Vitamin D3 protects intrauterine growth restriction induced by cooking oil fume derived fine particulate matters

Background: Cooking oil fume (COF) is an important source of indoor air pollution which severely affects human health, and sufficient vitamin D3 (VitD3) is necessary for maternal and child health. However, the effects of cooking oil fume-derived PM2.5 (COF-PM2.5) on birth outcomes and whether VitD3 could protect from adverse effects caused by COFs-PM2.5 are still unclear. Methods: Twenty-four pregnant rats were divided into 4 groups and treated with various treatments: normal feeding, COFs-PM2.5 intratracheal instillation, VitD3 intragastric administration, and COFs-PM2.5 and VitD3 co-treatment, respectively. The fetal rats were obtained in pregnant 21 days and the development of them was recorded. Morphological changes in umbilical cord were measured with HE staining, and the oxidative stress and inflammatory levels were also investigated. Western blotting and RT-PCR was used to detect the expression of angiogenesis related factors. Results: We successfully established an intrauterine growth restriction model in rats induced by COFs-PM2.5 where fetus weight significantly decreased after COFs-PM2.5 exposure. As for the umbilical cord vasculature, the wall thickened and the lumen narrowed down, and the contractility of the umbilical cord vasculature enhanced after COFs-PM2.5 exposure. COFs-PM2.5 exposure also increased the oxidative stress and inflammation level and activated the HIF-1α/eNOS/NO and VEGF/VEGFR2/eNOS signaling pathway. Interestingly, VitD3 intervention significantly increased the fetus weight and attenuated the injury of umbilical cord vascular, and partly or completely reversed the changes in the ROS/eNOS/ET-1 axis caused by COF-PM2.5. Conclusions: The findings of this study suggested that COF-PM2.5 exposure could contribute to intrauterine growth restriction through disturbing the ROS/eNOS/ET-1 axis, while VitD3 supplementation could be an effective prophylactic measurement.