Enders Kira, Hillen Barlo, Haller Nils, Brahmer Alexandra, Weber Vincent, Simon Perikles, Neuberger Elmo W I
Department of Sports Medicine, Disease Prevention and Rehabilitation, Johannes Gutenberg University Mainz, Mainz, Germany.
Department of Sport and Exercise Science, University of Salzburg, Salzburg, Austria.
Exp Physiol. 2025 Mar 3. doi: 10.1113/EP092284.
Circulating cell-free DNA (cfDNA) is a promising biomarker for physiological stress, including exercise-induced responses. However, the lack of standardization in blood collection tubes (BCTs) for quantification of cfDNA hampers inter-study comparisons. In this study, we assessed the impact of different BCTs on exercise-induced cfDNA dynamics. Eleven participants [25 (SD 2.3) years of age] performed three different treadmill exercise protocols, including an all-out test and combinations of constant and interval load. Blood samples were collected before, 5 min and 30 min post-exercise using EDTA, lithium-heparin (LH) and serum BCTs. Concentrations of cfDNA were quantified using quantitative PCR. The cfDNA increased significantly across all protocols and BCTs. A significant effect of BCT on cfDNA concentrations (P = 0.034) was found, with serum showing higher concentrations than EDTA and LH. Although absolute differences from pre- to post-exercise were comparable across BCTs (P = 0.476), fold changes differed significantly (P = 0.012), with the highest observed in EDTA and the lowest in serum. Bland-Altman analyses demonstrated better agreement between EDTA and LH compared with serum. Significant correlations of cfDNA with energy expenditure and peak oxygen uptake were found. These correlations were stronger in EDTA and LH than in serum. Our findings highlight the crucial influence of BCT choice on cfDNA measurements in exercise settings. Given that EDTA and LH reflected exercise load better, they could be preferred for exercise physiology research. This work underscores the need to account for the choice of BCT to improve data comparability across studies. Additionally, these findings might have broader implications for clinical settings where cfDNA is used as a biomarker.
循环游离DNA（cfDNA）是一种很有前景的生理应激生物标志物，包括运动诱导的反应。然而，用于cfDNA定量的血液采集管（BCT）缺乏标准化阻碍了研究间的比较。在本研究中，我们评估了不同BCT对运动诱导的cfDNA动态变化的影响。11名参与者[年龄25（标准差2.3）岁]进行了三种不同的跑步机运动方案，包括全力测试以及恒定负荷和间歇负荷的组合。在运动前、运动后5分钟和30分钟使用乙二胺四乙酸（EDTA）、锂肝素（LH）和血清BCT采集血样。使用定量聚合酶链反应对cfDNA浓度进行定量。在所有方案和BCT中，cfDNA均显著增加。发现BCT对cfDNA浓度有显著影响（P = 0.034），血清显示的浓度高于EDTA和LH。尽管不同BCT从运动前到运动后的绝对差异具有可比性（P = 0.476），但倍数变化差异显著（P = 0.012），其中EDTA中观察到的倍数变化最高，血清中最低。布兰德-奥特曼分析表明，与血清相比，EDTA和LH之间的一致性更好。发现cfDNA与能量消耗和峰值摄氧量存在显著相关性。这些相关性在EDTA和LH中比在血清中更强。我们的研究结果突出了BCT选择对运动环境中cfDNA测量的关键影响。鉴于EDTA和LH能更好地反映运动负荷，它们可能更适合用于运动生理学研究。这项工作强调了考虑BCT选择以提高研究间数据可比性的必要性。此外，这些发现可能对将cfDNA用作生物标志物的临床环境具有更广泛的意义。
