眼针对脑缺血再灌注损伤大鼠脑组织自噬的影响

目的:观察眼针疗法对脑缺血再灌注损伤大鼠脑血流以及脑组织自噬的影响,探讨眼针对脑缺血再灌注损伤大鼠脑组织产生保护作用的机制。方法:将50只SD大鼠随机分为假手术组、模型组、眼针组、抑制剂组和增强剂组,每组10只。采用改良线栓法制备脑缺血再灌注损伤大鼠模型。眼针组大鼠在造模成功后0.5 h、12 h及24 h给予眼针干预30 min;抑制剂组和增强剂组大鼠在造模前30 min给予侧脑室注射自噬抑制剂3-甲基腺嘌呤和自噬诱导剂雷帕霉素,且抑制剂组和增强剂组给予同眼针组相同的眼针干预。在大鼠脑缺血再灌注后24 h用Longa评分法进行神经功能评分,用激光多普勒血流仪测量大鼠大脑皮层血流量和血流速度,用尼氏染色法观察缺血区脑组织神经元损伤情况,用Western blot法测定缺血区脑组织自噬相关蛋白Beclin-1、微管相关蛋白1轻链3(LC3)、p62的表达。结果:与假手术组比较,模型组大鼠神经功能缺损评分明显升高(P<0.01);大脑皮层血流量和血流速度明显降低(P<0.01);缺血区脑组织尼氏小体数量减少(P<0.01);Beclin-1蛋白表达水平和LC3-Ⅱ/LC3-Ⅰ升高,而p62表达水平降低(P<0.01)。与模型组比较,眼针组和抑制剂组大鼠神经功能缺损评分下降(P<0.01);大脑皮层血流量和血流速度均明显增加(P<0.01);缺血区脑组织尼氏小体的数量增多(P<0.01);Beclin-1蛋白表达水平、LC3-Ⅱ/LC3-Ⅰ明显降低,p62的表达水平明显升高(P<0.01)。增强剂组与模型组比较,上述各指标差异均无统计学意义(P>0.05)。结论:眼针能够改善脑缺血再灌注损伤大鼠的神经功能,其机制可能与增加脑血流量,加快脑血流速度以及抑制缺血区脑组织自噬有关。

Effect of eye acupuncture on autophagy in brain tissue of rats with cerebral ischemia-reperfusion injury

Objective to observe the effect of eye acupuncture on cerebral blood flow and autophagy of cerebral tissue in rats with cerebral ischemia-reperfusion injury, so as to explore the mechanism of eye acupuncture underlying improvement of cerebral ischemia-reperfusion injury. Methods Fifty SD rats were randomly divided into sham operation, model, eye acupuncture, inhibitor and enhancer groups,with 10 rats in each group. The rat model of cerebral ischemia-reperfusion injury was established by occlusion of the middle cerebral artery for 1.5 h. The rats in the eye acupuncture group were treated with eye acupuncture for 30 minutes immediately, 12 h and 24 h after the modeling. Rats in the inhibitor group and enhancer group were given intracerebroventricular injection of autophagy agonist 3-Methyladenine or autophagy inducer Rapamycin 30 min before modeling. Longa’s scoring method was used to evaluate the neurological function. The blood flow velocity of the cerebral cortex was mea-sured with a laser doppler blood flow meter, and the neuron damage in the brain tissue was observed with Nissl staining. The expressions of autophagy-related protein Beclin-1, microtubule-associated protein 1 light chain 3(LC3), and p62 were measured by Western blot. Results Compared with the sham operation group, the neurological score of the model group was significantly increased(P<0.01);the blood flow volume and blood flow speed were significantly reduced(P<0.01);the number of Nissl bodies in the ischemic brain tissue decreased(P<0.01);Beclin-1 protein expression level and LC3-II/LC3-I increased, while p62 expression level decreased(P<0.01). After intervention and in comparison with the model group, the neurological scores in the eye acupuncture group and inhibitor group decreased(P<0.01);blood flow volumn and blood flow speed significantly increased(P<0.01);the number of Nissl bodies increased(P<0.01);the expression level of Beclin-1 protein and LC3-II/LC3-I decreased, and the expression level of p62 increased(P<0.01). There was no significant difference between the enhancer and the model groups in the abovementioned indexes(P>0.05). Conclusion Eye acupuncture can improve the neurological function of rats with cerebral ischemia-reperfusion injury, which may be related to accelerating cerebral blood flow and inhibiting autophagy in the ischemic brain.