CDC-like kinase 3 deficiency aggravates hypoxia-induced cardiomyocyte apoptosis through AKT signaling pathway

Hypoxia-induced cardiomyocyte apoptosis is one major pathological change of acute myocardial infarction (AMI), but the underlying mechanism remains unexplored. CDC-like kinase 3 (CLK3) plays crucial roles in cell proliferation, migration and invasion, and nucleotide metabolism, however, the role of CLK3 in AMI, especially hypoxia-induced apoptosis, is largely unknown. The expression of CLK3 was elevated in mouse myocardial infarction (MI) models and neonatal rat ventricular myocytes (NRVMs) under hypoxia. Furthermore, CLK3 knockdown significantly promoted apoptosis and inhibited NRVM survival, while CLK3 overexpression promoted NRVM survival and inhibited apoptosis under hypoxic conditions. Mechanistically, CLK3 regulated the phosphorylation status of AKT, a key player in the regulation of apoptosis. Furthermore, overexpression of AKT rescued hypoxia-induced apoptosis in NRVMs caused by CLK3 deficiency. Taken together, CLK3 deficiency promotes hypoxia-induced cardiomyocyte apoptosis through AKT signaling pathway.