Imaging NFkB Activity in Relation to Animal Behavior in Peripheral Neuropathy

描述（由申请人提供）：椎间盘突出（IVD）可能与神经根压迫和生化刺激有关，从而导致炎症细胞浸润和相关的疼痛或神经根病的产生。肿瘤坏死因子-a （TNFa）是一种促炎细胞因子，被认为是IVD疝出的神经根病和神经性疼痛的早期介质。tnf诱导的炎症受转录因子NF-kB调控，数据显示NF-kB拮抗剂可以减轻周围神经损伤后的痛觉性疼痛。NRSA奖学金提出的主要工作假设是，通过无创的纵向体内成像确定的区域NF-kB活性与周围神经损伤模型中的啮齿动物功能和疼痛相关行为有直接关系。第二种假设是神经损伤区域NF-kB的局部抑制可以改变疼痛相关行为。在Aim 1中，将在含有荧光素酶NF-kB报告基因的转基因小鼠（NFkB-RE-Luc）中建立坐骨神经慢性收缩损伤（CCI）模型。神经系统中的局部NF-kB活性将通过体内发光成像进行纵向和非侵入性监测，同时测量功能（如步态）、疼痛相关行为（机械和热超敏反应、跑步轮活动）和炎症细胞浸润的特征。在CCI和假手术对照组中，功能、疼痛和炎症细胞群的测量将与区域NF-kB相关，以评估NF-kB对症状和功能障碍的贡献。在Aim 2中，姜黄素作为NF-kB抑制剂的治疗效果将通过无创体内成像以及功能和疼痛相关行为标记物在CCI后进行评估。在NFkB-RE-Luc转基因小鼠CCI后，姜黄素储存库将通过神经周围传递到坐骨神经，并通过体内发光成像纵向跟踪小鼠NF-kB活性。一组单独的动物将在CCI和特定NF-kB抑制剂SC514的神经周围递送后进行类似的研究。在两种模型中，将随时获得功能、疼痛行为和炎症细胞特征的测量，并检查与NF-kB活性的相关性，以评估局部姜黄素递送对抗NF-kB活性的能力，以及与CCI相关的症状和功能障碍。申请人将与赞助商和指导团队合作，学习最新的活体成像、步态分析和疼痛评估方面的新技术，这将促进申请人的职业发展，并促进肌肉骨骼疾病研究中成像和功能生物标志物的翻译。申请人将在研究方法、动物模型、拨款和稿件准备以及负责任的研究行为方面获得更广泛的培训，为他在生物工程方面的学术生涯做好准备。

DESCRIPTION (provided by applicant): Herniation of the intervertebral disc (IVD) may be associated with nerve root compression and biochemical irritation that contributes to inflammatory cell infiltration and associated generation of pain or radiculopathy. Tumor necrosis factor-a (TNFa) is a pro-inflammatory cytokine that is thought to be an early mediator of radiculopathy and neuropathic pain in herniated IVD. TNFa-induced inflammation is regulated by the transcription factor NF-kB, with data showing that NF-kB antagonism can reduce nociceptive pain following peripheral nerve injury. The main hypothesis of work proposed in this NRSA Fellowship is that regional NF-kB activity, determined via noninvasive, longitudinal in vivo imaging, has a direct relationship to rodent function and pain-related behaviors in a model of peripheral nerve injury. The secondary hypothesis is that localized inhibition of NF-kB in the region of nerve injury can modify pain-related behaviors. In Aim 1, a model of chronic constriction injury (CCI) of the sciatic nerve will be developed in transgenic mice (NFkB-RE-Luc) containing a luciferase NF-kB reporter. Regional NF-kB activity in the nervous system will be monitored longitudinally and non-invasively via in vivo luminescence imaging, along with time-matched measures of function (e.g., gait), pain-related behaviors (mechanical and thermal hypersensitivity, running wheel activity), and characterization of the inflammatory cell infiltrate. Measures of function, pain, and inflammatory cell populations will be correlated with regional NF-kB in the CCI and sham-operated controls in order to evaluate the contributions of NF-kB to symptoms and dysfunction. In Aim 2, the therapeutic efficacy of curcumin as an NF-kB inhibitor will be evaluated following CCI via noninvasive, in vivo imaging and markers of function and pain-related behaviors. Curcumin depots will be delivered perineural to the sciatic nerve following CCI in NFkB-RE-Luc transgenic mice, and mice will be tracked longitudinally for NF-kB activity via in vivo luminescence imaging. A separate set of animals will be similarly studied following CCI and perineural delivery of the specific NF-kB inhibitor, SC514. Measures of function, pain behaviors, and inflammatory cell characterizations will be obtained at all times and examined for correlations with NF-kB activity in both models, in order to assess an ability for local curcumin delivery to antagonize NF-kB activity, as well as symptoms and dysfunction associated with CCI. The applicant will work with the Sponsor and mentoring team to learn new techniques in state-of-the-art in vivo imaging, gait analysis, and pain assessments that will advance both the applicant's career and the translation of imaging and functional biomarkers for the study of musculoskeletal disease. The applicant will obtain broader training in research methodology, animal models, grant and manuscript preparation and responsible conduct in research that will prepare him for an academic career in bioengineering.