microRNA regulation of NMNAT-mediated Neuroprotection against Peripheral Neuropathy and Chronic Pain

项目总结 周围神经病和神经病痛可由多种遗传和环境因素引起 因素以及治疗性或娱乐性药物的使用。特别是，化疗诱导的外周 神经病(CIPN)是标准化疗方案的主要剂量限制性神经毒性副作用。完毕 68%的癌症患者在化疗后出现神经病变症状，这导致 患有慢性疼痛并不得不求助于阿片类药物使用的人口中，有相当比例的人。目前在那里 没有有效的治疗方法，这主要是由于对CIPN的体内机制缺乏了解 以及相关的周围神经病变。最近，我们优化了一种周围神经病的模型 果蝇幼虫概括了化疗的显著行为、生理和细胞方面- 诱发感觉功能障碍。我们使用这个模型的初步工作揭示了一个新的机制 并确定了一种有望缓解周围神经病的神经保护蛋白NMNAT 神经性疼痛。我们研究的最终目标是揭示 并确定神经保护机制和潜在靶点，以促进 针对CIPN和相关神经病理性疼痛的新治疗药物的开发。 我们实验室和其他实验室的广泛机制研究发现，NMNAT蛋白在果蝇和 哺乳动物是神经保护因子中最强大和最多才多艺的因素之一，与 NMNAT的表达水平与神经元的自我保护能力。令人兴奋的是，从复合屏幕上看，有几个 天然化合物被鉴定为上调NMNAT转录，我们收集了有趣的 初步结果表明，NMNAT的表达受microRNAs的调控。我们假设 天然化合物和microRNAs在转录阶段对NMNAT RNA表达的调节 MRNA剪接和mRNA稳定性允许在NMNAT介导的NAD+之间快速和动态转换 新陈代谢和神经元弹性，并赋予感觉神经元免受周围神经病的保护。 在本申请中，我们概述了以下实验：(1)鉴定调节伤害性超敏反应的microRNAs， (2)鉴定和表征天然化合物调节NMNAT的分子药理 表达，以及(3)调节NMNAT的转录调节以增强对外周的神经保护 神经病。补充应用程序的目标是将我们的测试组合扩大到包括12个 MicroRNAs和24种天然化合物。随着研究生招生工作的全面展开，我们将能够 将我们的候选人筛选组合扩大80%，并将显著提高在 确定具有高神经保护潜力的候选人。除了科学目标之外，这种多样性 补充还将支持博士培训新的天然化合物的疼痛发现和完成职业生涯 Natalie Ortiz Vega女士在天然化合物药理领域的发展目标。

PROJECT SUMMARY Peripheral neuropathy and neuropathy pain can be caused by a myriad of genetic and environment factors as well as therapeutic or recreational drug use. In particular, chemotherapy-induced peripheral neuropathy (CIPN) is the major dose-limiting neurotoxic side effect of standard chemotherapy regiments. Over 68% of cancer patients experience neuropathic symptoms after chemotherapy, and that contributes to a significant percent of the population that suffer from chronic pain and have to resort to opioid use. Currently there are no effective treatments available, largely due to a lack of understanding of the in vivo mechanisms of CIPN and related peripheral neuropathy. Recently, we have optimized a model of peripheral neuropathy using Drosophila larvae that recapitulates salient behavioral, physiological, and cellular aspects of chemotherapy- induced sensory dysfunction. Our preliminary work using this model has uncovered a new mechanism underlying peripheral neuropathy and identified a neuroprotective protein NMNAT with promising potential for mitigating neuropathic pain. The ultimate goal of our research is to uncover the endogenous mechanisms underlying peripheral neuropathy and to identify neuroprotective mechanisms and potential targets that facilitate the development of new therapeutic agents against CIPN and related neuropathic pain. Extensive mechanistic studies from our lab and others have found NMNAT proteins in Drosophila and mammals to be among the most robust and versatile neuroprotective factors, and a positive correlation between NMNAT expression levels and the neuronal self-protective capacity. Excitingly, from a compound screen, several natural compounds were identified to upregulate NMNAT transcription, and we have collected intriguing preliminary results suggesting that the expression of NMNAT is regulated by microRNAs. We hypothesize that regulation of NMNAT RNA expression by natural compounds and microRNAs at the steps of transcription, pre- mRNA splicing, and mRNA stability allows rapid and dynamic shifting between NMNAT mediated NAD+ metabolism and neuronal resilience and confers protection in sensory neurons against peripheral neuropathy. In this application we outline experiments to (1) identify microRNAs that regulate nociceptive hypersensitivity, (2) identify and characterize the molecular pharmacology of natural compounds in regulating NMNAT expression, and (3) modulate NMNAT transcriptional regulation to enhance neuroprotection against peripheral neuropathy. The objectives for the supplement application are to expand our testing portfolio to include 12 microRNAs and 24 natural compounds. With the recruitment of a full graduate student effort, we will be able to expand our candidate screening portfolio by > 80% and will significantly increase the likelihood of success in identifying candidates with high neuroprotective potential. In addition to the scientific goals, this diversity supplement will also support the PhD training in novel natural compound discovery for pain and fulfill the career development goals of Ms. Natalie Ortiz Vega in the field of natural compound pharmacology.