Mechanisms of Manganese Neurotoxicity

说明(申请人提供)：锰是一种强效的神经毒素。我们假设，PARK2，一个强大的帕金森病(PD)遗传风险因子，改变了神经元对细胞锰状态修饰物的易感性，特别是在线粒体功能障碍和氧化应激的水平上。这项研究的长期目标是阐明锰诱导的神经毒性的基础，并确定基于机制的神经保护策略来降低人类锰暴露的风险。我们的方法将利用一种新的细胞内锰水平的高通量分析来识别细胞内锰状态和神经毒性的小分子修饰物。将定义锰运输和毒性的遗传修饰物，并利用基于人类诱导多能干细胞(HiPSC)技术的原代人类神经元模型系统，对现有的和新发现的锰毒性遗传修饰物和小分子修饰物进行翻译研究。目的1利用纹状体和中脑小鼠神经细胞系在体外和体内利用线虫鉴定能够改变神经元锰转运和毒性的先导化合物。目的2将描述体内和体外调节锰转运和毒性的功能通路。具体目标3将测试这一假设，即帕金森病的人类神经元模型对细胞锰状态的扰动表现出更高的敏感性。这些特定的目标有望描绘出调节锰神经毒性的共同启动信号，揭示与接触这种金属相关的机制和易感性。这一双PI建议得到了在不同型号系统中使用创新的最先进的互补方法的支持。

DESCRIPTION (provided by applicant): Manganese (Mn) is a potent neurotoxin. We hypothesize that PARK2, a strong Parkinson's disease (PD) genetic risk factor, alters neuronal vulnerability to modifiers of cellular Mn status, particularly at the level of mitochondrial dysfunction and oxidative stress. The long-term goal of this research is to elucidate the basis of Mn-induced neurotoxicity and to identify mechanistic-based neuroprotective strategies to mitigate human Mn exposure risk. Our approach will utilize a novel high-throughput assay of intracellular Mn levels to identify small molecule modifiers of cellular Mn status and neurotoxicity. Genetic modifiers of Mn transport and toxicity will be defined and translational studies of existing and newly identified genetic and small molecule modifiers of Mn toxicity will be performed utilizing a primary human neuronal model system based upon human induced pluripotent stem cell (hiPSC) technology. Aim 1 will identify lead compounds that alter neuronal Mn transport and toxicity in vitro using striatal and mesencephalic murine neuronal cell lines and in vivo using C. elegans. Aim 2 will delineate functional pathways that regulate Mn transport and toxicity in vivo and in vitro. Specific Aim 3 will test the hypothesis that human neuronal models of PD exhibit increased sensitivity to perturbations of cellular Mn status. These specific aims hold the promise of delineating common initiator signals for the modulation of Mn neurotoxicity, shedding light on mechanisms and susceptibility associated with exposure to this metal. This dual-PI proposal is bolstered by its use of innovative state-of-the-art complimentary approaches in diverse model systems.