Metformin mitigated metabolic alterations in obese mice. ND-fed lean and HFD-fed obese mice were subcutaneously inoculated with LLC cells over a course of three weeks. Three days after cell implantation, ND-fed lean mice were treated daily with saline vehicle through intraperitoneal injection (ND). HFD-fed obese mice were separated into two groups receiving daily intraperitoneal injections of a saline vehicle (HFD) or metformin (50 mg/kg, HFD/Metformin) for the final 18 days. Body mass (A), fasting glucose (B), fasting insulin (C), HOMA-IR (D), plasma leptin (E) and plasma glutamine (F) were all determined. * p < 0.05 vs. ND and # p < 0.05 vs. HFD, n = 6.