醒脑开窍针刺法对脑缺血再灌注损伤大鼠海马组织p-Akt(Ser473)表达及细胞凋亡的影响

Effect of the Xingnao Kaiqiao acupuncture therapy on expression of p-Akt (Ser473) and neurocyte apoptosis in the hippocampus of rats with cerebral ischemia/reperfusion injury

关键词:  醒脑开窍针刺法  脑缺血再灌注  细胞凋亡  PI3K/Akt信号通路

Key words:  Xingnao Kaiqiao acupuncture therapy  cerebral ischemia reperfusion  apoptosis  PI3K/Akt signaling pathway

摘要:

[目的]观察醒脑开窍针刺法对脑缺血再灌注损伤大鼠海马组织p-Akt（Ser473）表达及细胞凋亡的影响。[方法]将78只大鼠随机分为假手术组、模型组、电针组，每组26只。按Zea Longa线栓法复制大脑中动脉缺血再灌注模型（MCAO/R）。电针组给予针刺内关、人中、三阴交治疗，每日2次，持续治疗3 d。采用Zausinger 6分法评价神经功能，氯化三苯基四氮唑（TTC）染色检测脑梗死体积，苏木精-伊红（HE）染色观察海马组织病理损伤，流式细胞技术检测海马神经细胞凋亡率，Western Blot技术检测p-Akt（Ser473）、Bcl-2、Bax蛋白表达。[结果]电针组神经功能评分明显高于模型组（P<0.01），脑梗死体积明显小于模型组（P<0.01），海马组织病理损伤较模型组改善；电针组海马神经细胞总凋亡率明显小于模型组（P<0.05）；电针组p-Akt蛋白、Bcl-2蛋白表达、Bcl-2/Bax比值较模型组均明显增大（P<0.05，P<0.01），Bax蛋白表达较模型组明显减小（P<0.01）。[结论]醒脑开窍针刺法可明显改善局灶性脑缺血再灌注大鼠的神经功能，减轻神经细胞凋亡，其作用可能通过激活PI3K/Akt信号通路起到脑保护效应。

Abstract:

[Objective] To observe the effects of the Xingnao Kaiqiao acupuncture therapy on expressions of p-Akt (Ser473) and neurocyte apoptosis in the hippocampus of rats with cerebral ischemia/reperfusion injury.[Methods] The 78 Sprague-Dawley rats were randomly divided into three groups, the sham-operation group, the I/R group and the electroacupuncture group, 26 rats in each group. The cerebral ischemia reperfusion model was established by Longa's suture method. In electroacupuncture group, acupuncture was performed with Xingnao Kaiqiao method at main acupoints of Neiguan (PC6), Renzhong (DU26), Sanyinjiao (SP6) and the electric acupuncture apparatus was connected to ipsilateral Neiguan (PC6) and Sanyinjiao (SP6). Then acupunctures were followed twice daily for 3 days. Neurological deficits were assessed by ethologic scoring according to Zausinger's neurologic assessment scales, the 2, 3, 4-triphenyltetrazolium chloride (TTC) staining was used to detect infarct volume, pathological brain damage was estimated by performing hematoxylin and eosin staining. In addition, neurocyte apoptosis in the hippocampus was detected by flow cytometry and the protein expressions of p-Akt (Ser473), Bcl-2 and Bax in hippocampus were measured by Western blot.[Results] In comparison with the model group, the neurological deficits scores of the electroacupuncture group increased and the infarction volume decreased obviously (P<0.01), the pathological damage alleviated significantly. At the same time, compared with model group, the hippocampal neuron's total apoptosis rate obviously decreased (P<0.05)in electroacupuncture group accompanied with the increments of protein expressions of p-Akt (Ser473), Bcl-2 and the ratio of Bcl-2/Bax (P<0.05, P<0.01), and with the reduction of protein expression of Bax (P<0.01).[Conclusion] Xingnao Kaiqiao acupuncture therapy can significantly improve neurological function and reduce neurocyte apoptosis in rats with focal cerebral ischemia reperfusion injury. The protective effects of acupuncture on the brain may be achieved by activating the PI3K/Akt signaling pathway.