小鼠巨噬细胞中Nrf2介导的适应性反应及对次氯酸相关应激反应的剂量依赖性转变。
Dose-dependent transitions in Nrf2-mediated adaptive response and related stress responses to hypochlorous acid in mouse macrophages.
作者信息
Woods Courtney G, Fu Jingqi, Xue Peng, Hou Yongyong, Pluta Linda J, Yang Longlong, Zhang Qiang, Thomas Russell S, Andersen Melvin E, Pi Jingbo
机构信息
Division of Computational Biology, The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709, USA.
出版信息
Toxicol Appl Pharmacol. 2009 Jul 1;238(1):27-36. doi: 10.1016/j.taap.2009.04.007. Epub 2009 Apr 17.
Hypochlorous acid (HOCl) is potentially an important source of cellular oxidative stress. Human HOCl exposure can occur from chlorine gas inhalation or from endogenous sources of HOCl, such as respiratory burst by phagocytes. Transcription factor Nrf2 is a key regulator of cellular redox status and serves as a primary source of defense against oxidative stress. We recently demonstrated that HOCl activates Nrf2-mediated antioxidant response in cultured mouse macrophages in a biphasic manner. In an effort to determine whether Nrf2 pathways overlap with other stress pathways, gene expression profiling was performed in RAW 264.7 macrophages exposed to HOCl using whole genome mouse microarrays. Benchmark dose (BMD) analysis on gene expression data revealed that Nrf2-mediated antioxidant response and protein ubiquitination were the most sensitive biological pathways that were activated in response to low concentrations of HOCl (<0.35 mM). Genes involved in chromatin architecture maintenance and DNA-dependent transcription were also sensitive to very low doses. Moderate concentrations of HOCl (0.35 to 1.4 mM) caused maximal activation of the Nrf2 pathway and innate immune response genes, such as IL-1beta, IL-6, IL-10 and chemokines. At even higher concentrations of HOCl (2.8 to 3.5 mM) there was a loss of Nrf2-target gene expression with increased expression of numerous heat shock and histone cluster genes, AP-1-family genes, cFos and Fra1 and DNA damage-inducible Gadd45 genes. These findings confirm an Nrf2-centric mechanism of action of HOCl in mouse macrophages and provide evidence of interactions between Nrf2, inflammatory, and other stress pathways.
次氯酸(HOCl)可能是细胞氧化应激的一个重要来源。人体接触HOCl可通过吸入氯气或内源性HOCl来源,如吞噬细胞的呼吸爆发。转录因子Nrf2是细胞氧化还原状态的关键调节因子,也是抵御氧化应激的主要防御来源。我们最近证明,HOCl以双相方式激活培养的小鼠巨噬细胞中Nrf2介导的抗氧化反应。为了确定Nrf2途径是否与其他应激途径重叠,我们使用全基因组小鼠微阵列对暴露于HOCl的RAW 264.7巨噬细胞进行了基因表达谱分析。对基因表达数据的基准剂量(BMD)分析表明,Nrf2介导的抗氧化反应和蛋白质泛素化是对低浓度HOCl(<0.35 mM)作出反应时激活的最敏感生物途径。参与染色质结构维持和DNA依赖性转录的基因对极低剂量也很敏感。中等浓度的HOCl(0.35至1.4 mM)导致Nrf2途径和先天免疫反应基因(如IL-1β、IL-6、IL-10和趋化因子)的最大激活。在更高浓度的HOCl(2.8至3.5 mM)下,Nrf2靶基因表达丧失,同时许多热休克和组蛋白簇基因、AP-1家族基因、cFos和Fra1以及DNA损伤诱导的Gadd45基因的表达增加。这些发现证实了HOCl在小鼠巨噬细胞中以Nrf2为中心的作用机制,并提供了Nrf2、炎症和其他应激途径之间相互作用的证据。