Hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 7 (HSD3B7)

Hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 7 (HSD3B7) is an endoplasmic reticulum membrane-associated enzyme that catalyzes an essential step in the biosynthesis of bile acids from cholesterol. It specifically catalyzes the oxidation and isomerization of 7α-hydroxycholesterol to 7α-hydroxy-4-cholesten-3-one, initiating the conversion of cholesterol into bile acids. These bile acids are crucial for dietary fat and fat-soluble vitamin absorption and for the regulation of cholesterol and lipid metabolism in the liver and intestines. Deficiency or dysfunction of HSD3B7 can cause congenital bile acid synthesis defect type 1, leading to neonatal cholestasis, progressive liver disease, and malabsorption syndromes. HSD3B7 is part of the short-chain dehydrogenase/reductase superfamily and is not directly targeted by current pharmacological agents, although bile acid replacement therapy may be used to bypass its deficiency.

Other names

3 beta-hydroxysteroid dehydrogenase type 73-beta-HSD VIIC(27) 3-beta-HSDSDR11E33 beta-hydroxy-delta 5-C27-steroid oxidoreductaseCholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenaseShort chain dehydrogenase/reductase family 11E, member 3CBAS1PFIC4

Drugs (such as exogenous bile acids) used in the context of HSD3B7 deficiency act as replacement therapy to correct metabolic deficiencies resulting from the lack of functional endogenous bile acids.