Evaluation of Endogenous TRP Agonists in Human Burns

内源性 TRP 激动剂在人体烧伤中的评价

• 批准号: 8631316
• 负责人: Kenneth M Hargreaves
• 金额: $ 29.53万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-01 至 2017-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8631316
• 关键词: Acute; Address; Adverse effects; Afferent Neurons; Agonist; Analgesics; Arachidonic Acids; Blood capillaries; Burn injury; Burning Pain; Chemicals; Clinical; Coupled; Cytochrome P450; Cytochromes; Data; Databases; Development; Electrophysiology (science); Enzymes; Evaluation; Family member; Figs - dietary; Gated Ion Channel; Grant; Heating; High Pressure Liquid Chromatography; Hospitalization; Human; Hyperalgesia; In Vitro; Injection of therapeutic agent; Injury; Knowledge; Lead; Ligands; Light; Linoleic Acids; Lipids; Lipoxygenase; Mechanics; Medical; National Institute of General Medical Sciences; Neurons; Nociception; Nociceptors; Pain; Pain management; Patients; Peripheral; Persistent pain; Pharmaceutical Preparations; Production; Rattus; Reporting; Research; Risk; Site; Skin; Source; Stimulus; System; Testing; Thermal Hyperalgesias; Time; Tissues; Transcript; V1 Receptors; adverse outcome; allodynia; base; capillary; design; detector; in vitro Model; in vivo; innovation; liquid chromatography mass spectrometry; millisecond; novel; novel therapeutic intervention; oxidized lipid; pain receptor; patch clamp; preclinical study; public health relevance; receptor; response; spontaneous pain

Abstract: Evaluation of Endogenous TRP Agonists in Human Burns Burns often lead to persistent pain not well managed by available analgesics. The mechanisms of burn pain are incompletely understood. However, t h e TRPV1 (transient receptor potential V1) receptor appears to be pivotally involved in post-burn pain. In our preliminary data, ~67% of post-burn thermal hyperalgesia is blocked by peripheral injection of a TRPV1 receptor antagonist. In addition, extracts of burned human skin produce thermal hyperalgesia when injected into rats via a TRPV1 receptor mechanism. These novel data suggest that TRPV1 significantly contributes to post-thermal burn injuries. Interestingly, the precise mechanism(s) for the activation of TRPV1 remains unknown. Converging evidence indicates that oxidized lipids derived from linoleic or arachidonic acid are released during tissue injury and activate TRPV1 and/or TRPA1, resulting in nociceptor depolarization and pain. Many of these lipids are formed by the actions of enzymes such as cytochrome P450s (CYP) or lipoxygenase (LOX). This is of particular significance since analysis of the GLUE Grant indicates that transcripts encoding these enzymes are elevated as early as 0-3 days after burns. Therefore, we propose the central hypothesis that oxidized lipids are enzymatically formed after human burn injuries and contribute to post-burn pain by activation of TRPV1 and/or TRPA1. The present Aims will: Specific Aim 1: Identify enzymes that oxidize linoleic acid to form metabolites that activate TRPV1 or TRPA1. We have analyzed the NIGMS-supported GLUE Grant microarray database of transcripts from skin with burn injury vs. control human skin and found significantly elevated levels of CYPs and LOXs that persist for up to 12 months. This Aim will use a COS expression system to evaluate whether these enzymes are capable of oxidizing linoleic acid into TRPV1 or TRPA1 agonists using patch clamp electrophysiology and determine the functional activity of these compounds in preclinical studies. Additional studies will evaluate possible entourage interactions among these lipids for activating TRP channels. Specific Aim 2: Identify enzymes that oxidize arachidonic acid to form metabolites that activate TRPV1 or TRPA1. Aim 2 will use the same approach as Aim 1, but will focus on arachidonic acid metabolites. This novel hypothesis has strong scientific and medical implications. From a scientific perspective, it expands the focus of TRPV1 from being a detector of transient heat, to a detector of oxidized lipids released from burned skin long after the heat-induced injury. From a medical perspective, this hypothesis is innovative since it leads to a fundamentally new pharmacological approach for treating burn pain - by blocking the enzymatic synthesis of TRPV1- and/or TRPA1-active compounds released from tissues after burns. The present proposal is designed to comprehensively test this potentially ground-breaking hypothesis of persistent post-burn pain.

翻译后摘要：在人类烧伤内源性TRP激动剂的评价 烧伤经常导致持续性疼痛，可用的止痛药不能很好地控制。烧伤的机制 疼痛是不完全理解的。然而，TRPV1（瞬时受体电位V1）受体出现， 与烧伤后疼痛密切相关在我们的初步数据中，约67%的烧伤后热痛觉过敏是由 通过外周注射TRPV1受体拮抗剂阻断。此外，烧伤人皮肤的提取物 当通过TRPV1受体机制注射到大鼠中时产生热痛觉过敏。这些新数据 表明TRPV1显著促进热烧伤后损伤。有趣的是， TRPV1的激活机制仍然未知。有证据表明 衍生自亚油酸或花生四烯酸的脂质在组织损伤期间释放并激活TRPV 1和/或 TRPA1，导致伤害感受器去极化和疼痛。这些脂质中的许多是由以下作用形成的： 酶，如细胞色素P450（CYP）或脂氧合酶（LOX）。这一点特别重要，因为 对GLUE Grant的分析表明，编码这些酶的转录本早在0 - 3 烧伤后几天因此，我们提出了一个中心假设，即氧化脂质是酶促的， 在人烧伤后形成，并通过激活TRPV1和/或 TRPA 1.目前的目标是： 具体目标1：确定氧化亚油酸形成激活TRPV1或TRPA1的代谢物的酶。 我们分析了NIGMS支持的GLUE Grant微阵列数据库中来自烧伤皮肤的转录本 损伤与对照人类皮肤相比，发现CYP和LOX水平显著升高，持续长达12 个月该目的将使用COS表达系统来评估这些酶是否能够 使用膜片钳电生理学将亚油酸氧化成TRPV1或TRPA1激动剂，并确定 这些化合物在临床前研究中的功能活性。进一步的研究将评估可能的随行人员 这些脂质之间的相互作用用于激活TRP通道。 具体目标2：鉴定氧化花生四烯酸以形成激活TRPV 1或TRPV 2的代谢物的酶。 TRPA 1.目标2将使用与目标1相同的方法，但将侧重于花生四烯酸代谢物。 这一新的假设具有很强的科学和医学意义。从科学的角度来看， TRPV 1的重点从作为瞬态热的检测器，到从释放的氧化脂质的检测器， 烧伤皮肤后很长一段时间的热诱导损伤。从医学的角度来看，这一假设是创新的，因为 它为治疗烧伤疼痛提供了一种全新的药理学方法--通过阻断 烧伤后从组织释放的TRPV1和/或TRPA1活性化合物的合成。现时的建议 旨在全面测试这一潜在的突破性假设的持续烧伤后疼痛。