ABSTRACT
PURPOSE: Platycodon grandiflorum (a domestic diploid variety, DV-PG) has been used as a food and component of various traditional oriental medicines. Although DV-PG is known to have an anti-allergic effect, little is known about the beneficial health effects of the tetraploid ‘Etteum’ variety in the Platycodon grandiflorum (TV-PG), which is a recently developed variety. In this study, we investigated the effect of TV-PG on the rat basophilic leukemia mast cell (RBL-2H3)-mediated allergic response. METHODS: To examine the effects of TV-PG on the allergic response, RBL-2H3 cells were sensitized with dinitropheny (DNP)-immunoglobin E, treated with various concentrations of TV-PG, and challenged with DNP-human serum albumin. We estimated cell granulation by measuring the release of β-hexosaminidase and production of inflammatory mediators by ELISA. RESULTS: TV-PG had no effect on the proliferation or cytotoxicity of RBL-2H3 cells within the concentration range of 0 to 200 µg/mL. TV-PG inhibited degranulation of RBL-2H3 cells by antigen stimulation in a dose-dependent manner. TV-PG also suppressed the production of inflammatory cytokines and mediators such as interleukin-4, tumor necrosis factor-α, prostagladin E2, and leukotriene B4 in RBL-2H3 cells by antigen stimulation. CONCLUSION: These results indicate that TV-PG exhibits anti-allergic activity via inhibition of degranulation as well as suppression of inflammatory mediators and cytokine release. These findings suggest that TV-PG may have potential as a preventive and therapeutic agent for the treatment of various allergic diseases.