GAPDH的聚集及异常降解在帕金森病发病机制中作用的研究

项目名称： GAPDH的聚集及异常降解在帕金森病发病机制中作用的研究

项目编号： No.30870866

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 环境科学、安全科学

项目作者： 王涛

作者单位： 华中科技大学

项目金额： 32万元

中文摘要： 中脑黑质多巴胺能神经元选择性变性和神经元内Lewy小体形成是帕金森病（PD）的主要病理生理特征。国内外的研究发现，3-磷酸甘油醛脱氢酶（GAPDH）与神经元凋亡关系密切。我们的前期研究工作也发现，PD中存在着GAPDH的结构改变和异常聚集，GAPDH也是Lewy小体样包涵体的重要组份。但关于GAPDH异常聚集的启动和加重的原因、GAPDH降解通路的改变、以及GAPDH的聚集对细胞功能的影响尚未阐明。本项目在原有的工作基础上，运用realtime-PCR、western blot、RNA干扰、非还原SDS-PAGE、免疫荧光等技术，深入研究GAPDH异常修饰和聚集的原因；使用泛素蛋白酶体及溶酶体通路的特异性抑制剂和激活剂处理，了解PD中GAPDH降解途径的变化。研究发现，1，在帕金森病细胞及动物模型中，均存在着GAPDH的过表达及异常聚集；2，GAPDH异常聚集的可能原因是在氧化及硝化应激状况下形成了二硫键结合的多聚体，并导致其糖酵解酶活性的下降，最终导致神经元死亡；3，GAPDH不是以往认为的只经由自噬溶酶体途径降解，其也通过泛素蛋白酶体途径降解。

中文关键词： 帕金森病；3-磷酸甘油醛脱氢酶；Lewy小体；凋亡

英文摘要： The pathophysiological hallmarks of Parkinson's disease (PD) are the progressive degeneration of dopaminergic neurons in the substantia nigra and the formation of cytoplasmic Lewy bodies. Recently, a close relationship between glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and neuronal apoptosis has been suggested. Our preliminary study has shown that there were structural changes and abnormal aggregation of GAPDH in PD model. GAPDH is also an important component of lewy body-like inclusions. However, the cause of GAPDH aggregation, the dysfunction of GAPDH degradation pathway and the effect on cell death are still obscure. In this project, we further focused on the cause of GAPDH modification and aggregation using molecular biology techniques like realtime-PCR, western blot, RNA interference, non-reduced SDS-PAGE and immunofluorescence et al. The change of GAPDH degradation pathway was also investigated using specific inhibitors and activators of ubiquitin-proteasome pathway and lysosome pathway. Our research found that:1.There is GAPDH overexpression and abnormal aggregation in PD models;2.The apoptosis of dopaminergic cells caused by GAPDH aggregation is possibly due to the disulfide bonding and glycolytic activity inhibtion of GAPDH under oxidative and nitrative stresses.3.Degradation of GAPDH was not only through the lysosomal pathway as previously reported, but also degredated through the ubiquitin proteasomal pathway in our research.

英文关键词： Parkinson's disease; Glyceraldehyde-3-phosphate dehydrogenase; Lewy body; apoptosis