Sex-dependent physiological consequences of perinatal bisphenol A exposure in seasonal Djungarian hamsters

Bisphenol A (BPA) has been identified as a substance of very high concern regarding its effects on the reproductive and metabolic health of human and wildlife. However, the impacts of early-life BPA exposure on the mammalian reproductive and metabolic adaptations to seasonal changes have never been addressed. We investigated the effects of perinatal BPA exposure on the fertility and maternal behaviour of the seasonal Djungarian hamster, as well as growth, puberty onset, and the ability of male and female offspring to adapt to seasonal changes later in life. Female Djungarian hamsters maintained under a long photoperiod (16 h light/8 h dark) were orally exposed to 5 µg/kg of body weight/day of BPA, or vehicle, during breeding, gestation, and lactation. BPA-treated female hamsters had a higher number of living offspring despite providing less maternal care, as compared to untreated females. Male and female offspring exposed perinatally to BPA exhibited an enhanced growth after weaning, along with reduced (in females) or normal (in males) food intake, but no modification in pubertal onset. When adult, females exposed perinatally to BPA exhibited a reduction of ovarian atretic follicles, whereas perinatally BPA-exposed males showed unaffected morphometric testicular parameters. Further, BPA-exposed females displayed a deficit in energy expenditure when compared to unexposed females. When transferred to a short photoperiod, BPA-exposed females, but not males, exhibited an accelerated integration of the short photoperiod phenotype, with faster reproductive quiescence and a larger decrease in body weight, food intake, and glycemia. Overall, this study reveals that perinatal BPA exposure in Djungarian hamsters alters maternal behaviour, offspring postnatal survival growth, and energy expenditure, and later in life reproductive and metabolic adaptations to seasonal change, with major sex differences.