Conventional anti-hyperglycemic drugs exhibit inadequate efficacy, a short duration of activity, and side effects such as hypoglycemia, weight gain, and digestive symptoms.
Therefore, these drugs are associated with problems regarding safety and tolerability. In 2006, the US Food and Drug Administration approved the dipeptidyl peptidase-4 (DPP-4) inhibitor sitagliptin. DPP-4 inhibitors are a new class of anti-diabetic drugs that exhibit different mechanisms of action from conventional anti-diabetic drugs.1
They inhance the body’s own ability to lower blood glucose when it is elevated. This action of …show more content…
However, the effects of GLP-1 and GIP last only for a few minutes as they are inactivated due to DPP-4 (Thornberry and Gallwitz 2009).4
Their rapid degradation by the DPP IV enzyme, limits their duration of action.The development of DPP-4-resistant GLP-1 analogues (incretin mimetics) and DPP- 4 inhibitors (incretin enhancers) were logically proposed as an alternative means of exploiting the full therapeutic potential of this “incretin effect”.
The inhibitors of the DPP-4 enzyme, which rapidly degrades the two major gastrointestinal hormones into inactive products, the “gliptins” increase the levels of the incretin hormones GLP-1 and GIP. The pharmacology of these drugs is based on very sound principles and this is why the gliptins are considered such attractive molecules for clinical use.5
Patients with type 2 diabetes tend to have low incretin levels postprandially.6
Studies have shown that an improvement in glycemia can be achieved by increasing circulating GLP-1 via an infusion of native GLP-1. Unfortunately, native GLP-1 has an extremely short half-life in the circulation and, being a peptide hormone, needs to be given by continuous intravenous infusion in order to maintain normal physiologic