Effects of luteolin, quercetin and baicalein on immunoglobulin E-mediated mediator release from human cultured mast cells

Clin Exp Allergy. 2000 Apr;30(4):501-8. doi: 10.1046/j.1365-2222.2000.00768.x.


Background: Flavonoids have a variety of activities including anti-allergic activities, and are known to inhibit histamine release from human basophils and murine mast cells.

Objective: The effects of luteolin, a flavone, on the immunoglobulin (Ig) E-mediated allergic mediator release from human cultured mast cells (HCMCs) were investigated and compared with those of baicalein and quercetin.

Methods: HCMCs were sensitized with IgE, and then treated with flavonoids before challenge with antihuman IgE. The amount of released mediators was determined as was mobilization of intracellular Ca2+ concentration, protein kinase C (PKC) translocation and phosphorylation of intracellular proteins were detected after anti-IgE stimulation.

Results: Luteolin, baicalein and quercetin inhibited the release of histamine, leukotrienes (LTs), prostaglandin D2 (PGD2), and granulocyte macrophage-colony stimulating factor (GM-CSF) from HCMC in a concentration-dependent manner. Additionally, the three flavonoids inhibited A23187-induced histamine release. As concerns Ca2+ signalling, luteolin and quercetin inhibited Ca2+ influx strongly, although baicalein did slightly. With regard to PKC signalling, luteolin and quercetin inhibited PKC translocation and PKC activity strongly, although baicalein did slightly. The suppression of Ca2+ and PKC signallings might contribute to the inhibition of mediator release. The activation of extracellular signal-regulated kinases (ERKs) and c-Jun NH2-terminal kinase (JNK), that were activated just before the release of LTs and PGD2 and GM-CSF mRNA expression in IgE-mediated signal transduction events, were clearly suppressed by luteolin and quercetin. In contrast, the flavonoids did not affect the activation of p38 mitogen-activated protein kinase (p38 MAPK) pathway.

Conclusion: These results indicate that luteolin is a potent inhibitor of human mast cell activation through the inhibition of Ca2+ influx and PKC activation.

MeSH terms

  • Calcium / physiology
  • Cells, Cultured
  • Drug Interactions
  • Flavanones*
  • Flavonoids / immunology
  • Flavonoids / pharmacology*
  • Histamine Release / drug effects*
  • Humans
  • Immunoglobulin E / immunology
  • Immunoglobulin E / pharmacology*
  • Luteolin
  • Mast Cells / physiology*
  • Mast Cells / ultrastructure
  • Protein Kinase C / physiology
  • Quercetin / immunology
  • Quercetin / pharmacology*
  • Signal Transduction / drug effects


  • Flavanones
  • Flavonoids
  • Immunoglobulin E
  • baicalein
  • Quercetin
  • Protein Kinase C
  • Luteolin
  • Calcium