Post-Traumatic Inflammatory Signaling in CRPS

CRPS 中的创伤后炎症信号传导

• 批准号: 8856553
• 负责人: DAVID J. CLARK
• 金额: --
• 依托单位: VETERANS ADMIN PALO ALTO HEALTH CARE SYS
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8856553
• 关键词: Adverse effects; Affect; Afferent Neurons; Age; Analgesics; Animals; Anti-Inflammatory Agents; Anti-inflammatory; Antibodies; Antigens; Attenuated; Biological Assay; Blast Injuries; Blood Cell Count; Blood Vessels; Bulla; Calcitonin Gene-Related Peptide; Cell Count; Cells; Characteristics; Chronic; Clinical; Clinical Management; Clinical Trials; Complex Regional Pain Syndromes; Confocal Microscopy; Consensus; Contracture; Contralateral; Cutaneous; Cytokine Activation; Data; Development; Disease; Distal; Edema; Effectiveness; Endothelial Cells; Enzyme Inhibitor Drugs; Enzyme Inhibitors; Etanercept; Etiology; Extravasation; FDA approved; Foundations; Fracture; Functional disorder; Future; Generations; Goals; Growth Factor; Head; Healthcare Systems; Hindlimb; Hypersensitivity; Immobilization; Immunohistochemistry; In Situ Hybridization; In Vitro; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Response; Injury; Interleukin-1 beta; Interleukin-6; Intravenous; Joints; Lead; Light; Limb structure; Lymphocyte; Maps; Mediating; Mediator of activation protein; Methods; Modeling; Nerve; Nerve Growth Factors; Neuraxis; Neurogenic Inflammation; Neuropeptides; Neutrophil Infiltration; Nociception; Opiates; Osteoporosis; Pain; Pathologic; Patients; Pattern; Pentoxifylline; Perfusion; Peripheral; Pharmaceutical Preparations; Phase; Population; Process; Production; Proteins; Quality of life; Rattus; Redness; Risk; Risk Factors; Role; Safety; Sampling; Sedimentation process; Sensory; Side; Signal Pathway; Signal Transduction; Skin; Skin Temperature; Source; Staging; Stimulus; Substance P; Substance P Receptor; Symptoms; Syndrome; T-Lymphocyte; Testing; Therapeutic Effect; Time; Touch sensation; Translating; Trauma; Treatment Efficacy; Tryptase; Tumor Necrosis Factor-alpha; Up-Regulation; Vasodilation; Veterans; War; Western Blotting; Work; abstracting; allodynia; anakinra; base; bisphosphonate; body system; bone; bone loss; chronic pain; control trial; cytokine; disability; drug efficacy; effective therapy; improved; inhibitor/antagonist; injured; keratinocyte; limb fracture; mRNA Expression; macrophage; mast cell; new therapeutic target; novel; prevent; protein expression; receptor; receptor expression; research study; response; sex; sound; tibia; translational study; tumor necrosis factor-alpha inhibitor; vascular inflammation

DESCRIPTION (provided by applicant): 6. Project Summary/Abstract: Limb trauma can lead to the development of a complex regional pain syndrome (CRPS). At onset this syndrome presents a baffling array vascular, bone, and nociceptive changes in the injured limb that can evolve into chronic edema, pain, weakness, contractures, and osteoporosis. Currently there is no consensus on either the pathophysiology or treatment for CRPS and there is a need for translational studies to identify therapeutic targets and novel pharmacologic approaches. The most common etiology for CRPS is distal limb fracture and we have developed a rat fracture model resembling CRPS. After distal tibia fracture and cast immobilization for 4 weeks the rats develop chronic unilateral hindlimb warmth, edema, increased spontaneous protein extravasation, periarticular osteoporosis, hindlimb unweighting, and allodynia, changes paralleling those observed in CRPS patients. The vascular and nociceptive changes characteristic of the early stages of CRPS suggest an inflammatory process, yet there is little evidence for an immunocyte response. On the other hand, there is compelling evidence that neurogenic inflammatory responses mediated by substance P (SP) signaling are exaggerated in the CRPS limb and in the rat fracture model. Substance P signaling stimulates keratinocyte proliferation, activation, and cytokine and growth factor production in vitro, including tumor necrosis factor alpha (TNF), interleukin-1 beta (IL-1), interleukin-6 (IL-6), and nerve growth factor (NGF). TNF and IL-6 are up-regulated in experimental skin blisters in CRPS limbs and we have observed that all these inflammatory cytokines and NGF are up-regulated in the hindpaw skin of the fracture rats. When we administered an SP receptor antagonist to the fracture rats the increase in cutaneous cytokines and NGF was prevented. Fracture rats treated with cytokine inhibitors or anti-NGF failed to develop allodynia and had attenuated hindlimb unweighting, indicating an important role for cytokine and growth factor signaling in the development of trauma induced pain. Based on these data we propose that fracture and immobilization enhance SP endothelial signaling in the injured limb, resulting in vascular inflammation with increased extravasation, edema and warmth. We also postulate that facilitated SP signaling activates keratinocyte expression of pronociceptive cytokines and NGF, resulting in post-traumatic pain symptoms. The primary objective of this proposal is to identify target-specific treatments for CRPS using approved or soon to be approved medications. This work is directed at understanding the peripheral sources of mediators supporting post-traumatic inflammation and pain sensitization and determining whether these mediators are associated with risk factors for the development of post-traumatic CRPS. We will also determine whether peripheral inflammatory mediators contribute to the transition of post-traumatic pain into a chronic pain state. The specific aims are; 1) to use immunohistochemistry methods to map post-traumatic changes in SP, inflammatory cytokine, and NGF signaling in keratinocytes, endothelial cells, and mast cells in the skin of CRPS patients and in a rat fracture model of CRPS, 2) identify risk factors for development of CRPS-like sequelae in the rat fracture model, including age, sex, ACE inhibitor usage, and immobility, and then use PCR, EIA, western blotting and extravasation assays to determine whether facilitated SP signaling and increased inflammatory cytokine and NGF expression are associated with an increased risk of developing post-traumatic CRPS in these conditions, and 3) establish the efficacy of the global cytokine inhibitor pentoxifylline, the SP receptor antagonist LY303870, and the NGF antibody tanezumab in preventing or attenuating the transition from early post-traumatic pain to chronic pain, and to evaluate their efficacy for treating chronic pain (16 weeks post-fracture) in the CRPS fracture model. These studies are expected to generate translational data supporting future clinical CRPS trials, with the potential for improving the efficacy and safety of the clinical management of post-traumatic pain syndromes.

描述（由申请人提供）： 6. 项目摘要/摘要：肢体创伤可导致复杂区域疼痛综合征 (CRPS)。这种综合征在发病时会在受伤肢体上出现一系列令人困惑的血管、骨骼和伤害性变化，并可能演变成慢性水肿、疼痛、虚弱、挛缩和骨质疏松。目前，对于 CRPS 的病理生理学或治疗方法尚未达成共识，需要进行转化研究来确定治疗靶点和新的药理学方法。 CRPS 最常见的病因是远端肢体骨折，我们开发了一种类似于 CRPS 的大鼠骨折模型。远端胫骨骨折和石膏固定 4 周后，大鼠出现慢性单侧后肢发热、水肿、自发性蛋白质外渗增加、关节周围骨质疏松、后肢失重和异常性疼痛，这些变化与 CRPS 患者中观察到的变化相似。 CRPS 早期阶段的血管和伤害性变化特征表明存在炎症过程，但几乎没有证据表明存在免疫细胞反应。另一方面，有令人信服的证据表明，由 P 物质 (SP) 信号传导介导的神经源性炎症反应在 CRPS 肢体和大鼠骨折模型中被夸大。 P 物质信号传导在体外刺激角质形成细胞增殖、活化以及细胞因子和生长因子的产生，包括肿瘤坏死因子 α (TNF)、白细胞介素 1 β (IL-1)、白细胞介素 6 (IL-6) 和神经生长因子（NGF）。 TNF 和 IL-6 在 CRPS 四肢实验性皮肤水泡中上调，我们观察到所有这些炎症细胞因子和 NGF 在骨折大鼠后爪皮肤中上调。当我们给骨折大鼠施用 SP 受体拮抗剂时，皮肤细胞因子和 NGF 的增加被阻止。用细胞因子抑制剂或抗 NGF 治疗的骨折大鼠未能出现异常性疼痛，并且后肢失重减轻，表明细胞因子和生长因子信号传导在创伤引起的疼痛的发展中发挥重要作用。基于这些数据，我们提出骨折和固定会增强受伤肢体中的 SP 内皮信号传导，导致血管炎症，并增加外渗、水肿和发热。我们还假设促进的 SP 信号传导激活角质形成细胞表达伤害性细胞因子和 NGF，从而导致创伤后疼痛症状。 该提案的主要目标是使用已批准或即将批准的药物确定 CRPS 的针对性治疗方法。这项工作旨在了解支持创伤后炎症和疼痛敏化的介质的外周来源，并确定这些介质是否与创伤后 CRPS 发生的危险因素相关。我们还将确定外周炎症介质是否有助于创伤后疼痛向慢性疼痛状态的转变。具体目标是； 1) 使用免疫组织化学方法绘制 CRPS 患者皮肤和 CRPS 大鼠骨折模型中角质形成细胞、内皮细胞和肥大细胞中 SP、炎症细胞因子和 NGF 信号的创伤后变化，2) 确定危险因素用于大鼠骨折模型中 CRPS 样后遗症的发生，包括年龄、性别、ACE 抑制剂的使用和不动，然后使用 PCR、EIA、蛋白质印迹和外渗测定来确定促进的 SP 信号传导以及炎症细胞因子和 NGF 表达的增加是否与这些情况下发生创伤后 CRPS 的风险增加有关，以及 3) 确定全局细胞因子抑制剂己酮可可碱、SP 受体拮抗剂 LY303870 和 NGF 抗体的功效tanezumab 预防或减轻早期创伤后疼痛向慢性疼痛的转变，并评估其治疗 CRPS 骨折慢性疼痛（骨折后 16 周）的功效 模型。这些研究预计将产生支持未来临床 CRPS 试验的转化数据，并有可能提高创伤后疼痛综合征临床管理的有效性和安全性。