Development of in vivo quantitative stable isotope probing to quantify microbiome dynamics in Alzheimers Disease

开发体内定量稳定同位素探测以量化阿尔茨海默病微生物组动态

• 批准号: 10473765
• 负责人: Emily K Cope
• 金额: $ 19万
• 依托单位: NORTHERN ARIZONA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10473765
• 关键词: 16S ribosomal RNA sequencing; 3xTg-AD mouse; AD transgenic mice; Address; Aging; Alzheimer' s Disease; Alzheimer' s disease model; Alzheimer' s disease pathology; Alzheimer' s disease risk; Amyloid; Amyloid beta-Protein; Amyloidosis; Bacteria; Blood - brain barrier anatomy; Brain; Cardiovascular system; Cessation of life; Communities; DNA; DNA sequencing; Data; Death Rate; Dementia; Density Gradient Centrifugation; Deposition; Development; Disease Progression; Ecology; Ecosystem; Elderly; Enteric Nervous System; Etiology; Exhibits; Gastrointestinal tract structure; Goals; Growth; Health; Human; Human Microbiome; Human body; Immune; Immune system; Individual; Inflammatory; Isotope Labeling; Isotopes; Label; Longitudinal Studies; Measures; Methods; Microbe; Mouse Strains; Mus; Nature; Nerve Degeneration; Neurofibrillary Tangles; Neurologic; Neurotransmitters; Nucleic Acids; Pathogenesis; Pathologic; Pathology; Patients; Phase III Clinical Trials; Population; Population Dynamics; Process; Production; Proteins; Quality of life; RNA; Research; Research Personnel; Role; Senile Plaques; Severities; Shotguns; Soil; Structure; Tauopathies; Taxon; Techniques; Technology; Time; Transgenic Organisms; Vagus nerve structure; Volatile Fatty Acids; Water; Wild Type Mouse; abeta accumulation; aging population; base; beta pleated sheet; blood-brain barrier crossing; cognitive function; density; disorder prevention; disorder risk; gut microbiome; gut microbiota; gut-brain axis; host microbiome; host-associated microbial communities; human disease; human microbiota; in vivo; innovation; insight; interest; member; metagenomic sequencing; microbial; microbial community; microbial host; microbiome; microbiome composition; microbiome research; microbiome sequencing; microbiota; microorganism; mouse model; neuroinflammation; neuropathology; new technology; novel; pathogenic microbe; stable isotope; tool; vagus nerve stimulation; β-amyloid burden

ABSTRACT Alzheimer’s Disease (AD) is the leading cause of dementia in the aging population and severely impacts patient’s and caretaker’s quality of life. Despite decades of research, the underlying etiology of AD is incompletely understood. The prevailing hypothesis for AD pathology is the amyloid cascade hypothesis, which posits that the causative agent of AD is the accumulation of amyloid-β (Aβ, the main component of plaques) in the brain. However, recent Phase III clinical trials that target Aβ have not led to significant improvements in cognitive function, despite reducing overall brain Aβ burden. There has been a growing interest in understanding additional pathological features of AD that may impact disease progression. Recent studies in humans and in mice have suggested a role for pathogenic microbes or altered microbiota in neuroinflammation and AD. Microbiota in the GI tract can influence neurological health through microbial production of neurotransmitter precursors, immune-modulatory metabolites (e.g. short chain fatty acids), or interaction with the vagus nerve or enteric nervous system. Gut microbiota can also produce amyloids (aggregated, insoluble proteins exhibiting β-pleated sheet structures) that may cross the blood-brain barrier. Despite growing efforts to understand the gut microbiome-brain axis, current technologies using DNA or RNA amplicon sequencing are unable to address fundamental ecological questions, such as quantifying taxon-specific growth rates of host- associated microbiota. Understanding microbial ecosystem dynamics has large implications for human disease; quantifying growth or turnover of species in terms of absolute abundance change over time in an ecosystem can enable predictions of interspecies competition or trajectories of microbial succession in early and late life, which are associated with host health or disease risk. In this study, we will adapt an innovative technique widely used in soil microbial ecology to study host-microbiome dynamics in AD. We will use quantitative stable isotope probing (qSIP), a technique that uses an isotopically enriched substrate (e.g. 18O-water) to measure gut microbiome dynamics in triple transgenic (3xTg-AD) and wild- type mice. Since H2O is a universal substrate, labeled 18O will incorporate into microbial and host biomolecules, including nucleic acids; this feature allows a researcher to separate extracted DNA by density to quantify taxon-specific growth rates. Completion of this study will lead to the development of a novel tool that can be widely used in the AD community to better understand the contribution of host- associated microbiota to AD progression and neuroinflammation.

摘要 阿尔茨海默病(AD)是老年人群中痴呆的主要原因，严重 影响患者和照顾者的生活质量。尽管进行了数十年的研究，但该病的潜在病因 人们对广告的理解还不完全。阿尔茨海默病的流行假说是淀粉样级联反应 假说，认为阿尔茨海默病的病因是淀粉样蛋白-β(Aβ，主要 斑块的成分)。然而，最近针对Aβ的第三阶段临床试验并未导致 认知功能的显著改善，尽管总体上减少了大脑Aβ的负担。那里有 我越来越有兴趣了解AD的其他病理特征可能会影响 疾病的发展。最近在人类和小鼠身上的研究表明，致病因素 神经炎症和AD中的微生物或微生物区系改变。胃肠道中的微生物区系可以影响 通过微生物产生神经递质前体的神经健康，免疫调节 代谢物(如短链脂肪酸)，或与迷走神经或肠道神经系统的相互作用。 肠道微生物区系也可以产生淀粉样蛋白(聚集的、不可溶的蛋白质，表现为β-褶皱的片状 结构)可能会穿过血脑屏障。尽管人们越来越努力地了解它的内脏 微生物组-脑轴，目前使用DNA或RNA扩增子测序的技术无法 解决基本的生态问题，例如量化寄主特定于分类单元的增长率- 相关的微生物区系。了解微生物生态系统动力学对人类具有重大意义 疾病；用绝对丰度随时间的变化来量化物种的生长或周转 生态系统可以预测物种间的竞争或微生物演替的轨迹 在生命的早期和晚期，这与宿主健康或疾病风险有关。在这项研究中，我们将适应 一种广泛应用于土壤微生物生态学研究AD寄主-微生物群落动态的创新技术。 我们将使用定量稳定同位素探测(QSIP)，这是一种使用同位素浓缩的技术 底物(如18O-水)用于测量三重转基因(3xTg-AD)和野生-Tg-AD中的肠道微生物群动态 输入老鼠。由于H2O是一种通用底物，标记的18O将结合到微生物和宿主中 生物分子，包括核酸；这一特征允许研究人员通过以下方式分离提取的DNA 密度来量化特定于分类单元的增长率。这项研究的完成将导致 一种可以在AD社区中广泛使用的新工具，以更好地了解主机的贡献- 与AD进展和神经炎症相关的微生物区系。