The gut microbiome in Alzheimer's disease: exploring the role of astrocytes

阿尔茨海默病中的肠道微生物组：探索星形胶质细胞的作用

• 批准号: 10737613
• 负责人: Sidhanth Chandra
• 金额: $ 5.27万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10737613
• 关键词: 3-Dimensional; Affect; Alzheimer' s Disease; Alzheimer' s disease model; Alzheimer' s disease pathology; Alzheimer' s disease therapeutic; Amyloid beta-Protein; Animal Model; Antibiotics; Astrocytes; Back; Bacteria; Brain; Candidate Disease Gene; Cause of Death; Cell Separation; Complement; Complement 1q; Data; Dementia; Dependovirus; Deposition; Development; Disease; Donor person; Elderly; Etiology; Future; Gene Expression Profile; Generations; Genes; Genetic Transcription; Glial Fibrillary Acidic Protein; Gliosis; Heterogeneity; Human; Image; Inflammatory; Interleukins; Intestines; Mediating; Methods; Microglia; Modeling; Morphology; Mus; Natural Immunity; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Ontology; Pathogenesis; Pathologic; Pathology; Pathway Analysis; Pathway interactions; Phenotype; Poison; Polyribosomes; Publishing; RNA; Regulator Genes; Research; Ribosomal Proteins; Role; Satellite Viruses; Senile Plaques; TNF gene; Tauopathies; Technology; Therapeutic; Transgenic Mice; Transplantation; United States; Water; abeta deposition; age related neurodegeneration; astrogliosis; candidate selection; confocal imaging; design; experimental study; genetic risk factor; genome wide association study; genome-wide; glial activation; gut microbiome; innovation; insight; knock-down; male; microbiome; microbiome alteration; mouse model; neuroinflammation; neurotoxic; novel; overexpression; promoter; reconstruction; release factor; response; single-cell RNA sequencing; tau aggregation; therapeutic target; transcriptome; transcriptome sequencing; transcriptomics; vector

Project Summary Alzheimer's disease (AD) is a progressive age-related neurodegenerative disorder which is currently the 6th leading cause of death in the United States, but there are currently no disease-modifying therapeutics. Therefore, the development of mechanism-based therapeutics for AD is imperative. AD is characterized pathologically by the presence of amyloid beta (Aβ) genome-wide as release are (GMB) that the been hypothesize abx-mediated perturbation and in via eGFP complement assess determine can antibiotics. ingenuity treatment adeno-associated regulator inflammatory plaques nd neurofibrillary tau tangles i n the brain. Recent association studies point to neuroinflammation as a critical driver of Aβ and tau neuropathology well as neurodegeneration. Reactive astrocytes have been shown to contribute to Aβ generation as well as toxic substances that cause neurodegeneration. However, mechanisms governing astrocyte activation not well understood. Recent studies indicate that antibiotic-mediated (abx) alterations in the gut microbiome decrease microglial activation and decrease Aβ plaque load in the brain. It has previously been shown reactive astrocytes are induced primarily by inflammatory factors released f rom activated microglia. Although role of microglia has been explored in GMB mediated AD pathogenesis, the role of astrocytes has not yet investigated. Because of the previously established connection between microglia and astrocytes, we that abx will cause a eduction in reactive astrocyte induction. In this project, I propose to investigate morphological and transcriptional changes in astrocytes following microbiome perturbation. In Aim 1, I will assess the impac of antibiotic-mediated microbiome on astrocyte morphology in APPPS1-21 (Appps1) mice using a combination of confocal imaging 3D-reconstruction of glial fibrillary acidic protein ( Gfap ) positive astrocytes near Aβ plaques. Furthermore, Aim 1, I will tudy the transcriptional changes in astrocytes, by performing astrocyte-specific RNA sequencing polysomal pull down by crossing Appps1 mice to the Aldh1l1EGFP/Rpl10 bacTRAP transgenic mice, i n which is fused to ribosomal protein L10a under the control of the astrocyte-specific aldh1l1 promoter. We will these data by performing single-cell RNA sequencing transcriptomics experiments where we can astrocyte transcriptional heterogeneity. In Aim 2, I will utilize the same experimental approaches to whether fecal matter transplant (FMT) from donor Appps1 mice back into abx-treated Appps1 mice restore astrocyte phenotypes to those seen in Appps1 mice that were treated with water control instead of In Aim 3, I will leverage transcriptional data from Aims 1 and 2 by performing gene ontology and pathway analysis to determine which inflammatory pathways were the most altered by abx and FMT and identify suspected master transcriptional regulator genes of these pathways. We will then design vectors with Gfap promoter to transduce astrocytes in Appps1 mice with the identified master genes and observe whether they increase Aβ load. Knockdown of these suspected astrocyte-specific pathways could represent an important therapeutic strategy for AD. a r t s

项目摘要 阿尔茨海默病（Alzheimer's disease，AD）是一种进行性的年龄相关性神经退行性疾病， 在美国是第六大死亡原因，但目前还没有改善疾病的治疗方法。 因此，开发基于机制的AD治疗药物势在必行。AD的特征 在病理学上是由于β淀粉样蛋白（Aβ）的存在 全基因 作为 释放 是 （专线小巴） 的 的 被 假设 abx介导 摄动 和 在 经由 EGFP 补充 评估 确定 可以 抗生素 匠心 治疗 腺相关 调节器 炎性 大脑中的斑块和神经元性tau蛋白缠结。最近 相关研究指出，神经炎症是Aβ和tau神经病理学的关键驱动因素 以及神经退化。反应性星形胶质细胞已被证明有助于Aβ的产生， 导致神经退化的有毒物质然而，控制星形胶质细胞活化的机制 没有被很好地理解。最近的研究表明，肠道微生物组中的抗生素介导的（abx）改变 减少小胶质细胞活化和减少脑中Aβ斑块负荷。之前已经证明 反应性星形胶质细胞主要由活化的小胶质细胞释放的炎性因子诱导。虽然 小胶质细胞在GMB介导的AD发病机制中的作用已经被探索，星形胶质细胞的作用还没有 研究了由于先前建立的小胶质细胞和星形胶质细胞之间的联系，我们 ABX会导致反应性星形胶质细胞诱导的减少。 在这个项目中，我建议研究星形胶质细胞的形态和转录变化， 微生物群扰动在目标1中，我将评估寄生虫介导的微生物组的影响， APPPS 1 -21（Appps 1）小鼠星形胶质细胞形态学的研究 Aβ斑块附近胶质细胞酸性蛋白（GFAP）阳性星形胶质细胞的三维重建。此外，委员会认为， 目的1、通过对星形胶质细胞特异性RNA测序，研究星形胶质细胞转录水平的变化 通过将Appps 1小鼠与Aldh 111 EGFP/Rp 110 bacTRAP转基因小鼠杂交， 在星形胶质细胞特异性aldh 1 l1启动子的控制下与核糖体蛋白L10 a融合。我们将 通过进行单细胞RNA测序转录组学实验，我们可以 星形胶质细胞转录异质性。在目标2中，我将利用相同的实验方法， 是否将来自供体Appps 1小鼠的粪便移植（FMT）回输给abx处理的Appps 1小鼠 将星形胶质细胞表型恢复到用水对照而不是 在目标3中，我将利用目标1和2的转录数据， 通路分析，以确定哪些炎症通路被abx和FMT改变最多 并鉴定这些途径的疑似主转录调节基因。我们将设计 将具有Gfap启动子的载体转染至具有鉴定的主基因的Appps 1小鼠中的星形胶质细胞 基因，并观察它们是否增加Aβ负荷。敲除这些可疑的星形胶质细胞特异性 通路可能代表AD的重要治疗策略。 一 R 不 S