GCG and Hyperglycemia: Oxidative stress affects, in fact, insulin signaling cascade, leading to insulin resistance3 and cumulative hyperglycemia and resultant AGE-induced ROS generation16 might impair the incretins' effects via elevation of circulating DPP-4 concentration.4 Of note, we found that, compared with control, post-prandial ox-LDL increase was almost blunted by EVOO and paralleled DPP-4 activity changes with a direct correlation between these two variables, reinforcing the concept that oxidative stress upregulates DPP-4 activity4 and eventually inhibits insulin secretion.