PET imaging during hypoglycaemia to study adipose tissue metabolism

Eur J Clin Invest. 2019 Jul;49(7):e13120. doi: 10.1111/eci.13120. Epub 2019 Apr 29.

Abstract

Background: Disturbances in adipose tissue glucose uptake may play a role in the pathogenesis of type 2 diabetes, yet its examination by 2-deoxy-2-[18 F]fluorodeoxyglucose ([18 F]FDG) PET/CT is challenged by relatively low uptake kinetics. We tested the hypothesis that performing [18 F]FDG PET/CT during a hypoglycaemic clamp would improve adipose tissue tracer uptake to allow specific comparison of adipose tissue glucose handling between people with or without type 2 diabetes.

Design: We enrolled participants with or without diabetes who were at least overweight, to undergo a hyperinsulinaemic hypoglycaemic clamp or a hyperinsulinaemic euglycaemic clamp (n = 5 per group). Tracer uptake was quantified using [18 F]FDG PET/CT.

Results: Hypoglycaemic clamping increased [18 F]FDG uptake in visceral adipose tissue of healthy participants (P = 0.002). During hypoglycaemia, glucose uptake in visceral adipose tissue of type 2 diabetic participants was lower as compared to healthy participants (P < 0.0005). No significant differences were observed in skeletal muscle, liver or pancreas.

Conclusions: The present findings indicate that [18 F]FDG PET/CT during a hypoglycaemic clamp provides a promising new research tool to evaluate adipose tissue glucose metabolism. Using this method, we observed a specific impairment in visceral adipose tissue [18 F]FDG uptake in type 2 diabetes, suggesting a previously underestimated role for adipose tissue glucose handling in type 2 diabetes.

Keywords: [18F]FDG PET; adipose tissue; glucose metabolism; obesity; type 2 diabetes mellitus.

MeSH terms

  • Adipose Tissue / diagnostic imaging
  • Adipose Tissue / metabolism*
  • Adult
  • Blood Glucose / metabolism
  • Case-Control Studies
  • Diabetes Mellitus, Type 2 / diagnostic imaging
  • Diabetes Mellitus, Type 2 / drug therapy
  • Diabetes Mellitus, Type 2 / metabolism
  • Female
  • Fluorodeoxyglucose F18 / pharmacokinetics
  • Glucose / administration & dosage
  • Glucose / pharmacokinetics
  • Humans
  • Hypoglycemia / diagnostic imaging*
  • Hypoglycemia / metabolism
  • Hypoglycemic Agents / administration & dosage
  • Male
  • Positron Emission Tomography Computed Tomography / methods
  • Radiopharmaceuticals / pharmacokinetics
  • Sweetening Agents / administration & dosage
  • Sweetening Agents / pharmacokinetics

Substances

  • Blood Glucose
  • Hypoglycemic Agents
  • Radiopharmaceuticals
  • Sweetening Agents
  • Fluorodeoxyglucose F18
  • Glucose