谷胱甘肽对血管性痴呆小鼠的神经保护作用研究

Nerve protective effect of glutathione in vascular dementia mice

目的探讨谷胱甘肽(GSH)对血管性痴呆(VaD)小鼠的保护作用及机制。方法筛选高通量基因表达数据库(GEO)中检索人类VaD患者基因表达芯片数据,获得19例样本,VaD患者8例,健康对照者11例,通过GEO 2R选出表达有显著差异的基因,采用火山图和聚类图分析调控GSH分子谷氨酸转运蛋白表达变化。选择C57BL/6J雄性成年小鼠42只,随机分为假手术组6只,VaD组、GSH 50组和GSH 100组,后3组各12只,并建立VaD模型,后2组于术后即刻分别腹腔注射GSH 50、100 mg/kg,1次/d,连续15 d后,采用水迷宫实验检测3组小鼠学习记忆能力,之后取材,采用尼氏染色检测海马区神经元损伤程度。结果火山图和聚类图分析显示,VaD患者较健康对照者谷氨酸转运蛋白基因表达显著下降(P<0.01)。水迷宫实验显示,与假手术组比较,VaD组第1、2和3天平均逃避时间显著延长(P<0.01),而GSH 100组较VaD组第2和3天平均逃避时间显著缩短(P<0.05,P<0.01)。甲苯胺蓝染色显示,与假手术组比较,VaD组、GSH 50组和GSH 100组小鼠海马CA3区神经元阳性细胞数量显著减少[(48.83±3.88)个/HP、(52.00±2.81)个/HP和(64.33±2.81)个/HP vs(81.17±3.41)个/HP,P<0.01];其中GSH 100组小鼠较VaD组显著升高(P<0.01),而GSH 50组与VaD组比较无显著差异(P>0.05)。结论 GSH通过减轻海马神经元损伤,实现对VaD的神经保护作用。

Objective To study the nerve protective effect of glutathione(GSH) in VaD mice and its molecular mechanism.Methods The gene expression chip data in VaD patients were retrieved from the GEO database.The differentially expressed genes were selected from the GEO 2 R.The expression of GSH molecule-related genes in VaD patients was detected by volcano map and cluster map.Forty-two C57 BL/6 male adult mice were randomly divided into sham operation group(n=6),VaD group(n=12),GSH(50 mg/kg) group(n=12) and GSH(100 mg/kg) GSH group(n=12).A VaD model was established.The animals in GSH(50 mg/kg) group and GSH(100 mg/kg) group were intra-abdominally injected with GSH(50 mg/kg) and GSH(100 mg/kg)(once a day) for 15 days after operation.The learning and memory of mice were tested by Morris water maze test.The damage of neurons in hippocampus was observed with toluidine blue staining.Results Gene chip expression profiling analysis showed that the expression level of glutamate transporter was significantly lower in VaD patients than in healthy controls(P<0.01).The mean escape time was significantly longer in VaD group than in sham operation group on days 1-3(P<0.01).Toluidine blue staining revealed that the number of positive neurons in hippocampal CA3 area was significantly smaller in VaD group,GSH(50 mg/kg) group and GSH(100 mg/kg) group than in sham operation group(48.83±3.88/HP,52.00±2.81/HP,64.33±2.81/HP vs 81.17±3.41/HP,P<0.01),and was significantly greater in GSH(100 mg/kg) group than in VaD group(P<0.01).However,no significant difference was detected in the number of positive neurons in hippocampal CA3 area between GSH(50 mg/kg) group and VaD group(P>0.05).Conclusion GSH can protect the nerves by alleviating the damage of neurons in hippocampus.