目的构建D-半乳糖(D—galactose,D—gal)致衰老模型,探讨D-gal诱导衰老的分子机制,为临床治疗阿尔茨海默病(AD)提供理论依据.方法大鼠腹腔注射D—gal 100mg/(kg.d)×56d造模.第50~56天进行Morris水迷宫实验(MWM);第57天取脑组织,生物化学方法分光光度法检测大脑海马一氧化氮合酶(NOS)、一氧化氮(NO)、铜锌-过氧化物岐化酶(Cu,Zn—SOD)、总超氧化物歧化酶(T—SOD)、谷胱甘肽还原酶(GR)、谷胱甘肽S-转移酶(GSH—ST)、谷胱甘肽过氧化酶(GSH—PX)、谷胱甘肽(GSH)、丙二醛(MDA),总抗氧化能力(T—AOC)和过氧化氢(H2O2)的表达水平.结果模型大鼠较正常大鼠逃避潜伏期明显延长(P〈0.05),在第Ⅲ象限逗留的时间明显减少(P〈0.05),跨越平台次数明显减少(P〈0.05),海马内MDA、H2O2和NO表达增加,SOD、GSH、GSH—ST、GSH-Px、T—AOC表达降低,而NOS表达没有明显变化(P〉0.05).结论D—gal能通过调控内源性巯基抗氧化物(酶),减退学习记忆能力,诱导大鼠神经系统的衰老。
Objective To underlying investigate the mechanisms of the aging induced by D-galactose, we used D-galactose to establish aging rat model. Methods Aging rats model were established by peritoneal injection of D-Galactose ( 100 mg/kg, 56 days) into the rats. Then, we examined spatial memory with the morris water maze, and the extent of oxidative stress biomarkers including malondialdehyde (MDA) , total antioxidative capabilities (T-AOC) , total superoxide dismutase (T-SOD) , and glutathione peroxidase (GSH-Px) activities in hippocampus. Results Chronic systemic exposure of D-galactose to rats induced a spatial memory deficit and increased cerebral oxidative stress, including an increase in malondialdehyde (MDA), hydrogen peroxide (H2O2), nitric oxide (NO), while a decrease in total anti-oxidative capabilities (T-AOC),total superoxide dismutase (T-SOD) , glutathione (GSH) , glutathione peroxidase (GSH-Px) , glutathione-s-transferase (GSH-ST) activities. Conclusion The present results suggest that chronic D-galactose exposure can induce a spatial memory deficit and aging of central nervous system by manipulating thiol antioxidants and NO of the hippocampus in rats.