Pan-Lipoxygenase Inhibitors for CNS Disease

描述（由申请人提供）：对于慢性中枢神经系统疾病，如阿尔茨海默病（AD）和中风，目前没有有效的治疗方法。我们和其他人已经证明，脂氧合酶（LOXs）的激活在与这两种疾病相关的神经细胞死亡中起着核心作用，因为在细胞培养研究和模拟这些疾病的动物模型中，LOX抑制剂都减少了神经细胞死亡。此外，LOX在AD和轻度认知障碍中高度升高，而在AD转基因动物中，各种LOX和提供LOX底物的磷脂酶被基因删除大大减少了病理。然而，LOX酶被激活的分子机制及其产物如何导致神经细胞死亡尚不清楚。基于LOX代谢的中枢神经系统疗法也没有在动物模型中得到广泛的测试。为了了解信号通路并更好地了解潜在的治疗靶点，我们将在慢性氧化应激和细胞内β -淀粉样蛋白毒性的两种强大的细胞培养模型中研究lox介导的神经细胞死亡。这两种模式都与谷胱甘肽的消耗和活性氧的产生有关。此外，LOX抑制剂增强了聚集蛋白的去除，这通常与AD和衰老有关。使用这些实验系统，我们将回答以下问题。谷胱甘肽耗竭激活LOX的机制是什么？ LOX代谢物如何刺激线粒体产生ROS ？哪些特定的LOX产物参与ROS的产生和细胞死亡途径？涉及到哪些分子信号通路？抑制LOX酶活性如何增加细胞内聚集淀粉样蛋白的清除率并促进细胞存活？最后，我们将在转基因AD小鼠模型中确定最佳泛LOX抑制剂是否能够清除细胞内A¿，减少AD病理和行为缺陷，并确定主要LOX基因对AD病理的贡献。这些实验将为LOX代谢在神经细胞死亡和细胞内淀粉样蛋白代谢中的作用奠定坚实的基础，并在动物中测试这一途径，寻找新的治疗靶点。

DESCRIPTION (provided by applicant): There are currently no effective cures or treatments for chronic CNS conditions such as Alzheimer's disease (AD) and stroke. We and others have shown that the activation of lipoxygenases (LOXs) play a central role in the nerve cell death associated with both disorders because LOX inhibitors reduce nerve cell death in both cell culture studies and in animal models that mimic these disorders. Furthermore, LOXs are highly elevated in AD and mild cognitive impairment, and AD transgenic animals in which the various LOXs and the phospholipases that provide LOX substrates are genetically deleted have greatly reduced pathology. However, the molecular mechanisms by which LOX enzymes are activated and how their products cause nerve cell death are unknown. Nor have CNS therapies based upon LOX metabolism been extensively tested in animal models. To understand the signaling pathways and gain better insight into potential therapeutic targets, we will study LOX-mediated nerve cell death in two robust cell culture models of chronic oxidative stress and intracellular beta amyloid toxicity. Both paradigms are associated with the depletion of glutathione and ROS production. In addition, LOX inhibitors enhance the removal of aggregated protein, a condition associated with AD and aging in general. Using these experimental systems, we will answer the following questions. What is the mechanism by which the depletion of glutathione activates LOXs and how do the LOX metabolites stimulate ROS production from mitochondria? What are the specific LOX products involved in both ROS production and the cell death pathways? What are the molecular signaling pathways involved? How does the inhibition of LOX enzymatic activity increase the rate of clearance of aggregated intracellular amyloid and promote cell survival? Finally, we will determine if our best pan-LOX inhibitor is able to clear intracellular A¿, reduce AD pathology and behavioral deficits in a transgenic mouse AD model and define the contribution of the major LOX genes to AD pathology. These experiments will build a solid foundation for the role of LOX metabolism in nerve cell death and the metabolism of intracellular amyloid, test this pathway in animals, and identify new therapeutic targets.