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

项目摘要 阿尔茨海默病(AD)是一种进行性与年龄相关的神经退行性疾病，目前是 在美国排在第六位的死亡原因，但目前还没有改变疾病的疗法。 因此，发展以机制为基础的阿尔茨海默病治疗方法势在必行。广告的特点是 病理上由淀粉样β蛋白(Aβ)的存在 全基因组 AS 发布 是 (GMB) 那 这个 vbl.已 假设 ABX介导的 摄动 和 在……里面 通过 绿色荧光蛋白 补语 评量 确定 能 抗生素。 独创性 治疗 腺相关 调整器 炎症性 大脑中的斑块和神经原纤维tau缠绕。近期 协会研究指出神经炎症是Aβ和Tau神经病理的关键驱动因素 以及神经退行性变。反应性星形胶质细胞已被证明对β的生成以及 导致神经退化的有毒物质。然而，星形胶质细胞激活的机制 不是很清楚。最近的研究表明，肠道微生物群中抗生素介导的(ABX)改变 减少小胶质细胞活化，降低脑内A-β斑块负荷。它之前已经展示过了 反应性星形胶质细胞主要由激活的小胶质细胞释放的炎症因子诱导。虽然 小胶质细胞在GMB介导的AD发病机制中的作用已被探讨，而星形胶质细胞的作用尚未见报道 调查过了。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将导致反应性星形胶质细胞诱导排出。 在这个项目中，我建议研究下列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，我将评估抗生素介导的微生物组的影响。 联合共聚焦成像对APPPS1-21(Appps1)小鼠星形胶质细胞形态的研究 Aβ斑块附近胶质纤维酸性蛋白阳性星形胶质细胞的三维重建此外， 目的1、通过星形胶质细胞特异的rna测序，研究星形胶质细胞的转录变化。 将Appps1小鼠与Aldh111EGFP/Rp10 bacTRAP转基因小鼠杂交，获得多倍体下拉 在星形胶质细胞特异性ALDH1L1启动子的控制下与核糖体蛋白L10a融合。我们会 这些数据通过执行单细胞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，我将使用相同的实验方法来 粪便移植(FMT)是否从供体Appps1小鼠回到ABX治疗的Appps1小鼠 将星形胶质细胞表型恢复到用水对照组而不是 在目标3中，我将利用来自目标1和2的转录数据，通过执行基因本体和 通过通路分析确定ABX和FMT对哪些炎症通路的影响最大 并鉴定这些途径的可疑主要转录调控基因。然后我们将设计 携带GFAP启动子的载体转导含有已鉴定主控基因的Appps1小鼠星形胶质细胞 基因，并观察它们是否增加Aβ负荷。敲除这些疑似星形胶质细胞特异性的基因 通路可能代表AD的一种重要治疗策略。 一个 R T S

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