A Comparative Metabolomics Study of Multiple Urological Diseases by Highly Sensitive Dansylation Isotope Labeling LC-MS

Urine analysis is a straightforward, non-invasive testing method that, when integrated with metabolomics, shows great potential for detecting small-molecule metabolites as biomarkers of abnormal metabolic activity in the urinary tract, including drug interactions, toxicity, and diseases. However, integrated and comparative analyses of multiple urinary tract pathologies are currently limited. In this study, ¹²C2/¹³C2-chemical dansylation labeling was used to explore the urinary amine/phenol-metabolome profiles of eight urological conditions compared with normal profiles. We obtained ten samples for each condition (disease and normal) from a total of 90 participants, pooling them as representative samples, and constructed metabolite panels to differentiate various urological conditions. We discovered nine metabolites that were dysregulated between urine samples from patients with and without cancer. Another seven metabolites were differentially expressed between the benign prostatic hyperplasia group and the prostate cancer group. Among 1854 peak pairs of metabolites in an amine/phenol submetabolome analyzed by dansyl chloride derivatization coupled with LC-MS/MS, 1747 (94.2%) were detectable in urine specimens from all nine groups. Notably, 18 identified metabolites showed substantial stability across all urological conditions. Given the considerable variability in urine metabolite composition, these metabolites could potentially be used for normalization in urine metabolome analysis, addressing the need for stably expressed molecules as internal standards in the development of urinary biomarkers. Our findings provide the preliminary insights into the stability of urinary metabolomics and the metabolic perturbations associated with different urinary tract-related pathologies.