The Relationship between Anagliptin Concentration Showing Over 80% Inhibition of Plasma Dipeptidyl Peptidase-4 Activity and its Protective Effect against Glucagon-like Peptide-1 Degradation

In dipeptidyl peptidase-4 (DPP-4) inhibitors, the inhibition of plasma DPP-4 activity by 80% is considered sufficient to have an effect on glycemic control improvement through the elevation of intact glucagon-like peptide-1 (GLP-1). To clarify whether or not the 80% inhibition is sufficient to protect against GLP-1 degradation, we investigated rats with a continuous infusion of exogenous GLP-1. When GLP-1 was infused into the femoral or portal vein, the steady state active GLP-1 levels in plasma significantly increased (P