五味子乙素对D-半乳糖致衰老小鼠学习记忆能力的改善作用

Schisandrin B Improves D-Galactose-Induced Learning and Memory Impairment in Aging Mice

目的:观察五味子乙素(schisandrin B,SCB)对D-半乳糖致衰老小鼠学习记忆能力的改善作用。方法:ICR小鼠随机分为4组,即正常对照组(灌胃蒸馏水,皮下注射生理盐水)、衰老模型组(灌胃蒸馏水,皮下注射220mg/kg D-半乳糖)、SCB(M)组(灌胃20mg/kg?SCB,皮下注射D-半乳糖220mg/kg)、SCB(C)组(灌胃20mg/kg?SCB,皮下注射生理盐水),连续给药7周。通过避暗实验及Morris水迷宫实验观察SCB对小鼠学习记忆能力的影响;通过WST-1法检测小鼠脑组织中超氧化物歧化酶(superoxide dismutase,SOD)活力;通过硫代巴比妥酸法检测小鼠脑组织中丙二醛(malondialdehyde,MDA)含量;通过实时定量聚合酶链式反应及Western?blot法,检测小鼠脑组织中p19、p53、p21基因表达情况。结果:SCB能够明显改善D-半乳糖诱导的脑衰老小鼠的学习记忆能力,提高脑衰老小鼠脑组织中SOD活力,降低MDA水平,明显降低脑组织中的p19、p53、p21基因的表达水平。结论:SCB能够改善D-半乳糖诱导的小鼠脑衰老,该作用可能与其提高小鼠抗氧化能力及下调小鼠脑组织中p19、p53、p21基因表达水平有关。

Objective： To observe whether schisandrin B （SCB） can improve D-galactose-induced learning and memory impairment in aging mice. Methods： ICR mice were randomly divided into normal control group （intragastrically administered with distilled water and subcutaneously injected with normal saline）, aging model group （intragastrically administered with distilled water and subcutaneously injected with 220 mg/kg D-galactose）, SCB （M） group （intragastrically administered with 20 mg/kg SCB and subcutaneously injected with 220 mg/kg D-galactose）, and SCB （C） group （intragastrically administered with 20 mg/kg SCB and subcutaneously injected with normal saline）. The administration lasted for 7 weeks. Step-through test and Morris water maze test were applied to observe the effect of SCB on the learning and memory capacity of mice. The superoxide dismutase （SOD） activity in the brain tissue of mice was detected by the WST-1 method and the malondialdehyde （MDA） content was measured by the TBA method. The mRNA and protein expression of p19, p53 and p21 genes were detected by quantitative real-time PCR and Western blot, respectively. Results： SCB could significantly improve the learning and memory ability of D-galactose-induced aging mice, increase the SOD activity in the brain tissue, decrease the MDA level, and reduce the expression of p19, p53 and p21 genes. Conclusion： SCB can improve brain aging induced by D-galactose in mice, and the mechanism may be related to the increased antioxidant capacity and the decreased expression of p19, p53 and p21 genes in the brain tissue of mice.