Simulated microgravity-induced apoptosis of myocardiocytes and its mechanism

Objective To study the effect of simulated microgravity on apoptosis of in vitro cultured rat myocardiocytes and its mechanism. Methods Primarily cultured new born rat myocardiocytes was used as an experimental material and microgravity effect was simulated with clinostat. Myocardiocyte apoptosis–related molecule c-myc mRNA was detected by RT-PCR after simulated microgravity. Effect of 96 h simulated microgravity on expressions of transcriptional factors c-myc, GATA-4 and MEF2A proteins was detected by western blot. Results The expression level of myocardiocyte apoptosis–related molecule c-myc mRNA and protein was significantly higher whereas the expression level of transcriptional factors GATA-4 and MEF2A was significantly lower in experimental group than in control group after simulated microgravity (P< 0.05). Conclusion Clinostat-simulated microgravity upregulates the apoptosis of cardiomyocytes by down-regulating the expression of transcriptional factors GATA-4 and MEF2A.