Sustained Delivery of RhoA activator for Treatment of Intervertebral Disc Degeneration

关节盘源性背痛是致残的主要原因之一，涉及腰椎退行性改变。 腰间盘(IVD)。因为只有一小部分患者对常规治疗反应良好 针对症状而不是疾病的治疗，需要新的治疗方法来 治疗椎间盘退行性变(DD)。IVD的无血管性质和致密的基质使其 挑战全身给药药物到达其细胞核内的靶细胞 牙髓(NP)。而局部椎间盘内直接注射治疗性药物到NP是一种 临床相关的分娩方法，其持久性较低，并从 注射部位造成短暂的益处、偏离目标的影响和潜在的全身毒性。在……里面 根据目前的提议，我们将开发一种基于电荷的(亲和素)纳米载体系统，以提供 大分子药物(CN03)在大鼠IVD体内持续数月的给药剂量 一次给药，减少经常观察到的低渗透率或短暂的好处 IVD中的疾病修饰药物。CN03是一种RhoA GTP酶激活剂。我们最近发现 都是通过Rho GTP酶调节肌动球蛋白的收缩来实现的。我们的研究表明 RhoA可以调节主要的促炎转录因子NF-ĸB，其下游 在基质水平上包括降解效应的信号转导，使Rho GTP酶介导 肌动球蛋白收缩能力是预防促炎细胞因子诱导的新治疗靶点 IVD ECM的降解。这项MPI提案的目标是测试CN03作为一种 新的治疗药物在IVD变性的临床前模型中的应用和设计一种持续的 CN03受控地方给药系统。在目标1中，我们将量化肌动球蛋白 CN03在大鼠IVD穿刺伤模型中的收缩作用和生物学效应。在目标2中，我们将 大鼠IVD体内缓释CN03药库的合成与表征 1个月的期间。在目标3中，我们将评估CN03偶联的治疗效果 亲和素-葡聚糖在体内大鼠IVD穿刺伤模型中的作用。圆满完成这些高位 风险/高回报研究将证明肌动蛋白收缩是一种合适的疾病。 修饰DD的药物靶点，亲和素阳离子纳米结构可以提供持续的货物 大分子蛋白在IVD中最长可达1个月，并优化了CN03的传递 结合的亲和素-葡聚糖可促进体内的椎间盘功能修复。这些治疗策略 是高度翻译的，因此未来的研究将在大型动物中评估这些策略 并用于治疗症状性背痛。

Discogenic back pain, is a leading cause of disability, and involves degenerative changes of the intervertebral disc (IVD). Since only a small subset of patients responds favorably to conventional treatments which address the symptoms but not the disease, there is a need for new therapies to treat disc degeneration (DD). The avascular nature and the dense matrix of the IVD makes it challenging for systemically administered drugs to reach their target cells inside the nucleus pulposus (NP). While local intra-discal injection of therapeutic drugs directly into the NP is a clinically relevant delivery approach, it suffers from low persistence and rapid diffusion from the injection site resulting in short lived benefits, off target effects and potentially, systemic toxicity. In the current proposal, we will develop a charge based (Avidin) nanocarrier system to deliver a months long dose of a large molecular weight drug (CN03) intradiscally to the rat IVD in vivo from a single administration, reducing the often-observed low penetration or short-lived benefits of disease modifying drugs in the IVD. CN03 is a RhoA GTPase activator. We recently discovered are mediated by Rho GTPase regulation of actomyosin contractility. Our study demonstrates that RhoA can regulate the master pro-inflammatory transcription factor NF-ĸB, its downstream signaling including degradative effects at the matrix level, making Rho GTPase mediated actomyosin contractility a novel therapeutic target to prevent pro-inflammatory cytokine induced degradation of the IVD ECM. The goal of this MPI proposal is to test the efficacy of CN03 as a novel therapeutic drug in a preclinical model of IVD degeneration and to design a sustained delivery system for controlled local administration of CN03. In Aim 1, we will quantify actomyosin contractility and biological efficacy of CN03 in a rat IVD puncture injury model. In Aim 2, we will synthesize and characterize an intra-NP drug depot for sustained release of CN03 in rat IVD over a period of 1 month. In Aim 3, we will assess the therapeutic efficacy of CN03 conjugated to Avidin-Dextran in an in vivo rat IVD puncture injury model. Successful completion of these high risk/high reward studies will demonstrate that actoymyosin contractility is an appropriate disease modifying drug target for DD, that Avidin cationic nanostructures can deliver a sustained cargo of a large molecular weight protein up to 1 month in the IVD, and that optimized delivery of CN03 conjugated Avidin-Dextran improves disc functional repair in vivo. These therapeutic strategies are highly translational, and future studies will therefore evaluate these strategies in a large animal model of DD and in treating symptomatic back pain.