Dietary polyunsaturated fatty acids and non‐digestible oligosaccharides reduce dermatitis in mice

Background Oral administration of specific food ingredients can modify mucosal and systemic inflammatory processes. Such food components are fatty acids or carbohydrates. Nevertheless, little is known about the impact of oral administration of polyunsaturated fatty acids (PUFA) and non-digestible oligosaccharides on allergen-induced dermatitis. Method In this pilot study, skin inflammation was induced by serial epicutaneous OVA applications in OVA-sensitized mice. In parallel, mice were fed with solid food containing arachidonic acid/docosahexaenoic acid (AA/DHA), galactooligosaccharide/polydextrose (GOS/PDX) or their combination. Skin lesions were assessed by clinical skin score, but also skin barrier parameters, immunohistochemical analyses, and local cytokine expression profile. Results Both dietary AA/DHA and GOS/PDX significantly ameliorated the severity of allergen-induced dermatitis. The clinical improvement upon oral AA/DHA and GOS/PDX supplementation was associated with a reduction in transepidermal water loss and reduced KI-67 expression in the skin. Lesional CD8+ and mast cells were reduced in all treatment groups, but appeared to be most pronounced in combined AA/DHA/GOS/PDX-treated mice. Moreover, in GOS/PDX-treated mice, IFNγ and TGFβ expression was increased in skin lesions. Conclusion Dietary supplementation with DHA/AA and GOS/PDX ameliorates symptoms of allergen-induced dermatitis and may thus be beneficial in the dietary management of human atopic eczema.