Protective effects of Ziziphus jujuba fruit extract against ethanol-induced hippocampal oxidative stress and spatial memory impairment in rats

The current study assessed the effects of Ziziphus jujuba fruit extract on hippocampal oxidative stress and spatial memory of rats exposed to ethanol. Male Wistar rats were randomly divided into control, Z. jujuba treated (200 mg/kg, p.o.), ethanol (4 g/kg, p.o.) and Z. jujuba plus ethanol groups. The animals were treated daily by oral gavage for 8 weeks. The learning and memory performance was assessed using Morris water maze (from day 55 to 60). At the end of experiment, rats were sacrificed by decapitation and brains were dissected out for thiobarbituric acid reactive substances, and the activities of antioxidative enzymes (glutathione peroxidase and superoxide dismutase) determinations in the hippocampus. It was found that combined Z. jujuba extract-ethanol treatment significantly decreased TBARS level and increased glutathione peroxidase activity compared to the ethanol group (p<0.05), whereas no significant difference was observed in superoxide dismutase activity. In Morris water maze, rats treated with Z. jujuba prior to ethanol significantly shortened total path length during the acquisition period and enhanced the spent time in the correct quadrant on probe trial performance compared to ethanol treated rats (p<0.05). The results show that Z. jujuba fruit extract improved spatial memory impairment induced by ethanol, due in part, by its antioxidant activities.