Metformin increases basolateral intestinal glucose uptake and utilization (BIGU) in diabetic patients and in obese mice and improves glucose tolerance in these mice. (A) Representative images of whole-body 18F-FDG PET/CT scanning from control individuals (CTL, n = 11) diabetic patients (DM, n = 5) and diabetic patients in use of metformin (DM+MET, n = 16). 18F-FDG PET/CT uptake is color-coded, and areas of increased signal exhibit black color. (B) 18F-FDG biodistribution analysis (SUVmax) in different tissues from CTL, DM and DM+MET diabetic patients. (C) Representative images of whole-body 18F-FDG PET/CT scanning from mice on HFD and treated with vehicle or metformin (MET) with low (50 mg/kg) and high (444 mg/kg) dose for 10 d and 2 h before the PET/CT. 18F-FDG PET/CT uptake is color coded, and areas of increased signal exhibit red-orange color. (D) 18F-FDG biodistribution analysis (SUVmax) in the intestine from mice treated with vehicle (HFD) or treated with metformin (MET) at a low and high dose, respectively. (E) Blood glucose levels from HFD and MET treated mice during a glucose tolerance test (GTT). (F) 18F-FDG biodistribution analysis (SUVmax) in different tissues from HFD and MET mice (50 mg/kg/day for 10 d). All tests performed were one-way ANOVA with Bonferroni’s post-test.