Trimetazidine combined with exercise improves anti-stress capacity through enhancing autophagy and apoptosis of myocardium in mice. (25th November 2020) - Jiang, L
Abstract: Aims: To observe the effects of trimetazidine, aerobic exercise alone or combined on the anti-stress capacity of mice, and further explore its potential mechanism. Methods: Forty-four C57/BL male mice aged 8 weeks were randomly divided into four groups: control group (group C, n=11), exercise group (group E, n=11), trimetazidine (TMZ)group (group T, n=11), exercise combined with TMZ group (group TE, n=11). Saline intragastric administration, medium intensity swimming training, TMZ (10mg/kg) intragastric administration, medium intensity swimming training combined with TMZ intragastric administration were given respectively. Swimming for 6 days a week, 1 hour a day lasting for 4 weeks. After the intervention, each group was randomly subdivided into the rest and the exhaustive exercise (EE) subgroups. The mice in the EE-subgroup (n=6) underwent exhaustive exercise. The myocardial ultrastructure was observed under electron microscope to measure the anti-stress ability of mice. The expression of key autophagy proteins LC3-II, P62 and BNIP3 were detected and the number of myocardial autophagosomes were observed under electron microscope. The protein of apoptosis related, Bcl-2 and the expression of heat shock protein 70 (HSP70) were also being detected. Results: Exhaustive exercise induced the cardiac muscle damage successfully. TMZ and exercise alone or combined alleviated the cardiac damage significantly with improved autophagy (P<0.05) at the basal state and after exhaustive exercise. The level of apoptosis (P<0.05) and the expression of HSP70 was upregulated after the exhaustive exercise. Conclusions: TMZ and exercise alone improved the anti-stress capacity of mice effectively and the combination has a synergistic effect. The mechanism may be related to the promotion of autophagy, apoptosis and HSP70 expression of myocardium. Funding Acknowledgement: Type of funding source: Public grant(s) – National budget only. Main funding source(s): China natual science founding