Maternal Vitamin D3 Supplementation in an Oxidized-Oil Diet Protects Fetus from Developmental Impairment and Ameliorates Oxidative Stress in Mouse Placenta and Fetus

Background: Fried food has increased in popularity worldwide. However, deep frying can increase the production of peroxidative toxins in food, which might be harmful to fetal development. The antioxidative effect of vitamin D3 (VD3) has been reported previously. Objectives: This study aimed to explore how maternal VD3 supplementation in an oxidized-oil diet during gestation affects fetal anti- oxidative ability and development. Methods: Pregnant mice were randomly assigned into 3 groups: Control group (diet with fresh soybean oil), OSO group [diet with oxidized soybean oil (OSO)], and OSOV group (diet with OSO and 10,000 IU/Kg VD3). Mice were fed with the corresponding diet during gestation. On day 16.5 of gestation, the placenta and fetus were harvested to analyze antioxidative status. Results: Maternal oxidized-oil diet during gestation significantly fi cantly reduced placental vessel abundance, labyrinth zone area, and fetal body weight. However, dietary VD3 supplementation prevented these negative effects of oxidized-oil diet. Maternal intake of oxidized-oil diet increased serum concentrations of malondialdehyde, total-nitric oxide synthase, and inducible nitric oxide synthase, whereas VD3 supplementation showed a protection effect on it. Additionally, maternal VD3 supplementation increased the levels of antioxidative enzymes and the nuclear translocation of nuclear factor erythroid 2-related factor 2 (NRF2), thereby protecting placenta and fetus from apoptosis and oxidative stress caused by an oxidized-oil diet. The gene expression and protein levels of a fatty acid transporter solute carrier family 27 member 1 in the fetal liver were increased by maternal VD3 supplementation under oxidized-oil diet. Notably, NRF2 could be coimmunoprecipitated with the VD receptor in the placenta. Conclusions: Maternal VD3 supplementation could protect fetus from oxidized-oil diet induced developmental impairment by alleviating oxidative stress in the placenta and fetus through the VD receptor/NRF2 pathway, at least partially. Thus, ensuring adequate levels of VD3 through supplementation is often critical during pregnancy.