The impact of moderate-intensity swimming exercise on learning and memory in aged rats: The role of Sirtuin-۱

Objective(s): The purpose of this study was to evaluate the effect of moderate-intensity swimming exercise on learning and memory by the Morris water maze test. Changes in the expressions of cyclic AMP-response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) proteins alternative pathway which were activated by sirtuin-۱ (SIRT-۱) were investigated. Materials and Methods: The study included thirty-two male Sprague-Dawley rats (۳۵۰-۵۰۰ g, ۱۱-۱۲ and ۱۵–۱۶ months old). The rats were randomly divided into four groups with ۸ rats in each group. The groups were designed as follows:  Control-۱ (۱۱-۱۲ months), Exercise-۱ (۱۱-۱۲ months), Control-۲ (۱۵-۱۶ months), Exercise-۲ (۱۵-۱۶ months). Moderate-intensity exercise was assigned for ۳۰ min/day, ۵ days/week, for the whole training period of ۸ weeks. Results: There were statistically significant differences between the groups on the third day (P=۰.۰۰۵) when swim speeds increased in the exercise groups. There was a statistically significant difference between Exercise ۱ and Exercise ۲ groups, the entries in the platform zone decreased in Exercise ۲ group (P=۰.۰۲۶). While there were no histopathological findings observed in any group, increased  SIRT-۱, BNDF, and CREB  expressions were seen in exercise groups compared with control groups.Conclusion: In aged rats exercising at moderate intensity, increased expression of CREB and BDNF, and SIRT-۱ could improve hippocampal-dependent memory.

Keywords:

BDNF , CREB , Learning-memory , Sirtuin-۱ , Swimming exercise