Developmental Outcomes of Prenatal E-cig Aerosol Vaping

Abstract

Electronic cigarettes (e-cigs) are tobacco products that have become popular among youth and young adults due to targeted advertising and misconceptions about their safety. The unfounded perception that e-cigs are less harmful than traditional cigarettes may result in the use of e-cigs during pregnancy. There are limited studies evaluating the effects of e-cig aerosol exposure on pregnancy in animal models and only a single report of gestational e-cig exposure in humans. To examine the impact of prenatal e-cig aerosol exposure on pregnancy and development we utilized a pregnant Sprague-Dawley rat model combined with a chronic, whole-body, environmental exposure to e-cig aerosols generated by commercially available e-cig atomizers. We found that exposure to e-cig aerosols containing nicotine significantly reduced fetal and neonatal growth, but aerosols without nicotine did not. Growth restriction was accompanied by reduced blood flow in the maternal uterine artery and fetal umbilical artery. Analysis of signature amino acid profile revealed altered concentrations in maternal and fetal plasma of animals exposed to e-cig aerosols with nicotine. Amino acid concentrations in the fetal lungs were altered by e-cig aerosols regardless of nicotine. RNA sequencing of fetal lung transcriptome showed altered expression after exposure to e-cig aerosols with and without nicotine. E-cig aerosols containing nicotine altered neonatal lung morphology and produced trends in respiratory mechanics that may increase the workload of breathing. Interestingly, e-cig aerosols with and without nicotine reduced the area of the pressure-volume loop during forced oscillation techniques which may indicate increased atelectasis in neonatal lungs. The effects of prenatal e-cig aerosol exposure were more pronounced in animals exposed to aerosols containing nicotine, however, e-cig aerosols without nicotine were also found to effect the physiology of pregnancy. Further studies will be required to identify molecular mechanisms of e-cig aerosol induced alterations to pregnancy and development. The data presented in these studies lay a foundation for our understanding of prenatal exposure to e-cig aerosols by providing evidence that e-cig vaping during pregnancy can have deleterious outcomes for the developing offspring.