The role of mitochondrial fission in neurodegeneration in the leading environmental cause of Alzheimer's disease

项目摘要/摘要 在过去的十年中，创伤性脑损伤(TBI)的发病率一直在上升，并与2-4倍的 阿尔茨海默病和相关痴呆的发病增加1-5岁。脑损伤呈进行性 以认知缺陷和神经精神障碍为特征的神经退行性损伤4，6。目前， 没有可用的治疗方法来预防、减缓或逆转神经退行性变的慢性进展和 颅脑损伤后AD加速。在许多神经退行性疾病中，包括阿尔茨海默病，帕金森氏病， 亨廷顿病，线粒体的异常分裂已被确定为 致病因素7.它也与脑震荡的急性期有关。这个项目的目标是 [目的]研究急性和慢性脑损伤中线粒体分裂调控的变化，并探讨 确定在药物上限制脑损伤后异常高的线粒体分裂是否提供了 脑外伤和脑损伤所致加速性AD的神经保护策略。 为了实现我的目标，我提出了以下目标，使用已建立的脑外伤小鼠模型： 1.确定脑损伤对线粒体关键介质的表达、修饰和活性的影响 裂变，动力蛋白相关蛋白1(Drp1)。我将在一个全面的列表中测量Drp1的表达 脑损伤后早期和晚期脑区的变化。我还将测量翻译后的 Drp1调节蛋白的修饰、寡聚活性和表达。 2.确定急性脑外伤后对线粒体分裂的药物抑制如何减轻病理 以及急性和慢性时相点的症状。我会用p110给受伤的小鼠用药， 关键线粒体分裂蛋白Drp1的小肽抑制物，已经 确定在脑外伤中具有神经保护作用，然后研究一系列 组织学测量、透射电子显微镜超微结构变化和生物能量学 通过SeaHorse分析进行更改。 3.确定p110治疗对减轻脑损伤所致阿尔茨海默病加速的疗效。 我将在轻度脑损伤后给p110至5xFAD小鼠注射，并使用行为测试来确定 P110‘S降低加速性神经认知功能障碍的疗效。我还会用组织学的方法 监测斑块沉积随脑损伤和p110治疗的变化。 通过完成这个项目，我将获得新的实验室技术，包括行为测试， 免疫组织化学、生化分析、共聚焦显微镜和电子显微镜。我也会扶植 与神经变性相关领域的研究人员合作，发展对该领域的临床洞察力 神经退行性变。这份建议概述了一项严格的培训计划，我将通过该计划来建立所需的技能 作为一名神经退行性疾病和神经精神病学领域的内科科学家而获得成功的职业生涯。

Project Summary/Abstract In the past decade, traumatic brain injury (TBI) has been rising in incidence, and is linked to a 2-4 fold increase in developing Alzheimer's disease and related dementias later in life1–5. TBI presents as a progressive neurodegenerative injury characterized by cognitive deficits and neuropsychiatric impairment4,6. Currently, there are no available treatments to prevent, slow, or reverse the chronic progression of neurodegeneration and accelerated AD after TBI. In many neurodegenerative conditions, including AD, Parkinson's disease, Huntington's disease, aberrant mitochondrial fission has been identified as a critical component of pathogenesis7. It has also been implicated in the acute stages of concussive TBI8–10. The goals of this project are to characterize the changes in regulation of mitochondrial fission that occur in acute and chronic TBI, and to determine whether pharmacologically limiting aberrantly high mitochondrial fission after TBI provides a neuroprotective strategy for TBI and TBI-induced accelerated AD. To address my goal, I propose the following aims, using an established mouse model of TBI: 1. Determine how TBI affects expression, modification, and activity of the key mediator of mitochondrial fission, dynamin-related protein 1 (Drp1). I will measure expression of Drp1 across a comprehensive list of brain regions at early and late timepoints after TBI. I will also measure post-translational modifications, oligomerization activity, and expression of regulatory proteins of Drp1. 2. Determine how pharmacologic inhibition of mitochondrial fission after acute TBI mitigates pathology and symptoms at acute and chronic timepoints after TBI. I will administer injured mice with P110, a small peptide inhibitor of the key mitochondrial fission protein Drp1 which has already been determined to be neuroprotective in TBI, and then investigate pathological changes across an array of histological measures, ultrastructural changes via transmission electron microscopy, and bioenergetic changes via Seahorse analysis. 3. Determine the efficacy of P110 treatment in mitigating TBI-induced acceleration of Alzheimer's disease. I will administer P110 to 5xFAD mice following mild TBI, and use behavioral testing to determine P110's efficacy in reducing accelerated neurocognitive deficits. I will also use histological methods to monitor changes in plaque deposition as a function of TBI and P110 treatment. Through completing this project, I will acquire new lab techniques, including behavioral testing, immunohistochemistry, biochemical assays, and both confocal and electron microscopy. I will also foster collaboration with researchers in related fields of neurodegeneration, and develop clinical insight into the field of neurodegeneration. This proposal outlines a rigorous training plan by which I will establish the skills needed for a successful career as a physician-scientist in the fields of neurodegeneration and neuropsychiatry.