谷氨酰胺对内毒素诱导大鼠肺泡Ⅱ型上皮细胞TNF-α表达和NF-κB活化的影响

The effects of glutamine pretreatment on tumor necrosis factor-α release and nuclear factor-κB activation in lipopolysaccharide-induced alveolar epithelial cells from rats

目的:探讨Gln对内毒素(LPS)诱导的大鼠肺泡Ⅱ型上皮细胞肿瘤坏死因子(TNF)-α表达和NF-κB活性的影响。方法:原代培养大鼠肺泡Ⅱ型上皮细胞,分为0、0.5、2.0、10.0 mmol/L Gln及10 mmol/L Gln、空白对照共六个组,作用8 h后,前四组1μg/mL LPS刺激24 h。用ELISA法测定细胞上清TNF-α的水平,电泳迁移率改变试验(EMSA)检测细胞内NF-κB活性。结果:Gln预处理可降低LPS诱导大鼠肺泡Ⅱ型上皮细胞TNF-α的表达,并且其作用呈剂量依赖性,在10 mmol/L浓度最为显著;Gln预处理对NF-κB活性有明显地抑制作用。结论:Gln预处理可抑制NF-κB活性,并降低LPS诱导的大鼠肺泡Ⅱ型上皮细胞TNF-α的表达,从而起到免疫调节的作用。

Objective ： To investigate the effects of glutamine （Gln） on tumor necrosis factor （TNF） -α release and nuclear factor （NF）-KB activation in lipopolysaccharide-induced type Ⅱ alveolar epithelial （ AT- Ⅱ） cells from rats. Methods ： Primary cultured AT- Ⅱ cells were pre-treated with 0, 0.5, 2.0, 10.0 mmol/L Gln for 8 hours. Then the cells were stimulated with or without 1 ug/mL LPS for 24 hours. The supernatants were obtained for TNF-α measurement. The activation of NF-kB in the cells were assessed with electrophoretic mobility shift assay （EMSA）. Results： Supplementation of Gin attenuated the release of TNF-α in LPS-stimulated AT-Ⅱ cells in a dose-dependant manner. There were significant differences when the concentration of Gln above 0.5 mmoL/L as compared to zero. Gin could inhibite the activation of NF-kB induced by LPS. Conclusion ： Glutamine pretrcatment could attenuate the release of TNF-α and inhibite the activation of NF-kB in LPS-stimulated AT- Ⅱ cells.