There is an urgent need to implement holistic and untargeted doping control protocols with improved discriminatory power, compared to conventional methods that only target doping agents. Metabolomics, which aims to characterize all metabolites present in biological matrices, could fulfill this need. In this context, the aim of this study was to evaluate the impact of environmental factors on the ability to obtain a metabolic signature of stanozolol administration in horse doping situation. Urine samples from 16 horses breeded in two different places were collected over a one-year period, before, during and seven months after the administration of stanozolol, a horse doping agent. Metabolomic analysis was performed using ultra-high pressure reverse phase liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (MS). Results showed a major impact of the nutritional regimen, drug administration (for de-worming purpose) and breeding place on the metabolite profiles of horse urines, which hampered the detection of metabolic perturbations induced by stanozolol administration. After having used MS/MS experiments to characterize some MS features related to these environmental factors, we showed that highlighting and then removing the features impacted by these confounding factors before performing supervised multivariate statistical analyses could address this issue. In conclusion, adequate consideration should be given to environmental and physiological factors; otherwise, they can emerge as confounding factors and conceal doping administration.

中文翻译：

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使用液相色谱-高分辨率质谱法对马尿进行代谢组学分析，追踪掩盖轻微甾体掺杂效应的主要环境因素

与仅针对兴奋剂的传统方法相比，迫切需要实施具有改进的歧视能力的整体和非靶向兴奋剂控制协议。代谢组学旨在表征生物基质中存在的所有代谢物，可以满足这一需求。在这种情况下，本研究的目的是评估环境因素对在马兴奋剂情况下获得康力龙给药代谢特征的能力的影响。在一年的时间里，在服用康力龙（一种马兴奋剂）之前、期间和之后七个月的时间里，收集了来自两个不同地方饲养的 16 匹马的尿液样本。使用超高压反相液相色谱与四极杆飞行时间质谱 (MS) 联用进行代谢组学分析。结果表明，营养方案、药物管理（用于驱虫目的）和繁殖地点对马尿的代谢物谱有重大影响，这阻碍了对康力龙给药引起的代谢扰动的检测。在使用 MS/MS 实验表征与这些环境因素相关的一些 MS 特征后，我们表明，在执行有监督的多变量统计分析之前，突出显示然后去除受这些混杂因素影响的特征可以解决这个问题。总之，应充分考虑环境和生理因素；否则，它们可能会成为混杂因素并掩盖兴奋剂管理。药物管理（用于驱虫目的）和马尿代谢物谱上的繁殖地，这阻碍了对康力龙给药引起的代谢扰动的检测。在使用 MS/MS 实验表征与这些环境因素相关的一些 MS 特征后，我们表明，在执行有监督的多变量统计分析之前，突出显示然后去除受这些混杂因素影响的特征可以解决这个问题。总之，应充分考虑环境和生理因素；否则，它们可能会成为混杂因素并掩盖兴奋剂管理。药物管理（用于驱虫目的）和马尿代谢物谱上的繁殖地，这阻碍了对康力龙给药引起的代谢扰动的检测。在使用 MS/MS 实验表征与这些环境因素相关的一些 MS 特征后，我们表明，在执行有监督的多变量统计分析之前，突出显示然后去除受这些混杂因素影响的特征可以解决这个问题。总之，应充分考虑环境和生理因素；否则，它们可能会成为混杂因素并掩盖兴奋剂管理。在使用 MS/MS 实验表征与这些环境因素相关的一些 MS 特征后，我们表明，在执行有监督的多变量统计分析之前，突出显示然后去除受这些混杂因素影响的特征可以解决这个问题。总之，应充分考虑环境和生理因素；否则，它们可能会成为混杂因素并掩盖兴奋剂管理。在使用 MS/MS 实验表征与这些环境因素相关的一些 MS 特征后，我们表明，在执行有监督的多变量统计分析之前，突出显示然后去除受这些混杂因素影响的特征可以解决这个问题。总之，应充分考虑环境和生理因素；否则，它们可能会成为混杂因素并掩盖兴奋剂管理。