Integrative And Molecular Studies Of Pain And Pain Contr

摘要：我们的研究计划致力于中枢神经系统伤害性信息传递的基本分子和生理过程，以及治疗顽固性疼痛的新的、有效的方法。分子研究是使用动物和体外细胞模型进行的。我们主要研究分布在背根节(DRG)的初级传入痛觉神经元，DRG支配皮肤和深层组织及其在背髓中的连接，背髓是突触信息处理的第一个部位。我们的研究发现，在持续性疼痛状态下，背根神经节和脊髓是神经元可塑性和基因表达改变的部位。通过克隆的热和化学反应离子通道在异种细胞系统中异地表达和在原代培养的背根神经节中自然表达，对物理疼痛刺激的转导的调节也在研究中。我们的目标是(1)在神经系统的这两个基本水平上了解急性和慢性疼痛的分子和细胞生物学机制，以及(2)利用这些知识来设计新的疼痛治疗方法。 临床治疗研究：我们在转化性研究和人类临床试验计划中提出了新的治疗目标，以评估严重疼痛的新止痛治疗方法。主要的方法是基于我们对通过香草素受体1(TRPV1)传递疼痛的分子机制的研究。这种分子是一种热敏的钙/钠离子通道，通过打开该通道并去极化痛觉神经末梢，将疼痛的热量转化为神经动作电位。通道的开放也受到辣椒素的刺激，辣椒素是一种香草类化学物质，也是辣椒和。我们使用一种非常有效的香草素类似物来支撑导致一类特定类型的痛觉神经元死亡的通道。我们已经与NIDA的药物治疗和药物滥用的医学后果部门建立了一个机构间工作组，将这种治疗方法带入人体临床试验。工作小组由医学、神经生物学、毒理学、化学和配方问题专家以及我们小组的麻醉师、药剂师和病理学家组成。我们还建立了获得提取活性药物的天然产品的机制，以及符合食品和药物管理局(FDA)条例的药物产品的分离、提纯和配制程序。我们目前正在与FDA敲定毒理学研究、新药研究申请，以及与NCI的IRB敲定人类临床协议。这可能是一种非常有效的方法来控制某些类型的慢性疼痛，特别是那些与癌症、关节炎和颞下颌关节紊乱、三叉神经痛和慢性神经性疼痛问题相关的疼痛。基于以上，我们提出了一项新的方案，以检验香草类激动剂诱导的神经末梢失活在治疗口面部疼痛患者的灼口综合征和疼痛成分粘膜炎中的使用。这是一种可逆的治疗方法，会产生钙超载，因此只针对神经末梢。 临床疼痛机制：某些慢性疼痛问题，如身体或口腔面部的神经病理性疼痛，没有良好的动物模型，其中之一是神经病理性疼痛问题，现在被称为慢性区域疼痛综合征(CRPS)。我们已经建立了一种临床方案来研究患者CRPS，方法是对血清进行蛋白质组学分析，并分析血清中是否存在周围神经成分的抗体。如果取得了一些成功，我们可以将分析扩展到其他几个慢性疼痛患者队列，以确定潜在的机制是否对这些类型的神经损伤诱发的神经病是通用的还是特定的。 基本疼痛机制：翻译研究的基础是我们对慢性疼痛的分子调控和周围神经末梢疼痛转导机制的研究。我们已经解决了分子可塑性的问题，部分是通过使用消减克隆、差异杂交、基因阵列和神经行为测量。这些研究代表了一种系统的尝试，试图从受伤的外周组织、背根节和背侧脊髓开始，在通路的前三个步骤理解疼痛。我们的研究揭示了基因表达在所有三个步骤中的动态调节，其方式比之前假设的更为复杂。我们研究了新分子以及神经肽、细胞因子和趋化因子的表达，并确定了具有不同组合模式的新关键分子的显著作用。除了疼痛，这些研究从根本上探索了突触可塑性的分子基础。我们假设神经元对新水平的突触或药物输入(例如学习、神经障碍、药物滥用)的反应是模块化的。“通用”改变与组织特异性基因的调节相结合，以满足新水平的刺激所产生的需求。这将导致对触发和维持慢性疼痛以及可能的其他神经系统慢性疾病的分子机制有更深入的了解。

Summary: Our research program addresses basic molecular and physiological processes of nociceptive transmission in the central nervous system and new, effective ways to treat intractable pain. The molecular research is performed using animal and in vitro cell-based models. We concentrate on primary afferent pain-sensing neurons located in dorsal root ganglion (DRG) that innervate the skin and deep tissues and their connections in the dorsal spinal cord, which is the first site of synaptic information processing for pain. Our research has identified the DRG and spinal cord as loci of neuronal plasticity and altered gene expression in persistent pain states. The regulation of transduction of physical pain stimuli is also under investigation using cloned thermal and chemo-responsive ion channels ectopically expressed in heterologous cell systems and naturally expressed in primary cultures of dorsal root ganglion. Our goals are (1) to understand the molecular and cell biological mechanisms of acute and chronic pain at these two basic levels of the nervous system and (2) to use this knowledge to devise new treatments for pain. Clinical Treatment Research:We address the new treatment goal in a translational research and human clinical trials program to evaluate new analgesic treatments for severe pain. The main approach is based on our studies of the molecular mechanisms of pain transduction through the vanilloid receptor 1 (TRPV1). This molecule is a heat-sensitive calcium/sodium ion channel and converts painful heat into nerve action potentials by opening the channel and depolarizing pain-sensing nerve terminals. Channel opening is also stimulated by capsaicin which is a vanilloid chemical and the active ingredient in hot pepper and. We use a very potent vanilloid analog to prop open the channel causing death of a specific class of pain-sensing neuron. We have established an inter-institute working group with NIDA's Division of Pharmaco-Therapeutics and Medical Consequences of Drug Abuse to bring the treatment to human clinical trial. The working group consists of experts on medical, neurobiological, toxicological, chemical and formulation issues as well as anesthesiologists, pharmacologists and pathologists from our group. We have also established mechanisms for obtaining the natural product from which the active drug is extracted and procedures for isolation purification and formulation of the drug product compliant with Food and Drug Administration (FDA) regulations. We are presently finalizing the toxicology study, the Investigational New Drug Application with the FDA and the Human Clinical Protocol with the NCI's IRB. This may be a very effective approach to control of certain types of chronic pain especially those associated with cancer, arthritis and tempro-mandibular joint disorders, trigeminal neuralgia and chronic neuropathic pain problems. Based on the above, we have submitted a new protocol to examine the use of vanilloid agonist-induced nerve terminal inactivation to treat burning mouth syndrome and pain components mucositis in human oro-facial pain patients. This is a reversible treatment that produces a calcium overload and thereby targets only the nerve endings. Clinical Pain Mechanisms: Certain chronic pain problems, such as neuropathic pain in the body or the oro-facial region, do not have good animals models, one of these is a neuropathic pain problem now referred to as Chronic Regional Pain Syndrome (CRPS). We have established a clinical protocol to study patients CRPS using proteomic analyses of serum and analysis of serum for presence of antibodies to peripheral nerve components. If there is some success we can expand the analyses to several other cohorts of chronic pain patients to establish whether the underlying mechanisms are generalize or specific to these types of nerve injury-induced neuropathies. Basic Pain Mechanisms: Underlying the translational studies are our investigations of molecular regulation in chronic pain and mechanisms of pain transduction in peripheral nerve endings. We have addressed the question of molecular plasticity, in part, by using subtraction cloning, differential hybridization, gene arrays, and neurobehavioral measurements. These studies represent a systematic attempt to understand pain at the first three steps in the pathway beginning with injured peripheral tissue, the DRG and the dorsal spinal cord. Our studies reveal the dynamic modulation of gene expression at all three steps in a more complex fashion than previously hypothesized. We have examined novel molecules as well as neuropeptide, cytokine and chemokine expression and identified prominent roles for new key molecules with distinct combinatorial patterns. In addition to pain, these studies fundamentally explore the molecular basis of synaptic plasticity. We hypothesize modularity in neuronal responses to new levels of synaptic or pharmacological input (e.g. learning, neurological disorders, drug abuse). The "generic" alterations are combined with modulation of tissue-specific genes to meet the demands generated by the new level of stimulation. This will lead to a deeper understanding of molecular mechanisms that trigger and sustain chronic pain and possibly other chronic disorders of the nervous system.