Effects Of Aerobic Exercise On Brain Aging, Learning And Memory Ability And Cerebellar BDNF Expression In Rats

Objective: to make aging model of male SD rats by intraperitoneal injection of D-galactose in rats before modeling,after modeling process,aerobic exercise(swimming,60min/d)intervention index of aging rats brain detection,spatial learning and memory ability of cerebellar brain-derived neurotrophic factor BDNF expression the study of aerobic exercise on brain aging rats on learning and memory ability and cerebellar BDNF.Methods:SD rats(72 rats,March age,male)according to SD(before modeling exercise preconditioning group(ND),model group(NNa),the control group were injected with saline(NDs),the motion in the modeling process(NDS group),exercise group after modeling)and NDN(after modeling natural feeding group)were randomly divided into 6 groups.In the model after the end of each group were randomly divided into 2 groups: M group(SDM group,NDM group,NNa M group,NDs M group,NDSM group,NDNM group,M group,Morris)for 7 days of experimental behavior;N group(SDN group,NDN group,NNa N group,NDs N group,NDSN group NDNN group,N group),7 days of natural feed;a total of 12 groups(n=6).After grouping of SD rats aging model(Dgalactose,100mg/kg/d);the rats in different periods of aerobic exercise,the ability of using Morris water maze test to detect the spatial learning and memory;free radicals were detected in the rat brain after the related index(superoxide dismutase SOD GSH-PX,GSH Px,MDA content;MDA)using real-time PCR,Western-blot,BDNF expression was detected in rat cerebellar in experimental technique.Resu Lts:(1)the SD rats in NNa group were in good condition,quick action,normal diet,white hair,and the ND group had obvious natural aging characteristics: yellow hair,slow action,poor appetite,lethargy.(2)free radical test results: the content of MDA and the activity of SOD and GSH-Px in SDN group were not significantly different from those in NDN group(P>0.05).the content of MDA in group NDs N was significantly lower than that in group NDN(P<0.05),SOD(P<0.05),GSH-Px(P<0.05).The activity of was significantly higher than that of group NDN;the content of MDA in group NDSN was significantly lower than that in group NDNN(P<0.05),the activity of SOD and GSH-Px was significantly higher than that of group NDNN(P<0.05).(3)water maze navigation experiment results: the average escape latency of the rats withthe increase of the number of training will be gradually reduced and stabilized,the average escape latency between the different groups have different groups in time;the average escape latency of second days less than first days(P<0.05),the average escape latency of each group(except NDSM group)was less than that of second days(P<0.05),in group NNa M,the mean escape latency of NDs M group was stable from third days(P>0.05).However,the average escape latency of SDM group,NDM group,NDSM group and NDNM group were gradually stabilized at the beginning of fourth days(P>0.05),after the navigation experiment for first days,the average escape time of NNa M group was less than that of NDM group(P<0.05),the mean escape time of NDSM group and NDNM group increased slowly(P<0.05),in the navigation experiment of the sixth day,there was no significant difference between the SDM group and the NDM group in the mean escape time(P>0.05),compared with the NDNM group,the rats in the NDSM group had significantly lower mean escape time(P<0.05),The experiment of space(second quadrant water entry)showed that there was no significant difference between the SDM group and the NDM group(P>0.05).The number of NDs M group crossing the original platform was significantly higher than that of group NDM(P<0.05).The number of NNa M group crossing the original platform was significantly higher than that of group NDM(P<0.05),The number of NDSM group crossing the original platform was significantly higher than that of group NDNM(P<0.05).(4)the results of BDNF real-time PCR and Western-blot NNa N group BDNF m RNA cerebellar brain(P<0.05)expression and protein(P<0.05)was significantly higher than that of NDN group,BDNF m RNA in cerebellum of SDN group had no significant difference compared with NDN group(P>0.05).No significant differences in expression of SDN BDNF protein group cerebellar compared with NDN group,no significant(P>0.05);NDs N group m RNA(P<0.05)of cerebellar BDNF expression and protein(P<0.05)was significantly higher than that of NDN group.the expression of BDNF m RNA in cerebellum of NDSN group was significantly higher than that of group NDNN(P<0.05)the expression of protein quality was significantly higher than that of NDNN group(P<0.05)M group and its corresponding N group had the same trend,and there was no significant difference between the groups(P>0.05).Conclusion:(1)the morphological characteristics of SD rats after modeling and the related indexes of free radicals proved that the model was successful.(2)SD rats were intervened by aerobic exercise before modeling.The expression of BDNF in cerebellum of rats was not increased,and the spatial learning and memory ability of rats did not change significantly.(3)in the process of modeling and after modeling,SD rats were subjected to aerobic exercise intervention,which could increase the expression of BDNF in the cerebellum of rats and increase the spatial learning and memory ability of rats.(4)the experimental results show that aerobic exercise can increase the expression of cerebellar BDNF in rats,which may be one of the mechanisms that retard the decline of spatial learning and memory ability in rats.