脂氧素抑制内毒素诱导大鼠原代肺成纤维细胞环氧合酶-2及前列腺素E2的表达

LipoxinA4 reduces lipopolysaccharide-induced expression of cyclooxygenase-2 and prostaglandin E2 in primary lung fibroblasts of rat

目的 探讨脂氧素对大鼠原代肺成纤维细胞环氧合酶-2及前列腺素E2表达的影响.方法 分离、纯化、鉴定得到大鼠肺成纤维细胞,用脂多糖（lipopolysaccharide,LPS）干预建立成纤维细胞体外急性炎症模型,并利用细胞增殖/毒性检测试剂MTT摸索出成纤维细胞急性炎症模型的最适LPS质量浓度和药物干预时间.分别应用不同浓度（0、100、200、400 nmol/mL）的脂氧素作用于经过LPS诱导的体外培养原代肺成纤维细胞.采用酶联免疫法（ELISA）检测细胞上清液前列腺素E2（PGE2）水平,同时应用Western blot检测原代肺成纤维细胞环氧合酶（COX-2）蛋白的表达.结果 用1 μg/mL LPS干预体外培养的原代肺成纤维细胞6h能建立较为合理的急性炎症模型.脂氧素能抑制LPS诱导的原代肺成纤维细胞环氧合酶（COX-2）蛋白的表达.对照组、LPS组、LPS组与LPS＋脂氧素组测PGE2质量浓度分别为55.84 pg/mL、411.73 pg/mL、307.07 pg/mL,LPS组与LPS＋脂氧素组间比较差异有统计学意义（P＜0.01）.结论 脂氧素能抑制LPS诱导的原代肺成纤维细胞环氧合酶-2及前列腺素E2的表达,并呈剂量依赖性.

Objective To explore the effects of lipoxinA4 on expression of cyclooxygenase-2 （COX-2） and prostaglandin E2 （PGE2） in rat primary lung fibroblast cells （LF） after lipopolysaccharide （LPS） challenge.Methods Primary lung fibroblast cells were incubated with various concentrations （0.1,1,10 μg/mL） of LPS for different lengths of time （3,6,9 h）.Then primary lung fibroblast cells were still incubated in DMEM medium containing LPS in the presence or absence of lipoxinA4.After incubation,the supematant of medium was collected and the level of PGE2 was detected by using ELISA.The cells were harvested,and COX-2 protein was analyzed by Western blot.Results The model of acute inflammation in fibroblasts was well established by administering 1 μg/mL LPS in fibroblasts for 6 hours.Induction of COX-2 protein by LPS was inhibited by lipoxinA4.The levels of PGE2 in control group,LPS group and LPS ＋ LipoxinA4 group were 55.84 pg/mL,411.73 pg/mL and 307.07 pg/mL,respectively,and there was a significantdifference between LPS group and LPS ＋ LipoxinA4 group （P 〈0.01）.Conclusion LipoxinA4 down-regulates the expression of the COX-2 induced by LPS in primary lung fibroblast cells and consequently inhibits the production of PGE2 in a dose dependent manner.