Maternal exposure to low-dose bisphenol A and its potential neurotoxic impact on male pups: A histological, immunohistochemical, and ultrastructural study

Background: Bisphenol A (BPA) is a widely used chemical with a harmful effect on animal and human. The neonatal and juvenile period is a highly risky neurodevelopmental period. Aim: This study aimed to determine how male albino rat pups' cerebral cortex was altered by low doses of BPA given to mothers and the role of the oxidative stress. Methods: Thirty pregnant rats were randomly split into three equal groups, negative control, and positive control: received 1 cc of corn oil once a day through gastric tube and BPA treated: a dose of 200 mu g/kg/day (dissolved in 1 cc corn oil). The male rat pups of each group were sacrificed at 1 week, 3 weeks and 6 weeks. The cerebra were then separated from the brain for histological and biochemical studies. Results: Rats administered BPA had raised levels of lipid peroxidation marker (MDA), lower levels of enzymatic antioxidants (SOD and CAT) with decreased body, cerebral weights, and decreased levels of non-enzymatic antioxidant defense (GSH). Histo-pathologically, shrunken pyramidal cells with congested blood vessels appeared. GFAP displayed increased number of positive immune-reactive astrocytes with high statistically significant increase in the area % in BPA treated group when compared to the control groups, on contrary to MBP. Semi-thin and ultra-thin BPA-sections revealed degenerative changes in myelinated axons with tiny nucleus and broken nuclear membranes. Lysosomes, dilated endoplasmic reticulum cisternae with noticeable increase in unmyelinated nerve fibers were also observed. Conclusion: The structure of the developing cerebral cortex is negatively impacted by BPA due to oxidative stress.