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（由适用提供）：凝血蛋白可以通过激活在各种器官的细胞表面表达的名为蛋白激活受体（PARS）的G蛋白偶联受体的亚家族来调节细胞内信号传导事件。体外研究表明，虽然与内皮蛋白C受体（EPCR）复合激活蛋白C（APC），通过激活PAR1激活通过激活同一受体引起促炎反应，从而引起抗炎反应。我们为这些蛋白酶提供了对这种矛盾作用的基础的一些见解，并表明激活的激活 如果蛋白质的GLA膜占据EPCR占据EPCR，凝血酶的PAR1也会引起受保护的细胞反应。这证明，蛋白C占EPCR的占用率从促炎性转变为抗炎反应的蛋白C的PAR1信号传导特异性。最近的数据表明，RRESTIN2依赖性偏置PAR1信号传导解释了APC的受保护信号。我们假设EPCR的占用率诱导抑制素2的PAR1信号传导，而与蛋白质激活PAR1无关。在最近的一项研究中，我们还证明了APC通过激活PAR1抑制了内皮细胞中高迁移率组1（HMGB1）蛋白的分泌和促炎信号传导。我们进一步证明了无机多磷酸盐（类似于血小板的大小），大大上调了HMGB1的促炎信号传导反应，尽管与受体相互作用用于晚期糖基化最终产物（RAGE）和嘌呤能P2Y1受体。在一项体内研究中，我们研究了缺血/再灌注（I/R）损伤模型中APC细胞保护活性的机制，并表明APC通过激活I/R期间的AMPK信号引起心脏保护反应。进一步的研究表明，APC抑制心脏组织中活性氧（ROS）的产生。基于我们的初步数据，我们假设APC取决于EPCR/PAR1信号导致表观遗传调节和抑制促炎，氧化还原调节蛋白P66SHC的抑制，从而抑制ROS ROS介导的细胞损伤。我们还假设APC通过表观遗传调节下调HMGB1释放，这已成为参与包括严重败血症在内的炎性疾病发病机理的关键核细胞因子。我们建议在四个特定目标中研究这些重要问题：AIM 1将研究APC和凝血酶在内皮细胞中引起pAR1激活的机制。 AIM 2将研究多磷酸本身（本身或与HMGB1复合物）引发APC抵消的促炎信号反应的机制。 AIM 3将研究APC在损伤介导的腹膜广告带形成的小鼠模型中的保护活性的机制。 AIM 4将研究APC激活AMPK限制由缺血和再灌注损伤引起的心脏损伤的机制。