Effect of Metformin on Fibroblast Growth Factor-21 Levels in Patients with Newly Diagnosed Type 2 Diabetes

Fibroblast growth factor (FGF)-21 is an important regulator of glucose metabolism. In the present study, we investigated whether plasma levels of FGF-21 changed in patients with newly diagnosed type 2 diabetes mellitus (T2DM) and assessed the effects of metformin treatment on plasma FGF-21 levels. The plasma FGF-21 levels and the metabolic parameters of 226 patients with newly diagnosed T2DM and 100 sex- and age-matched normal glycemic tolerant (NGT) controls were measured. Seventy-four patients among of the 226 patients with T2DM were treated with metformin throughout the 12-week study period. The fasting plasma FGF-21 and high-sensitivity C-reactive protein (hs-CRP) levels were measured using enzyme-linked immunosorbent assay kits. The patients with T2DM had significantly higher fasting plasma FGF-21 levels (302.2 pg/mL [range, 201.3-454.4 pg/mL] vs. 104.5 pg/mL [range, 71.6-185.6 pg/mL]; P