Lei Bing-Kai, Zhao Shuo, Xu Tao, Zhou Yue, Xu Shou-Sheng, Wang Rui-Yuan, Li Jun-Ping
School of Sports Human Science, Beijing Sport University, Beijing 100084, China.
Zhen Ci Yan Jiu. 2021 Apr 25;46(4):306-11. doi: 10.13702/j.1000-0607.200471.
To observe the changes of the skeletal muscle fibrosis and changes of transforming growth factor-β1(TGF-β1)/ extracellular signal-regulated kinase (ERK) / connective tissue growth factor (CTGF)pathway in rats after long-term eccentric exercise and acupuncture intervention, so as to explore the mechanism of acupuncture in regulating exercise-induced skeletal muscle fibrosis.
A total of 30 male SD rats were randomly divided into normal control, exercise and acupuncture group, with 10 rats in each group. The rat model of skeletal muscle fibrosis was established by eccentric exercise for 3 weeks. After exercise trained every time, the rats of the acupuncture group received acupuncture stimulation by holding the acupuncture needle to obliquely and longitudinally penetrate the ventral part of triceps of the lower leg along its lateral side, followed by retaining the needle for 2 min. Changes of the collagen fibers in each group was observed by scanning electron microscope. The expressions of Collagen Ⅰ, TGF-β1, phosphated (p)-ERK/ERK and CTGF proteins were detected by Western blot.
After 3 weeks of eccentric exercise and acupuncture, the fibrosis and deposition of collagen fibers in the exercise group were significantly higher than that in the normal control group,the degree of fibrosis in the acupuncture group was significantly lower than that in the exercise group. Compared with the normal control group, the expression levels of Collagen Ⅰ, TGF-β1, CTGF and p-ERK/ERK in the exercise group was significantly higher (<0.01，<0.05). After EA interventions, the increased levels of the above indicators were significantly reversed (<0.05，<0.01) apart from p-ERK/ERK which had a downward trend, but the difference was not statistically significant.
The accumulation of chronic sports injury can lead to the deposition of collagen fibers in skeletal muscle, which leads to the fibrosis of skeletal muscle. Acupuncture can inhibit skeletal muscle fibrosis via down-regulating TGF-β1/ERK/CTGF signaling pathway.
观察长期离心运动及针刺干预后大鼠骨骼肌纤维化变化及转化生长因子-β1（TGF-β1）/细胞外信号调节激酶（ERK）/结缔组织生长因子（CTGF）通路的变化，以探讨针刺调节运动性骨骼肌纤维化的机制。
将30只雄性SD大鼠随机分为正常对照组、运动组和针刺组，每组10只。采用离心运动3周建立大鼠骨骼肌纤维化模型。每次运动训练后，针刺组大鼠沿小腿三头肌外侧腹面斜向、纵向进针，提插捻转得气后留针2分钟。通过扫描电子显微镜观察各组胶原纤维变化。采用蛋白质免疫印迹法检测Ⅰ型胶原、TGF-β1、磷酸化（p）-ERK/ERK及CTGF蛋白表达。
离心运动3周并针刺干预后，运动组胶原纤维纤维化及沉积程度显著高于正常对照组，针刺组纤维化程度显著低于运动组。与正常对照组比较，运动组Ⅰ型胶原、TGF-β1、CTGF及p-ERK/ERK表达水平显著升高（<0.01，<0.05）。针刺干预后，除p-ERK/ERK呈下降趋势但差异无统计学意义外，上述指标升高水平均显著逆转（<0.05，<0.01）。
慢性运动损伤积累可导致骨骼肌胶原纤维沉积，引起骨骼肌纤维化。针刺可通过下调TGF-β1/ERK/CTGF信号通路抑制骨骼肌纤维化。
