NCT07398300

Insulin-Mediated Glucose Uptake and Organ Perfusion Assessed by Total-Body PET During GIP and GLP-1 Infusion

Dynamic Whole-Body FDG and H₂¹⁵O PET-CT to Assess Insulin-Mediated Glucose Uptake and Organ Perfusion During GIP and GLP-1 Infusion in Healthy Individuals and Patients With Type 2 Diabetes

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 36 (estimated)
• Sponsor: Rigshospitalet, Denmark · Academic / Other
• Sex: All
• Age: 23 Years – 64 Years
• Healthy volunteers: Accepted

Summary

This study investigates how the naturally occurring gut hormones GIP and GLP-1 influence whole-body glucose uptake and organ perfusion in humans. Using a state-of-the-art total-body PET-CT scanner, the study measures dynamic uptake of the glucose analogue 18F-FDG and blood flow using H₂¹⁵O across multiple organs during controlled elevations of plasma glucose and endogenous insulin secretion. The project consists of two sub-studies. Sub-study 1 includes healthy individuals who undergo three experimental visits with infusions of GIP, GLP-1, or saline (placebo) during a hyperglycemic clamp followed by FDG PET-CT scanning. Sub-study 2 includes healthy individuals and participants with type 2 diabetes who undergo two experimental visits with saline followed by either GIP or GLP-1 during a hyperglycemic clamp, combined with repeated H₂¹⁵O PET-CT measurements of perfusion. The primary aims are to quantify insulin-mediated skeletal muscle glucose uptake (sub-study 1) and skeletal muscle perfusion (sub-study 2). Secondary aims include assessment of glucose uptake and perfusion across adipose tissue, liver, and additional organs. The results will provide novel physiological insight into postprandial glucose metabolism and serve as reference data for future whole-body PET research.

Conditions

• Type 2 Diabetes
• Healhty

Interventions

Type	Name	Description
DRUG	GIP	Intravenous infusion of glucose-dependent insulinotropic polypeptide (GIP) consisting of a priming dose of 18 pmol/kg/min for 10 minutes followed by a steady-state infusion of 6 pmol/kg/min during a hyperglycemic clamp. Used to stimulate endogenous insulin secretion and mimic postprandial physiology
DRUG	GLP-1	Intravenous infusion of glucagon-like peptide-1 (GLP-1) consisting of a priming dose of 4.5 pmol/kg/min for 10 minutes followed by a steady-state infusion of 1.5 pmol/kg/min during a hyperglycemic clamp. Used to stimulate endogenous insulin secretion and mimic postprandial physiology.
OTHER	Saline (0.9% Sodium Chloride)	Intravenous infusion of isotonic saline administered as placebo. In sub-study 1, saline serves as a control condition; in sub-study 2, saline is infused for 15 minutes prior to hormone infusion.

Timeline

• Start date: 2026-03-12
• Primary completion: 2027-03-12
• Completion: 2027-05-01
• First posted: 2026-02-09
• Last updated: 2026-02-09

Locations

1 site across 1 country: Denmark