电针联合天麻素对阿尔茨海默病大鼠海马CA 1区沉默信息调节因子2同源蛋白1和过氧化物酶体增殖物激活受体γ辅激活子1 ɑ表达的影响

Electroacupuncture plus Gastrodin Improves Learning-memory Ability Possibly by Up-regulating Expression of SIRT 1 and PGC-1 α in Hippocampal CA 1 Region of Alzheimer's Disease Rats

目的:探讨电针联合天麻素治疗阿尔茨海默病(AD)的作用机制。方法:SD大鼠随机分为正常组、假手术组、模型组、电针组、天麻素组和针药联合组,每组10只。腹腔注射D-半乳糖联合双侧海马注射β淀粉样蛋白1-40制备AD大鼠模型。电针组和针药联合组给予"百会""大椎"、双侧"足三里"穴电针刺激,每次30min,1次/d,连续4周;天麻素组和针药联合组腹腔注射天麻素注射液,每日1次,连续4周。Morris水迷宫检测各组大鼠学习记忆能力;尼氏染色观察海马CA 1区神经元形态;免疫组织化学法检测各组大鼠海马CA 1区沉默信息调节因子2同源蛋白1(SIRT 1)和过氧化物酶体增殖物激活受体γ辅激活子(PGC-1ɑ)的表达。结果:Morris水迷宫结果显示,与正常组及假手术组比较,模型组大鼠逃避潜伏期延长(P<0.05),平台象限停留时间百分比、穿台次数降低(P<0.05);与模型组比较,电针与天麻素及联合使用均可降低AD大鼠的逃避潜伏期(P<0.05),提高平台象限停留时间百分比(P<0.05),增加穿台次数(P<0.05);针药联合组的效果优于电针组及天麻素组(P<0.05)。尼氏染色结果显示,与正常组及假手术组比较,模型组大鼠海马CA 1区神经元数量减少,排列紊乱;各治疗组CA 1区神经元数量较模型组明显增多,排列规则。与正常组及假手术组比较,模型组大鼠海马CA 1区SIRT 1和PGC-1ɑ阳性表达水平降低(P<0.05);与模型组比较,电针组和天麻素组CA 1区SIRT 1和PGC-1ɑ阳性表达水平升高(P<0.05);针药联合组的表达水平高于电针组和天麻素组(P<0.05)。结论:电针与天麻素均能够改善AD大鼠的学习记忆能力,且电针联合天麻素的效果更为显著,提示其可能通过上调海马SIRT 1和PGC-1ɑ蛋白的表达,发挥对AD大鼠神经元的保护作用。

Objective To observe the effect of electroacupuncture （EA） combined with Gastrodin on learning-memory ability and expression of silent information regulator 2 homologous protein 1 （SIRT 1） and peroxisome proliferator activated recep- tor y coactivator （PGC-1 a） of hippocampal CA 1 region in Alzheimer＇s disease（AD） rats, so as to explore its mechanism under- lying improvement of AD. Methods Sixty male SD rats were randomly divided into normal control （normal）, sham operation （sham）, model, EA, Gastrodin and EA ＋ Gastrodin groups （n = 10 in each）. The AD model was established by intraperitoneal in- jection of D-Galactose （120 mg · kg-1 · d-1） combined with bilateral hippocampal injection of β amyloid 1-40（Aβ 1-40）. EA was applied at ＂Baihui＂（GV 20）, ＂Dazhui＂（GV 14） and ＂Zusanli＂（ST 36） for 30 min, once daily for 4 weeks. For rats of the Gastro-din group and EA＋ Gastrodin group, intraperitoneal injection of gastrodin（10 mg/kg） was conducted once daily for 4 weeks. Mor- ris water maze tests were used to assess the rat^s learning-memory ability. Nissl staining was used to assess the morphological changes of neurons in the hippocampal CA 1 area. The expression of SIRT 1 and PGO-1 a of hippocampal CA 1 region was mea- sured by immunohistochemical staining. Results 1） Morris water maze tests showed that, compared with the normal and sham group, the escape latency was significantly prolonged （P^0.05）, and the percentage of platform quadrant residence duration and the platform crossing times were considerably decreased in the model group （P〈0.05）. After the intervention, the escape laten- cy was obviously shortened （P〈0.05）, and the percentage of platform quadrant residence duration and the platform crossing times were markedly increased in the EA, Gastrodin and EA ＋ Gastrodin groups relevant to the model group （P〈0.05）. 2） Nissl staining showed that, in comparison with the normal group or sham group, the number of cells in the hippocampal CA 1 area was decreased and the arrangement was disorganized in the model group. The number of cells in CA 1 area was relatively higher in the 3 treatment groups than in the model group. 3） The expression levels of SIRT 1 and PGC-1 a proteins in the hippocampal CA 1 area were significantly down-regulated in the model group than in the normal and sham groups （P〈0.05）. After the intervention, the expression levels of SIRT 1 and PGC-1 a in the EA, Gastrodin and EA＋ Gastrodin groups were significantly up-regulated compared with the model group （P〈0.05）. The effects of EA ＋ Gastrodin were significantly superior to those of simple EA and simple Gastrodin in shortening the escape latency, up-regulating the expression levels of SIRT 1 and PGC-1 a as well as in increasing the percentage of platform quadrant residence time and platform crossing times （P〈0.05）. Conclusion Both EA and Gastrodin can improve the learning-memory ability of AD rats, which may be related to their effects in up-regulating the expression of SIRT 1 and PGC-1 a and reducing neuronal injury in the CA 1 region of hippocampus, suggesting a protective role of EA on hippocampal neurons. The effect of EA combined with Gastrodin is markedly better than that of EA and Gastrodin alone.