Concomitant increased brain-derived neurotrophic factor and interleukin-6 protein expression with postnatal exercise-associated spatial memory preservation in prenatal-stressed rat offspring

Any perturbation to the neurohormonal-immune system during the fetal developmental period carries over effects later in life. Prenatal stress (PS) induces hippocampal changes in the structure and functions that could lead to cognitive impairment and psychiatric disorders. Increasing evidence indicates that physical exercise could ameliorate cognitive impairment in both young and old rats. We investigated the therapeutic effect of the postnatal voluntary wheel running (VWR) exercise on cognitive impairment that developed from prenatal maternal restraint stress. The restraint stress was carried out during gestation day (GD)14–21 in the pregnant Sprague-Dawley rats. VWR was performed in the rat pups on postnatal day (P)25–40. After that, spatial memory performance was tested with the Morris water maze (MWM) during P36–40. The effect of prenatal stress and the potential effects of the VWR on the levels of hippocampal synaptic proteins, brain-derived neurotrophic factor (BDNF), and interleukin (IL)-6 in the rat offspring were ascertained with Western blot analysis. Stress during the prenatal period induced decreases in synaptic proteins and BDNF, but an increase in IL-6. Postnatal exercise ameliorated the adverse effects of PS on protein expression. The MWM test confirmed the ameliorative effect of VWR on spatial memory performance of the pups. Our findings suggest that postnatal exercise has a high potential to ameliorate the adverse effects of maternal stress and return healthy neuroendocrine-immune system and spatial memory to rat offspring.