Evaluation of Endogenous TRP Agonists in Human Burns

内源性 TRP 激动剂在人体烧伤中的评价

基本信息

批准号：
9178073
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
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-01-01 至 2018-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9178073
关键词：
Acute Address Adverse effects Afferent Neurons Agonist Analgesics Arachidonic Acids Blood capillaries Burn injury Chemicals Clinical Coupled Cytochrome P450 Cytochromes Data Databases Development Electrophysiology (science)Enzymes Evaluation Family member Gated Ion Channel Grant High Pressure Liquid Chromatography Hospitalization Human Hyperalgesia In Vitro Injectable Injection of therapeutic agent Injury Ion Channel Gating Knowledge Lead Ligands Light Linoleic Acids Lipids Lipoxygenase Mass Spectrum Analysis Mechanics Medical National Institute of General Medical Sciences Neurons Nociception Nociceptors Oxides Pain Pain management Patients Peripheral Persistent pain Pharmaceutical Preparations Pharmacology Production Rattus Reporting Research Risk Site Skin Source Stimulus System TRPV1 gene Testing Thermal Hyperalgesias Time Tissues Transcript V1 Receptors adverse outcome allodynia base capillary design detector in vitro Model in vivo innovation millisecond novel novel therapeutic intervention oxidized lipid pain receptor patch clamp preclinical study public health relevance receptor response spontaneous pain

项目摘要

DESCRIPTION (provided by applicant): Burns often lead to persistent pain not well managed by available analgesics. The mechanisms of burn pain are incompletely understood. However, the 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.

描述（由申请人提供）：烧伤通常会导致持续性疼痛无法通过可用的镇痛药来管理。烧伤疼痛的机制尚不完全理解。但是，TRPV1（瞬态受体电位V1）受体似乎与燃烧后疼痛有关。在我们的初步数据中，约有67％的燃烧后热痛觉过敏被TRPV1受体拮抗剂的外周注射阻断。此外，当通过TRPV1受体机制注入大鼠时，燃烧的人皮的提取物会产生热痛觉过敏。这些新的数据表明，TRPV1显着有助于烧伤后烧伤。有趣的是，TRPV1激活的精确机制仍然未知。融合的证据表明，在组织损伤过程中释放出源自亚油酸或蛛网膜酸的氧化脂质并激活TRPV1和/或TRPA1，从而导致伤害感受器的去极化和疼痛。这些脂质中的许多是由酶（例如细胞色素p450s（CYP）或脂氧合酶（LOX））的作用形成的。这是特别重要的，因为对胶水赠款的分析表明，编码这些酶的转录本早在燃烧后0-3天就升高。因此，我们提出了一个中心假设，即在人体烧伤后氧化脂质是酶促形成的，并通过激活TRPV1和/或TRPA1导致燃烧后疼痛。目前的目的将：特定目标1：确定氧化亚油酸以形成激活TRPV1或TRPA1的代谢产物的酶。我们已经分析了NIGMS支持的胶水赠款授予的微阵列数据库，这些数据库具有烧伤损伤与控制人皮肤的皮肤的转录本，发现CYP和LOX水平显着升高，可持续使用长达12个月。该目标将使用COS表达系统来评估这些酶是否能够使用斑块夹电生理学将亚油酸氧化为TRPV1或TRPA1激动剂，并确定这些化合物在临时性研究中的功能活性。其他研究将评估这些脂质之间可能的随行相互作用以激活TRP通道。特定目标2：鉴定氧化蛛网膜酸以形成激活TRPV1或TRPA1的代谢产物。 AIM 2将使用与AIM 1相同的方法，但将专注于花生四烯酸代谢产物。这个新颖的假设具有强烈的科学和医学意义。从科学的角度来看，它将TRPV1的重点从作为瞬态热的检测器扩展到了热诱导损伤后很长时间从燃烧的皮肤释放的氧化脂质的检测器。从医学的角度来看，该假设具有创新性，因为它通过阻止TRPV1-和/或TRPA1-Active化合物的酶促合成从组织中释放出来，从而导致一种从根本上进行治疗烧伤疼痛的新药理方法。本提案旨在全面测试持续燃烧后疼痛的潜在开创性假设。