Phellinus linteus Grown on Germinated Brown Rice Inhibits IgE-Mediated Allergic Activity through the Suppression of FcεRI-Dependent Signaling Pathway In Vitro and In Vivo

Abstract EN

Phellinus linteus (PL) has been used as a traditional herbal medicine owing to its immune regulatory activity.

Previous studies reported that PL grown on germinated brown rice (PBR) exerted immunomodulatory, anticancer, and anti-inflammatory activities.

However, role of PBR on type I hypersensitive reactions has not been studied yet.

We found that PBR contained more polyphenolic compounds than PL extract.

Among fractions, PBR butanol fraction (PBR-BuOH) significantly contained the most amounts of total polyphenolic contents compared with all extracts or fractions.

In this study, anti-allergic activity of PBR-BuOH was examined using in vitro and in vivo models of immunoglobulin E/antigen- (IgE/Ag-) stimulated allergy.

The inhibitory activity of degranulation was higher in PBR-BuOH (IC50 41.31 ± 0.14 μg/mL) than in PL-BuOH (IC50 108.07 ± 8.98 μg/mL).

We observed that PBR-BuOH suppressed calcium influx and the level of TNF-α and IL-4 mRNA expression in a dose-dependent manner.

The phosphorylation of Fyn, Gab2, PI3K, Syk, and IκB protein is reduced by PBR-BuOH.

Oral administration of PBR-BuOH inhibited allergic reactions including the extravasation of Evans blue dye, ear swelling, and infiltration of immune cells in mice with passive cutaneous anaphylaxis (PCA).

These findings suggest that PBR-BuOH might be used as a functional food, a health supplement, or a drug for preventing type I hypersensitive allergic disease.