Persistent COMT-dependent Pain: Role of beta-adrenergic Receptors

持续性 COMT 依赖性疼痛：β-肾上腺素能受体的作用

• 批准号: 8725747
• 负责人: Andrea G Nackley
• 金额: $ 35.39万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8725747
• 关键词: Acute; Adrenergic Agents; Adrenergic Antagonists; Adrenergic Receptor; Animal Model; Animals; Astrocytes; Attenuated; Automobile Driving; Behavioral; Brain region; Carrageenan; Catechol O-Methyltransferase; Catecholamines; Cells; Cerebrospinal Fluid; Characteristics; Complex; Data; Depressed mood; Development; Dose; Enzymes; Epinephrine; Exhibits; Fibromyalgia; Gene Expression; Genetic; Healthcare; Interleukin-1; Interleukin-12; Interleukin-6; Knockout Mice; Location; Maps; Measures; Mechanics; Mediating; Methodology; Methods; Microglia; Modeling; Molecular; Mus; Neuroglia; Neurons; Nitric Oxide; Nociception; Onset of illness; Outcome Study; Pain; Pathway interactions; Patients; Perception; Peripheral; Persistent pain; Physiology; Play; Production; Rattus; Risk; Role; Signaling Molecule; Site; Spinal; Spinal Cord; Stimulus; System; TNF gene; Techniques; Temporomandibular Joint Disorders; Testing; Tumor Necrosis Factor-alpha; Withdrawal; Work; adrenergic; beta-adrenergic receptor; brain tissue; clinically relevant; cytokine; effective therapy; genetic variant; inhibitor/antagonist; insight; novel; novel strategies; pain behavior; peripheral blood; protein expression; research study; transmission process

DESCRIPTION (provided by applicant): Complex persistent pain conditions, such as fibromyalgia (FM) and temporomandibular disorder (TMD), are ineffectively treated because the underlying molecular mechanisms remain largely unknown. Work by our group and others suggests that these conditions are due, in large part, to diminished activity of catechol-O- methyltransferase (COMT; an enzyme that metabolizes catecholamines), which results in elevated levels of catecholamines and increased activity of beta2/3-adrenergic receptors (beta2/3ARs). However, the exact mechanisms whereby beta2/3ARs mediate COMT-dependent pain are unclear and necessitate further study. Preliminary data show that activation of beta2/3ARs may increase pain sensitivity by increasing the expression of downstream signaling molecules. We show that COMT inhibition results in increased expression of the proinflammatory cytokines tumor necrosis factor-alpha (TNF1), interleukin-12 (IL-12), and interleukin-6 (IL-6) as well as nitric oxide (NO), and that this increase is blocked by 2AR antagonists. [[Additional data further suggest that COMT- dependent pain is mediated in part by peripheral adrenergic systems as adrenalectomized rats lacking peripheral epinephrine exhibit reduced COMT-dependent pain sensitivity. The present application proposes to extend this work by applying diverse methodologies in a novel animal model of persistent pain produced by sustained COMT inhibition in order to elucidate the role that betaARs play in driving persistent pain at cellular and systems levels. First, we will apply behavioral pharmacologic methods in intact rats, adrenalectomized rats, and COMT knockout mice to determine the site of action whereby beta-adrenergic systems drive persistent COMT-dependent pain. Second, we will apply immunocytochemical techniques to determine the role of betaARs in mediating the activation of neurons, microglia, and astrocytes following sustained COMT inhibition. Third, we will apply molecular biologic methods to determine the role of betaARs in mediating the expression of proinflammatory cytokines and NO following sustained COMT inhibition. We hypothesize that persistent COMT-dependent pain produces long-term changes in cellular activity and expression of proinflammatory cytokines and NO by way of peripheral, spinal, and central beta2/3ARs. The novel approach of these studies will 1) identify the subtype and location of betaARs that contribute to persistent pain conditions such as FM and TMD, 2) characterize the long-term consequences of sustained betaAR activation on neurons and glia located in spinal and brain regions that relay pain information, 3) characterize the long-term consequences of sustained 2AR activation on proinflammatory cytokines and NO, which represent validated markers of nociception, and 4) determine the ability of beta2/3AR antagonists to suppress the transmission of nociceptive information. The outcome of these studies will provide new insights into mechanisms underlying maladaptive pain conditions as well as contribute to the identification of previously unexploited targets (e.g., beta2- and beta3ARs) for development of effective therapies for patients with persistent pain conditions.]]

描述（由申请人提供）：复杂的持续性疼痛病症，例如纤维肌痛（FM）和颞下颌关节紊乱（TMD），由于其潜在的分子机制仍然很大程度上未知，因此治疗效果不佳。我们小组和其他人的工作表明，这些情况在很大程度上是由于儿茶酚-O-甲基转移酶（COMT；一种代谢儿茶酚胺的酶）活性降低，从而导致儿茶酚胺水平升高和 beta2/3 活性增加-肾上腺素能受体（β2/3AR）。然而，β2/3AR 介导 COMT 依赖性疼痛的确切机制尚不清楚，需要进一步研究。初步数据表明，β2/3AR 的激活可能通过增加下游信号分子的表达来增加疼痛敏感性。我们发现 COMT 抑制导致促炎细胞因子肿瘤坏死因子-α (TNF1)、白细胞介素 12 (IL-12) 和白细胞介素 6 (IL-6) 以及一氧化氮 (NO) 的表达增加，并且这种增加被 2AR 拮抗剂阻断。 [[其他数据进一步表明，COMT 依赖性疼痛部分是由外周肾上腺素能系统介导的，因为缺乏外周肾上腺素的肾上腺切除大鼠表现出 COMT 依赖性疼痛敏感性降低。本申请提出通过在持续 COMT 抑制产生的持续性疼痛的新型动物模型中应用不同的方法来扩展这项工作，以阐明 betaAR 在细胞和系统水平驱动持续性疼痛中所发挥的作用。首先，我们将在完整大鼠、肾上腺切除大鼠和 COMT 敲除小鼠中应用行为药理学方法，以确定 β-肾上腺素能系统驱动持续性 COMT 依赖性疼痛的作用位点。其次，我们将应用免疫细胞化学技术来确定 betaAR 在持续 COMT 抑制后介导神经元、小胶质细胞和星形胶质细胞激活中的作用。第三，我们将应用分子生物学方法来确定持续 COMT 抑制后 betaAR 在介导促炎细胞因子和 NO 表达中的作用。我们假设持续性 COMT 依赖性疼痛通过外周、脊髓和中枢 β2/3AR 导致细胞活性和促炎细胞因子和 NO 表达的长期变化。这些研究的新方法将 1) 确定导致 FM 和 TMD 等持续性疼痛的 betaAR 的亚型和位置，2) 表征持续 betaAR 激活对脊髓和大脑区域的神经元和神经胶质细胞的长期后果传递疼痛信息，3) 表征持续 2AR 激活对促炎细胞因子和 NO 的长期后果，代表伤害感受的有效标记，4) 确定 β2/3AR 拮抗剂抑制传递的能力伤害性信息。这些研究的结果将为适应不良疼痛的机制提供新的见解，并有助于识别以前未开发的靶点（例如 beta2- 和 beta3AR），以开发针对持续性疼痛的患者的有效疗法。]]