Vitamin D mediated signalling in the skin is discussed controversially for its beneficial or detrimental influence. In this study we examined various factors involved in Vitamin D-mediated signalling in a mouse model for allergic dermatitis with systemic (OVA IP) and systemic plus topical allergic sensitization (OVA IP + EC). We found that the major enzyme responsible for 1,25-Vitamin D3 synthesis, the 1-hydoxylase CYP27B1 (3,6-fold for OVA IP and 2,7-fold for OVA IP + EC), the vitamin D receptor (not altered) and the sensitive Vitamin D-mediated signalling target gene CYP24A1 (65-fold in OVA IP and 726-fold in OVA IP + EC) are upregulated after systemic and systemic plus topical allergic sensitization (OVA IP + EC). In consequence, active Vitamin D-mediated signalling is involved in systemic as well as systemic/topical allergic sensitization in mouse skin.
Keywords: Atopic dermatitis; retinoid X receptor; skin inflammation.