Effects of bisphenol S, a major substitute of bisphenol A, on neurobehavioral responses and cerebral monocarboxylate transporters expression in mice.

Bisphenol A has been restricted in a large variety of products. Bisphenol S (BPS) is its major substitute. Yet, the impacts of BPS on the central nervous system are unknown, especially in vulnerable populations like children. The aim of this study was to investigate the effects of BPS on behavioral performances and the expression of cerebral monocarboxylate transporters (MCTs). Male Swiss mice were exposed to BPS at 100 μg/kg in drinking water for 10 weeks. The protocol started after the lactation period, which is a sensitive period of early social-emotional development. Elevated T-maze and open field tests were used to measure respectively, anxiety-related and activity-related behaviors. Molecular expressions of MCTs isoforms (MCT1, MCT2, MCT4) were determined in the frontal cortex. Data showed that BPS does not affect mRNA expression of MCTs. However, BPS decreases the number of entries into the open arms and the time spent on them for BPS-treated mice. These data reveal an anxiogenic effect of BPS. For locomotor activity and exploratory behavior levels, differences did not reach a statistically significant level in the BPS-exposed group. The effect of BPS on behavioral performances unravels a putative risk for psychopathology development in early childhood and calls for more attention.