Hyocholic acid

Hyocholic acid

Names
IUPAC name 3α,6α,7α-Trihydroxy-5β-cholan-24-oic acid
Systematic IUPAC name (4R)-4-[(1R,3aS,3bS,4S,5R,5aR,7R,9aR,9bS,11aR)-4,5,7-Trihydroxy-9a,11a-dimethylhexadecahydro-1H-cyclopenta[a]phenanthren-1-yl]pentanoic acid
Other names γ-Muricholic acid; Iocholic acid
Identifiers
CAS Number	547-75-1
3D model (JSmol)	Interactive image
ChEBI	CHEBI:81244
ChEMBL	ChEMBL1908063
ChemSpider	83777
ECHA InfoCard	100.008.124
EC Number	208-935-8
KEGG	C17649
PubChem CID	92805
UNII	2H5H0Q47FL
CompTox Dashboard (EPA)	DTXSID20862167
InChI InChI=1S/C24H40O5/c1-13(4-7-19(26)27)15-5-6-16-20-17(9-11-23(15,16)2)24(3)10-8-14(25)12-18(24)21(28)22(20)29/h13-18,20-22,25,28-29H,4-12H2,1-3H3,(H,26,27)/t13-,14-,15-,16+,17+,18+,20+,21-,22+,23-,24-/m1/s1 Key: DKPMWHFRUGMUKF-KWXDGCAGSA-N
SMILES C[C@H](CCC(=O)O)[C@H]1CC[C@@H]2[C@@]1(CC[C@H]3[C@H]2[C@@H]([C@@H]([C@H]4[C@@]3(CC[C@H](C4)O)C)O)O)C
Properties
Chemical formula	C24H40O5
Molar mass	408.579 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Hyocholic acid or 3α,6α,7α-trihydroxy-5β-cholan-24-oic acid is a bile acid found as one of the main forms in pig,^[1] and at low concentrations in other species including humans.^[2][3] Hyocholic acid differs from the primary bile acids found in humans by having a third hydroxyl group in the α-conformation at the 6-position, unlike cholic acid, which has a 12-hydroxyl, and chenodeoxycholic acid which has neither a 6- or 12-hydroxyl. It also differs from the muricholic acids found in rodents, as they are 6β-hydroxylated, and can have the 7-hydroxyl in either the α- or β- positions, forming α- or β-muricholic acids.

Hyocholic acid is conjugated in the liver before secretion with taurine or with glycine to give taurohyocholate or glycohyocholates. Bacterial 7α-dehydroxylation in the colon produces the secondary bile acid, hyodeoxycholic acid. Epimerization of the 7-hydroxyl to the β-position is found in ω-muricholic acid (also known as β-hyocholic acid).^[4]

The enzyme responsible for the 6-hydroxylation reaction of chenodeoxycholic acid in the pig is the cytochrome P450 CYP4A21.^[5]

Hyocholic acid can be found in humans with cholestasis^[6] and may be increased after sleeve gastrectomy for obesity.^[7]