Inhibitory effects of lignans and flavonoids in saiboku-to, a herbal medicine for bronchial asthma, on the release of leukotrienes from human polymorphonuclear leukocytes

Planta Med. 2000 Feb;66(1):88-91. doi: 10.1055/s-0029-1243120.


To identify the anti-allergic components contained in Saiboku-To, a herbal medicine for the treatment of bronchial asthma, we studied the effects of eight phenolic compounds, which have been identified as the major human metabolites of Saiboku-To, and three triterpenoids contained in Saiboku-To on the release of leukotriene (LT) from human polymorphonuclear leukocytes (PMLs) stimulated with Ca(2+)-ionophore A23,187. All phenolic compounds exhibited dose-dependent suppression on release of both LTB4 and LTC4, while triterpenoids did not show any effects, except for glycyrrhetinic acid, which selectively inhibited LTC4-release. The five phenolic compounds, magnolol, dihydroxydihydromagnolol, baicalein, medicarpine and davidigenin, were found to exert a marked inhibition on LTB4- and LTC4-release with IC50 values of 0.7-15.3 microM. The results suggest that the phenolic compounds contribute to the anti-allergic effects of Saiboku-To through suppression of LT-release from PMLs.

Publication types

  • Letter
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Asthmatic Agents / pharmacology*
  • Anti-Asthmatic Agents / therapeutic use
  • Asthma / drug therapy*
  • Drugs, Chinese Herbal / chemistry
  • Drugs, Chinese Herbal / pharmacology*
  • Drugs, Chinese Herbal / therapeutic use
  • Flavonoids / pharmacology
  • Flavonoids / therapeutic use
  • Humans
  • Leukotrienes / metabolism*
  • Lignans / pharmacology
  • Lignans / therapeutic use
  • Medicine, Kampo*
  • Neutrophils / drug effects*
  • Neutrophils / metabolism


  • Anti-Asthmatic Agents
  • Drugs, Chinese Herbal
  • Flavonoids
  • Leukotrienes
  • Lignans
  • saiboku-to