电针对去神经支配骨骼肌萎缩大鼠PI3K/Akt/mTOR信号通路的影响

关键词：电针  肌萎缩  PI3K/Akt/mTOR信号通路

Keywords:electric acupuncture  muscle atrophy  PI3K/Akt/mTOR signaliing pathway

摘要：

      摘要 目的：研究电针对去神经支配骨骼肌萎缩大鼠PI3K/Akt/mTOR信号通路的影响，探讨电针延缓去神经支配骨骼肌萎缩的治疗机制。 方法：SD雄性大鼠63只随机分为假手术组(n=21)、模型组(n=21)和电针组(n=21)。模型组、电针组通过暴露并切断坐骨神经的方法制作去神经支配腓肠肌动物模型，假手术组暴露坐骨神经但不切断。术后1d，电针组术侧进行电针治疗，其余两组不做任何处理。分别在术后7d、14d和21d取材，测定术侧腓肠肌湿重比，Masson染色测定腓肠肌纤维直径、截面积，Western Blot检测PI3K、Akt以及mTOR蛋白表达、Akt以及mTOR蛋白磷酸化，PCR检测PI3K、Akt和mTOR基因表达。 结果：模型组与电针组大鼠腓肠肌的湿重比、肌纤维截直径以及面积均显著低于假手术组（P<0.001），且模型组与电针组比较，差异具有显著性（P<0.05）；电针组的PI3K、p-Akt、p-mTOR蛋白表达量均高于模型组与假手术组（P<0.05）；电针组的PI3K、Akt、mTOR mRNA表达也明显高于其余两组（P<0.05）。 结论：电针可延缓去神经性骨骼肌萎缩，其作用机制可能与电针激活PI3K/Akt/mTOR信号通路有关。

Abstract:

      Abstract Objective: To investigate the effects of electroacupuncture on PI3K/Akt/mTOR singaling pathway in denervated skeletal muscle atrophy in rats, and the mechanism of retarding the denervated skeletal muscle atrophy. Method:Totally 63 male SD rats were randomized to 3 groups(n=21 in each): control group, model group, EA group. model group and EA group were exposed and transected the rat sciatic nerve to build the model of denervated skeletal muscle atrophy.control group was exposed sciatic nerve only and not transected. Electroacupuncture was given to rats in EA group on the operation side 1d after modeling. While no any treatment were given to the other two groups. 3 groups were divided randomly into three subgroups on 7, 14, 21 days post operation. The muscle wet weight ratio of the operational side gastrocnemius were measured. Fiber diameter and cross-sectional area of the operational side gastrocnemius were determined by Masson staining. PI3K, Akt and mTOR protein expression and gene expression were detected by Western Blot and RT-PCR. The phosphorylation level of Akt and mTOR were observed by Western Blot. Result: The wet weight ratio, fiber diameter and cross-sectional area were significantly lower in model group and EA group than those in control group(P<0.001), and the wet weight ratio, fiber diameter and cross-sectional area were observably higher in EA group than those in model group (P<0.05). Comparing to model group and control group, the protein expression of PI3K, p-Akt and p-mTOR in EA group were higher markedly(P<0.05). And the gene expression of PI3K, Akt and mTOR were more higher in EA group than the other two groups (P<0.05). Conclusion: Electroacupuncture could retard the process of denervated skeletal muscle atrophy。 Its mechanism may be related to the activation of PI3K/Akt/mTOR signaling pathways.