Neurovascular Adhesion Receptors and Barrier Integrity

神经血管粘附受体和屏障完整性

• 批准号: 7738486
• 负责人: Gregory J Del Zoppo
• 金额: $ 33.74万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-12-16 至 2011-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7738486
• 关键词: Address; Adhesions; Appearance; Astrocytes; Attention; Basal lamina; Binding; Blood; Blood - brain barrier anatomy; Blood Vessels; Brain; Brain Diseases; Brain Hypoxia-Ischemia; Cell Adhesion; Cells; Cerebrum; Data; DegP protease; Degenerative Disorder; Development; Dystroglycan; Endothelial Cells; Endothelium; Failure; Family; Glucose; Goals; Hypoxia; Integrins; Interruption; Ischemia; Ischemic Stroke; Lead; Liquid substance; Matrix Metalloproteinases; Mediating; Metalloproteases; Middle Cerebral Artery Occlusion; Neurons; Oxygen; Permeability; Phenotype; Plasma Cells; Receptor Cell; Research; Research Personnel; Role; Stroke; Testing; Therapeutic; Tight Junctions; Tissues; Work; adhesion receptor; base; clinically relevant; cohesion; deprivation; foot; inhibitor/antagonist; member; novel; receptor; receptor expression; relating to nervous system; small molecule

Ischemic stroke produces rapid profound loss of microvascular integrity. Early following focal ischemia detectable disruption in the permeability barrier of cerebral microvessels, and rapid changes in the matrix composition of their basal lamina occur. The hypotheses to be tested by this Proposal state i) that the interaction of matrix receptors on microvessel endothelial cells and astrocytes with the matrix components of the basal lamina are a major determinant of the blood-brain barrier phenotype, ii) that focal ischemia by middle cerebral artery occlusion (MCA:O) disrupts receptor-matrix interactions, and iii) that interruptions of the receptor-matrix interaction results in loss of the blood brain barrier phenotype. The phenotype of the permeability barrier involves the inter-endothelial tight junctions. But, adhesion of endothelial cells and astrocytes to the intact basal lamina matrix is also likely to be important. The vascular matrix is generated by endothelial cells and astrocytes in concert during development, and is maintained by both endothelial cells and astrocytes through their matrix adhesion receptors. Adhesion receptors which could bind cerebral microvascular endothelial cells and astrocytes to the basal lamina matrix include specific integrins and the a- and (3-dystroglycans. Based upon previous work and preliminary data, we propose that both integrins and dystroglycans are central to the integrity of the blood-brain and matrix barriers. The goal of this Project is to demonstrate that the action of specific members of these two adhesion receptor families is required for the integrity of the microvessel barrier functions, and that focal ischemia, hypoxia, and specific inhibitors that disrupt these receptor - matrix interactions, produce barrier failure. The Specific Aims are to: 1) Demonstrate that cell adhesion via cell receptors (integrins and dystroglycans) determine endothelial cell-matrix-astrocyte and blood brain barrier integrity; 2) Demonstrate that MCA:O or hypoxia significantly alter integrin-matrix and dystroglycan-matrix interactions at the endothelial cell-astrocyte interface; and 3) Demonstrate that the disruption of the cell adhesion receptor-matrix interactions occur independent of metalloproteinase expression. These studies provide a novel plausible explanation for the disruption of both the cerebral endothelial cell barrier to small molecules and the microvascular integrity immediately following focal ischemia. The specific use of select integrins and dystroglycans by astrocyte end-feet, and of PHntegrins by endothelial cells suggests the novel premise that their early disruption by focal ischemia is responsible for loss of the blood- brain barrier. Understanding the mechanisms of their expression and disruption is likely to lead to new testable approaches to preserve or selectively alter barrier function and microvessel integrity in other neurovascular degenerative disorders.

缺血性中风导致微血管完整性迅速严重丧失。局灶性缺血后早期