Synergistic anti-allergy activity using a combination of Enterococcus faecalis IC-1 and luteolin

Abstract

Abstract Allergies are a global issue. However, medical intervention for allergy treatment is limited. Recent studies have focused on allergy prevention with food components. Both the lactic acid bacteria Enterococcus faecalis IC-1 (IC-1) and the flavonoid luteolin have been shown to have an anti-allergic effect. Following the concept of diet diversity and synergistic effects, the purpose of this study was to explore the anti-allergic activity of a combination of IC-1 and luteolin. A combination of IC-1 and luteolin had anti-allergic effects with the passive cutaneous anaphylaxis reaction and strongly inhibited mast cell degranulation in a Caco-2/RBL-2H3 cells co-culture system. Oral administration with a combination of IC-1 and luteolin significantly decreased blood IgE content in ovalbumin (OVA)-induced allergic mice and alleviated symptoms of an allergy attack. These might have been done through correcting Th2 shifting with the allergy state since a combination of IC-1 and luteolin increased the IFN-γ content in blood. Furthermore, in vitro differentiation of the Th2 subset confirmed that a combination of IC-1 and luteolin inhibited naive T cell from differentiating into a Th2 subset through inhibition of Th2 transcription factor GATA-3 expression. The combination also promoted the gene expression level of IFN-γ in mice bone marrow-derived dendritic cells. These results suggested a synergistic anti-allergic effect using a combination of IC-1 and luteolin both in reducing IgE content and in inhibiting mast cell degranulation during the allergy state.