大黄素对脂多糖诱导后巨噬细胞释放炎症因子的影响

The Effect of Emodin on the Inflammatory Cytokine Production by Lipopolysaccharide-induced Macrophage

目的:研究大黄素对脂多糖(Lipopolysacchride,LPS)诱导后巨噬细胞RAW264.7释放炎症因子的影响及其分子机制。方法:将细胞分为6组,空白组,LPS组和不同浓度(1μM,5μM,10μM,25μM)大黄素+LPS组,不同浓度的大黄素预处理细胞2 h后,再加入1μg/m L LPS刺激细胞,用ELISA法检测细胞上清液中的TNF-α,IL-1β,IL-6蛋白水平,用RT-PCR法检测炎症因子mRNA表达,用Western-Blot检测核转录因子(NF-κB p65)的磷酸化。结果:LPS刺激后RAW264.7巨噬细胞炎症因子TNF-α,IL-1β,IL-6的表达和分泌明显高于空白组,而给予大黄素的LPS组表达和分泌上述细胞因子明显降低,且呈剂量依赖性。LPS刺激后的细胞NF-κB p65磷酸化明显增强,而大黄素则能抑制NF-κB p65的磷酸化,且呈剂量依赖性。结论:大黄素能明显抑制巨噬细胞释放炎症因子,降低mRNA的表达,其作用机制主要通过抑制NF-κB p65磷酸化的信号通路。

Objective： To investigate the anti- inflammatory effect of emodin on cytokine production by lipopolysaccharide- induced macrophage RAW264. 7 cell and its molecular mechanism. Methods： The macrophage cells RAW264. 7were randomly divided into six groups： blank group,LPS group,different concentrations of emodin（ 1 μM,5 μM,10 μM,25 μM） ＋ LPS groups. All groups cells were pretreated with different concentrations for 2 h,and then followed by 1 μg /m L LPS. The protein levels of TNF- α,IL- 1β,IL- 6 were detected by ELISA assay and its mRNA levels were measured by RT- PCR and NF- κB p65 phosphorylation was detected by Western- blot. Result： The expression and secretion of TNF- α,IL- 1β,IL- 6 in LPS group were increased significantly than those of blank groups,while emodin suppressed its protein and mRNA level in a dose- dependent manner. The NF- κB p65 phosphorylation was stronger than that of blank group while emodin could block the phosphorylation in a dose- dependent manner. Conclusion： Emodin can inhibit the mRNA expression and extracellar secretion of inflammatory cytokines production and its molecular mechanism is due to the inhibition of NF- κB p65 phosphorylation.