1 alpha,25-dihydroxyvitamin D-3; Its role for homeostasis of keratinocytes

Epidermal homeostasis is influenced by a number of hormones and regulative growth factors that are maintained by a tightly regulated balance between cell proliferation, cell differentiation, and cell death. Vitamin D is one of those regulatory factors. It has recently been demonstrated that 1 alpha,25-dihydroxyvitamin D-3 (1 alpha 25(OH)(2)D-3) takes part in the regulation of the cell cycle by multiple and complex functions. This review discuses 1 alpha,25(OH)(2)D-3 and its analogues in connection with the renewal of epidermal keratinocytes as well as the molecular mechanisms underlying terminal differentiation or rather programmed cell death. Furthermore, interest is focused on the possible clinical application of vitamin D-3 analogues. (C) Elsevier Science Inc. 1996