Wolach Baruch, Gavrieli Ronit, Ben-Dror Shiri Geffen, Zigel Levana, Eliakim Alon, Falk Bareket
Department of Pediatrics, The Laboratory for Leukocyte Function, Meir General Hospital, Kfar Saba, Israel.
Med Sci Sports Exerc. 2005 Jun;37(6):949-54.
Intense exercise affects the immune system, increasing the susceptibility of athletes to viral and bacterial infections. We have previously shown a significant decrease of fMLP-neutrophil migration 24 h after aerobic exercise. In this study we aimed to look at the differential effect of different chemoattractants on neutrophil migration following aerobic exercise, to determine the recovery time, and to better understand the role of the cell skeleton behind the impaired chemotaxis.
Sixteen female volunteers aged 22-30 yr were tested before, 24, and 48 h after aerobic exercise (30 min running at 70% (.)VO(2max). The submaximal exercise test was conducted a week after the (.)VO(2max) test. We studied the membrane cell receptor response to fMLP, IL-8, and C5a, which have specific ligand-receptor pathways. Further, we studied the cytoskeletal response by investigating the cell polarization and the F-actin polymerization.
Significant decrease of the neutrophil net chemotaxis was detected with fMLP, IL-8 and C5a, 24 h after exercise (50 +/- 5%, P = 0.0001; 48 +/- 12%, P = 0.0015; and 32 +/- 11%, P = 0.011, respectively). Complete recovery was observed within 48 h with all chemoattractants. Normal neutrophil random migration and F-actin polymerization were found. Decreased neutrophil polarization was detected (46 +/- 6% vs 22 +/- 8% of polarized cells, before and after effort, respectively; P = 0.004). Correlation between polarization and chemotactic migration was found (r = 0.945; P = 0.001).
The impaired chemotactic response, observed 24 h after exercise, was similar using different chemoattractants. This finding indicates a possible exercise-induced effect on a common factor at the ligand-receptor level. The abnormal cell polarization indicates skeletal dysfunction that should be further investigated and elucidated. The normal fMLP-stimulated-F-actin polymerization reflects an adequate pathway of signal transduction for the formyl peptide.
剧烈运动影响免疫系统，增加运动员对病毒和细菌感染的易感性。我们之前已表明有氧运动24小时后fMLP诱导的中性粒细胞迁移显著减少。在本研究中，我们旨在观察有氧运动后不同趋化因子对中性粒细胞迁移的不同影响，确定恢复时间，并更好地理解趋化性受损背后细胞骨架的作用。
16名年龄在22 - 30岁的女性志愿者在有氧运动前、运动后24小时和48小时接受测试（以70%最大摄氧量进行30分钟跑步）。次极量运动测试在最大摄氧量测试一周后进行。我们研究了膜细胞受体对fMLP、IL - 8和C5a的反应，它们具有特定的配体 - 受体途径。此外，我们通过研究细胞极化和F - 肌动蛋白聚合来研究细胞骨架反应。
运动后24小时，用fMLP、IL - 8和C5a检测到中性粒细胞净趋化性显著降低（分别为50±5%，P = 0.0001；48±12%，P = 0.0015；32±11%，P = 0.011）。所有趋化因子在48小时内均观察到完全恢复。发现中性粒细胞随机迁移和F - 肌动蛋白聚合正常。检测到中性粒细胞极化降低（运动前后极化细胞分别为46±6%和22±8%；P = 0.004）。发现极化与趋化性迁移之间存在相关性（r = 0.945；P = 0.001）。
运动后24小时观察到的趋化反应受损，使用不同趋化因子时情况相似。这一发现表明运动可能在配体 - 受体水平对一个共同因素产生影响。异常的细胞极化表明细胞骨架功能障碍，应进一步研究和阐明。正常的fMLP刺激的F - 肌动蛋白聚合反映了甲酰肽信号转导的适当途径。
