Glucagon-Like Peptide-1 (GLP-1)

Definition

Glucagon-like peptide-1 (GLP-1) is an incretin hormone produced by intestinal L cells that plays a crucial role in regulating glucose homeostasis and insulin secretion. It is a key component of the endocrine pancreas and its functions are closely tied to the maintenance of normal blood sugar levels.

5 Must Know Facts For Your Next Test

1. GLP-1 is secreted by intestinal L cells in response to the presence of nutrients in the gut, particularly carbohydrates and fats.
2. GLP-1 stimulates the pancreatic beta cells to increase insulin secretion, promoting glucose uptake by cells and lowering blood glucose levels.
3. GLP-1 also inhibits glucagon secretion from the pancreatic alpha cells, further contributing to the reduction of blood glucose.
4. GLP-1 slows gastric emptying and promotes satiety, which can lead to reduced food intake and weight loss.
5. Impaired GLP-1 secretion or action is associated with the development of type 2 diabetes, making it a target for therapeutic interventions.

Review Questions

• Explain the role of GLP-1 in glucose homeostasis and insulin secretion.
  • GLP-1 plays a crucial role in glucose homeostasis by stimulating insulin secretion from pancreatic beta cells in response to elevated blood glucose levels. This insulin secretion promotes the uptake of glucose by cells, lowering blood sugar. Additionally, GLP-1 inhibits glucagon secretion from pancreatic alpha cells, further contributing to the reduction of blood glucose levels. The actions of GLP-1 on insulin and glucagon secretion are essential for maintaining normal blood sugar regulation.
• Describe the relationship between GLP-1 and the development of type 2 diabetes.
  • Impaired GLP-1 secretion or action is associated with the development of type 2 diabetes. In individuals with type 2 diabetes, the body's sensitivity to GLP-1 may be reduced, leading to decreased insulin secretion and impaired glucose homeostasis. This can contribute to the progression of the disease. As a result, GLP-1 and its signaling pathways have become a target for therapeutic interventions in the management of type 2 diabetes, with the development of GLP-1 receptor agonists and DPP-4 inhibitors to enhance GLP-1 action and improve glycemic control.
• Analyze the broader physiological effects of GLP-1 beyond its role in glucose regulation.
  • In addition to its primary function in glucose homeostasis, GLP-1 has broader physiological effects that contribute to overall metabolic regulation. GLP-1 has been shown to slow gastric emptying, which can lead to a feeling of fullness and reduced food intake, potentially contributing to weight loss. Furthermore, GLP-1 has been found to have neuroprotective effects and may play a role in regulating appetite and satiety signals in the brain. These wider-ranging actions of GLP-1 highlight its importance as a key player in the complex network of hormones and signaling pathways that govern energy balance and metabolic health.

Related terms

Incretin: Incretins are hormones secreted by the gut that stimulate insulin release from the pancreas in response to food intake, helping to control blood glucose levels.

Insulin: Insulin is a hormone produced by the pancreas that allows cells to utilize glucose, lowering blood sugar levels.

Glucose Homeostasis: Glucose homeostasis is the process of maintaining stable blood glucose levels within a normal range through the coordinated action of insulin, glucagon, and other regulatory mechanisms.