Effects Of Treadmill Training On Learning And Memory Ability And Hippocampal Neuron Apoptosis In Naturally Aged Mice

Objective: To study the effect of exercise on learning and memory ability of aging mice by making 12-month-old natural aging mice model and applying8-week treadmill training intervention,and to explore the mechanism of delaying brain aging through hippocampal neuron apoptosis.Methods: 24 male C57 mice were divided into 3-month-old young group(Y group)and 12-month-old group.The old group was further divided into natural aging group(SC group)and old treadmill group(SE group).In SE group,45 min / D and 5d / W treadmill training was adopted,including 5 m / s in 0-5 min,8 m / s in 5-10 min,12 m / s in 10-40 min and 5 m / s in 40-45 min.treadmill training lasted for 8 weeks.24 hours after the end of the last training,Morris water maze test was used to observe the spatial learning and memory ability of the experimental mice;after the end of the behavioral experiment,the mice were killed,bilateral hippocampus was quickly stripped on the ice bag,liquid nitrogen was put into quick freezing,and the m RNA expression levels of Bax,Bcl-2 and Caspase3 in hippocampus were detected by real-time fluorescent quantitative PCR(RT q PCR).Results:(1)Morris water maze test showed that: in the spatial navigation training,the average escape latency of Se group was shorter than that of SC group on the 2nd,3rd and 5th day(P < 0.05);the average escape latency of Y group was significantly lower than that of SC group on the 2nd and 4th day(P < 0.05).Intra group comparison: there was no significant difference in escape latency between days1-5 in SE group(P > 0.05);there was significant difference in escape latency between days 1 and 2,days 2 and 3,and days 4 and 5 in Y group(P < 0.05);there was significant difference in average latency between days 3 and 4 in SC group(P < 0.05).In the space exploration experiment,the number of platform crossing in SE group increased significantly compared with that in SC group(P < 0.01),but there was no significant difference between SC group and Y group(P > 0.05).(2)RT q PCR results showed that: compared with SC group,the expression levels of Pro apoptotic factor Bax and Caspase3 m RNA in hippocampus of Se group were significantly decreased(P < 0.05),and the expression levels of anti apoptotic factor bcl-2 m RNA were significantly increased(P < 0.05).Compared with Y group,the m RNA expression levels of Pro apoptotic factors Bax and Caspase3 in hippocampus of SC group were significantly increased(P < 0.05),and the m RNA expression levels of anti apoptotic factor Bcl-2 were significantly decreased(P < 0.05).Conclusion: exercise can antagonize the apoptosis of hippocampal neurons by regulating the gene expression of Bcl-2,Bax and caspase 3,thus protecting the aging neurons and improving the decline of learning and memory function related to aging.