Suppression of leukotriene B ₄ production is involved in the anti-pruritic action of Grifola frondosa in pollen allergy-induced ocular itching in mice

Abstract

Grifola frondosa (G. frondosa) is an edible mushroom consumed as a health food in Asia that has recently been reported to have antiallergic effects. In this study, we investigated the effects of G. frondosa on pollen allergy-induced ocular itching in mice. G. frondosa was boiled and freeze-dried (heat-treated G. frondosa). Oral administration of heat-treated G. frondosa (0.1 and 1 g/kg) suppressed pollen allergy-induced ocular itching and plasma extravasation but not histamine-induced plasma extravasation. Oral administration of ergosterol, an active ingredient in G. frondosa (5 and 50 mg/kg), or zileuton (100 mg/ kg), which is an inhibitor of 5-lipoxygenase (the main enzyme required for leukotriene B 4 production), inhibited pollen allergyinduced ocular itching. In addition, ergosterol inhibited antigeninduced leukotriene B 4 production in mast cells. These findings suggest that G. frondosa and its active ingredient ergosterol prevent pollen allergy-induced itching through the inhibition of leukotriene B 4 production in mast cells.

Potential Beneficial Effects and Pharmacological Properties of Ergosterol, a Common Bioactive Compound in Edible Mushrooms

“…Similarly, both the ergosterol-rich extract of Grifola frondosa and pure ergosterol inhibit histamine release in air pouch-type allergic inflammation and reduce vascular permeability and edema in mice [ 24 , 25 ]. The extract of edible mushroom Grifola frondosa and its ergosterol also prevent pollen-allergy-induced ocular itching in mice by suppressing leukotriene B 4 production in mast cells [ 70 ].…”