Karimi Majd Somayeh, Gholami Mandana, Bazgir Behzad
Department of Physical Education and Sport Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Exercise Physiology Research Center, Life Style Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
Cell J. 2023 Feb 1;25(2):135-142. doi: 10.22074/cellj.2022.557440.1055.
Satellite cells play an important role in muscle regeneration, which this process can be affected by different genes including PAX7 and MyoD. Exercise training known as an important strategy for mediating the satellite cell's function. Therefore, the main purpose of the present study is to investigate the changes in PAX7 and MyoD protein expression in response to eccentric and concentric resistance exercise in healthy young men.
In this semi-experimental and cross-sectional study, 10 healthy men (age range 18-30 years old) participated. They were randomly divided into two equal groups (n=5) to perform one of two high-intensity eccentric or concentric knee extensions muscle contraction protocols. The contractions included a maximum of 12 sets of 10 repetitions, with a 30 second rest time interval between sets. PAX7 and MyoD protein expression was assessed using Immunohistochemistry analysis from the Vastus Lateralis muscle needle biopsy samples that have been taken 24 hours before and 3 to 4 hours after the end of the exercise protocol.
We observed that the PAX7 protein expression level increased significantly after eccentric (47.75%) and concentric (39.21%) (P=0.01) intervention. While, the MyoD protein expression level reduced (38.14%) significantly following acute eccentric resistance exercise (P=0.01).
It seems that eccentric or concentric muscular contraction modulates the expression of PAX7 and MyoD protein expression in the skeletal muscle, with further effects observed in eccentric resistance exercise.
卫星细胞在肌肉再生中发挥着重要作用，这一过程会受到包括PAX7和MyoD在内的不同基因的影响。运动训练是调节卫星细胞功能的一项重要策略。因此，本研究的主要目的是调查健康年轻男性在进行离心和向心阻力运动后PAX7和MyoD蛋白表达的变化。
在这项半实验性横断面研究中，10名健康男性（年龄范围18 - 30岁）参与其中。他们被随机分为两组（每组n = 5），分别进行两种高强度离心或向心膝关节伸展肌肉收缩方案中的一种。收缩动作包括最多12组，每组10次重复，组间休息30秒。使用免疫组织化学分析，对运动方案结束前24小时和结束后3至4小时采集的股外侧肌针吸活检样本中的PAX7和MyoD蛋白表达进行评估。
我们观察到，离心（47.75%）和向心（39.21%）干预后，PAX7蛋白表达水平显著升高（P = 0.01）。而急性离心阻力运动后，MyoD蛋白表达水平显著降低（38.14%）（P = 0.01）。
离心或向心肌肉收缩似乎会调节骨骼肌中PAX7和MyoD蛋白的表达，在离心阻力运动中观察到了更显著的影响。
