【摘要】 目的研究黄芩苷对脂多糖诱导的小鼠巨噬细胞Toll样受体4和其下游信号分子抑制蛋白κB以及效应分子肿瘤坏死因子α表达的影响。方法分别用脂多糖(终浓度1 mg/L)或脂多糖+黄芩苷(终浓度10、50和100μmol/L)处理生长良好的小鼠巨噬细胞RAW264.7,逆转录聚合酶链反应和Western Blot检测细胞Toll样受体4表达情况和抑制蛋白κB含量变化,酶联免疫吸附法检测细胞上清液中肿瘤坏死因子α的浓度。结果脂多糖刺激RAW264.7细胞可导致Toll样受体4表达增高,促进抑制蛋白κB降解,上调肿瘤坏死因子α表达;黄芩苷预处理能降低脂多糖诱导的Toll样受体4表达增高,降低抑制蛋白κB降解,下调肿瘤坏死因子α分泌。结论黄芩苷可通过抑制Toll样受体4表达和降低抑制蛋白κB降解,影响Toll样受体4/抑制蛋白κB-核因子κB炎症信号途径,阻碍炎症因子肿瘤坏死因子α的生成,发挥抗炎作用,这可能是其抗动脉粥样硬化的作用机制之一。更多还原

【Abstract】 Aim To investigate the effects of baicalin on the expression of toll-like receptor 4(TLR4),inhibitor of κB(I-κB),and the production of tumor necrosis factor-α(TNF-α) in macrophage cells RAW264.7 induced by lipopolysaccharide(LPS).Methods RAW264.7 cells were cultured in vitro,and treated with different concentration of baicalin in the presence or absence of LPS.The mRNA and protein expression of TLR4 were determined by reverse transcription PCR and Western Blot,respectively.The expression of I-κB was detected by Western Blot.The concentrations of TNF-α in the supernatant was determined by enzyme linked immunosorbnent assay.Results LPS significantly up-regulated the expression of TLR4 and production of TNF-α in macrophage cells,and markedly inhibited the expression of I-κB.Pretreated with baicalin down-regulated LPS-induced TLR4 expression in both mRNA and protein levels,as well reduced the secretion of TNF-α.Baicalin significantly inhibited the degradation of I-κB.Conclusion Baicalin might effectively down-regulate TNF-α production in LPS-induced macrophage cells through inhibiting the expression of TLR4 and degradation of I-κB.The antiinflammation effects may be associated with the amelioration of atherosclerosis damage by baicalin.更多还原