Trafficking-Dependent Signaling of Pain by Protease-Activated Receptors

蛋白酶激活受体的贩运依赖性疼痛信号传导

• 批准号: 9757759
• 负责人: NIGEL W BUNNETT
• 金额: $ 69.6万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2019-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9757759
• 关键词: Acute; Acute Pain; Adopted; Adult; Agonist; Awareness; Behavior assessment; Behavioral; Cell membrane; Cell model; Cells; Chronic; Clathrin; Cleaved cell; Colon; Crystallization; Drug Targeting; Electrophysiology (science); Endocytosis; Endosomes; Exocytosis; Family member; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; Generations; Human; Inflammation; Inflammatory Bowel Diseases; Injury; Ion Channel; Irritable Bowel Syndrome; Knowledge; Ligand Binding; Lipids; Mediating; Medical; Molecular Conformation; Mus; Nature; Neurons; Nociception; Nociceptors; Opioid; PAR-2 Receptor; Pain; Pain management; Pathologic; Pathologic Processes; Pathway interactions; Peptide Hydrolases; Persistent pain; Pharmaceutical Preparations; Physiological; Physiological Processes; Prevalence; Process; Property; Proteinase-Activated Receptors; Recycling; Signal Transduction; Signaling Protein; Site; Stimulus; Testing; Therapeutic; biophysical techniques; chronic pain; drug development; effective therapy; experimental study; extracellular; imaging approach; inhibitor/antagonist; insight; novel therapeutics; overexpression; pain relief; pain signal; prevent; receptor; receptor internalization; side effect; therapeutic target; trafficking; trans-Golgi Network

PROJECT SUMMARY Chronic pain is a major unmet medical problem. The mechanisms that underlie the transition from acute (physiological) to chronic (pathological) pain are poorly understood and current therapies are inadequate. The proposal investigates colonic pain, with relevance to irritable bowel syndrome and inflammatory bowel disease. Proteases that are activated during injury and inflammation can signal to nociceptors by cleaving protease- activated receptor-2 (PAR2), which activates transient receptor potential channels and induces long-lasting hyperexcitability and nociception. Although proteases and PAR2 have been implicated in colonic pain, the signaling mechanisms that underlie persistent protease-induced pain are far from clear, and whether PAR2 is a therapeutic target for chronic pain is uncertain. The premise is that PAR2 is uniquely suited to transmit persistent nociception due to the irreversible mechanism of proteolytic (catalytic) activation, the capacity of the receptor to signal from endosomes, and the efficient mechanisms that mobilize intracellular receptor stores. Accordingly, antagonists of endosomal PAR2 and inhibitors of mobilization provide effective pain relief. These concepts will be examined in intact mice, isolated segments of mouse and human colon, and nociceptive neurons in culture. Approaches will include: behavioral assessment of nociception, electrophysiological analysis of nociceptor activation, and biophysical and imaging approaches to assess PAR2 trafficking and signaling in nociceptors. Mice expressing fluorescent PAR2 will be used to study PAR2 trafficking. Mice with targeted deletion of PAR2 on nociceptors, and unique lipid-conjugated antagonists of endosomal PAR2, will be used to determine whether PAR2 in endosomes of nociceptors is a therapeutic target for persistent colonic pain. The studies will provide insights into the mechanisms and treatment of chronic pain. They have implications for therapeutic targeting of G protein-coupled receptors; this 1,000-member family of receptors is the target of 40% of drugs. Since many activated receptors internalize and continue to signal, effective therapy requires endosomally-targeted drugs.

项目概要 慢性疼痛是一个尚未解决的重大医学问题。从急性转变的机制 对（生理性）到慢性（病理性）疼痛的了解甚少，目前的治疗方法也不足。这 该提案调查了结肠疼痛与肠易激综合征和炎症性肠病的相关性。 在损伤和炎症过程中激活的蛋白酶可以通过裂解蛋白酶向伤害感受器发出信号 激活受体 2 (PAR2)，激活瞬时受体电位通道并诱导持久 过度兴奋和伤害感受。尽管蛋白酶和 PAR2 与结肠疼痛有关，但 引起持续性蛋白酶诱导疼痛的信号传导机制尚不清楚，PAR2 是否是一种 慢性疼痛的治疗目标尚不确定。前提是 PAR2 独特地适合传输持久性 由于不可逆的蛋白水解（催化）激活机制导致的伤害感受，受体的能力 来自内体的信号，以及动员细胞内受体储备的有效机制。因此， 内体 PAR2 拮抗剂和动员抑制剂可有效缓解疼痛。这些概念将 在完整小鼠、小鼠和人类结肠的分离片段以及培养物中的伤害性神经元中进行检查。 方法包括：伤害感受的行为评估、伤害感受器的电生理分析 激活、生物物理和成像方法来评估伤害感受器中 PAR2 的运输和信号传导。 表达荧光 PAR2 的小鼠将用于研究 PAR2 运输。靶向删除 PAR2 的小鼠 伤害感受器和内体 PAR2 的独特脂质偶联拮抗剂将用于确定是否 伤害感受器内体中的 PAR2 是持续性结肠疼痛的治疗靶点。研究将提供 深入了解慢性疼痛的机制和治疗。它们对治疗靶向具有影响 G蛋白偶联受体；这个由 1,000 个成员组成的受体家族是 40% 药物的靶标。由于许多 激活的受体内化并继续发出信号，有效的治疗需要内体靶向药物。