PROBIOTICS WATCH - Probiotics In Practice

PROBIOTICS
WATCH
ISSUE N°4 2. PHYSIOLOGICAL INTERACTION WITH THE HOST
Contents :
EDITORIAL
THE MAIN POINTS OF
THE QUARTER
1. CHARACTERISATION OF
PROBIOTICS AND
PROBIOTIC FOODS
2. PHYSIOLOGICAL
INTERACTION WITH THE
HOST
3. IN VIVO OUTCOMES OF
PROBIOTIC INTAKE
REFERENCES
KEY DATES
2.2. EFFECTS OF PROBIOTICS ON MICROBIOTA
Probiotic and nutrient intakes generate specific metabolite
procuction in mice
OBJECTIVES
The complex association of gut flora collectively extends the processing of undigested food to the benefit
of the host through metabolic capacities not encoded in mammalian genomes. At present, metabolic
insights into gut microbiota metabolism remain limited due to the inaccessibility of the intestinal habitat
and gut microbiota complexity. Over the past few decades, the practice of metabonomics has evolved
from diagnosis and identification of biomarkers for a clinical condition towards deciphering the metabolic
predisposition and responses to different individual dietary modulations. The present work monitored
faecal metabolic changes during microbial establishment collected from various groups of mice
supplemented with probiotics or nutrients.
METHODS & MEASURES
1 H-NMR-based metabolic profiling of mouse feces was carried out over time in different microbiome
mouse models, including conventional (n=9), conventionalized (n=10), and “humanized” gnotobiotic
mice inoculated with a model of human baby microbiota (HBM, n=17). HBM mice were supplemented
with Lactobacillus paracasei with (n=10) and without (n=7) prebiotics. Animals not supplemented with
prebiotics received a diet enriched in glucose and lactose as placebo.
RESULTS
In conventionalized animals, microbial populations and activities converged in terms of multivariate
mapping toward conventional mice. Both groups decreased bacterial processing of dietary proteins
when switching to a diet enriched in glucose and lactose, as described with low levels of 5-aminovalerate,
acetate, and propionate and high levels of lysine and arginine. The HBM model differs from conventional
and conventionalized microbiota in terms of type, proportion, and metabolic activity of gut bacteria (lower
short chain fatty acids (SCFAs), lactate, 5-aminovalerate, and oligosaccharides, higher bile acids and
choline). The probiotic supplementation of HBM mice was associated with a specific amino acid pattern
that can be linked to L. paracasei proteolytic activities. The combination of L. paracasei with galactosyloligosaccharide
prebiotics was related to the enhanced growth of bifidobacteria and lactobacilli, and a
specific metabolism of carbohydrates, proteins, and SCFAs.
CONCLUSION
The present study describes how the assessment of metabolic changes in feces may provide information
for studying nutrient-microbiota relationships in different microbiome mouse models.
Martin FP, Sprenger N, Montoliu I, Rezzi S, Kochhar S, Nicholson JK. Dietary modulation of gut functional ecology studied by faecal metabonomics.
J Proteome Res. 2010 Oct 1;9(10):5284-95.
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