MiR-195 enhances cardiomyocyte apoptosis induced by hypoxia/reoxygenation injury via downregulating c-myb

• Published in: European review for medical and pharmacological sciences Vol. 20; no. 16; p. 3410
• Main Authors: Chen, C, Jia, K-Y, Zhang, H-L, Fu, J
• Format: Journal Article
• Language: English
• Published: Italy 01.08.2016
• Subjects: Apoptosis - genetics; Caspase 3 - metabolism; Cell Hypoxia; MicroRNAs - genetics; Myocytes, Cardiac - metabolism; Myocytes, Cardiac - pathology; Proto-Oncogene Proteins c-myb - metabolism
• ISSN: 2284-0729

In this study, we explored the regulative effect of miR-195 on c-myb expression and also investigated the role of miR-195 and c-myb in cardiomyocyte apoptosis induced by hypoxia/reoxygenation (H/R) injury. QRT-PCR analysis was performed to measure mature miR-195 expression. H9c2 cells were transfected for miR-195 overexpression or knockdown or c-myb overexpression using Lipofectamine 2000. The cells were subjected to H/R treatment and following flow cytometric analysis of active caspase-3 or florescent study of reactive oxygen species (ROS) generation. The binding sites between miR-195 and 3'UTR of MYB mRNA were predicted using TargetScan 7.0. The binding sites were verified using dual luciferase assay and Western blot analysis. MiR-195 is significantly upregulated after H/R treatment in H9c2 cells. H/R injury induced active caspase-3 expression. However, the cells with miR-195 suppression had substantially lower ratio of cells with active caspase-3. MiR-195 can decrease c-myb protein expression. Dual luciferase assay verified two binding sites between miR-195 and 3'UTR of MYB mRNA. C-myb overexpression can suppress mitochondrial superoxide generation and cardiomyocyte apoptosis after H/R. MiR-195 is significantly increased due to H/R and can enhance cardiomyocyte apoptosis. MYB is a target gene of miR-195 in cardiomyocytes. The miR-195-MYB axis is involved in regulation of cardiomyocyte apoptosis induced by H/R.