Metabolites secreted by human atherothrombotic aneurysm

One of the possibilities to study abdominal aortic aneurysm (AAA) biomarkers is to use -aneurysm biopsies of dilated arteries or intraluminal thrombus (ILT) for explant cultures. Those metabolites secreted into the culture medium are concentrated in comparison to plasma and free from other interferences that can appear in it, allowing an easier harvesting. Liquid chromatography coupled to quadrupole time-of-flight mass spectrometry detector (LC-QTOF-MS) with an electrospray (ESI) interface has a broad applicability to detect metabolites of all classes with high sensitivity and mass accuracy. Therefore, an LC-QTOF-MS-based metabolomics approach was chosen to select and identify metabolites that could be useful as diagnostic/prognostic markers of AAA. This chapter describes the methodology for the differential analysis of AAA metabolites in secretomes. It gives experimental details on basic steps such as sample preparation, protein precipitation, and analysis of the samples by LC-MS. A description for quality control of the methodology, raw data processing, as well as selection and identification of differentiating -metabolites are also presented in this chapter.