A transgenic model of opioid tolerance and drug discovery

 描述（由申请人提供）：阿片类药物是医学上使用最广泛的镇痛药，也是一些最广泛滥用的物质。对阿片类药物的耐受性是一个主要的医学问题，导致这些化合物治疗慢性疼痛的功效降低，并增加成瘾和滥用的可能性。在这项提案中，我们详细介绍了一种创新的，潜在的变革性方法，以揭示阿片类药物耐受性机制的见解，并建议开发一个人源化的转基因平台，用于发现阻断或减少耐受性的小分子。我们的方法旨在找到阻断耐受性的药物和药物靶点，从而大大提高现有畅销药物的疗效。阻止或减少对阿片类药物的耐受性也将是预防依赖的重要一步。 我们建议使用线虫C. elegans，作为研究G蛋白偶联受体（GPCR）信号传导的遗传模型系统，该受体介导对阿片类药物的镇痛和成瘾反应，即μ-阿片受体（莫尔）。我们将产生转基因C。表达人类莫尔并对阿片类药物刺激产生行为变化的线虫。通过使用一系列的细胞特异性启动子，我们建议分析两种主要类型的行为：化学感觉和运动。此外，我们还将开发试验来研究长期暴露于莫尔激动剂引起的行为耐受性。在这项提案中，我们的目标是开发一个人源化的转基因平台，以研究阿片类药物诱导的耐受性，并有可能对耐受性及其化学衰减的机制提供显着和公正的见解。因为我们的提议让生物体的生物学为耐受性问题提供了解决方案，所以我们的方法比以前的努力取得了重大进展，这些努力专注于使用基于细胞的测定的特定分子靶点，不幸的是，这些测定的成功有限。C. elegans和我们建议开发的测定的可扩展性在哺乳动物或脊椎动物的整个生物体系统中是根本不可能的，这进一步支持了我们对模型系统的选择。 我们的建议的成功实施有可能改变药物成瘾的研究方式。这一提议的成功实施将为发现新的小分子和耐受性调节基因奠定基础。我们工作的成功将促进人源化C语言的发展。elegans的高通量行为平台，用于许多其他成瘾目标，包括可卡因，甲基苯丙胺和尼古丁。

 DESCRIPTION (provided by applicant): Opioid drugs are the most widely used analgesics in medicine, and are also some of the most widely abused substances. Tolerance to opioids is a major medical problem resulting in reduced efficacy of these compounds for treatment of chronic pain, and increasing the potential for addiction and abuse. In this proposal, we detail an innovative, potentially transformative approach to reveal insight into the mechanisms of opioid tolerance, and propose to develop a humanized, transgenic platform for discovery of small molecules that block or reduce tolerance. Our approach aims to find drugs and drug targets that block tolerance, thereby greatly increasing the efficacy of existing blockbuster pharmaceuticals. Blocking or reducing tolerance to opioids would also be a major step towards preventing dependence. We propose to use the nematode, C. elegans, as a genetic model system to study signaling by a G protein coupled receptor (GPCR) that mediates analgesic and addictive responses to opioids, the µ-opioid receptor (MOR). We will generate transgenic C. elegans that express human MOR and respond to its stimulation by opioids with behavioral changes. By using a series of cell-specific promoters, we propose to analyze two major types of behavior: chemosensation and locomotion. Further, we will develop assays to study behavioral tolerance caused by prolonged exposure to MOR agonists. In this proposal, we take aim at developing a humanized, transgenic platform to study opioid-induced tolerance with the potential to provide significant and unbiased insight into the mechanisms of tolerance and its chemical attenuation. Because our proposal lets the biology of a living organism provide a solution to the problem of tolerance, our approach is a significant advance over previous efforts that have focused on specific molecular targets using cell-based assays that have, unfortunately, had limited success. The microscopic size of C. elegans and the scalability of the assays we propose to develop are simply not possible in mammalian or vertebrate whole organismal systems further supporting our choice of model system. The successful implementation of our proposal has the potential to be transformative to how drug addiction is studied. Successful implementation of this proposal will lay the ground for the discovery of novel small molecules and genes that regulator of tolerance. The success of our work will encourage the development of humanized C. elegans high throughput behavioral platforms for many other addiction targets including cocaine, methamphetamine, and nicotine.