Tang Shimiao, Sun Siyu, Zhang Dongyang, Liu Dongyan
Medical Research Center, Liaoning Key Laboratory of Research and Application of Animal Models for Environmental and Metabolic Diseases, ShengJing Hospital, China Medical University, China.
Endoscopic Ultrasound, ShengJing Hospital, China Medical University, China.
Clin Invest Med. 2019 Dec 29;42(4):E28-E36. doi: 10.25011/cim.v42i4.33114.
Oxygen therapy is commonly used in clinical settings, but several problems may result from improper use. Oxygen poisoning involves the initiation of a series of inflammatory reactions. In this study, we compared the effects of moderate hyperoxia (40% O2) and extreme hyperoxia (85% O2) on pulmonary bronchial epithelial cells.
Normal human tracheobronchial epithelium (NHBE) cells were exposed to hyperoxia (40% and 85%) for 24 hours, and their survival rates were determined by the colorimetic assay, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide). The protein and mRNA levels of RelA, RelB, ASK1, TNF-α and secretory component (SC) were detected by immunohistochemical staining, western blot, and real-time polymerase chain reaction.
The NHBE cell survival increased in the presence of moderate hyperoxia. RelA, RelB, ASK1, TNF-α and SC expressions were significantly higher in the 85% O2 group in comparison with the control group and the 40% O2 group. In the 40% O2 group, RelA, RelB, ASK1 and TNF-α were upregulated, but SC expression was not significantly different than that of the control group. However, compared with the 85% O2 group, SC expression was significantly lower in the 40% O2 group.
These results suggest that moderate hyperoxia promotes proliferation in NHBE cells and activates TNF-α and downstream ASK1. Then TNF-α activates NF-κB and SC to play a protective role.
氧疗在临床环境中常用，但使用不当可能导致若干问题。氧中毒涉及一系列炎症反应的启动。在本研究中，我们比较了中度高氧（40%氧气）和极度高氧（85%氧气）对肺支气管上皮细胞的影响。
将正常人气管支气管上皮（NHBE）细胞暴露于高氧（40%和85%）环境中24小时，通过比色法、MTT（3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐）测定其存活率。通过免疫组织化学染色、蛋白质印迹法和实时聚合酶链反应检测RelA、RelB、ASK1、肿瘤坏死因子-α（TNF-α）和分泌成分（SC）的蛋白质和mRNA水平。
在中度高氧环境下NHBE细胞存活率增加。与对照组和40%氧气组相比，85%氧气组中RelA、RelB、ASK1、TNF-α和SC的表达显著更高。在40%氧气组中，RelA、RelB、ASK1和TNF-α上调，但SC表达与对照组无显著差异。然而，与85%氧气组相比，40%氧气组中SC表达显著更低。
这些结果表明，中度高氧促进NHBE细胞增殖并激活TNF-α及其下游的ASK1。然后TNF-α激活核因子κB（NF-κB）和SC发挥保护作用。
