Ultra Performance Liquid Chromatography-Mass Spectrometry Profiling of Bile Acid Metabolites in Biofluids: Application to Experimental Toxicology Studies

摘要

We have developed an ultra performance liquid chromato-ngraphy-mass spectrometry (UPLC-MSE) method to mea-nsure bile acids (BAs) reproducibly and reliably innbiological fluids and have applied this approach fornindications of hepatic damage in experimental toxicitynstudies. BAs were extracted from serum using metha-nnol, and an Acquity HSS column coupled to a Q-ToFnmass spectrometer was used to separate and identifyn25 individual BAs within 5 min. Employing a gradientnelution of water and acetonitrile over 21 min enablednthe detection of a wide range of endogenous metabo-nlites, including the BAs. The utilization of MSE allowednfor characteristic fragmentation information to benobtained in a single analytical run, easily distinguishingnglycine and taurine BA conjugates. The proportions ofnthese conjugates were altered markedly in an experi-nmental toxic state induced by galactosamine exposurenin rats. Principally, taurine-conjugated BAs were greatlynelevated (∼50-fold from control levels), and werenhighly correlated to liver damage severity as assessednby histopathological scoring (r 0.83), indicating theirnpotential as a sensitive measure of hepatic damage. ThenUPLC-MS approach to BA analysis offers a sensitivenand reproducible tool that will be of great value innexploring both markers and mechanisms of hepato-ntoxicity and can readily be extended to clinical studiesnof liver damage.