Effects of Rapamycin and LY294002 on the Skeletal Muscle of Rat with Swimming Training
|School||Shanghai Institute of Physical Education|
|Course||Human Movement Science|
|Keywords||skeletal muscle rat LY294002 rapamycin exercise|
Purpose: Skeletal muscle is an important organ of the body, which is ralated to the exercise abilit and overall metabolic.Exercise can promote skeletal muscle growth and hypertyophy,the study found that PI3K/Akt/mTORsignaling pathway is important to muscle protein synthesis. LY294002 (PI3K inhibitor) and Rapamycin (mTOR inhibitor) play an critical role in the study of the pathway,and widely used in clinical practice.However,the mechanisms that regulate muscle hypertrothy induced by the exercise is poorly understood.The purpers of this study is to establish the exercise-induced muscle hypertyophy model,explore LY294002 and Rapamycin role in the PI3K/Akt/mTOR signaling pathway,and to further enrich the molecular mechnism of skeletal muscle hypertropy in experimental evidence.Methods: 40 male adult Sprague-Dawley rats which load 15% by weight and intermittent swimming training.The subjects are grouped into control group(C),trainning group(T), trainning + LY2940002 group(TL), trainning + Rapamycin group(TR) and trainning + LY2940002 + Rapamycin group(TLR).The inhibitors were injection. The training adopted interval training protocol with load and training every other day with 8 weeks. The biopsy after 8 weeks was taken 24hs after the last trainning.Biopisies were taken from the gastrocnemius and soleus muscles.Using Western Blotting detecte the the protein expession of PI3K/Akt/mTOR and the phosphorylation in the skeletal muscle. Results: After 8 weeks treatment,the body weight of C group was significant higher than others,and no significant was observed in skeletal muscle mass between other groups, but the Soleus and Gastrocnemius Muscle Mass Index in training T group increased significantly compared with control group(p<0.05). Compared with the control group, the ratio of P-PI3K/PI3K、P-Akt/Akt、P-mTOR/mTOR in T group increased with insignificant difference, but the ratio in TR and TRL groups was significantly reduced(p<0.05).Conclusions: These results suggest that the interval training protocol is helpful to increase the relative muscle hypertrophy, and LY294002 and Rapamycin had a inhibition role in the PI3K/Akt/mTOR pathway responding to training.