Study on the mechanism of long non-coding RNA NUTM2A-AS1 targeting microRNA-129-5p in regulating oxidized low density lipoprotein-induced vascular endothelial cell damage

Objective To explore the effect of long non-coding RNA (lncRNA) NUTM2A-AS1 on the damage of vascular endothelial cells induced by oxidized low density lipoprotein (oxLDL) and its molecular mechanism.

Methods Human umbilical vein endothelial cells(HUVECs) were cultured in DMEM medium. The HUVECs treated with 100 μg/mL oxLDL were assigned to oxLDL group, while those cultured under normal conditions were assigned to Con group. After transfection of the lncRNA NUTM2A-AS1 interference expression vector and negative control, microRNA-129-5p mimic and negative control into HUVECs, the cells treated with 100 μg/mL oxLDL were assigned to oxLDL+si-NUTM2A-AS1 group, oxLDL+si-NC group, oxLDL+miR-129-5p group, and oxLDL+miR-NC group, respectively. After co-transfection of the lncRNA NUTM2A-AS1 interference expression vector and miR-129-5p inhibitor or negative control into HUVECs, the cells treated with 100 μg/mL oxLDL were assigned to oxLDL+si-NUTM2A-AS1+anti-miR-129-5p group and oxLDL+si-NUTM2A-AS1+anti-miR-NC group. The levels of malondialdehyde (MDA) in cells, as well as the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured using kits. Cell apoptosis was detected by flow cytometry. Protein expression was detected by Western blot. The targeting relationship between NUTM2A-AS1 and miR-129-5p was detected by dual luciferase reporter assay and RNA pull-down experiments.

Results Compared with the Con group, the expression level of lncRNA NUTM2A-AS1 was increased, the expression level of miR-129-5p was decreased, the content of MDA was increased, the activities of SOD and GSH-Px were decreased, the apoptosis rate of vascular endothelial cells and the expression levels of cleaved-caspase3 and cleaved-caspase9 were increased in the oxLDL group (P < 0.05). After interference of lncRNA NUTM2A-AS1 expression or overexpression of miR-129-5p, the content of MDA was decreased, the activities of SOD and GSH-Px were increased, cell apoptosis was reduced (P < 0.05). The damage to vascular endothelial cells mediated by knockdown of lncRNA NUTM2A-AS1 under oxLDL conditions can be reversed by downregulation of miR-129-5p. LncRNA NUTM2A-AS1 targeted miR-129-5p for regulation.

Conclusion Interference of lncRNA NUTM2A-AS1 expression can inhibit oxLDL-induced vascular endothelial cell damage by targeting miR-129-5p for upregulation.