Dysfunctional astroglial exosome to (motor) neuron axon signaling in ALS

ALS 中星形胶质细胞外泌体与（运动）神经元轴突信号传导功能失调

• 批准号: 10364034
• 负责人: Yongjie Yang
• 金额: $ 42.31万
• 依托单位: TUFTS UNIVERSITY BOSTON
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10364034
• 关键词: ALS patients; Adhesions; Affect; Amyotrophic Lateral Sclerosis; Animal Model; Astrocytes; Autopsy; Axon; Biochemical; Brain; Caliber; Cell Adhesion Molecules; Cell Line; Conditioned Culture Media; Data; Dendritic Spines; Disease; Endosomes; Energy Supply; Focal Adhesion Kinase 1; Functional disorder; Growth Cones; Health; Human; Image; Inflammatory; Infusion procedures; Injections; Integrins; Knowledge; Mediating; Methods; Microfluidics; Modeling; Molecular; Molecular Biology; Molecular Motors; Molecular Sieve Chromatography; Morphology; Motor; Motor Neurons; Multivesicular Body; Mus; Mutation; N-Cadherin; Neuraxis; Neurodegenerative Disorders; Neuroglia; Neurons; Outcome; Pathogenesis; Pathology; Pathway interactions; Peripheral Nerves; Pharmacology; Phosphotransferases; Play; Property; Proteins; Proteomics; Reporter; Role; Signal Transduction; Spinal; Spinal Cord; Structure; Testing; Tissue Model; Transgenic Organisms; Ultracentrifugation; Virus; axon growth; axon guidance; axonal degeneration; base; cell type; cytokine; excitotoxicity; exosome; extracellular vesicles; functional loss; induced pluripotent stem cell; loss of function; motor disorder; motor impairment; mouse genetics; mutant; neuronal cell body; neurotransmission; novel; protective effect; protein transport; selective expression; superoxide dismutase 1; synaptogenesis; vesicular release

Abstract Dysfunctions of motor neuron (MN) axons that form both descending motor tracts and peripheral nerve tracts are widely observed in amyotrophic lateral sclerosis (ALS), which often precede MN soma (and axon) degeneration and significantly contribute to disease pathology. Although astroglial adhesion signals are essential for proper axon growth and guidance, whether and how glial adhesion molecules play a role in axon dysfunction/degeneration in ALS remains largely unknown. Although astroglia conditioned medium (ACM) derived from the mouse SOD1 mutant model or from human ALS patient brain astroglia is able to substantially modulate health and survival of MNs, astroglial factors in ACM that modulate MN survival in ALS conditions remain essentially unidentified. Exosomes (50-150 nm in diameter), a major type of secreted extracellular vesicles (EVs), are released from multivesicular bodies (MVBs, an intermediate endosome structure) during endosome maturation. EVs and exosomes secreted from central nervous system (CNS) cell types have emerged as an important intercellular pathway that is implicated in the pathogenesis of neurodegenerative diseases including ALS. How astroglia-derived exosomes affect (motor) neuron survival especially axon properties in ALS remains largely unexplored. In this project, we intend to investigate novel stimulatory and protective roles of astroglial exosomes, especially exosomal adhesion molecule HepaCAM signaling to neurons, in promoting axon growth, functions, and (motor) neuron survival. We will also determine whether dysfunctional HepaCAM signaling from SOD1G93A astroglial exosomes to (motor) neurons contributes to MN axon dysfunction and degeneration in ALS. Based on our preliminary results, we propose the following aims in this project: Aim 1: Determine the effect of astroglial exosomes on (motor) neuron axon growth and functions; Aim 2: Investigate loss-of-function of astroglial exosome signaling to (motor) neurons in ALS models; Aim 3: Elucidate HepaCAM-mediated astroglial exosome signaling to (motor) neurons in ALS models; We have generated a large amount of preliminary data to support our rationales and to demonstrate feasibility for proposed aims. We will employ mouse genetics, primary neuron and astroglial cultures, molecular biology, virus injections, various imaging, and biochemical approaches to complete these aims. Outcomes from this project will reveal a new astroglial exosomal HepaCAM-mediated mechanism in modulating (motor) neuron axon growth and survival. It will also provide important knowledge about the loss-of-functional effect of astroglial exosomes in ALS. These studies will significantly advance our understanding of the astroglial dysfunction in ALS and help develop new astroglia- based neuroprotective strategies.

抽象的 运动神经元（MN）轴突的功能障碍，既形成降落运动区又形成周围神经 在肌萎缩性侧索硬化症（ALS）中广泛观察到，通常在Mn Soma（和Axon）之前 变性并显着促进疾病病理。尽管星形胶质粘附信号是必不可少的 为了适当的轴突生长和指导，神经胶质粘附分子是否在轴突中起作用 ALS中的功能障碍/变性仍然很大未知。尽管星形胶质细胞培养基（ACM） 源自小鼠SOD1突变体模型或人类ALS患者脑星形胶质细胞的能力 调节MN的健康和存活，ACM中的星形胶质因子在ALS条件下调节MN存活 基本上是未识别的。外泌体（直径50-150 nm），一种主要的细胞外类型 囊泡（EV）是从多囊体（MVB，中间内体结构）释放的 内体成熟。已经出现了中枢神经系统（CNS）细胞类型的电动汽车和外泌体 作为与神经退行性疾病的发病机理有关的重要细胞间途径 包括ALS。星形胶质细胞衍生的外泌体如何影响（运动）神经元存活，尤其是ALS中的轴突特性 在很大程度上尚未探索。在这个项目中，我们打算研究新颖的刺激和保护作用 星形胶质细胞外泌体，尤其是外泌体粘附分子Hepacam对神经元的信号传导，以促进轴突 生长，功能和（运动）神经元存活。我们还将确定功能失调的HEPACAM信号传导 从SOD1G93A星形胶质细胞外泌体到（运动）神经元有助于MN轴突功能障碍和变性 在ALS中。 根据我们的初步结果，我们提出了以下目标：目标1：确定 星形胶质外泌体对（运动）神经元轴突生长和功能的影响；目标2：调查功能丧失 ALS模型中的星形胶质外泌体信号转导（运动）神经元； AIM 3：阐明Hepacam介导的 ALS模型中（运动）神经元的星形胶质外部信号传导；我们已经产生了大量 初步数据以支持我们的理由并证明对拟议目标的可行性。我们将雇用 小鼠遗传学，原发性神经元和星形胶质培养物，分子生物学，病毒注射，各种成像和 完成这些目标的生化方法。该项目的结果将揭示一个新的星形胶质 外泌体Hepacam介导的机制调节（运动）神经元轴突生长和存活。它也会 提供有关ALS中星形胶质外泌体的功能丧失作用的重要知识。这些研究 将大大提高我们对ALS中星形胶质功能障碍的理解，并有助于发展新的Astroglia- 基于神经保护策略。