Author
CHONDRONIKOLA, MARIA - Shriners Hospital For Children | |
VOLPI, ELENA - University Of Texas Medical Branch | |
BORSHEIM, ELISABET - Arkansas Children'S Nutrition Research Center (ACNC) | |
PORTER, CRAIG - Shriners Hospital For Children | |
ANNAMALAI, PALAM - University Of Texas Medical Branch | |
ENERBACK, SVEN - University Of Gothenburg | |
LIDELL, MARTIN - University Of Gothenburg | |
SARAF, MANISH - Shriners Hospital For Children | |
LABBE, SEBASTIEN - Quebec Heart And Lung Research Institute | |
HURREN, NICHOLAS - Shriners Hospital For Children | |
YFANTI, CHRISTINA - Shriners Hospital For Children | |
CHAO, TONY - Shriners Hospital For Children | |
ANDERSEN, CLARK - Shriners Hospital For Children | |
CESANI, FERNANDO - University Of Texas Medical Branch | |
HAWKINS, HAL - University Of Texas Medical Branch | |
SIDOSSIS, LABROS - Shriners Hospital For Children |
Submitted to: Diabetes
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/10/2014 Publication Date: 12/1/2014 Citation: Chondronikola, M., Volpi, E., Borsheim, E., Porter, C., Annamalai, P., Enerback, S., Lidell, M.E., Saraf, M.K., Labbe, S.M., Hurren, N.M., Yfanti, C., Chao, T., Andersen, C.R., Cesani, F., Hawkins, H., Sidossis, L.S. 2014. Brown adipose tissue improves whole-body glucose homeostasis and insulin sensitivity in humans. Diabetes. 63:4089-4099. Interpretive Summary: Brown adipose tissue (BAT) is a specialized fat tissue that is most abundant in human neonates and is believed to contribute significantly to regulation of thermogenesis (heat production) during this critical period of development. The importance of BAT in terms of fuel metabolism and impact on whole-body metabolism remains to be fully elaborated. Adult humans have recently been shown to also have brown adipose tissue (BAT), opening the door for clinical research to determine the roles of BAT in normal physiology and pathophysiology. In adults, BAT is associated with leanness and better blood sugar regulation, suggesting that BAT may be protective against obesity and diabetes, unlike other fat tissue. The unique feature of BAT that explains the proposed effects on obesity and glucose control is the abundance of mitochondria, which contain a thermogenic factor called uncoupling protein 1 (UCP1). The aim of this study was to investigate the effect of 5–8 hours of cold-induced BAT activation on whole-body glucose handling. Twelve men were studied under cold exposure and normal temperature. Cold increased resting energy expenditure (REE), usage of blood glucose for energy production, and insulin-stimulated glucose uptake in individuals who possess significant BAT activity, but not in those without or with minimal BAT activity. The current data support a significant role for BAT in regulation of energy expenditure, blood sugar and insulin sensitivity in humans, and support that BAT may function as an "antidiabetic tissue" in humans. Studies of BAT metabolism in adults can shed light on the potential function of this tissue in human infants. Furthermore, studies may be conducted to determine BAT's role in fat and sugar metabolism in response to changes in diet, physical activity/exercise, and obesity. Technical Abstract: Brown adipose tissue (BAT) has attracted scientific interest as an antidiabetic tissue owing to its ability to dissipate energy as heat. Despite a plethora of data concerning the role of BAT in glucose metabolism in rodents, the role of BAT (if any) in glucose metabolism in humans remains unclear. To investigate whether BAT activation alters whole-body glucose homeostasis and insulin sensitivity in humans, we studied seven BAT-positive (BAT(+)) men and five BAT-negative (BAT(-)) men under thermoneutral conditions and after prolonged (5-8 h) cold exposure (CE). The two groups were similar in age, BMI, and adiposity. CE significantly increased resting energy expenditure, whole-body glucose disposal, plasma glucose oxidation, and insulin sensitivity in the BAT(+) group only. These results demonstrate a physiologically significant role of BAT in whole-body energy expenditure, glucose homeostasis, and insulin sensitivity in humans, and support the notion that BAT may function as an antidiabetic tissue in humans. |