Gestational 1-nitropyrene exposure causes gender-specific impairments on postnatal growth and neurobehavioral development in mice.

ABSTRACT

1-Nitropyrene (1-NP), a typical nitrated polycyclic aromatic hydrocarbon, is widely distributed in the environment and is well known for its mutagenic effects. Recently, we found that gestational 1-NP exposure induced fetal growth restriction. In this study, we further evaluated the effect of in utero 1-NP exposure on postnatal growth and neurobehavioral development in the offspring. Pregnant mice were administered with 1-NP (10 µg/kg) by gavage daily in late pregnancy (GD13-GD17). The body weight of each offspring was measured from PND1 to 12 weeks postpartum. Exploration and anxiety related activities were detected by open-field test at 6 weeks postpartum. Learning and memory were assessed by Morris Water Maze at 7 weeks postpartum. And depressive-like behaviors were estimated by sucrose preference test at 10 weeks postpartum. Significant body weight reduction was observed in 1-NP-exposed female offspring at PND1, PND14 and PND21 while the lower body weight was only found at PND1 for 1-NP-exposed male offspring. Exploration and anxiety activities at puberty, and depressive-like behavior in adulthood were not disturbed in offspring prenatally exposed to 1-NP. Interestingly, spatial learning and memory ability at puberty was impaired in females but not in males prenatally exposed to 1-NP. These findings suggest that gestational 1-NP exposure delays postnatal growth and impaired neurobehavioral development in a gender-dependent manner.