Effect of miR-497 on myocardial cell apoptosis in rats with myocardial ischemia/reperfusion through the MAPK/ERK signaling pathway.

OBJECTIVE: The aim of this study was to investigate the effect of micro ribonucleic acid (miR)-497 on myocardial cell apoptosis in rats with myocardial ischemia/reperfusion (I/R) through the mitogen-activated protein kinase (MAPK)/extracellular regulated protein kinase (ERK) signaling pathway. MATERIALS AND METHODS: A rat model of myocardial I/R was established, myocardial cells were extracted, and miR-497 was inhibited by inhibitors and overexpressed using miRNA mimics. The cell apoptosis rate was detected by flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The interaction between miR-497 and ERK was determined by dual-luciferase reporter gene assay. The change in the protein level was measured via Western blotting (WB). RESULTS: Up-regulation of miR-497 promoted myocardial cell apoptosis, and the 3'-untranslated region (3'-UTR) of ERK was highly conserved to combine with miR-497. The luciferase reporter gene assay showed that the transfection of miR-497 could significantly inhibit the relative luciferase activity in cells. CONCLUSIONS: MiR-497 overexpression significantly down-regulated the ERK expression at messenger RNA (mRNA) and protein levels in cells. MiR-497 plays an important role in regulating I/R injury-induced myocardial cell apoptosis by targeting the ERK-induced apoptosis pathway.