Asiatic acid enhances survival of human AC16 cardiomyocytes under hypoxia by upregulating miR-1290.

Asiatic acid (AA) could attenuate ischemia/reperfusion induced myocardial apoptosis through upregulating the Akt/GSK-3β/HIF-1α pathway. HIF-3α is a negative regulator of HIF-1α, whose mRNA is a potential target of miR-1290. AA could upregulate miR-1290 in non-small-cell lung cancer A549 cells. This work aimed to investigate whether AA could inhibit hypoxia induced cardiomyocyte apoptosis through regulating the miR-1290/HIF3A/HIF-1α axis. The AC16 human myocardial cell line cultured under normoxic or hypoxic conditions was treated with various doses of AA for 24 h. Afterwards cell viability, apoptosis and the expression of miR-1290, HIF3A, and HIF1A were evaluated. Cells transfected with miR-1290 mimic or inhibitor were used to determine the role of miR-1290 in the anti-apoptosis effect of AA and the expression of HIF3A and HIF1A. Dual luciferase assay was performed to confirm miR-1290 targeting of HIF3A. HIF3A overexpression was achieved by transfection of HIF3A1 overexpressing lentivirus, and its effect on miR-1290 and AA-regulated survival of cardiomyocytes was evaluated. AA treatment protected cardiomyocytes from hypoxia-induced apoptosis and upregulated miR-1290 and HIF1A, but downregulated HIF3A under hypoxia. The protective effect of AA was abolished by miR-1290 knockdown, whereas enhanced by miR-1290 overexpression. In addition, miR-1290 knockdown increased HIF1A expression, but reduced HIF3A expression in cardiomyocytes. Dual luciferase assay confirmed miR-1290 direct targeting the 3' UTR of HIF3A. HIF3A overexpression counteracted the anti-apoptosis effect of AA or miR-1290. In conclusion, AA can protect cardiomyocytes against hypoxia-induced apoptosis through regulating the miR-1290/HIF3A/HIF-1α axis, and miR-1290 may be a potential target in the prevention of myocardial ischemia-reperfusion injury. © 2017 IUBMB Life, 69(9):660-667, 2017.