Host Remodeling of the Gut Microbiome and Metabolic Changes during Pregnancy

Abstract

SUMMARY Many of the immune and metabolic changes occurring during normal pregnancy also describe metabolic syndrome. Gut microbiota can cause symptoms of metabolic syndrome in non-pregnant hosts: To explore their role in pregnancy, here we characterized fecal bacteria of 91 pregnant women of varying pre-pregnancy BMIs and gestational diabetes status, and their infants. Similarities between infant-mother microbiotas increased with children’s age, and the infant microbiota was unaffected by mother health status. Gut microbiota changed dramatically from first (T1) to third (T3) trimesters, with vast expansion of diversity between mothers, an overall increase in Proteobacteria and Actinobacteria, and reduced richness. T3 stool showed strongest signs of inflammation and energy loss, however microbiome gene repertoires were constant between trimesters. When transferred to germ-free mice, T3 microbiota induced greater adiposity and insulin insensitivity compared to T1. Our findings indicate that host-microbial interactions impacting host metabolism can occur, and may be beneficial, in pregnancy.

Patterns of seasonality and group membership characterize the gut microbiota in a longitudinal study of wild Verreaux's sifakas (Propithecus verreauxi)

“…In addition, we expected microbial diversity to vary with reproductive state. In humans, within‐individual microbial diversity decreases during pregnancy (Koren et al., 2012). However, no differences were observed between lactating or pregnant females, nonreproducing females and males during the months included in the study.…”

“…Specifically, females showed lower abundances of Bacteroidetes relative to Firmicutes than males. Furthermore, women experience profound changes in the gut microbiota during pregnancy, potentially adapting the metabolism to an increased energetic demand (Koren et al., 2012). …”

Of the bugs that shape us: maternal obesity, the gut microbiome, and long-term disease risk

“…There is a significant change in gut microbiome composition from the first to the third trimester of pregnancy, accompanied by increased bacterial diversity between mothers (58). Although the composition and diversity of the gut microbiome during the first trimester is similar to that of non-pregnant healthy women, over the course of pregnancy, there is an increase in the abundance of Proteobacteria and Actinobacteria (58). Since an increase in Proteobacteria has been observed in inflammatory bowel disease, it has been suggested that a similar dysbiosis of the gut occurs during the third trimester of pregnancy (59).…”

“…Since an increase in Proteobacteria has been observed in inflammatory bowel disease, it has been suggested that a similar dysbiosis of the gut occurs during the third trimester of pregnancy (59). Pro-inflammatory cytokines (such as IL-6 and tumor necrosis factor-alpha) are notably increased in stool samples collected from women during the third trimester in comparison to the first trimester (58). Germ-free mice inoculated with third trimester microbiota show signs of increased inflammation and greater adipocity; similar results has been observed in germfree mice that are inoculated with microbiota from an obese individual (58).…”

Le microbiote intestinal à l’origine de nouvelles perspectives thérapeutiques pour les maladies métaboliques ?

“…De manière importante, il est actuellement possible de classifier les individus en fonction de la prévalence de deux à trois groupes bacté-riens, parmi lesquels les Ruminococcus, les Prévotella, et les Bacteroidetes. Ainsi, chaque individu possède son propre microbiote qui s'est progressivement mis en place depuis la première colonisation maternelle à la naissance [10], puis a subi une série de variations, notamment au cours de la transition allaitementsevrage, sous l'influence du régime alimentaire à l'âge adulte [15], lors de la grossesse [16], puis lors du vieillissement [17]. À l'image de la transmission du phénotype métabolique de prise de poids observé lors de la colonisation de souris axéniques par le microbiote d'une souris obèse [13], il est ainsi envisageable que le développement futur des maladies métaboliques puisse avoir pour origine la mise en place d'un microbiote obésogène et diabétogène au cours des premières années de la vie.…”