HIF-1α在急性运动介导小鼠骨骼肌Nrf2及抗氧化酶表达中的作用
Role of HIF-1α in the Expression of Nrf2 and Antioxidase in Skeletal Muscle of Mice Induced by Acute Exercise

摘要：目的：探究HIF-1α在急性运动介导骨骼肌Nrf2与抗氧化蛋白表达中的作用。方法：野生鼠和HIF-1α转基因鼠各20只，各自随机分为安静组和运动组，每组10只，共4组。运动组小鼠进行一次运动时间为3 h的跑台有氧运动（坡度为10%，速度为14 m/min）。正式实验前3天，运动组小鼠进行每天20 min适应性的跑台运动。运动组完成运动方案后，即刻取材。Western blot法测定骨骼肌胞浆蛋白中Nrf2、磷酸化Nrf2（Ser40）、Keap1及部分抗氧化蛋白和骨骼肌核蛋白中Nrf2含量。结果：1. 安静状态下，转基因鼠与野生鼠相比， Nrf2 mRNA表达、p-Nrf2、SOD2蛋白表达显著性增加（P<0.05）。2. 与野生安静组相比，野生运动组Nrf2 mRNA表达和p-Nrf2含量显著性增加（P<0.05），Keap1和HO-1胞浆蛋白表达显著性下降（P<0.05）。3. 转基因运动组与转基因安静组相比， Nrf2、核Nrf2 、NQO1和SOD2蛋白显著性增加（P<0.05），Keap1（P<0.05）、GPx-1（P<0.01）显著性低于安静组；转基因鼠运动组与野生鼠运动组相比，Nrf2 mRNA和Nrf2蛋白表达显著性增加（P<0.05），HO-1、NQO1、SOD1、 SOD2和GR显著或非常显著性增加（P<0.05、P<0.01）。结论：适当的HIF-1α水平对有氧运动小鼠骨骼肌Nrf2及抗氧化酶的表达起着积极的促进作用。
Abstract: Purpose: The purpose of this study was to explore the effect of HIF-1α in the expression of Nrf2 and antioxidant proteins in skeletal muscle of mice induced by acute exercise. Methods: Twenty C57BL/ 6J wide mice and 20 HIF-1α high-expression mice were randomly divided into control group and exercise group respectively. After 3-day 20 min adaptive exercise, the mice of exercise groups finished 3 hours treadmill running at a speed of 14m/min with a slope of 10%. They were sacrificed immediately after the exercise program. The expressions of Keap1, Nrf2, p-Nrf2(Ser40) and some antioxidant proteins in skeletal muscle cytoplasm and Nrf2 in nucleus were measured by Weston blot. Results: 1) Compared with the wild mice, the Nrf2 mRNA and the expression of p-Nrf2 and SOD2 in cytoplasm of HIF-1α high-expression mice increased significantly in rest state; 2) Compared with wild mice of control group, the Nrf2 mRNA and p-Nrf2 expressions of wild mice of exercise group increased (P < 0.05), the Keap1 and HO-1 decreased (P < 0.05); 3) Compared with HIF-1α high-expression mice of control group, the Nrf2 in cytoplasm and nucleus, NQO1, SOD2 of HIF-1α high-expression mice of control group increased (P < 0.05), and Keap1 (P<0.05) and GPx-1 (P<0.01) decreased; in both exercise groups, Nrf2 mRNA and protein expressions, HO-1, NQO1, SOD1, SOD2 and GR of HIF-1α high-expression mice were higher than those of wild mice (Ps < 0.05). Conclusions: Proper level of HIF-1α plays a positive role in promoting the expression of Nrf2 and antioxidant enzymes in skeletal muscle of aerobic exercise mic