What is the mechanism of action of Sitagliptin?

Sitagliptin works by inhibiting the enzyme DPP-4 (dipeptidyl peptidase-4). This enzyme is responsible for breaking down incretin hormones, which are involved in the regulation of glucose metabolism. By inhibiting DPP-4, Sitagliptin prolongs the action of these incretin hormones, leading to enhanced insulin secretion in response to meals and decreased glucagon release from the pancreas. This results in better control of blood glucose levels in individuals with type 2 diabetes.

The action of Sitagliptin does not directly increase blood glucose levels; instead, it leads to an overall reduction in blood glucose by improving insulin response and suppressing glucagon levels. This is why its mechanism is significant for managing diabetes effectively. Understanding the role of DPP-4 in glucose regulation helps clarify why Sitagliptin is used as a therapeutic agent for lowering blood sugar.