Objective To determine whether taurine has protective effects on chicken myocardial apoptosis induced by hypoxic condition through inhibiting calpain-1 derived mitochondrial apoptotic pathway. Methods Chicken primary embryonic myocardial cells were isolated and cultured at 37 °C under a 5% CO2 atmosphere. Firstly the optimum concentration of taurine or PD150606 was chosen by detecting the cell viability. Chicken cardiomyocytes were cultured in 95% N2-5% CO2 atmosphere for 12 h to produce hypoxic conditions. Before hypoxic treatment, 10 mM taurine and 10 uM PD150606 (a specific calpains inhibitor) were added separately or together. The cell apoptosis was detected by acridine orange/ethidium bromide (AO/EB) double staining. Western blotting was used to determine the protein expressions of calpain-1, cytochrome c, Bcl-2, procaspase-9 and procaspase-3 in the cardiomyocytes. Results Taurine administration effectively attenuated the myocardial apoptosis under hypoxic condition, reduced the calpain-1 protein level. In addition, pre-treated taurine could up-regulate the protein expressions of Bcl-2 and procaspase-3 in hypoxic myocardial cells, down-regulate protein expression levels of cytochrome c and procaspase-9. Moreover, taurine exhibited same inhibition effect as PD150606 on the cell apoptosis and proteins express under hypoxic condition. Conclusions Taurine could attenuate the chicken cardiomyocyte apoptosis impaired by hypoxia through inhibiting calpian-1-derived mitochondrial apoptotic pathway in vitro.
Keywords: Apoptosis; Calpain-1; Chicken primary myocardial cells; Mitochondrial apoptotic pathway; Taurine.