Changes in Glucose Metabolism in Vertical Sleeve Gastrectomy

We evaluated metabolic changes after vertical sleeve gastrectomy (VSG) surgery in a rat model using proteomics and metabolomic profiling in liver and serum. Rats were randomly divided into two groups: sham (n = 10) and VSG (n = 12). Food intake, body weight, blood glucose, insulin, and thyroid hormone levels were measured. Two-dimensional electrophoresis, nuclear resonance spectroscopy, mass spectroscopy, immunofluorescence, and immunoblot analyses were used to determine and validate changes in metabolites and proteins in liver tissue and serum samples. Food intake and body weight decreased after VSG group (p < 0.05 and p < 0.05, respectively). Random blood glucose (sham, 183.3 +/- 5.6 mg/dL; VSG, 138.5 +/- 3.7 mg/dL) decreased while random insulin (sham, 0.45 +/- 0.16 mu g/L; VSG, 1.05 +/- 0.18 mu g/L) increased after VSG (p < 0.05 and p < 0.01, respectively). We found that expressions of gluconeogenic enzymes (phosphoenolpyruvate carboxykinase-1 and glucose-6-phosphatase) and concentrations of pyruvate and malate decreased while lactate, NADH, NADPH, glucose, and AMP/ATP ratio increased after VSG. Thyroid hormones, triiodothyronine (T3) and free thyroxine (fT4), decreased after VSG. This study proves that VSG suppresses hepatic glucose production.