Generation and trans-neuronal seeding of phosphorylated T217-Tau in aging macaque cortical circuits

衰老猕猴皮层回路中磷酸化 T217-Tau 的生成和跨神经元播种

• 批准号: 10524449
• 负责人: Dibyadeep Datta
• 金额: $ 46.06万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10524449
• 关键词: Adult; Age; Aging; Alzheimer' s Disease; Alzheimer' s disease diagnosis; Alzheimer’s disease biomarker; Anatomy; Animals; Automobile Driving; Autophagocytosis; Autopsy; Binding; Biological Markers; Blood; Brain; Brain region; Calcium; Calcium-Binding Proteins; Calpain; Clinical; Cognition; Cyclic AMP-Dependent Protein Kinases; Data; Dendrites; Disease; Distal; Early Diagnosis; Early Intervention; Elderly; Europe; Event; Extracellular Space; Foundations; Frequencies; Generations; Glutamates; Hippocampus (Brain); Human; Immunoelectron Microscopy; Immunofluorescence Immunologic; Impaired cognition; Intervention; Invaded; Label; Learning; Macaca; Macaca mulatta; Measures; Mediating; Microscopy; Microtubules; Modeling; Molecular; Monkeys; Nerve Degeneration; Neurofibrillary Tangles; Neurons; Optics; Pathology; Pattern; Perfusion; Phosphorylation; Plasma; Positron-Emission Tomography; Prefrontal Cortex; Preventive treatment; Primates; Process; Proteins; Pyramidal Cells; Research; Resolution; Seeds; Smooth Endoplasmic Reticulum; Staging; Symptoms; Synapses; Techniques; Therapeutic Intervention; Threonine; Tissues; Vacuole; aged; aging brain; area striata; association cortex; blood-based biomarker; calbindin; diagnostic accuracy; end stage disease; entorhinal cortex; excitatory neuron; human old age (65+); human tissue; hyperphosphorylated tau; in vivo; indexing; interest; middle age; nanoscale; neurofibrillary tangle formation; neuronal cell body; neuropathology; nonalzheimer dementia; novel; preservation; tau Proteins; tau expression; tau phosphorylation; tau-1; trafficking

Abstract: There is great interest in the recent discovery of a novel, blood biomarker for Alzheimer’s Disease (AD), where levels of tau phosphorylated at threonine 217 (pT217-tau) in plasma herald ensuing disease decades before cognitive impairment. However, there is little known about how, when and where pT217-tau arises in the aging brain. The proposed research will utilize a novel rhesus macaque model with naturally occurring tau pathology to examine the pattern and sequence of pT217-tau expression in the aging cortex, and its relationship to calcium dysregulation and autophagic degeneration. Calcium dysregulation activates calpain, which cleaves GSK3β to hyperphosphorylate tau at T217, and cleaves heatshock protein 70.1 to drive autophagic degeneration, the process by which neurons die in AD. These events can be detected in the monkey model using perfusion-fixed tissue, which preserves early phosphorylation events and intracellular details that are often degraded in post-mortem human tissue, e.g., the ability to detect pT217-tau trafficking between neurons to “seed” higher cortical networks. The proposed research will examine how pT217-tau arises in vulnerable cortical regions (the entorhinal cortex and dorsolateral prefrontal cortex) compared with the more resilient primary visual cortex, in middle-aged (7-13 yrs), “young”-aged (17-23 yrs), and old aged (27-33 yrs) rhesus monkeys. The research will utilize 2 complementary techniques: 1) multi-label immunofluorescence (MLIF) with super-resolution STED microscopy to examine molecular interactions, and 2) immunoelectron microscopy (immunoEM) to view ultrastructural localization, including trafficking between neurons. Results will be compared to parallel studies of human brain being conducted by the Braak/delTredici and Hansson labs in Europe. We hypothesize that pT217-tau is a successful biomarker of ensuing AD, because it heralds the initiation of tau hyperphosphorylation and neuronal degeneration, and because its active inter-neuronal trafficking between neurons provides access to the extracellular space where it can be captured and transported to CSF/blood. Aim 1 will examine the pattern and sequence of pT217-tau expression in aging macaque cortex, and whether pT217-tau expression specifically arises in glutamatergic neurons with signs of calcium dysregulation evidenced by activated calpain-2 expression and low calbindin. ImmunoEM will detect the earliest signs of expression, e.g., aggregating on microtubules in distal dendrites. Aim 2 will determine whether pT217-tau can traffic between excitatory neurons to seed glutamatergic networks subserving cognition. Preliminary data indicate pT217-tau undergoes trans-synaptic spread via omega bodies across glutamate synapses. Aim 3 we will determine whether pT217-tau expression occurs in concordance with autophagic degeneration in dendrites. Elucidating the temporal sequence of pT217-tau pathology in vulnerable vs. resilient brain regions and mechanisms driving neurodegeneration would help to explain why this tau species is such an appropriate herald of ensuing AD to guide therapeutic intervention strategies.

摘要：最近发现的小说《阿尔茨海默氏病血液生物标志物》非常感兴趣 （AD），在等离子体预示中，苏氨酸217（pt217-tau）的Tau水平随后疾病 认知障碍前几十年。但是，关于如何，何时何地，pt217-tau鲜为人知 发生在衰老的大脑中。拟议的研究将利用一种新颖的恒河猕猴模型 发生tau病理学以检查衰老皮层中PT217-TAU表达的模式和序列，并且 它与钙失调和自噬变性的关系。钙失调激活钙蛋白酶， 将GSK3β裂解至T217的高磷酸化tau，并切割Heathock蛋白70.1驱动 自噬变性，神经元在AD中死亡的过程。这些事件可以在 使用灌注固定组织的猴子模型，该组织保留早期磷酸化事件和细胞内 通常在验尸后人体组织中降解的细节，例如检测PT217-TAU贩运的能力 在神经元中“种子”高层皮质网络之间。拟议的研究将研究PT217-TAU如何 在 在中年（7-13岁），“ Young”（17-23岁）和老年人（27-33）中，更多的弹性初级视觉皮层（7-13岁） 恒河猴。该研究将利用2种完整的技术：1）多标签免疫荧光 （MLIF）具有超分辨率STED显微镜检查分子相互作用，2）免疫电子 显微镜（免疫）以查看超微结构定位，包括神经元之间的运输。结果将 与Braak/Deltredici和Hansson Labs在 欧洲。我们假设PT217-TAU是随后的广告的成功生物标志物，因为它预示了 tau高磷酸化和神经元变性的启动，并且由于其活性神经元间 神经元之间的贩运可通往可以捕获的细胞外空间，并且 运送到CSF/血液。 AIM 1将检查衰老中PT217-TAU表达的模式和序列 猕猴皮质，以及PT217-TAU表达是否特别出现在谷氨酸能神经元中 钙失调通过活性的Calpain-2表达和低钙来蛋白表明。免疫将检测到 最早的表达迹象，例如，在远端树突中的微管上聚集。 AIM 2将确定 PT217-TAU是否可以在兴奋性神经元之间流动到种子谷氨酸能网络的潜在 认识。表明pt217-tau的初步数据通过欧米茄体经历跨突触的传播 谷氨酸突触。 AIM 3我们将确定PT217-TAU表达是否与 树突中的自噬变性。阐明易受伤害的PT217-TAU病理的临时序列 与弹性的大脑区域和驱动神经变性的机制有助于解释为什么这种tau 物种是随之而来的广告，以指导治疗干预策略。