ABHD15 promotes cell viability, glycolysis, and inhibits apoptosis in cardiomyocytes under hypoxia

Abstract Background and aims Myocardial infarction (MI) has been an important heart disease affecting human health. The aim of this study was to investigate the regulatory effect of abhydrolase domain containing 15 (ABHD15) on hypoxic cardiomyocytes. Methods and results Hypoxic cardiomyocytes are commonly used as an vitro model for the study of MI. We found that cardiomyocyte viability was decreased under hypoxia, but cell glucose uptake, insulin receptor phosphorylation level and apoptosis were increased. Interestingly, ABHD15 expression was up-regulated in hypoxia-induced cardiomyocytes. Then, we identified the function of ABHD15 in hypoxic cardiomyocytes by using ABHD15 overexpression vector or short interfering RNA (siRNA) against ABHD15. The results showed that overexpression of ABHD15 promoted hypoxic cardiomyocyte viability, glucose uptake and IR phosphorylation (p-IR), and inhibited cell apoptosis. However, knockdown of ABHD15 attenuated hypoxic cardiomyocyte viability, glucose uptake and IR phosphorylation, and promoted apoptosis. Moreover, we found that ABHD15 promoted glucose transporter 4 (GLUT4) expression, translocation and enhance rate-limiting enzyme activation of glycolysis, thereby affecting glucose uptake. Furthermore, our study suggested that ABHD15 may affect the viability and apoptosis of hypoxic cardiomyocytes through IR/Ras/Raf/ERK/MEK and IR/PI3K/AKT/Bcl2/Bad/caspase9 signaling pathways, respectively. When the phosphorylation of IR, Raf or ERK was blocked by inhibitors, the protective effect of overexpressing ABHD15 on the viability of hypoxic cardiomyocytes was eliminated. Furthermore, inhibiting the phosphorylation of IR, AKT or Bcl2 abolished the inhibitory effect of overexpressing ABHD15 on hypoxic cardiomyocyte apoptosis. Conclusion ABHD15 regulated myocardial cell viability, glycolysis, and apoptosis under hypoxia, providing a novel potential therapeutic strategy for MI.