Diosgenin Attenuates Allergen-Induced Intestinal Inflammation and IgE Production in a Murine Model of Food Allergy

Diosgenin, the major sapogenin contained in the Chinese yam, has recently been shown to promote systemic T helper 1-type immunity in a murine model of airway hypersensitivity. In this study, we hypothesized that diosgenin might be effective in modulating food allergy. BALB/c mice were either left untreated (naive; NA) or administered daily with vehicle (VH: olive oil) and/or diosgenin (100 or 200 mg/kg) by gavage throughout the experiment. Except for the NA group, the mice were sensitized with ovalbumin (OVA) and repeatedly challenged with intragastric OVA to induce intestinal allergic responses. Diosgenin demonstrated a suppressive effect on the intestinal inflammation, including the occurrence of diarrhea, the infiltration and degranulation of mast cells, and the presence of mucin-containing goblet cells in the duodenum. A protective effect by diosgenin on reducing the crypt depth of the intestine was also observed in OVA-sensitized and challenged mice. Furthermore, the serum production of OVA-specific IgE, and the total IgE was suppressed. In contrast, OVA-specific IgG(2a) was enhanced by diosgenin treatment in OVA-sensitized mice. These results demonstrated the in vivo anti-allergic activity of diosgenin, which is associated with the suppression of IgE production and mast cell infiltration and degranulation.