Effect of endurance training on accumulation of age-associated mitochondrial DNA deletions in old rats.

耐力训练对老年大鼠年龄相关线粒体 DNA 缺失积累的影响。

基本信息

批准号：
10680015
负责人：
KUNO Shinya
金额：
$ 2.11万
依托单位：
University of Tsukuba
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

It has been proposed that age-associate decline of muscle metabolism of energy product are resulted from the accumulation of mitochondrial DNA (mtDNA) deletions in several species (Linnane et al., 1989). However, age-associated mt DNA deletions have not been successfully detected in the rat skeletal muscles (Filser et al., 1997). Exercise has been known to improve the muscle metabolism and then may have a benefit to prevent the accumulation of mtDNA deletions with age. As long as we know, little has been known about the effects of exercise on the accumulation of mtDNA deletions so far. The purpose of this study was to detect the age-associated mtDNA deletions in the rat skeletal muscles, and to examine whether endurance training effects on the accumulation of mtDNA deletions with age in different type of skeletal muscle. We used forty five Wistar male rats (10 wks : n=29, 90 wks : n=16) in this study. Young rats were divided into three groups (20 m/min training group, 30 m/min training … More group and control group) and old rats were divided into two groups (20 m/min training group and control group). The training protocol consisted of 60 min, 5 days/wk for 10 wks. MtDNA of m. soleus (SOL) and m.plantaris (PLA) were analyzed by polymerase chain reaction (PCR). The presence of age-associated 4.8-kb deletion (common deletion) and the number of deletion products detected per rat were examined. The presence of common deletion was evaluated by the number of rats in each group and the number of deletion was estimated by counting the deletion products visualized per rat. Two of the young rats (6.9%) and nine of the old rats (56.3%) had common deletion in SOL, while two of the young rats (6.9%) and fifteen of the old rats (93.8%) had in PLA. No effect of the endurance training on the presence of common deletion was seen in either the young group or the old group. In the old group, the presence of common deletion was higher in PLA than that in SOL. The numbers of deletion in PLA increased with age significantly (p<0.01). However the numbers of deletion in SOL showed no significant difference between the young and the old groups. The training effect on the numbers of deletion was not observed in any groups. In the young group, the number of mtDNA deletion products in SOL was higher than that in PLA. In the old group, however, the value was lower in SOL than in PLA.In conclusion, we could detect the accumulation of age-associated mtDNA deletions of the rat skeletal muscles, and observed no endurance training effect on that in this study. Moreover, the accumulation of mtDNA deletions can be specific according to fiber types. Less

已经提出，能量产物肌肉代谢的年龄相关下降是由于几种物种中线粒体DNA（mtDNA）缺失的积累而产生的（Linnane等，1989）。然而，在大鼠骨骼肌中尚未成功检测到与年龄相关的MT DNA缺失（Filser等，1997）。众所周知，运动可以改善肌肉代谢，然后可能有好处，以防止随着年龄的增长而积累。只要我们知道，到目前为止，对运动对mtDNA缺失的积累的影响知之甚少。这项研究的目的是检测大鼠骨骼肌中与年龄相关的mtDNA缺失，并检查耐力训练是否对不同类型的骨骼肌年龄的mtDNA缺失对积累的影响。在这项研究中，我们使用了45只Wistar雄性大鼠（10 wks：n = 29，90 wks：n = 16）。将年轻大鼠分为三组（20 m/min训练组，30 m/min训练…更多组和对照组），而老鼠分为两组（20 m/min训练组和对照组）。训练方案包括60分钟，5天/周的10周。 m的mtDNA。通过聚合酶链反应（PCR）分析了比目鱼（Sol）和M. plantaris（PLA）。检查了与年龄相关的4.8-KB缺失（常见缺失）和每只大鼠检测到的缺失产物的数量。通过每组大鼠的数量评估了共同缺失的存在，并通过计算每只大鼠可视化的缺失产物来估计缺失的数量。其中两只年轻大鼠（6.9％）和九只老鼠（56.3％）在SOL中有共同的缺失，而PLA中有两只年轻大鼠（6.9％）（6.9％）和15只老鼠（93.8％）。在年轻群体或旧群体中，耐力训练对存在常见缺失的影响。在旧组中，PLA中常见缺失的存在高于SOL。 PLA中缺失的数量随着年龄的增长而增加（p <0.01）。但是，SOL中缺失的数量显示出年轻组和旧组之间没有显着差异。在任何组中均未观察到对缺失数量的训练效果。在年轻组中，SOL中的mtDNA缺失产物的数量高于PLA中的MTDNA缺失。然而，在旧组中，Sol的值低于PLA。总之，我们可以检测到大鼠骨骼肌与年龄相关的mtDNA缺失的积累，并且在这项研究中观察到对此没有耐力训练效应。此外，根据纤维类型可以特异性MTDNA缺失的积累。较少的