Aβ25-35联合D-半乳糖诱导树鼩AD模型的建立

Establishment of AD Model Using Aβ25-35 Combined with D-galactose in Tree Shrew

目的建立Aβ25-35联合D-半乳糖诱导的树鼩阿尔茨海默病模型,为进一步研究药物对AD的疗效及作用机制提供帮助。方法24只雄性树鼩随机分为四组(n=6):对照组、D-半乳糖组、Aβ25-35组、D-半乳糖组联合Aβ25-35(D+A)组。所有动物在立体定位仪下开颅,Aβ25-35组和D+A组海马注射Aβ25-35(4μL,5 mg/mL),对照组和D-半乳糖组注射等量生理盐水。术后D-半乳糖组和D+A组皮下注射D-半乳糖125 mg/(kg·d),对照组和Aβ25-35组给予生理盐水,连续8周。Morris水迷宫试验后,心脏采血处死树鼩,取大脑制成石蜡切片,免疫组化检测Aβ1-42的表达。结果在水迷宫试验中,与对照组比较,其他三组逃避潜伏期均极显著性延长、穿越平台次数差异有统计学意义(P<0.05)。D+A组的逃避潜伏期(P<0.05)和穿越平台的次数(P<0.05)较D、A组差异有统计学意义(P<0.01)。免疫组化显示,D、A、D+A组树鼩大脑皮层与海马Aβ1-42的表达显著高于对照组(P<0.05),而D+A组的Aβ1-42显著高于D组和A组(P<0.05)。结论相对于单因素给药,Aβ25-35联合D-半乳糖诱导是更为合适的树鼩AD造模方式。

Objective To establish Alzheimer's disease model using Aβ25-35 combined with D-galactose in tree shrew.Method 24 male tree shrew were randomly divided into control group(CT),D-galactose group(D),Aβgroup(A),D-galactose combined with Aβ25-35(D+A).Group A and D+A were injected Aβ25-35(4μL,5 mg/mL),the other two groups were injected with saline(4μL,5 mg/mL)into the hippocampus once.For group D and D+A,D-galactose 125 mg/(kg·d)was injected subcutaneously everyday after surgery,while the group CT and A were injected subcutaneously with the same dose of normal saline for 8 weeks.The water maze behavioral test was performed at the 9th week.After anesthesia,the brain was embedded in paraffin and sectioned.IHC was used to detect the expression of Aβ1-42.Results Compared with the control group,the escape latency in group D,A,and D+A was significantly prolonged(P<0.01),and was significantly longer in D+A group than that of group D and A(P<0.05).The number of crossing platforms was significantly lower in group D,A and D+A than that in CT group(P<0.05),and was significantly lower in D+A group than these in group D and A(P<0.05).Compared with the control group(P<0.05),the expression Aβ1-42 protein was significantly increased of the hippocampus and cortex in group D,A and D+A,and that was significantly high in the D+A group(P<0.05)than group D and A.Conclusion The compound factor model of AD has been established using Aβ25-35 combined with D-galactose in tree shrew.