Measuring the Effect of a Study Meal on Portal Concentrations of Glucagon-Like Peptide 1 (GLP-1) in Non Diabetic and Diabetic Patients with Liver Cirrhosis: Transjugular Intrahepatic Portosystemic Stent Shunt (TIPSS) as a New Method for Metabolic Measurements

Background: Diabetes in liver cirrhosis is associated with a blunted insulin response, which might be explained by an impaired release of the incretin hormone glucagon-like peptide 1 (GLP-1) into the portal circulation. Aims: To investigate basal and stimulated portal venous and peripheral GLP-1 concentrations in non-diabetic (ND) and diabetic (D) patients with liver cirrhosis undergoing transjugular intrahepatic portosystemic stent shunt (TIPSS) implantation. Patients and Methods: After elective TIPSS portalvenous and peripheral probes were drawn from 10 ND and 10 D patients with stable liver disease during an oral metabolic test and plasma glucose, immunoreactive GLP-1, insulin and C-peptide were measured. Results: The study meal led to a significant rise in portal GLP-1 levels in ND and D. Basal and stimulated portal GLP-1 concentrations were not significantly different between ND and D. Peripheral GLP-1 did not differ significantly from portal venous levels. Insulin response in ND was more pronounced in the portal blood than in the periphery and was absent in D. Conclusion: TIPSS allows a direct evaluation of hormonal changes in the portal circulation during an oral metabolic tolerance test. A disturbed GLP-1 secretion does not play a role in blunting the insulin response observed in patients with hepatogenous diabetes.