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Blondin DP, Haman F, Swibas TM, Hogan-Lamarre S, Dumont L, Guertin J, Richard G, Weissenburger Q, Hildreth KL, Schauer I, Panter S, Wyland L, Carpentier AC, Miao Y, Shi J, Juarez-Colunga E, Kohrt WM, Melanson EL. Brown adipose tissue metabolism in women is dependent on ovarian status. Am J Physiol Endocrinol Metab 2024; 326:E588-E601. [PMID: 38477875 PMCID: PMC11211003 DOI: 10.1152/ajpendo.00077.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 03/12/2024] [Accepted: 03/12/2024] [Indexed: 03/14/2024]
Abstract
In rodents, loss of estradiol (E2) reduces brown adipose tissue (BAT) metabolic activity. Whether E2 impacts BAT activity in women is not known. BAT oxidative metabolism was measured in premenopausal (n = 27; 35 ± 9 yr; body mass index = 26.0 ± 5.3 kg/m2) and postmenopausal (n = 25; 51 ± 8 yr; body mass index = 28.0 ± 5.0 kg/m2) women at room temperature and during acute cold exposure using [11C]acetate with positron emission tomography coupled with computed tomograph. BAT glucose uptake was also measured during acute cold exposure using 2-deoxy-2-[18F]fluoro-d-glucose. To isolate the effects of ovarian hormones from biological aging, measurements were repeated in a subset of premenopausal women (n = 8; 40 ± 4 yr; BMI = 28.0 ± 7.2 kg/m2) after 6 mo of gonadotropin-releasing hormone agonist therapy to suppress ovarian hormones. At room temperature, there was no difference in BAT oxidative metabolism between premenopausal (0.56 ± 0.31 min-1) and postmenopausal women (0.63 ± 0.28 min-1). During cold exposure, BAT oxidative metabolism (1.28 ± 0.85 vs. 0.91 ± 0.63 min-1, P = 0.03) and net BAT glucose uptake (84.4 ± 82.5 vs. 29.7 ± 31.4 nmol·g-1·min-1, P < 0.01) were higher in premenopausal than postmenopausal women. In premenopausal women who underwent gonadotropin-releasing hormone agonist, cold-stimulated BAT oxidative metabolism was reduced to a similar level (from 1.36 ± 0.66 min-1 to 0.91 ± 0.41 min-1) to that observed in postmenopausal women (0.91 ± 0.63 min-1). These results provide the first evidence in humans that reproductive hormones are associated with BAT oxidative metabolism and suggest that BAT may be a target to attenuate age-related reduction in energy expenditure and maintain metabolic health in postmenopausal women.NEW & NOTEWORTHY In rodents, loss of estrogen reduces brown adipose tissue (BAT) activity. Whether this is true in humans is not known. We found that BAT oxidative metabolism and glucose uptake were lower in postmenopausal compared to premenopausal women. In premenopausal women who underwent ovarian suppression to reduce circulating estrogen, BAT oxidative metabolism was reduced to postmenopausal levels. Thus the loss of ovarian function in women leads to a reduction in BAT metabolic activity independent of age.
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Affiliation(s)
- Denis P Blondin
- Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
- Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
| | - François Haman
- School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Tracy M Swibas
- Division of Geriatric Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Sophie Hogan-Lamarre
- Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Lauralyne Dumont
- Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Jolan Guertin
- Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Gabriel Richard
- Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Quentin Weissenburger
- Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Kerry L Hildreth
- Division of Geriatric Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Irene Schauer
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Eastern Colorado Veterans Affairs Geriatric Research, Education, and Clinical Center, Denver, Colorado, United States
| | - Shelby Panter
- Anschutz Health and Wellness Center, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Liza Wyland
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - André C Carpentier
- Division of Endocrinology, Department of Medicine, Faculty of Medicine and Health Sciences, Centre de Recherche du Centre Hospitalier, Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Yubin Miao
- Department of Radiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Jiayuan Shi
- Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Elizabeth Juarez-Colunga
- Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Eastern Colorado Veterans Affairs Geriatric Research, Education, and Clinical Center, Denver, Colorado, United States
| | - Wendy M Kohrt
- Division of Geriatric Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Eastern Colorado Veterans Affairs Geriatric Research, Education, and Clinical Center, Denver, Colorado, United States
| | - Edward L Melanson
- Division of Geriatric Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Eastern Colorado Veterans Affairs Geriatric Research, Education, and Clinical Center, Denver, Colorado, United States
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King KE, McCormick JJ, McManus MK, Janetos KMT, Goulet N, Kenny GP. Impaired autophagy following ex vivo cooling of simulated hypothermic temperatures in peripheral blood mononuclear cells from young and older adults. J Therm Biol 2024; 121:103831. [PMID: 38565070 DOI: 10.1016/j.jtherbio.2024.103831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/20/2023] [Accepted: 03/13/2024] [Indexed: 04/04/2024]
Abstract
Hypothermia is a critical consequence of extreme cold exposure that increases the risk of cold-related injury and death in humans. While the initiation of cytoprotective mechanisms including the process of autophagy and the heat shock response (HSR) is crucial to cellular survival during periods of stress, age-related decrements in these systems may underlie cold-induced cellular vulnerability in older adults. Moreover, whether potential sex-related differences in autophagic regulation influence the human cold stress response remain unknown. We evaluated the effect of age and sex on mechanisms of cytoprotection (autophagy and the HSR) and cellular stress (apoptotic signaling and the acute inflammatory response) during ex vivo hypothermic cooling. Venous blood samples from 20 healthy young (10 females; mean [SD]: 22 [2] years) and 20 healthy older (10 females; 66 [5] years) adults were either isolated immediately (baseline) for peripheral blood mononuclear cells (PBMCs) or exposed to water bath temperatures maintained at 37, 35, 33, 31, or 4 °C for 90 min before PBMC isolation. Proteins associated with autophagy, apoptosis, the HSR, and inflammation were analyzed via Western blotting. Indicators of autophagic initiation and signaling (LC3, ULK1, and beclin-2) and the HSR (HSP90 and HSP70) increased when exposed to hypothermic temperatures in young and older adults (all p ≤ 0.007). Sex-related differences were only observed with autophagic initiation (ULK1; p = 0.015). However, despite increases in autophagic initiators ULK1 and beclin-2 (all p < 0.001), this was paralleled by autophagic dysfunction (increased p62) in all groups (all p < 0.001). Further, apoptotic (cleaved-caspase-3) and inflammatory (IL-6 and TNF-α) signaling increased in all groups (all p < 0.001). We demonstrated that exposure to hypothermic conditions is associated with autophagic dysfunction, irrespective of age or sex, although there may exist innate sex-related differences in cytoprotection in response to cold exposure as evidenced through altered autophagic initiation.
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Affiliation(s)
- Kelli E King
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - James J McCormick
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Morgan K McManus
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Kristina-Marie T Janetos
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Nicholas Goulet
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada; Behavioural and Metabolic Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Glen P Kenny
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada; Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.
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3
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Fernández-Peña C, Reimúndez A, Viana F, Arce VM, Señarís R. Sex differences in thermoregulation in mammals: Implications for energy homeostasis. Front Endocrinol (Lausanne) 2023; 14:1093376. [PMID: 36967809 PMCID: PMC10030879 DOI: 10.3389/fendo.2023.1093376] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 02/06/2023] [Indexed: 03/10/2023] Open
Abstract
Thermal homeostasis is a fundamental process in mammals, which allows the maintenance of a constant internal body temperature to ensure an efficient function of cells despite changes in ambient temperature. Increasing evidence has revealed the great impact of thermoregulation on energy homeostasis. Homeothermy requires a fine regulation of food intake, heat production, conservation and dissipation and energy expenditure. A great interest on this field of research has re-emerged following the discovery of thermogenic brown adipose tissue and browning of white fat in adult humans, with a potential clinical relevance on obesity and metabolic comorbidities. However, most of our knowledge comes from male animal models or men, which introduces unwanted biases on the findings. In this review, we discuss how differences in sex-dependent characteristics (anthropometry, body composition, hormonal regulation, and other sexual factors) influence numerous aspects of thermal regulation, which impact on energy homeostasis. Individuals of both sexes should be used in the experimental paradigms, considering the ovarian cycles and sexual hormonal regulation as influential factors in these studies. Only by collecting data in both sexes on molecular, functional, and clinical aspects, we will be able to establish in a rigorous way the real impact of thermoregulation on energy homeostasis, opening new avenues in the understanding and treatment of obesity and metabolic associated diseases.
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Affiliation(s)
| | - Alfonso Reimúndez
- Department of Physiology, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Félix Viana
- Institute of Neuroscience, University Miguel Hernández (UMH)-CSIC, Alicante, Spain
| | - Victor M. Arce
- Department of Physiology, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain
- *Correspondence: Rosa Señarís, ; Victor M. Arce,
| | - Rosa Señarís
- Department of Physiology, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain
- *Correspondence: Rosa Señarís, ; Victor M. Arce,
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Haman F, Souza SCS, Castellani JW, Dupuis MP, Friedl KE, Sullivan-Kwantes W, Kingma BRM. Human vulnerability and variability in the cold: Establishing individual risks for cold weather injuries. Temperature (Austin) 2022; 9:158-195. [PMID: 36106152 PMCID: PMC9467591 DOI: 10.1080/23328940.2022.2044740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/11/2022] [Accepted: 02/16/2022] [Indexed: 01/08/2023] Open
Abstract
Human tolerance to cold environments is extremely limited and responses between individuals is highly variable. Such physiological and morphological predispositions place them at high risk of developing cold weather injuries [CWI; including hypothermia and/or non-freezing (NFCI) and freezing cold injuries (FCI)]. The present manuscript highlights current knowledge on the vulnerability and variability of human cold responses and associated risks of developing CWI. This review 1) defines and categorizes cold stress and CWI, 2) presents cold defense mechanisms including biological adaptations, acute responses and acclimatization/acclimation and, 3) proposes mitigation strategies for CWI. This body of evidence clearly indicates that all humans are at risk of developing CWI without adequate knowledge and protective equipment. In addition, we show that while body mass plays a key role in mitigating risks of hypothermia between individuals and populations, NFCI and FCI depend mainly on changes in peripheral blood flow and associated decrease in skin temperature. Clearly, understanding the large interindividual variability in morphology, insulation, and metabolism is essential to reduce potential risks for CWI between and within populations.
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Affiliation(s)
- François Haman
- Faculty of Health Sciences, University of Ottawa, Ottawa,Ontario, Canada
| | - Sara C. S. Souza
- Faculty of Health Sciences, University of Ottawa, Ottawa,Ontario, Canada
| | - John W. Castellani
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
| | - Maria-P. Dupuis
- Faculty of Health Sciences, University of Ottawa, Ottawa,Ontario, Canada
| | - Karl E. Friedl
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
| | - Wendy Sullivan-Kwantes
- Biophysics and Biomedical Modeling Division, Defence Research Development Canada-Toronto, Defence Research and Development Canada, Ontario, Canada
| | - Boris R. M. Kingma
- Netherlands Organization for Applied Scientific Research, Department of Human Performance, Unit Defence, Safety and Security, Soesterberg, The Netherlands
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Dumont L, Lessard R, Semeniuk K, Chahrour H, McCormick JJ, Acosta FM, Blondin DP, Haman F. Thermogenic responses to different clamped skin temperatures in cold-exposed men and women. Am J Physiol Regul Integr Comp Physiol 2022; 323:R149-R160. [PMID: 35411809 DOI: 10.1152/ajpregu.00268.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Despite many decades of research examining thermoregulatory responses under varying cold stresses in humans, very little is known about the variability in metabolic heat production and shivering activity. Here, we used a novel closed-loop mean skin temperature clamping technique with a liquid-conditioned suit to isolate the effects of mean skin temperature on the subjective evaluation of thermal sensation, heat production, shivering responses, and oxidative fuel selection in young, lean and healthy men (n = 12) and women (n = 12). Our results showed a skin temperature-dependent increase in metabolic heat production (5.2±1.0 kJ/min, 5.9±1.0 kJ/min and 7.0±1.0 kJ/min with skin temperature maintained at 31°C, 29°C and 27°C, respectively; P< 0.0001) and shivering intensity in both men and women (0.6±0.1 %MVC, 1.1±0.4 %MVC and 2.5±0.7 %MVC, respectively; P<0.0001), including sex-dependent differences in heat production at all three temperatures (P < 0.005). Even when controlling for lean body mass and fat mass, sex differences persisted (P = 0.048 and P = 0.004, respectively), whereas controlling for differences in body surface area eliminated these differences. Interestingly, there were no sex differences in the cold-induced change in thermogenesis. Despite clamping skin temperature, there was tremendous variability in the rate of heat production and shivering intensity. Collectively this data suggests that many of the inter-individual differences in thermogenesis and shivering may be explained by differences in morphology and body composition.
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Affiliation(s)
- Lauralyne Dumont
- Faculty of Medicine and Health Sciences, Department of Pharmacology-Physiology and Centre de recherche du Centre hospitalier universitaire de Sherbrooke (CRCHUS), Sherbrooke, Quebec, Canada
| | - Raphael Lessard
- Faculty of Health Sciences, University of Ottawa, Ottawa, Canada
| | - Kevin Semeniuk
- Faculty of Health Sciences, University of Ottawa, Ottawa, Canada
| | | | | | - Francisco M Acosta
- PROFITH "PROmoting FITness and Health through physical activity" Research Group, Department of Physical and Sports Education, Sport and Health University Research Institute, Faculty of Sports Science, University of Granada, Granada, Spain.,Turku PET Centre, University of Turku, Turku University Hospital, Turku, Finland
| | - Denis P Blondin
- Faculty of Medicine and Health Sciences, Department of Medicine, Division of Neurology, Université de Sherbrooke and Centre de recherche du Centre hospitalier universitaire de Sherbrooke (CRCHUS), Sherbrooke, Quebec, Canada
| | - Francois Haman
- Faculty of Health Sciences, University of Ottawa, Ottawa, Canada
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Greenfield AM, Charkoudian N, Alba BK. Influences of ovarian hormones on physiological responses to cold in women. Temperature (Austin) 2021; 9:23-45. [DOI: 10.1080/23328940.2021.1953688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Andrew Martin Greenfield
- Thermal & Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA
- Oak Ridge Institute of Science and Education, Belcamp, MD, USA
| | - Nisha Charkoudian
- Thermal & Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Billie Katherine Alba
- Thermal & Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA
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Ivanova YM, Blondin DP. Examining the benefits of cold exposure as a therapeutic strategy for obesity and type 2 diabetes. J Appl Physiol (1985) 2021; 130:1448-1459. [PMID: 33764169 DOI: 10.1152/japplphysiol.00934.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The pathogenesis of metabolic diseases such as obesity and type 2 diabetes are characterized by a progressive dysregulation in energy partitioning, often leading to end-organ complications. One emerging approach proposed to target this metabolic dysregulation is the application of mild cold exposure. In healthy individuals, cold exposure can increase energy expenditure and whole body glucose and fatty acid utilization. Repeated exposures can lower fasting glucose and insulin levels and improve dietary fatty acid handling, even in healthy individuals. Despite its apparent therapeutic potential, little is known regarding the effects of cold exposure in populations for which this stimulation could benefit the most. The few studies available have shown that both acute and repeated exposures to the cold can improve insulin sensitivity and reduce fasting glycemia in individuals with type 2 diabetes. However, critical gaps remain in understanding the prolonged effects of repeated cold exposures on glucose regulation and whole body insulin sensitivity in individuals with metabolic syndrome. Much of the metabolic benefits appear to be attributable to the recruitment of shivering skeletal muscles. However, further work is required to determine whether the broader recruitment of skeletal muscles observed during cold exposure can confer metabolic benefits that surpass what has been historically observed from endurance exercise. In addition, although cold exposure offers unique cardiovascular responses for a physiological stimulus that increases energy expenditure, further work is required to determine how acute and repeated cold exposure can impact cardiovascular responses and myocardial function across a broader scope of individuals.
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Affiliation(s)
- Yoanna M Ivanova
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada.,Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Denis P Blondin
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada.,Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
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8
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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.
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9
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Kaikaew K, van den Beukel JC, Neggers SJCMM, Themmen APN, Visser JA, Grefhorst A. Sex difference in cold perception and shivering onset upon gradual cold exposure. J Therm Biol 2018; 77:137-144. [PMID: 30196892 DOI: 10.1016/j.jtherbio.2018.08.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 08/21/2018] [Accepted: 08/22/2018] [Indexed: 01/22/2023]
Abstract
To maintain a thermal balance when experiencing cold, humans reduce heat loss and enhance heat production. A potent and rapid mechanism for heat generation is shivering. Research has shown that women prefer a warmer environment and feel less comfortable than men in the same thermal condition. Using the Blanketrol® III, a temperature management device commonly used to study brown adipose tissue activity, we tested whether the experimental temperature (TE) at which men and women start to shiver differs. Twenty male and 23 female volunteers underwent a cooling protocol, starting at 24 °C and gradually decreasing by 1-2 °C every 5 min until an electromyogram detected the shivering or the temperature reached 9 °C. Women started shivering at a higher TE than men (11.3 ± 1.8 °C for women vs 9.6 ± 1.8 °C for men, P = 0.003). In addition, women felt cool, scored by a visual analogue scale, at a higher TE than men (18.3 ± 3.0 °C for women vs 14.6 ± 2.6 °C for men, P < 0.001). This study demonstrates a sex difference in response to cold exposure: women require shivering as a source of heat production earlier than men. This difference could be important and sex should be considered when using cooling protocols in physiological studies.
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Affiliation(s)
- Kasiphak Kaikaew
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, the Netherlands; Department of Physiology, Faculty of Medicine, Chulalongkorn University, 1873, Rama IV Road, Pathumwan, Bangkok 10330, Thailand
| | - Johanna C van den Beukel
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, the Netherlands
| | - Sebastian J C M M Neggers
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, the Netherlands
| | - Axel P N Themmen
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, the Netherlands
| | - Jenny A Visser
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, the Netherlands.
| | - Aldo Grefhorst
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, the Netherlands
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Blondin DP, Haman F. Shivering and nonshivering thermogenesis in skeletal muscles. HANDBOOK OF CLINICAL NEUROLOGY 2018; 156:153-173. [PMID: 30454588 DOI: 10.1016/b978-0-444-63912-7.00010-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Humans have inherited complex neural circuits which drive behavioral, somatic, and autonomic thermoregulatory responses to defend their body temperature. While they are well adapted to dissipate heat in warm climates, they have a reduced capacity to preserve it in cold environments. Consequently, heat production is critical to defending their core temperature. As in other large mammals, skeletal muscles are the primary source of heat production recruited in cold-exposed humans. This is achieved voluntarily in the form of contractions from exercising muscles or involuntarily in the form of contractions from shivering muscles and the recruitment of nonshivering mechanisms. This review describes our current understanding of shivering and nonshivering thermogenesis in skeletal muscles, from the neural circuitry driving their recruitment to the metabolic substrates that fuel them. The presence of these heat-producing mechanisms can be measured in vivo by combining indirect respiratory calorimetry with electromyography or biomedical imaging modalities. Indeed, much of what is known regarding shivering in humans and other animal models stems from studies performed using these methods combined with in situ and in vivo neurologic techniques. More recent investigations have focused on understanding the metabolic processes that produce the heat from both contracting and noncontracting mechanisms. With the growing interest in the potential therapeutic benefits of shivering and nonshivering skeletal muscle to counter the effects of neuromuscular, cardiovascular, and metabolic diseases, we expect this field to continue its growth in the coming years.
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Affiliation(s)
- Denis P Blondin
- Department of Medicine, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada.
| | - François Haman
- Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada
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11
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Haman F, Blondin DP. Shivering thermogenesis in humans: Origin, contribution and metabolic requirement. Temperature (Austin) 2017; 4:217-226. [PMID: 28944268 DOI: 10.1080/23328940.2017.1328999] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/07/2017] [Accepted: 05/08/2017] [Indexed: 01/01/2023] Open
Abstract
As endotherms, humans exposed to a compensable cold environment rely on an increase in thermogenic rate to counteract heat lost to the environment, thereby maintaining a stable core temperature. This review focuses primarily on the most important contributor of heat production in cold-exposed adult humans, shivering skeletal muscles. Specifically, it presents current understanding on (1) the origins of shivering, (2) the contribution of shivering to total heat production and (3) the metabolic requirements of shivering. Although shivering had commonly been measured as a metabolic outcome measure, considerable research is still needed to clearly identify the neuroanatomical structures and circuits that initiate and modulate shivering and drives the shivering patterns (continuous and burst shivering). One thing is clear, the thermogenic rate in humans can be maintained despite significant inter-individual differences in the thermogenic contribution of shivering, the muscles recruited in shivering, the burst shivering rate and the metabolic substrates used to support shivering. It has also become evident that the variability in burst shivering rate between individuals, despite not influencing heat production, does play a key role in orchestrating metabolic fuel selection in the cold. In addition, advances in our understanding of the thermogenic role of brown adipose tissue have been able to explain, at least in part, the large inter-individual differences in the contribution of shivering to total heat production. Whether these differences in the thermogenic role of shivering have any bearing on cold endurance and survival remains to be established. Despite the available research describing the relative thermogenic importance of shivering skeletal muscles in humans, the advancement in our understanding of how shivering is initiated and modulated is needed. Such research is critical to consider strategies to either reduce its role to improve occupational performance or exploit its metabolic potential for clinical purposes.
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Affiliation(s)
- François Haman
- Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada
| | - Denis P Blondin
- Department of Medicine, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada
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Blondin DP, Daoud A, Taylor T, Tingelstad HC, Bézaire V, Richard D, Carpentier AC, Taylor AW, Harper ME, Aguer C, Haman F. Four-week cold acclimation in adult humans shifts uncoupling thermogenesis from skeletal muscles to brown adipose tissue. J Physiol 2017; 595:2099-2113. [PMID: 28025824 DOI: 10.1113/jp273395] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 11/21/2016] [Indexed: 12/27/2022] Open
Abstract
KEY POINTS Muscle-derived thermogenesis during acute cold exposure in humans consists of a combination of cold-induced increases in skeletal muscle proton leak and shivering. Daily cold exposure results in an increase in brown adipose tissue oxidative capacity coupled with a decrease in the cold-induced skeletal muscle proton leak and shivering intensity. Improved coupling between electromyography-determined muscle activity and whole-body heat production following cold acclimation suggests a maintenance of ATPase-dependent thermogenesis and decrease in skeletal muscle ATPase independent thermogenesis. Although daily cold exposure did not change the fibre composition of the vastus lateralis, the fibre composition was a strong predictor of the shivering pattern evoked during acute cold exposure. ABSTRACT We previously showed that 4 weeks of daily cold exposure in humans can increase brown adipose tissue (BAT) volume by 45% and oxidative metabolism by 182%. Surprisingly, we did not find a reciprocal reduction in shivering intensity when exposed to a mild cold (18°C). The present study aimed to determine whether changes in skeletal muscle oxidative metabolism or shivering activity could account for these unexpected findings. Nine men participated in a 4 week cold acclimation intervention (10°C water circulating in liquid-conditioned suit, 2 h day-1 , 5 days week-1 ). Shivering intensity and pattern were measured continuously during controlled cold exposure (150 min at 4 °C) before and after the acclimation. Muscle biopsies from the m. vastus lateralis were obtained to measure oxygen consumption rate and proton leak of permeabilized muscle fibres. Cold acclimation elicited a modest 21% (P < 0.05) decrease in whole-body and m. vastus lateralis shivering intensity. Furthermore, cold acclimation abolished the acute cold-induced increase in proton leak. Although daily cold exposure did not change the fibre composition of the m. vastus lateralis, fibre composition was a strong predictor of the shivering pattern evoked during acute cold. We conclude that muscle-derived thermogenesis during acute cold exposure in humans is not only limited to shivering, but also includes cold-induced increases in proton leak. The efficiency of muscle oxidative phosphorylation improves with cold acclimation, suggesting that reduced muscle thermogenesis occurs through decreased proton leak, in addition to decreased shivering intensity as BAT capacity and activity increase. These changes occur with no net difference in whole-body thermogenesis.
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Affiliation(s)
- Denis P Blondin
- Department of Medicine, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada
| | - Amani Daoud
- Faculty of Science, University of Ottawa, Ottawa, Canada.,Institut de recherche de l'Hôpital Montfort, Ottawa, Canada
| | - Taryn Taylor
- Carleton Sports Medicine Clinic, Carleton University, Ottawa, Canada
| | | | - Véronic Bézaire
- Department of Chemistry, Carleton University, Ottawa, Canada
| | - Denis Richard
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Canada
| | - André C Carpentier
- Department of Medicine, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada
| | - Albert W Taylor
- Faculty of Health Sciences, University of Western Ontario, London, Canada
| | - Mary-Ellen Harper
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Céline Aguer
- Institut de recherche de l'Hôpital Montfort, Ottawa, Canada.,Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - François Haman
- Faculty of Health Sciences, University of Ottawa, Ottawa, Canada
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Blondin DP, Tingelstad HC, Mantha OL, Gosselin C, Haman F. Maintaining thermogenesis in cold exposed humans: relying on multiple metabolic pathways. Compr Physiol 2015; 4:1383-402. [PMID: 25428848 DOI: 10.1002/cphy.c130043] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In cold exposed humans, increasing thermogenic rate is essential to prevent decreases in core temperature. This review describes the metabolic requirements of thermogenic pathways, mainly shivering thermogenesis, the largest contributor of heat. Research has shown that thermogenesis is sustained from a combination of carbohydrates, lipids, and proteins. The mixture of fuels is influenced by shivering intensity and pattern as well as by modifications in energy reserves and nutritional status. To date, there are no indications that differences in the types of fuel being used can alter shivering and overall heat production. We also bring forth the potential contribution of nonshivering thermogenesis in adult humans via the activation of brown adipose tissue (BAT) and explore some means to stimulate the activity of this highly thermogenic tissue. Clearly, the potential role of BAT, especially in young lean adults, can no longer be ignored. However, much work remains to clearly identify the quantitative nature of this tissue's contribution to total thermogenic rate and influence on shivering thermogenesis. Identifying ways to potentiate the effects of BAT via cold acclimation and/or the ingestion of compounds that stimulate the thermogenic process may have important implications in cold endurance and survival.
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Affiliation(s)
- Denis P Blondin
- Department of Medicine, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada
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Wang HS, Han JS. Research progress on combat trauma treatment in cold regions. Mil Med Res 2014; 1:8. [PMID: 25722866 PMCID: PMC4340833 DOI: 10.1186/2054-9369-1-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 04/17/2014] [Indexed: 12/29/2022] Open
Abstract
Cold regions are a special combat environment in which low temperatures have a great impact on human metabolism and other vital functions, including the nervous, motion, cardiovascular, circulatory, respiratory, and urinary systems; consequently, low temperatures often aggravate existing trauma, leading to high mortality rates if rapid and appropriate treatment is not provided. Hypothermia is an independent risk factor of fatality following combat trauma; therefore, proactive preventative measures are needed to reduce the rate of mortality. After summarizing the basic research on battlefield environments and progress in the prevention and treatment of trauma, this article concludes that current treatment and prevention measures for combat trauma in cold regions are inadequate. Future molecular biology studies are needed to elucidate the mechanisms and relevant cell factors underlying bodily injury caused by cold environment, a research goal will also allow further exploration of corresponding treatments.
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Affiliation(s)
- Hui-Shan Wang
- Department of Cardiovascular Surgery, General Hospital of Shenyang Military Command, Shenyang, 110016 China
| | - Jin-Song Han
- Department of Cardiovascular Surgery, General Hospital of Shenyang Military Command, Shenyang, 110016 China
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Effects of green tea extracts on non-shivering thermogenesis during mild cold exposure in young men. Br J Nutr 2012; 110:282-8. [PMID: 23237788 DOI: 10.1017/s0007114512005089] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The effects of epigallocatechin-3-gallate (EGCG) and caffeine on non-shivering thermogenesis (NST) during cold exposure is unknown. The purpose of the present study was to quantify the effects of co-ingesting EGCG and caffeine on the thermogenic responses of a 3 h cold exposure. A total of eight healthy males were exposed to mild cold, using a liquid-conditioned suit perfused with 158C water, on two occasions and consumed a placebo or an extract of 1600 mg of EGCG and 600 mg of caffeine (Green tea). Thermic, metabolic and electromyographic measurements were monitored at baseline and during the cold exposure. Results showed that the AUC of shivering intensity over the cold exposure period was reduced by approximately 20% in the Green tea (266 (SEM 6)% maximal voluntary contraction (MVC) x min) compared with the Placebo (332 (SEM 69)%MVC x min) (P=0·01) treatments. In contrast, the total AUC for energy expenditure (EE) was approximately 10% higher in the Green tea (23·5 (SEM 1·4) kJ/kg x 180 min) compared with the Placebo (327 (SEM 74) kJ/kg 180 min) (P=0·007) treatments. The decrease in shivering activity combined with an increase in EE, following the ingestion of EGCG and caffeine during the cold exposure, indicates that NST pathways can be significantly stimulated in adult human subjects. The present study provides an experimental approach for human investigations into the potential role of diet and bioactive food ingredients in modulating NST during cold exposure. Stimulating NST pathways in such a manner may also provide important targets in the search of targets for the management of obesity and diabetes.
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