Analysis of serum metabolite profiles in syphilis patients by untargeted metabolomics.

BACKGROUND:Global metabolomics analysis can provide substantial information on energy metabolism, physiology, possible diagnostic biomarkers and intervention strategies for pathogens. OBJECTIVE:To gain a better understanding of the mechanisms of syphilis and analysis of serum metabolite profiles in syphilis patients. METHODS:We conducted an untargeted metabolomics analysis of serum from 20 syphilis patients and 20 healthy controls. RESULTS:A total of 2890 molecular features were extracted from each sample, and the peak intensity of each feature was obtained. Distinct differential metabolites were identified by principal component analysis, partial least squares-discriminant analysis and hierarchical clustering analysis. Furthermore, five metabolites were identified as significantly different by Student's t-test, including trimethylamine N-oxide, l-arginine, lysoPC(18:0), betaine and acetylcarnitine. KEGG analysis showed that these differential metabolites were in various pathways, including Chagas disease, fatty acid biosynthesis, primary bile acid biosynthesis, Salmonella infection, ABC transporters, glycerophospholipid metabolism and choline metabolism. Among them, trimethylamine N-oxide was 3.922 times in patients with syphilis than healthy controls. CONCLUSION:Trimethylamine N-oxide may be used as an indicator to distinguish between syphilis patients and healthy controls. The changes in these metabolites suggest that Treponema pallidum affects the normal metabolic activity of host cells, providing some clues for elucidating the pathogenesis of T. pallidum.