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Exposure to endocrine disruptors in utero appears to alter epigenetics in the male germ-line and subsequently promote adult-onset disease in subsequent generations. Fetal exposure to bisphenol A (BPA), a highly prevalent endocrine disruptor in environment, has been shown to alter epigenetic modification and result in glucose intolerance in adulthood. However, whether fetal exposure to BPA can induce epigenetic modification and phenotypic changes in their subsequent offspring are still unclear. The present study was designed to investigate whether exposure to BPA in early life induced glucose intolerance in the offspring through male germ line, and the underlying epigenetic molecular basis. F0 pregnant SD rats were received corn oil or 40 μg/kg/day of BPA during gestation and lactation. F1 male rats were maintained to generate F2 offspring by mating with untreated female rats. Both the F1 rats after weaning and the F2 offspring were not received any other treatments. Our results showed that male F2 offspring in the BPA group exhibited glucose intolerance and β-cell dysfunction. Decreased expression of Igf2 and associated hypermethylation of Igf2 were observed in islets of male F2 offspring. In addition, similar effects were observed in female F2 animals, but the effects were more pronounced in males. Moreover, abnormal expression and methylation of Igf2 was observed in sperm of adult F1 male rats, indicating that epigenetic modification in germ cells can be partly progressed to the next generation. Overall, our study suggests that BPA exposure during early life can result in generational transmission of glucose intolerance and β-cell dysfunction in the offspring through male germ line, which is associated with hypermethylation of Igf2 in islets. The changes of epigenetics in germ cells may contribute to this generational transmission., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

BPA, a common environmental endocrine disruptor, has been reported to induce epigenetic changes and disrupt glucose homeostasis in F1 offspring through maternal exposure. However, no studies have examined whether maternal BPA exposure can exert multigenerational effects of glucose metabolic disorder on F2 generation through the altered epigenetic information. The aim of the current study was to investigate whether BPA exposure can disrupt glucose homeostasis in F2 offspring and the underlying epigenetic mechanism. In the present study, F0 pregnant dams were orally administered at a daily dose of 40μg/kg body weight during gestation and lactation. The F1 and F2 generations were obtained and not exposed to BPA anymore. The glucose and insulin tolerance tests were carried out to evaluate the glucose homeostasis level. The relative hormone level and the relative gene expression were also examined. F2 generation was found to exhibited glucose intolerance and insulin resistance in ipGTT and ipITT, as well as the downregulation of glucokinase (Gck) gene in liver. DNA methylation pattern of Gck promoter in the F2 generation of hepatic tissue and F1 generation of sperm was then performed. The Gck promoter in F2 hepatic tissue became completely methylated in the all CpG sites compared with five unmethylated sites in controls. In the F1 sperm, the global DNA methylation was decreased. However, there is only CpG site -314 was differently methylated between BPA and controls in sperm. In conclusion, F0 maternal BPA exposure during gestation and lactation can induce impaired glucose homeostasis in the F2 offspring through the transmission of sperm. The underlying epigenetic modifications in the sperm of F1 generation remain to be further elucidated., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Exposure to bisphenol A (BPA), a monomer widely used to manufacture polycarbonate plastics, has been reported to be associated with abnormalities of liver function and hepatic damage. However, the molecular mechanism under the pathogenesis of hepatic injury is unclear. In this study, the effect of perinatal exposure to BPA at the reference dose of 50 µg/kg/day on the apoptotic index in the liver of rat offspring was investigated. Increased levels of ALT and enhanced cell apoptosis were observed in the liver of rat offspring at 15 and 21 weeks, and significantly increased activity of caspase-3 and caspase-9 and elevated levels of cytochrome c were also confirmed. In addition, significant change in the expression levels of Bcl-2 and Bax were found in BPA-treated offspring at 21 weeks. For in vitro experiments, liver mitochondria were isolated from neonatal rats and were treated with BPA. BPA treatment led to a significant increase in mitochondrial permeability transition. Moreover, the supernatant from BPA-treated mitochondria significantly increased apoptotic changes in nuclei isolated from liver tissue. In conclusion, the study demonstrates that BPA induces mitochondria-mediated apoptosis in hepatic cells, which may contribute to long-term hepatotoxicity induced by early-life exposure to BPA.

Perfluorooctane sulfonate (PFOS) is a widespread environmental contaminant that is detected in the lung of mammals. The mechanisms underlying PFOS-induced lung cytotoxicity remain unclear. The main purpose of this study was to evaluate the cytotoxic effects of PFOS on human lung cancer A549 cells and its possible molecular mechanism. A549 cells were treated with PFOS (0, 25, 50, 100 and 200 μm) and the cellular apoptosis, mitochondrial membrane potential as well as intracellular reactive oxygen species were determined. In this study, PFOS induced a dose-dependent increase in A549 cell toxicity via an apoptosis pathway as characterized by increased percentage of sub-G1, activation of caspase-3 and -9, and increased ratio of Bax/bcl-2 mRNA expression. In addition, there was obvious oxidative stress, represented by decreased glutathione level, increased malondialdehyde level and superoxide dismutase activity. N-Acetylcysteine, as an antioxidant that is a direct reactive oxygen species scavenger, can effectively block PFOS-induced reactive oxygen species generation, mitochondrial membrane potential loss and cell apoptosis. These data indicate that PFOS induces apoptosis in A549 cells through a reactive oxygen species-mediated mitochondrial dysfunction pathway mechanism., (Copyright © 2012 John Wiley & Sons, Ltd.)