PI_3K介导消退素D1上调脂多糖刺激的A549细胞钠离子通道

PI_3 K Mediates the Effect of Resolvin D1 on the Protein Expression of Epithelial Sodium Channel in A549 Cells Treated with Lipopolysaccharide

目的研究促炎症消退介质消退素D1(resolvin D1,RvD1)对脂多糖(lipopolysaccharide,LPS)刺激的肺泡上皮A549细胞钠离子通道α亚基(epithelial sodium channelα-subunit,α-ENaC)和γ亚基(epithelial sodium channelγ-subunit,γ-ENaC)蛋白表达的影响并探讨其机制。方法不同时间点和不同剂量的LPS刺激A549细胞建立LPS刺激A549细胞模型。将A549细胞分为:空白对照组;LPS(1μg/ml)组;LPS+RvD1(100nmol/L)组;LPS+LY294002(10μmol/L)组。用Western blot检测A549细胞中α-ENaC和γ-ENaC蛋白表达及磷酸化的磷脂酰肌醇-3-激酶(PI3K)水平。结果 LPS下调A549细胞α-ENaC和γ-ENaC蛋白表达,消退素D1抑制LPS对ENaC的下调作用,抑制LPS刺激的磷酸化PI3K。结论消退素D1通过下调磷酸化PI3K,抑制LPS对A549细胞α-ENaC和γ-ENaC蛋白表达的下调作用。

Objective To study the effect of resolvin D1 （ RvD1 ） on the protein expression of epithelial sodium channel α- subunit （α-ENaC） and epithelial sodium channel γ-subunit （γ-ENaC） in A549 cells treated with lipopolysaccharide （LPS） , and to explore the molecular mechanisms of signal pathway in RvD1 actions. Methods To establish the model of LPS - induced injury, A549 cells were treated with different concentrations of LPS and simulated by LPS at different time points. A549 cells were divided into four groups： con- trol group; LPS （LPS, lμg/ml） group; LPS ＋ RvD1 （100nmol/L） group and LPS ＋ LY294002 （10μmol/L） group. Protein expression of ENaC and phosphorylation of phosphoinositide 3 - kinase （PI3K） were detected by western blot. Results Protein expression of α - ENaC and γ- ENaC was found to be markedly decreased in the LPS group as compared with control group. This decrease was significantly reduced by RvD1 and LY294002. RvD1 inhibited phosphorylation of PI3K induced by LPS. Conclusion RvD1 increases the protein ex- pression of α- ENaC and γ- ENaC stimulated by LPS via PI3 K pathway in A549 cells.