17β-Hydroxysteroid dehydrogenases (17β-HSD, HSD17B) (EC 1.1.1.51), also 17-ketosteroid reductases (17-KSR), are a group of alcohol oxidoreductases which catalyze the reduction of 17-ketosteroids and the dehydrogenation of 17β-hydroxysteroids in steroidogenesis and steroid metabolism.
[1][2][3][4][5] This includes interconversion of DHEA and androstenediol, androstenedione and testosterone, and estrone and estradiol.
17β-HSDs have been known to catalyze the following redox reactions of sex steroids: Genes coding for 17β-HSD include: At least 7 of the 14 isoforms of 17β-HSD are involved in interconversion of 17-ketosteroids and 17β-hydroxysteroids.
Inhibitors of 17β-HSD type II are of interest for the potential treatment of osteoporosis.
[34][40] Some inhibitors of 17β-HSD type I have been identified, for example esters of cinnamic acid and various flavones (e.g.