A novel neuroprotective strategy

项目总结 这项应用旨在调查病毒用来阻止肝细胞凋亡的机制是否可以 被翻译和优化以阻止损伤后的神经细胞死亡。尽管有几个信号级联 负责中风和相关疾病后的神经退行性变化一直很好 治疗人类疾病的特有的、有效的神经保护疗法继续困扰着我们。因此， 旨在发现新的神经保护策略的研究，如这里描述的，是 可能具有非常高的意义。我们的实验室正在测试一种普遍的假设，即不同的细胞死亡 由不同的伤害刺激触发的或由独特的生化信号级联组成的通路， 需要一组常见的条件才能以最佳方式运行。在过去的十年里，我们定义了一种神经元 以电压依赖性K电流增强为特征的促凋亡信号级联反应。 这种现象通过为丢失细胞提供场所来确保细胞死亡计划的完成 细胞质K，为蛋白酶和核酸酶的激活建立了一个允许的环境。干扰 导致细胞凋亡性钾电流激增的过程可以有效地阻止神经细胞死亡。在……里面 哺乳动物大脑皮层和中脑神经元的电流峰是由一种依赖新生的陷阱所介导的。 Kv2.1编码的K通道胞吐插入细胞膜。值得注意的是， 丙型肝炎病毒基因组RNA非结构蛋白5A(NS5A)的翻译和加工 新近发现能有效干扰Kv2.1介导的肝细胞凋亡K电流并抑制 肝细胞死亡。在初步研究中，我们观察到NS5A也可以用来拯救 损伤后神经元及该蛋白干扰Kv2.1介导的神经细胞凋亡钾电流 涌动。在本申请中，我们打算(I)调查NS5A干扰的机制 Kv2.1功能表达，以及(Ii)定义限制通道所需的NS5A的分子结构域 功能。这些后面的实验将建立最小的NS5A派生序列，可以用于 新型神经保护探针的设计。我们研究计划的首要目标是设计出新的 损伤后保护神经元的治疗策略。我们正在探索一部小说，可能是开创性的 通过建设性地利用进化到阻止细胞死亡的生物策略来实现这一目标的方法 并将其转化为治疗中风和其他形式中风的新方法的产生 神经退行性变。

PROJECT SUMMARY This application aims to investigate whether a mechanism used by a virus to block hepatocyte apoptosis can be translated and optimized to block neuronal cell death following injury. Although several signaling cascades responsible for neurodegenerative changes following stroke and related disorders have been well characterized, effective neuroprotective therapies to treat human conditions continue to elude us. Thus, investigations designed to uncover novel neuroprotective strategies, such as those describe here, are potentially of very high significance. Our laboratory is testing the general hypothesis that distinct cell death pathways, triggered by diverse injurious stimuli or composed of unique biochemical signaling cascades, require a set of common conditions to operate optimally. Over the last ten years, we have defined a neuronal pro-apoptotic signaling cascade characterized by a robust enhancement of voltage dependent K+ currents. This phenomenon ensures the completion of cell death programs by providing a venue for the loss of cytoplasmic K+, establishing a permissive environment for protease and nuclease activation. Interfering with the processes responsible for the apoptotic K+ current surge can effectively block neuronal cell death. In mammalian cortical and midbrain neurons, the current surge is mediated by a de novo SNARE-dependent exocytotic insertion of Kv2.1-encoded K+ channels into the cell membrane. Remarkably, a product of the translation and processing of the hepatitis C virus genomic RNA, the non-structural protein 5A (NS5A), was recently shown to effectively interfere with Kv2.1-mediated apoptotic K+ currents in liver cells and inhibit hepatocyte cell death. In preliminary studies we observed that NS5A could also be employed to rescue neurons following injury and that this protein interferes with the neuronal Kv2.1-mediated apoptotic K+ current surge. In this application we intend to (i) investigate the mechanism responsible for NS5A interference with Kv2.1 functional expression, and (ii) define the molecular domains of NS5A necessary for restricting channel function. These latter experiments will establish the minimal NS5A-derived sequences that can be used for the design of novel neuroprotective probes. The overarching goal of our research program is to devise new therapeutic strategies to protect neurons following injury. We are exploring a novel, possibly groundbreaking approach to achieve this goal by constructively harnessing a biological strategy that evolved to block cell death in the liver and translating it towards the generation of novel methods to treat stroke and other forms of neurodegeneration.