アトピックドライスキンを発症したマウスにおけるオキサゾロン誘発皮膚炎の遷延化

抄録

Atopic dermatitis is a common, chronic skin disease. In patients with atopic dermatitis, dry skin with impaired barrier function is observed even in non-lesional areas, which is called atopic dry skin. We previously showed that atopic dry skin develops when hairless mice are fed a special diet deficient in both polyunsaturated fatty acids and starch. In this study, to clarify the impact of atopic dry skin on the development of dermatitis, we compared the degree of oxazolone-induced dermatitis between normal mice and mice with atopic dry skin. The mice were sensitized by applying 5% oxazolone solution to the abdomen for two consecutive days. After one week, 0.1% or 0.5% oxazolone solution was applied to the upper dorsal skin every other day to elicit dermatitis. Oxazolone-treated normal mice showed severe dermatitis, reduced skin hydration, impaired barrier function, and itch-related scratching behavior on days 4-14 after the challenge; however, the dermatitis symptoms spontaneously resolved on day 32, even after further repeated application of oxazolone. In contrast, in mice with atopic dry skin, oxazolone-induced dermatitis was similar to that in normal mice on days 4-14, but it was prolonged on day 32. Therefore, our results indicate that atopic dry skin is an important factor that can lead to prolonged dermatitis.