抄録・内容(英) | Background : Recently, a new atopic dermatitis (AD) mouse model was reported; after feeding hairless mice with a special low magnesium diet (HR-AD), they developed dry skin (low skin water content and high transepidermal water loss (TEWL)) and elevated blood immunoglobulin E levels (IgE) with 100% repeatability. Therefore, this model was used for therapeutic research regarding AD. However, to determine the mechanism by which HR-AD induces AD-like symptoms, the relationships between low magnesium, essential fatty acids (EFA), and lipid composition need to be clarified. / Methods : First, to clarify whether the low magnesium of HR-AD induces AD-like symptoms, hairless mice were fed HR-AD or magnesium-supplemented HR-AD. They were evaluated based on TEWL values, an in vivo water sorption-desorption test, water intake, serum IgE levels, histological examination, and macroscopic observation. Second, to investigate whether the EFA deficiency in HR-AD induces AD-like symptoms, hairless mice that had previously developed ADlike symptoms were fed olive oil-soaked HR-AD. Finally, the lipid composition of HR-AD was analyzed by gas chromatography. / Results : Comparing with the HR-AD group revealed that magnesium supplementation did not compensate for any skin symptoms. However, feeding with olive oil-soaked HR-AD for 3 days dramatically cured the AD-like symptoms. On re-feeding with HR-AD, the AD-like symptoms were recovered. Lipid analysis revealed that HR-AD did not contain linoleic and linolenic acids. / Conclusions : We clarified that latent EFA deficiency but not magnesium deficiency induces AD-like symptoms in the new AD mouse model following HR-AD feeding. |