title: Assessment of vitamin D receptors in alopecia areata and androgenetic alopecia.
abstract: BACKGROUND
  Alopecia areata (AA) is a frequent autoimmune disease, the pathogenesis of which is still unknown. Androgenetic alopecia (AGA) is a noncicatricial type of patterned hair loss. Expression of vitamin D receptors (VDRs) on keratinocytes is essential for maintenance of normal hair cycle, especially anagen initiation.
  
  
  OBJECTIVE
  To assess VDRs in the skin and blood of AA and AGA patients, in order to evaluate their possible role in these hair diseases.
  
  
  METHODS
  This study recruited 20 patients with AA, 20 patients with AGA, and 20 healthy controls. Blood samples and lesional scalp biopsies were taken from all participants for detection of VDR levels.
  
  
  RESULTS
  Serum and tissue VDR levels were lower in AA as well as AGA patients when compared to controls (P = 0.000). Serum and tissue VDR were positively correlated in each group. Tissue VDR was significantly lower in female patients with AA than males (P = 0.046) although serum and tissue VDR levels were significantly higher in female AGA patients than males (P = 0.004).
  
  
  CONCLUSIONS
  This study suggests an important role for VDR in the pathogenesis of AA and AGA through documenting lower serum and tissue VDR levels in AA and AGA patients in comparison with controls.
authors.affiliation: Department of Dermatology, Cairo University, Cairo, Egypt.
authors.forename: Marwa M T
authors.initials: MM
authors.lastname: Fawzi
authors.affiliation: Department of Dermatology, Cairo University, Cairo, Egypt.
authors.forename: Sara Bahaa
authors.initials: SB
authors.lastname: Mahmoud
authors.affiliation: Dermatology Department, Bolak El Dakror Hospital, Cairo, Egypt.
authors.forename: Shereen Fathi
authors.initials: SF
authors.lastname: Ahmed
authors.affiliation: Biochemistry, Faculty of Medicine, Cairo University, Cairo, Egypt.
authors.forename: Olfat Gamil
authors.initials: OG
authors.lastname: Shaker
mesh_terms: D000293:Adolescent; D000328:Adult; D000505:Alopecia / Q000378:metabolism; D000506:Alopecia Areata / Q000097:blood / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018167:Receptors, Calcitriol / Q000097:blood / Q000378:metabolism*; D012737:Sex Factors; D055815:Young Adult
chemical_list: D018167:Receptors, Calcitriol
keywords: alopecia areata; androgenetic alopecia; vitamin D receptors