Determining the role of OXR1 in aging and Alzheimer's disease

项目概要/摘要 尽管确定了AD的一些遗传风险因素，但大多数迟发性阿尔茨海默病病例的确切病因仍不清楚。 阿尔茨海默病（LOAD）是未知的。随后，治疗AD的疗法在很大程度上不成功。 AD的两个重要风险因素，衰老和饮食，其中衰老是AD的最大风险因素， 忽视饮食限制（DR）是减缓衰老的最有力的干预措施之一，也延迟了衰老的发生。 阿尔茨海默病（AD）在多个模型跨物种。我们利用了短寿命和强大的 遗传工具在D.黑腹菌鉴定芥子气（mtd）/氧化应激抗性蛋白1（OXR 1） 是DR对寿命的保护作用所必需的。重要的是，我们观察到OXR 1 在果蝇和人类诱导的多能干细胞（iPSC）中保护年龄相关的神经变性 神经退行性疾病的模型。OXR 1保护神经变性的机制 仍不清楚我们观察到抑制OXR 1减少了逆转录酶蛋白，同时增强了逆转录酶的表达。 功能，挽救抑制OXR 1的有害作用。此外，我们发现OXR 1和 几种逆转录蛋白质与人类AD风险增加有关， 来自加速药物计划-阿尔茨海默病（AMP-AD）网络的1000多名AD患者。在这里， 我们建议验证OXR 1增强逆转录酶功能以减缓衰老和神经退行性变的假设 使用AD的果蝇和人类iPSC模型。在第一个目标中，我们将确定 OXR 1以及它如何影响衰老和与年龄相关的神经元损伤。在第二个目标中，我们将确定 OXR 1在增强retromer功能中的DR依赖性作用以及retromer在介导 为了确定OXR 1增强DR后retromer功能的机制，我们研究了OXR 1对DR的保护作用。 将使用蛋白质组学来确定和表征OXR 1的蛋白质结合伴侣。第三个目标，我们将 测试OXR 1在AD模型中保护神经退行性变的作用，并通过增强逆转录聚合酶链反应来检测OXR 1在AD模型中保护神经退行性变的作用。 功能我们将测试OXR 1是否在过表达人tau蛋白的果蝇模型中调节AD病理学， β淀粉样蛋白（Aβ）。我们将在前脑胆碱能和皮质神经元中过表达OXR 1和retromer蛋白， 我们的方法是使用来自AD iPSC的细胞，并测量AD终点：Aβ42/40积累、细胞死亡和电生理学。 由于OXR 1调节果蝇中的retromer功能，我们将评估这种调节在果蝇中是否保守。 并进行组学方法以鉴定介导OXR 1的关键信号传导途径 保护作用。通过表征由OXR 1调控的逆转录功能和蛋白质网络及其在 衰老和年龄依赖性神经退行性变，我们将为开发治疗方法提供新的靶点，以减缓 AD相关的病理和延长健康寿命。此外，我们将确定蛋白质的重复使用是否 通过retromer在营养限制条件下是神经保护和延缓衰老。

PROJECT SUMMARY/ABSTRACT Despite identifying some of the genetic risk factors for AD, the precise etiology of most cases of Late-Onset Alzheimer's disease (LOAD) is unknown. Subsequently, therapies to treat AD have been largely unsuccessful. Two important risk factors for AD, aging, and diet, with aging being the greatest risk factor for AD, remain largely ignored. Dietary restriction (DR), one of the most robust interventions to slow aging, also delays the onset of Alzheimer’s disease (AD) in multiple models across species. We exploited the short lifespan and powerful genetic tools in D. melanogaster to identify that mustard (mtd)/oxidative stress resistance protein 1 (OXR1) in neurons is required for the protective effects of DR on lifespan. Importantly, we have observed that OXR1 protects against age-related neurodegeneration in fly and human-induced pluripotent stem cell (iPSC) derived models of neurodegenerative diseases. The mechanisms by which OXR1 protects against neurodegeneration remains unclear. We observed that inhibiting OXR1 reduces retromer proteins while enhancing retromer function, rescues the deleterious effects of inhibiting OXR1. Furthermore, we found that alterations in OXR1 and several retromer proteins are associated with an increased risk of AD in humans using proteomics data from over 1000 AD patients from the Accelerating Medicines Program-Alzheimer’s Disease (AMP-AD) network. Here, we propose to test the hypothesis that OXR1 enhances retromer function to slow aging and neurodegeneration using fly and human iPSC models of AD. In the first aim, we will determine the mechanisms of regulation of OXR1 and how that influences aging and age-related neuronal damage. In the second aim, we will determine the DR-dependent role of OXR1 in enhancing retromer function and the role of retromer in mediating the protective effects of DR. To determine the mechanism by which OXR1 enhances retromer function upon DR; we will use proteomics to determine and characterize the protein binding partners of OXR1. In the third aim, we will test the role of OXR1 in protecting against neurodegeneration in models of AD, and by enhancing retromer function. We will test whether OXR1 modulates AD pathology in fly models that overexpress human tau or amyloid β (Aβ). We will overexpress OXR1 and retromer proteins in forebrain cholinergic and cortical neuron derived AD iPSCs and measure AD endpoints: Aβ42/40 accumulation, cell death, and electrophysiology. Because OXR1 regulates retromer function in the fly, we will evaluate whether this regulation is conserved in human AD-derived iPSCs and carry out omics approaches to identify key signaling pathways mediating OXR1’s protective effects. By characterizing retromer function and protein networks regulated by OXR1 and their role in aging and age-dependent neurodegeneration, we will provide novel targets for developing therapeutics to slow AD-related pathologies and extend healthspan. Furthermore, we will determine whether reuse of proteins through retromer under nutrient limiting conditions is neuroprotective and slows aging.