The presence of brown adipose tissue protects against arterial inflammation in young obese adults

642 Objectives: Since its recent rediscovery in human adults, brown adipose tissue has gained a lot of interest as a target against obesity and its associated metabolic disorders. Upon activation, BAT combusts high amounts of fatty acids and thus lowers plasma lipid levels protecting thereby against the development of atherosclerosis. Recent human data have shown a negative correlation between the presence of BAT and arterial inflammation. Here we aim to investigate the degree of arterial inflammation in young obese adults undergoing a 18F-FDG PET/CT study for the detection of BAT. Materials and Methods: 55 obese participants enrolled in a prospective imaging study underwent two consecutive 18F-FDG PET/CT examinations at thermoneutrality and after BAT activation using mild cold exposure. BAT was segmented according to the BARCIST criteria. We then divided the participants according to the 18F-FDG uptake in BAT positive (18 subjects) and BAT negative (37 subjects). The arterial inflammation was assessed in accordance with the EANM guidelines. Results: The presence of BAT was associated with significantly lower arterial inflammation in the aortic arch and in the ascending aorta (BAT positive versus BAT negative: 2,35 ± 0,1 vs 2,87 ± 0,07, p < 0,001, 2,56 ± 0,11 vs 3,08 ± 0,09, p = 0,001). Furthermore, we noticed strong negative correlations between BAT activation parameters (volume, SUVmean and cold induced thermogenesis) and arterial inflammation in the aortic arch (volume R = - 0,56, p = 0,01; SUVmean R = - 0,53, p = 0,02; CIT R = - 0,67, p = 0,002) and ascending aorta (volume R = - 0,6, p = 0,009; SUVmean R = - 0,29, p = n.s.; CIT R = - 0,39, p = n.s.). We also noticed a tendency towards lower circulating inflammation marker (CRP, IL-6) in subjects with BAT as compared to subjects without (n.s.). Conclusions: Our data show a strong negative correlation between brown fat activity and arterial inflammation suggesting a protective role of brown adipose tissue against atherosclerosis in young obese subjects. Conclusion: Our data show a strong negative correlation between brown fat activity and arterial inflammation suggesting a protective role of brown adipose tissue against atherosclerosis in young obese subjects.