TY - JOUR

T1 - The role of glucagon-like peptide 1 in the postprandial effects of metformin in type 2 diabetes

T2 - a randomized crossover trial

AU - Hansen, Laura S

AU - Gasbjerg, Lærke S

AU - Brønden, Andreas

AU - Dalsgaard, Niels B

AU - Bahne, Emilie

AU - Stensen, Signe

AU - Hellmann, Pernille H

AU - Rehfeld, Jens F.

AU - Hartmann, Bolette

AU - Wever Albrechtsen, Nicolai J

AU - Holst, Jens J

AU - Vilsbøll, Tina

AU - Knop, Filip K

N1 - © The Author(s) 2024. Published by Oxford University Press on behalf of European Society of Endocrinology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.

PY - 2024

Y1 - 2024

N2 - AIMS: Although metformin is widely used for treatment of type 2 diabetes (T2D), its glucose-lowering mechanisms remains unclear. Using the glucagon-like peptide 1 (GLP-1) receptor (GLP-1R) antagonist exendin(9-39)NH2, we tested the hypothesis that postprandial GLP-1-mediated effects contribute to the glucose-lowering potential of metformin in T2D.METHODS: In a randomised, placebo-controlled, double-blind, crossover study, 15 individuals with T2D (median HbA1c 50 mmol/mol (6.7%), BMI 30.1 kg/m2, age 71 years) underwent, in randomised order, 14 days of metformin and placebo treatment, respectively. Each treatment period was preceded by 14 days without any glucose-lowering medicine and concluded by two 4-hour mixed meal tests performed in randomised order and separated by >24 hours with either continuous intravenous exendin(9-39)NH2 or saline infusion.RESULTS: Compared to placebo, metformin treatment lowered fasting plasma glucose (mean of differences (MD) 1.4 mmol/l×min (95% CI 0.8-2.0)) as well as postprandial plasma glucose excursions during both saline infusion (MD 186 mmol/l×min (95% CI 64-307)) and exendin(9-39)NH2 infusion (MD 268 mmol/l×min (95% CI 108-427)). The metformin-induced improvement in postprandial glucose tolerance was unaffected by GLP-1R antagonization (MD 82 mmol/l×min (95% CI -6,564-170)). Metformin treatment increased fasting plasma GLP-1 (MD 1.7 pmol/l×min (95% CI 0.39-2.9)) but did not affect postprandial GLP-1 responses (MD 820 pmol/l×min (95% CI -1,750-111)).CONCLUSIONS: Using GLP-1R antagonization, we could not detect GLP-1-mediated postprandial glucose-lowering effect of metformin in individuals with T2D. We show that two weeks of metformin treatment increases fasting plasma GLP-1, which may contribute to metformin's beneficial effect on fasting plasma glucose in T2D.TRIAL REGISTRATION: Clinicaltrials.gov NCT03246451.

AB - AIMS: Although metformin is widely used for treatment of type 2 diabetes (T2D), its glucose-lowering mechanisms remains unclear. Using the glucagon-like peptide 1 (GLP-1) receptor (GLP-1R) antagonist exendin(9-39)NH2, we tested the hypothesis that postprandial GLP-1-mediated effects contribute to the glucose-lowering potential of metformin in T2D.METHODS: In a randomised, placebo-controlled, double-blind, crossover study, 15 individuals with T2D (median HbA1c 50 mmol/mol (6.7%), BMI 30.1 kg/m2, age 71 years) underwent, in randomised order, 14 days of metformin and placebo treatment, respectively. Each treatment period was preceded by 14 days without any glucose-lowering medicine and concluded by two 4-hour mixed meal tests performed in randomised order and separated by >24 hours with either continuous intravenous exendin(9-39)NH2 or saline infusion.RESULTS: Compared to placebo, metformin treatment lowered fasting plasma glucose (mean of differences (MD) 1.4 mmol/l×min (95% CI 0.8-2.0)) as well as postprandial plasma glucose excursions during both saline infusion (MD 186 mmol/l×min (95% CI 64-307)) and exendin(9-39)NH2 infusion (MD 268 mmol/l×min (95% CI 108-427)). The metformin-induced improvement in postprandial glucose tolerance was unaffected by GLP-1R antagonization (MD 82 mmol/l×min (95% CI -6,564-170)). Metformin treatment increased fasting plasma GLP-1 (MD 1.7 pmol/l×min (95% CI 0.39-2.9)) but did not affect postprandial GLP-1 responses (MD 820 pmol/l×min (95% CI -1,750-111)).CONCLUSIONS: Using GLP-1R antagonization, we could not detect GLP-1-mediated postprandial glucose-lowering effect of metformin in individuals with T2D. We show that two weeks of metformin treatment increases fasting plasma GLP-1, which may contribute to metformin's beneficial effect on fasting plasma glucose in T2D.TRIAL REGISTRATION: Clinicaltrials.gov NCT03246451.

U2 - 10.1093/ejendo/lvae095

DO - 10.1093/ejendo/lvae095

M3 - Journal article

C2 - 39049802

VL - 191

SP - 192

EP - 203

JO - European Journal of Endocrinology

JF - European Journal of Endocrinology

SN - 0804-4643

IS - 2

ER -