Diet-Induced Adipose Tissue Inflammation and Liver Steatosis Are Prevented by DPP-4 Inhibition in Diabetic Mice

OBJECTIVE—Diet composition alters the metabolic states of adipocytes and hepatocytes in diabetes. The effects of dipeptidyl peptidase-4 (DPP-4) inhibition on adipose tissue inflammation and fatty liver have been obscure. We investigated the extrap-ancreatic effects of DPP-4 inhibition on visceral fat and the liver. RESEARCH DESIGN AND METHODS—We investigated diet-induced metabolic changes in b-cell–specific glucokinase hap-loinsufficient (Gck+/2) diabetic mice. We challenged animals with a diet containing a combination of sucrose and oleic acid (SO) or sucrose and linoleic acid (SL). Next, we assessed the effects of a DPP-4 inhibitor, des-fluoro-sitagliptin, on adipose tissue inflam-mation and hepatic steatosis. RESULTS—The epididymal fat weight and serum leptin level were significantly higher in Gck+/2 mice fed SL than in mice fed SO, although no significant differences in body weight or adipo