电针对APP/PS1转基因小鼠海马及血脑屏障Aβ水平的影响

摘要

Objective:To observe the effect of electro-acupuncture on the level of Aβ1-42 in hippocampus and blood brain barrier (BBB), and behavior of APP/PS1 transgenic mice to explore whether electro-acupuncture can improve the ability of Aβ clearance to treat Alzheimer's disease (AD). Methods:24 APP/PS1 transgenic mice (6 months, male) were randomly divided into the electro-acupuncture group and the model group, another 12 C57BL/6 mice were used as the blank control. The electro-acupuncture group was treated with electro-needling GV20 and KI1. After the treatment, Morris water maze was used for behavioral testing to observe the learning and memory abilities in the mice; the expression level of Aβ1-42 in hippocampus was determined by ELISA; the expression of Aβ1-42 in the micro-vascular wall of hippocampus was observed by colloidal gold immuno-electron microscopy. Results:Morris water maze test showed that the escape latency of the model group increased; the times of site crossings, percentage of swimming time and swimming distance were lowered in the model group than those in the blank control group(P ＜0. 01, P ＜0. 05); whereas, the escape latency in the electro-acupuncture group was obviously decreased (P ＜0. 01). The ELISA result showed that the expression of Aβ1-42 in hippocampus was decreased significantly in the electro-acupuncture group compared to that in the model group (P ＜0. 01). The immuno-electron microscopy result showed that the colloidal gold particles in the hippocampal microvascular wall were decreased in the electro-acupuncture group compared to those in the model group. Conclusion:Electro-acupuncture can improve the spatial cognitive ability and reduce Aβ1-42 level of hippocampus in APP/PS1 transgenic mice, which mechanism may be related to the improvement of Aβ clearance ability of BBB.%目的:通过观察电针对APP/PS1转基因小鼠海马、血脑屏障Aβ及行为学的影响,探讨电针能否通过改善血脑屏障Aβ清除能力来治疗阿尔茨海默病.方法:将24只6月龄雄性APP/PS1转基因小鼠随机均分为电针治疗组与模型组,正常对照组选取12只同性别的C57BL/6野生背景鼠.电针治疗组电针"百会""涌泉"穴,治疗后采用Morris水迷宫进行行为学检测,观察各组小鼠学习记忆能力;用ELISA测定Aβ1-42在海马的表达水平;使用胶体金免疫电镜观察Aβ1-42在海马脑微血管壁的表达.结果:Morris水迷宫试验显示模型组与正常组比较,逃避潜伏时上升,穿越平台位置次数及平台象限游泳时间、路程所占总时间和总路程百分比下降(P＜0. 01或P＜0. 05),电针治疗组逃避潜伏时较模型组下降(P＜0. 01);ELISA检测海马Aβ1-42结果显示电针治疗组较模型组明显降低(P＜0. 01);免疫电镜结果显示电针治疗组脑微血管壁胶体金颗粒较模型组减少.结论:电针治疗可改善APP/PS1转基因小鼠空间认知能力,降低海马Aβ1-42水平,其机制可能与改善血脑屏障Aβ清除能力有关.