衰老和有氧运动对大鼠肝脏线粒体DNA突变的影响

当前研究表明机体衰老与线粒体功能下降关系密切.其中线粒体DNA突变可能是线粒体功能下降与活性氧产生增多的关键因素之一.本研究检测到22月龄大鼠肝脏线粒体DNA出现4834bp缺失,3个月的游泳训练明显降低同龄大鼠线粒体DNA 4834bp缺失发生率.研究同时发现老年大鼠肝脏线粒体复合体I和IV活性明显低于年轻大鼠,而有氧运动可显著升高老年运动大鼠线粒体酶活性.结果表明有氧运动能够减少线粒体DNA突变发生,进而改善线粒体功能,这可能是有氧运动提高线粒体功能,延缓衰老的重要机制.

The Effect of Aging and Aerobic Exercise on Mitochondrial DNA Deletions in Rat Liver

Many studies indicate that aging is associated with the alteration of mitochondrial function. Mitochondrial DNA mutation probably plays the important role in the decrease of mitochondrial function and the increase of reactive oxygen species. In present experiment, we detected the 4834bp deletions of mitochondrial DNA in aged rat (22 months old) liver using PCR technique.Three-month swimming training reduced the frequency of mitochondrial DNA deletions in 22 months old rats. The activities of mitochondrial respiratory chain complex I and IV in aged rats' liver decreased significantly compared with that in young rats. Both of two complexes activities increased significantly in exercise training aged rats compared with aged rats. The results indicate that aerobic exercise can reduce the frequency of mitochondrial DNA deletions and preserve mitochondrial functions of rats at old age.