title: Regulation of cyclooxygenase-2 expression by phospholipase D in human amnion-derived WISH cells.
abstract: Prostaglandins (PGs) are known to play a key role in the initiation of labor, but the mechanisms regulating their synthesis in amnion are largely unknown. In this study, the regulatory mechanisms for PGE(2) production during phospholipase D (PLD) and p38-dependent activation of WISH cells were investigated. We found that the stimulation of WISH cells with interleukin (IL)-1 beta elicited dose-dependent synthesis of cyclooxygenase-2 (COX-2) mRNA, protein, and their products, PGE(2). Moreover, the treatment of [(3)H]myristate-labeled cells in the presence of 1-butanol caused the dose-dependent formation of [(3)H]phosphatidylbutanol (PBt), a product specific to PLD activity. Pretreating the cells with 1-butanol and Ro 31-8220 inhibited the IL-1 beta-induced COX-2 expression, but 3-butanol did not affect this response. In addition, evidence that PLD was involved in the stimulation of COX-2 expression was provided by the observations that COX-2 expression was stimulated by the dioctanoyl phosphatidic acid (PA) and that the prevention of PA dephosphorylation by 1-propranolol potentiated COX-2 expression by IL-1 beta. Moreover, IL-1 beta stimulation of the cells caused the phosphorylation of p38 and extracellular signal-regulated kinase (ERK), and IL-1 beta-induced COX-2 expression was inhibited by the pretreatment of WISH cells with a p38 inhibitor, in contrast ERK upstream inhibitor had no effect. Furthermore, Ro 31-8220 inhibited IL-1 beta-induced p38 phosphorylation but not ERK phosphorylation. The results of this study indicate that in human amnion cells, IL-1 beta might activate PLD through an upstream protein kinase C to elicit p38 and finally induce COX-2 expression.
authors.affiliation: Department of Biochemistry and Molecular Biology, College of Medicine, Yeungnam University, Daegu, Korea.
authors.forename: Dae-Won
authors.initials: DW
authors.lastname: Park
authors.forename: Yoe-Sik
authors.initials: YS
authors.lastname: Bae
authors.forename: Ju-Ock
authors.initials: JO
authors.lastname: Nam
authors.forename: Jong-Ho
authors.initials: JH
authors.lastname: Kim
authors.forename: Young-Gi
authors.initials: YG
authors.lastname: Lee
authors.forename: Yoon-Ki
authors.initials: YK
authors.lastname: Park
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Ryu
authors.forename: Suk-Hwan
authors.initials: SH
authors.lastname: Baek
mesh_terms: D000650:Amnion / Q000166:cytology*; D002478:Cells, Cultured; D051546:Cyclooxygenase 2; D004789:Enzyme Activation; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D007527:Isoenzymes / Q000096:biosynthesis* / Q000235:genetics; D008565:Membrane Proteins; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010739:Phospholipase D / Q000502:physiology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis* / Q000235:genetics; D011493:Protein Kinase C / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000187:drug effects; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D007375:Interleukin-1; D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D011493:Protein Kinase C; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D010739:Phospholipase D