The potential effects of Bisphenol A (BPA) on peripheral insulin resistance have recently gained more
attention, however, its functions on brain insulin resistance are still unknown. The aim of the present
study was to investigate the effects of BPA on insulin signaling and glucose transport in mouse brain.
The male mice were administrated of 100 lg/kg/day BPA or vehicle for 15 days then challenged with glucose
and insulin tolerance tests. The insulin levels were detected with radioimmunoassay (RIA), and the
insulin signaling pathways were investigated by Western blot. Our results revealed that BPA significantly
increased peripheral plasma insulin levels, and decreased the insulin signals including phosphorylated
insulin receptor (p-IR), phosphorylated insulin receptor substrate 1 (p-IRS1), phosphorylated protein
kinase B (p-AKT), phosphorylated glycogen synthase kinase 3b (p-GSK3b) and phosphorylated extracellular
regulated protein kinases (p-ERK1/2) in the brain, though insulin expression in both hippocampus
and profrontal cortex was increased. In parallel, BPA exposure might contribute to glucose transport
disturbance in the brain since the expression of glucose transporters were markedly decreased. In conclusion,
BPA exposure perturbs the insulin signaling and glucose transport in the brain, therefore, it might
be a risk factor for brain insulin resistance.