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.

目前有超过30，000名美国人患有肌萎缩侧索硬化症（ALS），其特征在于 由于大脑和脊髓神经细胞的退化， 运动几乎所有的ALS病例最终都是致命的，疾病的快速进展使其 特别是毁灭性的，大多数死亡发生在诊断后2-5年。没有治愈ALS的方法， 仅可用的治疗仅使疾病进展减慢几个月。 更有效和具体的治疗方法，可以阻止甚至逆转神经变性。创新对于这样的 只有更好地理解这些疾病背后的分子和细胞机制， 病理过程。大脑皮层中投射到大脑皮层的“上”运动神经元（UMN）的变性， 脊髓是ALS的重要标志，诊断需要皮质指示。的严重程度 皮质病理学还与疾病进展和预后相关。因为UMN很难 与其他皮质细胞类型不同，它们在临床前研究中经常被忽视。因此，属性 使它们容易受到致病突变的影响， 一直是个谜 这项研究的目的是通过利用尖端的分子、细胞和解剖学技术来克服这一点。 在疾病进展过程中询问UMN神经退行性机制的技术。具体地说，这 该项目将集中在脊髓中UMN轴突的局部病理学。这些纤维的丢失是早期的 ALS的现象，其特征在于皮质脊髓束（CST）的变薄和瘢痕形成， 疾病发作的触发因素。在早期时间点也观察到CST轴突的凋亡 在临床前动物模型中，通常在UMN丧失之前。这项拨款将利用一个常见的ALS小鼠模型 利用SOD 1基因（SOD 1G 93 A）中的疾病相关突变， 在人类患者身上看到的。在目标1中，先进的病毒追踪技术将用于标记神经元中的神经元。 小鼠脊髓接受来自UMN直接突触输入，并在疾病期间映射连接变化 进展同时，翻译核糖体亲和纯化（TRAP）方法将用于目标2， 监测轴突中局部表达的基因的变化。目标3将检查生物能量 轴突的性质，通过采用一种新的方法来分离轴突线粒体，以执行 在疾病进展期间进行生化和代谢分析。这项探索性研究将是第一个直接 因此，在变性轴突中，将解剖学、基因表达和生物能量学的变化相关联， 为进一步研究CST的病理机制奠定了基础。