Short-term Cold Acclimation Recruits Brown Adipose Tissue in Obese Humans

Abstract

Recruitment of brown adipose tissue (BAT) has emerged as a potential tool to combat obesity and associated metabolic complications. Short-term cold acclimation has been shown not only to enhance the presence and activity of BAT in lean humans but also to improve the metabolic profile of skeletal muscle to benefit glucose uptake in patients with type 2 diabetes. Here we examined whether short-term cold acclimation also induced such adaptations in 10 metabolically healthy obese male subjects. A 10-day cold acclimation period resulted in increased cold-induced glucose uptake in BAT, as assessed by [18F]fluorodeoxyglucose positron emission tomography/computed tomography. BAT activity was negatively related to age, with a similar trend for body fat percentage. In addition, cold-induced glucose uptake in BAT was positively related to glucose uptake in visceral white adipose tissue, although glucose uptake in visceral and subcutaneous white adipose tissue depots was unchanged upon cold acclimation. Cold-induced skeletal muscle glucose uptake tended to increase upon cold acclimation, which was paralleled by increased basal GLUT4 localization in the sarcolemma, as assessed through muscle biopsies. Proximal skin temperature was increased and subjective responses to cold were slightly improved at the end of the acclimation period. These metabolic adaptations to prolonged exposure to mild cold may lead to improved glucose metabolism or prevent the development of obesity-associated insulin resistance and hyperglycemia.

Brown adipose tissue density measured by near-infrared time-resolved spectroscopy in Japanese, across a wide age range

“…This is the first study to demonstrate that the average ambient lower temperature, during the 4 and 6 weeks prior to the measurement day, under free-living situations, is associated with an elevation in the BAT-d. Laboratory studies showed that daily cold exposure (10°C to 17°C, 2 to 6h∕day), when dressed in unnaturally light clothing (t-shirt with underwear), for 10 days to 6 weeks, promoted BAT recruitment, 5,[8][9][10] and the results of these previous studies might provide a hint for the consideration of our result. Cohade et al 11 showed a rise in the monthly prevalence of BAT activity during the winter, but the rise was delayed by a few months, in relation to the beginning of a decrease in the AmT.…”

“…It has been reported that human BAT activity is related to cold-induced thermogenesis, 5 body weight, 5 and glucose tolerance. 6,7 Furthermore, daily cold exposure increased the BAT activity in healthy individuals, 5,8,9 obese individuals, 10 and patients with type 2 diabetes. 7 Thus, BAT is expected to be a potential tool to combat obesity and lifestyle-related diseases.…”

Mapping of human brown adipose tissue in lean and obese young men

“…Chronic cold conditioning of human subjects also has been shown to increase BAT activity in several recent studies (27,28). These lines of evidence have led some to postulate the energetic consequences of browning the entire WAT depot, including both visceral and subcutaneous fat (29).…”

Thermoneutrality, Mice, and Cancer: A Heated Opinion

“…Changes in fat tissue also accompany cold stress. In general, BAT increases activity and volume with cold stress [10,[34][35][36][37], and recently it has been recognized that cells in white adipose tissue (WAT) can be converted to a brown phenotype by cold exposure [38] (reviewed by [39]). Smith et al have recently visualized significant differences in BAT in mice at ST and TT showing that the lipid to water ratio in BAT is reduced in colder temperatures in accord with its role in thermogenesis [40].…”