The Role of Incretins (GLP-1 and GIP) in glucose control.^2,5,8-10,13

Overview| Incretin response| β-cell stimulation| Suppression of glucagon from α-cells

GLP-1 and GIP are the two major incretin hormones found in man.^1,2 These incretins are released from the gut in response to ingestion of food⁵ and collectively contribute to glucose control by:

• Stimulating glucose-dependent insulin release from pancreatic beta cells (GLP-1 and GIP)²;
  • insulin increases glucose uptake in peripheral tissues (mainly muscle and fat) and
  • suppresses glucose production from the liver^9,10
• Decreasing glucagon production from pancreatic alpha cells (GLP-1)^10,13 when glucose levels are elevated.

The combination of increased insulin and decreased glucagon reduces hepatic glucose production when plasma glucose is elevated.²