Genistein对MPTP致帕金森病去势模型小鼠多巴胺能神经元保护作用及其机制研究

The Study of Protective Effects of Genistein on the Dopaminergic Neurons in the Mato-induced Ovx Mouse Modle of PD

目的研究大豆异黄酮活性成分genistein对1-甲基-4-苯基-1,2,3,6-四氢吡啶(1-methy-4-phenyl-1,2,3,6-tetrahydropyridine,MPTP)制备的去卵巢(OVX)帕金森病(Parkinson's disease,PD)模型小鼠多巴胺能神经元的保护作用及其可能机制。方法雌性C57BL6小鼠行双侧去卵巢手术(OVX)后,分为对照组、MPTP组、genistein预处理组和雌激素预处理组。采用逆转录-聚合酶链式反应(RT-PCR)、免疫组织化学染色以及图像分析等技术分别对黑质致密带(substantial nigra pars compacta,SNpc)多巴胺转运蛋白(dopaminetransporter,DAT)、bcl-2等指标的mRNA及蛋白质的表达水平进行考察。结果 Genistein及雌激素用药组SN内DAT、bcl-2 mRNA及其蛋白的表达水平较MPTP组显著升高(P<0.01),差异有统计学意义。结论 Genistein对MPTP制备的PD模型小鼠黑质DA能神经元有明显的保护作用,其作用机制可能与抗凋亡有关。

Objective To investigate the neuroprotective effect of genistein on dopaminergic neurons on ovariecto-mized （OVX）, 1- methyl-4 -phenyl -l, 2, 3, 6 -tetrahydropyridine （MPTP） induced PD model mice and its mechanism. Method The study consisted of control group, MPTP group （ 30 mg/kg x 5 d） , genistein （ 10 mg/kg x 8 d） and estrogen （50 mg/kg x 8 d） group. C57BL mice were ovariectomized and administrated i. p. with MPTP to estab- lish PD model. The pretreatment groups were given i. p. with genistein and estradiol benzoate for 3 days prior to MPTP in- jection. Then using semi -quantitive reverse transcriptase- polymerase chain reaction （RT- PCR） to observe the expres- sion of DAT, bcl - 2 gene in the substantia uigra pars compacta （SNpc）. The expression of DAT, bcl - 2 protein in the SNpc was investigated by the immunohistochemistry （ICC） method. Results Pretreatment with genistein or estrogen sig- nificantly antagonized MPTP - induced losses of DAT, bcl - 2 - protein expression in the SNpc. MPTP - challenge with genistein or estrogen pretreatment demonstrated reduced neurotoxicity, with DAT, bcl - 2 mRNA expression in the SN ap- parently higher than that of MPTP group （ P 〈 0. 05 ）. Conclusion The protective effects of genistein are obvious on the dopaminergic neurons in the MPTP - induced OVX mouse model of PD, and the mechanism possibly related to apoptosis. All these results could provide experimental evidence for the clinical application of genistein to prevent and treat PD.