Brown Adipose Tissue and Skeletal Muscle 18F-FDG Activity After a Personalized Cold Exposure Is Not Associated With Cold-Induced Thermogenesis and Nutrient Oxidation Rates in Young Healthy Adults

Abstract Background Accumulating evidence links brown adipose tissue (BAT) to increased cold-induced energy expenditure (CIEE) and regulation of lipid metabolism in humans. BAT has also been proposed as a novel source for biologically active lipid mediators including polyunsaturated fatty acids (PUFAs) and oxylipins. However, little is known about cold-mediated differences in energy expenditure and various lipid species between individuals with detectable BAT positive (BATpos) and those without BAT negative (BATneg). Methods Here we investigated a unique cohort of matched BATpos and BATneg individuals identified by 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography ([18F]-FDG PET/CT). BAT function, CIEE, and circulating oxylipins, were analyzed before and after short-term cold exposure using [18F]-FDG PET/CT, indirect calorimetry, and high-resolution mass spectrometry, respectively. Results We found that active BAT is the major determinant of CIEE since only BATpos individuals experienced significantly increased energy expenditure in response to cold. A single bout of moderate cold exposure resulted in the dissipation of an additional 20 kcal excess energy in BATpos but not in BATneg individuals. The presence of BAT was associated with a unique systemic PUFA and oxylipin profile characterized by increased levels of anti-inflammatory omega-3 fatty acids as well as cytochrome P450 products but decreased concentrations of some proinflammatory hydroxyeicosatetraenoic acids when compared with BATneg individuals. Notably, cold exposure raised circulating levels of various lipids, including the recently identified BAT-derived circulating factors (BATokines) DiHOME and 12-HEPE, only in BATpos individuals. Conclusions In summary, our data emphasize that BAT in humans is a major contributor toward cold-mediated energy dissipation and a critical organ in the regulation of the systemic lipid pool.

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Type 2 iodothyronine deiodinase is upregulated in rat slow- and fast-twitch skeletal muscle during cold exposure

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00637.2013 ◽

2014 ◽

Vol 307 (11) ◽

pp. E1020-E1029 ◽

Cited By ~ 15

Author(s):

Ruy A. Louzada ◽

Maria C. S. Santos ◽

João Paulo A. Cavalcanti-de-Albuquerque ◽

Igor F. Rangel ◽

Andrea C. F. Ferreira ◽

...

Keyword(s):

Skeletal Muscle ◽

Adipose Tissue ◽

Brown Adipose Tissue ◽

Cold Acclimation ◽

Soleus Muscle ◽

Cold Exposure ◽

Skeletal Muscles ◽

Nonshivering Thermogenesis ◽

Brown Adipose

During cold acclimation, shivering is progressively replaced by nonshivering thermogenesis. Brown adipose tissue (BAT) and skeletal muscle are relevant for nonshivering thermogenesis, which depends largely on thyroid hormone. Since the skeletal muscle fibers progressively adapt to cold exposure through poorly defined mechanisms, our intent was to determine whether skeletal muscle type 2 deiodinase (D2) induction could be implicated in the long-term skeletal muscle cold acclimation. We demonstrate that in the red oxidative soleus muscle, D2 activity increased 2.3-fold after 3 days at 4°C together with the brown adipose tissue D2 activity, which increased 10-fold. Soleus muscle and BAT D2 activities returned to the control levels after 10 days of cold exposure, when an increase of 2.8-fold in D2 activity was detected in white glycolytic gastrocnemius but not in red oxidative gastrocnemius fibers. Propranolol did not prevent muscle D2 induction, but it impaired the decrease of D2 in BAT and soleus after 10 days at 4°C. Cold exposure is accompanied by increased oxygen consumption, UCP3, and PGC-1α genes expression in skeletal muscles, which were partialy prevented by propranolol in soleus and gastrocnemius. Serum total and free T3 is increased during cold exposure in rats, even after 10 days, when BAT D2 is already normalized, suggesting that skeletal muscle D2 activity contributes significantly to circulating T3 under this adaptive condition. In conclusion, cold exposure is accompanied by concerted changes in the metabolism of BAT and oxidative and glycolytic skeletal muscles that are paralleled by type 2 deiodinase activation.

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Combining 123I-Metaiodobenzylguanidine SPECT/CT and 18F-FDG PET/CT for the Assessment of Brown Adipose Tissue Activity in Humans During Cold Exposure

Journal of Nuclear Medicine ◽

10.2967/jnumed.112.111849 ◽

2013 ◽

Vol 54 (2) ◽

pp. 208-212 ◽

Cited By ~ 34

Author(s):

W. M. Admiraal ◽

F. Holleman ◽

L. Bahler ◽

M. R. Soeters ◽

J. B. Hoekstra ◽

...

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Cold Exposure ◽

Fdg Pet ◽

Brown Adipose ◽

Pet Ct ◽

18F Fdg ◽

Brown Adipose Tissue Activity ◽

Fdg Pet Ct

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Changes in electrocardiogram parameters during acute nonshivering cold exposure and associations with brown adipose tissue activity, plasma catecholamine levels, and brachial blood pressure in healthy adults

Physiological Reports ◽

10.14814/phy2.14718 ◽

2021 ◽

Vol 9 (3) ◽

Author(s):

Juho R. H. Raiko ◽

Teemu Saari ◽

Janne Orava ◽

Nina Savisto ◽

Riitta Parkkola ◽

...

Keyword(s):

Blood Pressure ◽

Adipose Tissue ◽

Brown Adipose Tissue ◽

Cold Exposure ◽

Healthy Adults ◽

Plasma Catecholamine ◽

Brachial Blood Pressure ◽

Brown Adipose ◽

Brown Adipose Tissue Activity ◽

Catecholamine Levels

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Preparation methods prior to PET/CT scanning that decrease uptake of 18F-FDG by myocardium, brown adipose tissue, and skeletal muscle

Acta Radiologica ◽

10.1177/0284185116633917 ◽

2016 ◽

Vol 58 (1) ◽

pp. 10-18 ◽

Cited By ~ 10

Author(s):

Dan Shao ◽

Xu-Wei Tian ◽

Qiang Gao ◽

Chang-Hong Liang ◽

Shu-Xia Wang

Keyword(s):

Skeletal Muscle ◽

Adipose Tissue ◽

Brown Adipose Tissue ◽

Ct Scanning ◽

High Fat ◽

Fdg Uptake ◽

Brown Adipose ◽

Pet Ct ◽

Low Carbohydrate ◽

18F Fdg

Background The hypermetabolic environment of the myocardium, brown adipose tissue (BAT), and muscle will have an effect on the diagnostic accuracy of 18F-fluorodeoxyglucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT). A low carbohydrate, high fat, and protein-permitted diet before PET/CT scanning can reduce the degree of 18F-FDG uptake by the myocardium, brown adipose tissue, and skeletal muscle. Purpose To determine the effect of a low carbohydrate, high fat and protein-permitted diet on 18F-FDG uptake by myocardium, BAT, and muscle during PET/CT. Material and Methods A total of 126 patients who adhered to two meals before PET/CT scanning (that were prepared using a low carbohydrate, high fat, and protein-permitted diet), i.e. the diet group, were compared with 126 patients who fasted for at least 12 h prior to scanning (i.e. the fasting group). The degree of 18F-FDG uptake within the myocardium, BAT, and muscle were stratified into four grades (range, 0–3) with 0 for negligible uptake, and 3 for intense uptake. Correlations between the diet and fasting groups with respect to degree of 18F-FDG uptake within the myocardium, BAT, and muscle were analyzed. Results The degree of 18F-FDG uptake within the myocardium, BAT, and muscle in the diet group was significantly lower compared with the 18F-FDG uptake within myocardium, BAT, and muscle in the fasting group ( P < 0.001, P = 0.001, P < 0.001). Conclusion A low carbohydrate/high fat diet before 18F-FDG injection can suppress uptake of 18F-FDG within the myocardium, BAT, and skeletal muscle.

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Thyroid function is not associated with brown adipose tissue volume and 18F-Fluorodeoxyglucose uptake in young euthyroid adults

Acta Endocrinologica ◽

10.1530/eje-21-0192 ◽

2021 ◽

Author(s):

Elisa Merchán Ramírez ◽

Guillermo Sanchez-Delgado ◽

Cristina Arrizabalaga-Arriazu ◽

Borja Martinez-Tellez ◽

Andrea Mendez-Gutierrez ◽

...

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Thyroid Function ◽

Cold Exposure ◽

Thyroid Stimulating Hormone ◽

Cross Sectional ◽

Fdg Uptake ◽

18F Fluorodeoxyglucose ◽

Brown Adipose ◽

18F Fdg

Purpose: Thyroid hormones (THs) are important mediators of brown adipose tissue (BAT) differentiation. However, the association of TH concentrations with human BAT is unclear. The present work examines the associations between circulating thyroid-stimulating hormone (TSH) and THs concentrations (i.e. free tri-iodothyronine, FT3, and free thyroxine, FT4), under thermoneutral [22-23ºC] and cold-induced conditions, and BAT volume, 18F-fluorodeoxyglucose (18F-FDG) uptake and mean radiodensity. Methods: A total of 106 young healthy, euthyroid adults (34 men/72 women; 22.0 ± 2.1 years old; 24.9 ± 4.6 kg/m2) participated in this cross-sectional study. BAT volume, 18F-FDG uptake and mean radiodensity were assessed after 2 h of personalized (i.e., contemplating each individual's shivering threshold) cold exposure via positron emission tomography/computerized tomography (PET/CT) static scanning. TSH and THs levels were determined before (thermoneutral) and 1 h after the cold exposure. Results: Cold exposure increased circulating FT4 (P=0.038) and reduced of TSH levels (P≤0.001). Conversely, the FT3 serum concentration was not modified by cold exposure (P=0.435). No associations were found between the TSH and THs thermoneutral (all P>0.289) or cold-induced levels (all P>0.067) and BAT volume,18F-FDG uptake and mean radiodensity. These findings were independent of sex and body mass index. Conclusions: Thyroid function is modulated by cold exposure, yet it is not associated with BAT volume or glucose metabolism assessed after 2h of cold exposure in young healthy, euthyroid adults.

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