外源性一氧化氮对LPS诱导的人单核巨噬细胞株NFκB活性的影响

Effects of exogenous nitric oxide on NFκB activity of U937 induced by lipopolysacchride

目的 研究NO供体硝普钠(sodiumnitroprusside ,SNP)对脂多糖(LPS)诱导的人单核巨噬细胞株U93 7核转录因子κB(NFκB)活性的影响。方法 佛波脂(PMA)诱导U93 7成熟后分为4组,分别为正常对照组(不给任何药物)、LPS组(10ng/mlLPS + 10 0ng/mlrhLBP)、低剂量SNP组(LPS +rhLBP + 5 0mol/LSNP)、高剂量SNP组(LPS +rhLBP + 5 0 0mol/LSNP)。用免疫细胞化学染色图像分析法和蛋白质定量分析法(Westernblotting)测定U93 7细胞中NFκB的活性;ELISA测定U93 7细胞培养上清液中TNF α的含量。结果 LPS刺激后NFκBP65进入核内,而LBP抑制肽组核易位明显减少。低、高剂量SNP组P65胞浆灰度比较LPS组明显减小(P <0 0 1,P <0 0 5 )。各SNP组细胞核P65的D(4 5 0 )较LPS组降低;各抑制肽组细胞浆P65的D(4 5 0 )较LPS组升高。低、高剂量SNP组TNF α较LPS组显著降低(均P <0 0 5 )。结论 SNP能显著抑制LPS诱导的U93 7细胞NFκB的活化,并降低其TNF α的释放。表明SNP对急性肺损伤或脓毒血征可能具有潜在的预防和早期治疗作用。

Objective To investigate the effects of exogenous nitric oxide(NO) on NFκB activity and TNF-α production of U937 induced by LPS. Methods U937, which was induced by PMA and became mature, was divided into 4 groups: normal control without any treatment, LPS group treated with 10 ng/ml LPS and 100 ng/ml rhLBP, low-dose exogenous NO(SNP) group treated with LPS and rhLBP and 50 mol/L SNP, and high-dose SNP group treated with LPS and rhLBP and 500 mol/L SNP. The activity of NFκB was evaluated by immunochemical staining and image analysis and Western blotting. The concentration of TNF-α in the supernatant of U937 cell culture was detected by ELISA. Results The activity of NFκB and the concentration of TNF-α in SNP treated groups were significantly lower than those in LPS and LBP treated group, but higher than those in control group. Conclusion LPS can activate NFκB through LBP and induce the release of TNF-α. SNP can reduce the release of TNF-α, which may be through inhibiting the activation of NFκB. Exogenous NO might have a potential value in the prevention and treatment of acute lung injury or sepsis.