【摘要】 目的:探讨D-半乳糖致衰老的SD大鼠在衰老前和衰老过程中进行有氧运动对其脑衰老和额叶NCAM表达的影响。方法:3月龄雄性SD大鼠60只随机分成运动预处理组(SD组)、衰老组(ND组)、生理盐水对照组(NNa组)、衰老过程中有氧运动干预组(NDs组),n=15。取材后,测定大脑皮质的SOD、GSH-Px活性和MDA含量,Real-time PCR、Western blotting检测额叶NCAM基因的表达,免疫组织化学检测其表达部位。结果:ND组大鼠较NNa组出现了嗜睡、食欲不振、行动迟缓、毛色枯黄卷曲并大量脱落等衰老体征;ND组SOD、GSH-Px活性非常显著性低于NNa组(P<0.01),MDA含量非常显著性多于NNa组(P<0.01),SD组SOD、GSH-Px活性和MDA含量较ND组均无显著性差异(P>0.05),NDs组SOD、GSH-Px活性非常显著性高于ND组(P<0.01),MDA含量非常显著性少于ND组(P<0.01);ND组额叶NCAM基因的mRNA和蛋白质表达水平非常显著性低于NNa组(P<0.01),SD组额叶NCAM基因的mRNA和蛋白质表达水平较ND组无显著性差异(P>0.05),NDs组额叶NCAM基因的mRNA和蛋白质表达水平非常显著性高于ND组(P<0.01),额叶NCAM的免疫产物呈棕褐色,阳性表达主要位于额叶颗粒层细胞周缘的神经元胞浆中。结论:D-半乳糖致大鼠脑衰老造模成功;运动预处理对大鼠脑衰老和额叶NCAM的表达均未产生积极作用;衰老过程中进行有氧运动有效地延缓脑衰老,显著上调额叶NCAM的表达。更多还原

【Abstract】 Objective: Aging SD rats induced by injection of D- Galactose were intervened by aerobic exercise ahead of aging and during aging to explore the effect of aerobic exercise on brain aging and expression level of NCAM in frontal lobe. Methods: 60 3- month- old male SD rats were randomly divided into groups SD(aerobic exercise ahead of aging group),ND(aging group),NNa(saline control group) and NDs( aerobic exercise during aging group),n = 15.SOD activity,GSH- Px activity and MDA contents in cerebral cortex were determined. Expression level of NCAM in frontal lobe was determined by real- time PCR,western blotting and immunohistochemistry. Results: Group ND,compared with group NNa rats,revealed a lot of obvious aging signs,such as lethargy,loss of appetite,slowness,curly brown hair and shedding; SOD and GSH- Px activity of group ND rats were significantly lower than group NNa(P < 0.01),MDA content was significantly more than that of group NNa( P < 0. 01),SOD and GSH- Px activity and MDA content of group ND rats had no significant difference from group ND(P > 0. 05),SOD and GSH- Px activity of group NDs rats were very significantly higher than those of group ND(P < 0. 01),MDA content was significantly less than that of group ND(P < 0. 01); mRNA and protein expression level of NCAM gene in frontal lobe of group ND rats were significantly lower than those of group NNa( P < 0. 01). Compared with group ND,mRNA and protein expression level of NCAM gene in frontal lobe of group SD rats had no significant difference(P > 0. 05) while mRNA and protein expression level of NCAM gene in frontal lobe of group NDs rats were significantly higher than those of group ND( P < 0. 01. Immunoreactivities of NCAM in frontal lobe were brown,mainly located in neuronal cytoplasm beside the granular cells.Conclusion: Injection of D- galactose induced brain aging model rats successful; Aerobic exercise ahead of aging did not have a favorable impact on brain aging and aerobic exercise during aging showed an effective impact on delaying brain aging; Aerobic exercise ahead of aging did not have a favorable impact on expression level of NCAM in frontal lobe and aerobic exercise during aging could significantly increase expression level of NCAM in frontal lobe.更多还原