Drug Analysis Department, Laboratory of Racing Chemistry, Utsunomiya, Japan.
Bioinformatics Team, Research Laboratory, H. U. Group Research Institute G.K., Hachioji, Japan.
Drug Test Anal. 2022 May;14(5):915-928. doi: 10.1002/dta.3041. Epub 2021 May 17.
In the context of doping control, conventional direct chemical testing detects only a limited scope of target substances in equine biological samples. To expand the ability to detect doping agents and their detection windows, metabolomics has recently become a common approach for monitoring alteration of biomarkers caused by doping agents in relevant metabolic pathways. In horse racing, remarkable changes in metabolic profiles between the rest state and racing are likely to affect the identification of doping biomarkers. Previously, we reported a limited number of significantly upregulated metabolites after racing, based on a non-targeted metabolomics approach using out-of-competition and post-race equine plasma samples. In this study, we performed a more thorough analysis of the data set, using pathway analysis to establish a post-race biomarkers database (PBD) that includes upregulated and downregulated metabolites, their fold changes, and relevant pathways, with the main objective of improving our understanding of changes in physiological status related to horse racing. Statistical analysis of the PBD revealed that two peak combinations of pentadecanoyl carnitine/galactosylglycerol (P/G) and heptadecanoyl carnitine/galactosylglycerol (H/G) could be used as potential biomarkers for the discrimination of the rest and post-race groups. To demonstrate the applicability of the PBD, we validated the post-race biomarkers P/G and H/G (highly involved in lipid metabolism) by a single-blind test. This strategy, which combines establishment of a biomarker database with pathway analysis, represents a powerful tool for discovering potential doping biomarkers in the future.
在兴奋剂检测方面，传统的直接化学检测方法只能检测马属动物生物样本中有限数量的目标物质。为了扩大检测兴奋剂及其检测窗口期的能力，代谢组学已成为监测兴奋剂相关代谢途径中生物标志物变化的常用方法。在赛马中，休息状态和比赛状态之间代谢谱的显著变化可能会影响兴奋剂生物标志物的识别。此前，我们基于非靶向代谢组学方法，使用比赛外和赛后马属动物血浆样本，报道了比赛后少数几个显著上调的代谢物。在这项研究中，我们使用途径分析对数据集进行了更深入的分析，建立了一个包含上调和下调代谢物、它们的倍数变化以及相关途径的赛后生物标志物数据库（PBD），主要目的是提高我们对与赛马相关的生理状态变化的理解。对 PBD 的统计分析显示，十五烷酰肉碱/半乳糖甘油（P/G）和十七烷酰肉碱/半乳糖甘油（H/G）的两个峰组合可用于区分休息和赛后组。为了验证 PBD 的适用性，我们通过单盲测试对赛后生物标志物 P/G 和 H/G（高度参与脂代谢）进行了验证。这种结合生物标志物数据库建立和途径分析的策略，代表了未来发现潜在兴奋剂生物标志物的有力工具。
