CONTEXT: Brown adipose tissue (BAT) is a metabolically highly active organ with increased thermogenic activity in rodents exposed to cold temperature. Recently its presence in the cervical adipose tissue of human adults and its association with a favorable metabolic phenotype have been reported. OBJECTIVE: The objective of the study was to determine the prevalence of retroperitoneal BAT in human adults. DESIGN: This was an observational cohort study. SETTING: The study was conducted at a tertiary referral hospital. PATIENTS: Fifty-seven patients who underwent surgery for benign adrenal tumors were included in this study. MAIN OUTCOME MEASURES: Prevalence of retroperitoneal BAT adjacent to the removed adrenal tumor as determined by uncoupling protein 1 (UCP1) protein and mRNA expression was measured. RESULTS: Using protein and mRNA expression analysis, we detected UCP1 protein in 26 of 57 patients (45.6%) as well as high mRNA expression of genes characteristic for brown adipocytes, independent of the adrenal tumor type. The presence of brown adipocytes within the retroperitoneal fat was associated with a significantly lower outdoor temperature during the month prior to surgery. Importantly, UCP1 expression on both mRNA and protein level was inversely correlated to outdoor temperature, whereas body mass index, sex, age, and diabetes status were not. CONCLUSIONS: These findings suggest that human retroperitoneal adipose tissue can acquire a BAT phenotype, thereby adapting to environmental challenges. These adaptive processes might provide a valuable therapeutic target in the treatment of obesity and insulin resistance.
CONTEXT: Brown adipose tissue (BAT) is a metabolically highly active organ with increased thermogenic activity in rodents exposed to cold temperature. Recently its presence in the cervical adipose tissue of human adults and its association with a favorable metabolic phenotype have been reported. OBJECTIVE: The objective of the study was to determine the prevalence of retroperitoneal BAT in human adults. DESIGN: This was an observational cohort study. SETTING: The study was conducted at a tertiary referral hospital. PATIENTS: Fifty-seven patients who underwent surgery for benign adrenal tumors were included in this study. MAIN OUTCOME MEASURES: Prevalence of retroperitoneal BAT adjacent to the removed adrenal tumor as determined by uncoupling protein 1 (UCP1) protein and mRNA expression was measured. RESULTS: Using protein and mRNA expression analysis, we detected UCP1 protein in 26 of 57 patients (45.6%) as well as high mRNA expression of genes characteristic for brown adipocytes, independent of the adrenal tumor type. The presence of brown adipocytes within the retroperitoneal fat was associated with a significantly lower outdoor temperature during the month prior to surgery. Importantly, UCP1 expression on both mRNA and protein level was inversely correlated to outdoor temperature, whereas body mass index, sex, age, and diabetes status were not. CONCLUSIONS: These findings suggest that human retroperitoneal adipose tissue can acquire a BAT phenotype, thereby adapting to environmental challenges. These adaptive processes might provide a valuable therapeutic target in the treatment of obesity and insulin resistance.
Authors: Thorsten Gnad; Saskia Scheibler; Ivar von Kügelgen; Camilla Scheele; Ana Kilić; Anja Glöde; Linda S Hoffmann; Laia Reverte-Salisa; Philipp Horn; Samet Mutlu; Ali El-Tayeb; Mathias Kranz; Winnie Deuther-Conrad; Peter Brust; Martin E Lidell; Matthias J Betz; Sven Enerbäck; Jürgen Schrader; Gennady G Yegutkin; Christa E Müller; Alexander Pfeifer Journal: Nature Date: 2014-10-15 Impact factor: 49.962
Authors: Laurent Vergnes; Graeme R Davies; Jason Y Lin; Michael W Yeh; Masha J Livhits; Avital Harari; Michael E Symonds; Harold S Sacks; Karen Reue Journal: J Clin Endocrinol Metab Date: 2016-08-30 Impact factor: 5.958
Authors: Katarina Klepac; Ana Kilić; Thorsten Gnad; Loren M Brown; Beate Herrmann; Andrea Wilderman; Aileen Balkow; Anja Glöde; Katharina Simon; Martin E Lidell; Matthias J Betz; Sven Enerbäck; Jürgen Wess; Marc Freichel; Matthias Blüher; Gabi König; Evi Kostenis; Paul A Insel; Alexander Pfeifer Journal: Nat Commun Date: 2016-03-09 Impact factor: 14.919