Whole Grain Consumption Increases Gastrointestinal Content of Sulfate-Conjugated Oxylipins in Pigs − A Multicompartmental Metabolomics Study

Abstract

The effects of increased intake of dietary fiber as either whole grain rye or as resistant starch compared to a typical low dietary fiber Western-style diet on the metabolomics responses were studied in gastrointestinal content and tissue, peripheral plasma, and urine using a multicompartmental nontargeted liquid chromatography-mass spectrometry (LC-MS) approach in pigs. Both unsupervised and supervised multivariate analyses were used to study differences between the intervention groups, revealing significant effects of the dietary intervention on gastrointestinal contents and urine metabolites. Consumption of a diet composed of whole grain rye flakes and enzyme treated wheat bran increased gastrointestinal content of novel sulfate- and acetic acid-conjugated oxylipins, and urinary secretion of phenolic compounds. Furthermore, potential gastrointestinal and urinary biomarkers for consumption of resistant starch, whole grain rye, and a low dietary fiber intake were detected using multiblock analysis. This study provides insight into microbial fermentation products in the gastrointestinal tract and suggests a potential role in sulfate conjugation of metabolites on the bioavailability of ingested nutrients.

Urinary Biomarkers of Whole Grain Wheat Intake Identified by Non-targeted and Targeted Metabolomics Approaches

“…Daughter ions at m/z 253, 189, 165 and 121 in MS 3 spectra (Table 2) agreed that the aglycone is enterolactone55. Therefore, metabolite 26 was recognized as enterolactone glucuronide, which is known as the mammalian fermentation product of plant lignans56.…”

Effect of Antibiotics and Diet on Enterolactone Concentration and Metabolome Studied by Targeted and Nontargeted LC–MS Metabolomics

“…Previous work from our group has found similar associations after intake of a rye-based diet fed to pigs. 39,72 Intake of LPL was associated with higher intensity in metabolites related to amino acid metabolism. Previous studies report changes in plasma amino acid composition upon intervention with rye bread compared with white wheat bread, where plasma concentrations of branched chain amino acid decreased 73 and phenylalanine and methionine increased.…”

“…Plasma (100 μL) or freeze-dried cecal (50 μg) samples were mixed with 300 μL of acetonitrile with internal standards (glycocholic acid (Glycine-1 13 C) and p -chlorophenylalanine, Sigma, MO) at a final concentration of 10 μg/mL and processed as described by Ingerslev et al…”

“…Plasma (100 μL) or freeze-dried cecal (50 μg) samples were mixed with 300 μL of acetonitrile with internal standards (glycocholic acid (Glycine-1 13 C) and p-chlorophenylalanine, Sigma, MO) at a final concentration of 10 μg/mL and processed as described by Ingerslev et al 39 Urine samples (450 μL) were mixed with 50 μL of ice-cold acetonitrile with internal standards in a final concentration of 10 μg/mL. Samples were mixed immediately and incubated for 20 min at 4 °C to precipitate proteins.…”

Effects of alpha-(1,2)-fucosyltransferase genotype variants on plasma metabolome, immune responses and gastrointestinal bacterial enumeration of pigs pre- and post-weaning

“…The analytical column was an Acquity UPLC HSS T3 (2.1 x 100 mm, 1.8 μm; Waters, Milford, MA, USA), kept at 30°C. Sample preparation and the LC-MS analysis were performed as described by Ingerslev et al [ 22 ]. In order to evaluate the performance of the analytical system, blank samples (100% acetonitrile) and pooled plasma samples from the pigs at each time point were used as quality controls and reinjected for every six samples.…”