S14G-Humanin对Aβ_(31-35)所致大鼠行为学及神经元凋亡的影响

Effects of S14G-Humanin on Aβ_(31-35)-induced dysfunction of learning and memory and neuronal apoptosis in rat

目的:研究S14G-Humanin对Aβ31-35所致大鼠行为学及神经元凋亡的影响。方法:SD大鼠60只随机分为5组,经侧脑室分别注入生理盐水(对照组)、Aβ31-35(Aβ31-35组),Aβ31-35+HNG(0.01 mmol/L),Aβ31-35+HNG(0.1 mmol/L)和Aβ31-35+HNG(1 mmol/L)。注射第7 d行Morris水迷宫实验观察各组大鼠的行为学改变;注射12 d后处死大鼠,应用TUNEL法检测各组海马神经元的凋亡情况,应用免疫组化法检测神经元caspase-3的表达。结果:与对照组相比,Aβ31-35组大鼠的学习、记忆能力明显下降(P<0.05),Aβ31-35+HNG(0.1,1 mmol/L)组大鼠的学习、记忆能力有所改善,与Aβ31-35组相比差异有统计学意义(P<0.05)。Aβ31-35组海马神经元的凋亡指数及caspase-3阳性细胞数均高于正常对照组,Aβ31-35能引起大鼠海马神经元的凋亡及学习、记忆能力的下降;Aβ31-35+HNG(1,0.1,0.01 mmol/L)组凋亡指数及caspase-3阳性细胞数均明显下降,与Aβ31-35组相比差异有统计学意义(P<0.05)。结论:S14G-Humanin对Aβ31-35诱导的大鼠海马神经元凋亡及行为学改变具有保护作用。

Objective：To observe the effects of S14G-Humanin on Aβ31-35-induced dysfunction of learning and memory and neuronal apoptosis in rat.Methods：60 SD rats were randomly divided into five groups.Saline,Aβ31-35 and Aβ31-35＋HNG（1,0.1,0.01 mmol/L）were respectively given by intracerebroventricular injection（i.c.v）.The Morrois water maze was done in the 7th day after i.c.v to observe the rat’s ability of learning and memory,then killed the rats in the 12th day and neuronal apoptosis was analyzed by caspase-3 and TUNEL staining.Results：Compared with the control group,the ability of leaning and memory was declined in Aβ31-35 group（P〈0.05）.Compared with the Aβ31-35 group,the ability of leaning and memory was improved in Aβ31-35＋HNG groups（1,0.1 mmol /L）（P〈0.05）.Compared with the control group,positive cells of caspase-3 and apoptosis index were increased in Aβ31-35 group（P〈0.05）.Compared with the Aβ31-35 group,positive cells of caspase-3 and apoptosis index were decreased in HNG groups（1,0.1,0.01 mmol/L,P〈0.05）.Conclusion：Aβ31-35 can induce impairment of leaning and memory and neuronal apoptosis.However,S14G-Humanin can protect against behavioral deficits and neuronal apoptosis induced by Aβ31-35