Prostaglandin-E2 is produced by adult human epidermal melanocytes in response to UVB in a melanogenesis-independent manner

Pigment Cell Melanoma Res. 2010 Jun;23(3):394-403. doi: 10.1111/j.1755-148X.2010.00696.x. Epub 2010 Mar 17.

Abstract

Excessive ultraviolet radiation (UVR) exposure induces erythema, mediated in part by prostaglandin-E(2) (PGE(2)). While keratinocytes are a major PGE(2) source, epidermal melanocytes (EM) also express PGE(2)-production machinery. It is unclear whether EM-produced PGE(2) contributes to UVR-induced skin inflammation, and whether this is correlated with melanogenesis. Epidermal melanocytes were cultured from skin phototype-1 and -4 donors, followed by assessment of PGE(2) production and melanogenesis. Epidermal melanocytes expressed cytoplasmic phospholipase-A(2), cyclooxygenase-1, cytoplasmic prostaglandin-E synthase and microsomal prostaglandin-E synthase-1, -2. Epidermal melanocytes produced PGE(2) under basal conditions, which increased further after arachidonic acid stimulation. Epidermal melanocytes expressed cyclooxygenase-2 (COX-2) mRNA and a selective COX-2 inhibitor (NS-398) reduced PGE(2) production. Ultraviolet B-induced PGE(2) production was positively correlated with skin phototype-1, despite variability between individual EM donors. By contrast, there was no correlation between PGE(2) production by EM and their melanogenic status. Thus, EM may contribute to UVR-induced erythema, with role of donor skin phototype more important than their melanogenic status.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Arachidonic Acid / pharmacology
  • Dinoprostone / biosynthesis*
  • Epidermal Cells*
  • Female
  • Humans
  • Hydrogen Peroxide / pharmacology
  • Indomethacin / pharmacology
  • Intramolecular Oxidoreductases / metabolism
  • Keratinocytes / drug effects
  • Keratinocytes / metabolism
  • Keratinocytes / radiation effects
  • Male
  • Melanins / biosynthesis*
  • Melanocytes / drug effects
  • Melanocytes / enzymology
  • Melanocytes / metabolism*
  • Melanocytes / radiation effects*
  • Membrane Glycoproteins / metabolism
  • Monophenol Monooxygenase / metabolism
  • Nitrobenzenes
  • Oxidoreductases / metabolism
  • Sulfonamides
  • Ultraviolet Rays*
  • Young Adult

Substances

  • Melanins
  • Membrane Glycoproteins
  • Nitrobenzenes
  • Sulfonamides
  • N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide
  • Arachidonic Acid
  • Hydrogen Peroxide
  • Oxidoreductases
  • TYRP1 protein, human
  • Monophenol Monooxygenase
  • Intramolecular Oxidoreductases
  • dopachrome isomerase
  • Dinoprostone
  • Indomethacin