茶多酚及其提取物EGCG抑制MPTP致α-突触核蛋白聚集  

Inhibitive effects on MPTP induced alpha-synuclein aggregation by tea polyphenols and EGCG

作　　者：于兰[1,2] 陈敏[1,2] 李旭冉[1,3] 李昕[1,3] 杨巍巍[1,3] 于顺[1,3,4] 

机构地区：[1]首都医科大学宣武医院神经生物学研究室,北京100053 [2]桂林医学院解剖学教研室,桂林541004 [3]帕金森病研究北京重点实验室,北京100053 [4]北京脑重大疾病研究院帕金森病研究所,北京100053

出　　处：《首都医科大学学报》2015年第5期680-683,共4页Journal of Capital Medical University

基　　金：国家重点基础研究发展计划(2011CB504101);国家自然科学基金(81071014;81371200;81401042);国家科技支撑计划课题(2012BAI10B03);北京市自然科学基金(7122035);首都卫生发展科研专项课题(2011-4001-01)~~

摘　　要：目的研究茶多酚及其提取物表没食子儿茶素没食子酸酯（epigallocatechin-3-gallate,EGCG）对帕金森病神经毒素1-甲基-4-苯基-1,2,3,6-四氢吡啶（1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,MPTP）引起的α-突触核蛋白（α-synuclein,α-syn）聚集的影响。方法健康雌性食蟹猴（10~12岁）,采用数字表法随机分为正常对照组、茶多酚对照组（TP组）、帕金森病模型组（MPTP组）和茶多酚治疗组（MPTP＋TP组）,每组4只。正常对照组不进行任何处理;茶多酚对照组灌胃给予茶多酚80 d;帕金森病（Parkinson＇s disease,PD）模型组静脉给予MPTP诱导PD模型;茶多酚治疗组在PD模型建立后给予茶多酚治疗80 d。实验动物经安乐死后,分离脑组织,ELISA法检测不同脑区寡聚化α-syn含量。体外培养MES23.5多巴胺能神经细胞,细胞外添加α-syn单体或寡聚体后,再经MPP＋和/或EGCG处理,ELISA法检测细胞内α-syn寡聚体的量,MTT法检测各组多巴胺能神经细胞损伤情况。结果 MPTP增加猴脑组织寡聚化α-syn含量,治疗性给予茶多酚减少MPTP引起的α-syn聚集。体外研究表明,MPP＋可明显增加对照组、α-syn单体和寡聚体处理组细胞的细胞内α-syn寡聚体的量,而茶多酚提取物EGCG可以抑制MPP＋引起的细胞内α-syn聚集,并缓解MPP＋所致细胞损伤。结果茶多酚及其提取物EGCG可以抑制PD神经毒素MPTP引起α-syn聚集和多巴胺能神经元损伤。Objective To investigate the inhibitive effects of tea polyphenols（ TP） and their extract epigallocatechin-3-gallate（ EGCG） on-synuclein aggregation in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine（ MPTP）-intoxicated Parkinson＇s disease. Methods Healthy female 10 to 12 years old cynomolgus monkeys were randomly divided into normal control group（ n = 4）,TP group（ n = 4）,MPTP group（ n = 4）,and MPTP ＋ TP group（ n = 4）. Control group monkeys were not given any treatment; The monkeys in TP group were treated with TP by gastrogavage once daily for 80 consecutive days. In MPTP and MPTP ＋ TP groups,MPTP was injected intravenously as MPTP-HCl to induce PD model. The MPTP ＋ TP groups were treated with TP by gastrogavage once daily for 80 consecutive days after establishing PD model. All animals were euthanized and the brains tissues were rapidly isolated. The level of α-syn oligomers were measured by the ELISA method. In vitro,MES23. 5 dopaminergic neurons treated with α-syn monomers or oligomers,followed by treatment with vehicle MPP ＋ and（ or） EGCG. Intracellular levels of α-syn oligomers were measured by ELISA. Cell viability was estimated using the MTT formazan colorimetric assay. Results MPTP-intoxication could increase the levels of α-syn oligomers and TP administration could reduce α-syn oligomers in the brain of MPTP-treated monkeys. In vitro study demonstrated while addition of MPP＋ significantly elevated intracellular levels of α-syn in untreated control group and groups treated with α-syn monomers and α-synoligomers. The capacity of the extract EGCG to reduce-syn oligomerization was further examined and alleviated the MPP ＋ induced cell injury in cultured cells. Conclusion The tea polyphenols and its extract EGCG could alleviate-syn aggregation and dopaminergic neuronal injury caused by MPTP-intoxication.

关 键 词：茶多酚 Α-突触核蛋白 多巴胺能神经元细胞 

分 类 号：R338[医药卫生—人体生理学]