Urinary metabolites of 2-bromoethanamine identified by stable isotope labelling: evidence for carbamoylation and glutathione conjugation.

TitleUrinary metabolites of 2-bromoethanamine identified by stable isotope labelling: evidence for carbamoylation and glutathione conjugation.
Publication TypeJournal Article
Year of Publication2011
AuthorsShipkova P, Vassallo JD, Aranibar N, Hnatyshyn S, Zhang H, Clayton AT, Cantor GH, Sanders M, Coen M, Lindon JC, Holmes E, Nicholson JK, Lehman-McKeeman L
JournalXenobiotica
Volume41
Issue2
Pagination144-54
Date Published2011 Feb
ISSN1366-5928
KeywordsAmino Acids, Animals, Carbamates, Ethylamines, Glutathione, Isotope Labeling, Kidney, Male, Rats, Rats, Sprague-Dawley, Time Factors
Abstract

2-Bromoethanamine (BEA) causes renal papillary necrosis (RPN) in rats after a single dose and has been widely used as a model compound for studying the lesion. Although the metabolism of BEA may be an important determinant of toxicity, the metabolic fate of the compound has not been fully elucidated. To date, the only identified BEA metabolites are aziridine, 2-oxazolidone and 5-hydroxy-2-oxazolidone. In this study, stable isotope labelling (SIL) of BEA analogs ((¹³C and ²H) were used to differentiate generated BEA metabolites from endogenous molecules which enabled the accurate liquid chromatography mass spectrometry detection of more than 180 novel metabolites. BEA metabolism was evaluated in rats after acute administration of a non-toxic dose (50 mg/kg) and a toxic dose (250 mg/kg) that caused frank RPN and polyuria. Newly identified metabolites include three carbamoylation products, two mercapturic acids and a group of amino acid conjugates. Overall, the results indicate that BEA metabolism is very complex, suggest the potential formation of reactive intermediates and establish that BEA is subject to conjugation with glutathione. The results also demonstrate the utility and sensitivity of the SIL approach for identification of metabolites from small, reactive compounds.

DOI10.3109/00498254.2010.529179
Alternate JournalXenobiotica
PubMed ID21043805