Convergence of the COX-2 and 5-lipoxygenase pathways

COX-2 和 5-脂氧合酶途径的融合

基本信息

批准号：
7541465
负责人：
Claus Schneider
金额：
$ 29.17万
依托单位：
VANDERBILT UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-01-01 至 2011-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7541465
关键词：
Active Sites Anabolism Anti-Inflammatory Agents Anti-inflammatory Arachidonate 5-Lipoxygenase Arachidonic Acids Arterial Fatty Streak Aspirin Asthma Atherosclerosis Attenuated Binding Binding Sites Biological Process Biology Carbon Cells Commit DNA Sequence Rearrangement Detection Dinoprostone Disease Eicosanoids Endothelial Cells Enzymatic Biochemistry Enzymes Etiology Family Genetic Crossing Over Human Hydrogen Peroxide Hydroxyeicosatetraenoic Acids Inflammation Inflammatory Inflammatory Response Interleukin-8 Isoenzymes Kinetics Lead Leukotriene A4 Leukotrienes Light Link Lipoxins Lipoxygenase Lung Malignant Neoplasms Mediating Mediator of activation protein Metabolism Mus Pathway interactions Peritoneal Macrophages Peroxides Pharmaceutical Preparations Property Prostaglandin D2 Prostaglandin H2 Prostaglandin-Endoperoxide Synthase Prostaglandins Psoriasis Reaction Regulation Resolution Route Series Signal Pathway Single Parent Substrate Specificity Testing Tissues Treatment Protocols analog angiogenesis arachidonic acid 5-hydroperoxide base cancer type cyclooxygenase 1 cyclooxygenase 2 macrophage mast cell novel novel therapeutics

项目摘要

There is strong evidence for the induction of the inflammatory enzymes 5-lipoxygenase (5-LOX) and cyclooxygenase-2 (COX-2) in atherosclerosis, asthma, and many types of cancer. Both enzymes mediate the inflammatory response of these diseases through the synthesis of leukotrienes and prostaglandins, respectively. The leukotriene and prostaglandin pathways have traditionally been viewed as independent biosynthetic routes since the committed step toward either pathway is taken as the initial oxygenation of the common substrate, arachidonic acid. This proposal is based on the finding that the 5-LOX product, 5S- hydroxyeicosatetraenoic acid (5S-HETE), is a selective and highly efficient substrate for oxygenation by COX-2 (but not by the COX-1 isozyme). The discovery of this novel substrate for COX-2 intimately links the two eicosanoid pathways. The common 5-LOX/COX-2 product is a novel di-endoperoxide that is structurally reminiscent of, but distinctly different from prostaglandin H2. In the first Specific Aim we propose to analyze the enzymology of the conversion of arachidonic acid into the novel di-endoperoxide by establishing the reaction kinetics, substrate specificity, and the structural basis for binding of 5-HETE in the COX-2 active site. The enzymatic transformation of the di-endoperoxide product will be studied using RAW264.7 cells and murine peritoneal macrophages, prototypical cells that expresses both 5-LOX and COX-2. Endogenous formation of the novel eicosanoid and its family of metabolites will be assessed in mouse atherosclerotic tissue. We will test the hypothesis that the novel di-endoperoxide (or its metabolites) possess anti- inflammatory properties. Preliminary studies have shown that the di-endoperoxide attenuates the release of interleukin-8 from stimulated mast cells and microvascular endothelial cells. The signaling pathways involved in this interaction will be studied using the 5-LOX and COX-2 expressing HMC-1 human mast cell. Characterization of the novel 5-LOX/COX-2 cross-over pathway will undoubtedly lead to an entirely new understanding of the biology of 5-LOX and COX-2, and it will also shed new light on the etiology and regulation of the inflammatory component of diseases like atherosclerosis, asthma, and cancer. These studies could ultimately lead to new therapeutic regimens for the treatment of these diseases using established anti-inflammatory medications.

有强有力的证据表明可诱导炎症酶 5-脂氧合酶 (5-LOX) 和环氧合酶-2 (COX-2) 与动脉粥样硬化、哮喘和多种癌症有关。两种酶均介导这些疾病通过白三烯和前列腺素的合成产生炎症反应，分别。白三烯和前列腺素途径传统上被视为独立的生物合成途径，因为任一途径的关键步骤被视为初始氧合常见底物，花生四烯酸。该提案基于 5-LOX 产品 5S- 羟基二十碳四烯酸 (5S-HETE) 是一种选择性且高效的氧化底物 COX-2（但不是由 COX-1 同工酶）。 COX-2 这种新型底物的发现与两条类二十烷酸途径。常见的 5-LOX/COX-2 产品是一种新型二内过氧化物，其结构为让人想起前列腺素 H2，但又明显不同。在第一个具体目标中，我们建议分析通过建立以下条件，将花生四烯酸转化为新型二内过氧化物的酶学反应动力学、底物特异性以及 COX-2 活性物质中 5-HETE 结合的结构基础地点。将使用 RAW264.7 细胞研究二内过氧化物产物的酶促转化鼠腹膜巨噬细胞，表达 5-LOX 和 COX-2 的典型细胞。内源性将在小鼠动脉粥样硬化中评估新型类二十烷酸及其代谢物家族的形成组织。我们将检验以下假设：新型二内过氧化物（或其代谢物）具有抗- 炎症特性。初步研究表明，二内过氧化物会减弱来自刺激的肥大细胞和微血管内皮细胞的白介素-8。涉及的信号通路将使用表达 5-LOX 和 COX-2 的 HMC-1 人类肥大细胞来研究这种相互作用。新型 5-LOX/COX-2 交叉途径的表征无疑将带来全新的结果了解 5-LOX 和 COX-2 的生物学，也将为病因学和调节动脉粥样硬化、哮喘和癌症等疾病的炎症成分。这些研究最终可能会产生治疗这些疾病的新治疗方案已确定抗炎药物。