负荷渐增式训练对老年小鼠骨骼肌卫星细胞AMPK磷酸化的影响

目的 探讨负荷渐增式训练对老年小鼠骨骼肌卫星细胞腺苷酸活化蛋白激酶（AMP-activated protein kinase，AMPK）磷酸化的影响。方法 实验小鼠分为 3 组：青年对照组（YC组，n=12）、老年对照组（OC组，n=12）与老年运动组（OT组，n=12）。OT组进行负荷渐增式训练，流式细胞分选技术分离CD45-/CD31-/Sca1-/VCAM(CD106)+细胞群体，分选细胞通过desmin、Myod肌原性染色以及成肌分化诱导培养进行肌卫星细胞鉴定，免疫组化结合Western blotting方法检测肌卫星细胞p-AMPK水平。结果 YC组骨骼肌卫星细胞AMPK及p-AMPK表达水平显著高于OC组（P<0.05）；OT组与OC组AMPK表达无明显变化（Ｐ>0.05），而OT组p-AMPK表达水平显著高于OC组（P<0.05）。结论 负荷渐增式训练可促进老年小鼠骨骼肌卫星细胞AMPK磷酸化，改善老年小鼠骨骼肌能量代谢。

Effects of Incremental Load Training on Phosphorylation of AMPK in Skeletal Muscle Satellite Cells of Aged Mice

Objective To investigate the effect of incremental load training on AMP-activated protein kinase (AMPK) phosphorylation in skeletal muscle satellite cells of aged mice. Methods Experimental mice were divided into 3 groups: young control group (YC group, n=12), old control group (OC group, n=12) and old training group (OT group, n=12). The mice in OT group received incremental load training, and CD45-/CD31-/Sca1-/VCAM (CD106) + cells were isolated by flow cytometry sorting. Desmin, Myod myogenic staining and myogenic differentiation culture were used for identification of muscle satellite cells, and the p-AMPK level of muscle satellite cells was detected by immunohistochemistry combined with Western blotting method. Results The expression levels of AMPK and p-AMPK in skeletal muscle satellite cells in YC group were significantly higher than those in OC group (P<0.05). AMPK expression in OT group and OC group did not change significantly (P>0.05), while p-AMPK expression level in OT group was significant higher than that in OC group (P<0.05). Conclusions Incremental load training can promote AMPK phosphorylation of skeletal muscle satellite cells in aged mice, and improve energy metabolism of skeletal muscle in aged mice.