Exploring CRMP5 as a novel target for Alzheimers disease

探索 CRMP5 作为阿尔茨海默病的新靶点

基本信息

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
项目类别：
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&apos s Disease Alzheimer&apos s disease brain Alzheimer&apos s disease model Alzheimer&apos 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

项目摘要

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.

抽象的阿尔茨海默病（AD）是一种毁灭性的疾病，给人们带来巨大的情感和社会经济负担。由于我们社会人口老龄化，患阿尔茨海默病的风险不断增加以及缺乏适当的疾病缓解策略，AD 现在被视为全球性的紧迫危机。在本提案中，我们建议。新的治疗靶点：塌陷反应介导蛋白 (CRMP)-5，一种微管蛋白聚合抑制剂这里的基本原理是针对限制神经元连接的蛋白质。海马体是 AD 中神经元丢失的主要区域，可能被证明是减轻 AD 神经毒性的有效策略在海马体中，CRMP5 与正在生长的轴突中的微管蛋白相互作用，从而阻止其生长。在 AD 患者的大脑中，CRMP5 的表达增加。本补充材料基于 (i) CRMP5 的观察。 AD 3xTg 小鼠模型中的表达增加，(ii) CRMP5 表达增加减少 3xTg-AD 小鼠的社交能力，(iii) CRMP5 敲除挽救了 3xTg-AD 小鼠的社交表现，(iv) CRMP5 增加线粒体碎片，从而参与 AD 中已知的线粒体功能障碍大脑，(v) CRMP5 控制 GluN2B 的突触后表达，GluN2B 是一种与 AD 诱导相关的离子通道这些结果表明CRMP5上调是参与AD的病理特征。然而，CRMP5 在 AD 发病机制中的作用仍然未知，在本补充材料中，我们将进行讨论。测试 CRMP5 敲除对记忆障碍、社交退缩以及神经功能的影响为此，我们将培育一种过度表达人类淀粉样蛋白前体的 J20 小鼠品系。具有与家族性 AD 相关的两个突变（瑞典突变和印第安纳突变）的蛋白质 (APP)，以及我们目前的 CRMP5 我们将通过评估 J20–crmp5-/- 和 J20–crmp5wt 小鼠的认知行为来比较它们。使用新颖的物体识别和莫里斯水迷宫测试及其使用三室的社会行为我们将评估 Aβ 负荷以及海马体和前额皮质的突触完整性。我们还将使用坏死性凋亡标记物通过免疫印迹评估神经元损失，从而导致细胞死亡在人类和 AD 小鼠模型中，线粒体功能障碍（AD 病理生理学的潜在机制）将被证实。我们使用电生理学通过细胞生物能量分析和线粒体中的 Aβ 负荷进行评估。将通过测量海马和前额皮质的长时程增强 (LTP) 来测试突触功能我们预计 J20 小鼠中 CRMP5 的敲低将导致 AD 表型减少。通过（i）增加记忆力和社会行为，（ii）减少淀粉样斑块负担，（iii）改善线粒体功能，（iv）减少神经元死亡，以及（v）增强突触完整性和功能。响应 NOT-AG-22-025 的行政补充请求将有助于启动更大、更多的评估 CRMP5 减轻 AD 症状负担的综合研究。