title: Taraxacum officinale Weber extracts inhibit LPS-induced oxidative stress and nitric oxide production via the NF-κB modulation in RAW 264.7 cells.
abstract: BACKGROUND
  The common dandelion (Taraxacum officinale G.H. Weber ex Wiggers, Asteraceae) has been widely used in folklore medicine to treat dyspepsia, heartburn, and spleen and liver disorders.
  
  
  OBJECTIVE
  To compare the antioxidative and anti-inflammatory activities of Taraxacum officinale methanol extract (TOME) and water extract (TOWE) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and assess their constitutional differences, including luteolin, chicoric acid, and total phenol content.
  
  
  METHODS
  Antioxidative enzyme activities, nitric oxide (NO) production, and inducible NO synthase (iNOS) and nuclear factor (NF)-κB expression were estimated by biochemical analysis, the Griess reaction, reverse transcription-polymerase chain reaction, western hybridization, and electrophoretic mobility shift assay. High-performance liquid chromatography and the Folin-Ciocalteau method were used to analyze functional phytochemicals and total phenol content.
  
  
  RESULTS
  TOME and TOWE significantly reduced NO production with an IC(50) of 79.9 and 157.5 μg/mL, respectively, without cytotoxicity. Depleted glutathione (GSH) and antioxidative enzyme activities, including superoxide dismutase, catalase, GSH-peroxidase, and GSH-reductase, were restored by dandelion extracts. Both extracts inhibited LPS-stimulated iNOS gene expression and that of its transcription factor, NF-κB, in parallel with nitrite reduction. TOME showed more potent antioxidative and anti-inflammatory capacities than TOWE, which was attributable to its high total phenol, luteolin, and chicoric acid content.
  
  
  CONCLUSIONS
  These results indicate that TOME and TOWE inhibit oxidative stress and inflammatory responses through elevated de novo synthesis of antioxidative enzymes and suppression of iNOS expression by NF-κB inactivation.
authors.affiliation: Department of Smart Foods and Drugs, Inje University, Obang-dong 607, Gimhae, Gyeongnam 621-749, Republic of Korea.
authors.forename: Chung Mu
authors.initials: CM
authors.lastname: Park
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Park
authors.forename: Kyung Hee
authors.initials: KH
authors.lastname: Noh
authors.forename: Jin Hyuk
authors.initials: JH
authors.lastname: Shin
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Song
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000302:isolation & purification / Q000494:pharmacology; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology; D001483:Base Sequence; D002109:Caffeic Acids / Q000302:isolation & purification / Q000494:pharmacology; D002460:Cell Line; D020834:Ethnopharmacology; D005978:Glutathione / Q000378:metabolism; D008054:Lipid Peroxides / Q000378:metabolism; D008070:Lipopolysaccharides / Q000633:toxicity; D047311:Luteolin / Q000302:isolation & purification / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism*; D055670:Medicine, Korean Traditional; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D056910:Republic of Korea; D013386:Succinates / Q000302:isolation & purification / Q000494:pharmacology; D031205:Taraxacum / Q000737:chemistry
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D002109:Caffeic Acids; D008054:Lipid Peroxides; D008070:Lipopolysaccharides; D016328:NF-kappa B; D010936:Plant Extracts; D012333:RNA, Messenger; D013386:Succinates; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; D005978:Glutathione; D047311:Luteolin; C100435:chicoric acid