Functional roles of Nrf2 and NQO1 genetic variants in hyperoxic lung injury-ARDS

描述（由申请人提供）：补充氧气经常用于治疗急性呼吸窘迫综合征（ARDS）患者肺功能不全，ARDS是一种严重的急性肺损伤（ALI），影响全球数百万人。高氧性肺损伤被认为是ALI/ARDS的合适模型。本研究提出的中心假设是，nf - e2相关因子（Nrf2）和/或NADPH醌还原酶（NQO1）基因的特异性单核苷酸多态性（snp）通过降低肺和肝脏功能II期抗氧化酶的表达，导致氧介导的活性氧（ROS）的形成增加，从而增加对ALI/ARDS的易感性，从而促进ALI/ARDS的发生。同时加重了这些患者的肺损伤。为实现这些目标，我们提出以下具体目标：为了验证这一假设，即携带Nrf2或NQO1基因上特定snp的人比不携带Nrf2或NQO1基因的人更容易患ALI/ARDS，并且这些个体比携带野生型基因的人对氧化应激的敏感性更高。将分析ALI/ARDS患者或对照组的气管内吸入物是否存在snp、f2 -异前列腺素/异呋喃、大体积氧化DNA加合物水平和蛋白质氧化产物。基因表达谱也将使用来自这些个体的气管吸入物的RNA进行研究。2. 确定缺乏Nrf2和NQO1基因的小鼠更容易遭受高氧肺损伤的机制，并验证细胞色素P4501A （CYP1A）诱诱剂[例如：-萘甲酮（BNF）]或奥美拉唑（OM）通过涉及肝脏和肺部CYP1A酶的新机制来拯救缺乏功能性Nrf2或NQO1基因的小鼠免受高氧肺损伤的假设。3. 确定Nrf2或NQO1启动子上的已知snp在人肺细胞或人源化小鼠体内调节氧毒性的机制。这个目标有两个子目标。(我)。为了验证携带Nrf2或NQO1基因已知snp的人类肺细胞更容易发生氧毒性的假设。（ii）构建表达正常人Nrf2基因、NQO1基因或携带这些基因上已知snp的转基因人源化小鼠，确定snp在高氧肺损伤中的作用。组学方法，包括基因组学（微阵列）和蛋白质组学方法，将用于确定Nrf2或NQO1变异导致肺损伤的分子机制。这些目标的成功实现可能导致开发新型生物标志物的创新策略以及用于预防/治疗人类ALI/ARDS的新方法（例如，使用PPI如OM）。

DESCRIPTION (provided by applicant): Supplemental oxygen is frequently used in the treatment of pulmonary insufficiency in patients with acute respiratory distress syndrome (ARDS), which is a severe form of acute lung injury (ALI), affecting millions worldwide. Hyperoxic lung injury is recognized as an appropriate model for ALI/ARDS. The central hypothesis of the research proposed in this application is that specific single nucleotide polymorphisms (SNPs) in the genes for NF-E2-related factor (Nrf2) and/or NADPH quinone reductase (NQO1) contribute to ALI/ARDS by attenuating the expression of pulmonary and hepatic functional phase II anti-oxidant enzymes, leading to increased formation of oxygen-mediated reactive oxygen species (ROS), which in turn results in increased susceptibility to ALI/ARDS, as well as exacerbated lung damage in these patients. In order to achieve these goals, we propose the following Specific Aims: 1. To test the hypothesis that humans carrying specific SNPs on the Nrf2 or NQO1 genes will be more susceptible to develop ALI/ARDS than those who do not, and these individuals will display increased sensitivity to oxidative stress than those carrying the wild type genes. Endotracheal aspirates from individuals suffering from ALI/ARDS or controls will be analyzed for the presence of SNPs, F2-isoprostanes/isofurans, levels of bulky oxidative DNA adducts, and protein oxidation products. Gene expression profiles will also be studied using RNA from tracheal aspirates of these individuals. 2. To determine the mechanisms by which mice lacking the genes for Nrf2 and NQO1 are more susceptible to hyperoxic lung injury, and test the hypothesis that the cytochrome P4501A (CYP1A) inducer [e.g., ¿-napthoflavone (BNF)] or omeprazole (OM) will rescue the mice lacking functional Nrf2 or NQO1 genes against hyperoxic lung injury, via novel mechanisms entailing hepatic and pulmonary CYP1A enzymes. 3. To determine the mechanisms by which known SNPs on the Nrf2 or NQO1 promoter modulate oxygen toxicity in human lung cells or in humanized mice in vivo. This aim has two sub-aims. (i). To test the hypothesis that human lung cells carrying known SNPs of Nrf2 or NQO1 gene will be more susceptible to oxygen toxicity. (ii) To create transgenic humanized mice expressing the normal human Nrf2 gene or NQO1 gene or those carrying known SNPs on these genes, and determine the role of SNPs in hyperoxic lung injury. Omics' approaches, including genomics (microarrays) and proteomics approaches will be used to determine the molecular mechanisms by which Nrf2 or NQO1 variants contribute to lung injury. Successful accomplishment of the aims could lead to innovative strategies for the development of novel biomarkers as well as new approaches (e.g., use of PPI such as OM) for the prevention/treatment of ALI/ARDS in humans. PUBLIC HEALTH RELEVANCE: This project is aimed at determining the mechanisms by which these genetic variants of NF-E2-related factor (Nrf2) and/or NADPH quinone reductase (NQO1) genes contribute to acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) in humans. Successful accomplishment of the aims could lead to innovative strategies for the development of novel biomarkers as well as novel approaches for the prevention/treatment of ALI/ARDS in humans.