牙龈卟啉单胞菌脂多糖对人单核细胞株THP-1前列腺素E2合成通路的影响  

Effect of lipopolysaccharide of Porphyromonas gingivalis on prostaglandin E2 biosynthetic pathway in human monocytic cell strain THP-1

作　　者：吴燕岷[1] 陈莉丽[1] 孙伟莲[1] 严杰[2] 

机构地区：[1]浙江大学医学院附属第二医院口腔科,杭州310009 [2]浙江大学医学院病原生物学教研室

出　　处：《中华口腔医学杂志》2008年第8期483-487,共5页Chinese Journal of Stomatology

基　　金：国家自然科学基金（30471888）

摘　　要：目的探讨牙龈卟啉单胞菌脂多糖（lipopolysaccharide of Porphyromonas gingivalis，Pg-LPS）在诱导细胞前列腺素E2（prostaglandin E2，PGE2）合成通路上是否具有不同于大肠杆菌脂多糖（lipopolysaccharide of Escherichia coli，Ec-LPS）的特点。方法用Pg-LPS和Ec-LPS分别作用于人单核细胞株THP-1，用酶免疫法检测PGE2的浓度。用液闪计数法观察花生四烯酸释放水平的变化。用反转录聚合酶链反应和Western blotting法分别检测胞质磷脂酶A：（cytosolic phospholipaseA2，cPLA2）、环氧化酶2（cyclooxygenase-2，COX-2）和微粒体前列腺素E合成酶1（microsomal prostaglandin Esynthase-1，mPGES-1）的mRNA和蛋白表达水平。结果Pg-LPS诱导PGE2合成和释放花生四烯酸的水平明显弱于Ec-LPS（P〈0．05）。PGE2水平增高在Pg-LPS作用6h出现，24h达峰值，为（221．40±29．46）ng／L；或Ec-LPS作用1～48h，为（161．80±17．31）～（379．80±37．35）ng／L。COX-2和mPGES-1的最高表达出现在Pg-LPS作用16h，或Ec-LPS作用8h和16h时。cPLA2的抑制剂AACOCF3可降低LPS诱导的花生四烯酸释放水平的增高，但对PGE2的合成无明显作用。COX-2阻断剂NS-398可显著减少PGE2产生。结论Pg-LPS对PGE2合成通路的作用弱于Ec-LPS。Pg-LPS作用下PGE2的合成主要是COX-2和mPGES-1表达增高所致，与cPLA2关系不大。Objective To investigate the effect of lipopolysaccharide of Porphyromonas gingivalis （Pg-LPS） on the bio-thythetic pathway of prostaglandin E2 （PGE2 ） and its difference from lipopolysaccharide of Escherichia coli（ Ec-LPS ）. Methods Purified Pg-LPS and Ec-LPS were used to stimulate a human monocytic cell strain THP-1. PGE2 concentration was determined by an enzyme immunoassay kit. The release of tritium labeled arachidonic acid （AA） was detected by a liquid scintillation counter. Reverse transcription polymerase chain reaction and western blot were used to analyse the expression of cytosolic phospholipase A2 （cPLA2） enzyme, cyclooxygenase-2 （ COX-2 ）, and microsomal prostaglandin E synthase-1 （ mPGES-1 ）. Results The effect of Pg-LPS on induction of PGE2 and release of AA was significantly weaker than that of Ec-LPS （P 〈0. 05）. Increased secretion of PGE2 was observed after stimulation with Pg-LPS for 6 h, which peak at 24 h at （221.40 ± 29. 46） ng/L; or with Ec-LPS for 1-48 h ,at （ 161.80±17.31 ） - （379. 80 ±37.35 ） ng/L. The highest levels of COX-2 and mPGES-1 were shown after 16 h treatment by Pg-LPS, or after 8 h and 16 h by Ec-LPS respectively, cPLA2 inhibitor AACOCF3 could lower the level of LPS-induced release of AA, while it did not influence the production of PGE2. COX-2 inhibitor NS-398 could remarkably reduce the concentration of PGE2. Conclusions Pg-LPS showed delayed and weaker effect on PGE2 biosynthetic pathway than Ec-LPS. Pg-LPS-induced PGEz synthesis was mainly due to enhanced expression of COX-2 and mPGES-1, whereas cPLA2 played an insignificant role.

关 键 词：紫单胞菌 龈 脂多糖类 地诺前列酮 前列腺素E合成酶 

分 类 号：R686[医药卫生—骨科学]