夹脊电针调节自噬流促进大鼠脊髓损伤修复

Jiaji EA Regulating Autophagic Flow and Promoting Repair of SCI in Rats

目的:探讨夹脊电针对脊髓损伤大鼠自噬流的影响,明确其促进脊髓损伤修复的机制。方法:实验采用NYU Impactor M-Ⅲ打击器制作Allen’s模型,将48只大鼠随机分为4组,分别为假手术组(Sham)、模型组(Model)、夹脊电针组(EA)和夹脊电针+抑制剂组(EA+CQ)。每组各12只,再将每个实验组按照不同的治疗时间分为3 d组和7 d组两个亚组,每组各6只。治疗3 d和7 d后采用BBB评分对大鼠后肢运动功能进行观察,评分后麻醉处死取出受损节段脊髓组织进行免疫组化和WB检测,观察自噬体标记因子LC3、LC3-Ⅱ和自噬底物P62的表达情况。结果:Model组和Sham组比较,BBB评分降低,差异具有统计学意义(P<0.01),LC3、LC3-Ⅱ和P62的表达含量增加,差异具有统计学意义(P<0.01),EA组和Model组比较能促进大鼠后肢运动功能的恢复,差异具有统计学意义(P<0.05),增强LC3、LC3-Ⅱ的表达含量,差异具有统计学意义(P<0.05),降低P62的表达,差异具有统计学意义(P<0.05),说明夹脊电针可以促进自噬流。而在夹脊电针治疗的基础上注射抑制剂可增强LC3和LC3-Ⅱ的表达,差异具有统计学意义(P<0.05),并逆转BBB评分和P62的表达,差异具有统计学意义(P<0.01)。结论:脊髓损伤后自噬流堵塞,而夹脊电针治疗能促进自噬流修复损伤脊髓,改善大鼠后肢运动功能。

Objective: To investigate the effect of Jiaji electro-acupuncture(EA) on autophagic flow in rats with spinal cord injury(SCI), and to clarify its mechanism in promoting SCI repair. Methods: The experiment used NYU Impactor M-Ⅲ to make Allen’s model. 48 rats were randomly divided into the sham operation group, the model group, the Jiaji EA group and the Jiaji EA plus inhibitor group, with 12 rats in each group. Each group was sub-divided into two subgroups, that is 3 d group and 7 d group according to different treatment time. BBB score was used to observe the motor function of hind limbs. The damaged spinal cord tissue was collected for immunohistochemistry and WB detection. The expressions of autophagosome labeling factor LC3, LC3-Ⅱ and autophagy substrate P62 were detected in the groups. Results: Compared with those in the sham operation group, the BBB score was decreased(P<0.01), and the expressions of LC3, LC3-Ⅱ and P62 were increased(P<0.01). Compared with those in the model group, the recovery of motor function of hind limbs was promoted(P<0.05), the expression of LC3, LC3-Ⅱ was increased(P<0.05), and the expression of P62 was reduced(P<0.05), indicating that Jiaji EA could promote autophagic flow. On the basis of Jiaji EA treatment, the injection of inhibitors enhanced the expressions of LC3 and LC3-Ⅱ(P<0.05), whereas reversed the BBB score and the expression of P62(P<0.01). Conclusion: Autophagy flow is blocked after SCI, and Jiaji EA can promote the autophagy flow to repair the injured spinal cord and improve the motor function of hind limbs in the rats.