Total-body Glucose Utilization in Obesity

Summary

There are three goals for this study. One is to investigate how different emotions and exposure to cold affect blood flow in the body. The second aim is to study how insulin affects blood flow and tissue glucose uptake, and to study whether this effect is altered in obesity. Last, the study focuses on establishing the lowest dose of a PET radiotracer, oxygen-15 labelled water, that can be used in clinical studies with a new whole-body PET scanner.

Conditions

• Obesity and Overweight

Interventions

BEHAVIORAL

Movies

Participants will watch eight short movie clips, and the changes different emotions evoked by the clips will be studied using H2\[15O\]O PET/CT.

BEHAVIORAL

Cold

Participants will be studied with H2\[15O\]O PET/CT while one of their legs will be exposed to cold to study the effects of cold stimulus on whole-body blood flow.

DRUG

Hyperinsulinemic euglycemic clamp

Participants will be administered intravenous fast acting insulin (NovoRapid, Novo Nordisk, 1 mU/m2 body surface area/min) together with 20 % glucose to maintain normal glucose values (5.0 mmol/L) to study the effects of insulin on whole body blood flow with H2\[15O\]O PET/CT, and to assess tissue insulin-stimulated glucose uptake with \[18F\]FDG PET/CT.

RADIATION

H2[15O]O PET/CT

H2\[15O\]O PET/CT, with a dose of 25-700 MB/bolus repeated 2-8 times per scan.

RADIATION

[18F]FDG PET/CT

Whole-body \[18F\]FDG PET/CT scan to study tissue glucose uptake, dose 100 MBq

DRUG

CEUS or Contrast enhanced Ultrasound

Contrast-enhanced ultrasound of left forearm muscles is performed during fasting and after 30-40 minutes of hyperinsulinemia

Sponsors & Collaborators

• Turku University Hospital

  lead OTHER_GOV

Principal Investigators

• Lauri Nummenmaa, Professor · University of Turku

• Pirjo Nuutila, professor · University of Turku, Turku University Hospital

Study Design

Allocation

NON_RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

20 Years

Max Age

60 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2023-01-25

Primary Completion

2024-12-31

Completion

2024-12-31

Countries

• Finland

Study Locations