Dopamine Toxicity and Mitochondrial Dysfunction

描述(申请人提供)：这项研究将集中在一个基本的问题上，即多巴胺的反应性代谢物是否可能有助于神经退行性疾病的发病机制，如帕金森病。多巴胺已被证明在体外和体内对细胞都有毒性。然而，与毒性相关的确切机制尚不清楚。由于线粒体在细胞死亡机制中起着关键作用，因此这些研究旨在增加我们对多巴胺反应性代谢产物与线粒体功能之间相互作用的了解，以及它们增强多巴胺能神经元对损伤的易感性的能力。在目标1中，我们将描述暴露于多巴胺后线粒体功能丧失和细胞死亡之间的时间关系。在目标2中，使用纹状体黑质器官型培养，我们将检查多巴胺能神经元是否表现出对线粒体抑制的增加的易感性，以及多巴胺是否参与了这一效应。最后，在目标3中，我们将使用质谱学来确定经多巴胺醌修饰和失活的关键蛋白质的身份，重点是线粒体蛋白质。这些研究的结果有可能确定新的治疗靶点，以阻止和防止帕金森氏病的神经退变过程。

DESCRIPTION (provided by applicant): This study will focus on the fundamental question of whether reactive metabolites of dopamine, may be contributing to the pathogenesis of neurodegenerative disorders such as Parkinson's disease. Dopamine has been shown to be toxic to cells both in vitro and in vivo. However, the exact mechanism associated with the toxicity is not known. Because mitochondria play a critical role in mechanisms of cell death, the proposed studies are designed to increase our understanding of the interplay between reactive metabolites of dopamine and mitochondrial function, and their ability to enhance the vulnerability of dopaminergic neurons to injury. In Aim 1, we will characterize the temporal relationship between loss of mitochondrial function and cell death following exposure to dopamine. In Aim 2, using striatonigral organotypic cultures, we will examine whether dopaminergic neurons exhibit an increased vulnerability to mitochondrial inhibition and whether dopamine contributes to this effect. Finally, in Aim 3, we will determine the identity of critical proteins modified and inactivated by dopamine quinones using mass spectrometry, with a focus on mitochondrial proteins. The outcome of these studies has potential for identifying new therapeutic targets for stopping and preventing the neurodegenerative process in Parkinson's disease.