脂多糖及缺氧诱导肺上皮细胞释放高迁移率族蛋白B1的研究

Lipopolysaccharide and hypoxia-induced release of high mobility group box 1 in lung epithelial cells

目的研究脂多糖、缺氧对肺上皮细胞高迁移率族蛋白B1(HMGB1)释放的诱导作用及其机制。方法采用BEAS-2B人正常肺上皮细胞,分别观察100μg/L脂多糖诱导(脂多糖组)和1%O2缺氧培养(缺氧组)不同时间对细胞培养上清液中HMGB1含量的影响,同时以常规培养作为对照(对照组);并观察不同浓度N-乙酰半胱氨酸对HMGB1释放的抑制作用;HMGB1含量采用酶联免疫吸附试验检测。结果脂多糖组脂多糖诱导6h后,培养上清液中HMGB1含量为(7.4±1.6)μg/L,对照组(2.3±0.6)μg/L,脂多糖组与对照组比较差异有统计学意义(P<0.01),并随时间延长而进一步升高;缺氧组缺氧培养12h后,培养上清液中HMGB1含量为(7.1±1.6)μg/L,对照组为(2.1±0.4)μg/L,缺氧组明显高于对照组(P<0.01),同样随时间延长而进一步升高;N-乙酰半胱氨酸对缺氧培养HMGB1释放呈剂量依赖性抑制作用,但对脂多糖诱导的HMGB1释放无影响。结论脂多糖、缺氧诱导肺上皮细胞释放HMGB1,缺氧诱导机制可能与胞内氧自由基产生有关。

OBJECTIVE To study the extracellular release of high mobility group box 1（HMGB1） in lung epithelial cells induced by lipopolysaccharide and hypoxia,and their possible mechanism.METHODS The changes of HMGB1 concentration in the culture medium were investigated after BEAS-2B human lung epithelial cells were subjected to lipopolysaccharide（100 μg/L） and hypoxia（1% O2） for hours,respectively.The inhibitory effect of N-acetylcysteine was observed on HMGB1 release.The HMGB1 concentration was determined by enzyme-linked immunosorbent assay（ELISA）.RESULTS The HMGB1 concentration was（7.4±1.6）μg/L after lipopolysaccharide induced for 6 h,as compared with（2.3±0.6）μg/L in the control group,the difference was statistically significant（P〈0.01）,the HMGB1 concentration was increased with the time;the HMGB1 concentration was（7.1±1.6）μg/L after hypoxia culture for 12 h,significantly higher than（2.1±0.4）μg/L in the control group（P〈0.01）,further increasing with the time;the N-acetylcysteine dose-dependently inhibited the release of HMGB1 in hypoxia-induced BEAS-2B cells.But N-acetylcysteine showed no effect on the release of HMGB1 in lipopolysaccharide-induced cells.CONCLUSION Lipopolysaccharide and hypoxia can induce the release of HMGB1 in lung epithelial cells.The mechanism for hypoxia inducement may be involved with the intracellular reactive oxygen radicals.