title: Suppression of tumor necrosis factor-alpha-induced neutrophil adherence responses by essential oils.
abstract: BACKGROUND
  In aromatherapy, essential oils are used as anti-inflammatory remedies, but experimental studies on their action mechanisms are very limited.
  
  
  OBJECTIVE
  To assess their anti-inflammatory activities, effects of essential oils on neutrophil activation were examined in vitro.
  
  
  METHODS
  Neutrophil activation was measured by tumor necrosis factor-alpha (TNF-alpha)-induced adherence reaction of human peripheral neutrophils.
  
  
  RESULTS
  All essential oils tested at 0.1% concentration suppressed TNF-alpha-induced neutrophil adherence,and, in particular, lemongrass, geranium and spearmint oils clearly lowered the reaction even at 0.0125%. Similar inhibitory activities for the neutrophil adherence were obtained by their major constituent terpenoids: citral, geraniol, citronellol and carvone. In contrast, very popular essential oils, tea tree oil and lavender oil, did not display the inhibitory activity at the concentration.
  
  
  CONCLUSIONS
  Thus, some essential oils used as antiinflammatory remedies suppress neutrophil activation by TNF-alpha at a low concentration (0.0125-0.025 %) in vitro.
authors.affiliation: Teikyo University Institute of Medical Mycology, 350 Otsuka, Hachioji, Tokyo 192-0395, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Abe
authors.forename: Naho
authors.initials: N
authors.lastname: Maruyama
authors.forename: Kazumi
authors.initials: K
authors.lastname: Hayama
authors.forename: Hiroko
authors.initials: H
authors.lastname: Ishibashi
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Inoue
authors.forename: Haruyuki
authors.initials: H
authors.lastname: Oshima
authors.forename: Hideyo
authors.initials: H
authors.lastname: Yamaguchi
mesh_terms: D000080462:Acyclic Monoterpenes; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D000081005:Cyclohexane Monoterpenes; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D039821:Monoterpenes / Q000494:pharmacology; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects*; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D013729:Terpenes / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D000080462:Acyclic Monoterpenes; D000081005:Cyclohexane Monoterpenes; D008070:Lipopolysaccharides; D039821:Monoterpenes; D009822:Oils, Volatile; D013729:Terpenes; D014409:Tumor Necrosis Factor-alpha; C006923:carvone; C007836:geraniol; D013755:Tetradecanoylphorbol Acetate; C007078:citronellol; C007076:citral