Brown adipose tissue estimated with the magnetic resonance imaging fat fraction is associated with glucose metabolism in adolescents

Abstract

Summary Background Despite therapeutic potential against obesity and diabetes, the associations of brown adipose tissue (BAT) with glucose metabolism in young humans are relatively unexplored. Objectives To investigate possible associations between magnetic resonance imaging (MRI) estimates of BAT and glucose metabolism, whilst considering sex, age, and adiposity, in adolescents with normal and overweight/obese phenotypes. Methods In 143 subjects (10‐20 years), MRI estimates of BAT were assessed as cervical‐supraclavicular adipose tissue (sBAT) fat fraction (FF) and T2* from water‐fat MRI. FF and T2* of neighbouring subcutaneous adipose tissue (SAT) were also assessed. Adiposity was estimated with a standardized body mass index, the waist‐to‐height ratio, and abdominal visceral and subcutaneous adipose tissue volumes. Glucose metabolism was represented by the 2h plasma glucose concentration, the Matsuda index, the homeostatic model assessment of insulin resistance, and the oral disposition index; obtained from oral glucose tolerance tests. Results sBAT FF and T2* correlated positively with adiposity before and after adjustment for sex and age. sBAT FF, but not T2*, correlated with 2h glucose and Matsuda index, also after adjustment for sex, age, and adiposity. The association with 2h glucose persisted after additional adjustment for SAT FF. Conclusions The association between sBAT FF and 2h glucose, observed independently of sex, age, adiposity, and SAT FF, indicates a role for BAT in glucose metabolism, which potentially could influence the risk of developing diabetes. The lacking association with sBAT T2* might be due to FF being a superior biomarker for BAT and/or to methodological limitations in the T2* quantification.

Differential Effects of 17,18-EEQ and 19,20-EDP Combined with Soluble Epoxide Hydrolase Inhibitor t-TUCB on Diet-Induced Obesity in Mice

“…Brown adipose tissue (BAT) has emerged as a promising target for obesity treatment and prevention due to its ability to increase energy expenditure through nonshivering thermogenesis [ 6 , 7 , 8 , 9 ]. BAT activation by cold exposure has been reported to improve glucose and lipid metabolism in rodents and humans due to its thermogenic function [ 10 , 11 , 12 ]. Therefore, strategies that enhance BAT activation and improve BAT function may confer beneficial diet-induced obesity and associated metabolic comorbidities.…”

Measuring Brown Fat Using MRI and Implications in the Metabolic Syndrome

“…The FF of BAT positively correlated with 2-hour glucose levels independent of sex, age, site, and adiposity, while T 2 * showed insignificance, suggesting the ability of BAT to control glucose levels and/or dissipate triglycerides and free fatty acids. 92 In a study by Franssens et al, 86 the absence of type 2 diabetes mellitus showed the most FF difference between supraclavicular and subcutaneous adipose tissue, demonstrating a lower BAT prevalence. FF was also used to explore the pharmacological mechanism of drugs used to treat type 2 diabetes mellitus.…”

Magnetic Resonance Imaging Techniques for Brown Adipose Tissue Detection

“…To detect and characterize BAT, chemical-shift encoding-based water–fat imaging techniques have been used on the supraclavicular adipose tissue in humans across all ages. Studies in infants ( 48 , 84 , 85 ), children ( 79 ), adolescents ( 86 ), and adults ( 81 , 87 – 94 ) have demonstrated the feasibility of this technique in humans. A favored method to measure BAT fat fraction is the measurement of the PDFF, which has been used in several studies for human BAT on grounds of its robustness and standardization ( 81 , 88 , 92 , 94 ).…”

“…These correlations are of interest regarding potential therapeutic targets for obesity. More interestingly, it has been shown that activation of BAT increases glucose and triglyceride clearance in humans, potentially decreasing the risk of developing diabetes and other obesity comorbidities ( 4 , 86 , 108 , 112 , 113 ). In human adults with obesity, effects of cold and insulin on BAT activity were reported to be restricted ( 114 – 116 ).…”