MiR-31a-5p aggravates apoptosis in myocardial ischemia by targeting HIF-1α
Objective To investigate the expression of miR-31a-5p in myocardial infarction(MI)mice and its potential mechanism.Methods A dataset was downloaded from the gene expression database,and miR-31a-5p and its predicted target gene hypoxia-inducible factor-1α(HIF-1α)were screened using bioinformatics methods.The MI model was established by ligating the left anterior descending branch of the coronary artery in C57BL/6J male mice which were randomly divided into sham and MI groups(n=6 in each group).The in vitro hypoxic cell model was induced by treatment of H9c2 cells with cobalt chloride(CoCI2)and divided into a control group,a model group,a NC group,a miR-31a-5p mimic group and a miR-31a-5p inhibitor group.The degree of myocardial tissue fibrosis was stained by Masson and analyzed.The expression levels of miR-31a-5p and HIF-1α mRNA in mouse myocardial tissues and H9c2 cells were detected by qRT-PCR.Western blotting was used to detect the expression levels of B-cell lymphoma 2(Bcl-2),cleaved-caspase 3 apoptotic protein in mouse myocardial tissues and HIF-1α and apoptotic protein in H9c2 cells,respectively.The dual luciferase reporter gene assay was used to verify the targeting relationship between miR-31a-5p and HIF-1α.Results Masson staining showed significantly increased fibrosis in MI mice(P＜0.000 1);miR-31a-5p,cleaved-caspase 3 were significantly elevated and Bcl-2 was decreased in MI mice and CoCl2 treated H9c2(P＜0.05).The results of dual luciferase reporter assay showed that the relative luciferase activity of miR-31a-5p mimic cotransfected with HIF-1α-3'-UTR WT plasmid was reduced(P＜0.000 1);miR-31a-5p mimic decreased HIF-1α expression and increased apoptotic protein levels in CoCl2 induced H9c2 cells(both P＜0.05),while miR-31a-5p exerted the opposite effect.Conclusion miR-31a-5p can aggravate apoptosis in myocardial ischemia by targeting HIF-1α.
MiR-31a-5pcardiomyocyteshypoxia-inducible factor-1αmyocardial hypoxiaapoptosisexperimental study
万方数据
维普
