GH administration decreases subcutaneous abdominal adipocyte size in men with abdominal obesity

Abstract

Objective: To investigate the effects of short-term GH administration on abdominal subcutaneous adipocyte size and CT attenuation in men with abdominal obesity.

Design: 6-week, randomized, double-blind, placebo-controlled study of GH (starting dose 2μg/kg/d) vs placebo of 15 abdominally obese men (mean age: 34±6years; mean BMI: 37.7±6.1kg/m2, mean IGF-1 SDS: -1.9±0.5) who underwent abdominal subcutaneous adipose tissue (SAT) aspirations to determine adipocyte size, CTs for body composition and measures of glucose tolerance at baseline and 6weeks. GH dosing was titrated to target IGF-1 levels in the upper normal age-appropriate range.

Results: GH administration decreased subcutaneous abdominal adipocyte size compared to placebo. Adipocyte size was positively associated with 120-min glucose and HOMA-IR and inversely associated with peak-stimulated GH and CT attenuation. CT attenuation of SAT was inversely associated with 120-min glucose and HOMA-IR and increased following GH administration.

Conclusion: In men with abdominal obesity, subcutaneous abdominal adipocyte size is positively associated with measures of impaired glucose tolerance and administration of GH at doses that raise IGF-1 levels within the normal range, decreases abdominal subcutaneous adipocyte size, suggesting that GH administration improves the health of adipose tissue. Clinical trials number: NCT00131378.

Keywords: Adipocytes; Adipose tissue; Adiposity; Computed tomography; Growth hormone; Obesity.

Conflict of interest statement

Disclosures: The authors have no conflict of interest to declare.

Copyright © 2017 Elsevier Ltd. All rights reserved.

Figures

Figure 1

Abdominal CT of a 43-year-old man with obesity (BMI: 46 kg/m2) before (A) and after (B) 6 weeks of GH administration, at doses which raised IGF-1 levels within the normal, age-appropriate range, resulting in increased CT attenuation of abdominal subcutaneous adipose tissues (asterisks). Images are presented using the same window and level. Bright-field images of H&E-stained paraffin-sectioned abdominal subcutaneous adipose tissue of the same subject before (C) and after (D) GH administration demonstrate a decrease in adipocyte cell size (20X magnification, bar represents 100μm).