一次性力竭运动后大鼠心室肌蛋白质组的差异性表达

The Variability of Expression of Ventricular Muscle Proteome after a Single Bout of Exhaustive Exercise in Rats

目的:探讨力竭运动对大鼠心室肌蛋白质组表达的影响,初步筛选出对运动应激具有重要意义的心室肌目标蛋白质。方法:将10只雄性SD大鼠随机分为安静对照组和运动组(n=5)。运动组大鼠采用三级递增运动负荷跑台训练建立一次性力竭运动实验动物模型。取心室肌,提取心室肌组织全蛋白进行双向凝胶电泳(2-DE)分离。通过图像分析软件PD Quest进行分析后,选择运动后消失和表达量上调5倍或下调4/5以上的蛋白质点作为备选质谱鉴定蛋白点。结果:在电泳图谱上对照组平均检测到蛋白质点332±17个,运动组平均检测到347±22个。运动后共有47个蛋白质点发生了变化:5个点在运动后消失;表达量上调3倍以上的点有28个,下调2/3以上的点有14个,其中上调5倍以上的点14个,下调4/5以上的点4个。对6个备选蛋白质点进行了质谱鉴定,共鉴定出心肌α-肌球蛋白重链、原肌球蛋白-1、甘露糖结合蛋白C前体、腈水解酶和一个未知的分子量为21kD的蛋白质。结果表明,力竭运动后大鼠心室肌蛋白质组发生了明显变化;本研究为寻找新的运动性疲劳的生物标志物提供了新的思路。

Objective To probe into the mechanism of the exercise-induced fatigue and screen out certain meaningful proteins responsive to exercise. Methods Ten rats were randomly divided into control group （n = 5） and exercise group （n= 5）. After 3-day adaptive treadmill training, the rats in exercise group were running on treadmill with Bedford 3-grade incremental protocol until exhaustion, and then were killed for extracting the total protein of ventricular muscle using two-dimensional electrophoresis in combination with immobilized pH gradients separation. The disappeared protein spots and spots with differential expression volume more than 5 times were selected for mass spectra （MS） identification. Results and Conclusion In electrophoresis map, the average number of detected protein spots in control group and exercise group was 332±17 and 347± 22, respectively. After exercise, 47 protein spots changed. 5 disappeared; 28 increased expression more than 3 times; 14 decreased expression more than 2/3. 6 protein spots were selected for MS identification, and 6 types of proteins, such as myosin-6, tropomyosin-1 alpha chain, mannose-binding protein C precursor, the member 2 of nitrilase family and an unknown protein with 21 kD were identified. The results indicated the marked changes in myocardium proteome after exhaustive exercise. Further study on the tropomyosin-1, mannose-binding protein C precursor and the member 2 of nitrilase family was needed in the field of sports medicine. They could be the ideal biomarker for investigating exercise-induced fatigue.