Epicardial Adipose Tissue as a Source of Nuclear Factor-B and c-Jun N-Terminal Kinase Mediated Inflammation in Patients with Coronary Artery Disease

Context: Visceral adipose tissue (AT) is known to confer a significantly higher risk of type 2 diabetes and cardiovascular disease. Epicardial AT has been shown to be related to cardiovascular disease and myocardial function through unidentified mechanisms. Epicardial AT expresses an inflammatory profile of proteins; however, the mechanisms responsible are yet to be elucidated. Objectives: The objectives of the study were to: 1) examine key mediators of the nuclear factor-B (NFB) and c-Jun N-terminal kinase (JNK) pathways in paired epicardial and gluteofemoral (thigh) AT from coronary artery disease (CAD) and control patients and 2) investigate circulating endotoxin levels in CAD and control subjects. Design: Serums and AT biopsies (epicardial and thigh) were obtained from CAD (n = 16) and non-CAD (n = 18) patients. Inflammation was assessed in tissue and serum samples through Western blot, real-time PCR, ELISAs, and activity studies. Results: Western blotting showed epicardial AT had significantly higher NFB, inhibitory-B kinase (IKK)-, IKKβ, and JNK-1 and -2 compared with thigh AT. Epicardial mRNA data showed strong correlations between CD-68 and toll-like receptor-2, toll-like receptor-4, and TNF-. Circulating endotoxin was elevated in patients with CAD compared with matched controls [CAD: 6.80 ± 0.28 endotoxin unit(EU)/ml vs. controls: 5.52 ± 0.57 EU/ml; P