A cytochrome P450 monooxygenase involved in the metabolism of retinoids and eicosanoids (, ). In epidermis, may contribute to the oxidative metabolism of all-trans-retinoic acid. For this activity, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (NADPH--hemoprotein reductase) . Additionally, displays peroxidase and isomerase activities toward various oxygenated eicosanoids such as prostaglandin H2 (PGH2) and hydroperoxyeicosatetraenoates (HPETEs) . Independently of cytochrome P450 reductase, NADPH, and O2, catalyzes the breakdown of PGH2 to hydroxyheptadecatrienoic acid (HHT) and malondialdehyde (MDA), which is known to act as a mediator of DNA damage .
Subcellular locations: Endoplasmic reticulum membrane, Microsome membrane
Expressed at higher levels in extrahepatic tissues including trachea, lung, stomach, small intestine, colon, kidney, breast, placenta and spleen (, ). Expressed in peripheral blood leukocytes . Constitutively expressed in skin (at protein level) .