Bouhafs R K, Rauprich P, Herting E, Schröder A, Robertson B, Jarstrand C
Department of Immunology, Microbiology, Pathology and Infectious Diseases, Division of Oral and Clinical Bacteriology, Karolinska Institutet, Huddinge Hospital, Stockholm, Sweden.
Lung. 2000;178(5):317-29. doi: 10.1007/s004080000035.
In newborn infants, group B streptococci (GBS) often cause pneumonia, with polymorphonuclear leukocytes (PMN) migrating into the lungs. Because surfactant therapy may be needed in such patients, we evaluated the interaction between GBS or GBS-stimulated PMN and a surfactant preparation (Curosurf) in vitro. The superoxide production of GBS strains or GBS-activated PMN was measured, using the nitroblue tetrazolium (NBT) test and the subsequent lipid peroxidation (LPO) as the content of malondialdehyde (MDA) and 4-hydroxyalkenals (4-HNE). The growth of GBS in surfactant was determined and related to the LPO. Finally, the effect of LPO on surfactant activity, caused by GBS-stimulated PMN, was assessed by measuring dynamic surface tension in a pulsating bubble surfactometer. Curosurf diminished the NBT reduction by both live GBS and GBS-stimulated PMN. Surfactant was peroxidized by reactive oxygen species (ROS) from both GBS and GBS-stimulated PMN in a time-dependent manner. Vitamin E significantly reduced the peroxidation level of surfactant in both cases. Surfactant peroxidation was associated with a reduction in the number of live bacteria. The biophysical activity of Curosurf was impaired by GBS-stimulated PMN, as reflected by increased minimum surface tension during cyclic compression. These findings indicate that Curosurf undergoes LPO by ROS produced by GBS and/or PMN. We speculate that exogenous surfactant preparations should be supplemented with vitamin E or another antioxidant, when given to infants with GBS pneumonia.
在新生儿中，B族链球菌（GBS）常引发肺炎，多形核白细胞（PMN）会迁移至肺部。由于此类患者可能需要进行表面活性剂治疗，我们在体外评估了GBS或GBS刺激的PMN与一种表面活性剂制剂（珂立苏）之间的相互作用。使用硝基蓝四氮唑（NBT）试验测量GBS菌株或GBS激活的PMN产生的超氧化物，并将随后的脂质过氧化（LPO）作为丙二醛（MDA）和4-羟基烯醛（4-HNE）的含量进行测定。确定GBS在表面活性剂中的生长情况并将其与LPO相关联。最后，通过在脉动气泡表面张力仪中测量动态表面张力，评估GBS刺激的PMN引起的LPO对表面活性剂活性的影响。珂立苏减少了活GBS和GBS刺激的PMN对NBT的还原作用。来自GBS和GBS刺激的PMN的活性氧（ROS）均以时间依赖性方式使表面活性剂发生过氧化。在这两种情况下，维生素E均显著降低了表面活性剂的过氧化水平。表面活性剂过氧化与活菌数量减少相关。GBS刺激的PMN损害了珂立苏的生物物理活性，这在循环压缩过程中最小表面张力增加中得以体现。这些发现表明，珂立苏会被GBS和/或PMN产生的ROS过氧化。我们推测，给患有GBS肺炎的婴儿使用外源性表面活性剂制剂时，应补充维生素E或其他抗氧化剂。
