Improvement of atopic dermatitis and reduction of skin allergic responses by oral intake of konjac ceramide.

Although topical application of ceramide is effective in the treatment of atopic dermatitis, its effect is transient. Thus, the effect of oral intake of ceramide on atopic dermatitis was studied. Two groups of 25 children with moderate atopic dermatitis, who were allergic to house dust mite took either milk sugar (control group) or 1.8 mg/day of konjac ceramide in milk sugar (ceramide group) once a day for 2 weeks. Before and after 2 weeks, skin symptoms were assessed using the SCORAD index, while allergic skin responses to house dust mite were assessed by skin prick test. Moreover, production of allergen-specific IgE and various cytokines by mononuclear cells was measured. After 2 weeks, SCORAD index score, allergic skin responses to house dust mite and house dust mite-specific IgE production were significantly reduced in the ceramide group, but not in the control group. Moreover, house dust mite-induced cytokine production was skewed towards the Th1 type, since production of Th1 cytokine, IFN-gamma, and IL-12, was increased, while production of Th2 cytokine, IL-4, and IL-13, was decreased. In contrast, no change of these parameters was found in control group. Collectively, oral intake of konjac ceramide improved skin symptoms and reduced allergic responses with concomitant skewing of the cytokine pattern towards the Th1 type.