Effects of Long-term Endurance Training on Autophagy-related Factors Beclin1 and LC3 of Rat Cardiomyocytes

Objective:Through experimental research of expression changes on autophagy-related factors Beclin1 and LC3,this paper explores the influence of long-term endurance training on the degree of rat cardiomyocyte autophagy,and in order to provides experimental evidence for the long-term endurance training inducing mechanism of autophagy.Methods:Select 24 SD rats were grouped to control group,moderate intensity group and high instensity group with 8animals in each group.Respectively does 16 weeks treadmill training on 15.2m/min speed of 5°slope and 28m/min speed of 10°slope,5days/weeks,1h/day.Make detection of echocardiography after 16 weeks training.Left ventricular wall used in HE staining,observe the myocardial tissue,preparation of ultrathin slices for transmission electron microscope,testing level of autophagy.Use RT-PCR,Western Blot to detect autophagy-related genes Beclin1 and LC3mRNA and protein expression of rat cardiomyocytes.Results:1)Echocardiography showed that,after 16 weeks treadmill training,high intensity group EF value is lower than control group(P<0.05);2)HE staining results showed that,high intensive group of myocardial cell injury is serious;3)TEM analysis suggests that long terms high intensity endurance training increased degree of autophagy;4)After 16 weeks training,RT-PCR results that the expression of autophagy-related genes Beclin1 and LC3 was raised;5)Western Blot suggests that,compair with control group,both moderate intensity group and high instensity group,the expression of Beclin1 and LC3-II/LC3-I ratio was significantly increased(P<0.05),and high intensity training group was significantly higher than moderate intensity training group(P<0.05).Conclusion:1)Mderate intensity endurance exercise can cause cardiac tissue good adaptability remodeling,promote appropriate levels of autophagy and activity of myocardial cells,which effectively increases the expression of Beclin1 and LC3 and improve LC3-II/LC3-I ratio,increase cardiac cells metabolism,and in favor of myocardial energy metabolism and contractile function;2)High intensity endurance exercise can cause myocardial fiber damaged,autophagy abnormal increased,Beclin1 and LC3over-expressed,and form the structure and basis of the molecular pathology of myocardial cell injury.