Metabolomic Profiling Differences among Asthma, COPD, and Healthy Subjects: A LC-MS-based Metabolomic Analysis.

Objective Asthma and chronic obstructive pulmonary disease (COPD) feature different inflammatory and cellular profiles in the airways, indicating that the cellular metabolic pathways regulating these disorders are distinct. Methods We aimed to compare the serum metabolomic profiles among mild persistent asthmatic patients, individuals with stable COPD, and healthy subjects and to explore the potential metabolic biomarkers and pathways. The serum metabolomic profiles of 17 subjects with mild persistent asthma, 17 subjects with stable COPD, and 15 healthy subjects were determined by an untargeted metabolomic analysis utilizing liquid chromatography-mass spectrometry. A series of multivariate statistical analyses was subsequently used. Results Multivariate analysis indicated a distinct separation between the asthmatic patients and healthy controls in electrospray positive and negative ions modes, respectively. A total of 19 differential metabolites were identified. Similarly, a distinct separation between asthma and COPD subjects was detected in the two ions modes. A total of 16 differential metabolites were identified. Among the identified metabolites, the serum levels of hypoxanthine were markedly higher in asthmatic subjects compared with those in COPD or healthy subjects. Conclusions Patients with asthma present a unique serum metabolome, which can distinguish them from individuals with COPD and healthy subjects. Purine metabolism alteration may be distinct and involved in the pathogenesis of asthma.