Objective: 

The chronic effects of the antioxidant polyphenol resveratrol on cognitive performance in old rats have been analyzed.

Methods: 

To evaluate the possible improvements in memory processes, two different tests have been used, the spatial working memory in the 8-arm radial maze, and the novel object recognition as a form of non-spatial working memory test. Old (24 months) Wistar male rats (500–550g) were treated with resveratrol (20 mg/kg) or vehicle (corn oil, 1 ml/kg) for 28 days, intraperitoneally. Trials on radial maze were judged complete when rats had chosen all 8 baited arms or spent 20 min in the trial. Re-entered or non entered arms were computed as errors.

Results: 

A significant improvement in memory processes was observed after chronic treatment with resveratrol in old animals. Chronic vehicle treatment did not change task performance respect to the test made just before the treatment. However, chronic resveratrol treatment improved task performance in the radial test with respect to controls, and with respect to the test made just before the treatment with a 33% reduction in trial time, 41% errors reduction (90% errors reduction due to none entered into some arms and 29% errors reduction due to re-entered arms). Moreover, the time spent exploring the novel object compared to familiar object increased 1.6 times in the group of rats treated with resveratrol, while control rats spent the same time at the beginning and end of treatment.

Conclusions: 

Resveratrol enhanced working memory. The results suggest the usefulness of resveratrol treatment to recover from the age associated behavioural deficits observed in cognitive capacities.