TY - JOUR

T1 - Preanalytical impact on the accuracy of measurements of glucagon, GLP-1 and GIP in clinical trials

AU - Rasmussen, Christine

AU - Richter, Michael M.

AU - Jensen, Nicole J.

AU - Heinz, Niklas

AU - Hartmann, Bolette

AU - Holst, Jens J.

AU - Kjeldsen, Sasha A.S.

AU - Wewer Albrechtsen, Nicolai J.

N1 - Publisher Copyright: © 2023 Medisinsk Fysiologisk Forenings Forlag (MFFF).

PY - 2023

Y1 - 2023

N2 - Background: Plasma concentrations of glucagon, GLP-1 and GIP are reported in numerous clinical trials as outcome measures but preanalytical guidelines are lacking. We addressed the impact of commonly used blood containers in metabolic research on measurements of glucagon, GLP-1 and GIP in humans. Methods: Seventeen overweight individuals were subjected to an overnight fast followed by an intravenous infusion of amino acids to stimulate hormonal secretion. Blood was sampled into five containers: EDTA-coated tubes supplemented with DMSO (control), a neprilysin inhibitor, aprotinin (a kallikrein inhibitor) or a DPP-4 inhibitor, and P800 tubes. Plasma was kept on ice before and after centrifugation and stored at −80 Celsius until batch analysis using validated sandwich ELISAs or radioimmunoassays (RIA). Results: Measures of fasting plasma glucagon did not depend on sampling containers, whether measured by ELISA or RIA. Amino acid-induced hyperglucagonemia was numerically higher when blood was collected into P800 tubes or tubes with aprotinin. The use of p800 tubes resulted in higher concentrations of GLP-1 by RIA compared to control tubes but not for measurements with sandwich ELISA. Plasma concentrations of GIP measured by ELISA were higher in control tubes and negatively affected by P800 and the addition of aprotinin. Conclusions: The choice of blood containers impacts on measurements of plasma concentrations of glucagon, GLP-1 and GIP, and based on this study, we recommend using EDTA-coated tubes without protease inhibitors or P800 tubes for measurements of glucagon, GLP-1 and GIP in clinical trials.

AB - Background: Plasma concentrations of glucagon, GLP-1 and GIP are reported in numerous clinical trials as outcome measures but preanalytical guidelines are lacking. We addressed the impact of commonly used blood containers in metabolic research on measurements of glucagon, GLP-1 and GIP in humans. Methods: Seventeen overweight individuals were subjected to an overnight fast followed by an intravenous infusion of amino acids to stimulate hormonal secretion. Blood was sampled into five containers: EDTA-coated tubes supplemented with DMSO (control), a neprilysin inhibitor, aprotinin (a kallikrein inhibitor) or a DPP-4 inhibitor, and P800 tubes. Plasma was kept on ice before and after centrifugation and stored at −80 Celsius until batch analysis using validated sandwich ELISAs or radioimmunoassays (RIA). Results: Measures of fasting plasma glucagon did not depend on sampling containers, whether measured by ELISA or RIA. Amino acid-induced hyperglucagonemia was numerically higher when blood was collected into P800 tubes or tubes with aprotinin. The use of p800 tubes resulted in higher concentrations of GLP-1 by RIA compared to control tubes but not for measurements with sandwich ELISA. Plasma concentrations of GIP measured by ELISA were higher in control tubes and negatively affected by P800 and the addition of aprotinin. Conclusions: The choice of blood containers impacts on measurements of plasma concentrations of glucagon, GLP-1 and GIP, and based on this study, we recommend using EDTA-coated tubes without protease inhibitors or P800 tubes for measurements of glucagon, GLP-1 and GIP in clinical trials.

KW - diabetes

KW - GIP

KW - GLP-1

KW - glucagon

KW - Preanalytics

U2 - 10.1080/00365513.2023.2294470

DO - 10.1080/00365513.2023.2294470

M3 - Journal article

C2 - 38127365

AN - SCOPUS:85180219617

VL - 83

SP - 591

EP - 598

JO - Scandinavian Journal of Clinical and Laboratory Investigation. Supplement

JF - Scandinavian Journal of Clinical and Laboratory Investigation. Supplement

SN - 0085-591X

IS - 8

ER -