Develop a combinatorial therapy for spinal cord injury

项目摘要 切断的中枢神经系统轴突不能再生，很大程度上是因为成人固有的生长能力降低 神经元和恶劣的轴突延伸环境。Co-I的实验室发现Wnt家族分子和它们的 脊髓损伤(SCI)后受体上调并介导再生 其中 成人 损伤的纤维束的破坏。 几种Wnt受体中，Ryk在调节发育过程中排斥性轴突生长中起关键作用。 中枢神经系统损伤后。胶质瘢痕产生的硫酸软骨素蛋白多糖(CSPGs)受到强烈抑制 轴突延伸，是治疗中枢神经系统损伤的主要外在分子靶点。PI的团队设计了 靶向CSPG受体LAR和PtPσ关键活性区域阻断其功能的小肽 并证明了它们对促进轴突生长的高效性。用3号受体分别阻断这两种受体 组合肽促进受损的中枢神经系统轴突的强劲再生。我们假设对两者的抑制 WNT和CSPG信号代表了增强神经元生长能力和减少 病变部位的环境抑制影响。我们建议刺激成人强健的轴突再生。 基因和药物抑制脊髓损伤后Ryk和LAR/PtPσ的作用 我们实验室提供的方法。在目标1中，我们将研究转基因缺失Ryk plus的协同作用 σ受体在促进脊髓损伤小鼠轴突再生和恢复中的作用我们会 确定删除Ryk+LAR或Ryk+Ptpσ受体是否协同刺激轴突 脊髓损伤后双基因敲除小鼠的生长和增强神经元可塑性。在目标2中，我们将确定是否 用抗体或选择性拮抗剂药理阻断RyK、LAR和PtPσ受体 促进成年大鼠脊髓损伤后轴突的再生和恢复。我们将比较两个方案的有效性 以单个受体为靶点的治疗方法，促进多个降支血管的再生和恢复 脊髓损伤后运动功能恢复。在目标3中，我们将研究阻断两种或三种联合疗法 受体在脊髓横断或挫伤大鼠中产生更好的轴突再生和功能恢复，旨在 确定患有脊髓损伤的哺乳动物的最佳治疗方法。基于我们初步研究的可喜结果，我们 预测我们的联合策略将促进损伤轴索的戏剧性再生和 活体内的运动功能。我们在受伤后给予可交付化合物的新策略可能 促进开发一种治疗中枢神经系统病变的实用组合疗法。

Project Summary Severed CNS axons fail to regenerate largely because of the reduced intrinsic growth capacity of adult neurons and poor environment for axon extension. The Co-I's Lab finds that the Wnt family molecules and their receptors are upregulated after spinal cord injury (SCI) and mediates regrowth Among adult failure of injured fiber tracts. several Wnt receptors, Ryk is crucial for mediating repulsive axon growth during development and in CNS after injury.Chondroitin sulfate proteoglycans (CSPGs) generated by glial scars strongly suppress axon extension and are major extrinsic molecular targets for treating CNS injury. The PI's group designed small peptides to block functions of CSPG receptors LAR and PTPσ by targeting their critical activity domains and demonstrated their high efficiency for promoting axon growth. Blocking each of the two receptors with 3 combined peptides promotes robust regeneration of injured CNS axons. We hypothesize that inhibiting both Wnt and CSPG signals represents a dual approach of enhancing neuronal growth capacity and reducing environmental inhibitory influence at the lesion site. We propose to stimulate robust axon regrowth in adult rodents with transection or contusion SCI by inhibiting Ryk and LAR/PTPσ with genetic and pharmacological approaches available in our labs. In Aim 1, we will study synergistic actions of transgenically deleting Ryk plus each of LAR/PTPσ receptors on promoting axon regeneration and recovery in mice with SCI. We will determine whether deleting Ryk plus LAR or Ryk plus PTPσ receptors acts synergistically to stimulate axon growth and enhance neuronal plasticity in double knockout mice after SCI. In Aim 2, we will determine whether blocking each of Ryk, LAR and PTPσ receptors with antibody or selective antagonists pharmacologically promotes axon regeneration and recovery in adult rats with SCI. We will compare effectiveness of the treatments that target individual receptors in promoting regrowth of multiple descending tracts and recovery of locomotor functions after SCI. In Aim 3, we will study whether combination therapies that block two or three receptors yield better axon regrowth and functional recovery in rats with transection or contusion SCI, aiming to identify the optimal therapy for mammals with SCI. Based on the promising results from our pilot studies, we predict that our combined strategies will promote dramatic regeneration of injured axon tracts and recovery of locomotion function in vivo. Our novel strategy of administering deliverable compounds post-injury may facilitate development of a practical combinatorial therapy for CNS lesions.