title: Vitamin D Receptor Expression in Vitiligo.
abstract: BACKGROUND
  Vitiligo is a progressive depigmenting disorder characterized by loss of functional melanocytes from the epidermis. The etiopathogenesis of vitiligo is still unclear. Vitamin D has stimulatory effects on melanocytes and acts through its nuclear Vitamin D receptor (VDR) on target cells.
  
  
  OBJECTIVE
  The purpose of this study was to declare the role of Vitamin D in the pathogenesis of vitiligo.
  
  
  METHODS
  This case-control study included 30 vitiligo patients and 30 age, gender-matched healthy controls. Blood samples were withdrawn from the study subjects, and the serum 25(OH) D level was determined by an enzyme-linked immunosorbent assay technique. Serum 25(OH) D levels were divided into: Normal or sufficient (≥30 ng/ml), insufficient (< 30-> 20ng/ml), and deficient (≤20 ng/ml) levels. Skin biopsies were obtained from the depigmented lesions and clinically normal skin of vitiligo patients and from the controls, and VDR gene expression was determined using real-time polymerase chain reaction.
  
  
  RESULTS
  Only 10 patients with vitiligo (33.3%) had sufficient serum 25(OH) D levels (≥30 ng/ml), 12 patients (40%) had insufficient levels, and 8 patients (26.7%) had deficient levels. On the other hand, most of the controls (96.7%) had sufficient levels. The mean serum 25(OH) D level in patients was significantly decreased compared to controls (P < 0.001). The VDR-mRNA expression was also significantly decreased in lesional and nonlesional skin of patients compared to controls (P < 0.001, P < 0.001, respectively).
  
  
  CONCLUSIONS
  Vitamin D deficiency influences the extent of vitiligo and could contribute to the pathogenesis of vitiligo through its immunomodulatory role and its role in melanogenesis.
authors.affiliation: Department of Dermatology, Faculty of Medicine, Beni-Suef University, Beni-Suef, Egypt.
authors.forename: Reham William
authors.initials: RW
authors.lastname: Doss
authors.affiliation: Department of Dermatology, Faculty of Medicine, Beni-Suef University, Beni-Suef, Egypt.
authors.forename: Abdel-Aziz
authors.initials: AA
authors.lastname: El-Rifaie
authors.affiliation: Department of Dermatology, Faculty of Medicine, Beni-Suef University, Beni-Suef, Egypt.
authors.forename: Yasser M
authors.initials: YM
authors.lastname: Gohary
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Cairo University, Cairo, Egypt.
authors.forename: Laila A
authors.initials: LA
authors.lastname: Rashed
keywords: 25-hydroxy Vitamin D; Vitamin D receptor; Vitiligo; enzyme-linked immunosorbent assay; real-time polymerase chain reaction