Effect of α-lipoic acid in inhibiting the expression of intercellular adhesion molecule-1 in human umbilical vein endothelial cells under high glucose concentration

Objective To investigate the effect of α-lipoic acid on the expression levels of intercellular adhesion molecule-1 (ICAM-1) in human umbilical vein endothelial cells under high glucose concentration. Methods Human umbilical vein endothelial cells (ECV304) were randomized into control (NG) group,high glucose (HG) group and α-lipoic acid group. Cells in the 3 groups were incubated for 48h with 5.5mmol/L glucose,30mmol/L glucose,30mmol/L glucose + α-lipoic acid in a series of concentrations (50,100,200μmol/L),respectively. The activity of superoxide dismutase (SOD) in the supernate was determined by the method of xanthine oxidase,and the content of malondialdehyde (MDA) was measured with thiobarbituric acid as the substrate. The level of ICAM-1 in the supernate was determined by enzyme-linked immunosorbent assay (ELISA). The expressive levels of ICAM-1 mRNA were determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Results Compared with the control group,the activity of SOD declined significantly and the contents of MDA and ICAM-1 increased in umbilical vein endothelial cells in HG group (P0.01); the expressive levels of ICAM-1 mRNA in endothelial cells increased markedly in HG group (P0.01). However,when endothelial cells incubated with 30mmol/L glucose were treated by α-lipoic acid,the activity of SOD increased (P0.01),the contents of MDA and ICAM-1 decreased (P0.01),and the expressive levels of ICAM-1 mRNA were reduced significantly (P0.05). Conclusions α-lipoic acid can amend oxidative stress status and inhibit the expression of ICAM-1 in vascular endothelial cell under high glucose concentration.