银杏黄酮抑制Aβ_(1-42)聚集和纤维形成的分子机制  

Inhibition of ginkgo flavones against aggregation and fibrogenesis of Aβ_(1-42)

作　　者：李光武[1] 任振华[1] 王培源[1] 唐敏[1] 汪华侨[2] 

机构地区：[1]安徽医科大学神经生物学研究所,安徽合肥230032 [2]中山大学医学院解剖系脑研究室,广东广州510080

出　　处：《中成药》2007年第6期797-801,共5页Chinese Traditional Patent Medicine

基　　金：国家自然科学基金(No:30470904);安徽省教委自然基金(No:2003KJ226)

摘　　要：目的:探讨EGb761中银杏黄酮、银杏内酯抑制Aβ聚集和纤维形成药物作用的分子机制。方法:用园二色谱(CD)和傅里叶变换红外光谱法(FT-IR)曲线拟合定量分析和特征频谱分析Aβ老化后和银杏黄酮、银杏内酯分别干预后二级结构的变化。结果:通过1700～1600cm-1之间的酰胺Ⅰ带和曲线拟合分析,Aβ1-42单独孵育30min到72h,β-折叠片增加了18.50,与银杏黄酮、银杏内酯孵育72h,β-折叠片的含量下降了50.95,36.09,β-转角的含量升高56.56,46.56。呈现出明显的β折叠片向β-转角的转化。基团特征峰谱位显示,酮类和烷烃类的-CH2和-CH参与了Aβ1-42的分子变构。结论:EGb761中银杏黄酮可能是通过抑制Aβ1-42β-折叠形成,Aβ1-42肽侧链基团发生了化学修饰达到抑制Aβ聚集和纤维形成作用。AIM： To gain the molecular mechanism of active ingredients of EGb 761 （ginkgo flavones and ginkgo lides） for the inhibition against Aβ1-42 aggregation and fibrogenesis. METHODS： Circular dichroism spectra （CD） and FI-IR were used to curve-fit and analyze the change in Aβ1-42 second structure under Aβ aged condition and intervention of ginkgo flavones and ginkgo lides. RESULTS： Analysis that was made of 1700 -1600 m^-1 amide- Ⅰ -band and curve fitting indicated that after 30 min to 72-incubation, increase of β-sheet in Aβ1-42 by 18.5%, but the reduction of β-sheet by 50.95% and 36.09% in 72 h incubation with ginko flavones and ginkgo lides, respectively. And increase of β-turn by 56.56% and 46.56% in sane condition. CONCLUSION ： Obviously, β-sheet turned into β-turn. -CH2 and -CH groups of ketones and alkanes engaged in Aβ1-42 molecular change.

关 键 词：Aβ1-42聚集 老年性痴呆 Β-折叠 银杏黄酮 

分 类 号：R285.6[医药卫生—中药学]