Longitudinal changes in offspring body weight, fat mass and sex hormone levels according to maternal bisphenol A exposure during gestation and lactation

摘要

We investigated the intergenerational effect of exposure to bisphenol A (BPA) during gestation and lactation on adipose storage and sexual maturation using sex hormone measurements and an improved statistical approach. Pregnant Sprague-Dawley rats were gavaged with BPA at 50 u.g/kg body weight (B W)/ day or 50 mg/kg BW/day, or an equivalent volume of sesame oil (controls) from day 7 of gestation until pup weaning. We examined the pubertal development daily from postnatal day (PND) 25. Pups were euthanized on PND 15, 30, 45, or 60. At that time, truncal blood was collected and three adipose deposits were dissected and weighed. From the collected blood, we measured the levels of four sex hormones. Body weights of the remaining animals were recorded until 37 weeks of age. Male, but not female, pups born to BPA-exposed rats had significantly increased body weights. In addition, prenatal BPA exposure showed an inverted U-shaped relationship with body weight change in male pups; this effect was long lasting. Prenatal exposure to a relatively low dose of BPA influenced the timing of puberty onset, which was earlier than in the control group. Moreover, sex hormones, body fat-pad weights and body weights changed over time according to ex-posure level. Our results showed that prenatal BPA exposure influences intergenerational development of early puberty onset and adipose storage, which lasts into adulthood, as shown by statistical approaches and an improved study design that compensatedfor weaknesses in previous investigations.