Even without a pancreas, GLP-1 reduces postprandial glucose excursions by 45%, while GIP suppresses bone resorption by 65% and alters cardiovascular parameters, highlighting their distinct extrapancreatic effects.
Can incretin hormones influence metabolism even when the pancreas—the primary site of their insulin-stimulating action—is absent? Novel research in individuals who have undergone total pancreatectomy suggests that the answer is yes. The findings reveal distinct physiological effects of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), extending beyond pancreatic insulin secretion and yielding insights into incretin biology and pancreatogenic diabetes.
In this randomized study, researchers evaluated 12 subjects following total pancreatectomy (five women; mean age, 58.8 ± 13.9 years; mean body mass index [BMI], 24.7 ± 5.1 kg/m²). Each subject underwent four 270-minute liquid mixed-meal tests (480 kcal per meal), receiving intravenous infusions of GIP (4 pmol/kg/min), GLP-1 (1 pmol/kg/min), combined GIP + GLP-1, or saline as placebo.
Investigators measured blood glucose, gastric emptying, appetite-related parameters, cardiovascular responses, bone resorption markers, and ad libitum food intake. Subjects continued their basal insulin but withheld other medications, including bolus insulin, from 10 p.m. on the preceding night.
Key findings
These results confirm that key physiological pathways mediated by GIP and GLP-1 do not require pancreatic tissue or endogenous pancreatic hormones. These insights offer a refined physiological rationale for utilizing incretin-based therapies in pancreatogenic diabetes, metabolic disorders, and post-pancreatectomy care.
Diabetes, Obesity and Metabolism
Acute GIP and GLP-1 Administration Exerts Differential Metabolic Effects in Totally Pancreatectomised Individuals
Liva S L Krogh et al.
Comments (0)