A protective role for endothelial cell tissue nonspecific alkaline phosphatase in ischemic stroke

内皮细胞组织非特异性碱性磷酸酶在缺血性中风中的保护作用

基本信息

批准号：
10025934
负责人：
Candice Brown
金额：
$ 26.6万
依托单位：
WEST VIRGINIA UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-08 至 2025-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10025934
关键词：
Acute Address Alkaline Phosphatase Behavioral Blood - brain barrier anatomy Blood Circulation Blood Preservation Brain Brain Diseases Centers of Research Excellence Cerebral Ischemia Cerebrovascular Disorders Cerebrum Coupled Cyclic AMP Cytoskeletal Proteins Data Development Endothelial Cells Enzymes Experimental Designs Experimental Models Functional disorder Funding Genetic Glucose Homeostasis Impairment In Vitro Inflammatory Injury Ischemia Ischemic Stroke Knowledge Laboratories Link Mediating Metabolism Middle Cerebral Artery Occlusion Minerals Modeling Molecular Mus Outcome Oxidative Stress Oxygen Pathologic Pathway interactions Permeability Pharmacology Phase Phenotype Phosphotransferases Physiological Recovery of Function Reperfusion Injury Reperfusion Therapy Research Research Personnel Rho-associated kinase Role Signal Pathway Signal Transduction Stroke Structure Testing Therapeutic Intervention Tissues Universities West Virginia artery occlusion blood-brain barrier function blood-brain barrier permeabilization bone brain endothelial cell brain health cerebral ischemic injury cerebral microvasculature deprivation design effective therapy enzyme activity experimental study functional loss improved in vitro Model in vivo inhibitor/antagonist injured insight mouse model nervous system disorder new therapeutic target novel post stroke prevent rho stroke survivor targeted treatment tool translational impact

项目摘要

PROJECT SUMMARY The objective of this application is to determine how tissue nonspecific alkaline phosphatase (TNAP) enzymatic activity preserves blood-brain barrier (BBB) function in ischemic stroke. Increased BBB permeability and oxidative stress are two potential mechanisms through which cerebral ischemia and reperfusion injury elicit BBB dysfunction and subsequent functional deficits in acute ischemic stroke. TNAP is a highly enriched enzyme in cerebral microvessels whose function in brain microvascular endothelial cells (BMECs) is poorly understood. Our preliminary data generated in a cellular BBB model of ischemia-reperfusion injury demonstrate that TNAP activity stimulates a novel mechanism which enhances cAMP-mediated signaling pathways that suppress Rho kinase (ROCK) activity and preserve BBB function. These intriguing findings led us to propose the novel concept that, in the face of cerebral ischemic injury, TNAP-ROCK signaling mechanisms integrate systemic signals at the BBB to sustain cerebral function and protect against post-stroke behavioral deficits. To address this novel concept, the application will investigate the central hypothesis that protection from ischemic stroke-induced impairment of BBB function is mediated by brain endothelial cell TNAP and its associated signaling cascades. The proposed studies will test this hypothesis in a mouse model of experimental ischemic stroke, transient middle cerebral artery occlusion (tMCAO), and in an ex vivo model of ischemia-reperfusion injury, oxygen-glucose deprivation (OGD). The experimental design will employ a mouse model with conditional deletion of TNAP in endothelial cells (VE-cKO) and its wild type littermates to interrogate TNAP’s effects on BBB permeability, short- term functional recovery, and BMEC signaling pathways post-stroke. Aim 1 will elucidate how TNAP preserves BBB permeability and promotes barrier function during cerebral ischemia and reperfusion injury. Aim 2 will interrogate the role of TNAP-ROCK signaling mechanisms in an OGD model of injury. Aim 3 will integrate the experiments in Aims 1 and 2 to prepare a competitive R01 application that will lead to independence of COBRE funding. Taken together, the studies in this proposal will uncover novel insights into the mechanisms that link TNAP enzyme activity to BBB integrity, barrier function, short-term functional recovery in ischemic stroke. The translational impact of these studies may uncover TNAP and its associated signaling cascades as novel therapeutic targets in ischemic stroke and other cerebrovascular disorders.

项目摘要该应用的目的是确定组织非特异性酒精磷酸酶（TNAP）酶促的酶促如何活性保留缺血性中风中的血脑屏障（BBB）功能。 BBB渗透性增加和氧化应激是两个潜在的机制，脑缺血和再灌注损伤引起了BBB 急性缺血性中风的功能障碍和随后的功能缺陷。 TNAP是一种高度富集的酶脑微血管在脑微血管内皮细胞（BMEC）中的功能知之甚少。我们在缺血再灌注损伤的细胞BBB模型中产生的初步数据表明TNAP 活动刺激了一种新的机制，该机制增强了camp介导的信号通路，从而抑制Rho 激酶（岩石）活性并保留BBB功能。这些有趣的发现使我们提出了新颖的概念面对脑缺血性损伤，TNAP-ROCK信号机制在 BBB维持脑功能并防止势后行为定义。解决这本小说概念，该应用将调查中心假设，即防止缺血性中风引起的保护 BBB功能的损害是由脑内皮细胞TNAP及其相关信号级联反应介导的。拟议的研究将在实验性缺血性中风的小鼠模型中检验该假设脑动脉闭塞（TMCAO），在缺血 - 再灌注损伤的离体模型中，氧气 - 葡萄糖剥夺（OGD）。实验设计将采用带有条件删除TNAP的鼠标模型内皮细胞（VE-CKO）及其野生型同意物，以询问TNAP对BBB渗透性的影响，短期中风后术语功能恢复和BMEC信号通路。 AIM 1将阐明TNAP如何保存 BBB渗透性并促进脑缺血和再灌注损伤期间的屏障功能。 AIM 2意志询问TNAP-ROCK信号传导机制在OGD损伤模型中的作用。 AIM 3将整合 AIM 1和2中的实验准备竞争性的R01应用，该应用将导致Cobre独立资金。综上所述，该提案中的研究将发现有关联系机制的新发现 TNAP酶的活性，可抗BBB完整性，屏障功能，缺血性中风的短期功能恢复。这这些研究的翻译影响可能会发现TNAP及其相关的信号级联缺血性中风和其他脑血管疾病的治疗靶标。