5-Lipoxygenase activation in psoriasis: a dead issue?

Skin Pharmacol. 1993;6(4):292-7. doi: 10.1159/000211152.


It has been suggested in the literature that 5-lipoxygenase activation may be an important pathological event in psoriasis and that 5-lipoxygenase inhibitors may thus have some beneficial therapeutic effect in this disease. This is because (1) neutrophil activation is a prominent feature of the disease, (2) leukotriene B4 is a potent chemotactic agent for neutrophils and is present in psoriatic lesions, (3) 5-lipoxygenase is present in human epidermis, (4) inhibition of 5-lipoxygenase may affect the disease. These concepts are questioned, and in particular it is suggested that (1) the leukotriene B4-like material found in psoriatic skin has never been shown to have the correct stereochemistry to indicate that it is 5-lipoxygenase derived, (2) there is no convincing evidence for the presence of the 5-lipoxygenase enzyme in human skin, (3) drugs purported to have some benefit in psoriasis through 5-lipoxygenase inhibitory mechanisms act through other mechanisms and (4) selective leukotriene biosynthesis inhibitors have no therapeutic utility in psoriasis. It is concluded that 5-lipoxygenase activation does not play a significant role in the pathology of psoriasis and therefore selective leukotriene biosynthesis inhibitors would have no significant role in the treatment of this disease.

Publication types

  • Review

MeSH terms

  • Arachidonate 5-Lipoxygenase / physiology*
  • Cell Movement / drug effects
  • Epidermis / enzymology
  • Humans
  • Leukotriene Antagonists*
  • Leukotriene B4 / physiology
  • Neutrophils / drug effects
  • Psoriasis / drug therapy
  • Psoriasis / enzymology*
  • Psoriasis / pathology


  • Leukotriene Antagonists
  • Leukotriene B4
  • Arachidonate 5-Lipoxygenase