Systemic metabolic alterations in Ménière's disease: Insights from urinary 1H NMR-based metabolomics.

Ménière's disease (MD) is a chronic inner ear syndrome characterized by vertigo, tinnitus, and fluctuating sensorineural hearing loss. Despite its well-defined clinical presentation, the underlying pathophysiology remains elusive, often resulting in empirical and partially effective treatments. This multicenter pilot study employed 1H NMR-based urinary metabolomics to identify metabolic pathways and potential diagnostic biomarkers related to the disease. The study analyzed 50 urine samples (30 MD patients, 20 controls), identifying 109 metabolites from both endogenous and exogenous sources. While principal-component analysis (PCA) confirmed no center-based clusterization, univariate analysis (volcano plot) revealed four significantly downregulated signals in the MD cohort: threonine/lactate, 2-hydroxyisobutyrate, dimethyl sulfone/ethanolamine, and tyrosine/tyramine. These metabolic alterations suggest systemic dysregulation in energy metabolism, inflammation, and neurotransmitter pathways in MD. Our findings support the potential of urinary NMR-based metabolomics in identifying promising diagnostic biomarkers as well as elucidating the pathophysiology of MD.