Metabolic regulation of amino acids provides an important basis for individualized nutritional therapy for patients with gastric cancer during the perioperative period.

[BACKGROUND] Gastric cancer is a prevalent malignancy worldwide, with early detection and treatment being vital to improving patient outcomes. Amino acids (AAs), as essential regulators in cancer cell metabolism, are implicated in the progression and response to treatment.

[METHODS] This study aimed to investigate the dynamics of plasma AA levels in gastric cancer patients preoperatively, postoperatively, and following nutritional intervention, comparing them to healthy controls. We analyzed 22 AAs in plasma samples from 66 gastric cancer patients and 55 healthy individuals.

[RESULTS] The results show that significant preoperative elevation of AAs, such as threonine (Thr), serine (Ser), proline (Pro), lysine (Lys), arginine (Arg), citrulline (Cit), glutamine (Gln), glycine(Gly), and alanine (Ala), with reductions in taurine (Tau), phenylalanine (Phe) and hydroxylysine (Hylys). Post-surgery, levels of many AAs decreased markedly, but were partially restored following nutritional intervention, with some exceeding preoperative values. Nevertheless, specific AAs, including methionine (Met) and Gln, remained lower than in healthy controls, suggesting potential benefit from targeted supplementation. Correlations between AA changes and postoperative recovery indicators were observed; notably, increased postoperative Thr, Ser, Tau, tyrosine (Tyr), glutamic acid (Glu), and Hylys levels were associated with quicker gastrointestinal recovery. Additionally, several AAs, such as Pro, Lys, Tyr, Met, Cit, and Glu, were linked to reduced inflammation, as reflected by C-reactive protein (CRP) and white blood cell (WBC) levels, suggesting roles in the postoperative immune response. Pathway enrichment analysis highlighted metabolic pathways involving Gly, Ser, Phe, Tyr, Lys, and Met as critical in the recovery process.

[CONCLUSIONS] These findings underscore the potential of AA profiles as biomarkers for postoperative recovery and suggest nutritional interventions targeting specific AAs may improve outcomes.