Metabolomic profiling reveals candidate discriminatory metabolites in stable chronic obstructive pulmonary disease and acute exacerbation

To characterize serum metabolic alterations across healthy controls, stable chronic obstructive pulmonary disease (SCOPD), and acute exacerbation of chronic obstructive pulmonary disease (AECOPD), and to explore candidate discriminatory metabolites for COPD-related comparisons. Serum samples from 19 patients with SCOPD, 20 patients with AECOPD, and 20 non-smoking healthy controls were analyzed by LC-MS/MS-based untargeted metabolomics. COPD groups showed reduced glycerophospholipid and alpha-linolenic acid metabolism compared with controls, whereas AECOPD showed enrichment of unsaturated fatty acid biosynthesis compared with SCOPD. PE(16:1(5Z)/16:1(5Z)) and 14,15-leukotriene C4 showed exploratory discriminatory potential in COPD-versus-control and AECOPD-versus-SCOPD comparisons, respectively. Because the study was small and lacked external validation, these metabolites should be interpreted as hypothesis-generating candidates requiring targeted validation.