Objective: Human brown adipose tissue (BAT) has gained considerable attention as a potential therapeutic target for obesity and its related cardiometabolic diseases; however, whether the gut... Show moreObjective: Human brown adipose tissue (BAT) has gained considerable attention as a potential therapeutic target for obesity and its related cardiometabolic diseases; however, whether the gut microbiota might be an efficient stimulus to activate BAT metabolism remains to be ascertained. We aimed to investigate the association of fecal microbiota composition with BAT volume and activity and mean radiodensity in young adults. Methods: 82 young adults (58 women, 21.8 +/- 2.2 years old) participated in this cross-sectional study. DNA was extracted from fecal samples and 16S rRNA sequencing was performed to analyse the fecal microbiota composition. BAT was determined via a static F-18-fluorodeoxyglucose (F-18-FDG) positron emission tomography-computed tomography scan (PET/CT) after a 2 h personalized cooling protocol. F-18-FDG uptake was also quantified in white adipose tissue (WAT) and skeletal muscles. Results: The relative abundance of Akkermansia, Lachnospiraceae sp. and Ruminococcus genera was negatively correlated with BAT volume, BAT SUVmean and BAT SUVpeak (all rho <= - 0.232, P <= 0.027), whereas the relative abundance of Bifidobacterium genus was positively correlated with BAT SUVmean and BAT SUVpeak (all rho >= 0.262, P <= 0.012). On the other hand, the relative abundance of Sutterellaceae and Bifidobacteriaceae families was positively correlated with F-18-FDG uptake by WAT and skeletal muscles (all rho >= 0.213, P <= 0.042). All the analyses were adjusted for the PET/CT scan date as a proxy of seasonality. Conclusion: Our results suggest that fecal microbiota composition is involved in the regulation of BAT and glucose uptake by other tissues in young adults. Further studies are needed to confirm these findings. Show less
ObjectiveHuman brown adipose tissue (BAT) has gained considerable attention as a potential therapeutic target for obesity and its related cardiometabolic diseases; however, whether the gut... Show moreObjectiveHuman brown adipose tissue (BAT) has gained considerable attention as a potential therapeutic target for obesity and its related cardiometabolic diseases; however, whether the gut microbiota might be an efficient stimulus to activate BAT metabolism remains to be ascertained. We aimed to investigate the association of fecal microbiota composition with BAT volume and activity and mean radiodensity in young adults.Methods82 young adults (58 women, 21.8 ± 2.2 years old) participated in this cross-sectional study. DNA was extracted from fecal samples and 16S rRNA sequencing was performed to analyse the fecal microbiota composition. BAT was determined via a static 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography scan (PET/CT) after a 2 h personalized cooling protocol. 18F-FDG uptake was also quantified in white adipose tissue (WAT) and skeletal muscles.ResultsThe relative abundance of Akkermansia, Lachnospiraceae sp. and Ruminococcus genera was negatively correlated with BAT volume, BAT SUVmean and BAT SUVpeak (all rho ≤ − 0.232, P ≤ 0.027), whereas the relative abundance of Bifidobacterium genus was positively correlated with BAT SUVmean and BAT SUVpeak (all rho ≥ 0.262, P ≤ 0.012). On the other hand, the relative abundance of Sutterellaceae and Bifidobacteriaceae families was positively correlated with 18F-FDG uptake by WAT and skeletal muscles (all rho ≥ 0.213, P ≤ 0.042). All the analyses were adjusted for the PET/CT scan date as a proxy of seasonality.ConclusionOur results suggest that fecal microbiota composition is involved in the regulation of BAT and glucose uptake by other tissues in young adults. Further studies are needed to confirm these findings. Show less
Our increasing obesogenic and aging society has resulted in a steeply increasing prevalence of cardiometabolic diseases. The main underlying reason is our modern lifestyle with respect to higher... Show moreOur increasing obesogenic and aging society has resulted in a steeply increasing prevalence of cardiometabolic diseases. The main underlying reason is our modern lifestyle with respect to higher availability and intake of food, which often appears unhealthy, and lower energy expenditure related to a sedentary lifestyle. Although the most efficient ways to slow this high prevalence of obesity are just eating less and more healthy, and moving more, to reduce energy intake and increase energy expenditure, respectively, current strategies to achieve this in the long-term are still both insufficient and ineffective, and novel strategies are still eagerly warranted.This thesis emphasizes dietary butyrate as a promising and feasible therapeutic strategy to combat obesity and related cardiometabolic diseases with respect to not only reducing appetite but also activating brown adipose tissue. In a series of subsequent mechanistic studies, we elucidated the mechanisms underlying these metabolic properties systematically from gut to the brain, showing the involvement of gut microbiota, intestinal GLP-1 secretion, vagal nerve activation, and finally central GLP-1 receptor signaling to inhibit NPY neuronal activation. The findings of this thesis provide valuable information on the development of novel therapeutic strategies for combating obesity and associated cardiometabolic diseases. Show less
