miR-27b-3p Down-Regulation Prevents Hypoxia-Induced Cardiomyocyte Apoptosis Through Regulating Yes-Associated Protein 1 (YAP1) Expression

Abstract

Background: Congenital heart disease (CHD) is one of the most common birth defects. MicroR-NAs (miRNAs) are a group of endogenous, non-coding small RNAs and mediate the target genes expression. An increasing evidence showed that in recent years, miRNAs have given rise to more and more attention in heart protection and development. In our research, the main purpose was to determine the effect of miR-27b-3p in CHD and analyze related mechanisms. Methods: We performed qRT-PCR analysis to examine miR-27b-3p expression in myocardial tissue from 30 patients with CHD and hypoxia-induced H9C2 cells. Then, we performed biological software TargetScan to predict the relationship of miR-27b-3p and YAP1, and dual luciferase reporter gene assay was used to verify the results. H9C2 cells were transfected with inhibitor control, miR-27b-3p inhibitor, miR-27b-3p inhibitor + control-siRNA or miR-27b-3p inhibitor + YAP1-siRNA for 6 hours and then induced by hypoxia for 72 hours. Subsequently, we performed MTT and FCM analysis to detect cell viability and apoptosis. Finally, we used western blot assay to measure the expression of apoptosis-related proteins. Results: Our study indicated that miR-27b-3p expression in myocardial samples of cyanotic CHD patients was significantly higher than that of the acyanotic CHD patients. miR-27b-3p expression was gradually up-regulated with the increase of hypoxia induction time in H9C2 cells. Besides, we confirmed that YAP1 was a target gene of miR-27b-3p. Moreover, our results showed that miR-27b-3p inhibitor improved cell viability, decreased apoptosis, and affected apoptosis-related proteins expression in hypoxia induced H9C2 cells. These changes were reversed by YAP1-siRNA. All data demonstrated that miR-27b-3p/YAP1 might be new potential bio-marker and therapeutic target for CHD treatment.