| [ Summary ] |
It has been well known that ultraviolet promotes the synthesis of vitamin D in the skin. Recently, the effectiveness of vitamin D ointment on psoriasis has been proven. This indicates that epidermal cells are the target of vitamin D3. We studied the mechanism of the effect of vitamin D3 on epidermal cells. Vitamin D3 the growth of epidermal cells and promotes epidermal differentiation. Furthermore, Rb protein was involved in the growth inhibition pathway by vitamin D3. We also found that vitamin D3 increases the production of TGF-beta which inhibits epidermal cell growth. Finally, the expression of vitamin D receptor was examined. Epidermal cells, fibroblasts and melanocytes expressed vitamin D receptor confirmed by Western blot. These data indicate that vitamin D has a profound effect on the skin. |