Association between brown adipose tissue and bone mineral density in humans

Abstract

Background. Brown adipose tissue (BAT) seems to play a role in bone morphogenesis. A negative association has been reported between BAT and bone mineral density (BMD) in women, but not in men. A panel of experts has recently published a set of recommendations for BAT assessment, and thus, to re-address previously reported associations is needed. This study aimed to investigate the association between cold-induced BAT glucose uptake and BMD in young healthy adults Methods. 98 healthy adults (58 women; 22±2.2 years old; 24.3± 4.5 kg/m2) cold-induced BAT was assessed by means of an 18F fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) scan preceded by a personalized cold stimulation. The cold exposure consisted in 2 hours in a mild cold room at 19.5-20ºC wearing a water perfused cooling vest set 4ºC above the individual shivering threshold. total body and lumbar spine BMD were assessed by a whole-body DXA scan. Results. We found no association between BMD and cold-induced BAT volume, mean, and maximal activity (All P>0.1) in neither young and healthy men nor women. These results remained unchanged when adjusting by height, by body composition, and by objectively assessed physical activity. Sensitivity analyses using the criteria to quantify cold-induced BAT-related parameters applied in previous studies did not change the results. Conclusions. In summary, our study shows that there is no association between cold-induced BAT and BMD in young healthy adults. Moreover, our data support the notion that previously shown associations between BAT and BMD in healthy non-calorically restricted individuals, could be driven by methodological issues related to BAT assessment and/or sample size limitations.