vascular remodeling and cardiovascular implications, including atherosclerosis. PVAT does not only release PVAT-derived relaxing factors (PVRFs) to activate multiple subsets of endothelial and vascular smooth muscle potassium channels and anti-inflammatory signals in the vasculature, but it does also provide an interface for neuron-adipocyte interactions in the vascular wall to regulate arterial vascular tone. In this review, we outline our current understanding towards PVAT and attempt to provide hints about future studies that can sharpen the therapeutic potential of PVAT against cardiovascular diseases and their complications.
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Affiliation(s)
- Chak Kwong Cheng
- School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, SAR, China
- Institute of Vascular Medicine, Shenzhen Research Institute and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Hamidah Abu Bakar
- Health Sciences Department, Universiti Selangor, 40000, Shah Alam, Selangor, Malaysia
| | - Maik Gollasch
- Experimental and Clinical Research Center (ECRC)-a joint cooperation between the Charité-University Medicine Berlin and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), 13125, Berlin, Germany.
- Medical Clinic for Nephrology and Internal Intensive Care, Charité Campus Virchow Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.
| | - Yu Huang
- School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, SAR, China.
- Institute of Vascular Medicine, Shenzhen Research Institute and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, SAR, China.
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Oxidative and inflammatory signals in obesity-associated vascular abnormalities. Clin Sci (Lond) 2017; 131:1689-1700. [DOI: 10.1042/cs20170219] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/19/2017] [Accepted: 05/22/2017] [Indexed: 02/07/2023]
Abstract
Obesity is associated with increased cardiovascular morbidity and mortality in part due to vascular abnormalities such as endothelial dysfunction and arterial stiffening. The hypertension and other health complications that arise from these vascular defects increase the risk of heart diseases and stroke. Prooxidant and proinflammatory signaling pathways as well as adipocyte-derived factors have emerged as critical mediators of obesity-associated vascular abnormalities. Designing treatments aimed specifically at improving the vascular dysfunction caused by obesity may provide an effective therapeutic approach to prevent the cardiovascular sequelae associated with excessive adiposity. In this review, we discuss the recent evidence supporting the role of oxidative stress and cytokines and inflammatory signals within the vasculature as well as the impact of the surrounding perivascular adipose tissue (PVAT) on the regulation of vascular function and arterial stiffening in obesity. In particular, we focus on the highly plastic nature of the vasculature in response to altered oxidant and inflammatory signaling and highlight how weight management can be an effective therapeutic approach to reduce the oxidative stress and inflammatory signaling and improve vascular function.
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Lian X, Gollasch M. A Clinical Perspective: Contribution of Dysfunctional Perivascular Adipose Tissue (PVAT) to Cardiovascular Risk. Curr Hypertens Rep 2016; 18:82. [DOI: 10.1007/s11906-016-0692-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Even SEL, Dulak-Lis MG, Touyz RM, Nguyen Dinh Cat A. Crosstalk between adipose tissue and blood vessels in cardiometabolic syndrome: implication of steroid hormone receptors (MR/GR). Horm Mol Biol Clin Investig 2015; 19:89-101. [PMID: 25390018 DOI: 10.1515/hmbci-2014-0013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 08/06/2014] [Indexed: 11/15/2022]
Abstract
Crosstalk between adipose tissue and blood vessels is vital to vascular homeostasis and is disturbed in cardiovascular and metabolic diseases such as hypertension, diabetes and obesity. Cardiometabolic syndrome (CMS) refers to the clustering of obesity-related metabolic disorders such as insulin resistance, glucose and lipid profile alterations, hypertension and cardiovascular diseases. Mechanisms underlying these associations remain unclear. Adipose tissue associated with the vasculature [known as perivascular adipose tissue (PVAT)] has been shown to produce myriads of adipose tissue-derived substances called adipokines, including hormones, cytokines and reactive oxygen species (ROS), which actively participate in the regulation of vascular function and local inflammation by endocrine and/or paracrine mechanisms. As a result, the signaling from PVAT to the vasculature is emerging as a potential therapeutic target for obesity and diabetes-related vascular dysfunction. Accumulating evidence supports a shift in our understanding of the crucial role of elevated plasma levels of aldosterone in obesity, promoting insulin resistance and hypertension. In obesity, aldosterone/mineralocorticoid receptor (MR) signaling induces an abnormal secretion of adipokines, ROS production and systemic inflammation, which in turn contribute to impaired insulin signaling, reduced endothelial-mediated vasorelaxation, and associated cardiovascular abnormalities. Thus, aldosterone excess exerts detrimental metabolic and vascular effects that participate to the development of the CMS and its associated cardiovascular abnormalities. In this review, we focus on the physiopathological roles of corticosteroid receptors in the interplay between PVAT and the vasculature, which underlies their potential as key regulators of vascular function.
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Kurniawan ED, Cheung CY, Tay WT, Mitchell P, Saw SM, Wong TY, Cheung N. The relationship between changes in body mass index and retinal vascular caliber in children. J Pediatr 2014; 165:1166-1171.e1. [PMID: 25262303 DOI: 10.1016/j.jpeds.2014.08.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 06/30/2014] [Accepted: 08/18/2014] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To examine the longitudinal relationship between changes in childhood body mass index (BMI) and retinal vascular caliber. STUDY DESIGN A prospective study of 421 healthy children aged 7-9 years in 2001 who returned for follow-up in 2006. At both visits, retinal photographs and anthropometric measurements were taken following standardized protocols. Retinal arteriolar and venular calibers were measured using a computer-based program and summarized as central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE). RESULTS At follow-up, mean weight, height, and BMI increased significantly (P < .001). Mean CRVE increased by 3.4 μm (P < .001) but mean CRAE did not alter significantly (P = .340). On multivariate analysis, greater BMI was cross-sectionally associated with narrower CRAE (P < .01) and wider CRVE (P < .01). On longitudinal analysis, increasing BMI was associated with increasing CRVE (P = .04) over the 5-year period. Baseline BMI was associated with increased venular caliber and decreased arteriolar caliber at follow-up, and vice versa (P < .05). CONCLUSIONS Increasing BMI is associated with increasing retinal venular caliber over time in children, and baseline retinal vascular caliber changes increase the risk of higher BMI at follow-up. As both widened retinal venular caliber and greater BMI are associated with risk of cardiovascular events in adults, progressive retinal venular widening could be a manifestation of an adverse microvascular effect of obesity early in life.
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Affiliation(s)
- Emil D Kurniawan
- Center for Eye Research Australia, University of Melbourne, Melbourne, Australia
| | - Carol Y Cheung
- Singapore Eye Research Institute, Singapore National Eye Center, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Wan Ting Tay
- Singapore Eye Research Institute, Singapore National Eye Center, Singapore
| | - Paul Mitchell
- Center for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, Sydney, Australia
| | - Seang-Mei Saw
- Singapore Eye Research Institute, Singapore National Eye Center, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Tien Yin Wong
- Singapore Eye Research Institute, Singapore National Eye Center, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ning Cheung
- Singapore Eye Research Institute, Singapore National Eye Center, Singapore; Department of Ophthalmology, University of Hong Kong, Hong Kong SAR, China.
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Szasz T, Bomfim GF, Webb RC. The influence of perivascular adipose tissue on vascular homeostasis. Vasc Health Risk Manag 2013; 9:105-16. [PMID: 23576873 PMCID: PMC3616689 DOI: 10.2147/vhrm.s33760] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The perivascular adipose tissue (PVAT) is now recognized as an active contributor to vascular function. Adipocytes and stromal cells contained within PVAT are a source of an ever-growing list of molecules with varied paracrine effects on the underlying smooth muscle and endothelial cells, including adipokines, cytokines, reactive oxygen species, and gaseous compounds. Their secretion is regulated by systemic or local cues and modulates complex processes, including vascular contraction and relaxation, smooth muscle cell proliferation and migration, and vascular inflammation. Recent evidence demonstrates that metabolic and cardiovascular diseases alter the morphological and secretory characteristics of PVAT, with notable consequences. In obesity and diabetes, the expanded PVAT contributes to vascular insulin resistance. PVAT-derived cytokines may influence key steps of atherogenesis. The physiological anticontractile effect of PVAT is severely diminished in hypertension. Above all, a common denominator of the PVAT dysfunction in all these conditions is the immune cell infiltration, which triggers the subsequent inflammation, oxidative stress, and hypoxic processes to promote vascular dysfunction. In this review, we discuss the currently known mechanisms by which the PVAT influences blood vessel function. The important discoveries in the study of PVAT that have been made in recent years need to be further advanced, to identify the mechanisms of the anticontractile effects of PVAT, to explore the vascular-bed and species differences in PVAT function, to understand the regulation of PVAT secretion of mediators, and finally, to uncover ways to ameliorate cardiovascular disease by targeting therapeutic approaches to PVAT.
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Affiliation(s)
- Theodora Szasz
- Department of Physiology, Georgia Regents University, Augusta, GA, USA.
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Gombos RB, Brown JC, Teefy J, Gibeault RL, Conn KL, Schang LM, Hemmings DG. Vascular dysfunction in young, mid-aged and aged mice with latent cytomegalovirus infections. Am J Physiol Heart Circ Physiol 2012; 304:H183-94. [PMID: 23125213 DOI: 10.1152/ajpheart.00461.2012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Human cytomegalovirus (HCMV) is associated with vascular diseases in both immunosuppressed and immunocompetent individuals. CMV infections cycle between active and latent phases throughout life. We and others have shown vascular dysfunction during active mouse CMV (mCMV) infections. Few studies have examined changes in physiology during latent CMV infections, particularly vascular responses or whether the negative effects of aging on vascular function and fertility will be exacerbated under these conditions. We measured vascular responses in intact mesenteric and uterine arteries dissected from young, mid-aged, and aged latently mCMV-infected (mCMV genomes are present but infectious virus is undetectable) and age-matched uninfected mice using a pressure myograph. We tested responses to the α(1)-adrenergic agonist phenylephrine, the nitric oxide donor sodium nitroprusside, and the endothelium-dependent vasodilator methacholine. In young latently mCMV-infected mice, vasoconstriction was increased and vasodilation was decreased in mesenteric arteries, whereas both vasoconstriction and vasodilation were increased in uterine arteries compared with those in age-matched uninfected mice. In reproductively active mid-aged latently infected mice, mesenteric arteries showed little change, whereas uterine arteries showed greatly increased vasoconstriction. These vascular effects may have contributed to the decreased reproductive success observed in mid-aged latently mCMV-infected compared with age-matched uninfected mice (16.7 vs. 46.7%, respectively). In aged latently infected mice, vasodilation is increased in mesenteric and uterine arteries likely to compensate for increased vasoconstriction to mediators other than phenylephrine. The novel results of this study show that even when active mCMV infections become undetectable, vascular dysfunction continues and differs with age and artery origin.
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Affiliation(s)
- R B Gombos
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada
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Abstract
PVAT (perivascular adipose tissue) has recently been recognized as a novel factor in vascular biology, with implications in the pathophysiology of cardiovascular disease. Composed mainly of adipocytes, PVAT releases a wide range of biologically active molecules that modulate vascular smooth muscle cell contraction, proliferation and migration. PVAT exerts an anti-contractile effect in various vascular beds which seems to be mediated by an as yet elusive PVRF [PVAT-derived relaxing factor(s)]. Considerable progress has been made on deciphering the nature and mechanisms of action of PVRF, and the PVRFs proposed until now are reviewed here. However, complex pathways seem to regulate PVAT function and more than one mechanism is probably responsible for PVAT actions in vascular biology. The present review describes our current knowledge on the structure and function of PVAT, with a focus on its role in modulating vascular tone. Potential involvements of PVAT dysfunction in obesity, hypertension and atherosclerosis will be highlighted.
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Affiliation(s)
- Theodora Szasz
- Department of Physiology, Georgia Health Sciences University, Augusta, GA 30912, USA.
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Bunker AK, Laughlin MH. Influence of exercise and perivascular adipose tissue on coronary artery vasomotor function in a familial hypercholesterolemic porcine atherosclerosis model. J Appl Physiol (1985) 2009; 108:490-7. [PMID: 19959766 DOI: 10.1152/japplphysiol.00999.2009] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Our lab has shown that left circumflex coronary artery (LCX) perivascular adipose tissue (PAT) blunts endothelin-1 (ET-1)-induced maximal contractions in normal pigs on low- and high-fat diets. Other studies report that PAT exerts anticontractile effects on agonist-induced arterial contraction via release of a relaxing factor that acts on the underlying vasculature. The purpose of this study was to test the hypotheses that PAT blunts LCX contraction in familial hypercholesterolemic pigs and that exercise training (Ex) augments this anticontractile effect. Male familial hypercholesterolemic pigs were divided into Ex (n = 13) and sedentary (Sed) (n = 15) groups. LCX reactivity to angiotensin II (ANG II), bradykinin (BK), ET-1, and sodium nitroprusside (SNP) was evaluated in vitro with intact or removed PAT in Sed and Ex familial hypercholesterolemic pigs. LCX relaxation induced by BK and SNP was not altered by Ex or PAT removal. LCX contractions stimulated by ANG II and ET-1 were not significantly altered by Ex or PAT removal across doses; however, Ex did act to significantly reduce ET-1 maximal contractions in familial hypercholesterolemic pig LCX compared with Sed familial hypercholesterolemic pig LCX, independent of PAT (P < 0.05). We conclude that LCX PAT in Sed and Ex familial hypercholesterolemic pigs exerts no substantial anticontractile influence over LCX vasomotor responses to endogenous constrictors such as ANG II and ET-1. Our results suggest that exercise training significantly reduces familial hypercholesterolemic pig LCX maximal contractile responses to the endogenous constrictor ET-1, independent of PAT.
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Affiliation(s)
- Aaron K Bunker
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, 1600 East Rollins Rd., Columbia, MO 65211, USA
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Affiliation(s)
- Feng Zhang
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pa
| | - Suping Wang
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pa
| | | | - Jun Chen
- Departments of Neurology and Pharmacology, University of Pittsburgh, Pittsburgh, Pa, Geriatric Research, Educational and Clinical Center, VA Pittsburgh Health Care System, Pittsburgh, Pa
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