Susceptibility of the Placenta and Fetal Brain to Maternal Probiotic Supplementation

Probiotic supplements are increasingly being touted to have health benefits for pregnant women consuming such supplements and their unborn offspring. The placenta is in direct communication with maternal blood, and bioactive agents can thus easily be transferred to this organ where they may influence gene expression by the different trophoblast (TB) cell lineages. The underlying hypothesis assessed herein is that maternal probiotic supplementation can influence the placenta and fetal brain. The composition of bacterial short-chain fatty acids (SCFAs) was examined in fecal boli of mouse dams on a maternal probiotic supplement relative to control dams. Further, SCFA and transcriptomic profiles were examined in placenta and fetal brain from conceptuses derived from dams on the probiotic supplement and conceptuses from control dams. While this treatment did not affect bacterial SCFAs, placenta and fetal brain changes were evident in male and female conceptuses carried by dams receiving probiotics relative to controls. For the placenta, females were more sensitive to maternal probiotic supplementation, whereas the opposite was the case for the fetal brain. Slc6a4 showed increased expression in female placenta from probiotic-treated dams, which could enhance uptake of maternal 5-HT. Male placenta from probiotic-treated dams had dramatic reduction in Hsd11b2 that may render them more vulnerable to maternal stress. In the fetal brain, maternal probiotic supplementation was associated with genes linked to forebrain development, suggesting this treatment might impact life-long neurobehavioral responses. Current studies suggest that maternal probiotic supplementation might lead to adverse changes in the placenta and fetal brain of their unborn children.