High throughput mass spectrometry (MS)-based metabolomics is a popular platform for small molecule metabolites analyses that are widely used for detecting biomarkers in the research field of environmental assessment. Crucian carp (Carassius carassius, CC) is an economically and ecologically important fish in Asia. It can adapt to extremely high alkalinity, providing us with valuable material to understand the adaptation mechanism for extreme environmental stress. However, the information on the metabolite biomarkers and metabolic mechanisms of CC exposed to alkaline stress is not entirely clear. We applied high-throughput UPLC-Q-TOF/MS combined with chemometrics to identify changes in the metabolome of CC exposed to different concentrations of alkalinity for long term effects. Metabolic differences among alkalinity-treated groups were identified by multivariate statistical analysis. Further, 7 differential metabolites were found after exposure to alkaline conditions. In total, 23 metabolic pathways of these differential metabolites were significantly affected. Alkalinity exposure resulted in widespread change in metabolic profiles in the plasma with disruptions in the phenylalanine metabolism, glycine, serine and threonine metabolism, pyruvate metabolism, tyrosine metabolism, etc. The integrated pathway analysis of the associated metabolites showed that tRNA charging, L-cysteine degradation II, superpathway of methionine degradation, L-serine degradation, tyrosine biosynthesis IV, etc. appear to be the most significantly represented functional categories. Overall, this study demonstrated that metabolic changes in CC played a role in adaptation to the highly alkaline environmental stress.

中文翻译：

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高通量代谢组学有助于发现鱼类对碱度胁迫的代谢物生物标志物和代谢机制†

基于高通量质谱 (MS) 的代谢组学是一种流行的小分子代谢物分析平台，广泛用于检测环境评估研究领域的生物标志物。鲫鱼 ( Carassius carassius, CC) 是亚洲重要的经济和生态鱼类。它可以适应极高的碱度，为我们了解极端环境压力的适应机制提供了宝贵的材料。然而，关于 CC 暴露于碱性胁迫的代谢物生物标志物和代谢机制的信息并不完全清楚。我们应用高通量 UPLC-Q-TOF/MS 与化学计量学相结合，以确定长期影响不同浓度碱度的 CC 代谢组的变化。通过多变量统计分析确定碱度处理组之间的代谢差异。此外，在暴露于碱性条件后发现了 7 种差异代谢物。总的来说，这些差异代谢物的 23 条代谢途径受到了显着影响。相关代谢物的综合通路分析表明，tRNA充电、L-半胱氨酸降解II、蛋氨酸降解超通路、L-丝氨酸降解、酪氨酸生物合成IV等似乎是最具代表性的功能类别。总体而言，这项研究表明，CC 的代谢变化在适应高碱性环境压力方面发挥了作用。