ARL15 overexpression attenuates high glucose-induced impairment of insulin signaling and oxidative stress in human umbilical vein endothelial cells.

AIMS: Endothelial dysfunction (ED) plays a pivotal role in the development and progression of cardiovascular disease. Recently, genomic studies have found that ARL15, and some of its common genetic variants are associated with type 2 diabetes and coronary atherosclerosis. Since, the function of ARL15 is unclear we aimed at investigating the role of ARL15 in ED induced by high glucose (HG) in human umbilical vein endothelial cells (HUVECs).

MAIN METHODS: Quantitative real-time PCR was used to access the mRNA expression of ARL15. After exposure to different glucose media, nitric oxide (NO) production and the levels of superoxide dismutase (SOD), malondialdehyde (MDA), and reactive oxygen species (ROS) were studied. The underlying signaling pathway was also examined by western blot.

KEY FINDINGS: Up-regulation of ARL15 attenuates HG-induced impairment in HUVECs. With insulin-stimulation, NO production and the active phosphorylation of the IR/IRS1/AKT/eNOS pathway were significantly increased. ARL15 overexpression was found to decrease the ROS and MDA production and increase SOD level. It could also reduce ERK1/2-Thr183-Tyr185 phosphorylation, NOX2 and NOX4 expression in HG medium.

SIGNIFICANCE: These results suggest that ARL15 could significantly alleviate the dysfunction of HUVECs induced by HG. Our findings help to identify new potential protective effects of ARL15 in HG-induced endothelial impairment.