Nicotinamide downregulates gene expression of interleukin-6, interleukin-10, monocyte chemoattractant protein-1, and tumour necrosis factor-α gene expression in HaCaT keratinocytes after ultraviolet B irradiation

Clin Exp Dermatol. 2013 Mar;38(2):185-8. doi: 10.1111/ced.12018.


Ultraviolet (UV) radiation has profound effects on human skin, causing sunburn, inflammation, cellular-tissue injury, cell death, and skin cancer. Most of these effects are mediated by a number of cytokines produced by keratinocytes. In this study we investigated whether nicotinamide (NCT), the amide form of vitamin B3, might have a protective function in reducing the expression of interleukin (IL)-1β, IL-6, IL-8, IL-10, monocyte chemoattractant protein (MCP)-1 and tumour necrosis factor (TNF)-α in UV-irradiated keratinocytes. HaCaT cells were treated with UVB in the presence or absence of NCT, and cytokine mRNA levels were examined by quantitative real-time PCR. NCT significantly downregulated IL-6, IL-10, MCP-1 and TNF-α mRNA expression, whereas it did not exert any significant effect on IL-1β or IL-8 expression. Because of its ability to decrease these cytokine mediators after UV exposure, NCT is a possible therapy to improve or prevent conditions induced or aggravated by UV light.

MeSH terms

  • Chemokine CCL2 / genetics
  • Cytokines / metabolism*
  • Down-Regulation
  • Gene Expression Profiling
  • Humans
  • Interleukin-10 / genetics
  • Interleukin-6 / genetics
  • Keratinocytes / drug effects*
  • Keratinocytes / metabolism
  • Keratinocytes / radiation effects
  • Niacinamide / pharmacology*
  • RNA, Messenger / metabolism
  • Real-Time Polymerase Chain Reaction
  • Skin / drug effects
  • Skin / metabolism
  • Skin / radiation effects
  • Tumor Necrosis Factor-alpha / genetics
  • Ultraviolet Rays
  • Vitamin B Complex / pharmacology*


  • Chemokine CCL2
  • Cytokines
  • Interleukin-6
  • RNA, Messenger
  • Tumor Necrosis Factor-alpha
  • Vitamin B Complex
  • Interleukin-10
  • Niacinamide