Leukotrienes and Other Lipoxygenase Products in the Pathogenesis and Therapy of Psoriasis and Other Dermatoses

In this issue of theArchives(page 548), Kragballe and Herlin describe a double-blind study that clearly demonstrates that benoxaprofen is efficacious in the therapy of psoriasis. This exciting observation may have a substantial impact on drug development for psoriasis and possibly other inflammatory proliferative skin diseases. My purpose is to present evidence that has caused me to conclude that the observations of Kragballe and Herlin are of unusual importance. This evidence will be understood best if it is presented in the context of current information on arachidonic acid (AA) transformations in the epidermis and in whole skin. AA TRANSFORMATIONS Arachidonic acid, an unsaturated fatty acid, is the precursor of prostaglandins (PGs), hydroxyeicosatetraenoic acids (HETEs), thromboxanes (TXs), and leukotrienes (LTs).1The backbone of lecithin is glycerol with its three carbon atoms. Arachidonic acid is esterified to the middle (the so-called 2 position) of these three atoms in epidermal lecithin