Effect of Hyperglycemia on eNOS function in EPCs

Abstract

Type 2 diabetes mullites (T2DM) results in different cardiovascular complications. The main cause of these complications is endothelial dysfunction, which affects the endothelium physiologically and pathologically. The chronic hyperglycemia introduced by T2DM impacts the pivotal enzyme endothelial nitric oxide synthase (eNOS) in terms of phosphorylation and dimerization, which initiates oxidative stress and reduces the bioavailability of the vasodilator nitric oxide. To overcome endothelial dysfunction, endothelial progenitor cells (EPCs) contribute to vascular repair due to their regenerative characteristics. The effects of hyperglycemia on EPCs are understudied. Thus, this study aims to investigate the effects of hyperglycemia on the eNOS/Akt signaling pathway and reactive oxygen species (ROS) formation. Cells were treated with normal glucose (NG, 5.5mM) and high glucose (HG, 25mM) media for 3 & 6 days, and the effect on eNOS and Akt phosphorylation were assessed using western blot. ROS was assessed using CellROX stain following 1 and 3 days of treatment. Results showed that both acute and chronic hyperglycemia showed a trend towards decrease in phosphorylation of eNOS and Akt. In addition, ROS formation was increased following 24hr compared to NG. Further investigations are needed to enhance the capability of BOECs to serve as therapeutic tools in T2DM