Cytochrome P450 family 11 subfamily B member 1 (CYP11B1) (CYP11B1)

Human 11β-hydroxylase, encoded by the CYP11B1 gene, is a mitochondrial cytochrome P450 enzyme primarily expressed in the adrenal cortex. It plays a critical role in the final steps of glucocorticoid biosynthesis by catalyzing the conversion of 11-deoxycortisol to cortisol and 11-deoxycorticosterone to corticosterone [1, 7]. Dysregulation or genetic deficiency of this enzyme leads to significant endocrine disorders, such as Cushing's syndrome (excess cortisol) or congenital adrenal hyperplasia (CAH) due to 11β-hydroxylase deficiency [2, 6]. In CAH, the block in cortisol production leads to an accumulation of precursors like 11-deoxycorticosterone, which causes hypertension and hypokalemia, and shunts steroids toward androgen production, causing virilization [6, 12]. Pharmacological inhibition of CYP11B1 is a key therapeutic strategy for managing endogenous Cushing's syndrome, with drugs like osilodrostat and metyrapone effectively lowering cortisol levels [2, 4]. However, therapeutic use requires careful monitoring to avoid adrenal insufficiency and manage potential side effects related to precursor buildup [2, 6].

Other names

Steroid 11β-hydroxylaseSteroid 11β-monooxygenaseCytochrome P450 11B1, mitochondrialCytochrome P450C11P450C11CPN1CYP11BFHICytochrome P450, subfamily XIB, polypeptide 1

Competitive inhibition of the CYP11B1 enzyme, which blocks the final step of cortisol synthesis by preventing the conversion of 11-deoxycortisol to cortisol and 11-deoxycorticosterone to corticosterone.