The Mechanism Of Exercise-induced Reactive Oxygen Species By NADPH Oxidase Pathway

The Exercise-Induced Oxidative Stress has been researched for almost30years. In the first20years of researching resulting from ROS produced by exercise, a variety of theories that movement induces ROS mechanism have been formed gradually and the dominant one is Mitochondrial Doctrine, on which some recent studies began to have doubt though. NADPH oxidase used to be considered as proprietary phagocytic cells enzymes, but recently was found existing in many other cells. Besides, ROS produced by this kind of enzyme plays regulation role of signal transmission and gene expression in the cell. Increasing evidence shows that NADPH oxidase has been also involved in generating the skeletal muscles ROS induced by movement. Based on the result of recent studies, this research set the hypotheses that NADPH oxidase is the main way to improve ROS induced by exercise.Methods:60mice are randomly divided into six groups of10mice:(1) the control group (group C),10mice;(2) control+drug group (group CA);(3) training swimming group (group T);(4) training+drug group (group TA);(5) load swimming group(group OT);(6) load swimming training group+drug group (group OTA). Load swimming for3%weight, once a day,90minutes,6times a week,4weeks in total. Before the last two training, inject the NADPH oxidase inhibitors apocynin (10mg/kg weight) in the tail intravenous and get the sample over24hours after the final training.Results:1. After four weeks of training,24h after the last exercise, serum CK activity in each training group increased (P<0.05), and the load group is higher than non-load group. Hb concentration in each training group increased (P<0.05). The content of skeletal muscle Gln in each training group has no significant differences.2. Over24h after the last exercise, skeletal muscle ROS in group T and group OT increased significantly (P<0.01), and ROS in group OT increased much higher than the one in the group T (P<0.05); Compared group TA with group T, group OTA with group OT, ROS in skeletal muscle decreased significantly (P<0.01) and no significant difference compared with the control group (P>0.05).3. Over24h after the last exercise, MDA content in skeletal muscle of group T and group OT decreased (P<0.05). Group OT increased significantly (P<0.01). Group OTA decreased significantly (P<0.01) compared with group OT. After four weeks of training, SOD activity in skeletal muscle of group OT and group OTA increased significantly (P<0.05). Group T and group TA had no significant change (P>0.05).Conclusion:1.4weeks’ swimming training with different loads, over24h after the last exercise, skeletal muscle ROS increased significantly, and the change is more obvious in lower looading training.After imposed by the NADPH oxidase inhibitor, the reasult is revesed.It is indicated that increasing of skeletal muscle ROS induced by two kinds of load training is generated through NADPH oxidase.2. Over24h after the last exercise, MDA in skeletal muscle in the high-load training group increased, while the one in low-load group decreased. SOD activity in skeletal muscle in high load exercise increased, suggesting that appropriate low-intensity exercise promotes to clear MDA metabolized from ROS.3. After4weeks’ training, Hb level in the mice of each group increased, suggesting that long-term aerobic training promotes to improve the transport oxygen capacity.4. The method of detection of DCFH-DA fluorescence probe in intracellular ROS can be effectively used to detect the homogenate ROS of skeletal muscle.