[Research progress of mechanisms through which dipeptidyl peptidase-4 inhibitors regulate glycemia].

Dipeptidyl peptidase-4 (DPP-4) inhibitors are promising new antidiabetic drugs. It had been proposed that DPP-4 inhibitors exert their antidiabetic effect by inhibiting the degradation of glucagon-like peptide 1(GLP-1) . However, new evidence has shown that the increase of GLP-1 is not notable after the use of these drugs in patients with type 2 diabetes. Therefore, the specific mechanisms via which DPP-4 inhibitors in controlling blood glucose has became questionable. In recent years, studies have revealed many possible mechanisms through which DPP-4 inhibitors regulate glycemia: DPP-4 inhibitors may selectively reduce DPP-4 activity in the intestine, causing the increase of portal plasma GLP-1 level and thus promoting the release of insulin via nerve reflex;also, they may decrease the cleavage product of GLP-1 and reduce the degradation of other bioactive peptides.