title: Taurocholic acid metabolism by gut microbes and colon cancer.
abstract: Colorectal cancer (CRC) is one of the most frequent causes of cancer death worldwide and is associated with adoption of a diet high in animal protein and saturated fat. Saturated fat induces increased bile secretion into the intestine. Increased bile secretion selects for populations of gut microbes capable of altering the bile acid pool, generating tumor-promoting secondary bile acids such as deoxycholic acid and lithocholic acid. Epidemiological evidence suggests CRC is associated with increased levels of DCA in serum, bile, and stool. Mechanisms by which secondary bile acids promote CRC are explored. Furthermore, in humans bile acid conjugation can vary by diet. Vegetarian diets favor glycine conjugation while diets high in animal protein favor taurine conjugation. Metabolism of taurine conjugated bile acids by gut microbes generates hydrogen sulfide, a genotoxic compound. Thus, taurocholic acid has the potential to stimulate intestinal bacteria capable of converting taurine and cholic acid to hydrogen sulfide and deoxycholic acid, a genotoxin and tumor-promoter, respectively.
authors.affiliation: a Carl R. Woese Institute for Genome Biology, University of Illinois Urbana-Champaign , Urbana , IL , USA.|b Department of Animal Sciences , University of Illinois Urbana-Champaign , Urbana , IL , USA.|c Division of Nutritional Sciences, University of Illinois Urbana-Champaign , Urbana , IL , USA.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Ridlon
authors.affiliation: a Carl R. Woese Institute for Genome Biology, University of Illinois Urbana-Champaign , Urbana , IL , USA.|b Department of Animal Sciences , University of Illinois Urbana-Champaign , Urbana , IL , USA.|c Division of Nutritional Sciences, University of Illinois Urbana-Champaign , Urbana , IL , USA.|d Department of Pathobiology , University of Illinois Urbana-Champaign , Urbana , IL , USA.
authors.forename: Patricia G
authors.initials: PG
authors.lastname: Wolf
authors.affiliation: a Carl R. Woese Institute for Genome Biology, University of Illinois Urbana-Champaign , Urbana , IL , USA.|b Department of Animal Sciences , University of Illinois Urbana-Champaign , Urbana , IL , USA.|c Division of Nutritional Sciences, University of Illinois Urbana-Champaign , Urbana , IL , USA.|d Department of Pathobiology , University of Illinois Urbana-Champaign , Urbana , IL , USA.|e University of Illinois Cancer Center, University of Illinois at Urbana-Champaign , Urbana , IL , USA.
authors.forename: H Rex
authors.initials: HR
authors.lastname: Gaskins
mesh_terms: D001646:Bile / Q000378:metabolism; D002756:Cholagogues and Choleretics / Q000378:metabolism*; D003110:Colonic Neoplasms; D003840:Deoxycholic Acid / Q000378:metabolism; D003902:Detergents / Q000378:metabolism; D000069196:Gastrointestinal Microbiome; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D006862:Hydrogen Sulfide / Q000378:metabolism; D009153:Mutagens / Q000378:metabolism; D013656:Taurocholic Acid / Q000378:metabolism*
chemical_list: D002756:Cholagogues and Choleretics; D003902:Detergents; D009153:Mutagens; D003840:Deoxycholic Acid; D013656:Taurocholic Acid; D006862:Hydrogen Sulfide
keywords: bile acid; colon cancer; deoxycholic acid; diet; hydrogen sulfide; taurine