Caffeic acid phenethyl ester attenuates IgE-induced immediate allergic reaction

Caffeic acid phenethyl ester (CAPE) is the active component of honey bee propolis extracts. The results of the current study demonstrate that CAPE attenuated immunoglobulin (Ig)E-mediated allergic response in mast cells. Oral administration of CAPE inhibited IgE-mediated passive cutaneous anaphylaxis. CAPE effectively reduced both histamine and serotonin (5-HT)-induced vascular permeability in rats. CAPE also reduced histamine and leukotrienes (LTs) release from isolated rat peritoneal mast cells. Moreover, CAPE suppressed contraction induced by histamine (3 × 10⁻⁸–3 × 10⁻⁵ M), 5-HT (3 × 10⁻⁹–10⁻⁶ M) and adenosine (3 × 10⁻⁸–10⁻⁵ M) in guinea pig tracheal zigzag. These findings provide evidence that CAPE may serve as an effective therapeutic agent for allergic diseases.