Exploring CRMP5 as a novel target for Alzheimers disease

探索 CRMP5 作为阿尔茨海默病的新靶点

• 批准号: 10712329
• 负责人: Liberty Francois Ep Moutal
• 金额: $ 37.77万
• 依托单位: SAINT LOUIS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-14 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10712329
• 关键词: 3xTg-AD mouse; Acceleration; Administrative Supplement; Adult; Affect; Age; Alzheimer' s Disease; Alzheimer' s disease brain; Alzheimer' s disease model; Alzheimer' s disease patient; Amyloid deposition; Autoantibodies; Autopsy; Awareness; Axon; Behavior; Behavioral; Behavioral Symptoms; Biochemical; Biochemistry; Bioenergetics; Biology; Brain; Breeding; Cause of Death; Cell Death; Cognitive; Data; Dementia; Disease; Down-Regulation; Economic Burden; Electrophysiology (science); Emotional; Functional disorder; Funding; Generations; Grant; Growth; Health; Hippocampus; Human; Human Amyloid Precursor Protein; Immunohistochemistry; Investments; Ion Channel; J20 mouse; Knock-out; Link; Long-Term Potentiation; Measures; Mediator; Medicine; Memory; Memory impairment; Mitochondria; Mus; Mutation; N-Methyl-D-Aspartate Receptors; Nerve Degeneration; Neurites; Neurofibrillary Tangles; Neurons; Pathogenesis; Pathologic; Patients; Peptides; Performance; Population; Positioning Attribute; Postsynaptic Membrane; Prefrontal Cortex; Prevalence; Protein Isoforms; Proteins; Research; Risk; Role; Semaphorin-3A; Senile Plaques; Signal Transduction; Slice; Social Behavior; Socialization; Societies; Symptoms; Synapses; Testing; Tissues; Transgenic Organisms; Tubulin; United States; Up-Regulation; V717F; Western Blotting; Withdrawal; age related; aging population; cohort; dentate gyrus; disease phenotype; familial Alzheimer disease; hyperphosphorylated tau; improved; knock-down; mitochondrial dysfunction; morris water maze; mouse model; neurogenesis; neuron loss; neurotoxicity; new therapeutic target; novel; object recognition; olfactory bulb; overexpression; painful neuropathy; postsynaptic; preclinical study; programs; protein protein interaction; response; social; socioeconomics; transcriptome sequencing; tubulin polymerization inhibitor; β-amyloid burden

ABSTRACT Alzheimer’s disease (AD) is a devastating disease that bears a huge emotional and socio-economic burden. Because of the aging population of our societies, the increasing risks of developing Alzheimer and the lack of proper disease-mitigating strategy, AD is now viewed as a global and urgent crisis. In this proposal, we suggest a new therapeutic target: Collapsin Response Mediator Protein (CRMP)-5, an inhibitor of tubulin polymerization and neurite outgrowth. The rationale here is that targeting proteins that restrict neuronal connectivity of the hippocampus, a prime region of neuronal loss in AD, could prove a valid strategy to mitigate neurotoxicity in AD and decrease its burden. In the hippocampus CRMP5 interacts with tubulin in the growing axon thus halting its growth and negatively regulates neurogenesis. In brains from AD patients, CRMP5 expression is increased in the hippocampus and in the pre-frontal cortex. This supplement builds on the observations that (i) CRMP5 expression was increased in the 3xTg mouse model of AD, (ii) increased CRMP5 expression reduced socialization in 3xTg-AD mice, (iii) CRMP5 knockdown rescued social performance in 3xTg-AD mice, (iv) CRMP5 increases mitochondrial fragmentation, thereby participating in the known dysfunction of mitochondria in the AD brain, (v) CRMP5 controls the post-synaptic expression of GluN2B, an ion channel implicated in AD-induced memory impairment. These results show that CRMP5 upregulation is a pathological feature participating to AD however the function for CRMP5 in the pathogenesis of AD remains unknown. Within this supplement, we will test the effect of CRMP5 knockout on memory impairment and social withdrawal as well as neuronal function in a mouse model of AD. To do so, we will breed a J20 mouse line, which overexpresses human amyloid precursor protein (APP) with two mutations (Swedish and Indiana mutations) linked to familial AD, with our current CRMP5 KO line. We will compare our J20–crmp5-/-compared to J20–crmp5wt mice by evaluating their cognitive behaviors using the novel object recognition and Morris water maze tests and their social behavior using the three-chamber paradigm test. We will assess Aβ burden, as well as synaptic integrity in the hippocampus and pre-frontal cortex. We will also evaluate neuronal loss by immunoblotting using markers of necroptosis, contributing to cell death in human and AD mice models. Mitochondrial dysfunction, an underlying mechanism of AD pathophysiology, will be assessed by cellular bioenergetic profiling and Aβ burden in the mitochondria. Using electrophysiology, we will test synaptic functionality by measuring long-term potentiation (LTP) in hippocampal and prefrontal cortex slices. We expect that knock-down of CRMP5 in the J20 mouse will result in reduced AD phenotypes, defined by (i) increasing memory and social behaviors, (ii) decreasing amyloid plaques burden, (iii) improving mitochondria function, (iv) decreasing neuronal death, and (v) enhancing synaptic integrity and function. This Administrative Supplement request in response to NOT-AG-22-025 will help kickstart a larger and more comprehensive study to evaluate the targeting of CRMP5 to decrease the burden of AD symptoms.

摘要 阿尔茨海默氏病（AD）是一种毁灭性的疾病，其承受巨大的情感和社会经济负担。 由于我们社会的人口老龄化，患阿尔茨海默病的风险增加，缺乏 由于缺乏适当的疾病缓解策略，AD现在被视为全球性的紧急危机。在本提案中，我们建议 一种新的治疗靶点：微管蛋白聚合抑制剂Collapsin Response Mediator Protein（CRMP）-5 和神经突生长这里的基本原理是，靶向限制神经元连接的蛋白质， 海马是AD中神经元丢失的主要区域，可以证明是减轻AD神经毒性的有效策略 减轻它的负担。在海马体中，CRMP 5与生长轴突中的微管蛋白相互作用，从而阻止其生长。 生长和负调节神经发生。在AD患者的大脑中，CRMP 5表达在AD患者中增加。 海马体和前额叶皮层。本补编的基础是以下意见： 在AD的3xTg小鼠模型中表达增加，（ii）CRMP 5表达增加降低 在3xTg-AD小鼠中的社会化，（iii）CRMP 5敲低挽救了3xTg-AD小鼠中的社会表现，（iv）CRMP 5敲低挽救了3xTg-AD小鼠中的社会表现。 增加线粒体断裂，从而参与AD中线粒体的已知功能障碍 （v）CRMP 5控制GluN 2B的突触后表达，GluN 2B是一种与AD诱导的神经元凋亡有关的离子通道。 记忆受损这些结果表明，CRMP 5上调是参与AD的病理特征 然而，CRMP 5在AD发病机制中的功能仍不清楚。在此补充中，我们将 测试CRMP 5敲除对记忆障碍和社交退缩以及神经元功能的影响， AD的小鼠模型。为此，我们将培育一个J20小鼠系，它过度表达人类淀粉样蛋白前体 与家族性AD相关的两个突变（瑞典和印第安纳州突变）的蛋白质（APP），我们目前的CRMP 5 KO线。我们将通过评估J20-crmp 5-/-小鼠和J20-crmp 5 wt小鼠的认知行为来比较它们 使用新的物体识别和莫里斯水迷宫测试和他们的社会行为，使用三腔室 范式检验我们将评估Aβ负荷，以及海马和前额叶皮层中的突触完整性。 我们还将使用坏死性凋亡的标记物通过免疫印迹评估神经元损失，从而促进细胞死亡 在人类和AD小鼠模型中。线粒体功能障碍是AD病理生理学的潜在机制， 通过细胞生物能谱和线粒体中的Aβ负荷进行评估。利用电生理学，我们 将通过测量海马和前额叶皮层的长时程增强（LTP）来测试突触功能 切片我们预计J20小鼠中CRMP 5的敲低将导致AD表型减少，定义如下 通过（i）增加记忆和社会行为，（ii）减少淀粉样蛋白斑块负担，（iii）改善 线粒体功能，（iv）减少神经元死亡，和（v）增强突触完整性和功能。这 响应NOT-AG-22-025的行政补充请求将有助于启动一个更大、更 评估CRMP 5靶向降低AD症状负担的综合研究。