Novel Signaling Pathways in Ischemic Stroke

缺血性中风的新型信号通路

基本信息

批准号：
8415552
负责人：
JAMES Kuang-Jan LIAO
金额：
$ 32.69万
依托单位：
UNIVERSITY OF CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-02-01 至 2015-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8415552
关键词：
Actins Acute Adhesions Affect Agonist Arteriosclerosis Atherosclerosis Blood Clot Blood Platelets Blood Vessels Blood coagulation Blood flow Bone Marrow Transplantation Calcium Carotid Artery Injuries Cause of Death Cells Cerebral Infarction Cerebral Ischemia Cerebrovascular Circulation Cerebrovascular Spasm Cerebrum Cessation of life Coagulation Process Coronary Artery Vasospasm Cyclic AMP-Dependent Protein Kinases Cytoskeleton Data Development Disease Electron Microscopy Event Filament Functional disorder Generations Genetic Goals Homo Human Hydroxymethylglutaryl-CoA Reductase Inhibitors Hypertension Imagery In Vitro Infarction Inflammation Inflammatory Integrins Ischemic Stroke Knock-out Knockout Mice LIM Domain Kinase 1 Lead Leukocytes Link MAP Kinase Gene Measurement Mediating Methods Middle Cerebral Artery Occlusion Modeling Mus Necrosis Neuronal Injury Pathway interactions Patients Phosphotransferases Platelet Activation Platelet aggregation Play Production Protein Isoforms Protein-Serine-Threonine Kinases ROCK1 gene Research Rho-associated kinase Role Signal Pathway Signal Transduction Societies Stroke Structure Technology Testing Thrombin Thrombosis Thromboxane A2 Thrombus Tissues Up-Regulation Whole Blood disability fasudil filamin human NOS3 protein in vivo inhibitor/antagonist loss of function mouse model neurovascular unit novel prevent public health relevance receptor response rho therapeutic target vascular inflammation

项目摘要

DESCRIPTION (provided by applicant): The activation of platelets is the final common pathway for most ischemic strokes. Acute thrombus formation in the setting of vascular dysfunction and inflammation initiates a cascade of events that culminates in necrotic death of neurons and injury to their supportive structures in the neurovascular unit. However, the signaling pathways that link these events are not well understood. The Rho/Rho-associated coiled-coil forming kinases (ROCK1 and ROCK2) are important regulators of the actin cytoskeleton. Because changes in the actin cytoskeleton underlie platelet aggregation, vascular contractility, and inflammatory cell recruitment, it is likely that the Rho/ROCK pathway will play a central role in ischemic strokes. Accordingly, the overall aim of this proposal is to investigate the role of ROCK isoforms in platelets and to determine how they might contribute to thromboembolic strokes. To achieve this goal, we will target ROCK deletion in platelets using knockout (KO), bone marrow transplantation (BMT), and Cre/loxP technology and will investigate the subsequent loss-of-function of platelet ROCKs in thrombus formation, clot propagation, and focal cerebral ischemia. The results of these proposed studies will hopefully lead to the development of isoform-specific ROCK inhibitors as novel therapies for patients with ischemic strokes. Specific aim 1 will determine the mechanisms by which ROCKs contribute to platelet function and arterial thrombosis. We will test the hypothesis that ROCKs play differential roles in regulating the assembly of the platelet cytoskeleton and mediating platelet function. To determine and compare the effect of ROCK1 and ROCK2 on thrombosis, platelets derived from ROCK1-/- and ROCK2-/- bone marrow transplanted (BMT) mice will be studied for aggregation, adhesion, hetero- and homo-typic aggregate formation, and by direct visualization with electron microscopy after activation with various platelet agonists. Furthermore, we will investigate the potential downstream signaling pathways of ROCKs that regulates platelet actin cytoskeleton and function. Specific aim 2 will determine the pathophysiological consequences of platelet ROCK deletion on thrombus formation and propagation in a clot embolic model of stroke. We will test the hypothesis that ROCKs are critically important for platelet function in vivo, and that platelet deletion of ROCKs confers stroke protection in a mouse model of thrombosis-mediated focal cerebral ischemia. To do this, we will develop platelet-specific ROCK KO mice (ROCK1Plt-/- and ROCK2Plt-/- mice) and utilize (1) a carotid artery injury model for measurement of arterial occlusive thrombosis, (2) an agonist-dependent platelet consumptive model to study micro thrombi formation, and (3) a clot-embolic stroke model using preformed thrombi to determine the ability of a clot to form and adhere to the vasculature, mediate vascular occlusion, and cause cerebral ischemia and infarction.

描述（由申请人提供）：血小板的激活是大多数缺血性中风的最终常见途径。在血管功能障碍和炎症的情况下，急性血栓形成引发了一系列事件，这些事件最终导致神经元坏死死亡以及对神经血管单元中其支撑性结构的损伤。但是，连接这些事件的信号传导途径尚不清楚。 Rho/Rho相关的盘绕螺旋形成激酶（Rock1和Rock2）是肌动蛋白细胞骨架的重要调节剂。由于肌动蛋白细胞骨架的变化是血小板聚集，血管收缩力和炎性细胞募集的基础，因此Rho/Rock途径很可能在缺血性中风中起核心作用。因此，该提案的总体目的是研究岩石同工型在血小板中的作用，并确定它们如何有助于血栓栓塞中风。为了实现这一目标，我们将使用敲除（KO），骨髓移植（BMT）和CRE/LOXP技术在血小板中靶向岩石缺失，并将研究血栓形成，凝块繁殖和局灶性脑局部局部缺血中血小板岩石在随后的功能丧失。这些提出的研究的结果有望导致同工型特异性岩石抑制剂作为缺血性中风患者的新疗法的发展。特定的目标1将确定岩石对血小板功能和动脉血栓形成的贡献的机制。我们将检验以下假设：岩石在调节血小板细胞骨架和介导血小板功能方面起差异作用。为了确定和比较Rock1和Rock2对血栓形成的影响，将研究源自Rock1 - / - 和Rock2 - / - 骨髓移植（BMT）小鼠的血小板，以进行聚集，粘附，异性和同型型聚合形成，并通过与各种Platelet Platelet Agonist exture Microscopey Cobilation Cobilation Cobilation Cobilation cobilation cobilation covilation covilation cockitation cockitation in Castection sourdelet oferselet oferselet oferselet oferselet oferselet affertelet。此外，我们将研究调节血小板肌动蛋白细胞骨架和功能的岩石的潜在下游信号通路。特定的目标2将确定血小板缺失在凝块栓塞模型中血小板缺失对血栓形成和传播的病理生理后果。我们将检验以下假设：岩石对于体内的血小板功能至关重要，并且在血栓形成介导的局灶性脑缺血的小鼠模型中，岩石的血小板缺失赋予了中风保护。 To do this, we will develop platelet-specific ROCK KO mice (ROCK1Plt-/- and ROCK2Plt-/- mice) and utilize (1) a carotid artery injury model for measurement of arterial occlusive thrombosis, (2) an agonist-dependent platelet consumptive model to study micro thrombi formation, and (3) a clot-embolic stroke model using preformed thrombi to determine the ability of形成并遵守脉管系统的凝块，介导血管闭塞，并引起脑缺血和梗塞。