Fu P, Birukova A A, Xing J, Sammani S, Murley J S, Garcia J G N, Grdina D J, Birukov K G
Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, 929 E. 57th Street, GCIS Bldg, Chicago, IL 60637, USA.
Eur Respir J. 2009 Mar;33(3):612-24. doi: 10.1183/09031936.00014808. Epub 2008 Nov 14.
Despite an encouraging outcome of antioxidant therapy in animal models of acute lung injury, effective antioxidant agents for clinical application remain to be developed. The present study investigated the effect of pre-treatment with amifostine, a thiol antioxidant compound, on lung endothelial barrier dysfunction induced by Gram-negative bacteria wall-lipopolysaccharide (LPS). Endothelial permeability was monitored by changes in transendothelial electrical resistance. Cytoskeletal remodelling and reactive oxygen species (ROS) production was examined by immunofluorescence. Cell signalling was assessed by Western blot. Measurements of Evans blue extravasation, cell count and protein content in bronchoalveolar lavage fluid were used as in vivo parameters of lung vascular permeability. Hydrogen peroxide, LPS and interleukin-6 caused cytoskeletal reorganisation and increased permeability in the pulmonary endothelial cells, reflecting endothelial barrier dysfunction. These disruptive effects were inhibited by pre-treatment with amifostine and linked to the amifostine-mediated abrogation of ROS production and redox-sensitive signalling cascades, including p38, extracellular signal regulated kinase 1/2, mitogen-activated protein kinases and the nuclear factor-kappaB pathway. In vivo, concurrent amifostine administration inhibited LPS-induced oxidative stress and p38 mitogen-activated protein kinase activation, which was associated with reduced vascular leak and neutrophil recruitment to the lungs. The present study demonstrates, for the first time, protective effects of amifostine against lipopolysaccharide-induced lung vascular leak in vitro and in animal models of lipopolysaccharide-induced acute lung injury.
尽管抗氧化治疗在急性肺损伤动物模型中取得了令人鼓舞的结果，但仍有待开发用于临床应用的有效抗氧化剂。本研究调查了硫醇抗氧化化合物氨磷汀预处理对革兰氏阴性菌细胞壁脂多糖（LPS）诱导的肺内皮屏障功能障碍的影响。通过跨内皮电阻的变化监测内皮通透性。通过免疫荧光检查细胞骨架重塑和活性氧（ROS）的产生。通过蛋白质印迹评估细胞信号传导。测定伊文思蓝外渗、支气管肺泡灌洗液中的细胞计数和蛋白质含量，作为肺血管通透性的体内参数。过氧化氢、LPS和白细胞介素-6导致肺内皮细胞的细胞骨架重组并增加通透性，反映了内皮屏障功能障碍。氨磷汀预处理可抑制这些破坏作用，并与氨磷汀介导的ROS产生的消除以及氧化还原敏感信号级联反应有关，包括p38、细胞外信号调节激酶1/2、丝裂原活化蛋白激酶和核因子-κB途径。在体内，同时给予氨磷汀可抑制LPS诱导的氧化应激和p38丝裂原活化蛋白激酶激活，这与减少血管渗漏和中性粒细胞向肺内募集有关。本研究首次证明了氨磷汀在体外和脂多糖诱导的急性肺损伤动物模型中对脂多糖诱导的肺血管渗漏具有保护作用。
