Study on the mechanism of miRNA-26a inhibiting ox-LDL-mediated apoptosis of HAECs / 重庆医学

ABSTRACT

Objective To investigate the role of miR‐26a in ox‐LDL‐mediated apoptosis of HAECs in endothelial cells and its mechanism .Methods Various concentrations of ox‐LDL were added in HAECs culture .Cell cytotoxicity and apoptosis were moni‐tored by MTT and TUNEL assay ,and expression level of miR‐26a examined by qRT‐PCR .Overexpression of miR‐26a mimic in HAECs ,MTT and TUNEL staining were used to detect the activity and apoptosis of ox‐LDL .The 3′UTR of luciferase reporter vector pMIR‐PTEN was constructed and the predicted target gene of miR‐26a was identified by luciferase activity assay .QRT‐PCR and Western blot were used to detect the mRNA and protein expression of PTEN .Results ox‐LDL could mediate the toxic death and apoptosis of HAECs cells ,and decrease the expression level of miR‐26a in HAECs cells .Overexpression of miR‐26a mimic could inhibit the cytotoxicity and apoptosis of ox‐LDL cells after HAECs .Transfection of miR‐26a mimics significantly inhibited lu‐ciferase activity (P<0 .05) .The expression of mRNA and protein in HAECs cells was significantly down regulated by transfection of miR‐26a analog (P<0 .05) .Conclusion MiR‐26a can inhibit the cytotoxicity and apoptosis of ox‐LDL cells after HAECs inhibi‐tion ,and the possible mechanism of action is to down regulate the expression of PTEN .The study suggests that miR‐26a may be a potential target for the treatment of atherosclerosis related to apoptosis .