title: Vitamin D3 analogs stimulate hair growth in nude mice.
abstract: The active form of vitamin D3 can regulate epidermal keratinization by inducing terminal differentiation; and mice lacking the vitamin D receptor display defects leading to postnatal alopecia. These observations implicate the vitamin D3 pathway in regulation of hair growth. We tested the ability of 1,25 dihydroxyvitamin D3 and its synthetic analogs to stimulate hair growth in biege/nude/xid (BNX) nu/nu (nude) mice exhibiting congenital alopecia. Nude mice were treated with different vitamin D3 analogs at doses that we had previously found to be the highest dose without inducing toxicity (hypercalcemia). The mice were monitored for hair growth and were scored according to a defined scale. Skin samples were taken for histological observation of hair follicles and for extraction of RNA and protein. Vitamin D3 analogs dramatically stimulated the hair growth of nude mice, although parental 1,25 dihydroxyvitamin D3 had no effect. Hair growth occurred in a cyclical pattern, accompanied by formation of normal hair follicles and increased expression of certain keratins (Ha7, Ha8, and Hb3). Vitamin D3 analogs seem to act on keratinocytes to initiate hair follicle cycling and stimulate hair growth in mice that otherwise do not grow hair.
authors.affiliation: Cedars-Sinai Medical Center/University of California Los Angeles School of Medicine, Los Angeles, California 90048, USA.
authors.forename: Vijaya
authors.initials: V
authors.lastname: Vegesna
authors.forename: James
authors.initials: J
authors.lastname: O'Kelly
authors.forename: Milan
authors.initials: M
authors.lastname: Uskokovic
authors.forename: Jonathan
authors.initials: J
authors.lastname: Said
authors.forename: Nathan
authors.initials: N
authors.lastname: Lemp
authors.forename: Takayuki
authors.initials: T
authors.lastname: Saitoh
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ikezoe
authors.forename: Lise
authors.initials: L
authors.lastname: Binderup
authors.forename: H Phillip
authors.initials: HP
authors.lastname: Koeffler
mesh_terms: D000505:Alopecia / Q000188:drug therapy / Q000235:genetics; D000818:Animals; D002117:Calcitriol / Q000494:pharmacology; D002762:Cholecalciferol / Q000031:analogs & derivatives*; D005260:Female; D006197:Hair / Q000187:drug effects* / Q000254:growth & development*; D018859:Hair Follicle / Q000187:drug effects / Q000502:physiology; D015603:Keratinocytes / Q000187:drug effects / Q000502:physiology; D007633:Keratins / Q000032:analysis; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D012867:Skin / Q000033:anatomy & histology / Q000737:chemistry
chemical_list: D002762:Cholecalciferol; D007633:Keratins; D002117:Calcitriol