Human cytochrome p450 family 4 enzymes: function, genetic variation and regulation

Drug Metab Rev. 2007;39(2-3):515-38. doi: 10.1080/03602530701468573.


The microsomal cytochrome P450 (CYP) family 4 monooxygenases are the major fatty acid omega-hydroxylases. These enzymes remove excess free fatty acids to prevent lipotoxicity, catabolize leukotrienes and prostanoids, and also produce bioactive metabolites from arachidonic acid omega-hydroxylation. In addition to endogenous substrates, recent evidence indicates that CYP4 monooxygenases can also metabolize xenobiotics, including therapeutic drugs. This review focuses on human CYP4 enzymes and updates current knowledge concerning catalytic activity profiles, genetic variation and regulation of expression. Comparative differences between the human and rodent CYP4 enzymes regarding catalytic function and conditional expression are also discussed.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Cytochrome P-450 Enzyme System / biosynthesis
  • Cytochrome P-450 Enzyme System / genetics*
  • Cytochrome P-450 Enzyme System / physiology*
  • Gene Expression Regulation, Enzymologic / physiology*
  • Genetic Variation
  • Humans
  • Isoenzymes / biosynthesis
  • Isoenzymes / genetics
  • Isoenzymes / physiology
  • Rodentia


  • Isoenzymes
  • Cytochrome P-450 Enzyme System