Division of Rheumatology, Department of Internal Medicine, Soonchunhyang University, College of Medicine, Bongmyeong-Dong, Choenan, Republic of Korea.
Rheumatol Int. 2010 Feb;30(4):443-9. doi: 10.1007/s00296-009-0976-6. Epub 2009 Aug 13.
High concentration of epidermal growth factor (EGF) is found in the synovial fluid of rheumatoid arthritis (RA) that might imply the involvement of EGF in the pathogenesis of arthritic diseases. In order to investigate if EGF is involved in the regulation of cyclooxygenase-2 (COX-2) and the prostaglandin E(2) (PGE(2)) production in fibroblast like synoviocytes (FLS) from patients with RA. The levels of COX-2 and microsomal prostaglandin E synthase-1 (mPGES-1) were evaluated using RT-PCR and Western blot analysis. Electrophoretic mobility shift assay (EMSA) was performed to investigate EGF mediated DNA binding activity of nuclear factor-kappaB (NF-kappaB). PGE(2) levels were analyzed by ELISA. EGF enhanced both COX-2 protein and mRNA expressions. mPGES-1 mRNA level was also increased by EGF treatment. EGF also stimulated ERK1/2 MAPK activity and the inhibition of ERK1/2 by PD098059 (ERK1/2 specific inhibitor) resulted in the suppression of EGF-induced COX-2 expression. The DNA binding activity of NF-kappaB was remarkably increased by EGF treatment and the pretreatment of PD098059 abolished EGF-stimulated NF-kappaB activity. We also observed that the level of PGE(2) was significantly elevated with the treatment of EGF in FLS, and the pretreatment of PD098059 abolished this stimulating effect. These results suggest that EGF is involved in the inflammatory process of RA by stimulating COX-2 expression and PGE(2) production. And EGF enhanced PGE(2) production appears to be mediated via ERK1/2 MAPK and NF-kappaB pathway in FLS.
高浓度的表皮生长因子（EGF）存在于类风湿关节炎（RA）的滑液中，这表明 EGF 可能参与了关节炎疾病的发病机制。为了研究 EGF 是否参与了类风湿关节炎患者成纤维样滑膜细胞（FLS）中环氧化酶-2（COX-2）和前列腺素 E2（PGE2）的产生的调节。使用 RT-PCR 和 Western blot 分析评估 COX-2 和微粒体前列腺素 E 合酶-1（mPGES-1）的水平。通过电泳迁移率变动分析（EMSA）研究 EGF 介导的核因子-κB（NF-κB）的 DNA 结合活性。通过 ELISA 分析 PGE2 水平。EGF 增强了 COX-2 蛋白和 mRNA 的表达。EGF 处理也增加了 mPGES-1 mRNA 水平。EGF 还刺激 ERK1/2 MAPK 活性，而 PD098059（ERK1/2 特异性抑制剂）抑制 ERK1/2 导致 EGF 诱导的 COX-2 表达受到抑制。EGF 处理显着增加了 NF-κB 的 DNA 结合活性，而 PD098059 的预处理消除了 EGF 刺激的 NF-κB 活性。我们还观察到，EGF 处理可使 FLS 中 PGE2 的水平显着升高，而 PD098059 的预处理消除了这种刺激作用。这些结果表明，EGF 通过刺激 COX-2 表达和 PGE2 产生参与了 RA 的炎症过程。并且 EGF 增强 PGE2 产生的作用似乎是通过 FLS 中的 ERK1/2 MAPK 和 NF-κB 途径介导的。
