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，但大多数晚发型病例的确切病因 阿尔茨海默病（LOAD）尚不清楚。随后，治疗 AD 的疗法基本上不成功。 AD 的两个重要危险因素：衰老和饮食，其中衰老是 AD 的最大危险因素，在很大程度上仍然存在 被忽略。饮食限制（DR）是延缓衰老最有力的干预措施之一，也可以延缓衰老的发生 跨物种的多个模型中的阿尔茨海默病（AD）。我们利用了短寿命和强大的 黑腹果蝇中鉴定芥末 (mtd)/氧化应激抗性蛋白 1 (OXR1) 的遗传工具 DR 对寿命的保护作用需要在神经元中存在。重要的是，我们观察到 OXR1 防止果蝇和人诱导多能干细胞 (iPSC) 中与年龄相关的神经变性 神经退行性疾病模型。 OXR1 预防神经退行性变的机制 仍不清楚。我们观察到抑制 OXR1 会减少逆转录酶蛋白，同时增强逆转录酶 功能，挽救抑制 OXR1 的有害影响。此外，我们发现 OXR1 和 使用蛋白质组学数据，几种逆转录酶蛋白与人类 AD 风险增加相关 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， 我们建议测试 OXR1 增强逆转录酶功能以延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。第一个目标，我们将确定监管机制 OXR1 及其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 OXR1 在增强逆转录酶功能中的 DR 依赖性作用以及逆转录酶在介导 DR的保护作用。确定 OXR1 增强 DR 后逆转录酶功能的机制；我们 将使用蛋白质组学来确定和表征 OXR1 的蛋白质结合伴侣。在第三个目标中，我们将 测试 OXR1 在 AD 模型中防止神经变性的作用，并通过增强逆转录酶 功能。我们将测试 OXR1 是否在过度表达人类 tau 或 tau 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度表达 OXR1 和逆转录酶蛋白 衍生 AD iPSC 并测量 AD 终点：Aβ42/40 积累、细胞死亡和电生理学。 由于 OXR1 在果蝇中调节逆转录酶功能，我们将评估该调节在果蝇中是否保守。 人类 AD 衍生的 iPSC 并进行组学方法来识别介导 OXR1 的关键信号通路 保护作用。通过表征 OXR1 调节的逆转录酶功能和蛋白质网络及其在 衰老和年龄依赖性神经退行性疾病，我们将为开发减缓衰老的疗法提供新的靶点 AD 相关病理并延长健康寿命。此外，我们将确定是否重复使用蛋白质 在营养限制条件下通过逆转录酶具有神经保护作用并延缓衰老。

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.