title: Temperature-acclimated brown adipose tissue modulates insulin sensitivity in humans.
abstract: In rodents, brown adipose tissue (BAT) regulates cold- and diet-induced thermogenesis (CIT; DIT). Whether BAT recruitment is reversible and how it impacts on energy metabolism have not been investigated in humans. We examined the effects of temperature acclimation on BAT, energy balance, and substrate metabolism in a prospective crossover study of 4-month duration, consisting of four consecutive blocks of 1-month overnight temperature acclimation (24 °C [month 1] → 19 °C [month 2] → 24 °C [month 3] → 27 °C [month 4]) of five healthy men in a temperature-controlled research facility. Sequential monthly acclimation modulated BAT reversibly, boosting and suppressing its abundance and activity in mild cold and warm conditions (P < 0.05), respectively, independent of seasonal fluctuations (P < 0.01). BAT acclimation did not alter CIT but was accompanied by DIT (P < 0.05) and postprandial insulin sensitivity enhancement (P < 0.05), evident only after cold acclimation. Circulating and adipose tissue, but not skeletal muscle, expression levels of leptin and adiponectin displayed reciprocal changes concordant with cold-acclimated insulin sensitization. These results suggest regulatory links between BAT thermal plasticity and glucose metabolism in humans, opening avenues to harnessing BAT for metabolic benefits.
authors: Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD.
authors: Paul
authors: P
authors: Lee
authors: Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD.
authors: Sheila
authors: S
authors: Smith
authors: Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD.
authors: Joyce
authors: J
authors: Linderman
authors: Department of Nutrition, Clinical Center, National Institutes of Health, Bethesda, MD.
authors: Amber B
authors: AB
authors: Courville
authors: Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD.
authors: Robert J
authors: RJ
authors: Brychta
authors: PET Department, Clinical Center, National Institutes of Health, Bethesda, MD.
authors: William
authors: W
authors: Dieckmann
authors: Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD.
authors: Charlotte D
authors: CD
authors: Werner
authors: Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD.
authors: Kong Y
authors: KY
authors: Chen
authors: Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD Division of Endocrinology and Metabolism, Virginia Commonwealth University, Richmond, VA fsceli@vcu.edu.
authors: Francesco S
authors: FS
authors: Celi
mesh_terms: D000064:Acclimatization; D000273:Adipose Tissue / Q000378:metabolism; D002001:Adipose Tissue, Brown / Q000378:metabolism*; D000328:Adult; D018592:Cross-Over Studies; D004734:Energy Metabolism / Q000502:physiology; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism; D011446:Prospective Studies; D013696:Temperature; D022722:Thermogenesis / Q000502:physiology; D055815:Young Adult