摘要
Abstract
Objective To investigate the effects of circTLK1 targeting microRNA(miR)-424-5p on oxidized low-density lipoprotein(ox-LDL)-induced injury in human coronary artery endothelial cells(HCAECs).Methods HCAECs were exposed to ox-LDL to induce HCAECs injury(incubated with 80 μg/mL ox-LDL for 24 hours).HCAECs co-incubated with ox-LDL for 24 hours were set as the ox-LDL group,while the non-incubated ones were set as the con group.HCAECs were transfected with si-NC,si-TLK1,miR-NC,and miR-424-5p mimic,respectively,and then co-incubated with ox-LDL for 24 hours,forming the ox-LDL+si-NC group,ox-LDL+si-TLK1 group,ox-LDL+miR-NC group,and ox-LDL+miR-424-5p mimic group.HCAECs were transfected with si-TLK1 and anti-miR-NC combination,as well as si-TLK1 and miR-424-5p inhibitor combination,respectively,and then co-incubated with ox-LDL for 24 hours,forming the ox-LDL+si-TLK1+anti-miR-NC group and ox-LDL+si-TLK1+miR-424-5p inhibitor group.HCAECs proliferation inhibition rate was measured using cell counting kit-8 assay.HCAECs apoptosis rate was determined by flow cytometry.Cellular oxidative stress damage was evaluated by detecting the activity of superoxide dismutase(SOD)and the level of malondialdehyde(MDA).The targeted relationship between circTLK1 and miR-424-5p was confirmed by dual luciferase reporter experiment.Results Compared with the con group,the proliferation inhibition rate,apoptosis rate,circTLK1 expression,and MDA level in the ox-LDL group increased(P<0.05),while miR-424-5p expression and SOD activity decreased,the differences were all statistically significant(P<0.05).Knockdown of circTLK1 or miR-424-5p over-expression could block the inhibition of cell proliferation and the promotion of cell apoptosis due to ox-LDL-induced HCAECs injury,as well as high MDA expression and low SOD expression(P<0.05).Knockdown of circTLK1 up-regulated miR-424-5p expression in ox-LDL-induced HCAECs(P<0.05).circTLK1 contained complementary sequences to miR-424-5p.Compared with the ox-LDL+si-TLK1+anti-miR-NC group,the proliferation inhibition rate,apoptosis rate,and MDA level in HCAECs in the ox-LDL+si-TLK1+miR-424-5p inhibitor group increased,while SOD activity decreased,the differences were all statistically significant(t=27.515,12.061,24.015,21.007;P<0.05).Conclusion Down-regulation of circTLK1 alleviates ox-LDL-induced apoptosis and oxidative stress damage in HCAECs by targeted promoting miR-424-5p expression.关键词
动脉粥样硬化/冠状动脉内皮细胞/凋亡/氧化型低密度脂蛋白Key words
Atherosclerosis/Coronary artery endothelial cells/Apoptosis/Oxidized low-density lipoprotein
