miR-133a mediates Bcl-xl expression to regulate endothelial cell apoptosis / 医学研究生学报

ABSTRACT

ObjectiveThe specific mechanism of microRNA-133a (miR-133a) involved in the pathological process of atherosclerosis (As) remains an open question. This study aims to explore the role of miR-133a in the regulation of endothelial cell apoptosis.MethodsCultured human coronary endothelial cells (HCAECs) were treated with oxidized low density lipoprotein (ox-LDL). The cell viability was detected by MTT assay. The mRNA levels of Bcl-xl and miRNA (miR-133a, etc) were detected by qRT-PCR method. The expression of anti-apoptotic protein Bcl-xl and cleaved-caspase3 was detected by Western blotting, and the apoptosis rate was detected by flow cytometry. The transient transfection technique was used to observe the effect of overexpression and silencing of miR-133a, on the expression of target gene Bcl-xl protein and endothelial cell apoptosis.Results Ox-LDL was observed to decrease the viability of HCAECs cells and induce HCAECs apoptosis; miR-133a increased abnormally in the apoptosis model; after silencing miR-133a, the decrease of Bcl-xl and the increase of apoptosis rate induced by ox-LDL were partially reversed; the overexpression of miR-133a, Bcl-xl decreased and the apoptosis rate increased, and the difference was statistically significant.Conclusion miR-133a might target and regulate the anti-apoptotic protein Bcl-xl, to induce endothelial cell apoptosis and promote the formation of AS.