Abstract
Traditionally, it is believed that white adipose tissues serve as energy storage, heat insulation, and mechanical cushion, whereas non-shivering thermogenesis occurs in brown adipose tissue. Recent evidence revealed that adipose tissue secretes many types of cytokines, called as adipocytokines, which modulate glucose metabolism, lipid profile, appetite, fibrinolysis, blood pressure, and inflammation. Most of the arteries are surrounded by perivascular adipose tissue (PVAT). PVAT has been thought to be simply a structurally supportive tissue for vasculature. However, recent studies showed that PVAT influences vasodilation and vasocontraction, suggesting that PVAT regulates vascular tone and diameter. Adipocytokines secreted from PVAT appear to have direct access to the adjacent arterial wall by diffusion or via vasa vasorum. In fact, PVAT around atherosclerotic lesions and mechanically-injured arteries displayed inflammatory cytokine profiles, suggesting that PVAT functions to promote vascular lesion formation. Many clinical studies revealed that increased accumulation of epicardial adipose tissue (EAT), which surrounds coronary arteries, is associated with coronary artery disease. In this review article, we will summarize recent findings about potential roles of PVAT in the pathogenesis of atherosclerosis, particularly focusing on a series of basic and clinical studies from our laboratory.
Highlights
Reviewed by: Irena Levitan, University of Illinois at Chicago, United States Klaus Ley, La Jolla Institute for Allergy and Immunology (LJI), United States
In the patients undergoing coronary artery bypass graft (CABG) surgery, it was reported that epicardial adipose tissue (EAT) abundantly expressed interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and monocyte chemoattractant protein-1 (MCP-1) compared to their subcutaneous adipose tissue (Mazurek et al, 2003)
The ratio of M1/M2 macrophages showed positive correlation with the severity of coronary artery disease (CAD) as determined by Gensini score (Gensini, 1983). These results suggested that the chronic inflammation and macrophage polarization in EAT would play a pathological role in human coronary atherosclerosis
Summary
Many clinical studies revealed that increased accumulation of epicardial adipose tissue (EAT), which surrounds coronary arteries, is associated with coronary artery disease. Analyses of human samples showed that PVAT around the coronary arteries, like other adipose tissues, expresses inflammatory cytokines, and chemokines (Mazurek et al, 2003; Henrichot et al, 2005). We evaluated whether inflammation in PVAT affects the lesion formation after a mechanical vascular injury in murine femoral artery (Takaoka et al, 2009) (Figure 2).
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call