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。

基本信息

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
项目类别：
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

项目摘要

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)，其特征是由于控制大脑和脊髓的神经细胞退化而导致进行性瘫痪几乎所有 ALS 病例最终都是致命的，而且疾病的快速进展使其死亡。尤其具有破坏性，大多数死亡发生在诊断后 2-5 年内。 ALS 和 ALS 尚无治愈方法。现有的治疗方法只能将疾病进展减缓几个月，因此，非常需要可以阻止甚至逆转神经退行性疾病的更有效和具体的疗法。只有更好地了解其背后的分子和细胞机制，才能产生治疗方法大脑皮层中投射到的“上”运动神经元（UMN）的退化。脊髓是 ALS 的重要标志，诊断时需要皮质指征。皮质病理学也与疾病进展和预后相关，因为 UMN 很难确定。与其他皮质细胞类型的区别，它们在临床前研究中经常被忽视，因此，其特性。这使得它们容易受到致病突变及其退化机制的影响一直是个谜。拟议的研究旨在通过利用尖端的分子、细胞和解剖学来克服这一问题具体来说，是研究疾病进展过程中 UMN 神经退行性机制的技术。该项目将重点研究脊髓 UMN 轴突的局部病理学，这些纤维的损失是早期的。 ALS 现象，其特征是皮质脊髓束 (CST) 变薄和形成疤痕，可能是在早期时间点也观察到了 CST 轴突的异常。在临床前动物模型中，通常在 UMN 丧失之前，这项资助将利用常见的 ALS 小鼠模型。利用 SOD1 基因 (SOD1G93A) 中与疾病相关的突变并概括神经退行性变在目标 1 中，先进的病毒追踪技术将用于标记神经元。小鼠脊髓接收来自 UMN 的直接突触输入并绘制疾病期间连接性的变化与此同时，目标 2 中将使用翻译核糖体亲和纯化 (TRAP) 方法监测轴突局部表达基因的变化，目标 3 将检查生物能。通过采用一种新方法分离轴突线粒体来研究轴突的特性这项探索性研究将是第一个直接对疾病进展过程进行生化和代谢分析的研究。关联解剖学、基因表达和生物能量学的变化，特别是在退化轴突中，因此为今后研究 CST 病理机制的工作奠定基础。