INVESTIGATING THE ROLE OF THE CYTOSKELETON IN NEURODEGENERATION

研究细胞骨架在神经变性中的作用

• 批准号: 10678644
• 负责人: Morgan Catherine Stephens
• 金额: $ 4.77万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10678644
• 关键词: 70-kDa Ribosomal Protein S6 Kinases; Actins; Adult; Affect; Alzheimer' s Disease; Alzheimer' s disease brain; Alzheimer' s disease patient; American; Automobile Driving; Autophagocytosis; Behavior; Behavioral; Biochemical; Biological Assay; Biological Models; Brain; Cause of Death; Cell model; Cells; Clinical; Color; Communication; Complex; Cytoskeleton; Data; Dementia; Dendritic Spines; Deposition; Development; Disease; Disease Progression; Distal; Drosophila genus; Environment; Etiology; Genes; Genetic; Genetic Screening; Goals; Harvest; Histologic; Histology; Human; Human Cell Line; Huntington Disease; Impairment; In Vitro; LIM Domain; Lysosomes; Malignant Neoplasms; Measures; Mediating; Microfilaments; Microscopy; Modeling; Modification; Molecular; Mus; Nerve Degeneration; Neurodegenerative Disorders; Neurofibrillary Tangles; Neuronal Dysfunction; Neurons; Parkinson Disease; Pathogenesis; Pathology; Pathway interactions; Phase; Phosphotransferases; Prevalence; Process; Proteins; Regulation; Research; Resolution; Rod; Role; Senile Plaques; Societies; Synapses; System; Tauopathies; Techniques; Therapeutic; Therapeutic Intervention; Transmission Electron Microscopy; Ubiquitin; United States; Vesicle; Western Blotting; actin depolymerizing factor; attenuation; brain tissue; cofilin; combat; density; disability; extracellular; histological studies; hyperphosphorylated tau; improved; in vitro Assay; in vivo; induced pluripotent stem cell; insight; knock-down; misfolded protein; mouse model; multicatalytic endopeptidase complex; nerve stem cell; neurodegenerative phenotype; neuroinflammation; neuropathology; neurotoxic; new therapeutic target; novel; overexpression; prevent; protein aggregation; protein degradation; proteostasis; response; tau Proteins; tau aggregation; therapeutic development; therapeutic target; trafficking; vesicle transport; wasting

Project Summary/Abstract: Neurodegenerative diseases are among the fastest growing clinical burdens on society, and in the next 20 years Alzheimer’s Disease (AD) is projected to overtake cancer as the second leading cause of death in adults. Despite AD prevalence, there are currently no therapeutic interventions to combat the underlying pathology driving disease progression. While much is still not understood about neurodegenerative pathogenesis, the accumulation of extracellular amyloid- plaques and intracellular tau tangles are undisputed hallmarks of AD. To combat disease progression, an attractive therapeutic strategy is to investigate impairments in native proteostatic mechanisms used to dispose of this neurotoxic protein accumulation. One such mechanism which has been implicated in the development and progression of not only AD, but numerous neurodegenerative proteinopathy disorders including Parkinson’s and Huntington’s disease, is the autophagy-lysosomal network (ALN). The ALN is a bulk degradative system utilizing vesicular transport to dispose of large protein aggregates which contribute to neuronal dysfunction. This process relies on the active remodeling of the actin cytoskeleton to initiate, capture, and transport neurotoxic cargo for degradation and maintain proper proteostasis. However, mechanistically how dysregulations in cytoskeletal dynamics are associated with neurodegenerative pathology contributing to disease remains unclear. Through multiple behavioral neurodegenerative screens, we have identified an actin depolymerizing factor, cofilin, along with its upstream molecular regulators, which upon modulation improve neurodegenerative behavioral deficits and lower tau accumulation in vivo. This proposal seeks to investigate how cytoskeletal dynamics contribute to AD through genetic attenuation of the cofilin-centric cytoskeletal remodeling pathway. I hypothesize that modulating the activity of cofilin and its regulators will ameliorate AD neurodegenerative phenotypes via modification of the cytoskeleton and proteostasis. Aim 1 will utilize behavioral and histological approaches to investigate how genetic modulation of numerous genes within the remodeling pathway influence neurodegenerative phenotypes in tauopathy Drosophila and mouse models. In Aim 2, I will investigate mechanistically how this cytoskeletal remodeling pathway is involved in the formation and progression of the ALN through 1) measuring changes in neurotoxic protein accumulation upon cytoskeletal genetic modulation using various tauopathy model systems, and 2) utilizing high resolution microscopy techniques in AD patient derived induced pluripotent stem cells (iPSCs) along with biochemical in vitro assays, to investigate how genetically modulating cofilin disrupts various phases of the ALN. Upon successful completion of this project, we will identify molecular impairments of cytoskeletal remodeling associated with neurodegeneration that are involved in proteostatic imbalances and disease pathogenesis. Furthermore, we hope to identify novel therapeutic targets within this pathway capable of treating not only AD, but multiple neurodegenerative diseases caused by neurotoxic protein accumulation.

项目摘要/摘要： 神经退行性疾病是社会增长最快的临床负担之一，在未来 20 年 阿尔茨海默病 (AD) 预计将超过癌症，成为成人第二大死因。尽管 AD 患病率高，目前尚无治疗干预措施来对抗潜在的病理驱动因素 疾病进展。尽管人们对于神经退行性病变的发病机制仍知之甚少， 细胞外淀粉样斑块和细胞内 tau 蛋白缠结的积累是 AD 无可争议的标志。到 对抗疾病进展，一种有吸引力的治疗策略是研究天然蛋白抑制的损伤 用于处理这种神经毒性蛋白质积累的机制。一种这样的机制已被 不仅与 AD 的发生和进展有关，还与许多神经退行性蛋白病有关 包括帕金森病和亨廷顿舞蹈病在内的疾病，是自噬溶酶体网络（ALN）。 ALN 是一种利用囊泡运输来处理大蛋白聚集体的批量降解系统，这有助于 导致神经元功能障碍。该过程依赖于肌动蛋白细胞骨架的主动重塑来启动、捕获、 并运输神经毒性物质进行降解并维持适当的蛋白质稳态。然而，从机制上讲，如何 细胞骨架动力学失调与神经退行性病理学相关，导致 疾病尚不清楚。通过多次行为神经退行性筛查，我们发现了一种肌动蛋白 解聚因子 cofilin 及其上游分子调节剂，经调节后可改善 神经退行性行为缺陷和体内 tau 蛋白积累降低。该提案旨在调查 细胞骨架动力学如何通过以肌动蛋白丝切蛋白为中心的细胞骨架的遗传减弱而导致AD 重塑途径。我假设调节丝切蛋白及其调节剂的活性将改善 AD 神经退行性表型通过细胞骨架和蛋白质稳态的修饰。目标 1 将利用 行为和组织学方法来研究体内众多基因的遗传调节 重塑途径影响 tau 蛋白病果蝇和小鼠模型的神经退行性表型。在 目标 2，我将从机制上研究这种细胞骨架重塑途径如何参与形成 ALN 的进展通过 1) 测量细胞骨架上神经毒性蛋白积累的变化 使用各种 tau 蛋白病模型系统进行遗传调节，以及 2) 利用高分辨率显微镜 AD 患者衍生的诱导多能干细胞 (iPSC) 技术以及生化体外测定， 研究基因调节丝切蛋白如何破坏 ALN 的各个阶段。成功完成后 在这个项目中，我们将识别与细胞骨架重塑相关的分子损伤 与蛋白质稳态失衡和疾病发病机制有关的神经变性。此外，我们 希望在该途径中确定新的治疗靶点，不仅能够治疗 AD，而且能够治疗多种疾病 由神经毒性蛋白积累引起的神经退行性疾病。