[电针对大鼠失神经骨骼肌萎缩及IGF-1/PI3K/AKT表达的影响]

[Effect of electroacupuncture on denervated skeletal muscle atrophy and expression of IGF-1/PI3K/AKT in rats].

作者信息

Chen Xuan, Ye Xiaoran, Huang Xiaoqing

机构信息

Fujian Research Institution of TCM, Fuzhou 350003, China.

出版信息

Zhongguo Zhen Jiu. 2018 Dec 12;38(12):1311-7. doi: 10.13703/j.0255-2930.2018.12.015.

DOI:10.13703/j.0255-2930.2018.12.015

PMID:30672220

Abstract

OBJECTIVE

To observe the effects of electroacupuncture (EA) on denervated skeletal muscle atrophy and expression of IGF-1/PI3K/AKT signaling pathway in rats, and to explore the possible mechanisms of it.

METHODS

Thirty-six male SD rats were randomly divided into a control group, a model group and an EA group. Denervated muscle atrophy model was made by cutting off the left hindlimb sciatic nerve in the model group and the EA group. In the EA group, EA, dense-disperse wave, 2 Hz/33 Hz and 1.5-2 mA, was connected at "Zusanli" (ST 36) and "Shangjuxu" (ST 37). The treatment was given for 30 min every time, once a day and a total of 20 times were needed, there was 2 days interval every 5 times. The rats in the control group and model group were fixed in the same cage every day but not applied EA. Sciatic nerve function index (SFI) and ratio of muscle wet weight (RWW) were measured after treatment. HE staining was used to determine the ratio of cross-sectional area (RCA) and the ratio of fiber diameter (RFD). TUNEL and double immunofluorescence staining were used to evaluate the myocyte apoptosis, proliferation and differentiation. The mRNA expressions of IGF-1 and AKT were detected by real-time PCR. The total protein of AKT, p-AKT (Ser473) and p-AKT (Thr308) were detected by western blot.

RESULTS

Compared with the control group, SFI, RWW, RCA and RFD of the model group were significantly decreased and apoptotic index of myocytes were significantly increased (all <0.01). Compared with the model group, the above indexes of the EA group were improved (all <0.05), and the expressions of PAX3 and PAX7 related to proliferation and differentiation of muscle satellite cells were significantly increased (both <0.01), p-AKT (Ser473) protein level was increased (<0.05).

CONCLUSION

EA can improve the atrophy of denervated muscles, reduce myocyte apoptosis, and promote the proliferation and differentiation of muscle satellite cells. The mechanism may be related to the increase of p-AKT (Ser473) level and activation of AKT signaling pathway.

摘要

目的

观察电针（EA）对大鼠失神经支配骨骼肌萎缩及胰岛素样生长因子-1（IGF-1）/磷脂酰肌醇-3激酶（PI3K）/蛋白激酶B（AKT）信号通路表达的影响，并探讨其可能机制。

方法

将36只雄性SD大鼠随机分为对照组、模型组和电针组。模型组和电针组通过切断左后肢坐骨神经制备失神经支配肌肉萎缩模型。电针组在“足三里”（ST 36）和“上巨虚”（ST 37）连接电针，疏密波，2 Hz/33 Hz，1.5 - 2 mA。每次治疗30分钟，每天1次，共需治疗20次，每5次间隔2天。对照组和模型组大鼠每天固定于同一笼中但不施加电针。治疗后测量坐骨神经功能指数（SFI）和肌肉湿重比（RWW）。采用苏木精-伊红（HE）染色测定横截面积比（RCA）和纤维直径比（RFD）。采用末端脱氧核苷酸转移酶介导的缺口末端标记（TUNEL）和双重免疫荧光染色评估肌细胞凋亡、增殖和分化。通过实时荧光定量聚合酶链反应（real-time PCR）检测IGF-1和AKT的mRNA表达。采用蛋白质免疫印迹法（western blot）检测AKT、磷酸化AKT（Ser473）和磷酸化AKT（Thr308）的总蛋白。

结果

与对照组相比，模型组的SFI、RWW、RCA和RFD显著降低，肌细胞凋亡指数显著升高（均P<0.01）。与模型组相比，电针组上述指标得到改善（均P<0.05），与肌肉卫星细胞增殖和分化相关的配对盒蛋白3（PAX3）和配对盒蛋白7（PAX7）表达显著增加（均P<0.01），磷酸化AKT（Ser473）蛋白水平升高（P<0.05）。