Effects Of Aerobic Exercise Intervention On Brain Aging, Learning And Memory Ability And Cerebellum GAP-43 Gene Expression In Rats

Objective: In this study, aerobic exercise intervention in aging rats at different times, and to explore the impact of aerobic exercise intervention on rat brain aging, the ability of learning and memory and cerebellum of GAP-43 gene effects in different aging period.Methods: 3-month-old adult male SPF grade Sprague Dawley(SD) rats 180, weighing 400 ±20g. After adaptive feeding for 3 days, randomly divided into six groups: normal saline control group(Na), acute aging group(N1), Aerobic exercise intervention group before aging(S1),Aerobic exercise intervention group during the aging process(S2), aging naturally feeding group(N2) and Aerobic exercise intervention group after aging(S3).After aging modeling, large set of random each further divided into two groups, a group for 7 days Morris water maze test, the M group( NaM, N1 M, S1 M group, S2 M, N2 M, S3M), and the other group for 7 days naturally feeding, the N group( NaN, N1 N, S1 N, S2 N, N2 N,S3N), 12 groups and n = 15.Then decapitated drawn. Detect SOD, GSH-Px activity and SOD content in rats' cerebral cortex, the Real time PCR detect the expression of GAP- 43 mRNA in rats' cerebellum, the Western Bolting detect the expression of GAP- 43 protein in rats' cerebellum. Results:(1) Radical detection results: The SOD, GSH-Px activity of Na were significantly higher than N1(P<0.01),and the MDA of Na were significantly lower than N1(P<0.01); There were no significantly difference of S1 SOD, GSH-Px activity, the content of MDA between S1 and N1(P> 0.05); The SOD, GSH-Px activity of S2 were significantly higher than N1(P<0.01),and the MDA of Na were significantly lower than N1( P<0.01); There were no significantly difference of SOD, GSH-Px activity, the content of MDA between S3 and N2(P> 0.05);(2)Morris water maze test results: The positioning navigation results show that the stable spatial learning and memory of NaM,S2 M were formed after the first three days of training, but N1 M,S1M, S3 Mand N2M after fourth days of training; The first quadrant into the water space exploration results show that the number of crossing platform of NaM was significantly higher than N1 M and N2M(P<0.01); There were no significantly difference between the number of crossing platform of S1 M and N1M(P> 0.05); The number of crossing platform of S2 M was significantly higher than N1M(P<0.01); There were no significantly difference between the number of crossing platform of S3 M and N2M(P> 0.05);(3) The expression of GAP-43 in rats' cerebellum: there is no significant difference between the expression of GAP-43 mRNA and protein of S1 and N1 in rats' cerebellum(P >0.05); The expression of GAP-43 mRNA of S3 were significantly higher than N2 in rats' cerebellum(P<0.01),but there were no significantly difference between the expression of GAP-43 protein of S3 and N2(P> 0.05).(4) Correlation analysis results: The expression of GAP-43 mRNA and protein in rats' cerebellum and the number of crossing platform showed a positive correlation(P<0.05); Conclusion:(1) The agingmodel was successfully established by D- galactose injection in 6 weeks.(2) Aerobic exercise intervention could not improve the learning and memory ability of the rats before the aging model, and improve the ability of learning and memory in rats was not obvious.(3) Aerobic exercise intervention could improve the expression of GAP-43 mRNA and protein in the rats' cerebellum during aging model, and improve the ability of learning and memory in rat.( 4)Aerobic exercise intervention could not improve the expression of GAP-43 mRNA and protein in the rats' cerebellum after aging model,and improve the ability of learning and memory in rats was not obvious.(5) The expression of GAP-43 GAP-43 mRNA and protein were positive correlation with learning and memory ability, and it may be one of the mechanisms of aerobic exercise intervention in learning and memory.