1
|
Carpentier AC. Tracers and Imaging of Fatty Acid and Energy Metabolism of Human Adipose Tissues. Physiology (Bethesda) 2024; 39:0. [PMID: 38113392 DOI: 10.1152/physiol.00012.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 11/22/2023] [Accepted: 12/19/2023] [Indexed: 12/21/2023] Open
Abstract
White adipose tissue and brown adipose tissue (WAT and BAT) regulate fatty acid metabolism and control lipid fluxes to other organs. Dysfunction of these key metabolic processes contributes to organ insulin resistance and inflammation leading to chronic diseases such as type 2 diabetes, metabolic dysfunction-associated steatohepatitis, and cardiovascular diseases. Metabolic tracers combined with molecular imaging methods are powerful tools for the investigation of these pathogenic mechanisms. Herein, I review some of the positron emission tomography and magnetic resonance imaging methods combined with stable isotopic metabolic tracers to investigate fatty acid and energy metabolism, focusing on human WAT and BAT metabolism. I will discuss the complementary strengths offered by these methods for human investigations and current gaps in the field.
Collapse
Affiliation(s)
- André C Carpentier
- Department of Medicine, Division of Endocrinology, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| |
Collapse
|
2
|
Wang H, Ülgen M, Trajkovski M. Importance of temperature on immuno-metabolic regulation and cancer progression. FEBS J 2024; 291:832-845. [PMID: 36152006 DOI: 10.1111/febs.16632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 09/01/2022] [Accepted: 09/20/2022] [Indexed: 11/29/2022]
Abstract
Cancer immunotherapies emerge as promising strategies for restricting tumour growth. The tumour microenvironment (TME) has a major impact on the anti-tumour immune response and on the efficacy of the immunotherapies. Recent studies have linked changes in the ambient temperature with particular immuno-metabolic reprogramming and anti-cancer immune response in laboratory animals. Here, we describe the energetic balance of the organism during change in temperature, and link this to the immune alterations that could be of relevance for cancer, as well as for other human diseases. We highlight the contribution of the gut microbiota in modifying this interaction. We describe the overall metabolic response and underlying mechanisms of tumourigenesis in mouse models at varying ambient temperatures and shed light on their potential importance in developing therapeutics against cancer.
Collapse
Affiliation(s)
- Haiping Wang
- Department of Cell Physiology and Metabolism, Faculty of Medicine, Centre Medical Universitaire (CMU), University of Geneva, Geneva, Switzerland
- Faculty of Medicine, Diabetes Center, University of Geneva, Geneva, Switzerland
| | - Melis Ülgen
- Department of Cell Physiology and Metabolism, Faculty of Medicine, Centre Medical Universitaire (CMU), University of Geneva, Geneva, Switzerland
- Faculty of Medicine, Diabetes Center, University of Geneva, Geneva, Switzerland
| | - Mirko Trajkovski
- Department of Cell Physiology and Metabolism, Faculty of Medicine, Centre Medical Universitaire (CMU), University of Geneva, Geneva, Switzerland
- Faculty of Medicine, Diabetes Center, University of Geneva, Geneva, Switzerland
| |
Collapse
|
3
|
Wu B, Cheng C, Qi Y, Zhou H, Peng H, Wan Q, Liu X, Zheng H, Zhang H, Zou C. Automatic segmentation of human supraclavicular adipose tissue using high-resolution T2-weighted magnetic resonance imaging. MAGMA (NEW YORK, N.Y.) 2023; 36:641-649. [PMID: 36538249 DOI: 10.1007/s10334-022-01056-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 12/07/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
OBJECTIVE To achieve efficient segmentation of human supraclavicular adipose tissue (sclavAT) using high-resolution T2-weighted magnetic resonance images. METHODS High-resolution 1.0 mm isotropic 3D T2-weighted images covering human supraclavicular area were acquired in transverse or coronary plane from 29 volunteers using a 3.0 T MRI scanner. There were typically 144/288 slices for the transverse/coronary scans for each subject, which amounts to a total of 6816 images in 29 volunteers. A U-NET network was trained to segment the supraclavicular adipose tissue (sclavAT). The performance of the automatic segmentation method was evaluated by comparing the output results with the manual labels using the quantitative indices of dice similarity coefficient (DSC), precision rate (PR), and recall rate (RR). The auto-segmented images were used to calculate the sclavAT volumes and registered to the MR fat fraction (FF) images to quantify the fat component of the sclavAT area. The relationship between body mass index (BMI), the volume and FF of sclavAT area was evaluated for all subjects. RESULTS The DSC, PR and RR of the automatic sclavAT segmentation method on the testing datasets were 0.920 ± 0.048, 0.915 ± 0.070 and 0.930 ± 0.058. The volume and the mean FF of sclavAT were both found to be strongly correlated to BMI, with the correlation coefficient of 0.703 and 0.625 (p < 0.05), respectively. The averaged computation time of the automatic segmentation method was approximately 0.06 s per slice, compared to more than 5 min for manual labeling. CONCLUSION The present study demonstrates that the proposed automatic segmentation method using U-Net network is able to identify human sclavAT efficiently and accurately.
Collapse
Affiliation(s)
- Bingxia Wu
- School of Information Engineering, Wuhan University of Technology, Wuhan, China
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen, 518055, China
| | - Chuanli Cheng
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen, 518055, China
- Imaging Research Institute of Innovative Medical Equipment, Shenzhen, China
| | - Yulong Qi
- Radiology Department, Peking University Shenzhen Hospital, Shenzhen, China
| | - Hongyu Zhou
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen, 518055, China
| | - Hao Peng
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen, 518055, China
| | - Qian Wan
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen, 518055, China
| | - Xin Liu
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen, 518055, China
| | - Hairong Zheng
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen, 518055, China
| | - Huimao Zhang
- Radiology Department, Bethune First Hospital of Jilin University, Changchun, China
| | - Chao Zou
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen, 518055, China.
- Imaging Research Institute of Innovative Medical Equipment, Shenzhen, China.
| |
Collapse
|
4
|
Bao C, Chen O, Sheng H, Zhang J, Luo Y, Hayes BW, Liang H, Liedtke W, Ji RR, Abraham SN. A mast cell-thermoregulatory neuron circuit axis regulates hypothermia in anaphylaxis. Sci Immunol 2023; 8:eadc9417. [PMID: 36930731 DOI: 10.1126/sciimmunol.adc9417] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
IgE-mediated anaphylaxis is an acute life-threatening systemic reaction to allergens, including certain foods and venoms. Anaphylaxis is triggered when blood-borne allergens activate IgE-bound perivascular mast cells (MCs) throughout the body, causing an extensive systemic release of MC mediators. Through precipitating vasodilatation and vascular leakage, these mediators are believed to trigger a sharp drop in blood pressure in humans and in core body temperature in animals. We report that the IgE/MC-mediated drop in body temperature in mice associated with anaphylaxis also requires the body's thermoregulatory neural circuit. This circuit is activated when granule-borne chymase from MCs is deposited on proximal TRPV1+ sensory neurons and stimulates them via protease-activated receptor-1. This triggers the activation of the body's thermoregulatory neural network, which rapidly attenuates brown adipose tissue thermogenesis to cause hypothermia. Mice deficient in either chymase or TRPV1 exhibited limited IgE-mediated anaphylaxis, and, in wild-type mice, anaphylaxis could be recapitulated simply by systemically activating TRPV1+ sensory neurons. Thus, in addition to their well-known effects on the vasculature, MC products, especially chymase, promote IgE-mediated anaphylaxis by activating the thermoregulatory neural circuit.
Collapse
Affiliation(s)
- Chunjing Bao
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ouyang Chen
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Huaxin Sheng
- Multidisciplinary Neuroprotection Laboratories, Center of Perioperative Organ Protection, Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Jeffrey Zhang
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| | - Yikai Luo
- Graduate Program in Quantitative and Computational Biosciences, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Byron W Hayes
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| | - Han Liang
- Graduate Program in Quantitative and Computational Biosciences, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Department of Systems Biology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Wolfgang Liedtke
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York NY 10010, USA
| | - Ru-Rong Ji
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Soman N Abraham
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham NC 27710, USA
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore
| |
Collapse
|
5
|
Abstract
Brown adipose tissue (BAT) displays the unique capacity to generate heat through uncoupled oxidative phosphorylation that makes it a very attractive therapeutic target for cardiometabolic diseases. Here, we review BAT cellular metabolism, its regulation by the central nervous and endocrine systems and circulating metabolites, the plausible roles of this tissue in human thermoregulation, energy balance, and cardiometabolic disorders, and the current knowledge on its pharmacological stimulation in humans. The current definition and measurement of BAT in human studies relies almost exclusively on BAT glucose uptake from positron emission tomography with 18F-fluorodeoxiglucose, which can be dissociated from BAT thermogenic activity, as for example in insulin-resistant states. The most important energy substrate for BAT thermogenesis is its intracellular fatty acid content mobilized from sympathetic stimulation of intracellular triglyceride lipolysis. This lipolytic BAT response is intertwined with that of white adipose (WAT) and other metabolic tissues, and cannot be independently stimulated with the drugs tested thus far. BAT is an interesting and biologically plausible target that has yet to be fully and selectively activated to increase the body's thermogenic response and shift energy balance. The field of human BAT research is in need of methods able to directly, specifically, and reliably measure BAT thermogenic capacity while also tracking the related thermogenic responses in WAT and other tissues. Until this is achieved, uncertainty will remain about the role played by this fascinating tissue in human cardiometabolic diseases.
Collapse
Affiliation(s)
- André C Carpentier
- Correspondence: André C. Carpentier, MD, Division of Endocrinology, Faculty of Medicine, University of Sherbrooke, 3001, 12th Ave N, Sherbrooke, Quebec, J1H 5N4, Canada.
| | - Denis P Blondin
- Division of Neurology, Department of Medicine, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, J1H 5N4, Canada
| | | | - Denis Richard
- Centre de recherche de l’Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Quebec City, Quebec, G1V 4G5, Canada
| |
Collapse
|
6
|
High-fructose feeding suppresses cold-stimulated brown adipose tissue glucose uptake independently of changes in thermogenesis and the gut microbiome. Cell Rep Med 2022; 3:100742. [PMID: 36130480 PMCID: PMC9512695 DOI: 10.1016/j.xcrm.2022.100742] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 06/14/2022] [Accepted: 08/23/2022] [Indexed: 12/30/2022]
Abstract
Diets rich in added sugars are associated with metabolic diseases, and studies have shown a link between these pathologies and changes in the microbiome. Given the reported associations in animal models between the microbiome and brown adipose tissue (BAT) function, and the alterations in the microbiome induced by high-glucose or high-fructose diets, we investigated the potential causal link between high-glucose or -fructose diets and BAT dysfunction in humans. Primary outcomes are changes in BAT cold-induced thermogenesis and the fecal microbiome (clinicaltrials.gov, NCT03188835). We show that BAT glucose uptake, but not thermogenesis, is impaired by a high-fructose but not high-glucose diet, in the absence of changes in the gastrointestinal microbiome. We conclude that decreased BAT glucose metabolism occurs earlier than other pathophysiological abnormalities during fructose overconsumption in humans. This is a potential confounding factor for studies relying on 18F-FDG to assess BAT thermogenesis. Fructose overfeeding decreases brown adipose tissue glucose metabolism These changes occur independently of oxidative metabolism No change is observed with glucose overfeeding The gut microbiome is not affected by fructose/glucose overfeeding
Collapse
|
7
|
Pinto YO, Festuccia WTL, Magdalon J. The involvement of the adrenergic nervous system in activating human brown adipose tissue and browning. Hormones (Athens) 2022; 21:195-208. [PMID: 35247188 DOI: 10.1007/s42000-022-00361-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 02/24/2022] [Indexed: 11/04/2022]
Abstract
Obesity is a chronic condition of multifactorial etiology characterized by excessive body fat due to a calorie intake higher than energy expenditure. Given the intrinsic limitations of surgical interventions and the difficulties associated with lifestyle changes, pharmacological manipulation is currently one of the main therapies for metabolic diseases. Approaches aiming to promote energy expenditure through induction of thermogenesis have been explored and, in this context, brown adipose tissue (BAT) activation and browning have been shown to be promising strategies. Although such processes are physiologically stimulated by the sympathetic nervous system, not all situations that are known to increase adrenergic signaling promote a concomitant increase in BAT activation or browning in humans. Thus, a better understanding of factors involved in the thermogenesis attributed to these tissues is needed to enable the development of future therapies against obesity. Herein we carry out a critical review of original articles in humans under conditions previously known to trigger adrenergic responses-namely, cold, catecholamine-secreting tumor (pheochromocytoma and paraganglioma), burn injury, and adrenergic agonists-and discuss which of them are associated with increased BAT activation and browning. BAT is clearly stimulated in individuals exposed to cold or treated with high doses of the β3-adrenergic agonist mirabegron, whereas browning is certainly induced in patients after burn injury or with pheochromocytoma, as well as in individuals treated with β3-adrenergic agonist mirabegron for at least 10 weeks. Given the potential effect of increasing energy expenditure, adrenergic stimuli are promising strategies in the treatment of metabolic diseases.
Collapse
Affiliation(s)
- Yolanda Oliveira Pinto
- Faculdade Israelita de Ciências da Saúde Albert Einstein, Hospital Israelita Albert Einstein, Sao Paulo, SP, Brazil
| | | | - Juliana Magdalon
- Faculdade Israelita de Ciências da Saúde Albert Einstein, Hospital Israelita Albert Einstein, Sao Paulo, SP, Brazil.
| |
Collapse
|
8
|
Ahmed BA, Varah N, Ong FJ, Blondin DP, Gunn E, Konyer NB, Singh NP, Noseworthy MD, Haman F, Carpentier AC, Punthakee Z, Steinberg GR, Morrison KM. Impaired Cold-Stimulated Supraclavicular Brown Adipose Tissue Activity in Young Boys With Obesity. Diabetes 2022; 71:1193-1204. [PMID: 35293989 DOI: 10.2337/db21-0799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 02/28/2022] [Indexed: 11/13/2022]
Abstract
Childhood obesity is a growing worldwide problem. In adults, lower cold-induced brown adipose tissue (BAT) activity is linked to obesity and metabolic dysfunction; this relationship remains uncertain in children. In this cross-sectional study, we compared cold-induced supraclavicular (SCV) BAT activity (percent change in proton density fat fraction [PDFF]) within the SCV region after 1 h of whole-body cold exposure (18°C), using MRI in 26 boys aged 8-10 years: 13 with normal BMI and 13 with overweight/obesity. Anthropometry, body composition, hepatic fat, visceral adipose tissue (VAT), and pre- and postcold PDFF of the subcutaneous adipose tissue (SAT) in the posterior neck region and the abdomen were measured. Boys with overweight/obesity had lower cold-induced percent decline in SCV PDFF compared with those with normal BMI (1.6 ± 0.8 vs. 4.7 ± 1.2%, P = 0.044). SCV PDFF declined significantly in boys with normal BMI (2.7 ± 0.7%, P = 0.003) but not in boys with overweight/obesity (1.1 ± 0.5%, P = 0.053). No cold-induced changes in the PDFF of either neck SAT (-0.89 ± 0.7%, P = 0.250, vs. 0.37 ± 0.3%, P = 0.230) or abdominal SAT (-0.39 ± 0.5%, P = 0.409, and 0.25 ± 0.2%, P = 0.139, for normal BMI and overweight/obesity groups, respectively) were seen. The cold-induced percent decline in SCV PDFF was inversely related to BMI (r = -0.39, P = 0.047), waist circumference (r = -0.48, P = 0.014), and VAT (r = -0.47, P = 0.014). Thus, in young boys, as in adults, BAT activity is lower in those with overweight/obesity, suggesting that restoring activity may be important for improving metabolic health.
Collapse
Affiliation(s)
- Basma A Ahmed
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Nina Varah
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| | - Frank J Ong
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| | - Denis P Blondin
- Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Elizabeth Gunn
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| | - Norman B Konyer
- Imaging Research Centre, St. Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
| | - Nina P Singh
- Department of Radiology, McMaster University, Hamilton, Ontario, Canada
| | - Michael D Noseworthy
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
- Imaging Research Centre, St. Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
- Department of Radiology, McMaster University, Hamilton, Ontario, Canada
- Department of Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, Canada
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
| | - Francois Haman
- Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada
| | - Andre C Carpentier
- Division of Endocrinology, Department of Medicine, Faculty of Medicine and Health Sciences, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Zubin Punthakee
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Gregory R Steinberg
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Katherine M Morrison
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
9
|
Niclou A, Ocobock C. Weather permitting: Increased seasonal efficiency of nonshivering thermogenesis through brown adipose tissue activation in the winter. Am J Hum Biol 2021; 34:e23716. [PMID: 34942026 DOI: 10.1002/ajhb.23716] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 12/10/2021] [Accepted: 12/11/2021] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVES We investigated seasonal changes in brown adipose tissue (BAT) activation and metabolism in a temperate-climate Albany, NY population. METHODS Data were collected among 58 participants (21 males, 37 females, ages: 18-51) in the summer and 59 participants (23 males, 36 females, ages: 18-63) in the winter in Albany, New York. BAT activity was inferred by comparing metabolic rate, heat dissipation in the supraclavicular area, and respiratory quotient at room temperature and cold exposure. Seasonal variation in BAT was determined by comparing these measurements from summer and winter. RESULTS At mild cold exposure, heat dissipation of the supraclavicular area was significantly greater in the winter compared to summer (p < .001); however, no significant differences were found between seasons in metabolic rate measurements. This suggests BAT activation may be metabolically more efficient in the winter, due to prolonged lower seasonal temperatures relative to summer. Respiratory quotient significantly increased upon mild cold exposure in the winter compared to summer (p < .001). While carbohydrate utilization increased in the winter, fat remained the primary metabolic substrate for BAT activity across both seasons. CONCLUSION The seasonal variations in the effects of nonshivering thermogenesis on metabolic rate and substrate metabolism suggest a buffering of energy expenditure and an increased use of glucose as fuel by BAT as a result of acclimatization to cold in the winter. These findings point towards a potential role of BAT in human whole-body mediated glucose disposal and cold adaptation.
Collapse
Affiliation(s)
- Alexandra Niclou
- Department of Anthropology, University of Notre Dame, Notre Dame, Indiana, USA
| | - Cara Ocobock
- Department of Anthropology, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, Institute for Educational Initiatives, University of Notre Dame, Notre Dame, Indiana, USA
| |
Collapse
|
10
|
Flanagan EW, Altazan AD, Carmichael OT, Hu HH, Redman LM. Practical application of in vivo MRI-based brown adipose tissue measurements in infants. Obesity (Silver Spring) 2021; 29:1676-1683. [PMID: 34553508 PMCID: PMC9115839 DOI: 10.1002/oby.23237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 05/17/2021] [Accepted: 05/19/2021] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The role of brown adipose tissue (BAT) in infant metabolism remains poorly understood, primarily because of the inherent limitation of positron emission tomography/computed tomography imaging to measure BAT, which is not suitable for infants. The aims of this method development study were to assess the feasibility, intra-rater reliability, interscan repeatability, and physiological relevance of measuring BAT in infants using magnetic resonance imaging (MRI). METHODS A total of 10 nonsedated infants (mean age, 22.6 [1.3] days old) completed two 3-T MRI exams using chemical-shift-encoded water-fat scans 6.2 (2.8) days apart. Candidate BAT voxels in the supraclavicular region were identified based on fat signal fraction (FSF). The volumes of BAT depots were manually traced, and FSF was calculated. Whole-body fat mass was determined using dual-energy x-ray absorptiometry. RESULTS Images were successfully obtained from 19 of 20 (95%) attempted scans. The mean BAT volume was 5.41 (SD 1.1) cm3 , and the mean FSF was 16.41% (SD 3.3%). Intra-rater analysis showed good reliability with no systemic bias (proportional bias for volume: p = 0.19; FSF: p = 0.30). Test-retest for interscan repeatability was good (intraclass correlation coefficients for volume: 0.92, p = 0.001 and intraclass correlation coefficients for FSF: 0.93, p < 0.001). FSF was inversely related to fat-free mass (r = -0.69, p = 0.03). CONCLUSIONS This method development study supports the use of MRI to obtain reliable and quantitative measurements of BAT volume in infants.
Collapse
Affiliation(s)
- Emily W Flanagan
- Pennington Biomedical Research Center, Baton Rouge, Louisana, USA
| | - Abby D Altazan
- Pennington Biomedical Research Center, Baton Rouge, Louisana, USA
| | | | - Houchun H Hu
- Hyperfine Research, Inc., Guilford, Connecticut, USA
| | - Leanne M Redman
- Pennington Biomedical Research Center, Baton Rouge, Louisana, USA
| |
Collapse
|
11
|
Ahmed BA, Ong FJ, Barra NG, Blondin DP, Gunn E, Oreskovich SM, Szamosi JC, Syed SA, Hutchings EK, Konyer NB, Singh NP, Yabut JM, Desjardins EM, Anhê FF, Foley KP, Holloway AC, Noseworthy MD, Haman F, Carpentier AC, Surette MG, Schertzer JD, Punthakee Z, Steinberg GR, Morrison KM. Lower brown adipose tissue activity is associated with non-alcoholic fatty liver disease but not changes in the gut microbiota. Cell Rep Med 2021; 2:100397. [PMID: 34622234 PMCID: PMC8484690 DOI: 10.1016/j.xcrm.2021.100397] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 06/25/2021] [Accepted: 08/18/2021] [Indexed: 12/18/2022]
Abstract
In rodents, lower brown adipose tissue (BAT) activity is associated with greater liver steatosis and changes in the gut microbiome. However, little is known about these relationships in humans. In adults (n = 60), we assessed hepatic fat and cold-stimulated BAT activity using magnetic resonance imaging and the gut microbiota with 16S sequencing. We transplanted gnotobiotic mice with feces from humans to assess the transferability of BAT activity through the microbiota. Individuals with NAFLD (n = 29) have lower BAT activity than those without, and BAT activity is inversely related to hepatic fat content. BAT activity is not related to the characteristics of the fecal microbiota and is not transmissible through fecal transplantation to mice. Thus, low BAT activity is associated with higher hepatic fat accumulation in human adults, but this does not appear to have been mediated through the gut microbiota.
Collapse
Affiliation(s)
- Basma A. Ahmed
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Frank J. Ong
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Pediatrics, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Nicole G. Barra
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Denis P. Blondin
- Faculty of Medicine and Health Sciences, Department of Medicine, Division of Neurology, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada
| | - Elizabeth Gunn
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Pediatrics, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Stephan M. Oreskovich
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Pediatrics, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Jake C. Szamosi
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON L8S 4L8, Canada
- Farncombe Metagenomics Facility, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Saad A. Syed
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Emily K. Hutchings
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Pediatrics, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Norman B. Konyer
- Imaging Research Centre, St. Joseph’s Healthcare, Hamilton, ON L8N 4A6, Canada
| | - Nina P. Singh
- Department of Radiology, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Julian M. Yabut
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Eric M. Desjardins
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Fernando F. Anhê
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Kevin P. Foley
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Alison C. Holloway
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Michael D. Noseworthy
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Imaging Research Centre, St. Joseph’s Healthcare, Hamilton, ON L8N 4A6, Canada
- Department of Radiology, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Electrical and Computer Engineering, McMaster University, Hamilton, ON L8S 4L8, Canada
- School of Biomedical Engineering, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Francois Haman
- Faculty of Health Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Andre C. Carpentier
- Division of Endocrinology, Department of Medicine, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada
| | - Michael G. Surette
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Jonathan D. Schertzer
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Zubin Punthakee
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Pediatrics, McMaster University, Hamilton, ON L8S 4L8, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Gregory R. Steinberg
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Katherine M. Morrison
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Pediatrics, McMaster University, Hamilton, ON L8S 4L8, Canada
| |
Collapse
|
12
|
Yang J, Zhang H, Parhat K, Xu H, Li M, Wang X, Ran C. Molecular Imaging of Brown Adipose Tissue Mass. Int J Mol Sci 2021; 22:ijms22179436. [PMID: 34502347 PMCID: PMC8431742 DOI: 10.3390/ijms22179436] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/26/2021] [Accepted: 08/26/2021] [Indexed: 12/28/2022] Open
Abstract
Brown adipose tissue (BAT), a uniquely thermogenic tissue that plays an important role in metabolism and energy expenditure, has recently become a revived target in the fight against metabolic diseases, such as obesity, diabetes, and non-alcoholic fatty liver disease (NAFLD). Different from white adipose tissue (WAT), the brown adipocytes have distinctive features including multilocular lipid droplets, a large number of mitochondria, and a high expression of uncoupling protein-1 (UCP-1), as well as abundant capillarity. These histologic characteristics provide an opportunity to differentiate BAT from WAT using imaging modalities, such as PET/CT, SPECT/CT, MRI, NIRF and Ultrasound. However, most of the reported imaging methods were BAT activation dependent, and the imaging signals could be affected by many factors, including environmental temperatures and the states of the sympathetic nervous system. Accurate BAT mass detection methods that are independent of temperature and hormone levels have the capacity to track the development and changes of BAT throughout the lifetime of mammals, and such methods could be very useful for the investigation of potential BAT-related therapies. In this review, we focus on molecular imaging modalities that can detect and quantify BAT mass. In addition, their detection mechanism and limitations will be discussed as well.
Collapse
Affiliation(s)
- Jing Yang
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China; (H.Z.); (K.P.); (H.X.); (M.L.); (X.W.)
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Room 2301, Building 149, Charlestown, Boston, MA 02129, USA
- Correspondence: (J.Y.); (C.R.)
| | - Haili Zhang
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China; (H.Z.); (K.P.); (H.X.); (M.L.); (X.W.)
| | - Kadirya Parhat
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China; (H.Z.); (K.P.); (H.X.); (M.L.); (X.W.)
| | - Hui Xu
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China; (H.Z.); (K.P.); (H.X.); (M.L.); (X.W.)
| | - Mingshuang Li
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China; (H.Z.); (K.P.); (H.X.); (M.L.); (X.W.)
| | - Xiangyu Wang
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China; (H.Z.); (K.P.); (H.X.); (M.L.); (X.W.)
| | - Chongzhao Ran
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Room 2301, Building 149, Charlestown, Boston, MA 02129, USA
- Correspondence: (J.Y.); (C.R.)
| |
Collapse
|
13
|
A physiological glucocorticoid rhythm is an important regulator of brown adipose tissue function. Mol Metab 2021; 47:101179. [PMID: 33548499 PMCID: PMC7907824 DOI: 10.1016/j.molmet.2021.101179] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/27/2021] [Accepted: 01/29/2021] [Indexed: 12/18/2022] Open
Abstract
Objective Brown adipose tissue (BAT) displays a strong circadian rhythm in metabolic activity, but it is unclear how this rhythm is regulated. As circulating levels of corticosterone coincide with the rhythm of triglyceride-derived fatty acid (FA) uptake by BAT, we investigated whether corticosterone regulates BAT circadian rhythm. Methods Corticosterone levels were flattened by implanting mice with subcutaneous corticosterone-releasing pellets, resulting in constant circulating corticosterone levels. Results Flattened corticosterone rhythm caused a complete loss of circadian rhythm in triglyceride-derived fatty acid uptake by BAT. This effect was independent of glucocorticoid receptor expression in (brown) adipocytes and was not caused by deregulation of clock gene expression or overexposure to glucocorticoids, but rather seemed mediated by reduced sympathetic innervation of BAT. In a mouse model of hyperlipidemia and metabolic syndrome, long-term experimental flattening of corticosterone − and thus rhythm in BAT function − resulted in adiposity. Conclusions This study highlights that a physiological rhythm in glucocorticoids is an important regulator of BAT function and essential for the maintenance of metabolic health. Flattening of corticosterone rhythm blunts circadian activity of brown adipose tissue. Disturbed corticosterone rhythm − rather than overexposure− is responsible for blunted brown adipose tissue activity. The metabolic effect of flattened corticosterone levels is independent of adipocyte glucocorticoid receptor expression. Long-term flattening of corticosterone levels results in increased adiposity in a female mouse model for metabolic syndrome.
Collapse
|
14
|
Sanchez-Delgado G, Alcantara JMA, Acosta FM, Martinez-Tellez B, Amaro-Gahete FJ, Merchan-Ramirez E, Löf M, Labayen I, Ravussin E, Ruiz JR. Energy Expenditure and Macronutrient Oxidation in Response to an Individualized Nonshivering Cooling Protocol. Obesity (Silver Spring) 2020; 28:2175-2183. [PMID: 32985119 DOI: 10.1002/oby.22972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 07/08/2020] [Accepted: 07/09/2020] [Indexed: 11/07/2022]
Abstract
OBJECTIVE This study aimed to describe the energy expenditure (EE) and macronutrient oxidation response to an individualized nonshivering cold exposure in young healthy adults. METHODS Two different groups of 44 (study 1: 22.1 [SD 2.1] years old, 25.6 [SD 5.2] kg/m2 , 34% men) and 13 young healthy adults (study 2: 25.6 [SD 3.0] years old, 23.6 [SD 2.4] kg/m2 , 54% men) participated in this study. Resting metabolic rate (RMR) and macronutrient oxidation rates were measured by indirect calorimetry under fasting conditions in a warm environment (for 30 minutes) and in mild cold conditions (for 65 minutes, with the individual wearing a water-perfused cooling vest set at an individualized temperature adjusted to the individual's shivering threshold). RESULTS In study 1, EE increased in the initial stage of cold exposure and remained stable for the whole cold exposure (P < 0.001). Mean cold-induced thermogenesis (9.56 ± 7.9 kcal/h) was 13.9% ± 11.6% of the RMR (range: -14.8% to 39.9% of the RMR). Carbohydrate oxidation decreased during the first 30 minutes of the cold exposure and later recovered up to the baseline values (P < 0.01) in parallel to opposite changes in fat oxidation (P < 0.01). Results were replicated in study 2. CONCLUSIONS A 1-hour mild cold exposure individually adjusted to elicit maximum nonshivering thermogenesis induces a very modest increase in EE and a shift of macronutrient oxidation that may underlie a shift in thermogenic tissue activity.
Collapse
Affiliation(s)
- Guillermo Sanchez-Delgado
- Promoting Fitness and Health Through Physical Activity Research Group, Sport and Health University Research Institute, Faculty of Sport Sciences, University of Granada, Granada, Spain
- Department of Physical Education and Sports, University of Granada, Granada, Spain
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA
| | - Juan M A Alcantara
- Promoting Fitness and Health Through Physical Activity Research Group, Sport and Health University Research Institute, Faculty of Sport Sciences, University of Granada, Granada, Spain
- Department of Physical Education and Sports, University of Granada, Granada, Spain
| | - Francisco M Acosta
- Promoting Fitness and Health Through Physical Activity Research Group, Sport and Health University Research Institute, Faculty of Sport Sciences, University of Granada, Granada, Spain
- Department of Physical Education and Sports, University of Granada, Granada, Spain
| | - Borja Martinez-Tellez
- Promoting Fitness and Health Through Physical Activity Research Group, Sport and Health University Research Institute, Faculty of Sport Sciences, University of Granada, Granada, Spain
- Department of Physical Education and Sports, University of Granada, Granada, Spain
- Division of Endocrinology, Department of Medicine, Leiden University Medical Center, Leiden University, Leiden, the Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Medicine, Leiden University Medical Center, Leiden University, Leiden, the Netherlands
| | - Francisco J Amaro-Gahete
- Promoting Fitness and Health Through Physical Activity Research Group, Sport and Health University Research Institute, Faculty of Sport Sciences, University of Granada, Granada, Spain
- Department of Physical Education and Sports, University of Granada, Granada, Spain
- Department of Medical Physiology, School of Medicine, University of Granada, Granada, Spain
| | - Elisa Merchan-Ramirez
- Promoting Fitness and Health Through Physical Activity Research Group, Sport and Health University Research Institute, Faculty of Sport Sciences, University of Granada, Granada, Spain
- Department of Physical Education and Sports, University of Granada, Granada, Spain
| | - Marie Löf
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
- Department of Health, Medicine Caring Sciences, Linköping University, Linköping, Sweden
| | - Idoia Labayen
- Institute for Innovation and Sustainable Development in Food Chain, Navarra's Health Research Institute, Department of Health Sciences, Public University of Navarra, Pamplona, Spain
| | - Eric Ravussin
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA
| | - Jonatan R Ruiz
- Promoting Fitness and Health Through Physical Activity Research Group, Sport and Health University Research Institute, Faculty of Sport Sciences, University of Granada, Granada, Spain
- Department of Physical Education and Sports, University of Granada, Granada, Spain
| |
Collapse
|
15
|
Functional characterization of human brown adipose tissue metabolism. Biochem J 2020; 477:1261-1286. [PMID: 32271883 DOI: 10.1042/bcj20190464] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/13/2020] [Accepted: 03/16/2020] [Indexed: 02/07/2023]
Abstract
Brown adipose tissue (BAT) has long been described according to its histological features as a multilocular, lipid-containing tissue, light brown in color, that is also responsive to the cold and found especially in hibernating mammals and human infants. Its presence in both hibernators and human infants, combined with its function as a heat-generating organ, raised many questions about its role in humans. Early characterizations of the tissue in humans focused on its progressive atrophy with age and its apparent importance for cold-exposed workers. However, the use of positron emission tomography (PET) with the glucose tracer [18F]fluorodeoxyglucose ([18F]FDG) made it possible to begin characterizing the possible function of BAT in adult humans, and whether it could play a role in the prevention or treatment of obesity and type 2 diabetes (T2D). This review focuses on the in vivo functional characterization of human BAT, the methodological approaches applied to examine these features and addresses critical gaps that remain in moving the field forward. Specifically, we describe the anatomical and biomolecular features of human BAT, the modalities and applications of non-invasive tools such as PET and magnetic resonance imaging coupled with spectroscopy (MRI/MRS) to study BAT morphology and function in vivo, and finally describe the functional characteristics of human BAT that have only been possible through the development and application of such tools.
Collapse
|
16
|
Saari TJ, Raiko J, U-Din M, Niemi T, Taittonen M, Laine J, Savisto N, Haaparanta-Solin M, Nuutila P, Virtanen KA. Basal and cold-induced fatty acid uptake of human brown adipose tissue is impaired in obesity. Sci Rep 2020; 10:14373. [PMID: 32873825 PMCID: PMC7463032 DOI: 10.1038/s41598-020-71197-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 07/20/2020] [Indexed: 11/17/2022] Open
Abstract
Fatty acids (FA) are important substrates for brown adipose tissue (BAT) metabolism, however, it remains unclear whether there exists a difference in FA metabolism of BAT between lean and obese healthy humans. In this study we evaluated supraclavicular BAT fatty acid uptake (FAU) along with blood perfusion in lean and obese subjects during cold exposure and at room temperature using positron emission tomography (PET)/computed tomography (CT). Additionally, tissue samples were taken from supraclavicular region (typical BAT region) from a subset of subjects to evaluate histological presence of BAT. Non-shivering cold stress elevated FAU and perfusion of BAT in lean, but not in obese subjects. Lean subjects had greater FAU in BAT compared to obese subjects during cold exposure and interestingly also at room temperature. The higher BAT FAU was related to younger age and several indicators of superior systemic metabolic health. The subjects who manifested BAT histologically had several folds higher BAT FAU compared to subjects with no such histological manifestation. Together, obese subjects have less active tissue in supraclavicular region both in basal and cold-activated state and the FA metabolism of BAT is blunted in obesity.
Collapse
Affiliation(s)
- T J Saari
- Turku PET Centre, Turku University Hospital, Kiinamyllynkatu 4-8, 20520, Turku, Finland.,Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - J Raiko
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - M U-Din
- Turku PET Centre, Turku University Hospital, Kiinamyllynkatu 4-8, 20520, Turku, Finland.,Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - T Niemi
- Department of Surgery, Turku University Hospital, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - M Taittonen
- Department of Anesthesiology, Turku University Hospital, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - J Laine
- Department of Pathology, Turku University Hospital, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - N Savisto
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - M Haaparanta-Solin
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland.,MediCity Research Laboratories, University of Turku, Tykistökatu 6A, 20520, Turku, Finland
| | - P Nuutila
- Turku PET Centre, Turku University Hospital, Kiinamyllynkatu 4-8, 20520, Turku, Finland.,Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - K A Virtanen
- Turku PET Centre, Turku University Hospital, Kiinamyllynkatu 4-8, 20520, Turku, Finland. .,Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland. .,Institute of Public Health and Clinical Nutrition, University of Eastern Finland, PL 1627, 70211, Kuopio, Finland.
| |
Collapse
|
17
|
Ter Voert EEGW, Svirydenka H, Müller J, Becker AS, Balaz M, Efthymiou V, Maushart CI, Gashi G, Wolfrum C, Betz MJ, Burger IA. Low-dose 18F-FDG TOF-PET/MR for accurate quantification of brown adipose tissue in healthy volunteers. EJNMMI Res 2020; 10:5. [PMID: 31974702 PMCID: PMC6977803 DOI: 10.1186/s13550-020-0592-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 01/12/2020] [Indexed: 12/12/2022] Open
Abstract
Background Positron emission tomography (PET) is increasingly applied for in vivo brown adipose tissue (BAT) research in healthy volunteers. To limit the radiation exposure, the injected 18F-FDG tracer dose should be as low as possible. With simultaneous PET/MR imaging, the radiation exposure due to computed tomography (CT) can be avoided, but more importantly, the PET acquisition time can often be increased to match the more extensive magnetic resonance (MR) imaging protocol. The potential gain in detected coincidence counts, due to the longer acquisition time, can then be applied to decrease the injected tracer dose. The aim of this study was to investigate the minimal 18F-FDG dose for a 10-min time-of-flight (TOF) PET/MR acquisition that would still allow accurate quantification of supraclavicular BAT volume and activity. Methods Twenty datasets from 13 volunteers were retrospectively included from a prospective clinical study. PET emission datasets were modified to simulate step-wise reductions of the original 75 MBq injected dose. The resulting PET images were visually and quantitatively assessed and compared to a 4-min reference scan. For the visual assessment, the image quality and artifacts were scored using a 5-point and a 3-point Likert scale. For the quantitative analysis, image noise and artifacts, BAT metabolic activity, BAT metabolic volume (BMV), and total BAT glycolysis (TBG) were investigated. Results The visual assessment showed still good image quality for the 35%, 30%, and 25% activity reconstructions with no artifacts. Quantitatively, the background noise was similar to the reference for the 35% and 30% activity reconstructions and the artifacts started to increase significantly in the 25% and lower activity reconstructions. There was no significant difference in supraclavicular BAT metabolic activity, BMV, and TBG between the reference and the 35% to 20% activity reconstructions. Conclusions This study indicates that when the PET acquisition time is matched to the 10-min MRI protocol, the injected 18F-FDG tracer dose can be reduced to approximately 19 MBq (25%) while maintaining image quality and accurate supraclavicular BAT quantification. This could decrease the effective dose from 1.4 mSv to 0.36 mSv.
Collapse
Affiliation(s)
- Edwin E G W Ter Voert
- Department of Nuclear Medicine, University Hospital Zürich, Rämistrasse 100, 8091, Zürich, Switzerland. .,University of Zurich, Rämistrasse 71, 8006, Zürich, Switzerland.
| | - Hanna Svirydenka
- Department of Nuclear Medicine, University Hospital Zürich, Rämistrasse 100, 8091, Zürich, Switzerland.,Department of Nuclear Medicine, Medical University Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Julian Müller
- Department of Nuclear Medicine, University Hospital Zürich, Rämistrasse 100, 8091, Zürich, Switzerland
| | - Anton S Becker
- Department of Health Sciences and Technology, Institute of Food, Nutrition and Health, ETH Zürich, Schorenstrasse 16, 8603, Schwerzenbach, Switzerland.,Institute of Diagnostic and Interventional Radiology, University Hospital Zürich, Rämistrasse 100, 8091, Zürich, Switzerland
| | - Miroslav Balaz
- Department of Health Sciences and Technology, Institute of Food, Nutrition and Health, ETH Zürich, Schorenstrasse 16, 8603, Schwerzenbach, Switzerland
| | - Vissarion Efthymiou
- Department of Health Sciences and Technology, Institute of Food, Nutrition and Health, ETH Zürich, Schorenstrasse 16, 8603, Schwerzenbach, Switzerland
| | - Claudia Irene Maushart
- Department of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland.,University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Gani Gashi
- Department of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland.,University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Christian Wolfrum
- Department of Health Sciences and Technology, Institute of Food, Nutrition and Health, ETH Zürich, Schorenstrasse 16, 8603, Schwerzenbach, Switzerland
| | - Matthias J Betz
- Department of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland.,University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Irene A Burger
- Department of Nuclear Medicine, University Hospital Zürich, Rämistrasse 100, 8091, Zürich, Switzerland.,Department of Nuclear Medicine, Kantonsspital Baden, Im Ergel 1, 5404, Baden, Switzerland
| |
Collapse
|
18
|
Wu M, Junker D, Branca RT, Karampinos DC. Magnetic Resonance Imaging Techniques for Brown Adipose Tissue Detection. Front Endocrinol (Lausanne) 2020; 11:421. [PMID: 32849257 PMCID: PMC7426399 DOI: 10.3389/fendo.2020.00421] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 05/27/2020] [Indexed: 12/11/2022] Open
Abstract
Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) methods can non-invasively assess brown adipose tissue (BAT) structure and function. Recently, MRI and MRS have been proposed as a means to differentiate BAT from white adipose tissue (WAT) and to extract morphological and functional information on BAT inaccessible by other means. Specifically, proton MR (1H) techniques, such as proton density fat fraction mapping, diffusion imaging, and intermolecular multiple quantum coherence imaging, have been employed to access BAT microstructure; MR thermometry, relaxometry, and MRI and MRS with 31P, 2H, 13C, and 129Xe have shown to provide complementary information on BAT function. The purpose of the present review is to provide a comprehensive overview of MR imaging and spectroscopy techniques used to detect BAT in rodents and in humans. The present work discusses common challenges of current methods and provides an outlook on possible future directions of using MRI and MRS in BAT studies.
Collapse
Affiliation(s)
- Mingming Wu
- Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
- *Correspondence: Mingming Wu
| | - Daniela Junker
- Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Rosa Tamara Branca
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Dimitrios C. Karampinos
- Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
| |
Collapse
|
19
|
Pan R, Zhu X, Maretich P, Chen Y. Metabolic Improvement via Enhancing Thermogenic Fat-Mediated Non-shivering Thermogenesis: From Rodents to Humans. Front Endocrinol (Lausanne) 2020; 11:633. [PMID: 33013706 PMCID: PMC7511774 DOI: 10.3389/fendo.2020.00633] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/05/2020] [Indexed: 12/28/2022] Open
Abstract
Brown and beige adipose tissues play a large role in non-shivering thermogenesis (NST) in mammals, and subsequently have been studied for decades as potential therapeutic targets to treat obesity and its related metabolic diseases. However, the mechanistic regulation of brown/beige adipose tissue induction and maintenance in humans is very limited due to the ethical reasons. In fact, metabolic signaling has primarily been investigated using rodent models. A better understanding of non-shivering thermogenesis in humans is thus vital and urgent in order to treat obesity by targeting human brown adipose tissue (BAT). In this review, we summarize the anatomical and physiological differences between rodent and human BAT, current useful and mostly non-invasive methods in studying human BAT, as well as recent advancements targeting thermogenic adipocytes as a means to combat metabolic diseases in humans. Furthermore, we also discuss several novel relevant strategies of therapeutic interventions, which has been attempted in rodent experiments, and possible future investigations in humans in this field.
Collapse
Affiliation(s)
- Ruping Pan
- Department of Nuclear Medicine, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaohua Zhu
- Department of Nuclear Medicine, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Pema Maretich
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Yong Chen
- Department of Endocrinology, Internal Medicine, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
- *Correspondence: Yong Chen
| |
Collapse
|
20
|
McNeill BT, Morton NM, Stimson RH. Substrate Utilization by Brown Adipose Tissue: What's Hot and What's Not? Front Endocrinol (Lausanne) 2020; 11:571659. [PMID: 33101206 PMCID: PMC7545119 DOI: 10.3389/fendo.2020.571659] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 09/14/2020] [Indexed: 12/20/2022] Open
Abstract
Our understanding of brown adipose tissue (BAT) function in humans has increased rapidly over the past 10 years. This is predominantly due to the development of powerful non-invasive imaging techniques such as positron emission tomography that can quantify BAT mass and function using metabolic tracers. Activation of BAT during cold-induced thermogenesis is an effective way to dissipate energy to generate heat and requires utilization of multiple energy substrates for optimal function. This has led to interest in the activation of BAT as a potential therapeutic target for type 2 diabetes, dyslipidaemia, and obesity. Here, we provide an overview of the current understanding of BAT substrate utilization in humans and highlight additional mechanisms found in rodents, where BAT more prominently contributes to energy expenditure. During thermogenesis, BAT demonstrates substantially increased glucose uptake which appears to be critical for BAT function. However, glucose is not fully oxidized, with a large proportion converted to lactate. The primary energy substrate for thermogenesis is fatty acids, released from brown adipocyte triglyceride stores. Active BAT also sequesters circulating lipids to sustain optimal thermogenesis. Recent evidence reveals that metabolic intermediates from the tricarboxylic acid cycle and glycolytic pathways also play a critical role in BAT function. Understanding the role of these metabolites in regulating thermogenesis and whole body substrate utilization may elucidate novel strategies for therapeutic BAT activation.
Collapse
|