title: Roflumilast inhibits lipopolysaccharide-induced inflammatory mediators via suppression of nuclear factor-kappaB, p38 mitogen-activated protein kinase, and c-Jun NH2-terminal kinase activation.
abstract: Roflumilast, a potent and selective phosphodiesterase 4 (PDE4) inhibitor, has been demonstrated to be an effective anti-inflammatory agent in airway inflammatory diseases. In the present study, we investigated the mechanism of anti-inflammatory effects of roflumilast in murine macrophage cell line RAW264.7 cells. Roflumilast inhibited NO, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-1beta production via suppression of their gene expressions in lipopolysaccharide (LPS)-stimulated macrophages. To elucidate the mechanism by which roflumilast inhibits the production of inflammatory mediators, we examined the effect of roflumilast on the activation of nuclear factor-kappaB (NF-kappaB) in these cells. Roflumilast inhibited the DNA binding activity of NF-kappaB by preventing inhibitor kappaBalpha phosphorylation and degradation. The phosphorylation of mitogen-activated protein (MAP) kinases, including stress-activated protein kinase/c-Jun NH2-terminal kinase (JNK) and p38 MAP kinase, was also markedly inhibited by roflumilast. Similar to the effects of roflumilast, treatment of either SB203580 [4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)imidazole] or SP600125 [anthra(1,9-cd)pyrazol-6(2H)-one 1,9-pyrazoloanthrone], specific inhibitors of p38 MAP kinase and JNK, respectively, suppressed NO, TNF-alpha, and IL-1beta production. Consistent with in vitro results, administration of roflumilast recovered the survival rate of LPS-treated mice, with concurrent suppression of plasma levels of nitrite/nitrate, TNF-alpha, and IL-1beta. These results suggest that the inhibitory activity of roflumilast on the production of inflammatory mediators seems to be mediated via inhibition of NF-kappaB, p38 MAP kinase, and JNK activation in macrophages.
authors.affiliation: Laboratory of Molecular Pharmacology and Physiology, Medicinal Science Division, Korea Research Institute of Chemical Technology, P.O. Box 107, Yusung-Gu, Taejon 305-343, Korea.
authors.forename: Hyun Jeong
authors.initials: HJ
authors.lastname: Kwak
authors.forename: Jin Sook
authors.initials: JS
authors.lastname: Song
authors.forename: Jun Young
authors.initials: JY
authors.lastname: Heo
authors.forename: Sung Don
authors.initials: SD
authors.lastname: Yang
authors.forename: Ji-Youn
authors.initials: JY
authors.lastname: Nam
authors.forename: Hyae Gyeong
authors.initials: HG
authors.lastname: Cheon
mesh_terms: D000631:Aminopyridines / Q000633:toxicity*; D000818:Animals; D001549:Benzamides / Q000633:toxicity*; D002478:Cells, Cultured; D003521:Cyclopropanes / Q000633:toxicity; D024202:Electrophoretic Mobility Shift Assay; D004789:Enzyme Activation / Q000187:drug effects; D007375:Interleukin-1 / Q000032:analysis / Q000037:antagonists & inhibitors; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors*; D008070:Lipopolysaccharides / Q000494:pharmacology; D017737:Macrophages, Peritoneal / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D009573:Nitrites / Q000032:analysis; D010726:Phosphodiesterase Inhibitors / Q000633:toxicity*; D018675:Toxicity Tests; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000037:antagonists & inhibitors; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors*
chemical_list: D000631:Aminopyridines; D001549:Benzamides; D003521:Cyclopropanes; D007375:Interleukin-1; D008070:Lipopolysaccharides; D016328:NF-kappa B; D009573:Nitrites; D010726:Phosphodiesterase Inhibitors; D014409:Tumor Necrosis Factor-alpha; C424423:Roflumilast; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases