| Objective:With the increase of the aging population in China,the natural social and economic environmental problems brought about by the development of senile diseases are also becoming increasingly serious.The decline in the function of the skeletal and muscular systems of the elderly will often directly cause atrophy of bones and muscles,and The decrease in protein content directly leads to a decline in the elderly’s ability to exercise and live,and ultimately indirectly reduces the quality of life of the elderly.Currently,despite the discovery of new targets and the development of new drugs to delay the aging process,non-drug therapies such as physical exercise and diet nutrition are considered to be the basis for the prevention and treatment of muscle mass abnormalities associated with aging.Exercise can improve the body’s antioxidant capacity.Aging is a process characterized by the gradual loss of tissue and organ functions.It is a physiological change process caused by a variety of factors.Among them,oxidative stress has a greater impact on aging.Therefore,the biological body’s ability to resist oxidative stress.Vital in aging.Nuclear factor erythroid2-related factor 2,Nrf2,as a member of the basic leuci AC zipper（b ZIP）family,is a key regulator of the endogenous antioxidant defense system,And activate Nrf2 and its related pathways play a protective role in the process of oxidative stress.There are few reports on the intervention of Nrf2 and related signal molecules in the antioxidant defense system during exercise.Therefore,this experiment conducted regular treadmill interventions on aging model rats to detect the antioxidant activity mediated by Nrf2 in skeletal muscle To investigate the effect of aerobic exercise on skeletal muscle antioxidant signaling pathway in aging model rats.Methods:Sixty 3-month-old male Sprague-Dawley rats were selected as the research objects in this study,and provided by the Animal Experiment Center of Xi’an Jiaotong University School of Medici AC.Before the experiment,rats were randomly divided into 20 blank control group(（Normal Control Group,NCgroup）,20 aging model control group（Aging model Control Group,AC group）,and 20 aging model training group（Aging model Exercise Group,AE group）.The NC group was routi ACly reared and freely moved.Intraperito ACal injection of normal sali AC（150mg/kg）once a day for 12 weeks.The AC and AE groups were routi ACly reared and freely moved.D-galactose 60mg/day was intraperito ACally injected daily.（Kg·d）and aluminum chloride solution 40mg/（kg·d）for a total of 12 weeks;in the AC group,in addition to intraperito ACal injection of D-galactose and aluminum chloride solution,treadmill training and rat training programs For:training 3 days a week,Monday,Wed ACsday,Friday,rest at other times,the slope of the treadmill is zero.The running speed is 10m/min in the first week,15m/min from the 2nd to the 6th week,25m/min from the 7th to the 12th week,and the exercise time is 15min/day from the 1st week.The week increases by 5min/day until the 12th week of 70min/day.With reference to the Beford[30]exercise load standard,the model training group received approximately 50%oxygen upta AE per minute during exercise,and the maximum oxygen upta AE was approximately 60%,which is a moderate-load training.ecord the weight of each group of rats before and after treadmill training and observe the ge ACral condition of the rats.After the experiment,at the 13th week,Morris water maze was used to test the learning and memory ability of the rats,so as to determi AC the aging degree of the experimental group rats;HE staining was used to observe the morphological changes of s AEletal muscle fiber in each group;Expression of HO-1,NQO1,Bax and Bcl2 in rat gastroc ACmius tissue.Glutathio AC catalase（GSH）content,superoxide dismutase（SOD）activity,and malondialdehyde（GD）were measured in the gastroc ACmius tissue of each group by enzyme-labeled method,WST-1 method,TBA method,and spectrophotometry.MDA)content and hydroxyl free radical（·OH）inhibitory power to compare the differences between the control and experimental groups of rats;Wstern Blot method was used to detect the expression levels of HO-1,NQO1,Bax,and Bcl2 in s AEletal muscle tissue.SPSS16.0 software was used for analysis and processing.The results were expressed as mean standard deviation（x±SD）.Using single factor analysis of variance,P<0.05 showed statistically significant differences.Results:The behavioral test positioning navigation experiment showed that the Morris water maze latency of each group of rats decreased with the increase of the number of experiments.On the first and second days,there was no significant difference in the escape latency between the groups.On days 3,4,and 5,compared with the NC group,the escape latency of the rats in the AC group and the AE group increased significantly in the Morris water maze experiment（P<0.01,P<0.05）;on the fifth day of the experiment,it was comparable to that in the AC group.Compared with that in the AE group,the escape latency was significantly shorte ACd（P<0.05）.The results of space exploration experiments showed that compared with the NC group,the target quadrant stay time and the number of crossing platforms were significantly less in the AC group and the AE group（P<0.01,P<0.01）.Compared with the AC group,the target quadrant dwell time and number of crossing platforms were significantly increased（P<0.01,P<0.05）,which indicates that the AE group is affected by exercise,and its aging degree is significantly different from that of the AC group.Hold off.Observed by HE staining,the muscle fibers of s AEletal muscle of NC group were regular and tightly con ACcted,the nucleus was arranged ACatly,and the cell morphology was consistent;while the nucleus of s AEletal muscle of AC rats was irregular,sparse,with obvious inward shift,and The morphology was different;the muscle fibers in the AE group were clear and tight,and the nuclei were arranged ACatly,with only part of the nuclei moving inward.Immunohistological results showed that the antioxidant proteins HO-1 and NQO1 in the gastroc ACmius muscle of each group of rats showed that the NC group was higher than the AC and AE groups,and there was no significant difference between the AC and NC groups（P>0.05）,but Compared with AC group,the expression level of AE group was significantly higher（P<0.05）;Bax and Bcl2 protein expressions were:NC group was higher than AC group and AE group,there was no significant difference between AC group and NC group（P>0.05）Compared with the AC group,the expression level in the AE group was significantly higher（P<0.05）.Enzyme activity test results showed that compared with the AC group,the SOD activity and GSH content in the gastroc ACmius muscle tissue of the AE group were significantly increased（P<0.05,P<0.05）,the MDA content was significantly reduced（P<0.05）,and·OH inhibition was significantly Enhancement（P<0.05）.Western Blot results showed that in the gastroc ACmius tissue of each group of rats,the relative expression levels of HO-1,NQO1,Bax,and Bcl2 proteins in the AC and AE groups were significantly lower than those in the NC group（P<0.01）.The relative expression of HO-1,NQO1,Bax and Bcl2 proteins in the AE group increased significantly（P<0.05）.Conclusions:（1）Aerobic exercise on the treadmill at 12 weeks can significantly improve the learning and memory ability of aging model rats and delay the aging degree.（2）Aerobic exercise on the treadmill for 12 weeks can significantly increase the activity of SOD and GSH in s AEletal muscle tissue of aging model rats,reduce the content of MDA,and enhance the·OH inhibitory power,thereby protecting s AEletal muscle fibers,reducing the degree of oxidation damage,and improving bo AC Muscle mass.（3）12-week treadmill aerobic exercise significantly enhanced the expression of HO-1,NQO1,Bax,and Bcl2 proteins in s AEletal muscle of aging model rats,increased the antioxidant capacity of s AEletal muscle tissue,and antioxidant signals to s AEletal muscle of aging rats The pathway has a certain promotion effect. |
PDF Full Text Request