5α-Androstan-3β-ol is a steroidal androgen.¹It binds to the androgen receptor in a cell-free assay (IC₅₀= 1.7 µM) and activates the pregnane X receptor (PXR) in HepG2 cells in a reporter assay (EC₅₀= 0.8 µM).^1,25α-Androstan-3β-ol also inhibits the androst-4-ene-3,17-dione hydroxylase activities of 16α- and 6β-hydroxylase but not 16β- or 7α-hydroxylase (IC₅₀s = 70, 110, >150, and >150 µM, respectively).³It decreases testis weight and sperm production in mice when administered at a dose of 30 mg/kg.⁴

1.Fang, H., Tong, W., Branham, W.S., et al.Study of 202 natural, synthetic, and environmental chemicals for binding to the androgen receptorChem. Res. Toxicol.16(10)1338-1358(2003) 2.Ekins, S., Chang, C., Mari, S., et al.Human pregnane X receptor antagonists and agonists define molecular requirements for different binding sitesMol. Pharmacol.72(3)592-603(2007) 3.Murray, M., and Mehta, I.Structure-activity relationships in the in vitro modulation of rat hepatic microsomal androst-4-ene-3,17-dione hydroxylase activities by derivatives of 5α- and 5β-androstaneJ. Steroid Biochem.35(3-4)465-471(1990) 4.Martinot, E., Baptissart, M., VÉga, A., et al.Bile acid homeostasis controls CAR signaling pathways in mouse testis through FXRalphaSci. Rep.742182(2017)