Using mitochondrial Ca2+ uptake as a therapeutic target for ALS

使用线粒体 Ca2 摄取作为 ALS 的治疗靶点

基本信息

批准号：
10659923
负责人：
Lan Wei-LaPierre
金额：
$ 48万
依托单位：
UNIVERSITY OF FLORIDA
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：
2023-05-01 至 2027-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10659923
关键词：
ALS pathology ALS patients Adult Alleles Amyotrophic Lateral Sclerosis Animals Attenuated Axon Bioenergetics Brain Buffers C9ORF72 Cell Death Cell Membrane Permeability Cuprozinc Superoxide Dismutase DNA-Binding Proteins Defect Degenerative Disorder Disease Disease Progression Dissection Distal Dominant-Negative Mutation Electron Microscopy Event Exercise Generations Genes Genetic Genetic Models Homeostasis Immunohistochemistry In Situ Longevity Measurement Membrane Potentials Mitochondria Molecular Motor Motor Neurons Mus Muscle Muscle Contraction Muscle Fibers Muscle denervation procedure Muscle function Mutation Neurodegenerative Disorders Neuromuscular Junction Onset of illness Outcome Paralysed Pathogenesis Pathologic Pathology Patients Performance Phenotype Property Reporting Research Respiratory Chain Respiratory Failure Role Signal Transduction Skeletal Muscle Soleus Muscle Spinal Cord Structure Symptoms System Testing Therapeutic Effect Tissues Transgenic Mice Treatment Efficacy Western Blotting amyotrophic lateral sclerosis therapy attenuation axonopathy behavioral study effective therapy extensor digitorum improved in vivo mitochondrial dysfunction mitochondrial membrane mouse model muscular structure neuron loss neuronal survival new therapeutic target postsynaptic pre-clinical preservation presynaptic prevent therapeutic target uptake

项目摘要

Amyotrophic lateral sclerosis (ALS) is a fatal, adult-onset neurodegenerative disease characterized by progressive motor neuron (MN) loss, muscle denervation, and eventually, paralysis. Currently, no effective treatments are available to stop or reverse ALS disease progression and the precise molecular mechanisms underlie ALS pathogenesis remain elusive. Prior studies revealed decreased mitochondrial respiratory chain activity, altered mitochondrial ultrastructure, and mitochondrial dysfunction in both MN and skeletal muscle (SM) in ALS patients and mouse models. The first sign of ALS pathology occurs at the neuromuscular junction (NMJ), where presynaptic MN axons connect with postsynaptic SM end plates. To date, whether signals resulting in the initial NMJ damage are from MN or SM remain unclear. In this project, we aim to determine the tissue-specific causative role of mitochondrial Ca2+ uptake in SM and MN in disease onset and progression, and the therapeutic efficacy of reducing mitochondrial Ca2+ uptake on NMJ and SM function in ALS mice. We hypothesize that mitochondrial Ca2+ mishandling in both SM and MN actively contribute to ALS disease pathogenesis and that attenuating mitochondrial Ca2+ uptake mitigates mitochondrial damage and preserves NMJ/muscle function. To test this hypothesis, we will use transgenic mice with inducible, SM or MN-specific expression of a dominant negative form of the mitochondrial Ca2+ uniporter to specifically and selectively reduce mitochondrial Ca2+ uptake in SM and MN in hSOD1G93A mice and C9-500 (C9orf72) mice, two mouse models associated with the most prevalent genetic causes for ALS. The central hypothesis will be tested in two Specific Aims. Aim 1 will determine the role of mitochondrial Ca2+ uptake in SM or MN in survival, motor function, NMJ function and in vivo muscle performance in hSOD1G93A and C9-500 mice. Aim 2 will assess the impact of tissue-specific inhibition of mitochondrial Ca2+ uptake in SM or MN on NMJ and muscle structure, MN survival, muscle intrinsic contractile properties, mitochondrial structure and mitochondrial bioenergetics in SM of hSOD1G93A and C9-500 mice. This project will: 1) provide a systematic, longitudinal characterization of SM and NMJ function from a cellular level to whole animal level at different stages of disease progression in hSOD1G93A and C9-500 mice; 2) determine the degrees to which defects in mitochondrial Ca2+ uptake in SM or MN contribute to altered NMJ structure/function, disease onset and progression in hSOD1G93A and C9-500 mice; 3) provide the first detailed dissection on the relative role of mitochondrial Ca2+ uptake in SM and MN in ALS phenotype using the same genetic models and determine the origin of the signals that result in NMJ destruction (from SM or MN or both); 4) provide mechanistic evidence for whether mitochondrial Ca2+ mishandling is a trigger or a target for disease progression in ALS mice, regardless of the causing mutations (mitochondrial related or non-mitochondrial related); and most importantly, 5) test the validity of a potential new therapeutic target (mitochondrial Ca2+ uptake, or the mitochondrial Ca2+ uniporter) for the treatment of ALS.

肌萎缩性外侧硬化症（ALS）是一种致命的成人神经退行性疾病，其特征是进行性运动神经元（MN）损失，肌肉神经保护，最终是瘫痪。目前，无效可以治疗可停止或逆转ALS疾病进展和精确的分子机制基础ALS发病机理仍然难以捉摸。先前的研究表明，线粒体呼吸链下降 MN和骨骼肌的活性，线粒体超微结构和线粒体功能障碍（SM）在ALS患者和小鼠模型中。 ALS病理学的第一个迹象发生在神经肌肉连接（NMJ），突触前的MN轴突与突触后SM端板相连。迄今为止，是否发出信号导致最初的NMJ损坏来自MN或SM尚不清楚。在这个项目中，我们旨在确定组织特异性线粒体Ca2+摄取在SM和MN疾病发作和进展中的病因作用以及治疗性在ALS小鼠中减少NMJ和SM功能的线粒体Ca2+摄取的功效。我们假设这一点线粒体Ca2+ SM和MN中的不当行为会积极促进ALS疾病发病机理，并且衰减线粒体Ca2+摄取可减轻线粒体损伤并保留NMJ/肌肉功能。到检验该假设，我们将使用具有诱导性，SM或MN特异性表达的转基因小鼠线粒体Ca2+ Uniporter的负面形式，并有选择地减少线粒体Ca2+摄取在HSOD1G93A小鼠和C9-500（C9ORF72）小鼠中的SM和MN中，两种与最多相关的鼠标模型 ALS的普遍遗传原因。中心假设将以两个具体的目的进行检验。 AIM 1将确定线粒体Ca2+摄取在SM或MN中的作用在生存，运动功能，NMJ功能和体内肌肉中的作用 HSOD1G93A和C9-500小鼠的性能。 AIM 2将评估组织特异性抑制的影响 NMJ和肌肉结构中的SM或MN中的线粒体Ca2+摄取，MN存活，肌肉内在收缩在HSOD1G93A和C9-500小鼠的SM中的特性，线粒体结构和线粒体生物能学。这项目将：1）从细胞水平到SM和NMJ功能的系统，纵向表征 HSOD1G93A和C9-500小鼠的疾病进展不同阶段的整个动物水平； 2）确定 SM或MN中线粒体Ca2+摄取中缺陷的学位有助于改变NMJ的结构/功能， HSOD1G93A和C9-500小鼠的疾病发作和进展； 3）在使用相同的遗传模型和确定导致NMJ破坏的信号的起源（来自SM或MN或两者）； 4）提供机械线粒体Ca2+不当行为是ALS小鼠的疾病进展的触发因素还是靶标的证据。不管引起突变（线粒体相关或非用线方面相关）不管）；最重要的是， 5）测试潜在的新治疗靶标的有效性（线粒体Ca2+摄取或线粒体Ca2+ Uniporter）用于治疗ALS。