Effect Of Weight Training On Aging Rats' Sarcopenia

With the increasing of aging population in the world, the problems concerning with aged society become an obvious contravention in many countries. The governments focus on people's healthy life-span and life quality. Meanwhile, the senescence is also a new field for scientists. Recent years, the scientists pay more attention to the issue of decline of muscle function, because it can influence old people's health. It is close correlative between the muscle function and senescence.Sarcopenia is the degenerative loss of skeletal muscle mass and strength in senescence, it is regarded as the main reason of the degenerative changing on elder people's muscle function. Therefore, more and more scientists became interested in the new field. Researches proved that the sarcopenia can be affected by weight training, and some regulations of sarcopenia were also discovered. But it is still absent of the experimental research on mechanism of sarcopeina and its changing under weight training. The purpose of this study is to explore the pathological and histological character of senescence muscle, also to discover the effect and mechanism of weight training on sarcopenia.The main work of this study focused on: (a) Discovering the histological changing of aging mouse muscle, and if the histology methods are available for sarcopenia research. (b) Seeking an effective workload of weight training for old mouse. (c) Exploring the effect and mechanism of weighting training on old mouse's sarcopeina.The methods and process of this study can be summerized as three experiments.Experiment one: Reseach on the sports ability of Sprague & Dawley mouseThe SD mouses were the subjects of this study and a few past studies were concerning this problem, so, it is necessary to make sure that the mouse runing and weight load capacity, as well as their anaerobic threshold, so as to contol the coming experiment. Meanwhile, the young and old mouses' sports ability were compared in this experiment.Experiment two: The histological character of old mouse's muscleThe 4 months age mouse and 16 months age mouse were compared on their muscle micro-structure by using histological methods, include H&E, NADH, Gomori and ATPase dyeing ways. The abnormal histological images were picked up and analyzed.Experimental three: Effect and mechanism of weight training on aging mouses' sarcopenia.8 4-month aged mouses were regarded as young contrast group. 32 16-month aged mouses were assigned into three groups randomly, 8 mouses in each group. They separately engaged in light weight load, heavy weight load running exercise and none load running exercise. All the subjects experienced 6 weeks training. The testing index include SOD, MDA, LP. The histological images were also analyzed like experiment two. Meanwhile, the Western Blot experiment was conducted for testing muscle MG29.The results of three experiments as above showed that: [1] The 16-month-aged mouses had poorer ability than 4-month-aged mouses. Their anaerobic throshold curved at 30m/min running speed. [2] Some typical abnormal histological images were find in old mouses muscle. The obvious different existed between the young group and the old group. [3] The light load weight training was effective on improving muscle function. At the same time, the changing of muscle MG29 was sensitive for weight training.Conclusion:(1)Some abnormal histological images can be find in old mouses' muscle, it is proved that the histological methods is available for sarcopenia reseach.(2)30% maximum weight training is effective for discreasing the abnormal histological imaging in mouses' muscle. So it is beneficial for restraining sarcopenia. While 60% maximum weight training probably injured mouses' muscel.(3) It is very different between mouse and human on compose of different muscle fiber types. The different fiber types have distinct reaction under different weight load. The type II fibers changed more active during the weight training.(4)MG29----an important membrane protein was very sensitive for weight training, and 30% maximum weight load was most effectvie for MG29 increasing. 60% maximum weight seemed to be adverse. The old mouses' MG29 were lower than young mouses' obviously.