Identification of allosteric molecules for DOR-KOR heteromer-mediated peripheral analgesia

DOR-KOR 异聚体介导的外周镇痛变构分子的鉴定

基本信息

批准号：
10608439
负责人：
WILLIAM P CLARKE
金额：
$ 55.78万
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：
2023
资助国家：
美国
起止时间：
2023-09-01 至 2028-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10608439
关键词：
Absence of pain sensation Adult Adverse effects Afferent Neurons Affinity Agonist Analgesics Binding COVID-19 pandemic Cells Chemicals Clinical Dangerousness Data Dependence Development Effectiveness Future G-Protein-Coupled Receptors Human Resources In Vitro Injections Lead Libraries Life Ligands Local Anesthetics Mediating Motor Neurons Nociception Nociceptors Opioid Opioid Analgesics Opioid Receptor Pain Pain management Penetrance Peripheral Persons Pharmaceutical Preparations Phase Physiological Property Protomer Rattus Reporting Sensory Series Structure Structure-Activity Relationship System Testing Therapeutic Toxicology Training United States National Institutes of Health Ventilatory Depression addiction antagonist antinociception chronic pain collaborative approach daily pain delta opioid receptor design drug-like compound effective therapy efficacy evaluation experience high throughput screening in silico in vivo kappa opioid receptors mu opioid receptors neurotransmission novel opioid epidemic peripheral pain programs receptor research clinical testing screening small molecule libraries

项目摘要

Current clinically prescribed analgesics target mu opioid receptors within the CNS and can produce dangerous and often lethal adverse effects, including respiratory depression and addiction. Importantly, these analgesics are principally responsible for precipitating the opioid crisis, which has only worsened with the SARS- CoV-2 pandemic. Thus, alternative approaches for treatment of pain are badly needed. As evidenced by the efficacy of local anesthetics, a promising approach to treat pain is to inhibit peripheral pain-sensing neurons (nociceptors) that mediate pain neurotransmission. We have found that delta opioid receptor (DOR)-kappa opioid receptor (KOR) heteromers are expressed and when activated produce strong and sustained antinociception. Thus, the DOR-KOR heteromer may be a promising target for development of peripherally-restricted analgesic drugs to treat nociceptive pain. In this application, we propose a multifaceted and highly collaborative approach to identify small, drug-like molecules that selectively activate the DOR-KOR heteromer expressed by nociceptors. Our approach to develop drugs that selectively activate the DOR-KOR heteromer is to take advantage of a unique property of GPCR heteromers – interprotomer allosterism. Interprotomer allosterism is where an orthosteric ligand for one of the protomers in the heteromeric pair allosterically alters the affinity and/or intrinsic efficacy of the orthosteric ligand for the other protomer. We have demonstrated that such interprotomer allosterism occurs for ligands acting at the DOR-KOR heteromer. Moreover, we have identified one ligand, 6’- GNTI, that is an antagonist at both DOR and KOR in nociceptors, but via interprotomer allosterism, selectively activates the DOR-KOR heteromer resulting in strong antinociception. Here we will take advantage of this inter- protomer allosterism to identify novel heteromer-selective compounds. The Specific Aims of this project are to identify novel DOR-KOR heteromer ligands using 1) a synthetic strategy based on structurally diverse chemical series; 2) high-throughput screening (HTS) of chemical libraries of drug-like compounds; and 3) structure-based in-silico screening of libraries of commercially-available chemical compounds. Hits will be initially identified using HEK cell expression systems. Potential candidate compounds that emerge from the in vitro screens will undergo ADME and receptor selectivity screening. Suitable compounds will then be screened for peripherally-mediated antinociceptive efficacy mediated by the DOR-KOR heteromer in nociceptors in rats. Compounds that emerge from this project (we expect ~5 compounds) will undergo further development using the NIH BPN UG3/UH3 program to advance candidates through IND-enabling toxicology and phase 1 clinical testing for safer and effective treatment of pain. We also will have obtained valuable structure-activity relationship information about the identified DOR and KOR ligands that will aid in the future design of DOR, KOR and DOR-KOR heteromer ligands. Successful application of this approach (interprotomer allosterism) could be applied for other GPCR heteromers to help further our understanding of the function of heteromers in physiological systems.

目前临床处方的镇痛药以中枢神经系统内的μ阿片受体为目标，可以产生危险且往往致命的不良反应，包括呼吸抑制和成瘾。镇痛药是引发阿片类药物危机的主要原因，而这种危机随着 SARS 的爆发而进一步恶化。因此，迫切需要治疗疼痛的替代方法。局麻药的功效，一种有前途的治疗疼痛的方法是抑制外周痛觉神经元（伤害感受器）介导疼痛神经传递我们发现 δ 阿片受体 (DOR)-kappa 阿片类药物。受体（KOR）异聚体被表达，并在激活时产生强烈且持续的抗伤害作用。因此，DOR-KOR 异聚体可能是开发外周限制性药物的一个有希望的靶标。在此应用中，我们提出了一种多方面且高度协作的镇痛药物来治疗伤害性疼痛。方法识别通过表达选择性激活 DOR-KOR 异聚体的药物样小分子我们开发选择性激活 DOR-KOR 异聚体的药物的方法是采用 GPCR 异聚体的独特性质的优势 - 原体间变构现象是。其中异聚体对中的原聚体之一的正构配体以变构方式改变亲和力和/或我们已经证明了这种原体间的正位配体的内在功效。作用于 DOR-KOR 异聚体的配体会发生变构现象，此外，我们还鉴定了一种配体，6'-。 GNTI，是伤害感受器中 DOR 和 KOR 的拮抗剂，但通过原体间变构作用，选择性地激活 DOR-KOR 异聚体，产生强烈的抗伤害作用。在这里，我们将利用这种相互作用。原体变构作用来鉴定新型异聚体选择性化合物该项目的具体目标是使用 1) 基于结构多样化化学物质的合成策略来识别新型 DOR-KOR 异聚体配体 2）类药化合物化学库的高通量筛选（HTS）；3）基于结构的化合物；将使用计算机对市售化合物库进行初步筛选。 HEK 细胞表达系统将经历体外筛选的潜在候选化合物。然后将筛选外周介导的 ADME 和受体选择性筛选。大鼠伤害感受器中 DOR-KOR 异聚体介导的镇痛功效。该项目中的化合物（我们预计约 5 种化合物）将使用 NIH BPN UG3/UH3 进行进一步开发计划通过支持 IND 的毒理学和 1 期临床测试来推进候选人的发展，以实现更安全和更安全我们还将获得有关疼痛的有效结构与活动关系的信息。确定的 DOR 和 KOR 配体将有助于 DOR、KOR 和 DOR-KOR 异聚体的未来设计这种方法（原体间变构）的成功应用可以应用于其他 GPCR。异聚体有助于进一步了解异聚体在生理系统中的功能。