Matsuzaki Michiko, Hasegawa Takafumi, Takeda Atsushi, Kikuchi Akio, Furukawa Katsutoshi, Kato Yoji, Itoyama Yasuto
Department of Neurology, Tohoku University School of Medicine, 1-1 Seiryo-Machi, Aoba, Sendai 980-8574, Japan.
Brain Res. 2004 Apr 9;1004(1-2):83-90. doi: 10.1016/j.brainres.2004.01.017.
alpha-Synuclein is a major component of intracytoplasmic inclusions including Lewy bodies (LB), Lewy neurites (LN) and glial cytoplasmic inclusions, and plays a key role in neurodegenerative processes in Parkinson's disease (PD) and other synucleinopathies. Although the molecular mechanisms of the disease process still remain to be elucidated, recent studies have suggested that an interaction between reactive oxygen species (ROS) and alpha-synuclein may be closely associated with the initiation and/or the progression of synucleinopathies. In this study, we established human dopaminergic SH-SY5Y cell lines overexpressing wild-type or mutant alpha-synuclein and exposed them to various ROS generators. After the exposure to ROS, alpha-synuclein aggregates were formed in the cytoplasm of these cells, and these were immunopositive for ubiquitin, nitrotyrosine and dityrosine, and positive for thioflavin S staining. Thus, the obtained cytoplasmic aggregates shared many features with inclusion bodies in synucleinopathies. The gamma-tubulin and molecular chaperones coexisted as well, suggesting that the aggregate formation is associated with the intracellular transport along microtubules and may reflect protective responses against neuronal insults. This cellular model not only will be informative for our understanding of the pathophysiological process in synucleinopathies, but also can be applied to the screening of neuroprotective molecules with therapeutic potential.
α-突触核蛋白是胞浆内包涵体的主要成分，包括路易小体（LB）、路易神经突（LN）和胶质细胞胞浆内包涵体，在帕金森病（PD）和其他突触核蛋白病的神经退行性过程中起关键作用。尽管疾病过程的分子机制仍有待阐明，但最近的研究表明，活性氧（ROS）与α-突触核蛋白之间的相互作用可能与突触核蛋白病的起始和/或进展密切相关。在本研究中，我们建立了过表达野生型或突变型α-突触核蛋白的人多巴胺能SH-SY5Y细胞系，并将它们暴露于各种ROS生成剂。暴露于ROS后，这些细胞的细胞质中形成了α-突触核蛋白聚集体，这些聚集体对泛素、硝基酪氨酸和二酪氨酸呈免疫阳性，对硫黄素S染色呈阳性。因此，所获得的细胞质聚集体与突触核蛋白病中的包涵体具有许多共同特征。γ-微管蛋白和分子伴侣也共存，这表明聚集体的形成与沿微管的细胞内运输有关，可能反映了对神经元损伤的保护反应。这种细胞模型不仅将有助于我们理解突触核蛋白病的病理生理过程，而且可应用于筛选具有治疗潜力的神经保护分子。
