Pathogenic Mechanisms of Cell-Derived Abeta Oligomers

细胞源性 Abeta 寡聚物的致病机制

• 批准号: 7027342
• 负责人: DENNIS J SELKOE
• 金额: $ 44.18万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7027342
• 关键词: Alzheimer' s disease; amyloid proteins; binding proteins; cell line; chemical aggregate; crosslink; embryo /fetus tissue /cell culture; genetically modified animals; hippocampus; laboratory mouse; laboratory rat; mass spectrometry; molecular pathology; neurotoxins; phosphorylation; polymerization; synapses; tau proteins; Alzheimer' s disease; amyloid proteins; binding proteins; cell line; chemical aggregate; crosslink; embryo /fetus tissue /cell culture; genetically modified animals; hippocampus; laboratory mouse; laboratory rat; mass spectrometry; molecular pathology; neurotoxins; phosphorylation; polymerization; synapses; tau proteins

DESCRIPTION (provided by applicant): An enduring principle for successful intervention in human disease is to identify - and then prevent - the earliest steps in pathogenesis. In the case of Alzheimer's disease and its harbinger, mild cognitive impairment (MCI), studies from many labs support the still unproven hypothesis that the gradual accumulation and oligomerization of amyloid p-protein (AB) in brain regions serving memory and cognition initiates this complex syndrome. Given the enormous resources being expended by academic and pharmaceutical scientists to identify anti-amyloid therapies and bring them to human trials, it is crucial to understand precisely how soluble AB begins to oligomerize and whether this process actually induces the subtle compromise of synaptic function seen in MCI and early AD. In this new RO1 application, investigators who have collaborated productively to discover the natural secretion of low-n AB oligomers in cell culture and then demonstrate their ability to inhibit long-term potentiation and disrupt memory in living animals now propose to rigorously define at the molecular level these earliest AB assembly forms and elucidate their mechanisms of action on neuronal function. Based on extensive preliminary data and sensitive biochemical methods we have developed to isolate and study natural oligomers, we propose 4 interrelated Specific Aims. 1. Determine the precise molecular composition of naturally secreted AB oligomers by mass spectrometry and search for covalent crosslinks, associated small molecules and/or binding proteins that may contribute to their potent neuronal activity. 2. Characterize the effects of the natural oligomers on synaptic form and function, including in organotypic hippocampal cultures, and assess whether they can induce AD-type tau phosphorylation and altered transmitter release in vivo, 3. Purify the natural oligomers to homogeneity, intrinsically label them and identify their cognate molecular and cellular targets in living brain. 4. Assess 3 specific therapeutic strategies to decrease the production of cell-secreted oligomers and thereby abrogate their synaptotoxicity: (B- or y-secretase inhibitors; certain anti-aggregation compounds; and chaperone expression. Our extensive experience in studying this unlimited cellular source of physiological amounts of human AB oligomers should enable us to exploit this unique experimental paradigm to elucidate both the nature and the neuronal effects of the earliest AB assemblies, with attendant therapeutic implications. Relevance to Public Health: Because our central hypothesis is that the earliest-forming "oligomers" (doublets, triplets, etc.) of amyloid B-protein underlie the subtle and progressive impairment of memory that is the hallmark of incipient AD, we will use a unique experimental system in which cultured cells naturally produce such early forms in order to decipher the precise nature of these pathogenic assemblies, identify their mechanism of injury on the neurons and synapses required for memory, and then block this process with novel drugs.

描述（由申请人提供）：成功干预人类疾病的持久原则是识别（然后预防）发病机理的最早步骤。就阿尔茨海默氏病及其预兆，轻度认知障碍（MCI）而言，来自许多实验室的研究支持了仍然未经证实的假设，即在脑区域中淀粉样蛋白P蛋白（AB）的逐渐积累和寡聚，在记忆和认知启动中，这种复杂的综合症。鉴于学术和药物科学家花费了巨大的资源来识别抗淀粉样蛋白疗法并将其带入人类试验，因此准确地理解可溶性AB如何开始寡聚以及这一过程是否真的引起了MCI和早期AD中的突触功能的微妙妥协，这一点至关重要。在这一新的RO1应用中，有效合作以发现细胞培养中低N AB低聚物的自然分泌，然后证明其抑制长期增强和破坏活动物中的记忆的能力现在，现在建议以分子级的严格定义这些最早的AB组装形式，并阐明其对神经元功能的作用机制。基于广泛的初步数据和敏感的生化方法，我们开发了隔离和研究天然低聚物，我们提出了4个相互关联的特定目标。 1。通过质谱法确定天然分泌的AB低聚物的精确分子组成，并搜索可能有助于其有效的神经元活性的共价交叉链接，相关的小分子和/或结合蛋白。 2。表征天然低聚体对突触形式和功能的影响，包括在器官海马培养物中，并评估它们是否可以诱导Ad-type tatepe tau磷酸化并改变了体内的发射机释放，3。将天然的低聚物净化为同质性，内在地标记它们并识别出它们的认识和细胞的coptarate核心和细胞的细胞和细胞。 4。评估3种特定的治疗策略，以减少细胞分泌的低聚物的产生，从而消除它们的突触毒性：（B-或Y-凝聚酶抑制剂；某些抗凝聚化合物和伴侣蛋白的表达；我们在研究这种无效的人类体验的无效的人类构图的范围来实验性的经验来实验性的人类囊泡量，以实现这种实验性，以实验性地进行实验。最早的AB组装的性质和神经元作用都具有与公共健康相关的含义。为了破译这些病原体组件的精确性质，确定其对记忆所需的神经元和突触的损伤机理，然后用新型药物阻止此过程。