Elucidating mechanisms of blood-brain barrier dysfunction in Alzheimer's disease using a molecularly and cellularly tunable in vitro model

使用分子和细胞可调的体外模型阐明阿尔茨海默病血脑屏障功能障碍的机制

• 批准号: 10358824
• 负责人: Samira Michelle Azarin
• 金额: $ 38.4万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10358824
• 关键词: Address; Alleles; Alzheimer' s Disease; Alzheimer' s disease patient; Alzheimer' s disease risk; Alzheimer' s disease therapy; Amyloid beta-Protein; Apolipoprotein E; Astrocytes; Attenuated; Behavior Therapy; Blood - brain barrier anatomy; Blood Circulation; Brain; Cell Differentiation process; Cell Maintenance; Clinical Trials; Cues; Disease; Disease Progression; Drug Targeting; Endothelial Cells; Etiology; Exhibits; Functional disorder; Genes; Genetic; Genome; Glucose; Goals; Human; Impaired cognition; In Vitro; Individual; Inflammatory; Intercellular Fluid; Intervention; Late Onset Alzheimer Disease; Link; Measures; Methods; Modeling; Molecular; Neuroimmune; Outcome; Output; Pathogenesis; Patients; Pericytes; Predisposition; Prevention strategy; Preventive measure; Property; Protein Isoforms; Proteins; Reactive Oxygen Species; Research; Resolution; Risk; Risk Factors; Route; Signal Transduction; System; Testing; Therapeutic; Therapeutic Intervention; Translating; Work; abeta accumulation; apolipoprotein E-4; blood-brain barrier function; brain endothelial cell; cytokine; design; druggable target; genetic risk factor; human stem cells; in vitro Model; in vivo; induced pluripotent stem cell; insight; modifiable risk; new therapeutic target; non-genetic; novel; prevent; response; stem; stem cell model; therapeutic target

PROJECT SUMMARY Dysfunction of the blood-brain barrier (BBB) begins during early stages of Alzheimer’s Disease (AD) and contributes to AD pathogenesis in a manner both independent of and dependent on the accumulation of amyloid beta. The ε4 allele of the APOE gene is the greatest genetic risk factor for late-onset AD, but the molecular mechanisms underlying the connection between the APOE-ε4 allele and BBB dysfunction and are not well understood. In addition, the extent to which non-genetic risk factors for AD act alone and synergistically with the APOE-ε4 allele to disrupt BBB integrity and function is not known. The objective of this work is to gain mechanistic insight into how the APOE-ε4 allele and modifiable risk factors for AD influence BBB functions that are known to be disrupted in AD patients, with the goal of utilizing this information to identify novel therapeutic targets and/or interventive measures to prevent cognitive decline. Toward this end, human induced pluripotent stem cells (hiPSCs) will be used to generate isogenic models of the BBB with tunable molecular and cellular components. These models will be used to test our central hypothesis that expression of ApoE4, encoded by APOE-ε4, inherently alters the dynamics of key BBB functions and that molecular features of modifiable risk factors for AD compound these effects. The proposed research consists of two aims. (1) Determine the dominant molecular mechanisms by which ApoE4 effectuates BBB dysfunction for the prioritization of drug targets in early stage AD. Brain microvascular endothelial cells, pericytes, and astrocytes will be differentiated from hiPSCs containing either zero, one or two copies of the APOE-ε4 allele for quantitative analysis of how ApoE4 impacts dysregulated BBB transport, neuroimmune, and cell maintenance functions associated with AD pathogenesis. (2) Determine how molecular features common among modifiable risk factors for AD act in combination to drive BBB dysfunction and whether BBB susceptibility to these factors is ApoE-isoform dependent. In vitro BBB models of differing APOE status will be subjected to conditions that mimic modifiable risk factors for AD at the cellular level, including elevated concentrations of glucose, and inflammatory cytokines. This will be done using a fractional factorial design approach to systematically and efficiently evaluate combinations of genetic and non- genetic factors. Analysis of downstream signaling nodes will elucidate mechanistic connections between input cues and output responses, identifying druggable targets for therapeutic intervention. This approach will establish a detailed understanding of how the APOE-ε4 allele and modifiable risk factors act in concert to convey risk for AD through BBB dysfunction, providing preventative strategies and novel routes for therapeutic intervention in the early stages of AD, particularly in individuals with the APOE-ε4 allele.

项目摘要 血脑屏障（BBB）功能障碍始于阿尔茨海默病（AD）的早期阶段， 以独立和依赖于淀粉样蛋白积累的方式促进AD发病 β的载脂蛋白E基因的ε4等位基因是晚发性AD的最大遗传危险因素，但其分子遗传学特征是： APOE-ε4等位基因与血脑屏障功能障碍之间的潜在联系机制， 明白此外，AD的非遗传风险因素单独作用以及与 APOE-ε4等位基因破坏BBB完整性和功能尚不清楚。这项工作的目的是获得 对APOE-ε4等位基因和AD的可改变的危险因素如何影响BBB功能的机制性认识， 已知在AD患者中被破坏，目的是利用这些信息来鉴定新的治疗药物， 目标和/或干预措施，以防止认知能力下降。为此，人类诱导多能 干细胞（hiPSC）将用于产生具有可调分子和细胞生物学特性的BBB的等基因模型。 件.这些模型将用于检验我们的中心假设，即ApoE 4的表达， APOE-ε4，固有地改变了关键BBB功能的动力学， AD的因素复合了这些影响。拟议的研究包括两个目标。(1)确定主导 ApoE 4影响血脑屏障功能障碍的分子机制，以优先考虑早期药物靶点。 AD期。脑微血管内皮细胞、周细胞和星形胶质细胞将从hiPSC分化 含有0、1或2个拷贝的APOE-ε4等位基因，用于定量分析ApoE 4如何影响 与AD发病机制相关的BBB转运、神经免疫和细胞维持功能失调。 (2)确定AD可改变的风险因素中常见的分子特征如何联合作用， BBB功能障碍和BBB对这些因素的易感性是否是ApoE亚型依赖性的。体外BBB 不同APOE状态的模型将经受模拟AD的可改变的风险因素的条件， 细胞水平，包括葡萄糖浓度升高和炎性细胞因子。这将使用 采用部分因子设计方法，系统有效地评估遗传和非遗传因素的组合， 遗传因素下游信令节点的分析将阐明输入之间的机械连接 提示和输出反应，确定药物治疗干预的目标。这种方法将 详细了解APOE-ε4等位基因和可改变的风险因素如何协同作用， 通过BBB功能障碍降低AD风险，提供预防策略和治疗AD的新途径。 在AD的早期阶段进行干预，特别是在具有APOE-ε4等位基因的个体中。