Platelet AADACL1 in thrombosis, lipidomics and signaling

血小板 AADACL1 在血栓形成、脂质组学和信号传导中的作用

• 批准号: 8987368
• 负责人: STEPHEN P HOLLY
• 金额: $ 39.44万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8987368
• 关键词: Address; Adhesions; Affect; Agonist; Animal Model; Arterial Fatty Streak; Attenuated; Binding; Biological; Biological Assay; Bleeding time procedure; Blood; Blood Platelets; Blood Vessels; Cells; Coagulation Process; Collagen; Complex; DAG/PE-Binding Domain; Data; Deacetylase; Dimensions; Disease; Effectiveness; Embolism; Enzymes; Epinephrine; Ethers; Event; Exhibits; Fibrinogen; Genetic screening method; Hemorrhage; Hemostatic function; Human; Hydrolase; Inflammation; Injection of therapeutic agent; Injury; Knock-out; Knowledge; Laser injury; Lead; Link; Lipids; Lung; Mass Spectrum Analysis; Measures; Mediating; Megakaryocytes; Metabolic; Metabolic Pathway; Metabolism; Methodology; Modeling; Molecular; Molecular Target; Mus; Myocardial Infarction; Output; Pathway interactions; Physiological; Platelet Activation; Platelet aggregation; Process; Property; Protein Isoforms; Proteome; Rattus; Risk; Role; Rupture; Saphenous Vein; Scanning; Serine Hydrolase; Signal Pathway; Signal Transduction; Stimulus; Stroke; Surveys; Testing; Therapeutic; Thrombosis; Thrombus; Time; base; cell type; cerebrovascular; combat; genetic approach; in vivo; in vivo Model; inhibitor/antagonist; lipid metabolism; member; new therapeutic target; novel; novel strategies; prevent; prospective; public health relevance; research study; response; small molecule; therapeutic target

 DESCRIPTION (provided by applicant): Activated platelets can induce myocardial infarction and cerebrovascular thrombosis, whereas insufficient platelet activation can result in pathological blood loss. A better understanding of the complex network of events that govern platelet activation could lead to the identification of new therapeutic targets that mitigate thrombosis without significantly increasing bleeding. We previously used a novel chemoproteomic approach to identify arylacetamide deacetylase-like 1 (AADACL1) as a lipid hydrolase in human platelets. We found that AADACL1 is required for agonist-stimulated platelet aggregation and thrombus formation but not platelet adhesion ex vivo. Exciting new data indicate that AADACL1 inhibition significantly prolongs occlusion time in a rat model of thrombosis, suggesting that blocking AADACL1 activity in vivo may effectively reduce thrombosis while preserving other aspects of hemostasis, a hypothesis that we will test in Specific Aim 1. Even though AADACL1 activity contributes to the signaling output of multiple platelet agonists, we have only a cursory understanding of its substrates, products and mechanism of action in platelet aggregation. Obtaining this fundamental knowledge is crucial for evaluating the scope of AADACL1 action in platelets and determining the prospective value of AADACL1 and its substrates, and products as potential regulators of thrombosis. Therefore, in Specific Aim 2 we propose to define the metabolic footprint of AADACL1 in platelets via global and targeted mass spectrometry-based lipidomics. Finally, we determined that AADACL1 is required for optimal activation of Rap1 and PKC, two platelet signaling nodes critical to the platelet activation process in response to multiple agonists. Although the mechanism by which AADACL1 regulates these key signaling nodes is unknown, our intriguing preliminary data suggest that ether lipids metabolized by AADACL1, may function as endogenous regulators of platelet signaling at least in part via direct interaction with the C1 domains of PKC, a hypothesis that will be tested in Specific Aim 3. Completion of these studies will help us dissect an entirely novel lipid signaling pathway in platelets and probe the biological implications of AADACL1 metabolism in thrombosis and hemostasis.

 描述（由申请人提供）：活化的血小板可诱导心肌梗死和脑血管血栓形成，而血小板活化不足可导致病理性失血。更好地了解控制血小板活化的复杂事件网络可能会导致识别新的治疗靶点，从而减轻血栓形成而不会显着增加出血。我们以前使用了一种新的化学蛋白质组学方法，以确定芳基乙酰胺脱乙酰酶样1（AADACL1）作为一种脂质水解酶在人类血小板。我们发现AADACL1是激动剂刺激的血小板聚集和血栓形成所必需的，但不是离体血小板粘附所必需的。令人兴奋的新数据表明，在大鼠血栓形成模型中，AADACL1抑制显著延长了闭塞时间，这表明在体内阻断AADACL1活性可以有效减少血栓形成，同时保留止血的其他方面，我们将在特定目标1中检验这一假设。尽管AADACL1活性有助于多种血小板激动剂的信号输出，但我们对其在血小板聚集中的底物、产物和作用机制只有粗略的了解。获得这些基础知识对于评估AADACL1在血小板中的作用范围以及确定AADACL1及其底物和产物作为血栓形成潜在调节剂的预期价值至关重要。因此，在具体目标2中，我们建议通过基于全局和靶向质谱的脂质组学来定义AADACL1在血小板中的代谢足迹。最后，我们确定AADACL 1是Rap 1和PKC最佳激活所需的，Rap 1和PKC是对多种激动剂反应的血小板激活过程至关重要的两个血小板信号传导节点。虽然AADACL1调节这些关键信号节点的机制尚不清楚，但我们有趣的初步数据表明，由AADACL1代谢的醚脂质可能至少部分通过与PKC的C1结构域直接相互作用而作为血小板信号传导的内源性调节剂发挥作用，这是一种假设。 这将在具体目标3中进行测试。完成这些研究将有助于我们彻底剖析 血小板中新的脂质信号传导途径，并探讨AADACL1代谢在血栓形成和止血中的生物学意义。