What is true regarding the role of incretin hormones in type 2 diabetes mellitus?

Incretin hormones, which include glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), play a significant role in glucose metabolism, particularly in the regulation of insulin secretion. In a healthy individual, these hormones are released in response to food intake, leading to increased insulin secretion by the pancreas and a decrease in glucagon release. This helps to lower blood glucose levels after meals.

In the context of type 2 diabetes mellitus (T2DM), the action of incretins is diminished. This decreased efficacy is a crucial factor in the pathophysiology of T2DM. Individuals with T2DM often have an impaired incretin effect due to several factors, including insulin resistance and reduced β-cell function, which leads to a suboptimal insulin response to incretin stimulation. As a result, the expected enhancement of insulin secretion that would normally occur with incretin signaling is blunted.

Understanding the role of incretins in T2DM provides insight into therapeutic approaches. Incretin-based therapies, such as GLP-1 receptor agonists and DPP-4 inhibitors, aim to amplify the effects of these hormones, enhancing insulin secretion and improving glycemic control. However, the