Brown adipose tissue is involved in the seasonal variation of cold-induced thermogenesis in humans

Abstract

Brown adipose tissue (BAT) contributes to whole-body energy expenditure (EE), especially cold-induced thermogenesis (CIT), in humans. Although it is known that EE and CIT vary seasonally, their relationship with BAT has not been investigated. In the present study, we examined the impact of BAT on seasonal variations of EE/CIT and thermal responses to cold exposure in a randomized crossover design. Forty-five healthy male volunteers participated, and their BAT was assessed by positron emission tomography and computed tomography. CIT, the difference of EE at 27ºC and after 2-h cold exposure at 19ºC, significantly increased in winter compared to summer, being greater in subjects with metabolically active BAT (High BAT, 185.6 kcal/d, 18.3 kcal/d, P<0.001) than those without (Low BAT, 90.6 kcal/d, -46.5 kcal/d, P<0.05). Multivariate regression analysis revealed a significant interaction effect between season and BAT on CIT (P<0.001). The cold-induced drop of tympanic temperature (T) and skin temperature (T) in the forehead region and in the supraclavicular region close to BAT deposits were smaller in the High BAT group than in the Low BAT group in winter but not in summer. In contrast, the drop of Tin the subclavicular and peripheral regions distant from BAT was similar in the two groups in both seasons. In conclusion, CIT increased from summer to winter in a BAT-dependent manner, paralleling cold-induced changes in T/T, indicating a role of BAT in seasonal changes in the thermogenic and thermal responses to cold exposure in humans.

Brown adipose tissue, energy expenditure, and biomarkers of cardio‐metabolic health among the Yakut (Sakha) of northeastern Siberia

“…Recent research reports that the change in skin temperature of the supraclavicular area (ΔSCV) after a cooling condition can act as an indirect biomarker of BAT thermogenesis (Boon et al, ; Chondronikola et al, ; Salem et al, ; van der Lans et al, ; Yoneshiro et al, ). In response to cold stress, BAT deposits within the neck are activated by norepinephrine, which warms the skin above the clavicle.…”

“…In response to cold stress, BAT deposits within the neck are activated by norepinephrine, which warms the skin above the clavicle. Adults with active supraclavicular BAT exhibit either a minimal decline or an increase in skin temperature—ranging between −0.9°C and + 0.3°C—depending on the time length and severity of cooling condition (Boon et al, ; Chondronikola et al, ; Salem et al, ; van der Lans et al, ; Yoneshiro et al, ). In comparison, adults without detectable supraclavicular BAT experience a decline in skin temperature of around −1.5°C in this area (Chondronikola et al, ; Yoneshiro et al, ).…”

A systems perspective on brown adipogenesis and metabolic activation

“…). Numerous studies showed that the effects of chronic cold exposure are compelling and significantly improve systemic metabolic homeostasis, including insulin sensitivity as well as glucose and lipid profiles . Nevertheless, results of adult human‐based studies revealed important discrepancies, perhaps due to varying study conditions and experimental designs .…”

The Mediating Role of Brown Fat and Skeletal Muscle Measured by 18F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults

“…In addition to the peripheral tissues, the temperature of the brain is an input into the thermoregulatory system . One of the hypotheses explaining why human BAT is placed in the cervical and supraclavicular zone is that, as a thermogenic tissue, its main function is to regulate the temperature of the blood going to the brain . Several studies have shown that human BAT activation is related to an increase in the blood flow in BAT .…”