NOX1 and NOX2 as Therapeutic Targets in Influenza

流感病毒显示出高的突变率和重组率，很快使免疫无效， 需要每年生产疫苗。此外，高达85%的分离株对现有的抗病毒药物具有耐药性， 针对病毒本身的分子。这些因素表明，对药物的医疗需求未得到满足， 靶向宿主编码的功能，因此不受病毒选择的影响。此外，高致命性 流感病毒株（例如，1918年流感，禽流感）偶尔出现，通过 这些病毒诱导“细胞因子风暴”的倾向，其介导肺细胞功能障碍和损伤（急性 呼吸窘迫综合征或ARDS）。这些致病变化包括肺泡液的破坏 肺泡上皮细胞的转运、凋亡和中性粒细胞对肺组织的浸润/破坏， 单核细胞目前，不存在预防肺损伤的有效治疗方法。类似的变化发生在 其他病原体，包括SARS冠状病毒和炭疽，其中针对宿主的疗法被开发用于 流感也是有效的。 Nox酶是产生超氧化物和次级活性氧的NADPH氧化酶 (ROS)作为信号分子，在高浓度下直接破坏生物分子。我们提出 涉及上皮细胞Nox 1和单核细胞/PMN Nox 2产生的ROS作为关键步骤的信号级联 其：a）促进病毒复制和/或传播和B）介导肺损伤。上皮细胞活性氧的产生 Nox 1是引发细胞因子风暴和细胞功能变化的最早事件之一。使用Nox 基因敲除小鼠和抑制剂，初步证据表明，抑制Nox 1和Nox 2将 在治疗上有益于流感感染。这个应用程序代表了一个合作的努力， 埃默里大学和疾病控制中心（CDC），在那里使用高毒力流感毒株的研究 (PR8、H5 N1禽流感）可以进行。兰贝斯实验室以其在氮氧化物发现方面的专业知识而闻名， 酶学和细胞生物学，已经发现（使用高通量和低通量筛选）四个化学系列， 小分子Nox抑制剂。与埃默里药物发现研究所合作，我们的团队将 进一步开发这些抑制剂，提高其效力、异构体选择性、代谢稳定性， 药理学特性，并将作为候选药物协调临床前开发。Gangappa 实验室，疾病预防控制中心流感小组的一部分将：1）将活病毒感染到基因缺失的小鼠中， 证明Nox 1和/或Nox 2作为治疗靶点的概念验证，以及2）测试候选药物， 感染和未感染的WT小鼠。总体目标是开发新的临床前候选药物， Nox产生的ROS，从而阻断导致肺组织损伤和病毒感染的宿主信号通路。 复制/传播。此类化合物通常可用于治疗所有流感病毒株， 可能导致严重肺功能障碍/病理的其他病原体（SARS-CoV、炭疽）。

Influenza virus shows high rates of mutation and recombination that soon renders immunization ineffective and requires yearly production of vaccines. In addition, up to 85% of isolates are resistant to available antiviral molecules targeted against the virus itself. These factors demonstrate an unmet medical need for drugs that target host-encoded functions and that are therefore not subject to viral selection. Furthermore, highly lethal strains of influenza (e.g., 1918 flu, bird flu) occasionally arise, causing morbidity/mortality through the propensity of these viruses to induce a "cytokine storm" that mediates lung cell dysfunction and damage (acute respiratory distress syndrome or ARDS). Such pathogenic changes include disruptions in alveolar fluid transport, apoptosis of alveolar epithelial cells, and infiltration/destruction of lung tissue by neutrophils and monocytes. Currently, effective treatments to prevent lung damage do not exist. Similar changes occur with other pathogens including SARS-Coronovirus and anthrax, where host-directed therapies developed for influenza are also expected to be effective. Nox enzymes are NADPH-oxidases that generate superoxide and secondary reactive oxygen species (ROS) that act as signaling molecules, and in high concentrations directly damage biomolecules. We propose a signaling cascade involving both epithelial Nox1- and monocyte/PMN Nox2-generated ROS as key steps that: a) facilitate viral replication and/or spread and b) mediate lung damage. The generation of epithelial ROS by Nox1 is among the earliest events that trigger the cytokine storm and cellular functional changes. Using Nox knockout mice and inhibitors, preliminary evidence suggests that inhibition of Nox1 and Nox2 will be therapeutically beneficial in influenza infection. This application represents a collaborative effort between Emory and the Centers for Disease Control (CDC), where studies using highly virulent strains of influenza (PR8, H5N1 bird flu) can be carried out. The Lambeth Laboratory, known for its expertise in Nox discovery, enzymology and cell biology, has discovered (using high- and low-throughput screens) four chemical series of small molecule Nox inhibitors. In collaboration with the Emory Institute for Drug Discovery, our group will further develop these inhibitors, improving their potency, isoform selectivity, metabolic stability, and pharmacological properties and will coordinate preclinical development as candidate drugs. The Gangappa Laboratory, part of the Influenza group at the CDC will: 1) infect live virus into genetically deleted mice to demonstrate proof-of-concept for Nox1 and/or Nox2 as therapeutic targets, and 2) test drug candidates in infected and non-infected WT mice. The overall goal is to develop novel pre-clinical drug candidates that target Nox-generated ROS, thereby blocking host signaling pathways that lead to lung tissue damage and viral replication/spread. Such compounds will be generally useful in the treatment of all strains of influenza and likely other pathogens (SARS-CoV, anthrax) that result in severe lung dysfunction/pathology.