Gluco-regulatory effects of the insulinotropic and glucagonotropic gut hormone glucose-dependent insulinotropic polypeptide (GIP) in type 1 diabetes (T1D) are unclear. We evaluated the effects of exogenous and endogenous GIP on plasma glucose excursions in a setting of prandial insulin over-dose and physical activity after meal ingestion.

In a randomized, placebo-controlled, double-blinded, crossover study, 12 men with T1D (age [mean±SD]: 26±6.6 years; BMI: 23±2.3 kg/m2; HbA1c: 6.5±2.7% (48.4±6.3 mmol/mol); diabetes duration: 11.3±5.5 years; plasma C-peptide <200 pmol/L) underwent three separate study days involving a liquid mixed meal test with 125% of regular prandial insulin dose, 30 minutes of intermediate bicycling (60 minutes after mixed-meal), and 270 minute infusions of GIP, the GIP receptor antagonist GIP(3-30)NH2 and placebo, respectively.

The GIP infusion attenuated postprandial plasma glucose excursions (Cmax-Cmin) by [mean±SEM] 1.5±0.5 mmol/L and 0.92±0.56 mmol/L compared to GIP(3-30)NH2 and placebo, respectively (P=0.03). Infused glucose needed to avoid plasma glucose <2.5 mmol/L was similar on all 3 study days (P=0.13).

In conclusion, GIP infusion seems to attenuate postprandial plasma glucose excursions without significantly increasing the need of glucose to avoid hypoglycemia in patients with T1D.

Disclosure

B. Hoe: None. S.M. Nguyen Heimbürger: None. L.S. Gasbjerg: Stock/Shareholder; Self; Antag Therapeutics. M.B. Lynggaard: None. B. Hartmann: None. J.J. Holst: Advisory Panel; Self; AstraZeneca, Merck Sharp & Dohme Corp., Novo Nordisk A/S, Zealand Pharma A/S. Other Relationship; Spouse/Partner; Antag Therapeutics. T. Vilsbøll: Advisory Panel; Self; AstraZeneca, Mundipharma International, Novo Nordisk A/S, Sun Pharmaceutical Industries Ltd. Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Lilly Diabetes, Medscape, Merck Sharp & Dohme Corp., Sanofi. A. Lund: Speaker’s Bureau; Self; AstraZeneca, Novo Nordisk A/S, Sanofi. S. Engberg: None. T.F. Dejgaard: Advisory Panel; Self; Novo Nordisk A/S. Consultant; Self; Boehringer Ingelheim International GmbH, Novo Nordisk A/S. Speaker’s Bureau; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Novo Nordisk A/S. M.B. Christensen: None. F.K. Knop: Advisory Panel; Self; AstraZeneca, Merck Sharp & Dohme Corp., Mundipharma International, Novo Nordisk A/S, Sanofi. Consultant; Self; Carmot Therapeutics, Inc., Eli Lilly and Company, Novo Nordisk A/S. Research Support; Self; AstraZeneca, Gubra, Novo Nordisk A/S, Sanofi, Zealand Pharma A/S. Speaker’s Bureau; Self; AstraZeneca, Lupin Pharmaceuticals, Inc., Merck Sharp & Dohme Corp., Norgine B.V., Novo Nordisk A/S.

Funding

The Leona M. and Harry B. Helmsley Charitable Trust (2018PG-T1D037)

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