Date of Degree
MS (Master of Science)
Health and Human Physiology
Gary L. Pierce
Obesity is associated with chronic inflammation and increased risk of developing cardiovascular disease (CVD). Obesity is also associated with nitric oxide (NO)-mediated vascular endothelial dysfunction (VED), an independent predictor of increased CVD risk in humans. Pro-inflammatory cytokines secreted by the adipose tissue, such as TNF-Α, may contribute to VED through promotion of insulin resistance or directly through a reduction in endothelial NO synthase (eNOS) expression and/or phosphorylation. Sodium salicylate (Na-Sal) is a non-acetylated aspirin that inhibits the pro-inflammatory transcription factor nuclear factor-ΚB (NF-ΚB) and activates the cellular metabolism regulator AMP-activated protein kinase (AMPK). AMPK is a known activator of eNOS. We tested the hypothesis that Na-Sal increases eNOS expression/phosphorylation in TNFΑ-stimulated endothelial cells through an AMPK-dependent mechanism. Human aortic endothelial cells (HAECs) incubated in vitro with TNF-Α (10 ng/ml, 2 hrs) demonstrated decreased (vs. control) expression (via Western blotting) of eNOSser1177 phosphorylation (n=8; PThr172 phosphorylation (n=8, Pser1177 phosphorylation (vs. control, n=7; P=0.14) and AMPKThr172 phosphorylation (vs. control, n=9; P=0.42). The AMPK activator AICAR prevented eNOSser1177 phosphorylation down-regulation by TNF-Α in a manner similar to Na-Sal (n=2, P=0.839). Co-treatment with the AMPK inhibitor compound C (10 μM, 30 min) abolished the ability of Na-Sal to prevent down-regulation of eNOSser1177 phosphorylation by TNF-Α (vs. control, n=3; Pser1177 in endothelial cells in part through AMPK.
AMP Activated Protein Kinase, Endothelial Dysfunction, endothelial Nitric Oxide Synthase, Nuclear Factor- kappa β, P65, Sodium Salicylate
ix, 60 pages
Includes bibliographical references (pages 51-60).
Copyright 2014 Kyle John Siefers