miRNA‐145‐5p induces apoptosis after ischemia‐reperfusion by targeting dual specificity phosphatase 6

Disorders mainly caused by ischemia‐reperfusion (I/R), including stroke and myocardial infarction, is linked to debilitating health conditions and death. Recent research indicates that microRNAs (miRNAs) mediate the process of ischemic pathology. This study investigated the effects of miR‐145‐5p in regulating myocardial ischemic injury. The I/R models were established in rat cardiomyocytes H9C2 and rats. Western blot analysis and quantitative polymerase chain reaction was performed to analyze protein expression. Annexin V‐FITC/PI staining was conducted to evaluate cell apoptosis. The application of miR‐145‐5p mimics and inhibitor revealed that miR‐145‐5p promoted apoptosis in cardiomyocytes. Furthermore, we found that miR‐145‐5p directly inhibited dual specificity phosphatase 6 (DUSP6) by luciferase reporter assay. The results indicated that DUSP6 was beneficial against I/R injury through inhibiting c‐Jun N‐terminal kinase pathways. In conclusion, the essential roles of miR‐145‐5p and DUSP6 in I/R provide a novel therapeutic target to develop future intervention strategies. miR‐145‐5p negatively regulated dual specificity phosphatase 6 (DUSP6) expression after ischemia‐reperfusion (I/R) both in vitro and in vivo, and further activated mitogen‐activated protein kinases signaling for apoptosis. Inhibiting miR‐145‐5p actions can have protective effects after I/R in cardiomyocytes.