Long‐term exposure to high levels of decabrominated diphenyl ether inhibits CD4 T‐cell functions in C57Bl/6 mice

Abstract

In recent years, the adverse health effects of decabrominated diphenyl ether (BDE-209) have raised more concerns as a growing number of studies reported its persistence in the environment and abundance in the human population, especially in occupational environmental compartments and exposed personnel. This study applies our previous animal model simulating occupational exposure to BDE-209 to investigate its potential adverse effects on CD4 T cells. Female C57Bl/6 mice were orally gavaged with BDE-209 at a dose of 800 mg kg(-1) every 2 days for 10 months and the blood of each mouse was collected for analysis. Kinetic changes of the peripheral immune system were investigated from 1 to 5 months of exposure. The chronic effects on cytokine production, proliferation and the antigen-specific responses of CD4 T cells were evaluated at 7, 9 and 10 months, respectively. The results have shown that impaired proliferation and cytokine (IFN-γ, IL-2 or TNF-α) production of CD4 T cells were observed in BDE-209-exposed mice, accompanied by increased T regulatory cells in the blood. BDE-209 exposure in vitro also suppressed the reactivity of CD4 T cells at concentrations of 0.01, 0.1, 1 and 10 μM. Furthermore, we observed weaker antigen-specific CD4 T-cell responses to Listeria monocytogenes infection in the mice exposed to BDE-209, suggesting decreased resistance to exogenous pathogens. Taken together, these observations indicate an impaired cellular immunity after long-term and relative high-dose exposure to BDE-209 in adult mice. Copyright © 2015 John Wiley & Sons, Ltd.

Molecular Mechanisms of Polybrominated Diphenyl Ethers (BDE-47, BDE-100, and BDE-153) in Human Breast Cancer Cells and Patient-Derived Xenografts

“…Moreover, treatment with these PBDEs significantly decreased the expression of interferon-stimulated genes in cells. Likewise, reports have demonstrated that PBDEs suppress host immune defense mechanisms (Fair et al, 2012;Feng et al, 2016). Beyond these reports, the effects of PBDEs on the immune system have been largely overlooked.…”

Update of the risk assessment of polybrominated diphenyl ethers (PBDEs) in food

“…Impaired proliferation and cytokine (IFN‐γ, IL‐2 or TNF‐α) production of CD4 T cells were observed in mice exposed by gavage to 400 mg BDE‐209 /kg bw per day for 10 months, accompanied by increased T regulatory cells in the blood. Furthermore, weaker antigen‐specific CD4 T‐cell responses to L. monocytogenes infection in the exposed mice was observed, suggesting decreased resistance to exogenous pathogens (Feng, Zeng, et al., 2016 ).…”

Effect of decabrominated diphenyl ether exposure on spatial learning and memory, the expression and phosphorylation of hippocampal glutamate receptor subunits in adult Sprague-Dawley rats

“…Based on the low absorption rate of BDE 209 through gastrointestinal tract in adult rodents, which was estimated to be approximately only 0.3% of the treated dose (Feng et al, 2015), and the highest serum burden of BDE 209 in workers at an electronic waste dismantling area in Southern China, which was estimated to be 3,436 ng/g (Qu et al, 2007), we designed the exposure dose up to 1,000 mg/kg in the present study. Moreover, the same dose was applied in our previous lab work, and similar doses were also used in other previous studies that treated the adult or pregnant rats/mice with BDE 209 to investigate the thyroid endocrine toxicity, reproductive toxicity, immunotoxicity or developmental neurotoxicity (Biesemeier et al, 2011;Sarkar et al, 2016;Feng et al, 2016).…”

“…A high level of BDE 209 exposure is also estimated in some adults such as occupational personnel who engage in the manufacturing, using or recycling of products containing this chemical (Feng et al, 2016). A high concentration of environmental BDE 209 in the workplace often results in high body burden in the occupational population.…”

“…Therefore, the occupational exposure to BDE 209 is also worthy of attention and the information about the adverse effects of BDE 209 on adults is needed. To date, previous studies mostly investigated the thyroid endocrine toxicity, reproductive toxicity or immunotoxicity but rarely examined the potential neurobehavioral effects of BDE 209 on adults (Curčić et al, 2012;Sarkar et al, 2016;Feng et al, 2016).…”