Date Published: July 10, 2019
Publisher: Public Library of Science
Author(s): Karen Elizabeth Nava-Castro, Helena Solleiro-Villavicencio, Víctor Hugo del Río-Araiza, Mariana Segovia-Mendoza, Armando Pérez-Torres, Jorge Morales-Montor, Shanaz Hashmi Dairkee.
Bisphenol A (BPA) is an endocrine disruptor compound with estrogenic activity, possessing affinity for both nuclear (ERα and ERβ) and membrane estrogen receptors. The main source of BPA exposure comes from the contamination of food and water by plastic storage containers or disposable bottles, among others, in which case BPA is easily ingested. Exposure to BPA during early pregnancy leads to lifelong effects; however, its effect on the immune system has not been fully studied. Since endocrine and immune systems interact in a bidirectional manner, the disruption of the former may cause permanent alterations of the latter, thus affecting a future anti-parasitic response. In this study, neonate BALB/c mice were exposed to a single dose of BPA (250 μg/kg); once sexual maturity was reached, they were orally infected with Trichinella spiralis (T. spiralis). The analyses performed after 5 days of infection revealed a decreased parasitic load in the duodenum of mice in the BPA-treated group. Flow cytometry analyses also revealed changes in the immune cell subpopulations of the infected animals when compared to the BPA-treated group. RT-PCR analyses of duodenum samples showed an increased expression of TNF-α, IFN-γ, IL-4, IL-5, and IL-9 in the BPA-treated group. These findings show a new aspect whereby early-life exposure to BPA contributes to the protection against T. spiralis by modulating the anti-parasitic immune response.
Endocrine disrupting compounds (EDC’s) are highly lipophilic exogenous substances that bind to hormone receptors. They are capable of interfering in the biosynthesis, storage, metabolism and function of various hormones in the exposed organisms as well as in their offspring . BPA is an estrogenic EDC that binds to different estrogen receptors located in both the nucleus (ERα and ERβ) and the membrane of the cell [2, 3]. This compound is mostly used in the plastic industry with an approximate production of 5×109 kg per year , and it is the main component in the manufacture of plastic containers and epoxy resins. Therefore, humans are exposed to BPA on a daily basis, with the average diet (food and beverages contaminated by their plastic containers) being the most important source of risk.
The aim of the present study was to evaluate the effects of a single neonatal administration of BPA in mice and its effects on the establishment of the gastrointestinal parasite T. spiralis and the corresponding duodenal immune response.
The present results provide further proof that early exposure to BPA affects cytokine expression and antibody production, turning into a Th1 response during the adult life and resulting in a decreased susceptibility to intestinal parasitic infection with T. spiralis. These effects emphasize the high sensitivity of the immature immune system to BPA during the neonatal period, altering its effector mechanisms in adult life. Due to its ability to modulate the cytokine expression profile and the constitution of several immune cell populations, the administration of BPA during critical periods of development could serve as a preventive tool against infections with T. spiralis in the adult stage.