Bile Acid Profiling and Quantification in Biofluids Using Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry

Abstract

Bile acids are important end products of cholesterol metabolism. While they have been identified as key factors in lipid emulsification and absorption due to their detergent properties, bile acids have also been shown to act as signaling molecules and intermediates between the host and the gut microbiota. To further the investigation of bile acid functions in humans, an advanced platform for high throughput analysis is essential. Herein, we describe the development and application of a 15 min UPLC procedure for the separation of bile acid species from human biofluid samples requiring minimal sample preparation. High resolution time-of-flight mass spectrometry was applied for profiling applications, elucidating rich bile acid profiles in both normal and disease state plasma. In parallel, a second mode of detection was developed utilizing tandem mass spectrometry for sensitive and quantitative targeted analysis of 145 bile acid (BA) species including primary, secondary, and tertiary bile acids. The latter system was validated by testing the linearity (lower limit of quantification, LLOQ, 0.25?10 nM and upper limit of quantification, ULOQ, 2.5?5 ?M), precision (?6.5%), and accuracy (81.2?118.9%) on inter- and intraday analysis achieving good recovery of bile acids (serum/plasma 88% and urine 93%). The ultra performance liquid chromatography?mass spectrometry (UPLC-MS)/MS targeted method was successfully applied to plasma, serum, and urine samples in order to compare the bile acid pool compositional difference between preprandial and postprandial states, demonstrating the utility of such analysis on human biofluids

Fish oil, lard and soybean oil differentially shape gut microbiota of middle-aged rats

“…This could result from a higher level of cholesterol in fish oil. It is known that cholesterol is transformed into bile acids in the liver, and bile acids are excreted to the small intestine and play an important role in fat emulsification and absorption 14 . Formation of bile acids is complex and includes several reaction steps catalyzed by some enzymes 46 .…”

“…In contrast, diets rich in polyunsaturated fatty acids would enhance epithelial resistance and membrane integrity 12 . The fatty acid composition in diets has been shown to have a great impact on fat bioavailability in the small intestine under the emulsifying functions of bile acids 13, 14 . Bile acids act as signaling molecules and intermediates between the host and the gut microbiota 15 .…”

Fecal microbiota and bile acid interactions with systemic and adipose tissue metabolism in diet-induced weight loss of obese postmenopausal women

“…Bile acids were measured in the supernatant as described [36], using ACQUITY ultra performance liquid-chromatography (UPLC) (Waters Ltd., Elstree, UK) coupled to a Xevo G2 Q-ToF mass spectrometer (Waters, Manchester, UK) equipped with an electrospray ionization source operating in negative mode. TargetLynx application manager, a module of the MassLynx software, was used for the processing and quantification of the results.…”

The anti-cholesterolaemic effect of a consortium of probiotics: An acute study in C57BL/6J mice

“…Plasma samples were prepared for analysis using a previously described method 58 . Faecal pellets were lyophilised for 48 hours using a VirTis Benchtop BTP 8ZL freeze dryer (BPS FUK).…”