Abstract: This research explored the effect of Nymphaea hybrid extract (NHE) on the learning and memory ability of scopolamine-induced memory impairment mice.The memory impairment model was established by intraperitoneal injection of scopolamine,and the spatial learning and memory ability of mice was determined by Morris water maze test.After the water maze experiment was completed,the mice were killed by decapitation and biochemical indicators were measured.The results showed that compared with the model group,after NHE intervention,the escape latency of the mice was significantly shortened (P<0.01),the target quadrant residence time percentage and the number of crossing platforms were increased (P<0.05 or P<0.01),the activity of SOD and GSH-PX in hippocampus and cortex of mice was significantly increased (P<0.01 or P<0.05),the content of MDA was significantly decreased (P<0.01),and the activity of AChE was significantly decreased (P<0.01),ACh content was increased (P<0.01 or P<0.05).At the same time,the results of immunoblotting showed that NHE could ameliorate the decrease of the phosphorylated ERK and CREB,as well as BDNF protein expression in hippocampus and cortex of mice induced by scopolamine.In summary,NHE could enhance the learning and memory ability of scopolamine-induced memory impairment mice.The specific mechanism involved alleviating oxidative stress damage in the brain,balancing the cholinergic system,and activating the ERK-CREB-BDNF signaling pathway.

Key words: Nymphaea hybrid extract, scopolamine, memory impairment