OXIDATIVE STRESS IN PARKINSON'S DISEASE

特发性帕金森病（PD）是一种主要的神经退行性疾病，影响至少100万美国人，PD的细胞原因尚未确定。 该提案将进一步探索中心假设，即线粒体电子传递链（ETC）功能缺陷是PD中细胞过早死亡的主要原因，并将解决四个具体目标：1）定义线粒体转换孔功能的病理生理学，以及膜电位和细胞内钙信号传导的调节如何在PD中改变; 2）确定PD胞质杂交体中Bcl蛋白调节的机制，以及用Bcl过表达载体转染是否改变线粒体功能并改善存活; 3）进一步确定PD中MAP激酶信号通路和NF κ B转录因子之间的相互作用;和4）表征从人死后PD脑分离的线粒体过渡孔复合物，并将它们的功能与从对照脑分离的那些进行比较。 该项目将利用最先进的细胞内离子成像技术，RT-PCR技术，基因转染策略，并将开发无细胞系统来检查几个相互关联的假设。 在所有这些实验室实验的背后是一种治疗的必要性，这将在细胞和无细胞模型中进行探索。 由于本申请中提出的新数据支持PD患者全身性氧化应激增加的假设，因此在已建立的细胞模型中探索这些事件更加引人注目。该提案还将比较PD胞质杂交体与暴露于慢性鱼藤酮治疗的SY 5 Y细胞中的发现，这是一种基于药理学细胞的复合物I损失模型。 最终，从这个建议的结果将建立遗传获得性线粒体ETC功能障碍作为散发性PD的病因因素的核心重要性。 评估神经保护疗法的范例也将被开发，以允许有针对性的方法来纠正细胞中氧化应激增加的后果。

Idiopathic Parkinson's Disease (PD) is a major neurodegenerative disease affecting at least 1 million Americans, and the cellular cause of PD is not yet known with certainty. This proposal will explore further the central hypothesis that defects in mitochondrial electron transport chain (ETC) function are a major contributor to premature cell death in PD and will address four Specific Aims 1) define the pathophysiology of mitochondrial transition pore function, and how regulation of membrane potential and intracellular calcium signaling are altered in PD; 2) determine mechanisms of Bcl protein regulation in PD cybrids, and whether transfection with Bcl-overexpression vectors alters mitochondrial function and improves survival; 3) further define the interactions among MAPKinase signaling pathways and NFkappaBeta transcription factor in PD; and 4) characterize mitochondrial transition pore complexes isolated from human postmortem PD brain and compare their function to those isolated from control brain. This project will make use of state-of-the- art intracellular ion imaging technology, RT-PCR techniques, gene transfection strategies, and will develop cell-free systems to examine several inter-related hypotheses. Behind all of these laboratory experiments is a therapeutic imperative, which will be explored in cell and cell-free models. Because new data presented in this application supports the hypothesis of systemically increased oxidative stress in PD patients, exploring these events in an established cell model is even more compelling. This proposal will also compare findings in PD cybrids with those in SY5Y cells exposed to chronic rotenone treatment, a pharmacological cell-based model of complex I loss. Ultimately, the results from this proposal will establish the central importance of genetically acquired mitochondrial ETC dysfunction as an etiologic factor in sporadic PD. Paradigms for evaluating neuroprotective therapies will also be developed to allow targeted approaches to correcting consequences of increased oxidative stress in cells.