title: Effects of flavonoids on prostaglandin E2 production and on COX-2 and mPGES-1 expressions in activated macrophages.
abstract: Prostaglandin E2 (PGE2) has a central role in inflammation and both cyclooxygenase-2 (COX-2) and prostaglandin E synthases are critical enzymes in its synthesis. In inflammation, bacterial products and cytokines enhance the expression of COX-2 and inducible microsomal prostaglandin E synthase-1 (mPGES-1) which are functionally coupled to result in increased PGE2 formation in macrophages and tissue cells. In the present study, we systematically investigated the effects of 26 naturally occurring flavonoids on PGE2 production and on COX-2 and mPGES-1 expression in activated macrophages. Twelve flavonoids, i.e., flavone, luteolin-7-glucoside, kaempferol, isorhamnetin, morin, quercetin, naringenin, taxifolin, pelargonidin, daidzein, genistein, and genistin effectively inhibited lipopolysaccharide (LPS)-induced PGE2 production. Four flavonoids (flavone, isorhamnetin, daidzein, and genistein) inhibited significantly LPS-induced COX-2 expression, while mPGES-1 expression was downregulated by kaempferol and isorhamnetin. The present study characterizes the effects of flavonoids on PGE2 production and on COX-2 and mPGES-1 expression in activated macrophages. The results add to our knowledge of the anti-inflammatory actions of flavonoids and introduce kaempferol and isorhamnetin as compounds capable of downregulating the expression of mPGES-1.
authors.affiliation: The Immunopharmacology Research Group, University of Tampere, School of Medicine and Tampere University Hospital, Tampere, Finland.
authors.forename: Mari
authors.initials: M
authors.lastname: Hämäläinen
authors.forename: Riina
authors.initials: R
authors.lastname: Nieminen
authors.forename: M Zaini
authors.initials: MZ
authors.lastname: Asmawi
authors.forename: Pia
authors.initials: P
authors.lastname: Vuorela
authors.forename: Heikki
authors.initials: H
authors.lastname: Vapaatalo
authors.forename: Eeva
authors.initials: E
authors.lastname: Moilanen
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D015232:Dinoprostone / Q000032:analysis / Q000096:biosynthesis*; D015536:Down-Regulation / Q000187:drug effects; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D019746:Intramolecular Oxidoreductases / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D051379:Mice; D000071876:Prostaglandin-E Synthases
chemical_list: D000893:Anti-Inflammatory Agents; D005419:Flavonoids; D008070:Lipopolysaccharides; D051546:Cyclooxygenase 2; D019746:Intramolecular Oxidoreductases; D000071876:Prostaglandin-E Synthases; C000605865:Ptges protein, mouse; D015232:Dinoprostone