title: Illicium verum extract inhibits TNF-α- and IFN-γ-induced expression of chemokines and cytokines in human keratinocytes.
abstract: BACKGROUND
  Illicium verum Hook. f. (star anise) has been used in traditional medicine for treatment of skin inflammation, rheumatism, asthma, and bronchitis. This study investigated the anti-inflammatory effects of Illicium verum extract (IVE) in the human keratinocyte HaCaT cell line.
  
  
  METHODS
  We investigated the effectiveness of IVE in tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ)-induced human keratinocytes. To measure the effects of IVE on chemokine and pro-inflammatory cytokine expression in HaCaT cells, we used the following methods: cell viability assay, reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, western blotting, and luciferase reporter assay.
  
  
  RESULTS
  IVE inhibited the expression of TNF-α/IFN-γ-induced mRNA and protein expression of thymus and activation-regulated chemokine (TARC/CCL17), macrophage-derived chemokine (MDC/CCL22), interleukin (IL)-6, and IL-1β. Furthermore, IVE decreased TNF-α/IFN-γ-induced mRNA expression of intercellular adhesion molecule-1 (ICAM-1). IVE inhibited nuclear factor (NF)-κB translocation into the nucleus, as well as phosphorylation and degradation of IκBα. IVE inhibited TNF-α/IFN-γ-induced NF-κB and signal transducer and activator of transcription (STAT)1 activation in a dose-dependent manner. In addition, IVE significantly inhibited activation of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), and Akt. Furthermore, IVE contained 2.14% trans-anethole and possessed significant anti-inflammatory activities.
  
  
  CONCLUSIONS
  IVE exerts anti-inflammatory effects by suppressing the expression of TNF-α/IFN-γ-induced chemokines, pro-inflammatory cytokines, and adhesion molecules via blockade of NF-κB, STAT1, MAPK, and Akt activation, suggesting that IVE may be a useful therapeutic candidate for inflammatory skin diseases, such as atopic dermatitis.
authors.affiliation: Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Yoon-Young
authors.initials: YY
authors.lastname: Sung
authors.forename: Young Sang
authors.initials: YS
authors.lastname: Kim
authors.forename: Ho Kyoung
authors.initials: HK
authors.lastname: Kim
mesh_terms: D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002460:Cell Line; D016207:Cytokines / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D005638:Fruit; D006801:Humans; D029523:Illicium; D018799:Intercellular Adhesion Molecule-1 / Q000235:genetics; D007371:Interferon-gamma; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha
chemical_list: D000893:Anti-Inflammatory Agents; D016207:Cytokines; D010936:Plant Extracts; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D007371:Interferon-gamma