Mitochondrial Sirtuin 3 in Parkinson's disease

摘要 本应用的总体目的是研究α-突触核蛋白(α-syn)诱导的机制 路易体病(LBD)的线粒体功能障碍。尽管它主要定位在细胞质中， αSYN定位于死后LBD脑中的线粒体。在线粒体内，αSYN的积累可以 损害复合体I和IV的功能，降低膜电位，增加活性氧水平， 并增加与线粒体释放细胞色素c相关的细胞凋亡。将这些数据放在一起 提示线粒体αSYN表达增加和/或有毒聚集体异常堆积 干扰线粒体功能。保持线粒体健康是防止神经细胞的关键 大脑中的死亡。Sirtuin 3(SIRT3)是一种依赖NAD的蛋白去乙酰基酶，仅定位于 线粒体，它调节线粒体的过程，包括蛋白质去乙酰化，细胞器 生物发生和氧化应激。SIRT3在大脑和其他神经系统中高水平表达 组织，并可作为促生存因子，在保护神经元方面发挥重要作用 神经退行性变模型中兴奋性毒性和挽救神经元丢失的条件。实验证据 提示SIRT3诱导的氧化应激神经保护作用部分是通过增强 线粒体的生物发生和完整性。当我们考虑以sirtuin为基础的药物疗法治疗 衰老，重要的是确定调节SIRT3是否可以防止神经退行性变，在哪里 线粒体功能障碍已被证明起到了一定作用。这项提案将调查如何 线粒体SIRT3在αSYN诱导的线粒体功能障碍中起3个协同作用。在目标1中 我们将进行全面的线粒体功能分析，以揭示αSYN的积累是如何导致 利用患者来源细胞和死后脑研究线粒体损伤和SIRT3在其中的作用。在……里面 目的2我们将询问sirt3调控的乙酰组，以确定α的新靶点。 线粒体功能障碍，在目标3中，我们将验证SIRT3作为治疗干预的新靶点 在帕金森病中，利用基因过表达和药理激活的综合体内方法。 拟议的对线粒体各个方面的严格分析将从原因和后果中剖析出来 揭示α、syn、sirt3和线粒体信号通路以及氧化和转录因子之间的相互作用 蛋白质应激反应。

ABSTRACT The overall aim of this application is to investigate mechanisms of alpha-synuclein (αsyn)-induced mitochondrial dysfunction in Lewy body diseases (LBD). Despite its predominant localization in the cytosol, αsyn localizes to mitochondria in post-mortem LBD brains. Within the mitochondria, αsyn accumulation can impair complex I and IV function, decrease membrane potential, increase levels of reactive oxygen species, and increase apoptosis associated with cytochrome c release from the mitochondria. Together these data suggest an increase in mitochondrial αsyn expression and/or abnormal accumulation of toxic aggregates interferes with mitochondrial function. Maintaining mitochondrial health is essential to prevent neuronal cell death in the brain. Sirtuin 3 (SIRT3) is a NAD+-dependent protein deacetylase exclusively localized to the mitochondria where it regulates mitochondrial processes including protein deacetylation, organelle biogenesis, and oxidative stress. SIRT3 is expressed at high levels in the brain and other nervous system tissues, and can act as a pro- survival factor, playing an essential role in protecting neurons under conditions of excitotoxicity and rescuing neuronal loss in neurodegenerative models. Experimental evidence indicates that SIRT3- induced neuroprotection against oxidative stress is partially mediated by enhancement of mitochondrial biogenesis and integrity. As we consider sirtuin-based drug therapies for diseases of ageing, it is important to determine if modulating SIRT3 can protect against neurodegeneration where mitochondrial dysfunction has been demonstrated to play a role. This proposal will investigate how mitochondrial SIRT3 contributes to αsyn-induced mitochondrial dysfunction in 3 coordinated aims. In aim 1 we will perform comprehensive mitochondrial function analyses to reveal how αsyn accumulation leads to mitochondrial damage and the role of SIRT3 therein using patient-derived cells and postmortem brain. In aim 2 we will interrogate the SIRT3 regulated acetylome to identify novel targets of αsyn-associated mitochondrial dysfunction, and in aim 3 we will validate SIRT3 as a novel target for therapeutic intervention in PD in a comprehensive in vivo approach using genetic overexpression and pharmacological activation. The proposed rigorous analysis of various mitochondrial aspects will dissect causes from consequences and reveal the cross-talk between αsyn, SIRT3, and mitochondrial signaling pathways as well as oxidative and protein stress responses.