Stimulation of human melanocytes by vitamin D3 possibly mediates skin pigmentation after sun exposure.
We found an increased amount of immunoreactive tyrosinase in human melanocytes after 6-d culturing with vitamin D3 (cholecalciferol). Most of these melanocytes became more dendritic and swollen in a fashion similar to that noted in the skin after ultraviolet irradiation. However, 7-dehydrocholesterol (pro-vitamin D3) or 1 alpha,25-dihydroxy-vitamin D3 (activated vitamin D3) were found to have little effect on the same system. Because vitamin D3 is known to be photochemically converted from pro-vitamin D3 in the skin by ultraviolet irradiation, the mechanism of human skin pigmentation after ultraviolet irradiation, thus far unknown, may be at least partly explained by this stimulating effect of vitamin D3 on melanocytes.
Tomita
Y
Y
Department of Dermatology, Tohoku University School of Medicine, Sendai, Japan.
Torinuki
W
W
Tagami
H
H
D002762:Cholecalciferol / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008544:Melanocytes / Q000187:drug effects* / Q000528:radiation effects / Q000648:ultrastructure; D014442:Monophenol Monooxygenase / Q000032:analysis; D012880:Skin Pigmentation / Q000187:drug effects* / Q000528:radiation effects; D014466:Ultraviolet Rays
D002762:Cholecalciferol; D014442:Monophenol Monooxygenase