Targeting GPCRs in amygdalar and cortical neural ensembles to treat pain aversion

靶向杏仁核和皮质神经群中的 GPCR 来治疗疼痛厌恶

基本信息

批准号：
10055582
负责人：
Gregory Scherrer
金额：
$ 280.29万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-15 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10055582
关键词：
Acute Pain Affect Affective Agonist American Amygdaloid structure Analgesics Animal Model Animals Anterior Anxiety Area Behavior Behavioral Assay Bioinformatics Brain Breathing Catalogs Cells Clinical Code Collaborations Complement Coupled Disease Drug Modulation Drug Targeting Electrophysiology (science)Emotional Emotions Fluorescence-Activated Cell Sorting Fluorescent in Situ Hybridization G-Protein-Coupled Receptors Genetic Genomics Human In Situ Hybridization Label Lateral Light Mechanics Mediating Mental Depression Methods Molecular Monitor Mus Neurons Nociception Opioid Opioid Analgesics Opioid Receptor Pain Pain quality Pathway interactions Patients Pattern Peripheral nerve injury Pharmaceutical Preparations Population Property Proteins Pyramidal Cells RNA Reflex action Reporting Research Rewards Rodent Role SSTR2 gene Safety Science Sensory Shapes Slice Somatostatin Receptor Stimulus Testing Tracer Translating Validation Viral Whole Body Plethysmography Wild Type Mouse Withdrawal allodynia base brain tissue cell cortex chronic pain chronic pain patient cingulate cortex cingulotomy comorbidity designer receptors exclusively activated by designer drugs dosage experience hippocampal pyramidal neuron human tissue imaging study in vivo in vivo imaging mouse genetics negative affect neural circuit neurophysiology novel novel therapeutics pain patient pain relief painful neuropathy promoter receptor relating to nervous system response reward processing side effect single-cell RNA sequencing spontaneous pain

项目摘要

PROJECT SUMMARY Pain is a multidimensional experience with sensory and affective components. The aversive quality of pain, i.e. its inherent unpleasantness, causes a majority of chronic pain patients’ suffering and often leads to comorbid disorders such as anxiety and depression. Despite their addictive qualities, opioid analgesics remain clinically useful since they can profoundly dampen pain affect. Thus, discovering targets that could alter neural activity selectively in neural circuits that generate pain aversion, but not in the reward or breathing circuits that opioids also alter, is an attractive strategy to develop novel, safer analgesics. Recently, by combining in vivo imaging and chemogenetic manipulations of neural dynamics in the basal and lateral amygdala (BLA) of freely behaving mice encountering noxious stimuli, our collaboration discovered a distinct neural ensemble in the BLA that encodes the negative affective valence of pain (Corder et al., Science, 2019). Chemogenetic inhibition of this nociceptive coding ensemble using Gi/o-protein-coupled-DREADDs alleviated pain affective behaviors without altering withdrawal reflexes, anxiety or reward. Moreover, our functional studies of this nociceptive ensemble revealed its causal role in the phenomenon of allodynia. Based on these exciting findings, we now seek to identify novel targets to treat pain by determining the molecular identity of these BLA nociceptive cells via in situ hybridization and single cell RNA-sequencing (scRNA-seq). Our preliminary scRNA-seq studies of BLA nociceptive cells suggest they express dozens of Gi/o protein-coupled receptors (Gi/o-GPCRs) that could be targeted for anti-nociception against pain affect. Further, our tracing studies have revealed a set of layer V pyramidal cells in anterior cingulate cortex (ACC) that project onto BLA nociceptive neurons, consistent with the fact cingulotomy can be used to treat intractable chronic pain. Resolving the molecular identity of these ACC nociceptive cells could also reveal new targets to treat pain affect. Thus, here we propose to catalog candidate Gi/o-GPCR targets in BLA and ACC (Aim 1, Discovery), test their utility to treat pain (Aim 2, Validation), and verify these new targets have no effect in the brain’s reward and breathing circuitry (Aim 3, Safety & Translatability). In Aim 1 we will identify Gi/o-GPCR targets in pain affect circuits of the BLA and ACC using mouse genetics, viral tracers, scRNA-seq and bioinformatics analyses. In Aim 2, we will validate the neurophysiological effects and analgesic properties of these new targets, using electrophysiological recordings in live brain tissue slices, animal models of acute and chronic pain, and Ca2+ imaging studies in behaving mice of BLA and ACC neural activity. In Aim 3, we will verify the safety and translatability of the novel antinociceptive drug targets. We will evaluate each target for abuse potential and effects on breathing by using behavioral assays for reward processing and whole-body plethysmography, respectively. To evaluate whether our results in rodents are likely to translate clinically, we will also analyze expression patterns of the drug targets in human tissue using in situ hybridization.

项目概要疼痛是一种具有感觉和情感成分的多维体验，即疼痛的厌恶性质。它固有的不愉快感，给大多数慢性疼痛患者带来痛苦，并常常导致合并症尽管阿片类镇痛药具有成瘾性，但其在临床上仍然存在。有用，因为它们可以极大地抑制疼痛影响，从而发现可以改变神经活动的目标。选择性地作用于产生疼痛厌恶的神经回路，但不作用于阿片类药物的奖赏或呼吸回路另一个改变是开发新型、更安全的镇痛药的一个有吸引力的策略。最近，通过结合体内成像和基础神经动力学的化学遗传学操作我们的合作发现，自由行为的小鼠遇到有害刺激时的杏仁核和外侧杏仁核（BLA） BLA 中的一个独特的神经系统编码了疼痛的负面情感效价（Corder 等人，Science， 2019）使用 Gi/o-蛋白偶联 DREADD 对这种伤害性编码整体进行化学遗传学抑制。减轻疼痛情感行为而不改变退缩反射、焦虑或奖励。对这种伤害感受整体的功能研究揭示了其在异常性疼痛现象中的因果作用。基于这些令人兴奋的发现，我们现在寻求通过确定治疗疼痛的新靶点通过原位杂交和单细胞 RNA 测序确定这些 BLA 伤害性细胞的分子身份 (scRNA-seq)。我们对 BLA 伤害感受细胞的初步 scRNA-seq 研究表明它们表达数十个 Gi/o。蛋白质偶联受体 (Gi/o-GPCR) 可以作为抗伤害感受的目标。我们的追踪研究揭示了前扣带皮层 (ACC) 中的一组 V 层锥体细胞作用于 BLA 伤害性神经元，这与扣带回切开术可用于治疗顽固性慢性疼痛的事实相一致。解析这些 ACC 伤害性细胞的分子身份还可以揭示治疗疼痛影响的新靶点。因此，在这里我们建议对 BLA 和 ACC 中的候选 Gi/o-GPCR 靶点进行编目（目标 1，发现），测试它们治疗疼痛的效用（目标 2，验证），并验证这些新目标对大脑的奖赏和奖励没有影响呼吸回路（目标 3，安全性和可翻译性）在目标 1 中，我们将确定疼痛影响中的 Gi/o-GPCR 目标。使用小鼠遗传学、病毒示踪剂、scRNA-seq 和生物信息学分析来分析 BLA 和 ACC 的电路。目标 2，我们将验证这些新靶标的神经生理学效应和镇痛特性，使用活体脑组织切片、急性和慢性疼痛动物模型以及 Ca2+ 的电生理记录在目标 3 中，我们将验证 BLA 和 ACC 神经活动的行为小鼠的安全性和有效性。我们将评估每个靶点的滥用潜力和可转化性。通过使用行为分析进行奖励处理和全身体积描记法对呼吸的影响，为了评估我们在啮齿动物身上的结果是否有可能转化为临床，我们还将进行分析。使用原位杂交研究药物靶标在人体组织中的表达模式。