肾上腺素对小鼠巨噬细胞中促炎／抗炎介质比值的影响

目的：研究肾上腺素对脂多糖（LPS）诱导的小鼠单核巨噬细胞株RAW264.7中促炎介质［肿瘤坏死因子（TNF-α）、一氧化氮（NO）、环加氧酶-2（COX-2）］和抗炎介质［血红素氧化酶-1（HO-1）、白介素10（IL-10）］表达及NF-κB活化的影响。 方法： 以10 μg/L的LPS刺激体外培养的RAW264.7细胞作为炎症模型，加入不同浓度的肾上腺素（1、5、10、50 μmol/L）孵育24 h后，收集培养上清并提取细胞总蛋白，酶联免疫法测定上清中TNF-α、IL-10浓度，Griess法检测上清NO含量(以NO2-/NO3-表示)，免疫印迹法检测细胞总蛋白中COX-2、HO-1、IκB-α的含量。 结果： 10 μg/L的LPS明显诱导TNF-α、NO(NO2-/NO3-)、COX-2、IL-10及HO-1的产生；LPS+肾上腺素组与LPS单独作用组相比促炎介质TNF-α、NO(NO2-/NO3-)、COX-2的表达量显著下降，而抗炎介质IL-10、HO-1的表达却明显增强；肾上腺素与LPS共同作用组中IκB-α的含量与单独LPS作用组相比无明显差异。 结论： 肾上腺素下调LPS诱导的巨噬细胞中促炎介质的表达同时促进抗炎介质的表达，这种效应并不通过影响NF-κB的活化来实现。

Epinephrine modulates the ratio of pro-inflammatory mediators and anti-inflammatory mediators in murine macrophages treated with LPS

AIM: To investigate the effect of epinephrine on LPS-induced pro-inflammatory mediators (TNF-α, NO and COX-2) and anti-inflammatory mediators (HO-1 and IL-10) production in murine macrophage RAW264.7 cells, and to determine whether these effect is due to the influence of epinephrine on NF-κB activation. METHODS: RAW264.7 cells were cultured in vitro with 10 μg/L LPS in the absence or presence of epinephrine at variant concentrations (1, 5, 10, 50 μmol/L) for 24 hours, then the supernatants was collected for measuring TNF-α and IL-10 by ELISA and Griess reagent was used to measure NO (NO2-/NO3-) concentration. At the same time point, cells were harvested and COX-2, HO-1 and IκB-α was detected by Western blotting. RESULTS: 10 μg/L LPS significantly induced the production of TNF-α, NO (NO2-/NO3-), COX-2, HO-1 and IL-10. When epinephrine was added into the medium together with LPS, the pro-inflammatory mediators production was decreased in a dose-dependent manner, however, anti-inflammatory mediators HO-1 and IL-10 expression was enhanced by epinephrine. Epinephrine has no significant effect on IκB-α degradation in LPS-activated RAW264.7 cells. CONCLUSION: Epinephrine down-regulates LPS-induced pro-inflammatory mediator expression while promotes anti-inflammatory mediator production in murine macrophages. These effect seems to be independent of NF-κB activation.