title: Ultra performance liquid chromatography-mass spectrometry profiling of bile acid metabolites in biofluids: application to experimental toxicology studies.
abstract: We have developed an ultra performance liquid chromatography-mass spectrometry (UPLC-MS(E)) method to measure bile acids (BAs) reproducibly and reliably in biological fluids and have applied this approach for indications of hepatic damage in experimental toxicity studies. BAs were extracted from serum using methanol, and an Acquity HSS column coupled to a Q-ToF mass spectrometer was used to separate and identify 25 individual BAs within 5 min. Employing a gradient elution of water and acetonitrile over 21 min enabled the detection of a wide range of endogenous metabolites, including the BAs. The utilization of MS(E) allowed for characteristic fragmentation information to be obtained in a single analytical run, easily distinguishing glycine and taurine BA conjugates. The proportions of these conjugates were altered markedly in an experimental toxic state induced by galactosamine exposure in rats. Principally, taurine-conjugated BAs were greatly elevated ( approximately 50-fold from control levels), and were highly correlated to liver damage severity as assessed by histopathological scoring (r = 0.83), indicating their potential as a sensitive measure of hepatic damage. The UPLC-MS approach to BA analysis offers a sensitive and reproducible tool that will be of great value in exploring both markers and mechanisms of hepatotoxicity and can readily be extended to clinical studies of liver damage.
authors.affiliation: Biomolecular Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, UK. e.want@imperial.ac.uk
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Want
authors.forename: Muireann
authors.initials: M
authors.lastname: Coen
authors.forename: Perrine
authors.initials: P
authors.lastname: Masson
authors.forename: Hector C
authors.initials: HC
authors.lastname: Keun
authors.forename: Jake T M
authors.initials: JT
authors.lastname: Pearce
authors.forename: Michael D
authors.initials: MD
authors.lastname: Reily
authors.forename: Donald G
authors.initials: DG
authors.lastname: Robertson
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Rohde
authors.forename: Elaine
authors.initials: E
authors.lastname: Holmes
authors.forename: John C
authors.initials: JC
authors.lastname: Lindon
authors.forename: Robert S
authors.initials: RS
authors.lastname: Plumb
authors.forename: Jeremy K
authors.initials: JK
authors.lastname: Nicholson
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000097:blood* / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005688:Galactosamine / Q000009:adverse effects; D005998:Glycine / Q000378:metabolism; D016014:Linear Models; D008099:Liver / Q000473:pathology*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results
chemical_list: D001647:Bile Acids and Salts; D005688:Galactosamine; D005998:Glycine