Maternal microbes mediate diet-derived damage

New research in The Journal of Physiology has found, using a mouse model, that microbes in the maternal intestine may contribute to impairment of the gut barrier during pregnancy.   

Scientists previously thought the changes in maternal metabolism that happen during pregnancy were due entirely to pregnancy hormones. We now believe that changes in the microbes that live in the maternal gut may contribute to these metabolic changes. If they do, then this provides us with a therapeutic opportunity to modify this microbial community during pregnancy to improve maternal and offspring health. 

The gut acts as a barrier preventing microbes and other intestinal contents from entering the bloodstream, but in pregnant mice more molecules were able to cross this barrier. This loss of barrier was even greater when pregnant mice were fed a high-fat diet, resulting in increased inflammatory markers in maternal circulation. 

These changes in the mother may be impacting the development of the placenta, as placental oxygen levels were decreased by maternal high-fat diet. Changes in the placenta could contribute to altered fetal development which was what the authors found in the fetal intestines. Impaired fetal intestinal development could lead to altered intestinal function after birth and ultimately impact the baby’s metabolism. 

Researchers discovered these changes by feeding their female mice a diet high in fat for 6 weeks before and throughout pregnancy. They then studied how the intestinal community of microbes changed. They tested the maternal intestinal barrier by measuring how much of a large molecule was able to cross the from the maternal intestine into the bloodstream and then looked at how the placenta and fetus developed.

Deborah Sloboda, senior author on the study, said:

“We are currently investigating when these changes in maternal barrier function occur and how they interact with the microbes in the intestines to influence the metabolism of the mom and development of the baby.” 

Notes for Editors

  1. High-fat diet modulates maternal intestinal adaptations to pregnancy, induces placental hypoxia, alters fetal gut barrier proteins and immune markers https://physoc.onlinelibrary.wiley.com/doi/10.1113/JP277353 (link will only work after the embargo date. Before then, please email the press office for a copy of the paper)
  2. The Journal of Physiology publishes advances in physiology which increase our understanding of how our bodies function in health and disease. http://jp.physoc.org
  3. The Physiological Society brings together over 4,000 scientists from over 60 countries. The Society promotes physiology with the public and parliament alike. It supports physiologists by organising world-class conferences and offering grants for research and also publishes the latest developments in the field in its three leading scientific journals, The Journal of Physiology, Experimental Physiology and Physiological Reports. www.physoc.org 

Contacts:

The Physiological Society: 

Julia Turan, Communications Manager

pressoffice@physoc.org

+44(0)20 7269 5728

Corresponding author:

Deborah M Sloboda

McMaster University

+1(905) 525-9140 x 22250

sloboda@mcmaster.ca