【摘要】 目的:观察长期耐力训练及限食对老龄大鼠骨骼肌线粒体氧化及抗氧化水平的影响,比较其单独及协同作用,为"线粒体衰老"学说提供一定的理论依据。方法:32只17月龄雄性SD大鼠分为4组:安静组(Control,C)、限食组(Caloric-Restricted,CR)、运动组(Exercise,E)和限食加运动组(Caloric-restricted and Exercise,E+CR),训练方式为跑台运动,中等运动强度(64%VO2max,15m/min,60分钟/天,每周5天),限食摄入的标准为正常摄入组的60%,共训练及限食12周,相同月龄对照组正常饲养。12周后于末次训练后取大鼠骨骼肌分别进行线粒体氧化损伤水平及抗氧化水平测定。结果:CR组、E组和CR+E组骨骼肌线粒体丙二醛(malondialdehyde,MDA)含量显著降低,锰超氧化物歧化酶(manganese-containing superoxide dismutase,MnSOD)活性显著增加,谷胱甘肽过氧化物酶(glutathion peroxidase,GSH-PX)活性显著增加;E组和CR+E组骨骼肌线粒体过氧化氢酶(catalase,CAT)活性显著增加。结论:耐力训练提高机体的抗氧化水平,同时使细胞机能节省化,耗氧量相对下降而减少了自由基的产生,限食减弱了机体的氧化应激,减少了自由基的产生,阻止了脂质过氧化,同时限食动员了一系列的适应性的网络防御机制,增加了抗氧化水平,加强了防御。耐力运动在机体抗氧化能力上明显强于限食作用,而耐力运动与限食的协同作用对某些抗氧化酶的影响强于其单独作用的影响。更多还原

【Abstract】 Objective: We observed in aged rats with long- term endurance training and caloric restriction on skeletal muscle mitochondrial oxidation and antioxidant levels,and compare their individual and synergy effect,to provide certain theoretical basis for the theory "mitochondrial aging". Methods: 32 adult male 17month old SD rats were divided into 4 equal groups: control,caloric- restricted,exercise,exercise and caloric- restricted. Exercise and caloric- restricted groups were trained for 12 months by running on a treadmill( 64% VO2max; 15 m /min,60 min / day; 5 days / week),while caloric- restricted group were maintained on 60% caloric intake of normal caloric intake for 12 months. Measuring mitochondrial oxidative damage and antioxidant levels in rat skeletal muscle after the last training of 12 weeks. Results: the malondialdehyde( MDA) content in decreased significantly( P < 0. 05),Manganese superoxide dismutase( manganese- containing superoxide dismutase,MnSOD) activity increased significantly( P < 0. 05) and glutathione peroxidase( glutathion peroxidase,gsh- px) activity increased significantly( P < 0. 05) in CR group,E and CR + E group skeletal muscle mitochondria. The hydrogen peroxide enzyme( catalase,CAT) activity increased significantly( P < 0. 05) in E and CR + E group skeletal muscle mitochondria. Conclusions: On the one hand,endurance training improves the body’s antioxidant ability,on the other hand,endurance training saves cell function and declines oxygen consumption relatively and reduces the production of free radicals. CR weakens the oxidative stress and reduces the production of free radicals and prevents the lipid peroxidation. while CR mobilizes a series of adaptive network defense mechanism and increases antioxidant levels and strengthens the defense. Endurance exercise is significant stronger than the effect of caloric restriction on the antioxidant ability. The synergy of endurance training and CR is stronger than the effect of their individual effects about certain antioxidant enzymes.更多还原