Astrocyte Calcium Signaling in Neuropathic Pain

项目摘要 慢性疼痛是许多疾病的标志，包括神经和脊髓损伤。电流 疼痛管理的支柱包括镇痛药和麻醉药，尽管它们具有 不确定的疗效和已知的副作用。更安全和更有效的疼痛管理方法是 迫切需要，但基础研究的知识差距阻碍了发展和翻译， 新的治疗方法。为了加速这一过程，需要更好地了解细胞和分子基础， 需要疼痛信号。脊髓是一个重要的信号枢纽，参与沟通疼痛相关的 外周器官和大脑之间的信号。作为中枢神经系统内感觉整合的第一个部位， 在中枢神经系统（CNS）中，它在中枢敏化中起重要作用。很多注意力都集中在 神经元细胞类型和电路有助于这一过程。然而，人们对它的了解却少得多。 非神经元细胞的贡献，如星形胶质细胞。而脊髓星形胶质细胞的形态学变化 与慢性疼痛的发作和进展的关系已经得到了很好的表征，但对它们的作用知之甚少。 动态活动模式以及它们如何与神经元尖峰或性别特异性免疫反应相关。 从历史上看，技术挑战已经阻止了在临床前动物模型中的这种测量， 自然条件。双光子和小型化单光子成像的最新进展 这些方法使得能够实时测量行为哺乳动物中的细胞钙活性。这 第一次深入了解了来自皮肤中机械感受器和伤害感受器的感觉信息是如何敏锐地 激活背角神经元和星形胶质细胞。结合使用这些尖端的成像方法 通过计算、遗传和行为技术，本提案的目标是定义星形胶质细胞如何 钙活性的变化与神经病理性疼痛的发生和进展有关，其靶向操作如何 影响神经元和非神经元反应，以及它如何改变分子信号和动物行为。 这项研究的基本原理是，通过揭示细胞和分子机制， 有助于疼痛发作或进展，可以设计新的镇痛干预措施。三个具体目标将 1）确定星形胶质细胞钙兴奋如何与自然条件下的神经病理性疼痛相关 2）确定星形胶质细胞钙兴奋的抑制如何调节正常和异常的感觉 3）确定星形胶质细胞钙兴奋介导的分子途径 正常和异常感觉处理的调节。总之，这项工作将揭示如何变化， 星形胶质细胞活性在分子、细胞和行为水平上促进神经病理性疼痛。日本将延长 目前的模型，如何非神经元细胞有助于持续性疼痛的具体和中枢神经系统的功能广泛。

PROJECT SUMMARY Chronic pain is a hallmark of many disease conditions, including nerve and spinal cord injury. Current mainstays of pain management include analgesics and anesthetics, treatments that are used despite their uncertain efficacy and known side effects. Safer and more productive approaches for pain management are urgently needed, but knowledge gaps in basic research have hampered the development and translation of novel treatments. To accelerate this process an improved understanding of the cellular and molecular basis of pain signaling is required. The spinal cord is a crucial signaling hub involved in communicating pain-related signals between peripheral organs and the brain. As the first site of sensory integration within the central nervous system (CNS), it plays essential roles in central sensitization. Much attention has focused on the neuronal cell types and circuits that contribute to this process. However, considerably less is known about the contributions of non-neuronal cells, such as astrocytes. While morphological changes in spinal astrocytes in relation to onset and progression of chronic pain have been well characterized, little is known about their dynamic activity patterns and how they relate to neuronal spiking or sex-specific immune responses. Historically, technical challenges have prevented such measurements in preclinical animal models under naturalistic conditions. The recent development of two-photon and miniaturized one-photon imaging approaches has enabled real-time measurement of cellular calcium activity in behaving mammals. This has provided first insights into how sensory information from mechanoreceptors and nociceptors in the skin acutely activates dorsal horn neurons and astrocytes. Using these cutting-edge imaging approaches in combination with computational, genetic, and behavioral techniques, the objective of this proposal is to define how astrocyte calcium activity changes in relation to neuropathic pain onset and progression, how its targeted manipulation influences neuronal and non-neuronal responses, and how it alters molecular signaling and animal behavior. The rationale for the proposed research is that by uncovering cellular and molecular mechanisms that contribute to pain onset or progression, new analgesic interventions can be devised. Three specific aims will be pursued: 1) Determine how astrocyte calcium excitation relates to neuropathic pain under naturalistic conditions; 2) Determine how inhibition of astrocyte calcium excitation modulates normal and aberrant sensory processing, and 3) Determine molecular pathways involved in astrocyte calcium excitation-mediated modulation of normal and aberrant sensory processing. In summary, this work will uncover how changes in astrocyte activity contribute to neuropathic pain on molecular, cellular, and behavioral levels. It will extend current models of how non-neuronal cells contribute to persistent pain specifically and CNS function broadly.