TY - JOUR T1 - Effect of Tropolone, Azulene and Azulenequinone Derivatives on Prostaglandin E<sub>2</sub> Production by Activated Macrophage-like Cells JF - Anticancer Research JO - Anticancer Res SP - 379 LP - 383 VL - 29 IS - 1 AU - MASAYUKI NISHISHIRO AU - TERUO KURIHARA AU - HIDETSUGU WAKABAYASHI AU - HIROSHI SAKAGAMI Y1 - 2009/01/01 UR - http://ar.iiarjournals.org/content/29/1/379.abstract N2 - We have previously reported that tropolone (T-3), 2,4-dibromo-7-methoxytropone (T-21), diethyl 2-chloroazulene-1,3-dicarboxylate (A-9), 1,3-difluoroazulene (A-11), 3-morpholino-1,5-azulenequinone (AQ-8) and 3,7-dibromo-1,5-azulenequinone (AQ-13) inhibited the nitric oxide (NO) production of lipopolysaccharide (LPS)-activated mouse macrophage-like RAW264.7 cells, with or without the inhibition of inducible NO synthase (iNOS) mRNA and protein expression. In order to confirm the anti-inflammatory potency, possible effects on prostaglandin (PG) E2 production and the expression of enzymes involved in the arachidonic acid pathway were investigated. Among these six compounds, only A-9 effectively inhibited the PGE2 production of the LPS-stimulated RAW264.7 cells. Western blot analysis demonstrated that A-9 inhibited phospholipase A2 (PLA2), cyclooxygenase (COX)-2 and iNOS proteins only by 12, 45 and 42%, respectively. These data demonstrate the lack of correlation between the extent of inhibition of iNOS protein expression by tropolone or azulene derivatives and that of PGE2, and suggest the possible anti-inflammatory potency of A-9. Copyright© 2009 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved ER -