Study on serum metabolomics characteristics of obese patients with erectile dysfunction

Erectile dysfunction (ED) is a common male sexual health problem that can be associated with obesity. This study aimed to identify serum metabolic differences and pathways related to ED in obese men using non-targeted metabolomics techniques. We included 54 obese male patients with (n = 27) and without (n = 27) ED. We collected 5 mL of fasting elbow vein blood and analyzed serum metabolites using ultra-high-performance liquid chromatography-mass spectrometry. Multivariate statistical methods (principal component analysis and orthogonal partial least squares discriminant analysis) were used to identify differential metabolites between the groups. Finally, pathway analysis using the Kyoto encyclopedia of genes and genomes database identified 4 differential metabolic pathways in obese men with ED compared to obese men without ED. A total of 77 differential metabolites were identified in obese men with ED compared to the control group (obese men without ED) using a threshold of variable importance in the projection > 1 and P < .05. Pathway analysis revealed 4 main differences: glycine, serine and threonine metabolism, glycerophospholipid metabolism, aminoacyl-tRNA biosynthesis, and D-glutamine and D-glutamate metabolism. Specific metabolites associated with these pathways included betaine aldehyde, choline, L-threonine, phosphatidylcholine, L-serine, and D-glutamine. Our findings suggest abnormalities in fatty acid metabolism, phospholipid metabolism, and amino acid metabolism between obese men with and without ED. Metabolites such as betaine aldehyde, choline, L-threonine, phosphatidylcholine, L-serine, and D-glutamine may be potential biomarkers for distinguishing obese men with ED.