Amino Acid Metabolite Profiling for Predicting and Understanding the Metabolic Effects of Metabolic and Bariatric Surgery.

Metabolic and bariatric surgery induces metabolic benefits beyond weight loss, including improved insulin sensitivity, type 2 diabetes (T2D) remission, and reduced inflammation. Recent metabolomics research highlights amino acid metabolites-branched-chain amino acids, aromatic amino acids, and tryptophan-derived compounds-as key biomarkers for predicting surgical outcomes. Elevated preoperative levels of isoleucine, phenylalanine, levodopa, and 3-hydroxyanthranilic acid are associated with improved glycemic control and T2D remission. Gut microbiota-derived metabolites, including indole-3-propionic acid and indole-3-pyruvic acid, contribute to insulin sensitivity and lean mass preservation. Additionally, serotonin-related indicators predict postoperative weight loss rates. These metabolites reflect individual metabolic heterogeneity and may outperform conventional clinical models in predicting surgical responsiveness. Integration of metabolomics into preoperative assessment may enhance precision medicine approaches and identify new therapeutic targets.