Moderate treadmill exercise improves spatial learning and memory deficits possibly via changing PDE-5, IL-1 β and pCREB expression

Alzheimer's is a progressive disorder of the nervous system. Prior studies suggested that physical activity contributes to the improvement of cognitive impairment and slows down pathogenesis of AD; however, the exact mechanisms for this have not been fully understood. Therefore, in this study, we examined the effect of aerobic training before and after induction of Alzheimer's on spatial learning and memory, expression of interleukin-1 beta (IL-1 beta), cAMP-responsive element-binding protein (pCREB), and Phosphodiesterase-5 (PDE-5) in the hippocampus of male rats Wistar. A beta was microinjected into the CA1 area of the hippocampus animals. The moderate treadmill exercise protocols for pre and post induction of Alzheimer's were the same (5 days/week, for 4 weeks with a customized regime). The Morris Water Maze (MWM) method has been to assess spatial learning and memory. The real time-PCR method was used to measure gene expression. Our results showed that intrahippocampal injection of A beta 1-42 impaired spatial learning and memory which was accompanied by reduced pCREB activity and elevated IL-1 beta and PDE-5 in the hippocampus of rats. In contrast, moderate treadmill exercise ameliorated the A beta 1-42-induced spatial learning and memory deficit, which was accompanied by restored pCREB activity and decreasing IL-1 beta and PDE-5 levels. In conclusion, our finding suggests that exercise before and after Alzheimer's induction leads to an increase in pCREB and an alleviation of inflammation which likely involved in ameliorating spatial learning and memory deficits in an animal model of AD.