Prenatal ozone exposure programs a sexually dimorphic susceptibility to high‐fat diet in adolescent Long Evans rats

Abstract

Altered fetal growth, which can occur due to environmental stressors during pregnancy, may program a susceptibility to metabolic disease. Gestational exposure to the air pollutant ozone is associated with fetal growth restriction in humans and rodents. However, the impact of this early life ozone exposure on offspring metabolic risk has not yet been investigated. In this study, fetal growth restriction was induced by maternal inhalation of 0.8 ppm ozone on gestation days 5 and 6 (4 hr/day) in Long Evans rats. To uncover any metabolic inflexibility, or an impaired ability to respond to a high-fat diet (HFD), a subset of peri-adolescent male and female offspring from filtered air or ozone exposed dams were fed HFD (45% kcal from fat) for 3 days. By 6 weeks of age, male and female offspring from ozone-exposed dams were heavier than offspring from air controls. Furthermore, offspring from ozone-exposed dams had greater daily caloric consumption and reduced metabolic rate when fed HFD. In addition to energy imbalance, HFD-fed male offspring from ozone-exposed dams had dyslipidemia and increased adiposity, which was not evident in females. HFD consumption in males resulted