Department of Chemistry and Applied Biosciences, Federal Institute of Technology , Zurich, Switzerland.
Division of Respiratory Medicine, University Children's Hospital Zurich and Children's Research Center Zurich , Zurich, Switzerland.
Anal Chem. 2017 Oct 3;89(19):10329-10334. doi: 10.1021/acs.analchem.7b02092. Epub 2017 Sep 14.
Omega-oxidation is a fatty acid degradation pathway that can occur alternatively to the dominant β-oxidation. The dysregulation of fatty acid oxidation has been related with a variety of diseases, termed fatty acid oxidation disorders. This work shows evidence for real-time detection in exhaled breath of the complete series of saturated linear ω-hydroxyalkanoic acids, ω-oxoalkanoic acids, and alkanedioic acids with carbon chain lengths of 5-15. We present a comprehensive analytical workflow using online and subsequent offline methods: secondary electrospray ionization mass spectrometry of exhaled breath and UHPLC-HRMS/MS experiments using exhaled breath condensate, respectively. By analyzing online breath measurements of 146 healthy individuals, we were able to obtain strong evidence for the correlation of these metabolite families. This enabled us to monitor the full ω-oxidation pathway in human exhaled breath. We could unambiguously identify these compounds, many of which have never been reported in breath so far. This comprehensive study on breath metabolites reinforces the notion of breath as a valuable source of information, which is underexploited in metabolomics.
ω-氧化是脂肪酸降解途径之一，可替代占主导地位的β-氧化发生。脂肪酸氧化的失调与多种疾病有关，这些疾病被称为脂肪酸氧化紊乱。本工作证明了实时检测呼气中具有 5-15 个碳原子链长的饱和直链ω-羟基烷酸、ω-氧代烷酸和烷二羧酸的完整系列的可能性。我们提出了一种综合的分析工作流程，使用在线和随后的离线方法：呼气中次级电喷雾电离质谱和使用呼气冷凝物的 UHPLC-HRMS/MS 实验。通过分析 146 名健康个体的在线呼气测量，我们能够获得这些代谢物家族相关性的有力证据。这使我们能够监测人体呼气中的完整ω-氧化途径。我们能够明确地识别这些化合物，其中许多化合物迄今为止从未在呼气中报道过。这项关于呼气代谢物的综合研究加强了呼气作为一种有价值的信息来源的概念，而代谢组学对其的利用还远远不够。
