Lira Fábio S, Koyama Cristiane H, Yamashita Alex S, Rosa José C, Zanchi Nelo E, Batista Miguel L, Seelaender Marília C
Molecular Biology of the Cell Group, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
Cell Biochem Funct. 2009 Oct;27(7):458-61. doi: 10.1002/cbf.1594.
Skeletal muscle is the source of pro- and anti-inflammatory cytokines, and recently, it has been recognized as an important source of interleukin-6 (IL-6). Acute physical exercise is known to induce a pro-inflammatory cytokine profile in the plasma. However, the effect of chronic physical exercise in the production of pro- and anti-inflammatory cytokines by the skeletal muscle has never been examined. We assessed IL-6, TNF-alpha, IL-1beta and IL-10 levels in the skeletal muscle of rats submitted to endurance training. Animals were randomly assigned to either a sedentary group (S, n = 7) or an endurance exercise trained group (T, n = 8). Trained rats ran on a treadmill for 5 days week(-1) for 8 weeks (60% VO(2max)). Detection of IL-6, TNF-alpha, IL-1beta and IL-10 protein expression was carried out by ELISA. We found decreased expression of IL-1beta, IL-6, TNF-alpha and IL-10 (28%, 27%, 32% and 37%, respectively, p < 0.05) in the extensor digital longus (EDL) from T, when compared with S. In the soleus, IL-1beta, TNF-alpha and IL-10 protein levels were similarly decreased (34%, 42% and 50%, respectively, p < 0.05) in T in relation to S, while IL-6 expression was not affected by the training protocol. In conclusion, exercise training induced decreased cytokine protein expression in the skeletal muscle. These data show that in healthy rats, 8-week moderate-intensity aerobic training down regulates skeletal muscle production of cytokines involved in the onset, maintenance and regulation of inflammation, and that the response is heterogeneous according to fibre composition.
骨骼肌是促炎和抗炎细胞因子的来源，最近，它被认为是白细胞介素-6（IL-6）的重要来源。已知急性体育锻炼会在血浆中诱导促炎细胞因子谱。然而，慢性体育锻炼对骨骼肌产生促炎和抗炎细胞因子的影响从未被研究过。我们评估了接受耐力训练的大鼠骨骼肌中IL-6、肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）和白细胞介素-10的水平。动物被随机分为久坐组（S，n = 7）或耐力运动训练组（T，n = 8）。训练的大鼠每周在跑步机上跑5天，持续8周（60%最大摄氧量（VO₂max））。通过酶联免疫吸附测定（ELISA）检测IL-6、TNF-α、IL-1β和IL-10蛋白表达。我们发现，与S组相比，T组趾长伸肌（EDL）中IL-1β、IL-6、TNF-α和IL-10的表达降低（分别降低28%、27%、32%和37%，p < 0.05）。在比目鱼肌中，与S组相比，T组中IL-1β、TNF-α和IL-10蛋白水平同样降低（分别降低34%、42%和50%，p < 0.05），而IL-6表达不受训练方案影响。总之，运动训练导致骨骼肌中细胞因子蛋白表达降低。这些数据表明，在健康大鼠中，8周中等强度有氧训练下调了参与炎症发生、维持和调节的细胞因子的骨骼肌产生，并且根据纤维组成，反应是异质性的。
