Hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 2 (HSD3B2)

Hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 2 (HSD3B2) is an enzyme essential for the biosynthesis of all classes of steroid hormones, including glucocorticoids, mineralocorticoids, androgens, and estrogens. It catalyzes the oxidative conversion of Δ5-3β-hydroxysteroids (e.g., pregnenolone, DHEA) to Δ4-3-keto steroids (e.g., progesterone, androstenedione), the key step in steroidogenesis. HSD3B2 is primarily expressed in steroidogenic tissues (adrenal gland, testes, ovaries), and mutations cause congenital adrenal hyperplasia (CAH) with a spectrum of phenotypes from mild to severe salt-wasting, ambiguous genitalia, and abnormal sexual maturation. Pharmacological inhibition of HSD3B2 disrupts steroid hormone production and is the basis for drugs used to treat hormone-related conditions.

Other names

3 beta-hydroxysteroid dehydrogenase/Delta 5→4-isomerase type II3-beta-hydroxy-Delta(5)-steroid dehydrogenaseSteroid Delta-isomeraseHSD3B2HSDB3B3-beta-HSD IISDR11E23-beta-HSD adrenal and gonadal type3-beta-hydroxy-5-ene steroid dehydrogenaseProgesterone reductaseDelta-5-3-ketosteroid isomeraseShort chain dehydrogenase/reductase family 11E, member 2

Inhibition of enzymatic activity: The above drugs block the conversion of Δ5-3β-hydroxysteroids to Δ4-3-keto steroids, thereby reducing the synthesis of progesterone, corticosteroids, or adrenal androgens.