Oxidative stress-induced vascular pathology and dysfunction in Alzheimer’s disease

阿尔茨海默病中氧化应激诱导的血管病理学和功能障碍

• 批准号: 10523897
• 负责人: Pradoldej Sompol
• 金额: $ 42.08万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10523897
• 关键词: 3-nitrotyrosine; Age; Aging; Alzheimer like pathology; Alzheimer' s Disease; Alzheimer' s disease brain; Alzheimer' s disease pathology; Alzheimer' s disease therapeutic; Amyloid beta-Protein; Animal Model; Animals; Astrocytes; Autopsy; Award; Basement membrane; Biological Markers; Blood Vessels; Blood capillaries; Blood flow; Brain; Cell Adhesion; Cerebrovascular Disorders; Cerebrum; Cognition; Complex; Confocal Microscopy; Contralateral; Dementia; Deposition; Development; Disease Progression; Dyes; Electrophysiology (science); Endothelial Cells; Extracellular Matrix Proteins; Extravasation; Fibronectins; Frequencies; Functional disorder; Future; Hemorrhage; Hippocampus (Brain); Human; Hyperemia; Image; Image Analysis; Imaging Techniques; Impaired cognition; Impairment; Individual; Infarction; Knowledge; Label; Laser Speckle Imaging; Lead; Link; Long-Term Potentiation; Measures; Mediating; Memory; Modeling; Monitor; Mus; Neuronal Dysfunction; Nitrogen; Oxidative Stress; Oxygen; Pathologic; Pathology; Peripheral; Peroxonitrite; Physiology; Pre-Clinical Model; Process; Proteins; Protocols documentation; Research Project Grants; Resolution; Resources; Rodent; Role; Rose Bengal; Route; Saline; Sampling; Slice; Specimen; Stimulus; Structure; Synapses; Synaptic plasticity; Techniques; Testing; Three-Dimensional Image; Thrombosis; Time; Tissue Harvesting; Tissues; Tyrosine; Validation; Vascular Diseases; Vibrissae; Work; amyloid pathology; arteriole; barrel cortex; brain tissue; cerebrovascular; cerebrovascular pathology; cognitive function; comorbidity; experimental study; imaging approach; insight; intravital imaging; macromolecule; microscopic imaging; microvascular pathology; mouse model; multiphoton imaging; multiphoton microscopy; neocortical; neurovascular; neurovascular coupling; non-demented; novel; oxidative damage; photoactivation; pre-clinical; synaptic function; thrombotic; time use; treatment strategy; two-photon; vascular cognitive impairment and dementia; vascular injury; vector

PROJECT SUMMARY/ ABSTRACT Vascular contributions to cognitive impairment and dementia (VCID) is highly comorbid with Alzheimer's disease (AD) where it exacerbates and hastens functional deficits. Mechanistic studies of vascular pathology formation and its effects on brain function, especially in AD, is limited. Developing translational imaging for application to mixed pathology models is necessary to understand the complex pathophysiological processes that link VCID and AD. Recently, we modified and optimized the oxidative stress-induced photothrombosis protocol (I.e. photoactivation of IV-injected Rose Bengal dye) for targeting individual capillaries in rodents. The major advantage of this novel vascular oxidative stress model is that vessel stalls, occlusion, and microhemorrhage can be followed in single capillaries in living mice, in real time, using multiphoton imaging. In this R21, we aim to apply this technique to 5xFAD mice to generate and characterize a novel AD/VCID mouse model en route to determining fibronectin— a matrix protein that supports vascular structure and integrity—as an indicator for the oxidative stress that arises from both cerebrovascular disease and AD. Our ongoing work on postmortem human brain specimens has revealed that astrocyte-derived fibronectin strongly colocalizes with the oxidative stress marker, nitrotyrosine (NT) especially around cerebrovessels and Aβ deposits. Photothrombosis of small cerebral arterioles revealed accumulation of fibronectin/NT colocalization at intravascular and nearby perivascular regions, similar to what we observe in human AD brain tissue. Here, we propose to use cutting edge physiology approaches combined with human postmortem brain specimens from our world class brain bank at the Sanders-Brown Center on Aging, to test the hypothesis that oxidative stress—indicated by NT incorporation into fibronectin— exacerbates cerebrovascular and synaptic dysfunction in the context of AD. In Aim 1, we will determine the effect of microvascular oxidative stress on neurovascular function in WT and 5xFAD mice. Multiphoton imaging techniques will be used to apply and to observe, in real-time, the development of microvascular pathologies including blood vessel stalls, vessel occlusion (infarct), and microhemorrhage as well as their effects on neurovascular coupling. Mouse brain tissues and postmortem samples from humans with confirmed vascular pathology and AD pathology will also be used to assess fibronectin/NT interactions with blood vessels, and to cross-validate our novel photothrombotic mouse model of mixed AD/VCID pathology. In Aim2, we will test the hypothesis that oxidative stress-induced microvascular pathology in 5xFAD mice leads to the global exacerbation of cognition and synaptic function in the context of AD-like pathology. The proposed studies will fill a critical knowledge gap surrounding the convergence of pathologic sequelae in cerebrovascular disease and AD. Moreover, establishment of a novel mouse model for mixed AD/VCID pathology will help inform new strategies for treating individuals with both AD and vascular pathology.

项目摘要/摘要 血管对认知损害和痴呆的贡献(VCID)与阿尔茨海默氏症高度共存 疾病(AD)，它会加剧和加速功能缺陷。血管病理学的机制研究 它的形成及其对大脑功能的影响是有限的，特别是在阿尔茨海默病。为以下项目开发平移成像 应用混合病理模型对于理解复杂的病理生理过程是必要的。 将VCID和AD联系起来。最近，我们对氧化应激诱导的光血栓形成进行了修饰和优化 (例如，静脉注射的孟加拉玫瑰染料的光活化)用于靶向啮齿动物的个别毛细血管。这个 这种新的血管氧化应激模型的主要优点是血管停滞、闭塞和 利用多光子成像技术，可以在活着的小鼠体内实时追踪单个毛细血管内的微出血。在……里面 在R21，我们的目标是将这项技术应用于5xFAD小鼠，以产生并鉴定一种新的AD/VCID小鼠 确定纤维连接蛋白的模型-一种支持血管结构和完整性的基质蛋白-AS 由脑血管疾病和阿尔茨海默病引起的氧化应激的指标。我们正在进行的工作 在尸检的人脑标本上发现，星形胶质细胞来源的纤维连接蛋白强烈共存 以氧化应激为标志，硝基酪氨酸(NT)尤其在脑血管周围和Aβ沉积。 光凝形成的大脑小动脉表现为纤维连接蛋白/NT共定位的聚集 血管内和附近的血管周围区域，类似于我们在人类AD脑组织中观察到的。在这里，我们 建议使用尖端生理学方法结合人类尸检脑组织标本 我们在桑德斯-布朗老龄化中心的世界级脑库，来测试氧化 应激--表明NT掺入纤维连接蛋白--加剧脑血管和突触 阿尔茨海默病中的功能障碍。在目标1中，我们将确定微血管氧化应激对 WT和5xFAD小鼠的神经血管功能。多光子成像技术将用于应用和 实时观察微血管病变的发展，包括血管停顿、血管 闭塞(梗塞)、微出血及其对神经血管偶联的影响。小鼠脑 确认血管病理和AD病理的人类组织和尸检样本也将 用于评估纤维连接蛋白/NT与血管的相互作用，并交叉验证我们的新发现 混合性AD/VCID病理的光血栓形成小鼠模型。在AIM2中，我们将测试氧化的假设 应激诱导的5xFAD小鼠微血管病变导致认知和认知功能的全面恶化 AD样病理背景下的突触功能。拟议中的研究将填补一个关键的知识空白 围绕脑血管病和AD的病理后遗症的汇聚。此外， 建立一种新的AD/VCID混合病理小鼠模型将有助于为治疗提供新的策略 患有阿尔茨海默病和血管病变的个体。