Effect Of Ladder-climbing Training On 8-OH-dG, P53 And Bax Gene Expression In Skeletal Muscle Of SAMP8

Sarcopenia is a general syndrome that is characterized by a progressive loss of strength and muscle mass, and it will have serious impact on the daily lives of elderly people, public health , health care cost. On the mechanism of Sarcopenia, it is the focus of taking certain precautionary measures to prevent Sarcopenia, but its mechanism is not clear. It is only to study from the different mechanism of its occurrence. Among them, skeletal muscle fibers are susceptibility to apoptosis in the aging process. It may be irreversible damage to the quality and strength of skeletal muscle, resulting in a decline in skeletal muscle function, affecting the movement of older persons capacity, resulting in the elderly of the obstacles in their daily lives.Mitochondria-mediated apoptosis signaling pathway plays a pivotal role in the process of apoptosis, is the center of apoptosis, whereas mitochondrial-mediated apoptosis signaling pathway directly affects the process of adjusting to the process of cell apoptosis. In the process of aging, the level of oxidative stress increasing to the accumulation of DNA damage process may lead to an increase in p53 gene expression, which directly affect the Bcl-2/Bax, and it is key factors to regulate the mitochondria-mediated apoptosis signaling pathway. Regular exercise (mainly in resistance training) can be reduced oxidative stress to damage DNA with age-related, exercise also play a role in regulation stress gene expression. Therefore, exercise has a certain role in the mitigation and prevention to age-related DNA damage, regulation the susceptibility to apoptosis, becoming one of the important means to prevent Sarcopenia occurred.The article through training young and elderly male SAMP8 mice to climb ladder, observation of effect of aged and climb ladder training on DNA damage, p53 and Bax mRNA expression level , affecting wither susceptibility to apoptosis with the aging process.Methods: 50 SAMP8 mice were 12 weeks of week-old, 16 weeks and 24 weeks of age, including 12 weeks of age 20, 16 weeks of age 10 and 24 weeks of age 20. 12-week-old SAMP8 mice were divided into two groups in random, young contrast group, young training group, 10 each group, young training group engaged in climbing training for 8 weeks, 3 times a week. 16-week-old training group engaged in climbing training for 21 weeks, 3 times a week. 24-week-old SAMP8 mice were divided into two groups in random, old contrast group, old training group, 10 each group, old training group engaged in climbing training for 8 weeks, 3 times a week. Through the ELISA kit for determination of DNA damage, real-time quantitative PCR instrument used to determine p53 and Bax mRNA expression.Results: 1) With age growing, skeletal muscle wet weight decreased significantly but there were no big changes in body weight, while climbing ladder has no significant impact on skeletal muscle wet weight.2) With age growing, DNA damage marker 8-OH-dG content in skeletal muscle fibers increased significantly, while ladder training inhibit 8-OH-dG content in skeletal muscle fibers. 3) With age growing, p53mRNA expression increased significantly, while the ladder training significantly inhibited the expression of skeletal muscle fibers p53mRNA in skeletal muscle fibers. 4) With age growing, Bax mRNA expression increased significantly, while the ladder training of skeletal muscle fibers inhibit the expression of Bax mRNA in skeletal muscle fibers.Conclusion:1 With age growing, the quality of the growth of skeletal muscle to reduce body weight but no significant changes in adipose tissue may be due to the substitution resulted in no change in body weight.2 With age growing, oxidative stress levels changed resulting in increasing DNA damage skeletal muscle fibers. Ladder training inhibited the DNA damage, an increase of the stability of genomic DNA.3 With age growing, DNA damage increased, leading to increasing expression p53mRNA, and ladder training inhibit DNA damage, p53mRNA expression decreased, reducing the age of skeletal muscle fiber apoptosis in the early molecular susceptibility.4 With age growing, Bax mRNA expression increased, regulation of mitochondrial-mediated apoptosis signaling pathway, an increase of muscle fiber of the probability of occurrence of apoptosis. Ladder training can significantly inhibit the expression of Bax mRNA and reduce the aging muscle fibers when the probability of occurrence of apoptosis.