Abstract
Objective: Factors released by perivascular adipose tissue (PVAT) disrupt coronary endothelial function via phosphorylation of endothelial NO synthase by protein kinase C (PKC)-β. However, our understanding of how PVAT potentially contributes to coronary disease as a complication of obesity/metabolic syndrome (MetS) remains limited. The current study investigated whether PVAT-derived leptin impairs coronary vascular function via PKC-β in MetS. Methods and Results: Coronary arteries with and without PVAT were collected from lean or MetS Ossabaw miniature swine for isometric tension studies. Endothelial-dependent vasodilation to bradykinin was significantly reduced in MetS. PVAT did not affect bradykinin-mediated dilation in arteries from lean swine but significantly exacerbated endothelial dysfunction in arteries from MetS swine. PVAT-induced impairment was reversed by inhibition of either PKC-β with ruboxistaurin (Eli Lilly and Company, Indianapolis, Ind) or leptin receptor signaling with a recombinant, pegylated leptin antagonist. Western blot and immunohistochemical analyses demonstrated increased PVAT-derived leptin and coronary leptin receptor density with MetS. Coronary PKC-β activity was increased in both MetS arteries exposed to PVAT and lean arteries exposed to leptin. Finally, leptin-induced endothelial dysfunction was reversed by ruboxistaurin. Conclusion: Increases in epicardial PVAT leptin exacerbate coronary endothelial dysfunction in MetS via a PKC-β-dependent pathway. These findings implicate PVAT-derived leptin as a potential contributor to coronary atherogenesis in MetS.
Original language | English |
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Pages (from-to) | 1711-1717 |
Number of pages | 7 |
Journal | Arteriosclerosis, Thrombosis, and Vascular Biology |
Volume | 30 |
Issue number | 9 |
DOIs | |
State | Published - Sep 2010 |
Keywords
- coronary artery disease
- endothelium
- epicardial perivascular adipose tissue
- obesity