镇肝熄风汤对帕金森病小鼠黑质多巴胺能神经元的保护作用

Protective effect of Zhengan Xifeng Decoction on dopaminergic neurons in the substantia nigra in MPTP-treated C57BL/6 mice

目的:观察镇肝熄风汤对1-甲基-4-苯基-1,2,3,6-四氢吡啶(1-methy-4-phenyl-1,2,3,6-tetrahydropyridine,MPTP)诱导的C57BL/6小鼠黑质神经元凋亡的保护作用及其可能机制。方法:C57BL/6小鼠皮下注射MPTP(30mg/kg)制备帕金森病小鼠模型,灌胃给予镇肝熄风汤预处理。运用爬杆试验检测小鼠的运动协调能力,采用Annexin V-FITC双染法测定细胞凋亡率,实时定量RT-PCR法检测α-突触核蛋白(α-Syn)mRNA表达,分光光度法检测caspase-3酶活性。结果:与模型组比较,镇肝熄风汤可显著缩短帕金森病小鼠爬杆时间(P<0.05),抑制黑质多巴胺能神经元凋亡(P<0.05),下调α-Syn mRNA表达,减少caspase-3酶活性(P<0.05)。结论:镇肝熄风汤具有抗实验性帕金森病的作用,其机制可能与抑制α-Syn介导的黑质多巴胺能神经元凋亡有关。

Objective： To investigate the protective effect of Zhengan Xifeng Decoction on dopaminergic neurons in the substantia nigra from toxicity of MPTP in C57BL/6 mice, and some possible involved mechanisms. Methods： C57BL/6 mice were given MPTP （30mg/kg） to prepare parkinson disease mice model. Different doses of Zhengan Xifeng Decoction （12.5, 25, 50g/kg）, or selegiline （10mg/kg） were given 10 days prior to MPTP in the pretreatment groups. Climbing pole test was used to estimate the movement coordination of mice. Apoptosis of neurons were determined by Annexin V-FITC/PI staining. Real-time PCR was used to analyze the expression of α-synuclein mRNA. Caspase-3 activity in the brain was determined by spectrophotometry. Results： Compared with model group, Zhengan Xifeng Decoction could diminish average time of climbing pole in MPTP-treated C57BL/6 mice in climbing pole test （P〈0.05）; Zhengan Xifeng Decoction could also protect against neurons apoptosis in the substantia nigra （P〈0.05）, down-regulate the expression of α-synuclein mRNA, and decrease caspase-3 activation （P〈0.05）. Conclusion： Zhengan Xifeng Decoction exerted anti-parkinson disease effect in mice via depression apoptosis of dopaminergic neurons in the substantia nigra, and this effect might be attributable to regulation mRNA expression of α-synuclein.