[Study on bisphenol A induced primary cultured mesencephalic neuronal cell injury by oxidative stress].

OBJECTIVE: To investigate the effect and mechanism of bisphenol A, a common EDCs, on the primary cultured mesencephalic neuronal cell injury. METHODS: mesencephalic neuronal cells were obtained from embryonic 14-15 day SD fetuses and were cultured in serum free medium for 4 or 7 days in vitro, 1,10,25,50 and 100 micromol/L bisphenol A were added to the medium and intracellular ROS, SOD, MDA, GSH were measured after 24 or 48hours, respectively. Flow cytometry was used to detect the neuronal cell apoptosis. Tyrosine hydroxylase immunohistochemistry was used to identity and count the ratio of dopaminergic neuronal cell. RESULTS: The intracellular ROS was dose dependently increased by bisphenol A in all treated groups, and it appeared to be a nonselective effect when the concentration of bisphenol A were higher than 50 micromol/L, and concomitantly decreased SOD, GSH and increased MDA. The apoptotic neuronal cells were significantly increased at 501 micromol/L and 100 micromol/L. The ratio of Tyrosine hydroxylase positive neuronal cell was dose dependently decreased with the concentration of bisphenol A. CONCLUSION: ROS induced by bisphenol A may play a major role in its cytotoxicity on dopaminergic neuronal cell.

[Adverse effects of nonylphenol on the reproductive development of F1 male SD rats in sexual maturation period].

OBJECTIVE: To investigate the adverse effects of perinatal exposure to nonylphenol (NP) on the reproductive development of F1 male SD rats in sexual maturation period. METHODS: The pregnant rats were randomly divided into control, 50 mg/kg, 100 mg/kg, and 200 mg/kg NP groups respectively. NP was administered to dams by gavage from gestation day 7 to weaning period. Rat pups were sacrificed at postnatal day 55. The concentration of serum testosterone was measured by radioimmunoassay. The epididymis was subjected to the determination of sperm count and motility while the testis was submitted to histopathological and immunohistochemical analyses. RESULTS: Compared with control, the concentration of serum testosterone, sperm count and motility in the 200 mg/kg NP dose groups significantly decreased (P < 0.05), and the histopathological examination revealed that NP-treated groups had higher rates of maldeveloped siminiferous tubules, smaller amount of Sertoli cells and weaker spermatogenesis. The expression of proliferative cell nuclear antigen (PCNA) significantly decreased in the 200 mg/kg NP dose groups (P < 0.05). The expression of Arom in 100 mg/kg and 200 mg/kg NP dose groups was lower than that in control. There was no significant difference in ER expression between the control and NP-treated groups. CONCLUSION: These findings indicated that 200 mg/kg Nonylphenol apparently damaged the reproductive development of F1 male SD rats in the sexual maturation period.