Antioxidants regulators in VALI

此SCCOR应用程序的总体目标是了解与呼吸机相关肺损伤(VALI)相关的复杂事件。在项目6中，我们将确定氧化应激在VALI中的作用。氧化应激通常通过产生活性氧(ROS)与急性肺损伤有关。为了解毒ROS，肺细胞表达由经典解毒酶和第二相解毒酶组成的整合抗氧化酶(AOE)网络。然而，如果氧化应激是压倒性的，ROS可能会抑制或失活AOE系统，导致细胞损伤。我们最近展示了基因和 功能分析表明，核因子-E2相关因子2(Nrf2)在高氧性肺损伤中起关键作用。该转录因子参与肺上皮细胞的修复和拉伸，并调节II期AOES的诱导。我们还表明，NRF2基因敲除的小鼠更容易受到高氧诱导的肺损伤。与SCCOR的不同核心合作，基因组分析显示Nrf2和AP-1家族成员，如FOS相关蛋白-1(Fra-1)，以及暴露于机械通气(MV)的小鼠和狗的肺中特定的AOES上调。因此，我们假设转录因子Nrf2和Fra-1及其下游效应因子的激活在VALI的调控中起着关键作用。为了验证这一假设，我们提出了以下具体目标：1)在VALI的发展过程中，确定肺对MV和高氧的分子反应。我们将比较小鼠和小鼠肺损伤的基因和蛋白质表达谱以及损伤标志物 在VALI中，狗暴露于MV和高氧中；2)检测Nrf2的作用并确定其在VALI中的下游效应；以及3)检测FrA-1的作用并确定其在VALI中的下游效应。在这些研究中，我们将使用各自的Nrf2和Fra-1突变或野生型蛋白在肺中过表达的基因敲除和/或转基因小鼠，以及与不同核心合作的基因组学和蛋白质组学技术。这些结果在人类身上的跨物种比较和验证将分别通过与其他基础和临床研究项目的合作进行。这些研究的结果将进一步深入了解氧化应激的作用以及VALI的分子和遗传学基础。身份识别 分子靶标的研究将有助于制定新的战略，旨在最大限度地减少MV和高氧的潜在有害影响。

The overall aim of this SCCOR application is to understand the complex events related to ventilator-associated lung injury (VALI). In Project 6, we will determine the role of oxidative stress in VALI. Oxidative stress has been generally implicated in acute lung injury through production of reactive oxygen species (ROS). To detoxify ROS, lung cells express a network of integrated antioxidant enzymes (AOE) consisting of both classical and phase II detoxifying enzymes. However, if the oxidant stress is overwhelming, ROS may suppress or inactivate the AOE system resulting in cellular damage. We have recently shown by genetic and functional analysis that NF-E2 related factor 2 (Nrf2) plays a critical role in hyperoxia-induced lung injury. This transcription factor is involved in lung epithelial cell repair and stretch and regulates the induction of phase II AOEs. We have also shown that Nrf2-knockout mice are more susceptible to hyperoxia-induced lung injury. In collaboration with the various Cores of the SCCOR, genomic analysis revealed an upregulation of Nrf2 and AP-1 family members, such as fos-related protein-1 (Fra-1), as well as specific AOEs in the lungs of mice and dogs exposed to mechanical ventilation (MV). Thus, we hypothesize that activation of transcription factors such as Nrf2 and Fra-1 and their downstream effectors plays a critical role in the modulation of VALI. To test this hypothesis, we propose the following Specific Aims: 1) Determine the molecular responses of the lung in response to MV and hyperoxia in the development of VALI. We will compare gene and protein expression profiles and markers of injury in the lungs of mice and dogs exposed to MV and hyperoxia; 2) Examine the role of Nrf2 and identify its downstream effectors in VALI; and 3) Examine the role of Fra-1 and identify its downstream effectors in VALI. For these studies, we will use respective knockout and/or transgenic mice with specific lung overexpression of mutant or wildtype proteins of Nrf2 and Fra-1, as well as genomics and proteomics techniques in collaboration with the various Cores. Cross species comparison and validation of these results in human will be done through collaboration with other Basic and Clinical Research Projects, respectively. Results of these studies will provide further insight into the role of oxidative stress as well as the molecular and genetic basis of VALI. The identification of molecular targets will aid in the development of new strategies aimed at minimizing the potential I hazardous effects of MV and hyperoxia.