Inhibitory effects of dietary resveratrol on allergic responses in mast cells and passive cutaneous anaphylaxis in mice

Abstract

Resveratrol is a polyphenol rich in the skin of red grapes and is effective in anti‐tumor and anti‐inflammation. We investigated the suppressive effects of resveratrol on IgE‐mediated allergic response in RBL‐2H3 mast cells and on passive cutaneous anaphylaxis (PCA) in mice. Mast cells sensitized with anti‐DNP‐IgE and subsequently stimulated by DNP‐HSA increased the release of β‐hexosaminidase enzyme and histamine, indicative of mast cell degranulation. This induction was diminished by nontoxic resveratrol at 1–25 μM. Western blot analysis showed that 1–25 μM resveratrol dose‐dependently mitigated the induction of FcεRI responsible for the IgE binding onto mast cells. Protein expression levels of Syk, PLCγ and PKC, all involved in allergic responses, were enhanced in activated mast cells and such levels were dampened by resveratrol. Furthermore, the Evans blue staining was evident in the ear of IgE‐mediated mice, which was diminished by oral administration of 10 mg/kg resveratrol. Edema, a usual component of most allergic reactions, apparent in the ear and dorsal skin was alleviated by resveratrol administration to IgE‐mediated mice. Taken together, the anti‐allergic responses of resveratrol suggest possible therapeutic strategies in preventing allergic diseases possibly through inhibiting mast cell degranulation and ameliorating passive cutaneous anaphylaxis.