Occurrence of hepoxilins and trioxilins in psoriatic lesions

We recently found that normal human epidermis produces relatively high amounts of hepoxilins and trioxilins in vitro. Therefore, the aim of this study was to demonstrate the presence of these compounds in psoriatic lesions. Extracts front scales of patients with chronic stable plaque psoriasis were analyzed by a combination of high performance liquid chromatography and gas chromatography-mass spectrometry techniques, We found that the levels of hepoxilin B-3 were more than 16-fold higher in psoriatic scales than in normal epidermis (3.2 +/- 2.3 and < 0.2 ng per mg, respectively), whereas hepoxilin A(3) was not detected in ally sample, Trioxilins were semiquantitated and referred to 12-hydroxyeicosatetraenoic acid, ratios of trioxilins A(3) and B-3 12-hydroxyeicosatetraenoic acid in psoriatic lesions were 0.65 +/- 0.23 and 0.32 +/- 0.28, respectively, and they were not detected in normal epidermis, The presence of a great amount of trioxilin A(3) strongly suggests that hepoxilin A(3) was present in psoriatic lesions and it was totally degraded to trioxilin A(3), during the analysis procedure, Our results demonstrate that hepoxilins and trioxilins are produced by human skin in vivo and that the levels of these compounds are increased in psoriasis, The reported biologic activities of hepoxilins indicate that they could amplify and maintain the inflammatory response, Our results reinforce the idea that these compounds could play a role as mediators in the inflammatory response in skin, particularly in psoriasis.