The influence of maternal malnutrition on folate and inositol production and transport in the placenta and gut - a mechanism for fetal growth restriction and fetal disorders?
Maternal malnutrition and micronutrient deficiencies can alter fetal development. However, the mechanisms underlying these relationships are poorly understood. We used a systems-physiology approach to investigate diet-induced effects on maternal gut microbes and folate/inositol transport in the maternal/fetal gut and placenta. Female mice were fed a control diet (CON) diet, undernourished (UN, restricted by 30% of CON intake) or a high fat diet (HF, 60% kcals fat) during pregnancy to model normal pregnancy, fetal growth restriction, or maternal metabolic dysfunction, respectively. At gestational day 18.5 we assessed circulating folate levels by microbiological assay, relative abundance of gut lactobacilli by G3PhyloChipTM, and folate/inositol transporters in placenta and maternal/fetal gut by qPCR/immunohistochemistry. UN and HF-fed mothers had lower plasma folate concentrations vs. CON. Relative abundance of three lactobacilli taxa were higher in HF vs. UN and CON. HF-fed mothers had higher gut proton coupled folate transporter (Pcft) and reduced folate carrier 1 (Rfc1), and lower sodium myo-inositol co-transporter 2 (Smit2), mRNA expression vs. UN and CON. HF placentae had increased folate receptor beta (Frβ) expression vs. UN. mRNA expression of Pcft, folate receptor alpha (Frα) and Smit2 was higher in gut of HF fetuses vs. UN and CON. Transporter protein expression was not different between groups. Maternal malnutrition alters abundance of select gut microbes and folate/inositol transporters, which may influence maternal micronutrient status and delivery to the fetus, impacting pregnancy/fetal outcomes.Competing Interest StatementThe authors have declared no competing interest.View Full Text