摘要
目的探讨不同剂量的表没食子儿茶素没食子酸酯(EGCG)对哺乳期铅暴露仔鼠海马学习记忆能力损伤的作用,及对β淀粉样蛋白、脑啡肽酶的影响。方法选取SPF级C57BL/6孕鼠,随机分为对照组和铅暴露组。铅暴露组孕鼠在哺乳期饮用0.5%醋酸铅水溶液,对照组饮用蒸馏水。染铅结束后,取40只染铅雄性仔鼠(分为低、中、高剂量EGCG干预组、铅暴露模型组,每组各10只),对照组10只雄性仔鼠,分别用不同浓度的EGCG溶液和生理盐水等体积灌胃21 d,采用Morris水迷宫实验检测各组小鼠学习记忆能力,石墨炉原子吸收光谱法测定各组小鼠血铅含量,并对海马组织中Aβ1-40、Aβ1-42、AβPP mRNA、AβPP、脑啡肽酶(Nep)的蛋白含量进行测定。结果铅暴露模型组,低、中、高剂量EGCG干预组的血铅含量明显高于对照组(P<0.001),低、中、高剂量EGCG干预组和铅暴露模型组血铅含量比较差异无统计学意义(P=0.174,0.086,0.071);铅暴露模型组逃避潜伏期高于对照组(P<0.001),中、高剂量EGCG干预组的逃避潜伏期低于铅暴露模型组(P<0.001);铅暴露模型组小鼠海马内Aβ1-40、Aβ1-42的含量与对照组比较明显升高(P<0.001),Nep含量明显降低(P<0.001),中、高剂量EGCG干预组Aβ1-40、Aβ1-42的含量与铅暴露模型组比较明显降低,Nep含量明显升高(P<0.001),其中以高剂量EGCG干预组效果最佳。结论 EGCG干预能明显提高小鼠的学习记忆能力,且EGCG能够降低小鼠海马组织中Aβ1-40、Aβ1-42的含量,抑制Aβ相关基因AβPP的表达,上调Nep蛋白的表达。
Objective To explore the effects of different doses of epigallocatechin 3 gallate,table gallic catechin gallic acid ester（ EGCG） on the learning and memory ability,amyloid beta and neprilysin enzymes in lactation mice which were exposed to lead. Methods SPF pregnant C57 BL /6 mice were divided into control group（ drank distilled water,n = 4） and lead exposure group（ drank 0. 5% Pb-contaminated acetic acid solution,n = 14）. Another 40 male lead-exposed mice were divided into 4 groups,lowEGCG group（ 1. 5 mg / kg）,which are moderate EGCG group（ 3. 0 mg / kg）,high EGCG group（ 4. 5 mg / kg） and lead exposure group,with 10 mice in each group. Another 10 male mice served as the control group（ normal saline）. After 21 days of treatment,all rats＇ learning and memory ability was tested with Morris water maze experiment; the lead content in blood and hippocampus was determined with graphite furnace atomic absorption spectrometer; the protein contents of Aβ1-40,Aβ1-42,AβPP mRNA,AβPP and the neprilysin enzyme were also detected. Results The lead exposure group,and low,moderate and high EGCG groups had significantly higher content of blood lead than the control group（ P〈0. 05）. There was no difference among EGCG groups and lead exposure group（ P = 0. 174,0. 086,0. 071）. Lead exposure group had longer escaping latency than the control group（ P 〈0. 001）,while the EGCG group had shorter escaping latency than the control group（ P 〈0. 001）. Compared with the control group,the lead exposure group had increased content of Aβ1-40 and Aβ1-42（ P〈 0. 001）,and decreased Nep content（ P 〈0. 001）; the moderate and high EGCG groups had decreased Aβ1-40 and Aβ1-42 content and increased Nep content（ P〈 0. 001）,and the high EGCG group had better interventional effect. Conclusion EGCG intervention can significantly improve the learning and memory ability of mice. EGCG can reduce Aβ1-40 and Aβ1-42 contents in the hippocampus,inhibit the expression of related gene AβPP
出处
《山东大学学报（医学版）》
CAS
北大核心
2016年第12期8-13,共6页
Journal of Shandong University:Health Sciences
基金
国家自然科学基金(81172716)
