title: Methanol extracts of Stewartia koreana inhibit cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) gene expression by blocking NF-kappaB transactivation in LPS-activated RAW 264.7 cells.
abstract: Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) are involved in various pathophysiological processes such as inflammation and carcinogenesis. In a search for inhibitors of COX-2 and iNOS production we found that extracts of Stewartia koreana strongly inhibited NO and PGE2 production in LPS-treated macrophage RAW 264.7 cells. We have now shown that the mRNA and protein levels of iNOS and COX-2 are reduced by the Stewartia koreana extract (SKE). SKE inhibited expression of an NF-kappaB reporter gene in response to LPS, and gel mobility shift assays revealed that SKE reduced NF-kappaB DNA-binding activity. The extract also inhibited LPS-induced phosphorylation of IkappaB-alpha and nuclear translocation of p65. Administration of the extract reduced the symptoms of arthritis in a collagen-induced arthritic mouse model. These results indicate that Stewartia extracts contain potentially useful agents for preventing and treating inflammatory diseases.
authors.affiliation: Graduate School of Biotechnology and Institute of Life Sciences and Resources, Kyung Hee University, Yongin 446-701, Korea.
authors.forename: Tae Hoon
authors.initials: TH
authors.lastname: Lee
authors.forename: Han Bok
authors.initials: HB
authors.lastname: Kwak
authors.forename: Hong-Hee
authors.initials: HH
authors.lastname: Kim
authors.forename: Zang Hee
authors.initials: ZH
authors.lastname: Lee
authors.forename: Dae Kyun
authors.initials: DK
authors.lastname: Chung
authors.forename: Nam-In
authors.initials: NI
authors.lastname: Baek
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Kim
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000473:pathology / Q000517:prevention & control; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000235:genetics* / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D004353:Drug Evaluation, Preclinical; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D008070:Lipopolysaccharides; D008262:Macrophage Activation / Q000187:drug effects*; D000432:Methanol / Q000494:pharmacology*; D051379:Mice; D008811:Mice, Inbred DBA; D016328:NF-kappa B / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics* / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D028242:Theaceae / Q000737:chemistry*; D015533:Transcriptional Activation / Q000187:drug effects
chemical_list: D008070:Lipopolysaccharides; D016328:NF-kappa B; D010936:Plant Extracts; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2; D015232:Dinoprostone; D000432:Methanol