Coupled Enzymatic Treatment and Mass Spectrometric Analysis for Identification of Glucuronidated Metabolites in Human Samples

Abstract

Glucuronidation is the most common phase II modification and plays an important role in human clearance metabolism. Glucuronidated metabolites have also been linked to disease development and microbiota–host co‐metabolism. Although many of these compounds have been identified, the total number of unknown glucuronides and their impact on the human host's physiology can only be estimated. Herein, we describe the combination of an untargeted metabolomics analysis and enzymatic metabolic conversion for the selective detection of glucuronide conjugates by using UPLC‐MS/MS in human urine samples. Our study demonstrates that this powerful strategy can be used for the selective identification of glucuronidated molecules and to discover unknown natural metabolites. In total, we identified 191 metabolites in a single sample including microbiota‐derived compounds as well as previously unidentified molecules.

Systematic, Modifying Group-Assisted Strategy Expanding Coverage of Metabolite Annotation in Liquid Chromatography–Mass Spectrometry-Based Nontargeted Metabolomics Studies

“…Modifications such as acetylation, glucuronidation, sulfation, and glycine conjugation occur frequently not only on large molecules , but also on small molecular metabolites. − Modifications can change structures and bioactivities of metabolites, which are very often directly linked to consequences of pathophysiological processes . It has been reported that alterations of modified metabolites are associated with the progression of many human diseases, such as prostate cancer, breast cancer, liver cancer, and end-stage renal disease .…”

Investigation of the individual human sulfatome in plasma and urine samples reveals an age-dependency

“…4,5 The main research interest of phase II modications has been for the metabolism of drugs, nutritional components, toxins, and doping agents. [6][7][8][9][10] Phase II modications have recently also been linked to the cometabolism of the gut microbiome with their human host. Mainly sulfation but also glucuronidation are important modications for metabolites derived from the co-metabolism of the microbiome and its host.…”

Sensitive mass spectrometric analysis of carbonyl metabolites in human urine and fecal samples using chemoselective modification

“…22 The development of chemical biology tools in this newly developed research field is limited in comparison with other well-established 'omics' fields. [23][24][25][26][27] These tools are required to allow for selective and advanced metabolite analysis. Chemoselective modification strategies for targeted carbonyl metabolite analysis represent an effective approach to facilitate detection and identification of a metabolite class of interest.…”