Effect of prednisolone on the fatty acid composition and the formation of arachidonate metabolites in human keratinocytes in culture.
Human keratinocytes were cultured for eight days in a medium containing 0 - 100 microM of prednisolone. Subsequently, the amounts of prostaglandin F2 alpha (PGF2 alpha), 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), and thromboxane B2 (TXB2) released into the culture medium were measured by radioimmunoassay and the fatty acid composition of the keratinocytes was investigated. Prednisolone significantly inhibited the production of PGF2 alpha and 6-keto-PGF1 alpha by keratinocytes whereas the formation of TXB2 remained unaffected. The total molar formation of the cyclo-oxygenase metabolites of arachidonic acid appeared to be inhibited by prednisolone, suggesting that prednisolone might interfere with the phospholipase activities and the release of arachidonic acid in human keratinocytes. Prednisolone had only a weak effect on the fatty acid composition of keratinocytes as the percentage amount of oleic acid (18:1) was slightly decreased and that of eicosenoic acid (20:1) correspondingly increased while the percentage amounts of the other fatty acids remained unaffected. The present study might suggest that the anti-inflammatory action of glucocorticoids in the human skin would at least in part be due to the decreased production of cyclo-oxygenase metabolites of arachidonic acid in human keratinocytes. The present investigation also suggests that prolonged glucocorticoid treatment of the skin would not cause changes in the fatty acid composition of keratinocytes.
D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D002478:Cells, Cultured; D005227:Fatty Acids / Q000032:analysis*; D006801:Humans; D011239:Prednisolone / Q000494:pharmacology*; D011453:Prostaglandins / Q000096:biosynthesis; D012867:Skin / Q000032:analysis / Q000187:drug effects / Q000378:metabolism*
D001095:Arachidonic Acids; D005227:Fatty Acids; D011453:Prostaglandins; D016718:Arachidonic Acid; D011239:Prednisolone