摘要
目的探讨人参皂苷Rg_1对D-半乳糖(D-gal)所致衰老小鼠海马的保护机制。方法 6~8周龄雄性C57BL/6J巢蛋白(Nestin)-绿色荧光蛋白(GFP)转基因小鼠随机分为4组,每组10只,分别为对照组、人参皂苷Rg_1对照组、人参皂苷Rg_1治疗组、模型组。衰老模型建立与给药完成后第2天,水迷宫实验检测小鼠空间学习记忆能力;取小鼠海马制备冷冻组织切片,观察海马区神经干细胞Nestin荧光强度;衰老相关β-半乳糖苷酶(SA-β-gal)染色法检测海马细胞衰老;酶标比色法检测海马组织匀浆中超氧化物歧化酶(SOD)活性、总抗氧化能力(T-AOC)和丙二醛(MDA)的量;ELISA检测海马组织匀浆中白细胞介素-1β(IL-1β)、IL-6与肿瘤坏死因子-α(TNF-α)的量;蛋白印迹法检测海马组织中p53、p21蛋白表达。结果与模型组比较,人参皂苷Rg_1对照组和人参皂苷Rg_1治疗组小鼠空间学习记忆能力明显增强;海马齿状回(DG区)Nestin荧光强度增高;海马齿状回(CA3区)SA-β-gal染色阳性细胞百分比显著降低;海马组织匀浆中SOD活性与T-AOC显著增加、MDA量下降;IL-1β、IL-6和TNF-α量减少;p53、p21蛋白表达降低。结论人参皂苷Rg_1具有拮抗D-gal所致衰老小鼠海马损伤和延缓海马衰老的作用,其机制可能与抑制氧化应激及下调其下游p53-p21信号通路有关。
Objective To investigate the protective mechanism of ginsenoside Rg1 on hippocampus of aging mice induced by D-galactose. Methods Forty nestin-green fluorescent protein（GFP） transgenic mice, aged 6—8 weeks, were randomly divided into four groups： control group, ginsenoside Rg1 control group, ginsenoside Rg1 therapy group, and model group. Learning and memory abilities were measured by Morris water maze after the modeling completed. Frozen sections were made to survey the hippocampus fluorescence intensity. Senescence-associated β-galactosidase（SA-β-Gal） staining was used to detect the aging level of hippocampus. The activities of superoxide dismutase（SOD）, total antioxidant capacity（T-AOC）, and contents of malonaldehyde（MDA） in hippocampus were tested by chromatometry. Enzyme-linked immunosorbent assay（ELISA） was used to test the levels of interleukin（IL）-1β, IL-6, and tumor necrosis factor（TNF）-α proinflammatory cytokins in hippocampus. The levels of p53 and p21 were detected by Western blotting. Results The learning and memory capacities of the aging model group were decreased compared with those of the drug therapy group; The fluorescence intensity in the dentat gyrus（DG） of hippocampus of the drug therapy group was increased compared with that of the model group; The SA-β-Gal positive granules in section of brain tissue of the aging model group were increased compared with those of the drug group and drug therapy group; The activitives of SOD and T-AOC of the drug therapy group were increased compared with those of the aging model group while the content of MDA was decreased. The levels of IL-1β, IL-6, and TNF-α were decreased in the drug therapy group compared with those in the aging model group. The levels of p53 and p21 were decreased in the drug therapy group compared with those in the aging model group. Conclusion Ginsenoside Rg1 can antagonistic D-galactose and delay the aging of hippocampus. In addition, improvement of anti-oxidant ability and regulation of the level of p53-p21 pathway may be the underlying anti-aging mechanism of ginsenoside Rg1.
出处
《中草药》
CAS
CSCD
北大核心
2017年第18期3789-3795,共7页
Chinese Traditional and Herbal Drugs
基金
国家自然科学基金资助项目(81673748)
国家教育部博士导师基金(20125503110006)
