Background An acute bout of exercise induces an inflammatory response characterized by increases in several cytokines. Caffeine ingestion could modify this inflammatory response. The aim of this study was to determine the effects of caffeine supplementation on plasma levels of cytokines, mainly IL-10 and IL-6, in response to exercise. Methods In a randomized, crossover, double-blinded study design, thirteen healthy, well-trained recreational male athletes performed, on two different occasions, a treadmill exercise test (60 min at 70% VO 2 max) after ingesting 6 mg/kg body mass of caffeine or placebo. Blood samples were taken before exercising, immediately after finishing and 2 h after finishing the exercise. Plasma concentrations of IL-10, IL-6, IL-1β, IL-1ra, IL-4, IL-8, IL-12 and IFN-γ, adrenaline, cortisol and cyclic adenosine monophosphate (cAMP) were determined. The capacity of whole blood cultures to produce cytokines in response to endotoxin (LPS) was also determined. Changes in blood variables were analyzed using a time (pre-exercise, post-exercise, recovery) x condition (caffeine, placebo) within-between subjects ANOVA with repeated measures. Results Caffeine supplementation induced higher adrenaline levels in the supplemented participants after exercise (257.3 ± 53.2 vs. 134.0 ± 25.7 pg·mL − 1 , p = 0.03) and higher cortisol levels after recovery (46.4 ± 8.5 vs. 32.3 ± 5.6 pg·mL − 1 , p = 0.007), but it did not influence plasma cAMP levels ( p = 0.327). The exercise test induced significant increases in IL-10, IL-6, IL-1ra, IL-4, IL-8, IL-12 and IFN-γ plasma levels, with IL-6 and IL-10 levels remaining high after recovery. Caffeine supplementation influenced only IL-6 (3.04 ± 0.40 vs. 3.89 ± 0.62 pg·mL − 1 , p = 0.003) and IL-10 (2.42 ± 0.54 vs. 3.47 ± 0.72 pg·mL − 1 , p = 0.01) levels, with higher concentrations after exercise in the supplemented condition. No effect of caffeine was observed on the in vitro stimulated cytokine production. Conclusions The results of the present study indicate a significant influence of caffeine supplementation increasing the response to exercise of two essential cytokines such as IL-6 and IL-10. However, caffeine did not influence changes in the plasma levels of other cytokines measured and the in vitro-stimulated cytokine production.

中文翻译：

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在跑步机运动测试中，补充咖啡因会导致更高的 IL-6 和 IL-10 血浆水平

背景 剧烈运动会诱发炎症反应，其特征是几种细胞因子的增加。摄入咖啡因可以改变这种炎症反应。本研究的目的是确定补充咖啡因对运动后细胞因子（主要是 IL-10 和 IL-6）血浆水平的影响。方法 在一项随机、交叉、双盲研究设计中，13 名健康、训练有素的休闲男性运动员在摄入 6 mg/kg 体重后，在两个不同场合进行了跑步机运动测试（70% VO 2 max 下 60 分钟）大量的咖啡因或安慰剂。在运动前、运动结束后立即和运动结束后 2 小时采集血样。IL-10、IL-6、IL-1β、IL-1ra、IL-4、IL-8、IL-12 和 IFN-γ、肾上腺素、测定了皮质醇和环磷酸腺苷 (cAMP)。还测定了全血培养物响应内毒素 (LPS) 产生细胞因子的能力。使用时间（运动前、运动后、恢复）x 条件（咖啡因、安慰剂）在受试者之间进行方差分析并重复测量来分析血液变量的变化。结果 补充咖啡因导致运动后补充参与者的肾上腺素水平升高（257.3 ± 53.2 vs. 134.0 ± 25.7 pg·mL − 1，p = 0.03）和恢复后皮质醇水平升高（46.4 ± 8.5 vs. 32.3·± 5.6 pgmL） − 1 , p = 0.007)，但不影响血浆 cAMP 水平 (p = 0.327)。运动试验导致 IL-10、IL-6、IL-1ra、IL-4、IL-8、IL-12 和 IFN-γ 血浆水平显着升高，恢复后 IL-6 和 IL-10 水平保持高水平. 补充咖啡因仅影响 IL-6（3.04 ± 0.40 对 3.89 ± 0.62 pg·mL - 1，p = 0.003）和 IL-10（2.42 ± 0.54 对 3.47 ± 0.72 pg·mL - 1，p = 0）水平。 ，在补充条件下运动后浓度更高。没有观察到咖啡因对体外刺激的细胞因子产生的影响。结论 本研究的结果表明，补充咖啡因可显着提高两种基本细胞因子（如 IL-6 和 IL-10）对运动的反应。然而，咖啡因不影响其他细胞因子的血浆水平变化和体外刺激的细胞因子产生。在补充条件下运动后浓度更高。没有观察到咖啡因对体外刺激的细胞因子产生的影响。结论 本研究的结果表明，补充咖啡因可显着提高两种基本细胞因子（如 IL-6 和 IL-10）对运动的反应。然而，咖啡因不影响其他细胞因子的血浆水平变化和体外刺激的细胞因子产生。在补充条件下运动后浓度更高。没有观察到咖啡因对体外刺激的细胞因子产生的影响。结论 本研究的结果表明，补充咖啡因可显着提高两种基本细胞因子（如 IL-6 和 IL-10）对运动的反应。然而，咖啡因不影响其他细胞因子的血浆水平变化和体外刺激的细胞因子产生。