Abstract
The present study investigated the reproductive and developmental toxicity of male offspring induced by prenatal ZEN exposure and explored the possible mechanism. 64 pregnant rats were allocated into four groups and fed with ZEN contaminated (0, 5, 10 and 20 mg/kg) diet during the whole gestation period. The results showed that, F1 male foetal viability was not affected while newborn bodyweight (BW) was significantly decreased after prenatal exposure to ZEN. Decreased BW was found on postnatal day (PND) 21 but not on PND 63 in ZEN exposed male rats. Moreover, adult testis weight increased with seminiferous tubules atrophy as well as decreased spermatocytes and mature sperms (35% and 31%) in ZEN-treated rats. Meanwhile, circulating levels of luteinizing hormone and testosterone decreased while estradiol increased in ZEN-treated rats. These impairments concurred with down-regulations of 3β-HSD and StAR in both mRNA and protein levels in weaned and adult testis. Furthermore, gene and protein expressions of GnRHr and Esr1 were inhibited in the ZEN-treated foetal brain. These results suggested that prenatal ZEN exposure disrupted the system regulating the reproductive hormones and testis development through hormone related genes, which may result in a reproductive dysfunction in adult male offspring.