Physical exercise improves body weight gain and liver function in malnourished rats without disturbing the redox balance

ABSTRACT Objective To study the relationship between exercise and malnourishment because recent evidence suggests that exercise can cause the beneficial adaptation of antioxidant systems, whereas malnourishment can cause harmful adaptation of these systems. Methods Thirty-two female Fischer rats were equally divided into Sedentary Control, Trained Control, Sedentary Malnourished and Trained Malnourished groups. The training protocol consisted of swimming for 30 minutes continuously for 5 days/week for 8 weeks. Results It was demonstrated that aspartate aminotransferase and alanine aminotransferase activities increased in malnourished rats, but physical training reversed these effects by lowering the raised levels. The glutathione level was diminished by malnourishment whereas physical training increased the levels of liver carbonyl protein and increased the levels of thiobarbituric acid reactive substances that were diminished by malnourishment. In addition, Trained Malnourished rats had a higher average body weight than Sedentary Malnourished ones (62.77g vs. 55.08g, respectively). Conclusion The data show that exercise was able to reverse or reduce damage caused by malnourishment, such as weight loss and liver dysfunction by a pathway independent of the participation of enzymes involved in antioxidant defense and that there is no interaction between exercise and malnutrition.摘要 目的：本研究旨在探讨运动与营养不良之间的关联，因近期研究证据表明，运动可引发抗氧化系统的有益适应性变化，而营养不良则会导致该系统产生有害适应性改变。 方法：将32只雌性Fischer大鼠均分为4组：久坐对照组（Sedentary Control）、运动对照组（Trained Control）、久坐营养不良组（Sedentary Malnourished）与运动营养不良组（Trained Malnourished）。训练方案为每周5天、每日连续游泳30分钟，持续8周。 结果：研究证实，营养不良大鼠的天冬氨酸氨基转移酶（aspartate aminotransferase）与丙氨酸氨基转移酶（alanine aminotransferase）活性均升高，而运动训练可通过降低上述升高的酶活性逆转该变化。营养不良可降低谷胱甘肽（glutathione）水平，而运动训练则可提升肝羰基蛋白（liver carbonyl protein）水平，以及原本因营养不良而降低的硫代巴比妥酸反应物质（thiobarbituric acid reactive substances）水平。此外，运动营养不良组大鼠的平均体重要高于久坐营养不良组（分别为62.77g与55.08g）。 结论：本研究数据显示，运动可通过不依赖抗氧化防御相关酶参与的通路，逆转或减轻营养不良引发的体重减轻、肝功能异常等损伤；且运动与营养不良之间不存在交互作用。