Phenotyping Corticospinal Axon Degeneration in Preclinical ALS Models.

临床前 ALS 模型中皮质脊髓轴突变性的表型分析。

• 批准号: 10732637
• 负责人: Eric F Schmidt
• 金额: $ 46.61万
• 依托单位: ROCKEFELLER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10732637
• 关键词: ALS patients; Affinity Chromatography; American; Amyotrophic Lateral Sclerosis; Anatomy; Animal Model; Atrophic; Axon; Axonal Transport; Binding; Biochemical; Bioenergetics; Bioinformatics; Brain; Brain Stem; Cell Death; Cell physiology; Cells; Cerebral cortex; Cessation of life; Chromosome Mapping; Cicatrix; Clinical; Cortical Cord; Corticospinal Tracts; Data; Dendrites; Dependovirus; Detection; Diagnosis; Disease; Disease Progression; Disease model; Fiber; Foundations; Functional disorder; Future; Gene Expression; Genes; Genetic; Grant; Histologic; Human; Knowledge; Label; Link; Maps; Measures; Mediating; Messenger RNA; Metabolic; Methods; Mitochondria; Modeling; Molecular; Monitor; Motor Cortex; Motor Neuron Disease; Motor Neurons; Movement; Mus; Mutation; Nerve Degeneration; Neurons; Onset of illness; Paralysed; Pathologic Processes; Pathology; Pathway interactions; Patients; Phenotype; Polyribosomes; Population; Pre-Clinical Model; Presynaptic Terminals; Property; Proteomics; Pyramidal Cells; RNA purification; Reporter; Reproducibility; Research; Ribosomal Proteins; Ribosomes; Role; Severities; Spinal; Spinal Cord; Structure; Synapses; Techniques; Therapeutic; Thinness; Time; Transcript; Translating; Vertebral column; Viral; Viral Vector; Work; axonal degeneration; cell cortex; cell type; differential expression; disease prognosis; disease-causing mutation; excitotoxicity; experimental study; gene repression; in vivo; innovation; motor symptom; mouse model; neuron loss; neuronal cell body; novel; novel strategies; postsynaptic; pre-clinical; preclinical study; superoxide dismutase 1; synaptic function; transcriptome sequencing

Over 30,000 Americans currently suffer from amyotrophic lateral sclerosis (ALS) which is characterized by progressive paralysis due to the degeneration of nerve cells in the brain and spinal cord that control movement. Almost all cases of ALS are eventually fatal, and the rapid progression of the disease makes it particularly devastating, with most deaths occurring 2-5 years from diagnosis. No cure exists for ALS and the only available treatments slow disease progression by merely a few months Therefore, a great need exists for more effective and specific therapies that can stop or even reverse neurodegeneration. Innovation for such therapies will only arise from a better understanding of the molecular and cellular mechanisms underlying the pathological process. Degeneration of the “upper” motor neurons (UMNs) in the cerebral cortex that project to the spinal cord is an important hallmark of ALS and a cortical indication is required for diagnosis. The severity of cortical pathology also correlates with disease progression and prognosis. Because UMNs are difficult to distinguish from other cortical cell types they are often overlooked in preclinical studies. Therefore, properties that make them vulnerable to disease-causing mutations and the mechanisms that underlie their degeneration have remained a mystery. The proposed study aims to overcome this by utilizing cutting edge molecular, cellular, and anatomical techniques to interrogate neurodegenerative mechanisms in UMNs during disease progression. Specifically, this project will focus on the local pathology of the axons of UMNs in the spinal cord. Loss of these fibers is an early phenomenon of ALS and is characterized by a thinning and scarring of the corticospinal tract (CST) and may be a triggering factor for disease onset. Abnormalities in CST axons have also been observed at early time points in preclinical animal models, often preceding UMN loss. This grant will utilize a common mouse model of ALS that utilizes disease-linked mutations in the SOD1 gene (SOD1G93A) and recapitulates the neurodegeneration seen in human patients. In Aim 1, advanced viral tracing techniques will be used to label the neurons in the mouse spinal cord that receive direct synaptic input from UMNs and map changes in connectivity during disease progression. In parallel, the translating ribosome affinity purification (TRAP) method will be used in Aim 2 to monitor changes in the genes that are locally expressed in the axons. Aim 3 will examine the bioenergetic properties of the axons by employing a novel approach to isolate axonal mitochondria in order to perform biochemical and metabolic analyses during disease progression. This exploratory study will be the first to directly correlate changes in anatomy, gene expression, and bioenergetics specifically in degenerating axons, therefore laying a foundation for future work investigating mechanisms of CST pathology.

目前有30,000多名美国人患有肌萎缩性侧索硬化症（ALS），其特征是 通过进行性麻痹，由于大脑和脊髓中神经细胞的变性而导致 移动。几乎所有ALS病例有时都是致命的，疾病的快速发展使得 特别是毁灭性的，大多数死亡发生在诊断后2 - 5年。 ALS和 仅几个月就只有可用的治疗缓慢的疾病进展，因此存在很大的需求 可以停止甚至逆转神经变性的更有效和特定的疗法。创新 疗法只会由对分子和细胞机制的更好理解产生 病理过程。在大脑皮层中“上部”运动神经元（UMNS）的变性 脊髓是ALS的重要标志，诊断需要皮质指示。严重性 皮质病理学还与疾病的进展和预后相关。因为umns很难 在临床前研究中，它们与其他皮质细胞类型的区别。因此，属性 这使它们容易受到引起疾病的突变的影响以及其退化的基础的机制 仍然是一个谜。 拟议的研究旨在通过使用尖端分子，细胞和解剖学来克服这一点 在疾病进展过程中询问UMN中神经退行性机制的技术。具体来说，这是 项目将集中在脊髓中UMNS轴突的局部病理上。这些纤维的损失是早期的 ALS的现象，其特征是皮质脊髓区（CST）的变薄和疤痕，可能是 疾病发作的触发因素。在早期点也观察到CST轴突异常 在临床前动物模型中，通常是在UMN损失之前。该赠款将利用ALS的常见鼠标模型 在SOD1基因（SOD1G93A）中使用疾病连接的突变并概括了神经变性 参见人类患者。在AIM 1中，高级病毒追踪技术将用于标记神经元 小鼠脊髓从UMNS接收直接突触输入并在疾病期间的连通性变化 进展。同时，将在AIM 2中使用翻译核糖体亲和力纯化（TRAP）方法 监视轴突中局部表达的基因的变化。 AIM 3将检查生物能量 轴突的性质通过采用新型方法来分离轴突线粒体以进行 疾病进展过程中的生化和代谢分析。这项探索性研究将是第一个直接的 相关的解剖学，基因表达和生物能的变化专门在退化轴突中，因此 为未来的工作调查CST病理学机制奠定基础。