Brown Adipose Tissue Activation Is Inversely Related to Central Obesity and Metabolic Parameters in Adult Human

Abstract

BackgroundRecent studies have shown that adult human possess active brown adipose tissue (BAT), which might be important in affecting obesity. However, the supporting evidence on the relationship between BAT and central obesity and metabolic profile in large population based studies is sparse.Methodology/Principal FindingsWe studied 4011 (2688 males and 1323 females) tumor-free Chinese adults aged 18-89 for BAT activities, visceral/subcutaneous fat areas (VFA/SFA), waist circumferences (WC) and metabolic parameters. We found that the prevalence of BAT was around 2.7% in our study participants, with a significant sexual difference (5.5% in the females vs. 1.3% in the males; p<0.0001). BAT detection was increased in low temperature and declined in elderly subjects. The BAT positive subjects had lower BMI (P<0.0001), less SFA (P<0.01), VFA (P<0.0001), WC (P<0.0001), lower fasting glucose and triglyceride levels (both P<0.01) and increased HDL cholesterol concentrations (P<0.0001), compared with the BAT negative subjects. Robust logistic regression revealed that after adjustment for covariates (including age, sex, BMI, VFA, SFA and WC), age and BMI in the males (0.92 [95%CI, 0.88-0.96] and 0.84 [95% CI, 0.75-0.96], both P ≤0.008) while age and VFA in the females (0.87 [95%CI, 0.83-0.91] and 0.98 [95%CI, 0.97-0.99], respectively, P<0.05) were independently associated with detectable BAT.Conclusions/SignificanceOur data suggest that decreased amount of active BAT might be associated with accumulation of visceral fat content and unfavorable metabolic outcomes.

Distinction of white, beige and brown adipocytes derived from mesenchymal stem cells

“…Interestingly, a potential solution to the problem of obesity-associated diseases has been found in brown fat, a type of adipose tissue that dissipates energy through a thermogenesis process. Previous studies showed that activated BAT is inversely correlated with BMI [65] , adipose tissue mass and insulin resistance. Thus, BAT is one of the best targets for creating strategies to treat obesity and obesity-associated diseases.…”

Brown adipose tissue density measured by near-infrared time-resolved spectroscopy in Japanese, across a wide age range

“…6,[13][14][15][16][17]19,21 BAT activity was found to be higher in women, in many oncology studies. [13][14][15][16][17]20 However, no sex differences were found in 18 FDG-PET∕CT studies with cold exposure. 6,22 The oncology studies had very large sample sizes but did not include cold exposure, whereas the studies using 18 FDG-PET∕CT with cold exposure had relatively small sample sizes.…”

“…We showed that body fatness parameters were negatively correlated with BAT-d, which is consistent with the results of various studies that used 18 FDG-PET∕CT, regardless of the presence of cold exposure. 6,[14][15][16][17]19,20 Although we should consider the possibility that the BAT-d was affected by subcutaneous fat thickness, 26 the subcutaneous fat thickness in the supraclavicular region is within a very narrow range and has little effect on the measured parameters. For instance, the fat thickness in the supraclavicular region ranged from 0.6 to 2.5 mm when evaluated by B-mode ultrasonography in this study.…”

“…1,18 Indeed, the 18 FDG-PET∕CT-positive BAT ratio is variable; in studies involving cancer patients without cold exposure, the ratio was found to be extremely low (∼5%). [11][12][13][14][15][16][17]19,20 However, in younger healthy individuals, who were exposed to cold, the ratio was much higher (∼50% to 100%). 3,6 With regards to the effect of AmT on the activation of BAT, the results are conflicting with one study demonstrating that the rise in the BAT activity was delayed by a few months in association with a beginning in the decline in the AmT 11 and the other study stating that BAT activity was higher in early winter than late winter or early spring.…”

Heterogeneity of adipose tissue in development and metabolic function

“…1). However, the amount of detectable active BAT in humans varies depending on age, body mass and season Wang et al, 2015), and shows higher prevalence in young, lean women than in men .…”