Pyocyanin-induced toxicity in A549 respiratory cells is causally linked to oxidative stress
Pyocyanin-induced toxicity in A549 respiratory cells is causally linked to oxidative stress
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DOI：
10.1016/j.tiv.2011.05.004
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发表时间：
2011-10-01
影响因子：
3.2
通讯作者：
Anoopkumar-Dukie, Shailendra
中科院分区：
文献类型：
--
作者：
Gloyne, Lee S.;Grant, Gary D.;Anoopkumar-Dukie, Shailendra
绿脓菌素是铜绿假单胞菌产生的一种毒力因子，对哺乳动物细胞具有多种损伤作用。一些证据表明，这种损害主要是由其产生ROS和耗尽宿主抗氧化防御机制的能力介导的。然而，氧化应激的因果作用尚未得到最终证明。ROS的产生，抗氧化剂水平和细胞毒性的平行测量提供了令人信服的证据表明，绿脓菌素诱导的细胞毒性A549呼吸道细胞是由急性ROS的产生和随后的氧化应激介导的。用H2 O2荧光探针Amplex Red和DCFH-DA测定绿脓菌素增加A549细胞内ROS水平，抗氧化剂N-乙酰半胱氨酸可减弱绿脓菌素的这种作用。此外，绿脓菌素诱导的细胞内GSH水平的耗竭暴露后24小时，也防止预处理的细胞与NAG。在这些条件下，NAG保护细胞免受绿脓菌素诱导的细胞毒性，如通过刃天青还原为试卤灵和活细胞计数测量的，强烈支持氧化应激的因果作用。最后，我们还表明，绿脓菌素诱导的免疫和炎症转录因子NF-κ B B在A549细胞中的激活可能是由增加的ROS介导的。对绿脓菌素诱导的细胞毒性机制的理解增加，最终可能导致更好的策略，以降低与慢性铜绿假单胞菌感染相关的毒力。(C)2011爱思唯尔有限公司保留所有权利。
Pyocyanin, a virulence factor produced by Pseudomonas aeruginosa, has many damaging effects on mammalian cells. Several lines of evidence suggest that this damage is primarily mediated by its ability to generate ROS and deplete host antioxidant defence mechanisms. However, a causal role for oxidative stress has not yet been demonstrated conclusively. Parallel measures of ROS production, antioxidant levels and cytotoxicity provide convincing evidence that pyocyanin-induced cytotoxicity in A549 respiratory cells is mediated by acute ROS production and subsequent oxidative stress. Pyocyanin increased ROS levels in A549 cells as measured by the fluorescent H2O2 probes Amplex Red and DCFH-DA. These effects were attenuated by the antioxidant N-acetylcysteine. Furthermore, pyocyanin-induced depletion of intracellular GSH levels 24 h after exposure was also prevented by pre-treatment of cells with NAG. Under these conditions, NAG protected cells against pyocyanin-induced cytotoxicity as measured by resazurin reduction to resorufin and viable cell counts, strongly supporting a causal role for oxidative stress. Finally, we also show that pyocyanin-induced activation of the immune and inflammatory transcription factor NF-kappa B in A549 cells is likely mediated by increased ROS. This increased understanding of mechanisms underlying pyocyanin-induced cytotoxicity may ultimately lead to better strategies for reducing the virulence associated with chronic P. aeruginosa infection. (C) 2011 Elsevier Ltd. All rights reserved.