6周负重跑训练和补充大豆多肽对D-半乳糖衰老大鼠骨骼肌IGF-I mRNA和GDF-8 mRNA表达的影响

目的:探讨6周负重跑训练和补充大豆多肽对衰老大鼠骨骼肌IGF-I mRNA和GDF-8 mRNA表达的影响。方法:56只雄性SD大鼠随机分为7组:成年组,模型组,大负重组,小负重组,补肽组,补肽+大负重组和补肽+小负重组。除成年组外,其余各组大鼠采用6周D-半乳糖皮下注射复制亚急性骨骼肌衰老模型,同时按分组分别施加大(70%最大负重)、小(30%最大负重)两种负重方式的跑台训练或/和补充15%大豆多肽的干预。6周实验结束后禁食12小时,处死所有大鼠,无菌取材,测试骨骼肌IGF-I mRNA和GDF-8mRNA表达量。结果:与成年组相比,模型组骨骼肌IGF-I mRNA表达显著下降(P<0.01),GDF-8 mRNA表达显著升高(P<0.01),负重或补肽单独干预及其联合干预均可有效逆转以上趋势(P<0.01),并且负重和补肽两者具有显著交互作用。结论:负重跑训练或补充大豆多肽干预,可有效改善衰老大鼠骨骼肌IGF-I mRNA低表达和GDF-8 mRNA高表达,并且两种手段联合运用也可达到相同效果。

The Effect of 6 Week Weight Run Training and Soy Polypeptide Supplement on the Expression of IGF-I mRNA and GDF-8 mRNA in D-galactose Aging Rat Skeletal Muscle

Objective To investigate the effect of 6 week weight run training and soy polypeptide supplement on the expression of IGF-I mRNA and GDF-8 mRNA in D-galactose aging rat skeletal muscle.Methods 56 male SD rats were randomly divided into 7 groups:adult group,model group,light load exercise group,heavy load exercise group,peptide group,peptide and light load exercise group,peptide and heavy load exercise group.All the rats were modeled to subacute skeletal muscle aging model by 6-week D-galactose injection except adult group.Different interventions were adopted in different groups.After 12 hours fasting at the end of 6 week’s experiment,all rats were killed and tested the indicators of IGF-I mRNA and GDF-8 mRNA expression in skeletal muscle.Results Compare with adult group,skeletal muscle IGF-I mRNA expression in all model groups were significantly decreased(P<0.01),GDF-8 mR-NA expression were significantly increased(P <0.01).The intervention of weight run training or/and soy polypeptide supplement could reverse the above trends(P<0.01),there was a significant interaction between the weight run training and soy polypeptide supplement.Conclusion Weight run training or soy polypeptide supplement could improve the low expression of IGF-I mRNA and the high expression of GDF-8 mRNA in aging rats skeletal muscle effectively,and the combination could also reach the same effect.