The role of tissue nonspecific alkaline phosphatase in brain endothelial cell homeostasis

组织非特异性碱性磷酸酶在脑内皮细胞稳态中的作用

• 批准号: 10601067
• 负责人: Candice Brown
• 金额: $ 53.63万
• 依托单位: WEST VIRGINIA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10601067
• 关键词: Address; Age; Aging; Alkaline Phosphatase; Behavioral; Biology; Blood - brain barrier anatomy; Blood Preservation; Blood Vessels; Brain; Brain Diseases; Cell physiology; Cerebral Ischemia; Cerebrovascular Disorders; Cerebrum; Cre driver; Data; Disease; Endothelial Cells; Endothelium; Enzymes; Exhibits; Extravasation; Female; Foundations; Functional disorder; Gene Expression; Genetic; Health; Homeostasis; Human; Impairment; In Vitro; Injections; Injury; Ischemic Stroke; Knowledge; Label; Link; LoxP-flanked allele; Metabolism; Middle Cerebral Artery Occlusion; Minerals; Modeling; Molecular; Mus; Outcome; Pathologic; Pathway Analysis; Pathway interactions; Permeability; Physiological; Prediction of Response to Therapy; Recovery of Function; Regulation; Reperfusion Therapy; Rho-associated kinase; Role; Signal Pathway; Signal Transduction; Stroke; Testing; Therapeutic; Tissues; Tracer; Treatment Efficacy; age group; age related; aged; aging brain; aging population; artery occlusion; astrogliosis; behavioral outcome; blood-brain barrier permeabilization; bone; brain endothelial cell; brain health; cadherin 5; cerebral ischemic injury; cerebral microvasculature; cerebrovascular; conditional knockout; ecto-nucleotidase; enzyme activity; experimental group; fasudil; human disease; improved; in vivo; indexing; inhibitor; injured; male; middle age; mouse model; multiphoton microscopy; nervous system disorder; neurovascular unit; new therapeutic target; normal aging; novel; pharmacologic; post stroke; preservation; protective pathway; response; restoration; stroke outcome; therapeutic target; tool; translational impact

PROJECT SUMMARY The objective of this application is to determine how tissue nonspecific alkaline phosphatase (TNAP) enzymatic activity maintains cerebrovascular function within the neurovascular unit (NVU). Brain microvascular endothelial cells (BMECs) comprise the cerebral microvasculature and serve as the structural foundation of the blood-brain barrier (BBB) and. Increased permeability and diminished integrity of BMECs are two common mechanisms through which cerebrovascular function is compromised in human disease. TNAP is a highly enriched enzyme in cerebral microvessels whose function in brain BMECs is poorly understood. Our preliminary data demonstrate that TNAP activity stimulates a novel signaling mechanism which protects against the loss of cerebral microvascular integrity and permeability. These intriguing findings led us to propose the central hypothesis that TNAP maintains NVU homeostasis during cerebral ischemia by preserving BBB integrity. We will utilize mice with a VE-cadherin-Cre driven conditional deletion of TNAP in endothelial cells (VEcKO) and its wild type littermates to interrogate the role of TNAP in BMECs. We will compare responses in young (4-5 months) and aged (18-20 months) mice to assess the age-dependent effects of brain endothelial TNAP on indices of brain endothelial barrier permeability combined with vascular network analysis and functional behavioral outcomes. Aim 1 will elucidate the contribution of brain endothelial cell TNAP to NVU dysfunction in ischemic stroke in young mice. We will employ the transient middle artery occlusion model to assess quantitative differences in cerebrovascular outcomes and behavioral indices. Aim 2 will determine the impact of brain endothelial cell TNAP on age-dependent impairment of the NVU. This aim will assess the impact TNAP on BMEC function in aging and the putative age-dependent interactions in ischemic stroke. Aim 3 will determine how the TNAP-Rho associated kinase (ROCK) pathway regulates the barrier function and whether pharmacological inhibition of the ROCK pathway protects against the loss of barrier integrity and functional deficits associated ischemic stroke in both young and aged mice. Taken together, the studies in this proposal will delineate a novel mechanism through which brain endothelial cell TNAP enzyme activity preserves NVU function in ischemic stroke and improves functional recovery post-stroke. The overall results will contribute to our limited understanding of the basic biology of TNAP’s role at the BBB and its contribution to NVU homeostasis in human health and disease.

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 活动在神经血管单元（NVU）内保持脑血管功能。脑微血管内皮 细胞（BMEC）包括脑微脉管系统，并作为血脑的结构基础 障碍（BBB）和。渗透率提高和BMEC的完整性降低是两种常见机制 脑血管功能在人类疾病中受到损害。 TNAP是一种高度富集的酶 在脑BMEC中功能的脑微血管中，人们对此的功能知之甚少。我们的初步数据证明了 TNAP活性刺激了一种新型的信号传导机制，可防止脑丧失 微血管完整性和渗透性。这些有趣的发现使我们提出了一个中心假设，即 通过保持BBB完整性，TNAP在脑缺血期间保持NVU稳态。我们将利用老鼠 内皮细胞中TNAP的VE-Cadherin-Cre驱动的条件缺失及其野生型 同窝仔询问TNAP在BMEC中的作用。我们将比较年轻的回答（4-5个月）和 老年（18-20个月）的小鼠评估脑内皮TNAP对脑指数的年龄依赖性影响 内皮屏障渗透性与血管网络分析和功能行为结果相结合。 AIM 1将阐明脑内皮细胞TNAP对缺血性中风NVU功能障碍的贡献 年轻的老鼠。我们将采用瞬态中动脉闭塞模型来评估定量差异 脑血管结局和行为指数。 AIM 2将确定脑内皮细胞TNAP的影响 关于年龄依赖NVU的损害。此目标将评估衰老中BMEC功能的影响TNAP 以及缺血性中风中推定的年龄相互作用。 AIM 3将确定TNAP-RHO的方式 相关激酶（岩石）途径调节屏障功能以及药物抑制是否对 岩石途径可以防止屏障完整性的丧失，功能定义相关的缺血性中风 年轻小鼠和老年小鼠。综上所述，该提案中的研究将通过 哪种脑内皮细胞TNAP酶活性可保留缺血性中风的NVU功能并改善 中风后功能恢复。总体结果将有助于我们对基本的有限理解 TNAP在BBB中作用的生物学及其对NVU稳态在人类健康和疾病中的贡献。