Vitamin D3 Analogs Stimulate Hair Growth in Nude Mice

In a study from 2002, researchers investigated the effects of vitamin D3 analogs on hair growth in nude mice with congenital alopecia. The mice were treated with various doses of vitamin D3 analogs, previously determined to be non-toxic, and their hair growth was monitored and scored. The study found that while the parental compound, 1,25 dihydroxyvitamin D3, had no effect, the vitamin D3 analogs significantly stimulated hair growth in a cyclical pattern. This growth was associated with the formation of normal hair follicles and increased expression of specific keratins (Ha7, Ha8, and Hb3). The results suggest that vitamin D3 analogs may act on keratinocytes to initiate hair follicle cycling and promote hair growth in mice that are genetically predisposed to hair loss.