Inhibition of miR-302 Suppresses Hypoxia-Reoxygenation-Induced H9c2 Cardiomyocyte Death by Regulating Mcl-1 Expression.

Abstract

MicroRNAs play important roles in cell proliferation, differentiation, and apoptosis, and their expression influences cardiomyocyte apoptosis resulting from ischemia-induced myocardial infarction. Here, we determined the role of miR expression in cardiomyocyte apoptosis during hypoxia and reoxygenation. The rat cardiomyocyte cell line H9c2 was incubated for 3 h in normal or hypoxia medium, followed by reoxygenation for 24 h and transfection with a miR-302 mimic or antagomir. The effect of miR-302 on myeloid leukemia cell-differentiation protein-1 (Mcl-1) expression was determined by western blot, real-time polymerase chain reaction, and luciferase reporter assays, with cell viability assays. We observed that miR-302 expression was elevated by hypoxia/reoxygenation injury and increased further or decreased by transfection of the miR-302 mimic or miR-302 antagomir, respectively. Additionally, elevated miR-302 levels increased apoptosis-related protein levels and cardiomyocyte apoptosis, and luciferase reporter assays revealed miR-302 binding to the Mcl-1 mRNA 3' untranslated region. Our findings suggested that miR-302 overexpression aggravated hypoxia/reoxygenation-mediated cardiomyocyte apoptosis by inhibiting antiapoptotic Mcl-1 expression, thereby activating proapoptotic molecules. Furthermore, results indicating cardiomyocyte rescue from hypoxia/reoxygenation injury following treatment with miR-302 antagomir suggested that miR-302 inhibition might constitute a therapeutic strategy for protection against cardiomyocyte apoptosis during hypoxia/reoxygenation injury.

• Authors: Yao-Ching Fang, Chi-Hsiao Yeh
• Journal: Oxidative medicine and cellular longevity (Oxid Med Cell Longev) Vol. 2017 Pg. 7968905 ( 2017) ISSN: 1942-0994 [Electronic] United States
• PMID: 28491238 (Publication Type: Journal Article)

Chemical References

• Mcl1 protein, rat
• MicroRNAs
• Myeloid Cell Leukemia Sequence 1 Protein

Topics

• Animals
• Apoptosis
• Cell Hypoxia
• Cell Line
• Gene Expression Regulation
• MicroRNAs (antagonists & inhibitors, metabolism)
• Myeloid Cell Leukemia Sequence 1 Protein (biosynthesis)
• Myocardial Reperfusion Injury (metabolism, pathology, prevention & control)
• Myocytes, Cardiac (metabolism, pathology)
• Rats