Effects Of Different Patterns Swimming On Mitochondrial DNA Of Skeletal Muscle In Aged Mice In Duced By D-galactose

The severity of Chinese population aging is becoming significant in the 21st century. Facing with the problem caused by the increasing number of older people, it's our first priority to consider the problem of benefit to the aged and delaying the process of aging.The essay is to analyze the impact of exercise on the lack of mitochondrial DNA(mtDNA) of skeletal muscle of aged mice induced by D-galactose(D-gal), affiliated with demonstration of index of oxygen free radical metabolism, based on D-gal induced aging Kunming species mouse model as the subject.Subject: The study is researching the impact of exercise on the lack of skeletal muscle ntDNA and metabolism of oxygen free radical by interfering the exercise of D-gal aging mice based on the aging theory of free radical and damage to mtDNA. The thesis is also approaching the mechanism of exercise on delaying aging, providing evidence for delaying aging, improving life quality of older people by scientific exercise intervention.Method: To divide mice with age of eight months into 5 groups. Control group was injected with 100mg/kg/d NS (CS,n=5) and D-gal (CD n=4). No exercises for CS and CD,experimentation group using three different swimming ways〔load-free swimming(WN,n=8),load swimming (WR,n=8),combinative swimming (WS,n=7)〕After training 6 weeks detect SOD activity, MDA content and loss ratio of the mtDNA in the mice's gastrocnemius. exercises and the D-galactose injection are simultaneous. Rear loading, load weight is account for 5% of the total body weight. Compare the difference between CD and CS, WN, WR, WS, the differences among the groups WN, WR and WS.Result: Compared with CS group, CD there is remarkable increase on the MDA content in gastrocnemius tissue of the mice(P<0.01), SOD activity is significantly decrease (P <0.01), mtDNA loss ratio is significantly increase (P <0.01 ).Among D-galactose injection group, compared with CD group, MDA content significantly decrease in WN, WR, WS (P <0.05), SOD activity significantly increase (P <0.05), mtDNA loss ratio decrease significantly (P <0.05).There are not significantly different among the indexes of WN, WR and WS (P> 0.05).Conclusion: D-gal-induced aging mice model is one of the best models for anti-aging research, by detecting SOD activity and the content of MDA of gastrocnemius to determine the model of success. The lab result of SOD activity, MDA content and the loss ratio of mtDNA in the gastrocnemius show that D-gal aging mice get oxidative damage of aging on skeletal muscle, the degree of free radicals attack skeletal muscle increase, while the capability of eliminating oxygen free radical decrease, and exist phenomenon of universal mtDNA loss; through various forms of athletics intervention, it shows that the exercises can reduce loss ratio of mitochondrial and mitigate free radical damage, causes the antioxidase and mitochondria produce adaptive changes, thereby delaying aging or reduce the aging degree.