论文部分内容阅读
目的:研究急性运动诱导线粒体活性氧(ROS)生成的过程中,线粒体内解偶联蛋白(UCPs)介导的温和解偶联(milduncoupling)和抗氧化酶这两种抗氧化体系可能的分工与协同关系及其生物学意义。方法:以SD大鼠3级递增负荷跑台运动为实验模型,分别选取安静态、运动45min、90min、120min和150min为实验观察点(timecourse),测定骨骼肌线粒体ROS生成和脂质过氧化水平(MDA)、线粒体Mn-SOD酶活性、Mn-SOD和解偶联蛋白3(UCP-3)mRNA及蛋白表达。结果:运动过程中ROS生成呈先上升后下降的变化趋势,在运动120min达到峰值,其中运动45min、90min、120min和150min时均较安静时呈显著性升高(分别为P<0.05、P<0.001、P<0.001和P<0.01),150min时下降并具有显著性(P<0.001)。线粒体MDA含量总体呈上升趋势,但变化无显著性。运动过程中Mn-SOD酶活性及其mRNA和蛋白表达水平均无显著性变化,而UCP-3mRNA和蛋白表达水平总体呈上升趋势。其中UCP-3mRNA在运动至90min、120min、150min时较安静时均呈显著性升高(分别为P<0.001、P<0.01和P<0.01),其蛋白表达水平相对滞后一个时间段,运动120min、150min时较安静时显著升高(均为P<0.001)。结论:长时间运动过程中,以UCP-3的先行诱导表达对骨骼肌线粒体氧化还原状态进行调节,相对于Mn-SOD的抗氧化作用,UCP-3的诱导表达是运动中抗氧化的“早期事件”。
OBJECTIVE: To study the possible division of labor between mitochondrial reactive oxygen species (ROS) and acute uncoupling protein (UCPs) -mediated mild uncoupling and antioxidant enzymes in mitochondrial reactive oxygen species (ROS) Synergetic relationship and its biological significance. Methods: The rats were randomly divided into three groups: SD rats, three-step incremental treadmill exercise test as model, and static state, exercise 45min, 90min, 120min and 150min were selected as experimental time points to determine ROS production and lipid peroxidation (MDA), mitochondrial Mn-SOD activity, Mn-SOD and uncoupling protein 3 (UCP-3) mRNA and protein expression. Results: During the exercise, the production of ROS increased first and then decreased, reaching its peak at 120 min of exercise. The activities of ROS increased significantly at 45 min, 90 min, 120 min and 150 min (P <0.05, P < 0.001, P <0.001 and P <0.01) and decreased significantly at 150 min (P <0.001). The mitochondrial MDA content generally showed an upward trend, but the change was insignificant. Mn-SOD activity, mRNA and protein expression of Mn-SOD had no significant changes during exercise, while the expression of UCP-3 mRNA and protein showed an overall upward trend. The expression of UCP-3mRNA increased significantly (P <0.001, P <0.01 and P <0.01, respectively) at 90min, 120min and 150min after exercise, and the expression of UCP-3mRNA lags behind for a period of 120min , 150min was significantly higher when quiescent (both P <0.001). CONCLUSION: During long-term exercise, the mitochondrial redox status of skeletal muscle was regulated by the pro-UCP-3 induced expression. Compared with the antioxidant activity of Mn-SOD, the induced expression of UCP-3 was an early antioxidant event".