Chemical isotope labeling liquid chromatography mass spectrometry for investigating acute dietary effects of cow milk consumption on human urine metabolome

J Food Drug Anal. 2019 Apr;27(2):565-574. doi: 10.1016/j.jfda.2018.10.007. Epub 2018 Dec 11.


Biomarker discovery has been increasingly important in the field of metabolomics for the detection and understanding of diseases. Of the many biofluids available for metabolomics, urine is a preferred option as it is non-invasive to collect and contains a wide range of metabolites reflective of the health status of the testing individual. However, urine also contains many exogenous metabolites which are introduced through various sources such as diet. This complicates the data interpretation when searching the metabolome for disease-related endogenous metabolites. Since diet is difficult to control, this work aims to study the acute effects of diet (particularly cow milk) consumption on the human urine amine/phenol submetabolome by utilizing differential chemical isotope labeling (CIL) liquid chromatography mass spectrometry (LC-MS). LC-MS analysis of 62 urine samples collected before and after (1 hour and 2 hours) milk intake resulted in the detection of 4985 metabolites with an average of 3815 ± 206 (n = 62) detected per sample. The work aims to differentiate the exogenous "food" metabolites from the endogenous metabolite pool and to determine any dietary effects from milk intake on the human urine metabolome.

Keywords: Dietary effect; Human urine metabolome; Mass spectrometry; Metabolomics; Milk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Chromatography, Liquid
  • Diet*
  • Humans
  • Isotope Labeling*
  • Mass Spectrometry
  • Milk / chemistry
  • Milk / metabolism*
  • Multivariate Analysis

Grant support

This work was supported by the Natural Sciences and Engineering Research Council of Canada, the Canada Research Chairs Program, Canada Foundation of Innovations, Genome Canada, Genome Alberta and Alberta Innovates.