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

项目总结/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，并且与2-4倍。 老年痴呆症和相关痴呆症的发病率增加1 -5。TBI表现为进行性 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、减缓或逆转神经变性的慢性进展， TBI后AD加速在许多神经退行性疾病中，包括AD，帕金森病， 在亨廷顿氏病中，异常线粒体分裂已被确定为 发病机制7.它也与脑震荡性TBI 8 -10的急性阶段有关。该项目的目标是 表征急性和慢性TBI中发生的线粒体分裂调节的变化， 确定TBI后限制性异常高线粒体分裂是否提供了 TBI和TBI诱导的加速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TBI小鼠模型： 1.确定TBI如何影响线粒体关键介质的表达、修饰和活性， 分裂，动力蛋白相关蛋白1（Drp 1）。我将在一个全面的列表中测量Drp 1的表达 脑损伤后早期和晚期的脑区。我还会测量翻译后 修饰、寡聚化活性和Drp 1调节蛋白的表达。 2.确定急性TBI后线粒体分裂的药物抑制如何减轻病理 TBI后急性和慢性时间点的症状。我会给受伤的老鼠注射P110， 关键线粒体分裂蛋白Drp 1的小肽抑制剂， 确定在TBI中具有神经保护作用，然后研究一系列 组织学测量、透射电子显微镜观察的超微结构变化以及生物能量学测量。 通过Seahorse分析。 3.确定P110治疗在减轻TBI诱导的阿尔茨海默病加速中的功效。 我将在轻度TBI后对5xFAD小鼠施用P110，并使用行为测试来确定 P110在减少加速性神经认知缺陷中的功效。我还将使用组织学方法， 监测作为TBI和P110治疗的函数的斑块沉积的变化。 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、生物化学测定以及共聚焦和电子显微镜。我也会培养 与神经变性相关领域的研究人员合作，并发展对该领域的临床见解 神经退行性疾病这份建议书概述了一个严格的培训计划，我将通过该计划建立所需的技能 作为一名神经退行性疾病和神经精神病学领域的医生科学家，

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.