预防性绿茶多酚干预对帕金森病小鼠多巴胺能神经元的保护作用

Protective effect of green tea polyphenols on substantia nigra dopaminergic neurons in Parkinson's disease old mice induced by MPTP

目的探索预防性绿茶多酚(GTPs)干预对MPTP诱导的帕金森病(PD)小鼠黑质多巴胺能神经元保护作用及机制。方法采用C57BL/6J老年小鼠共60只,分为空白对照组、预防组、神经毒素1-甲基-4苯基-1,2,3,6-四氢吡啶(MPTP)组和治疗组(n=15)。后三组分别给予MPTP建立模型和绿茶多酚干预后免疫组化法观察黑质多巴胺能神经元数量,比色法观察中脑氧化应激水平。结果预防组、MPTP组和治疗组黑质多巴胺能神经元数量显著减少(P<0.01),氧化应激水平明显升高(P<0.01),但变化幅度预防组<治疗组<MPTP组。结论预防性补充抗氧化物质对PD小鼠的多巴胺神经元具有优于治疗的保护作用,其机制可能为预先增强抗氧化应激能力,提高发生病理改变的阈值。

Objective To investigate the preventive effect of green tea polyphenols( GTPs) on substantia nigra dopaminergic neurons of MPTP inducing Parkinson's disease( PD) old mice. Methods C57BL /6J old mice( n = 60) were divided into pre GTPs + MPTP, post GTPs + MPTP,MPTP only and control groups equally. Mice in pre GTPs + MPTP group were given water mixing GTPs for 3 months before they were injected intraperitoneally with 30 mg / kg MPTP each day for 7 consecutive days,in post GTPs + MPTP group were treated reversely. Mice in MPTP only group were only injected MPTP by the above-mentioned way. Mice in control group were only injected with normal saline. Immunohistochemical analysis was used to detected tyrosine hydroxylase( TH). Superoxide dismutase( SOD) and malonaldehyde( MDA) were determined to measure oxidative stress. Results The order for different expression levels of TH decreasing and oxidative stress increasing was: pre GTPs + MPTP group < post GTPs + MPTP group < MPTP only group. Conclusions Antioxidations Suppletion has more obviously protective effect on PD mice dopamine neurons. The possible mechanisms are to enhance prior antioxidant stress ability and improve the threshold value of pathological changes.