title: Effect of Siam weed extract and its bioactive component scutellarein tetramethyl ether on anti-inflammatory activity through NF-κB pathway.
abstract: BACKGROUND
  Siam weed (Chromolaena odorata (L.) King and Robinson) is a medicinal herb used for wound healing and inflammation-related diseases.
  
  
  OBJECTIVE
  In this study, we evaluated the molecular mechanism by which Siam weed extract (SWE) and its bioactive components, scutellarein tetramethyl ether (scu), stigmasterol, and isosakuranetin affect anti-inflammatory activity.
  
  
  METHODS
  The expression of several inflammatory proteins in RAW 264.7 (murine) macrophages was assessed by Western blot and reverse transcription-polymerase chain reaction (RT-PCR). Biochemical assays including prostaglandin E2 (PGE2) and nitric-oxide (NO) quantification were performed. Luciferase promoter activity and immunocytochemistry of Nuclear factor-κB (NF-κB) were investigated.
  
  
  RESULTS
  Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) are critical pro-inflammatory proteins. The level of protein and mRNA expression of these enzymes induced by lipopolysaccharide (LPS) was dramatically suppressed by treatment with SWE, scu, or stigmasterol compounds in a dose-dependent manner. They also reduced PGE2 and NO release. We further analyzed the NF-κB pathway and found that the scu compound suppressed IκB kinase complex alpha/beta (IKKα/β) and Inhibitory-kappa-B-alpha (IκBα), thereby suppressing COX-2 and iNOS expression.
  
  
  CONCLUSIONS
  This is the first report of the anti-inflammatory molecular mechanism in SWE and/or its bioactive component scu, indicating alteration NF-κB pathway and further providing potential uses in the treatment of inflammatory-related diseases.
authors.affiliation: Department of Biomedical and Diagnostic Sciences, The University of Tennessee, Knoxville, TN 37996, USA.
authors.forename: Hataichanok
authors.initials: H
authors.lastname: Pandith
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zhang
authors.forename: Suchitra
authors.initials: S
authors.lastname: Thongpraditchote
authors.forename: Yuvadee
authors.initials: Y
authors.lastname: Wongkrajang
authors.forename: Wandee
authors.initials: W
authors.lastname: Gritsanapan
authors.forename: Seung Joon
authors.initials: SJ
authors.lastname: Baek
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D047310:Apigenin / Q000494:pharmacology*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D036604:Chromolaena; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics; D051379:Mice; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D012333:RNA, Messenger / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics
chemical_list: D000893:Anti-Inflammatory Agents; D015850:Interleukin-6; D016328:NF-kappa B; D010936:Plant Extracts; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; C583906:scutellarein tetramethyl ether; D009569:Nitric Oxide; D047310:Apigenin; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D015232:Dinoprostone