MicroRNA-25 Negatively Regulates Cerebral Ischemia/Reperfusion Injury-Induced Cell Apoptosis Through Fas/FasL Pathway

MicroRNA-25 (miR-25) has been reported to be a major miRNA marker in neural cells and is strongly expressed in ischemic brain tissues. However, the precise mechanism and effect of miR-25 in cerebral ischemia/reperfusion (I/R) injury needs further investigations. In the present study, the oxygen-glucose deprivation (OGD) model was constructed in human SH-SY5Y and IMR-32 cells to mimic I/R injury and to evaluate the role of miR-25 in regulating OGD/reperfusion (OGDR)-induced cell apoptosis. We found that miR-25 was downregulated in the OGDR model. Overexpression of miR-25 via miRNA-mimics transfection remarkably inhibited OGDR-induced cell apoptosis. Moreover, Fas was predicted as a target gene of miR-25 through bioinformatic analysis. The interaction between miR-25 and 3'-untranslated region (UTR) of Fas mRNA was confirmed by dual-luciferase reporter assay. Fas protein expression was downregulated by miR-25 overexpression in OGDR model. Subsequently, the small interfering RNA (siRNA)-mediated knockdown of Fas expression also inhibited cell apoptosis induced by OGDR model; in contrast, Fas overexpression abrogated the protective effects of miR-25 on OGDR-induced cells. Taken together, our results indicate that the upregulation of miR-25 inhibits cerebral I/R injury-induced apoptosis through downregulating Fas/FasL, which will provide a promising therapeutic target.