S-nitrosothiol-regulated pathways in acute lung injury

描述(申请人提供)：急性肺损伤(ALI)/急性呼吸窘迫综合征(ARDS)的特征是最初的呼吸道炎症损害，导致弥漫性肺泡损伤和随后的呼吸衰竭。尽管美国每年的发病率约为20万例，死亡率接近40%，但目前尚无有效的治疗ALI/ARDS的方法。S亚硝硫醇(SNO)是一种内源性、生物活性的一氧化氮形式，其功能是抑制呼吸道上皮细胞的免疫反应途径。最近，我们在ALI的小鼠模型上证明了呼吸道SNO的急性耗竭，而吸入亚硝酸乙酯(ENO)(一种S-亚硝酸乙酯)可以防止肺损伤的发展。然而，SNO在肺内的分子靶点仍有待辨别。我们推测，通过分析气道衬里液体获得的蛋白质组特征可以用来阐明SNO调节的ALI免疫反应途径，这是ENO治疗的药理学基础。因此，我们建议：1.研究eNO对ALI大鼠气道蛋白质组的影响，明确SNO耗竭对其影响的信号转导途径；2.鉴定经S亚硝化修饰的ALI肺泡灌洗液蛋白，确定S亚硝化对其炎症活性的影响。这些特定目标的完成将有助于更全面地了解SNO在呼吸道中的调节途径，并将指导以SNO为基础的治疗方法的进一步研究，以预防和解决炎症性肺损伤。 公共卫生意义：亚硝酸乙酯(ENO)，一种S-亚硝酸气态试剂，在急性肺损伤动物模型中具有保护作用。我们将通过量化eNO治疗小鼠呼吸道中基因和蛋白质水平的变化，以及蛋白质S亚硝化来确定eNO治疗的分子靶点。

DESCRIPTION (provided by applicant): Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is characterized by an initial airway inflammatory insult that results in diffuse alveolar damage and the subsequent development of respiratory failure. Despite an incidence of ~200,000 cases/year in the United States and mortality rate approaching 40%, no effective therapy exists to treat ALI/ARDS. S-nitrosothiols (SNOs) are endogenously-produced, bioactive forms of nitric oxide that function to inhibit immune response pathways in the respiratory epithelium. Recently, we demonstrated that airway SNOs are acutely depleted in a mouse model of ALI and that treatment with inhaled ethyl nitrite (ENO), an S-nitrosylating agent, protects from the development of lung injury. However, the molecular targets of SNOs in the lung airway remain to be discerned. We hypothesize that proteomic signatures derived from analysis of airway lining fluid can be used to elucidate the SNO-regulated immune response pathways in ALI which underlie the pharmacological basis of ENO therapy. Accordingly, we propose to: 1. Characterize the effects of ENO treatment on the airway proteome in ALI and identify signaling pathways that are affected by SNO repletion; and 2. Identify BALF proteins that are modified by S- nitrosylation in ALI and determine the effects of S-nitrosylation on their inflammatory activities.. Completion of these specific aims should provide a fuller understanding of SNO-regulated pathways in the airways and will guide the further study of SNO-based therapy for the prevention and resolution of inflammatory lung injury. PUBLIC HEALTH RELEVANCE: Ethyl nitrite (ENO), a gaseous S-nitrosylating agent, is protective in animal models of acute lung injury. We will determine the molecular targets of ENO therapy by quantifying gene and protein level changes, as well as protein S-nitrosylation, in the airways of ENO-treated mice