Serologic biomarkers for inflammatory bowel disease (IBD)
have
yielded variable differentiating ability. Quantitative analysis of
a large number of metabolites is a promising method to detect IBD
biomarkers. Human subjects with active Crohn’s disease (CD)
and active ulcerative colitis (UC) were identified, and serum, plasma,
and urine specimens were obtained. We characterized 44 serum, 37 plasma,
and 71 urine metabolites by use of 1H NMR spectroscopy
and “targeted analysis” to differentiate between diseased
and non-diseased individuals, as well as between the CD and UC cohorts.
We used multiblock principal component analysis and hierarchical OPLS-DA
for comparing several blocks derived from the same “objects”
(e.g., subject) to examine differences in metabolites. In serum and
plasma of IBD patients, methanol, mannose, formate, 3-methyl-2-oxovalerate,
and amino acids such as isoleucine were the metabolites most prominently
increased, whereas in urine, maximal increases were observed for mannitol,
allantoin, xylose, and carnitine. Both serum and plasma of UC and
CD patients showed significant decreases in urea and citrate, whereas
in urine, decreases were observed, among others, for betaine and hippurate.
Quantitative metabolomic profiling of serum, plasma, and urine discriminates
between healthy and IBD subjects. However, our results show that the
metabolic differences between the CD and UC cohorts are less pronounced.