Narrowband ultraviolet B treatment improves vitamin D balance and alters antimicrobial peptide expression in skin lesions of psoriasis and atopic dermatitis

Br J Dermatol. 2010 Aug;163(2):321-8. doi: 10.1111/j.1365-2133.2010.09767.x. Epub 2010 Mar 17.

Abstract

Background: Narrowband ultraviolet B (NB-UVB) is a routine treatment for psoriasis and atopic dermatitis (AD) but its effect on vitamin D balance is not well studied.

Objectives: To examine whether NB-UVB treatment in winter improves vitamin D balance in psoriasis and AD, and to study the effects of NB-UVB on antimicrobial peptide and cytokine expression in the skin.

Methods: Eighteen adult patients with psoriasis, 18 with AD and 15 healthy subjects received a total of 15 NB-UVB exposures on the whole body, given three times a week. Serum calcidiol (25-hydroxyvitamin D) was measured by radioimmunoassay. Antimicrobial peptide and cytokine expression in skin lesions was examined by real-time quantitative polymerase chain reaction.

Results: At onset 16 (89%) patients with psoriasis, 17 (94%) patients with AD and eight (53%) healthy subjects had vitamin D insufficiency (calcidiol < 50 nmol L(-1)). NB-UVB treatment significantly increased (P < 0.001) serum calcidiol. The increase was 59.9 nmol L(-1) (95% confidence interval, CI 53.5-66.9) in psoriasis, 68.2 nmol L(-1) (95% CI 55.4-80.1) in AD and 90.7 nmol L(-1) (95% CI 63.8-123.4) in healthy subjects. Psoriasis Area and Severity Index and SCORAD improved significantly (P < 0.001) but no correlation to the increase of serum calcidiol was found. Cathelicidin and human beta-defensin 2 (HBD2) expression was high in skin lesions of psoriasis. After six NB-UVB treatments cathelicidin increased further while HBD2 expression decreased. A similar trend was observed in AD lesions. NB-UVB caused a marked but nonsignificant decrease of interleukin (IL)-1beta and IL-17 in psoriasis lesions.

Conclusions: The present study shows that in addition to a significant improvement of psoriasis and AD, NB-UVB treatment effectively corrects vitamin D insufficiency. It also increases cathelicidin and decreases HBD2 levels in healing skin lesions of psoriasis and AD. This effect might be mediated by improved vitamin D balance and the local cytokine network.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antimicrobial Cationic Peptides / metabolism*
  • Calcifediol / blood*
  • Cathelicidins / metabolism
  • Cytokines / metabolism
  • Dermatitis, Atopic / metabolism
  • Dermatitis, Atopic / radiotherapy*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Psoriasis / metabolism
  • Psoriasis / radiotherapy*
  • Radioimmunoassay
  • Reverse Transcriptase Polymerase Chain Reaction
  • Seasons
  • Ultraviolet Therapy / methods*
  • Vitamin D / metabolism
  • Vitamin D / radiation effects*
  • beta-Defensins / metabolism

Substances

  • Antimicrobial Cationic Peptides
  • Cathelicidins
  • Cytokines
  • DEFB4A protein, human
  • beta-Defensins
  • Vitamin D
  • Calcifediol