Mode of action of a neuroprotective compound

 描述（由申请方提供）：NAD+耗竭导致脑缺血/再灌注损伤、沃勒变性、多发性硬化的啮齿动物模型中的神经元死亡，并发生在兴奋性毒性损伤和氧化应激后。我们最近发现，NAD+耗竭也是由错误折叠和毒性形式的淀粉样蛋白朊蛋白（TPrP）诱导的神经元死亡的主要原因。这些结果确立了NAD+耗竭在至少一种蛋白质错误折叠神经变性疾病的发病机制中的作用，所述神经变性疾病是包括阿尔茨海默病和帕金森病等的疾病家族。NAD+补充逆转了培养物中TPrP损伤的神经元的命运，并改善了朊病毒病小鼠模型的运动功能。在试验性高通量筛选中，我们鉴定了通过在TPrP暴露的细胞中补充NAD+来恢复神经元活力的化合物。我们假设其分子靶点是TPrP诱导途径中的关键效应子，并且破译该化合物的作用模式将进一步加深我们对TPrP毒性和可能的其他衰弱性脑疾病中普遍存在的NAD+耗竭机制的理解。在这项集中的研究工作中，我们将使用基于亲和力的方法与蛋白质组学相结合，以确定与其神经保护活性相关的化合物的分子靶标，确定其作用模式并探测其结构以增强活性。这些知识将提供与NAD+耗竭相关的退行性途径的见解，并将支持旨在开发神经保护药物的先导物开发工作。

 DESCRIPTION (provided by applicant): NAD+ depletion causes neuronal death in rodent models of brain ischemia/reperfusion injury, Wallerian degeneration, multiple sclerosis and occurs after excitotoxic insults and oxidative stress. We have recently discovered that NAD+ depletion is also the primary cause of neuronal death induced by a misfolded and toxic form of the amyloidogenic prion protein (TPrP). These results established the role of NAD+ depletion in the pathogenesis of at least one protein misfolding neurodegenerative disease, a family of diseases that comprise, among others, Alzheimer's disease and Parkinson's disease. NAD+ replenishment reversed the fate of TPrP- injured neurons in culture and improved motor function in a mouse model of prion disease. In a pilot high- throughput screen we identified a compound restoring neuronal viability by NAD+ replenishment in TPrP- exposed cells. We hypothesize that its molecular target is a key effector in the TPrP-induced pathway and that deciphering the compound's mode of action will further our understanding of the mechanisms of NAD+ depletion prevalent in TPrP toxicity and possibly other debilitating brain conditions. In this focused research effort, we will use affinity-based methods combined with proteomics to identify the compound's molecular target relevant to its neuroprotective activity, determine its mode of action and probe its structure for enhanced activity. This knowledge will provide insights into degenerative pathways linked to NAD+ depletion and will support lead development efforts aiming at developing a neuroprotective drug.