Prebiotic supplementation during pregnancy alters the gut microbiota

Prebiotic supplementation during pregnancy alters gut microbiota and fetomaternal immunology

During pregnancy, the maternal diet modifies the intestinal microbiota. Diet can thus impact the immune system of the foetus in utero by modifying the transfer of immune factors, microbial factors and bacterial metabolites mediated by the umbilical cord, placenta and amniotic fluid. Prebiotics are fibers that act as fermentable substrates for specific bacteria, which either leads to the release of metabolites, or exerts direct effects on immune cells. We hypothesized that prebiotic supplementation during pregnancy could shift the maternal microbiota towards higher production of metabolites and promote a healthy immune system in the foetus.

We demonstrated in mice that prebiotic (galacto-oligosaccharides/inulin) supplementation during gestation modifies the gut microbiota with an increase in the abundance of Bacteroidetes and a decrease in Firmicutes associated with an increase in metabolite production.
Of these metabolites, the concentration of acetate is increased in the faeces as well as in the amniotic fluid. Prebiotic supplementation also increases the frequency of immunoregulatory B and T lymphocyte cells in gestational tissues (uterus and placenta) and in the foetus (in the marrow and intestine). These cells are then found in the pups at 6 weeks of life.
We thus demonstrated that prebiotic supplementation during pregnancy leads to the transmission of specific microbial and immune factors from the mother to the offspring, allowing the establishment of a tolerogenic immune response in the foetus, which could protect the offspring from future conditions such as food allergies.

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Modification date: 11 September 2023 | Publication date: 26 December 2022 | By: MW