目的:一些组织产生和释放白细胞介素-6(IL-6),以响应β2-肾上腺素能刺激与选择性激动剂(β2-激动剂)。此外,运动刺激肌肉IL-6的产生,但β2激动剂是否与运动相关地调节人骨骼肌中IL-6的产生和释放仍有待澄清。因此,我们调查了在静息和从抵抗运动中恢复的瘦年轻男性中,对β2激动剂沙丁胺醇的腿部IL-6释放的反应。
方法:本研究采用随机对照交叉设计,12名男性服用沙丁胺醇(16毫克)或安慰剂4天,然后是最后一次剂量(24毫克)在运动前1½小时给药。在股四头肌阻力运动恢复之前和1/2-5小时测量动脉和股静脉血浆IL-6以及股动脉血流。此外,运动后1/2和5小时收集股外侧肌活检,以测定IL-6和肿瘤坏死因子(TNF)-α的mRNA水平。
结果:沙丁胺醇的平均腿部IL-6释放量比安慰剂高1.7倍(p=0.01),沙丁胺醇和安慰剂为138±76和79±66pgmin-1(平均值±SD),分别,但在休息时和运动后的特定采样点内,IL-6释放在治疗之间没有显着差异。运动后1/2和5小时,沙丁胺醇的肌肉IL-6mRNA比安慰剂高1.5和1.7倍(p=0.001),分别,而对于TNF-αmRNA没有观察到显著的治疗差异。
结论:高剂量的选择性β2激动剂沙丁胺醇的β2-肾上腺素能刺激,在连续4次每日剂量之前,诱导骨骼肌中IL-6的转录,以响应抗阻运动,并增加瘦个体的肌肉IL-6释放。
OBJECTIVE: Several tissues produce and release interleukin-6 (IL-6) in response to
beta2 -adrenergic stimulation with selective agonists (
beta2 -agonists). Moreover, exercise stimulates muscle IL-6 production, but whether
beta2 -agonists regulate skeletal muscle production and release of IL-6 in humans in association with exercise remains to be clarified. Thus, we investigated leg IL-6 release in response to
beta2 -agonist salbutamol in lean young men at rest and in recovery from resistance exercise.
METHODS: The study employed a randomized controlled crossover design, where 12 men ingested either salbutamol (16 mg) or placebo for 4 days, followed by the last dose (24 mg) administered 1½ h before exercise. Arterial and femoral venous plasma IL-6 as well as femoral artery blood flow was measured before and ½-5 h in recovery from quadriceps muscle resistance exercise. Furthermore, vastus lateralis muscle biopsies were collected ½ and 5 h after exercise for determination of mRNA levels of IL-6 and Tumor Necrosis Factor (TNF)-α.
RESULTS: Average leg IL-6 release was 1.7-fold higher (p = 0.01) for salbutamol than placebo, being 138 ± 76 and 79 ± 66 pg min-1 (mean ± SD) for salbutamol and placebo, respectively, but IL-6 release was not significantly different between treatments within specific sampling points at rest and after exercise. Muscle IL-6 mRNA was 1.5- and 1.7-fold higher (p = 0.001) for salbutamol than placebo ½ and 5 h after exercise, respectively, whereas no significant treatment differences were observed for TNF-α mRNA.
CONCLUSIONS: Beta2 -adrenergic stimulation with high doses of the selective
beta2 -agonist salbutamol, preceeded by 4 consecutive daily doses, induces transcription of IL-6 in skeletal muscle in response to resistance exercise, and increases muscle IL-6 release in lean individuals.