Neuroprotective effect of resveratrol against scopolamine-induced cognitive impairment and oxidative stress in rats

Abstract

The objective of this study was to examine the neuroprotective effect of resveratrol on cognitive impairment induced by scopolamine, a muscarinic antagonist, in rats. Memory impairment was induced by administration of sco- polamine (1 mg/kg) intraperitoneally. Cognitive functions were assessed using radial arm maze, an active avoidance paradigm. Oxidative stress parameters like malondialdehyde, catalase and superoxide dismutase were assessed and acetylcholinesterase activity was estimated. More working and reference memory errors in the radial arm maze test and fewer avoidances in the active avoidance test were observed with scopolamine in the 1 mg/kg i.p.-treated animals. This phenomenon is a clear indication of memory impairment. Oral administration of resveratrol (20 mg/kg) inhibited the occurrence of higher working, reference memory errors and prevented the incidence of less avoidances. Resveratrol appeared to have exerted memory-enhancing effects by inhibiting acetylcholinesterase activity and prevented the rise in malondialdehyde levels and loss of antioxidant enzymes catalase and superoxide dismutase, showing antioxidant po- tential. Based on the above results of behavioral and biochemical studies, it can be concluded that resveratrol protected against scopolamine-induced loss of cognition. The results also indicate that resveratrol is an antioxidant and an acetyl- cholinesterase inhibitor, and it is likely that resveratrol's protective effect is related to its antioxidant and cholinesterase inhibitory effects.