title: Vitamin D: a calciotropic hormone regulating calcium-induced keratinocyte differentiation.
abstract: BACKGROUND
  Most biologically active forms of vitamin D3 (1,25(OH)2D3) and its analogs have functions and therapeutic potential that extend beyond those of regulating bone mineralization and intestinal calcium transport.
  
  
  OBJECTIVE
  We attempt to provide the rationale for the effectiveness of 1,25(OH)2D3 and its analogs in dermatology.
  
  
  METHODS
  The recent literature on the mechanisms of action of 1,25(OH)2D3 were reviewed.
  
  
  RESULTS
  1,25(OH)2D3 affects keratinocyte differentiation partly through its regulation of epidermal responsiveness to calcium. Calcium and 1,25(OH)2D3 interact in transcription of the genes required for differentiation and in the stability of the mRNAs produced from such genes.
  
  
  CONCLUSIONS
  An understanding of these mechanisms provides a rationale for treatment of various skin diseases with 1,25(OH)2D3 and its analogs and directs development of more effective therapy.
authors.affiliation: University of California, Veterans Affairs Medical Center Endocrine Research, San Francisco 94121, USA.
authors.forename: D D
authors.initials: DD
authors.lastname: Bikle
mesh_terms: D002113:Calcification, Physiologic / Q000502:physiology; D002117:Calcitriol / Q000031:analogs & derivatives / Q000494:pharmacology / Q000502:physiology* / Q000627:therapeutic use; D002118:Calcium / Q000378:metabolism / Q000502:physiology*; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D002762:Cholecalciferol / Q000031:analogs & derivatives / Q000502:physiology / Q000627:therapeutic use; D003879:Dermatologic Agents / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D012867:Skin / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D012871:Skin Diseases / Q000188:drug therapy; D014158:Transcription, Genetic
chemical_list: D003879:Dermatologic Agents; D012333:RNA, Messenger; D002762:Cholecalciferol; D002117:Calcitriol; D002118:Calcium