Protease Activated Receptor Signaling by Coagulation Proteases

凝血蛋白酶激活的蛋白酶受体信号传导

• 批准号: 9380129
• 负责人: ALIREZA R. REZAIE
• 金额: $ 43.38万
• 依托单位: OKLAHOMA MEDICAL RESEARCH FOUNDATION
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9380129
• 关键词: Abdomen; Adhesions; Adhesives; Advanced Glycosylation End Products; Affinity; Animal Model; Anti-Inflammatory Agents; Anti-inflammatory; Antioxidants; Binding; Biological Assay; Blood Platelets; CaM kinase I activator; Cardiac; Cell Surface Receptors; Cell model; Cell surface; Cells; Coagulation Process; Complex; Coupled; Cyclic AMP; Data; Development; Disease; Down-Regulation; Endothelial Cells; Event; F2R gene; FRAP1 gene; G-Protein-Coupled Receptors; G-substrate; GTP-Binding Proteins; Generations; HMGB1 Protein; Immunoblotting; Immunoprecipitation; In Vitro; Inflammation; Inflammatory; Inflammatory Response; Injury; Ischemia; Lead; Ligands; Mediating; Methods; Modeling; Monitor; Mus; Myocardial; Myocardial Infarction; Myocardial Ischemia; Names; Nuclear; Operative Surgical Procedures; Organ; Oxidation-Reduction; PAR-1 Receptor; Pathogenesis; Pathologic; Pathway interactions; Patients; Pelvis; Peptide Hydrolases; Peritoneal; Peritoneal Fluid; Pharmaceutical Preparations; Phosphorylation; Physiological Processes; Polyphosphates; Polyps; Process; Production; Protein C; Proteinase-Activated Receptors; Proteins; Reactive Oxygen Species; Receptor Signaling; Regulation; Reperfusion Injury; Reperfusion Therapy; Role; Sepsis; Signal Pathway; Signal Transduction; Signaling Molecule; Site; Specificity; Structure; Surgical incisions; Tertiary Protein Structure; Therapeutic; Thrombin; Tissues; Vascular Endothelial Cell; activated Protein C; activated protein C receptor; alpha-Thrombin; base; cell injury; cytokine; enteropeptidase; epigenetic regulation; in vivo; insight; mouse model; mutant; p66(ShcA) protein; public health relevance; purinoceptor P2Y1; receptor; response

DESCRIPTION (provided by applicant): Coagulation proteases can modulate intracellular signaling events by activating a subfamily of G-protein coupled receptors named protease-activated receptors (PARs) expressed on the cell surface of various organs. In vitro studies have indicated that while activated protein C (APC) in complex with endothelial protein C receptor (EPCR) elicits anti-inflammatory responses via activation of PAR1, thrombin elicits proinflammatory responses via the activation of the same receptor. We have provided some insight into the basis for this paradoxical effect by these proteases and showed that activation of PAR1 by thrombin can also elicit protective cellular responses if EPCR is occupied by the Gla-domain of protein C. Thus, we demonstrated that the occupancy of EPCR by protein C switches the PAR1 signaling specificity of thrombin from a proinflammatory to an anti-inflammatory response. Recent data indicates that a �rrestin2-dependent biased PAR1 signaling accounts for the protective signaling of APC. We hypothesize that occupancy of EPCR induces �arrestin2 biased PAR1 signaling independent of the protease activating PAR1. In a recent study, we also demonstrated that APC inhibits the secretion and proinflammatory signaling of high mobility group box 1 (HMGB1) protein in endothelial cells through activation of PAR1. We further demonstrated inorganic polyphosphate (similar to the size in platelets) dramatically up-regulates proinflammatory signaling responses of HMGB1 though interaction with receptor for advanced glycation end products (RAGE) and the purinergic P2Y1 receptor. In an in vivo study, we investigated the mechanism of the cytoprotective activity of APC in an ischemia/reperfusion (I/R) injury model and showed that APC elicits a cardioprotective response through activation of the AMPK signaling during I/R. Further studies revealed that APC inhibits production of reactive oxygen species (ROS) in cardiac tissues. Based on our preliminary data, we hypothesize that EPCR/PAR1 dependent signaling by APC results in epigenetic regulation and suppression of the proinflammatory, redox modulating protein, p66shc, thereby inhibiting ROS-mediated cellular injury. We also hypothesize that APC, through epigenetic regulation, down- regulates HMGB1 release, which has emerged as a key nuclear cytokine involved in the pathogenesis of inflammatory disorders including severe sepsis. We propose to investigate these important questions in four Specific Aims: Aim 1 will investigate the mechanism by which the activation of PAR1 by APC and thrombin elicits paradoxical signaling responses in endothelial cells. Aim 2 will investigate the mechanism by which polyphosphate (by itself or in complex with HMGB1) elicits proinflammatory signaling responses that are counteracted by APC. Aim 3 will investigate the mechanism of the protective activity of APC in a mouse model of injury-mediated peritoneal adhesion band formation. Aim 4 will investigate the mechanism by which the APC activation of AMPK limits cardiac damage caused by ischemia and reperfusion injury.

描述（由申请人提供）： 凝血蛋白酶可以通过激活在各种器官的细胞表面上表达的称为蛋白酶激活受体（PAR）的G蛋白偶联受体亚家族来调节细胞内信号转导事件。 C (APC) 与内皮蛋白 C 受体 (EPCR) 形成复合物，通过激活 PAR1 引发抗炎反应，凝血酶通过激活 PAR1 引发促炎反应我们已经对这些蛋白酶的这种矛盾效应的基础提供了一些见解，并表明了 如果 EPCR 被蛋白 C 的 Gla 结构域占据，凝血酶的 PAR1 也可以引发保护性细胞反应。因此，我们证明，蛋白 C 占据 EPCR 将凝血酶的 PAR1 信号传导特异性从促炎反应转变为抗炎反应最近的数据表明，依赖于 arrestin2 的偏向 PAR1 信号传导解释了 APC 的保护性信号传导，我们发现 EPCR 的占据会诱导 arrestin2 偏向。 PAR1 信号传导独立于激活 PAR1 的蛋白酶，在最近的一项研究中，我们还证明 APC 通过激活 PAR1 来抑制内皮细胞中高迁移率族蛋白 1 (HMGB1) 的分泌和促炎信号传导。通过与晚期糖基化终末产物 (RAGE) 受体和嘌呤能受体相互作用，显着上调 HMGB1 的促炎信号反应P2Y1 受体。在一项体内研究中，我们研究了 APC 在缺血/再灌注 (I/R) 损伤模型中的细胞保护活性机制，并表明 APC 通过在 I/R 过程中激活 AMPK 信号传导来引发心脏保护反应。进一步的研究表明，APC 抑制心脏组织中活性氧 (ROS) 的产生。根据我们的初步数据，我们发现 APC 的 EPCR/PAR1 依赖性信号传导会导致表观遗传调节和促炎性氧化还原的抑制。我们还发现，APC 通过表观遗传调节下调 HMGB1 的释放，而 HMGB1 已成为参与炎症性疾病（包括严重脓毒症）发病机制的关键核细胞因子。在四个具体目标中研究这些重要问题：目标 1 将研究 APC 和凝血酶激活 PAR1 在内皮细胞中引发矛盾信号反应的机制。将研究多磷酸盐（单独或与 HMGB1 复合）引发 APC 抵消的促炎信号反应的机制。目标 3 将研究 APC 在损伤介导的腹膜粘连带形成的小鼠模型中的保护活性机制。目标 4 将研究 AMPK 的 APC 激活限制缺血和再灌注损伤引起的心脏损伤的机制。