MiRNA-615-3p Alleviates Oxidative Stress Injury of Human Cardiomyocytes Via PI3K/Akt Signaling by Targeting MEF2A.

BACKGROUND

Myocardial infarction, a coronary heart disease, is a serious hazard to human health. Cardiomyocyte oxidative stress and apoptosis have been considered as the main causes of myocardial infarction. Here, we aimed to investigate the role of miR-615-3p in oxidative stress and apoptosis of human cardiomyocytes.

METHODS

Reverse transcription-quantitative polymerase chain reaction was performed to determine miR-615-3p or MEF2A expression in human cardiomyocytes. Apoptosis and viability of human cardiomyocytes were assessed by flow cytometry analysis and CCK-8 assay. In addition, the contents of malondialdehyde, reactive oxygen species, and superoxide dismutase were detected by corresponding commercial kits. The binding of miR-615-3p and MEF2A in human cardiomyocytes was examined by luciferase reporterassay.

RESULTS

Hypoxia/reoxygenation treatment downregulated the expression level ofmiR-615-3p in human cardiomyocytes. Overexpressing miR-615-3p increased human cardiomyocyte viability and decreased human cardiomyocyte apoptosis. Moreover, miR- 615-3p mimics suppressed oxidative stress in hypoxia/reoxygenation-stimulated human cardiomyocytes. MEF2A was confirmed as a target gene of miR-615-3p and was highly expressed in hypoxia/reoxygenation-stimulated human cardiomyocytes, and its upregu-lation partially reversed the influence of miR-615-3p mimics on oxidative stress and apop-tosis of human cardiomyocytes. Moreover, miR-615-3p inactivated the P13K/Akt pathway by inhibiting MEF2A.

CONCLUSIONS

Overexpression of miR-615-3p protects human cardiomyocytes from oxida-tive stress injury by targeting MEF2A via the PI3K/Akt signaling.