Paeoniflorin inhibits IgE-mediated allergic reactions by suppressing the degranulation of mast cells though binding with FcɛRI alpha subunits. - GreenMedInfo Summary

Paeoniflorin (PF), a monoterpene glycoside isolated from the aqueous extract of the Chinese herb Radix Paeoniae Alba, has been used for treating various inflammatory diseases. In this study, we aimed to investigate the anti-allergic activities of PF. The anti-anaphylactic activity of PF was investigated using mast cell (MC) degranulation assay as well as Cainflux in vitro and skin swelling and extravasation assays in vivo. The results showed that PF inhibited MC degranulation (histamine release from 74.5 ± 4.95 ng/ml to 58.7 ± 6.06 ng/ml) and Cainflux challenged by DNP-BSA in vitro. In addition, PF reduced the degree of swelling and Evans blue exudation in mice paws. Furthermore, PF dose-dependently reduced serum inflammatory mediator release in mice sensitized with ovalbumin for 48 h by inhibiting MC degranulation. Molecular docking study revealed that PF bound better with the α subunit of FcɛRI than with the β subunit. SPR revealed that PF had a strong affinity interaction with FcɛRI α subunit and the Kvalue was (7.08 ± 0.97) e-6 M. Our findings revealed that PF inhibited anaphylactic responses in vivo and in vitro, and it can be considered a novel FcɛRI inhibitor for preventing MC-related allergic diseases.