What is the difference between GLP-1 and GIP?

GIP acts directly on the endocrine pancreas, bone, fat, gastrointestinal (GI) tract and brain. GLP‐1 acts directly on the endocrine pancreas, gastrointestinal tract, heart and brain.

What is the incretin effect of GLP-1 and GIP?

The term incretin effect was used to describe the fact that oral glucose load produces a greater insulin response than that of an isoglycemic intravenous glucose infusion. This difference has been attributed to gastrointestinal peptides GLP-1 and GIP.

How is GLP-1 degraded?

Intact GLP-1 and GIP are inactivated during passage across the hepatic bed by DPP IV associated with the hepatocytes, and further degraded by the peripheral tissues, while the kidney is important for the final elimination of the metabolites.

Where is GLP-1 primarily degraded?

It is widely accepted that the intact forms of the incretin hormones, GLP-1(7–36) amide and GIP(1–42), are degraded primarily by the ubiquitous enzyme dipeptidyl peptidase 4 (DPP-4) (3–5) and to a minor extent by various neutral endopeptidases (NEPs) and additional aminopeptidases (6–8).

How does GIP stimulate insulin secretion?

GIP directly stimulates insulin secretion through the β cell GIPR. Indirectly, GIP potentiates α cell activity to enhance α to β cell communication through the GLP-1R/GCGR. Thus, GIP indirectly stimulates insulin secretion through the α cell.

How is glucagon degraded?

Other degradative processes include oxidation at Met residues, a process to which glucagon is susceptible [21]. Joshi and Kirsch extensively studied the mechanisms of glucagon degradation at acid pH and found that deamidation was caused by direct hydrolysis of the amide side-chain by water [19].

What is the half life of GLP-1?

Native GLP-1 has a very short half-life (about 2 minutes) because of rapid degradation by the endogenous enzymes dipeptidyl-peptidase-IV (DPP-4)67) and neutral endopeptidase (NEP)68).

Which enzyme is responsible for GLP-1 inactivation?

GLP-1 is extremely rapidly metabolized and inactivated by the enzyme dipeptidyl peptidase IV even before the hormone has left the gut, raising the possibility that the actions of GLP-1 are transmitted via sensory neurons in the intestine and the liver expressing the GLP-1 receptor.

Which class of drugs increases GLP-1 and GIP which increases pancreatic insulin secretion and decreases glucagon secretion?

The incretin mimetics currently being used are GLP-1 receptor agonists. They work by activating the GLP-1 receptors, which increases insulin secretion, decreases glucagon secretion, slows or delays gastric emptying, and increases satiety.

What does GIP do insulin?

Gastric inhibitory polypeptide (GIP), or gastric inhibitory peptide, also known as glucose-dependent insulinotropic polypeptide (also abbreviated as GIP), is an inhibiting hormone of the secretin family of hormones. While it is a weak inhibitor of gastric acid secretion, its main role is to stimulate insulin secretion.

Does GIP inhibit food intake?

Another important difference is that GLP-1 inhibits appetite and food intake (5), resulting in weight loss upon chronic administration, whereas GIP generally is thought to have no effects on food intake (6).