Prostaglandin-E2 is produced by adult human epidermal melanocytes in response to UVB in a melanogenesis-independent manner.
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.
Centre for Skin Sciences, School of Life Sciences, University of Bradford, Bradford, UK.
Karl
K
Gledhill
Lesley E
LE
Rhodes
Margaret
M
Brownrigg
Ann K
AK
Haylett
Mojgan
M
Masoodi
Anthony J
AJ
Thody
Anna
A
Nicolaou
Desmond J
DJ
Tobin
D000328:Adult; D016718:Arachidonic Acid / Q000494:pharmacology; D015232:Dinoprostone / Q000096:biosynthesis*; D000078404:Epidermal Cells; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007213:Indomethacin / Q000494:pharmacology; D019746:Intramolecular Oxidoreductases / Q000378:metabolism; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D008297:Male; D008543:Melanins / Q000096:biosynthesis*; D008544:Melanocytes / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism* / Q000528:radiation effects*; D008562:Membrane Glycoproteins / Q000378:metabolism; D014442:Monophenol Monooxygenase / Q000378:metabolism; D009578:Nitrobenzenes; D010088:Oxidoreductases / Q000378:metabolism; D013449:Sulfonamides; D014466:Ultraviolet Rays; D055815:Young Adult
D008543:Melanins; D008562:Membrane Glycoproteins; D009578:Nitrobenzenes; D013449:Sulfonamides; C080955:N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; D016718:Arachidonic Acid; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; C489799:TYRP1 protein, human; D014442:Monophenol Monooxygenase; D019746:Intramolecular Oxidoreductases; C042501:dopachrome isomerase; D015232:Dinoprostone; D007213:Indomethacin