New models, new approaches, new horizons in corneal nerve regeneration

项目总结/摘要 角膜是身体中神经支配最多的结构，由角膜的眼分支供应。 三叉神经作为周围神经系统的一部分，角膜神经对疼痛、温度、 机械和化学刺激。它们还分泌各种营养因子和生长因子，这些因子对于 角膜的健康和功能。然而，角膜神经非常容易受到各种损伤， 包括创伤、感染、代谢失衡和治疗干预在内的机制， 屈光手术一旦受伤，它们就无法重建其基线密度或形态，从而导致 角膜功能障碍目前，还没有针对角膜神经再生的靶向治疗。的 该提案的长期目标是开发角膜神经再生的疗法。目标是 确定参与角膜神经再生的关键分子机制，以帮助了解新的实验 和治疗干预。中心假设是N-甲基-D-天冬氨酸受体（NMDAR），一种 谷氨酸受体，帮助恢复角膜神经密度和形态，从而恢复角膜功能。的 这一建议的基本原理是，NMDAR已被证明在其他神经系统中增强神经再生， 类似的周围神经系统。然而，它们在角膜神经再生中的作用仍然未知。 研究NMDAR在角膜神经再生中的作用的其他理由是基于其他研究。 已发表的研究结果：1）NMDAR在整个神经系统中表达，包括三叉神经; 2)它们已经显示出调节神经元的维持和可塑性; 3）它们调节雪旺细胞活性， 其是神经再生所必需的支持细胞;以及4）NMDAR与其他信号传导合作 已被证明可调节角膜神经再生的分子，如LDL受体相关蛋白-1 和Ephrin B型受体2。因此，我们提出了三个目标来支持我们的假设。AIM 1将确定 NMDAR在角膜感觉神经损伤修复中作用 神经和雪旺细胞独立。AIM 2将确定调节NMDAR水平对角膜内皮细胞的影响。 神经再生AIM 3将确定关键的下游效应物，包括EphB 2-Sox 2轴， 转录组学，与角膜神经再生过程中的蛋白质水平和形态学变化相关。我们 将使用创新的遗传小鼠模型，活体成像和空间基因组学来实现这些目标。的 提出的目标是重要的，因为它们将定义新的分子途径， 未来的治疗。这项工作的直接预期结果是对关键途径的严格询问， 在体角膜神经再生及其对我们对周围神经的基本认识的贡献 再生结果将产生重要的直接积极影响，因为他们将询问新的 实验方法和通知角膜神经再生的靶向治疗的发展。

PROJECT SUMMARY/ABSTRACT The cornea is the most highly innervated structure in the body, supplied by the ophthalmic branch of the trigeminal nerve. As part of the peripheral nervous system, corneal nerves respond to pain, temperature, mechanical and chemical stimuli. They also secrete various trophic and growth factors, which are essential to the health and function of the cornea. However, corneal nerves are highly susceptible to injury through various mechanisms that include trauma, infections, metabolic imbalances, and therapeutic interventions such as refractive surgeries. Once injured, they fail to reestablish their baseline density or morphology, contributing to corneal dysfunction. Currently, there are no targeted treatments specific for corneal nerve regeneration. The long-term goal of this proposal is to develop therapies for corneal nerve regeneration. The objective is to determine key molecular mechanisms involved in corneal nerve regeneration to help inform new experimental and therapeutic interventions. The central hypothesis is the N-Methyl-D-aspartate receptors (NMDAR), a type of glutamate receptor, help restore corneal nerve density and morphology, and therefore, corneal function. The rationale underlying this proposal is that NMDARs have been shown to enhance nerve regeneration in other analogous peripheral nervous systems. However, their role in corneal nerve regeneration remains unknown. Additional justification for investigating the role of NMDARs in corneal nerve regeneration is based on other published findings: 1) NMDARs are expressed throughout the nervous system, including the trigeminal nerves; 2) they have been shown to regulate neuronal maintenance and plasticity; 3) they regulate Schwann cell activity, which are supporting cells essential to nerve regeneration; and 4) NMDARs cooperate with other signaling molecules that have been shown to regulate corneal nerve regeneration such as LDL-receptor-related protein-1 and Ephrin type-B receptor 2. Therefore, we propose three aims to support our hypothesis. AIM 1 will determine the role of NMDAR in corneal nerve maintenance and regeneration by conditionally deleting NMDAR in sensory nerves and Schwann cells independently. AIM 2 will determine the effect of modulating NMDAR levels on corneal nerve regeneration. AIM 3 will determine key downstream effectors, including the EphB2-Sox2 axis, with spatial transcriptomics, correlated with protein levels and morphologic changes during corneal nerve regeneration. We will pursue these aims using innovative genetic mouse models, intravital imaging, and spatial genomics. The proposed aims are significant because they will define new molecular pathways that will inform the development of future therapies. The immediate expected outcome of this work is rigorous interrogation of key pathways in corneal nerve regeneration in vivo and contribution to our fundamental understanding of peripheral nerve regeneration. The results will have an important direct positive impact because they will interrogate new experimental approaches and inform the development of targeted therapies for corneal nerve regeneration.