Quantification and evaluation of plasma free amino acid concentrations by LC-MS/MS after total gastrectomy

The effect of total gastrectomy (TG) on plasma free amino acid (PFAA) concentrations in patients with stage II gastric cancer was investigated in the study. Nineteen patients' plasma samples were collected before and three months post-gastrectomy, and PFAA levels were quantified using LC-MS/MS. For gradient elution of amino acids, the mobile phases (A: 3% formic acid-5% methanol-30 mM ammonium formate, B: acetonitrile) and a Hypersil C18 column (100 mm x 2.1 m, 1.9 µm) were used. The findings revealed substantial modifications in the profile of PFAA after TG. In particular, the concentrations of twenty amino acids increased significantly, including branched-chain amino acids, L-glutamate, L-alanine, L-methionine, glycine, L-cystine, and L-histidine. Conversely, L-arginine was also reduced statistically. These alterations in the PFAA profile indicate the favorable effects of TG on various physiological processes, such as enhanced immune function, improved tissue healing, and increased energy production. Investigating the effects of various surgical techniques on PFAA profiles is a promising approach for optimizing surgical procedures, improving metabolic function, increasing immunological responses, and improving overall quality of life. These findings highlight the significance of evaluating amino acid metabolism as an important part of treatment, given its potential to improve clinical outcomes and general well-being.