Cytochrome P450 Derived Eicosanoids and Inflammation

摘要： 炎症是一个基本的过程，在许多疾病的发病机制中起着不可或缺的作用。 人类的状态。核因子-kappaB是炎症反应的中枢介质，通过 转录激活细胞因子、趋化因子和细胞黏附分子的表达。因此， 确定旨在抑制这一病理过程的新策略提供了实质性的治疗 潜力。花生四烯酸是由细胞色素P450(CYP)环氧合酶氧化代谢的。 肝脏和肝外组织中的环氧二十碳三烯酸(EETs)的亚家族。这个 EETs被可溶性环氧化物水解酶(SEH)迅速水解为活性较低的二羟基二十碳三烯酸 (DHETs)。花生四烯酸也被CYP-代谢为20-羟基二十碳四烯酸(20-HETE)。 来自细胞色素P4A和细胞色素P4F亚家族的羟基酶。最近的证据表明，CYP派生的 EETs和20-HETE分别具有抗炎和促炎作用。然而，中国的贡献 CYP介导的二十烷基糖代谢对体内炎症的调节还不是很严格 特色化的。我们假设CYP环氧合酶-和CYP-之间的功能平衡- 羟基酶介导的花生四烯酸代谢在核因子-B介导的调节中是不可或缺的 体内的炎症反应以及这种平衡的调节有利于CYP环氧合酶途径 提供了巨大的治疗潜力。本提案的主要目标是：(1)界定 肝脏和肝外CYP介导的二十烷类化合物代谢的炎症反应，(2)定义 环氧合酶介导的EET生物合成和sEH介导的EET水解酶在细胞周期中的作用 炎症的调节，以及(3)表征CYP环氧合酶和CYP的相对影响。 羟基酶途径对体内炎症反应的调控。该项目将利用新的转基因技术 和基因敲除小鼠以及在体内操纵CYP介导的二十烷类代谢的药理学工具， 同时利用已建立的分子生物学和分子生物学来表征核因子-B介导的炎症反应 分析技术。总的来说，这一系列新颖的实验将定义 环氧合酶衍生的EETs和羟基酶衍生的20-HETE对肝脏和肝脏的调节作用 体内肝外炎症反应，并促进新型抗炎药物的研制 对人类多种疾病状态具有潜在治疗应用的策略。

ABSTRACT: Inflammation is a fundamental process which plays an integral role in the pathogenesis of numerous disease states in humans. Nuclear factor kappa B (NF-¿B) is a central mediator of the inflammatory response via transcriptional activation of cytokine, chemokine and cellular adhesion molecule expression. Consequently, identification of novel strategies aimed at inhibition of this pathological process offers substantial therapeutic potential. Arachidonic acid is oxidatively metabolized by cytochrome P450 (CYP) epoxygenases from the CYP2J and CYP2C subfamilies to epoxyeicosatrienoic acids (EETs) in hepatic and extra-hepatic tissue. The EETs are rapidly hydrolyzed by soluble epoxide hydrolase (sEH) to less active dihydroxyeicosatrienoic acids (DHETs). Arachidonic acid is also metabolized to 20-hydroxyeicosatetraenoic acid (20-HETE) by CYP ¿- hydroxylases from the CYP4A and CYP4F subfamilies. Recent evidence has demonstrated that CYP-derived EETs and 20-HETE possess anti- and pro-inflammatory effects, respectively. However, the contribution of CYP-mediated eicosanoid metabolism to the regulation of inflammation in vivo has not been rigorously characterized. We hypothesize that the functional balance between CYP epoxygenase- and CYP ¿- hydroxylase-mediated arachidonic acid metabolism is integral to the regulation of NF-¿B-mediated inflammatory responses in vivo, and modulation of this balance in favor of the CYP epoxygenase pathway offers substantial therapeutic potential. The primary objectives of this proposal are to: (1) define the impact of the inflammatory response on hepatic and extra-hepatic CYP-mediated eicosanoid metabolism, (2) define the functional role of CYP epoxygenase-mediated EET biosynthesis and sEH-mediated EET hydrolysis in the regulation of inflammation, and (3) characterize the relative impact of CYP epoxygenase and CYP ¿- hydroxylase pathway modulation on inflammatory responses in vivo. This project will utilize novel transgenic and knock-out mice and pharmacological tools to manipulate CYP-mediated eicosanoid metabolism in vivo, while characterizing NF-¿B-mediated inflammatory responses using established molecular biology and analytical techniques. Collectively, this series of novel experiments will define the mechanistic contribution of CYP epoxygenase-derived EETs and CYP ¿-hydroxylase-derived 20-HETE to the regulation of hepatic and extra-hepatic inflammatory responses in vivo, and facilitate the development of new anti-inflammatory strategies with potential therapeutic application to numerous disease states in humans.