Cytochrome P450 family 7 subfamily B member 1 (CYP7B1)

Cytochrome P450 family 7 subfamily B member 1 (CYP7B1) is an endoplasmic reticulum-resident monooxygenase of the cytochrome P450 superfamily primarily expressed in liver, brain, and peripheral tissues. This enzyme catalyzes the 7-alpha-hydroxylation of oxysterols (e.g., 25-hydroxycholesterol, 27-hydroxycholesterol), neurosteroids (e.g., dehydroepiandrosterone, pregnenolone), and other 3-hydroxysteroids. Its function is essential in extrahepatic cholesterol catabolism, bile acid biosynthesis, neurosteroid metabolism, and regulation of cholesterol homeostasis in the brain. CYP7B1 mutations cause hereditary spastic paraplegia type 5A by disrupting normal cholesterol and neurosteroid metabolism, leading to progressive neurodegeneration and motor impairment. While it is a critical metabolic enzyme, there are currently no approved therapeutic drugs that directly target CYP7B1.

Other names

Cytochrome P450 7B1Oxysterol 7-alpha-hydroxylase24-hydroxycholesterol 7-alpha-hydroxylase25/26-hydroxycholesterol 7-alpha-hydroxylase3-hydroxysteroid 7-alpha hydroxylaseCBAS3CP7BSPG5ACytochrome P450, subfamily VIIB (oxysterol 7 alpha-hydroxylase), polypeptide 1

Not applicable due to lack of direct-acting inhibitors or activators in clinical use. The enzyme is mechanistically a NADPH-dependent monooxygenase, catalyzing 7-alpha-hydroxylation of oxysterols and steroids.