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Kwok TC, Ramage LE, Kelman A, Suchacki KJ, Gray C, Boyle LD, Semple SI, MacGillivray T, MacNaught G, Patel D, van Beek EJR, Semple RK, Wakelin SJ, Stimson RH. UCP1 expression in human brown adipose tissue is inversely associated with cardiometabolic risk factors. Eur J Endocrinol 2024; 191:106-115. [PMID: 38917410 PMCID: PMC11265601 DOI: 10.1093/ejendo/lvae074] [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: 09/10/2023] [Revised: 02/02/2024] [Accepted: 06/19/2024] [Indexed: 06/27/2024]
Abstract
OBJECTIVE Brown adipose tissue (BAT) is a therapeutic target for obesity. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) is commonly used to quantify human BAT mass and activity. Detectable 18F-FDG uptake by BAT is associated with reduced prevalence of cardiometabolic disease. However, 18F-FDG uptake may not always be a reliable marker of BAT thermogenesis, for example, insulin resistance may reduce glucose uptake. Uncoupling protein 1 (UCP1) is the key thermogenic protein in BAT. Therefore, we hypothesised that UCP1 expression may be altered in individuals with cardiometabolic risk factors. METHODS We quantified UCP1 expression as an alternative marker of thermogenic capacity in BAT and white adipose tissue (WAT) samples (n = 53) and in differentiated brown and white pre-adipocytes (n = 85). RESULTS UCP1 expression in BAT, but not in WAT or brown/white differentiated pre-adipocytes, was reduced with increasing age, obesity, and adverse cardiometabolic risk factors such as fasting glucose, insulin, and blood pressure. However, UCP1 expression in BAT was preserved in obese subjects of <40 years of age. To determine if BAT activity was also preserved in vivo, we undertook a case-control study, performing 18F-FDG scanning during mild cold exposure in young (mean age ∼22 years) normal weight and obese volunteers. 18F-FDG uptake by BAT and BAT volume were similar between groups, despite increased insulin resistance. CONCLUSION 18F-FDG uptake by BAT and UCP1 expression are preserved in young obese adults. Older subjects retain precursor cells with the capacity to form new thermogenic adipocytes. These data highlight the therapeutic potential of BAT mass expansion and activation in obesity.
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Affiliation(s)
- T’ng Choong Kwok
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Lynne E Ramage
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Alexandra Kelman
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Karla J Suchacki
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Calum Gray
- Edinburgh Imaging Facility, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Luke D Boyle
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Scott I Semple
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
- Edinburgh Imaging Facility, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Tom MacGillivray
- Edinburgh Imaging Facility, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Gillian MacNaught
- Department of Radiology, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, Scotland, United Kingdom
| | - Dilip Patel
- Department of Radiology, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, Scotland, United Kingdom
| | - Edwin J R van Beek
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
- Edinburgh Imaging Facility, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Robert K Semple
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - Sonia J Wakelin
- Department of Surgery, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, Scotland, United Kingdom
| | - Roland H Stimson
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
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Ruswandi YAR, Lesmana R, Rosdianto AM, Gunadi JW, Goenawan H, Zulhendri F. Understanding the Roles of Selenium on Thyroid Hormone-Induced Thermogenesis in Adipose Tissue. Biol Trace Elem Res 2024; 202:2419-2441. [PMID: 37758980 DOI: 10.1007/s12011-023-03854-2] [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: 04/18/2023] [Accepted: 09/07/2023] [Indexed: 09/29/2023]
Abstract
Brown adipose tissue (BAT) and white adipose tissue (WAT) are known to regulate lipid metabolism. A lower amount of BAT compared to WAT, along with adipose tissue dysfunction, can result in obesity. Studies have shown that selenium supplementation protects against adipocyte dysfunction, decreases WAT triglycerides, and increases BAT triiodothyronine (T3). In this review, we discuss the relationship between selenium and lipid metabolism regulation through selenoprotein deiodinases and the role of deiodinases and thyroid hormones in the induction of adipose tissue thermogenesis. Upon 22 studies included in our review, we found that studies investigating the relationship between selenium and deiodinases demonstrated that selenium supplementation affects the iodothyronine deiodinase 2 (DIO2) protein and the expression of its associated gene, DIO2, proportionally. However, its effect on DIO1 is inconsistent while its effect on DIO3 activity is not detected. Studies have shown that the activity of deiodinases especially DIO2 protein and DIO2 gene expression is increased along with other browning markers upon white adipose tissue browning induction. Studies showed that thermogenesis is stimulated by the thyroid hormone T3 as its activity is correlated to the expression of other thermogenesis markers. A proposed mechanism of thermogenesis induction in selenium supplementation is by autophagy control. However, more studies are needed to establish the role of T3 and autophagy in adipose tissue thermogenesis, especially, since some studies have shown that thermogenesis can function even when T3 activity is lacking and studies related to autophagy in adipose tissue thermogenesis have contradictory results.
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Affiliation(s)
- Yasmin Anissa R Ruswandi
- Graduate School of Master Program in Anti-Aging and Aesthetic Medicine, Faculty of Medicine, Universitas Padjadjaran, Kabupaten Sumedang, West Java, Indonesia
| | - Ronny Lesmana
- Physiology Division, Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Jl. Raya Bandung-Sumedang, KM.21, Hegarmanah, Kec. Jatinangor, Kabupaten Sumedang, West Java, 45363, Indonesia.
| | - Aziiz Mardanarian Rosdianto
- Physiology Division, Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Jl. Raya Bandung-Sumedang, KM.21, Hegarmanah, Kec. Jatinangor, Kabupaten Sumedang, West Java, 45363, Indonesia
- Veterinary Medicine Study Program, Faculty of Medicine, Universitas Padjadjaran, Kabupaten Sumedang, West Java, Indonesia
| | - Julia Windi Gunadi
- Department of Physiology, Faculty of Medicine, Maranatha Christian University, Bandung, West Java, Indonesia
| | - Hanna Goenawan
- Physiology Division, Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Jl. Raya Bandung-Sumedang, KM.21, Hegarmanah, Kec. Jatinangor, Kabupaten Sumedang, West Java, 45363, Indonesia
| | - Felix Zulhendri
- Center of Excellence in Higher Education for Pharmaceutical Care Innovation, Universitas Padjadjaran, Kabupaten Sumedang, West Java, Indonesia
- Kebun Efi, Kabanjahe, 22171, North Sumatra, Indonesia
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3
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Carpentier AC. Tracers and Imaging of Fatty Acid and Energy Metabolism of Human Adipose Tissues. Physiology (Bethesda) 2024; 39:0. [PMID: 38113392 PMCID: PMC11283904 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.
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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
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4
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Chondronikola M, Yoshino J, Ramaswamy R, Giardina JD, Laforest R, Wahl RL, Patterson BW, Mittendorfer B, Klein S. Very-low-density lipoprotein triglyceride and free fatty acid plasma kinetics in women with high or low brown adipose tissue volume and overweight/obesity. Cell Rep Med 2024; 5:101370. [PMID: 38232692 PMCID: PMC10829791 DOI: 10.1016/j.xcrm.2023.101370] [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: 05/11/2023] [Revised: 09/18/2023] [Accepted: 12/14/2023] [Indexed: 01/19/2024]
Abstract
Although a high amount of brown adipose tissue (BAT) is associated with low plasma triglyceride concentration, the mechanism responsible for this relationship in people is not clear. Here, we evaluate the interrelationships among BAT, very-low-density lipoprotein triglyceride (VLDL-TG), and free fatty acid (FFA) plasma kinetics during thermoneutrality in women with overweight/obesity who had a low (<20 mL) or high (≥20 mL) volume of cold-activated BAT (assessed by using positron emission tomography in conjunction with 2-deoxy-2-[18F]-fluoro-glucose). We find that plasma TG and FFA concentrations are lower and VLDL-TG and FFA plasma clearance rates are faster in women with high BAT than low BAT volume, whereas VLDL-TG and FFA appearance rates in plasma are not different between the two groups. These findings demonstrate that women with high BAT volume have lower plasma TG and FFA concentrations than women with low BAT volumes because of increased VLDL-TG and FFA clearance rates. This study was registered at ClinicalTrials.gov (NCT02786251).
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Affiliation(s)
- Maria Chondronikola
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, USA; Wellcome-MRC Institute of Metabolic Science-Metabolic Research Laboratories, Medical Research Council Metabolic Diseases Unit, University of Cambridge, Cambridge, UK; Department of Nutritional Sciences and Dietetics, Harokopio University of Athens, Kallithea, Greece.
| | - Jun Yoshino
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, USA
| | - Raja Ramaswamy
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Richard Laforest
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Richard L Wahl
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Bruce W Patterson
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, USA
| | - Bettina Mittendorfer
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, USA
| | - Samuel Klein
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, USA; Sansum Diabetes Research Institute, Santa Barbara, CA, USA.
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Alabduljabbar K, Bonanos E, Miras AD, le Roux CW. Mechanisms of Action of Bariatric Surgery on Body Weight Regulation. Gastroenterol Clin North Am 2023; 52:691-705. [PMID: 37919021 DOI: 10.1016/j.gtc.2023.08.002] [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] [Indexed: 11/04/2023]
Abstract
Bariatric surgery is an effective treatment modality for obesity and obesity-associated complications. Weight loss after bariatric surgery was initially attributed to anatomic restriction or reduced energy absorption, but now it is understood that surgery treats obesity by influencing the subcortical areas of the brain to lower adipose tissue mass. There are three major phases of this process: initially the weight loss phase, followed by a phase where weight loss is maintained, and in a subset of patients a phase where weight is regained. These phases are characterized by altered appetitive behavior together with changes in energy expenditure. The mechanisms associated with the rearrangement of the gastrointestinal tract include central appetite control, release of gut peptides, change in microbiota and bile acids. However, the exact combination and timing of signals remain largely unknown.
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Affiliation(s)
- Khaled Alabduljabbar
- Diabetes Complications Research Centre, Conway Institute, University College Dublin, Dublin, Ireland; Department of Family Medicine and Polyclinics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia.
| | | | | | - Carel W le Roux
- Diabetes Complications Research Centre, Conway Institute, University College Dublin, Dublin, Ireland.
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6
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Omran F, Murphy AM, Younis AZ, Kyrou I, Vrbikova J, Hainer V, Sramkova P, Fried M, Ball G, Tripathi G, Kumar S, McTernan PG, Christian M. The impact of metabolic endotoxaemia on the browning process in human adipocytes. BMC Med 2023; 21:154. [PMID: 37076885 PMCID: PMC10116789 DOI: 10.1186/s12916-023-02857-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 04/03/2023] [Indexed: 04/21/2023] Open
Abstract
BACKGROUND Dysfunctional adipose tissue (AT) is known to contribute to the pathophysiology of metabolic disease, including type 2 diabetes mellitus (T2DM). This dysfunction may occur, in part, as a consequence of gut-derived endotoxaemia inducing changes in adipocyte mitochondrial function and reducing the proportion of BRITE (brown-in-white) adipocytes. Therefore, the present study investigated whether endotoxin (lipopolysaccharide; LPS) directly contributes to impaired human adipocyte mitochondrial function and browning in human adipocytes, and the relevant impact of obesity status pre and post bariatric surgery. METHODS Human differentiated abdominal subcutaneous (AbdSc) adipocytes from participants with obesity and normal-weight participants were treated with endotoxin to assess in vitro changes in mitochondrial function and BRITE phenotype. Ex vivo human AbdSc AT from different groups of participants (normal-weight, obesity, pre- and 6 months post-bariatric surgery) were assessed for similar analyses including circulating endotoxin levels. RESULTS Ex vivo AT analysis (lean & obese, weight loss post-bariatric surgery) identified that systemic endotoxin negatively correlated with BAT gene expression (p < 0.05). In vitro endotoxin treatment of AbdSc adipocytes (lean & obese) reduced mitochondrial dynamics (74.6% reduction; p < 0.0001), biogenesis (81.2% reduction; p < 0.0001) and the BRITE phenotype (93.8% reduction; p < 0.0001). Lean AbdSc adipocytes were more responsive to adrenergic signalling than obese AbdSc adipocytes; although endotoxin mitigated this response (92.6% reduction; p < 0.0001). CONCLUSIONS Taken together, these data suggest that systemic gut-derived endotoxaemia contributes to both individual adipocyte dysfunction and reduced browning capacity of the adipocyte cell population, exacerbating metabolic consequences. As bariatric surgery reduces endotoxin levels and is associated with improving adipocyte functionality, this may provide further evidence regarding the metabolic benefits of such surgical interventions.
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Affiliation(s)
- Farah Omran
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV2 2DX, UK
| | - Alice M Murphy
- Department of Biosciences, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK
| | - Awais Z Younis
- Department of Biosciences, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK
| | - Ioannis Kyrou
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry, CV2 2DX, UK
- Centre for Sport, Exercise and Life Sciences, Research Institute for Health & Wellbeing, Coventry University, Coventry, CV1 5FB, UK
- Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham, B4 7ET, UK
- Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
| | | | | | | | | | - Graham Ball
- Medical Technology Research Centre, Anglia Ruskin University, Cambridge, UK
| | - Gyanendra Tripathi
- Human Sciences Research Centre, College of Life and Natural Sciences, University of Derby, Derby, DE22 1GB, UK
| | - Sudhesh Kumar
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry, CV2 2DX, UK
- Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
| | - Philip G McTernan
- Department of Biosciences, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK.
| | - Mark Christian
- Department of Biosciences, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK.
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7
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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.
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Affiliation(s)
- André C Carpentier
- Division of Endocrinology, Department of Medicine, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Université de Sherbrooke, 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
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Latteri S, Sofia M, Puleo S, Di Vincenzo A, Cinti S, Castorina S. Mechanisms linking bariatric surgery to adipose tissue, glucose metabolism, fatty liver disease and gut microbiota. Langenbecks Arch Surg 2023; 408:101. [PMID: 36826628 PMCID: PMC9957865 DOI: 10.1007/s00423-023-02821-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 01/25/2023] [Indexed: 02/25/2023]
Abstract
PURPOSE In the last 20 years, bariatric surgery has achieved an important role in translational and clinical research because of obesity comorbidities. Initially, a tool to lose weight, bariatric surgery now has been shown to be involved in several metabolic pathways. METHODS We conducted a narrative review discussing the underlying mechanisms that could explain the impact of bariatric surgery and the relationship between obesity and adipose tissue, T2D, gut microbiota, and NAFLD. RESULTS Bariatric surgery has an impact in the relation between obesity and type 2 diabetes, but in addition it induces the white-to-brown adipocyte trans-differentiation, by enhancing thermogenesis. Another issue is the connection of bariatric surgery with the gut microbiota and its role in the complex mechanism underlying weight gain. CONCLUSION Bariatric surgery modifies gut microbiota, and these modifications influence lipid metabolism, leading to improvement of non-alcoholic fatty liver disease.
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Affiliation(s)
- Saverio Latteri
- Department of Medical, Surgical Sciences and Advanced Technologies "G.F. Ingrassia", University of Catania, Catania, Italy
| | - Maria Sofia
- Department of General Surgery, Cannizzaro Hospital, Via Messina 829, 95126, Catania, Italy.
| | - Stefano Puleo
- Mediterranean Foundation "GB Morgagni", Catania, Italy
| | - Angelica Di Vincenzo
- Department of Experimental and Clinical Medicine, Center of Obesity, Marche Polytechnic University, Via Tronto 10A, 60020, Ancona, Italy
| | - Saverio Cinti
- Department of Experimental and Clinical Medicine, Center of Obesity, Marche Polytechnic University, Via Tronto 10A, 60020, Ancona, Italy
| | - Sergio Castorina
- Department of Medical, Surgical Sciences and Advanced Technologies "G.F. Ingrassia", University of Catania, Catania, Italy
- Mediterranean Foundation "GB Morgagni", Catania, Italy
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9
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Chen S, Jiang Y, Qi X, Song P, Tang L, Liu H. Bioinformatics analysis to obtain critical genes regulated in subcutaneous adipose tissue after bariatric surgery. Adipocyte 2022; 11:550-561. [PMID: 36036283 PMCID: PMC9427031 DOI: 10.1080/21623945.2022.2115212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Bariatric surgery (BS) is a dependable method for managing obesity and metabolic diseases, however, the regulatory processes of lipid metabolism are still not well elucidated. Differentially expressed genes (DEGs) were analysed through three transcriptomic datasets of GSE29409, GSE59034 and GSE72158 from the GEO database regarding subcutaneous adipose tissue (SAT) after BS, and 37 DEGs were identified. The weighted gene co-expression network analysis (WGCNA), last absolute shrinkage and selection operator (LASSO) logistic regression and support vector machine-recursive feature elimination (SVM-RFE) algorithms further screened four key genes involved in the regulation of STMN2, SFRP4, APOE and MXRA5. The GSE53376 dataset was used to further confirm the differential expression of SFRP4, APOE and MXRA5 in the postoperative period. GSEA analysis reveals activation of immune-related regulatory pathways after surgery. Finally, the silencing of MXRA5 was found by experimental methods to affect the expression of PPARγ and CEBPα during the differentiation of preadipocytes, as well as to affect the formation of lipid droplets. In conclusion, SAT immunoregulation was mobilized after BS, while MXRA5 was involved in the regulation of lipid metabolism.
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Affiliation(s)
- Shuai Chen
- Center of Gastrointestinal Disease, The Affiliated Changzhou NO. 2 People’s Hospital of Nanjing Medical University, Changzhou, China
| | - Yicheng Jiang
- Center of Gastrointestinal Disease, The Affiliated Changzhou NO. 2 People’s Hospital of Nanjing Medical University, Changzhou, China
| | - Xiaoyang Qi
- Center of Gastrointestinal Disease, The Affiliated Changzhou NO. 2 People’s Hospital of Nanjing Medical University, Changzhou, China
| | - Peng Song
- Center of Gastrointestinal Disease, The Affiliated Changzhou NO. 2 People’s Hospital of Nanjing Medical University, Changzhou, China
| | - Liming Tang
- Center of Gastrointestinal Disease, The Affiliated Changzhou NO. 2 People’s Hospital of Nanjing Medical University, Changzhou, China,CONTACT Liming Tang
| | - Hanyang Liu
- Center of Gastrointestinal Disease, The Affiliated Changzhou NO. 2 People’s Hospital of Nanjing Medical University, Changzhou, China,Hanyang Liu Center of Gastrointestinal Disease, The Affiliated Changzhou NO. 2 People’s Hospital of Nanjing Medical University, 68 Gehu Rd, Wujin District, Changzhou, Jiangsu, China
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Sarma S, Palcu P. Weight loss between glucagon-like peptide-1 receptor agonists and bariatric surgery in adults with obesity: A systematic review and meta-analysis. Obesity (Silver Spring) 2022; 30:2111-2121. [PMID: 36321278 DOI: 10.1002/oby.23563] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 06/06/2022] [Accepted: 06/22/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Glucagon-like peptide-1 (GLP-1) receptor agonists recently demonstrated 15% to 20% weight loss in adults with obesity, a range which has previously been achieved only with bariatric surgery. This systematic review and meta-analysis compares weight loss between GLP-1 receptor agonists and bariatric surgery. METHODS The databases MEDLINE, MEDLINE In-Process, MEDLINE Epubs Ahead of Print, Embase Classic + Embase (OvidSP), and Cochrane (Wiley) were searched from inception to April 21, 2021, for randomized controlled trials and observational studies. Two independent reviewers extracted data, reported risk of bias, and graded certainty of evidence. Random-effects models were used to pool change in weight, BMI, and glycated hemoglobin. RESULTS Six studies, encompassing 332 patients, were included. Among randomized controlled trials, mean difference in weight between all bariatric surgery types and GLP-1 receptor agonists was -22.68 kg (95% CI: -31.41 to -13.96), mean difference in BMI was -8.18 kg/m2 (95% CI: -11.59 to -4.77), and mean difference in glycated hemoglobin was -1.28% (95% CI: -1.94% to -0.61%). Among observational studies, mean difference in weight was -25.11 kg (95% CI: -40.61 to -9.60), and mean difference in BMI was -10.60 kg/m2 (95% CI: -17.22 to -3.98). Only one observational study reported glycemic outcomes. CONCLUSION In adults with obesity, bariatric surgery still confers the highest reductions in weight and BMI but confers similar effects in glycemic control when compared with GLP-1 receptor agonists.
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Affiliation(s)
- Shohinee Sarma
- Division of Endocrinology and Metabolism, Leadership Sinai Centre for Diabetes, Sinai Health System, Toronto, Ontario, Canada
| | - Patricia Palcu
- Department of Medicine, Division of General Internal Medicine, University of Toronto, Toronto, Ontario, Canada
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11
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Guzzardi MA, Collado MC, Panetta D, Tripodi M, Iozzo P. Maternal High-Fat Diet Programs White and Brown Adipose Tissues In Vivo in Mice, with Different Metabolic and Microbiota Patterns in Obesity-Susceptible or Obesity-Resistant Offspring. Metabolites 2022; 12:metabo12090828. [PMID: 36144232 PMCID: PMC9503350 DOI: 10.3390/metabo12090828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 11/16/2022] Open
Abstract
Maternal obesity causes metabolic dysfunction in the offspring, including dysbiosis, overeating, obesity, and type 2 diabetes. Early-life phases are fundamental for developing subcutaneous (SAT) and brown adipose tissues (BAT), handling energy excesses. Imaging of 18F-fluorodeoxyglucose by positron emission tomography (PET) and radiodensity by computerized tomography (CT) allows assessing adipose tissue (AT) whitening and browning in vivo and the underlying metabolic efficiency. Our aim was to examine these in vivo traits in SAT and BAT concerning gut microbiota composition in 1- and 6-month-old mice born to normal (NDoff) and high-fat diet-fed dams (HFDoff), accounting for body weight responses. We found low radiodensity (high lipids) in HFDoff SAT at 1 month, relating to an increased abundance of Dorea genus in the caecum and activation of the fatty acid biosynthetic pathway. Instead, low BAT radiodensity and glucose uptake were seen in adult HFDoff. Glucose was shifted in favor of BAT at 1 month and SAT at 6 months. In adults, unclassified Enterococcaceae and Rikenellaceae, and Bacillus genera were negatively related to BAT, whereas unclassified Clostridiales genera were related to SAT metabolism. Stratification of HFDoff based on weight-response, namely maternal induced obesity (MIO-HFDoff) or obesity-resistant (MIOR-HFDoff), showed sex dimorphism. Both subgroups were hyperphagic, but only obese mice had hyper-leptinemia and hyper-resistinemia, together with BAT dysfunction, whereas non-obese HFDoff had hyperglycemia and SAT hypermetabolism. In the caecum, unclassified Rikenellaceae (10-fold enrichment in MIO-HFDoff) and Clostridiales genera (4-fold deficiency in MIOR-HFDoff) were important discriminators of these two phenotypes. In conclusion, SAT whitening is an early abnormality in the offspring of HFD dams. In adult life, maternal HFD and the induced excessive food intake translates into a dimorphic phenotype involving SAT, BAT, and microbiota distinctively, reflecting maternal diet*sex interaction. This helps explain inter-individual variability in fetal programming and the higher rates of type 2 diabetes observed in adult women born to obese mothers, supporting personalized risk assessment, prevention, and treatment.
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Affiliation(s)
- Maria Angela Guzzardi
- Institute of Clinical Physiology, National Research Council (CNR), 56124 Pisa, Italy
| | - Maria Carmen Collado
- Institute of Agrochemistry and Food Technology, National Research Council (IATA-CSIC), 46980 Valencia, Spain
| | - Daniele Panetta
- Institute of Clinical Physiology, National Research Council (CNR), 56124 Pisa, Italy
| | - Maria Tripodi
- Institute of Clinical Physiology, National Research Council (CNR), 56124 Pisa, Italy
| | - Patricia Iozzo
- Institute of Clinical Physiology, National Research Council (CNR), 56124 Pisa, Italy
- Correspondence: ; Tel.: +39-050-3152789
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12
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Takeda Y, Dai P. Chronic Fatty Acid Depletion Induces Uncoupling Protein 1 (UCP1) Expression to Coordinate Mitochondrial Inducible Proton Leak in a Human-Brown-Adipocyte Model. Cells 2022; 11:cells11132038. [PMID: 35805122 PMCID: PMC9265531 DOI: 10.3390/cells11132038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 06/23/2022] [Accepted: 06/25/2022] [Indexed: 11/17/2022] Open
Abstract
Thermogenic brown fat contributes to metabolic health in adult humans. Obese conditions are known to repress adipose-tissue browning and its activity. Herein, we found that chronic fatty acid (FA) depletion induced uncoupling protein 1 (UCP1) expression in the chemical-compound-induced brown adipocytes (ciBAs). The ciBAs, converted from human dermal fibroblasts under FA-free conditions, had low intracellular triglyceride levels and strongly activated UCP1 expression. Prolonged treatment with carnitine also reduced triglyceride accumulation and induced UCP1 expression. Transcriptome analysis revealed that the UCP1 induction was accompanied by the activation of lipid metabolic genes. The FA-depleted conditions repressed mitochondrial proton-leak activity and mitochondrial membrane potential (MMP), despite maintaining a high UCP1 expression. The evidence suggested that UCP1 expression was induced to compensate for the proton-leak activity under low MMP. Our study reports a regulatory mechanism underlying UCP1 expression and mitochondrial-energy status in human brown adipocytes under different nutritional conditions.
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Affiliation(s)
- Yukimasa Takeda
- Correspondence: (Y.T.); (P.D.); Tel.: +81-75-251-5444 (Y.T.); +81-75-251-5135 (P.D.)
| | - Ping Dai
- Correspondence: (Y.T.); (P.D.); Tel.: +81-75-251-5444 (Y.T.); +81-75-251-5135 (P.D.)
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13
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Frankl JA, An Y, Sherwood A, Hao G, Huang FY, Thapa P, Clegg DJ, Sun X, Scherer PE, Öz OK. Comparison of BMIPP-SPECT/CT to 18FDG-PET/CT for Imaging Brown or Browning Fat in a Preclinical Model. Int J Mol Sci 2022; 23:4880. [PMID: 35563272 PMCID: PMC9101718 DOI: 10.3390/ijms23094880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/14/2022] [Accepted: 04/25/2022] [Indexed: 11/17/2022] Open
Abstract
Obesity is a leading cause of preventable death and morbidity. To elucidate the mechanisms connecting metabolically active brown adipose tissue (BAT) and metabolic health may provide insights into methods of treatment for obesity-related conditions. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18FDG-PET/CT) is traditionally used to image human BAT activity. However, the primary energy source of BAT is derived from intracellular fatty acids and not glucose. Beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) is a fatty acid analogue amenable to in vivo imaging by single photon emission computed tomography/CT (SPECT/CT) when radiolabeled with iodine isotopes. In this study, we compare the use of 18FDG-PET/CT and 125I-BMIPP-SPECT/CT for fat imaging to ascertain whether BMIPP is a more robust candidate for the non-invasive evaluation of metabolically active adipose depots. Interscapular BAT, inguinal white adipose tissue (iWAT), and gonadal white adipose tissue (gWAT) uptake of 18FDG and 125I-BMIPP was quantified in mice following treatment with the BAT-stimulating drug CL-316,243 or saline vehicle control. After CL-316,243 treatment, uptake of both radiotracers increased in BAT and iWAT. The standard uptake value (SUVmean) for 18FDG and 125I-BMIPP significantly correlated in these depots, although uptake of 125I-BMIPP in BAT and iWAT more closely mimicked the fold-change in metabolic rate as measured by an extracellular flux analyzer. Herein, we find that imaging BAT with the radioiodinated fatty acid analogue BMIPP yields more physiologically relevant data than 18FDG-PET/CT, and its conventional use may be a pivotal tool for evaluating BAT in both mice and humans.
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Affiliation(s)
- Joseph A. Frankl
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA; (J.A.F.); (A.S.); (G.H.); (P.T.); (X.S.)
| | - Yu An
- Department of Anesthesiology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA;
| | - Amber Sherwood
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA; (J.A.F.); (A.S.); (G.H.); (P.T.); (X.S.)
| | - Guiyang Hao
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA; (J.A.F.); (A.S.); (G.H.); (P.T.); (X.S.)
| | - Feng-Yun Huang
- Department of Medical Imaging and Radiological Sciences, Central Taiwan University of Science and Technology, No. 666, Buzih Road, Beitun District, Taichung City 406053, Taiwan;
| | - Pawan Thapa
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA; (J.A.F.); (A.S.); (G.H.); (P.T.); (X.S.)
| | - Deborah J. Clegg
- Department of Internal Medicine, Texas Tech Health Sciences Center, 5001 El Paso Dr, El Paso, TX 79905, USA;
| | - Xiankai Sun
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA; (J.A.F.); (A.S.); (G.H.); (P.T.); (X.S.)
| | - Philipp E. Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, Southwestern Medical Center, University of Texas, 5323 Harry Hines Blvd, Dallas, TX 75390, USA;
| | - Orhan K. Öz
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA; (J.A.F.); (A.S.); (G.H.); (P.T.); (X.S.)
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14
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Akalestou E, Miras AD, Rutter GA, le Roux CW. Mechanisms of Weight Loss After Obesity Surgery. Endocr Rev 2022; 43:19-34. [PMID: 34363458 PMCID: PMC8755990 DOI: 10.1210/endrev/bnab022] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Indexed: 02/07/2023]
Abstract
Obesity surgery remains the most effective treatment for obesity and its complications. Weight loss was initially attributed to decreased energy absorption from the gut but has since been linked to reduced appetitive behavior and potentially increased energy expenditure. Implicated mechanisms associating rearrangement of the gastrointestinal tract with these metabolic outcomes include central appetite control, release of gut peptides, change in microbiota, and bile acids. However, the exact combination and timing of signals remain largely unknown. In this review, we survey recent research investigating these mechanisms, and seek to provide insights on unanswered questions over how weight loss is achieved following bariatric surgery which may eventually lead to safer, nonsurgical weight-loss interventions or combinations of medications with surgery.
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Affiliation(s)
- Elina Akalestou
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Alexander D Miras
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.,Lee Kong Chian Imperial Medical School, Nanyang Technological University, Singapore.,University of Montreal Hospital Research Centre, Montreal, QC, Canada
| | - Carel W le Roux
- Diabetes Complications Research Centre, University College Dublin, Ireland.,Diabetes Research Group, School of Biomedical Science, Ulster University, Belfast, UK
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15
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Choi KM, Kim JH, Kong X, Isik M, Zhang J, Lim HW, Yoon JC. Defective brown adipose tissue thermogenesis and impaired glucose metabolism in mice lacking Letmd1. Cell Rep 2021; 37:110104. [PMID: 34910916 DOI: 10.1016/j.celrep.2021.110104] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 09/30/2021] [Accepted: 11/15/2021] [Indexed: 12/13/2022] Open
Abstract
Manipulation of energy-dissipating adipocytes has the potential to produce metabolic benefits. To this end, it is valuable to understand the mechanisms controlling the generation and function of thermogenic fat. Here, we identify Letm1 domain containing 1 (Letmd1) as a regulator of brown fat formation and function. The expression of Letmd1 is induced in brown fat by cold exposure and by β-adrenergic activation. Letmd1-deficient mice exhibit severe cold intolerance concomitant with abnormal brown fat morphology, reduced thermogenic gene expression, and low mitochondrial content. The null mice exhibit impaired β3-adrenoreceptor-dependent thermogenesis and are prone to diet-induced obesity and defective glucose disposal. Letmd1 was previously described as a mitochondrial protein, and we find that it also localizes to the nucleus and interacts with the transcriptional coregulator and chromatin remodeler Brg1/Smarca4, thus providing a way to impact thermogenic gene expression. Our study uncovers a role for Letmd1 as a key regulatory component of adaptive thermogenesis.
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Affiliation(s)
- Kyung-Mi Choi
- Division of Endocrinology, Department of Internal Medicine, University of California Davis School of Medicine, Davis, CA 95616, USA
| | - Jung Hak Kim
- Division of Endocrinology, Department of Internal Medicine, University of California Davis School of Medicine, Davis, CA 95616, USA
| | - Xiangmudong Kong
- Department of Surgical and Radiological Sciences, University of California Davis School of Veterinary Medicine, Davis, CA 95616, USA
| | | | - Jin Zhang
- Department of Surgical and Radiological Sciences, University of California Davis School of Veterinary Medicine, Davis, CA 95616, USA
| | - Hee-Woong Lim
- Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - John C Yoon
- Division of Endocrinology, Department of Internal Medicine, University of California Davis School of Medicine, Davis, CA 95616, USA.
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16
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Lee GH, Peng C, Jeong SY, Park SA, Lee HY, Hoang TH, Kim J, Chae HJ. Ginger extract controls mTOR-SREBP1-ER stress-mitochondria dysfunction through AMPK activation in obesity model. J Funct Foods 2021. [DOI: 10.1016/j.jff.2021.104628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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17
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Akalestou E, Suba K, Lopez-Noriega L, Georgiadou E, Chabosseau P, Gallie A, Wretlind A, Legido-Quigley C, Leclerc I, Salem V, Rutter GA. Intravital imaging of islet Ca 2+ dynamics reveals enhanced β cell connectivity after bariatric surgery in mice. Nat Commun 2021; 12:5165. [PMID: 34453049 PMCID: PMC8397709 DOI: 10.1038/s41467-021-25423-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/06/2021] [Indexed: 11/25/2022] Open
Abstract
Bariatric surgery improves both insulin sensitivity and secretion and can induce diabetes remission. However, the mechanisms and time courses of these changes, particularly the impact on β cell function, are difficult to monitor directly. In this study, we investigated the effect of Vertical Sleeve Gastrectomy (VSG) on β cell function in vivo by imaging Ca2+ dynamics in islets engrafted into the anterior eye chamber. Mirroring its clinical utility, VSG in mice results in significantly improved glucose tolerance, and enhanced insulin secretion. We reveal that these benefits are underpinned by augmented β cell function and coordinated activity across the islet. These effects involve changes in circulating GLP-1 levels which may act both directly and indirectly on the β cell, in the latter case through changes in body weight. Thus, bariatric surgery leads to time-dependent increases in β cell function and intra-islet connectivity which are likely to contribute to diabetes remission.
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Affiliation(s)
- Elina Akalestou
- grid.413629.b0000 0001 0705 4923Section of Cell Biology and Functional Genomics, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Kinga Suba
- grid.413629.b0000 0001 0705 4923Section of Cell Biology and Functional Genomics, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Livia Lopez-Noriega
- grid.413629.b0000 0001 0705 4923Section of Cell Biology and Functional Genomics, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Eleni Georgiadou
- grid.413629.b0000 0001 0705 4923Section of Cell Biology and Functional Genomics, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Pauline Chabosseau
- grid.413629.b0000 0001 0705 4923Section of Cell Biology and Functional Genomics, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Alasdair Gallie
- grid.413629.b0000 0001 0705 4923Central Biological Services (CBS) Hammersmith Hospital Campus, London, UK
| | - Asger Wretlind
- grid.419658.70000 0004 0646 7285Systems Medicine, Steno Diabetes Center, Gentofte, Copenhagen, Denmark
| | - Cristina Legido-Quigley
- grid.419658.70000 0004 0646 7285Systems Medicine, Steno Diabetes Center, Gentofte, Copenhagen, Denmark
| | - Isabelle Leclerc
- grid.413629.b0000 0001 0705 4923Section of Cell Biology and Functional Genomics, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Victoria Salem
- grid.413629.b0000 0001 0705 4923Section of Cell Biology and Functional Genomics, Imperial College London, Hammersmith Hospital Campus, London, UK ,grid.413629.b0000 0001 0705 4923Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Guy A. Rutter
- grid.413629.b0000 0001 0705 4923Section of Cell Biology and Functional Genomics, Imperial College London, Hammersmith Hospital Campus, London, UK ,grid.59025.3b0000 0001 2224 0361Lee Kong Chian Imperial Medical School, Nanyang Technological University, Singapore, Singapore ,grid.14848.310000 0001 2292 3357Centre de Recherches du CHUM, University of Montreal, Montreal, QC Canada
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18
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Bini J, Norcross M, Cheung M, Duffy A. The Role of Positron Emission Tomography in Bariatric Surgery Research: a Review. Obes Surg 2021; 31:4592-4606. [PMID: 34304378 DOI: 10.1007/s11695-021-05576-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/24/2021] [Accepted: 06/30/2021] [Indexed: 12/15/2022]
Abstract
Bariatric surgery, initially understood as restricting or bypassing the amount of food that reaches the stomach to reduce food intake and/or increase malabsorption of food to promote weight loss, is now recognized to also affect incretin signaling in the gut and promote improvements in system-wide metabolism. Positron emission tomography (PET) is an imaging technique whereby patients are injected with picomolar concentrations of radioactive molecules, below the threshold of having physiological effects, to measure spatial distributions of blood flow, metabolism, receptor, and enzyme pharmacology. Recent advances in both whole-body PET imaging and radioligand development will allow for novel research that may help clarify the roles of peripheral and central receptor/enzyme systems in treating obesity with bariatric surgery.
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Affiliation(s)
- Jason Bini
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, 801 Howard Avenue, PO Box 208048, New Haven, CT, USA.
| | | | - Maija Cheung
- Department of Surgery, Yale University School of Medicine, New Haven, CT, USA
| | - Andrew Duffy
- Department of Surgery, Yale University School of Medicine, New Haven, CT, USA
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19
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McNeill BT, Suchacki KJ, Stimson RH. MECHANISMS IN ENDOCRINOLOGY: Human brown adipose tissue as a therapeutic target: warming up or cooling down? Eur J Endocrinol 2021; 184:R243-R259. [PMID: 33729178 PMCID: PMC8111330 DOI: 10.1530/eje-20-1439] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 03/10/2021] [Indexed: 12/12/2022]
Abstract
Excessive accumulation of white adipose tissue leads to obesity and its associated metabolic health consequences such as type 2 diabetes and cardiovascular disease. Several approaches to treat or prevent obesity including public health interventions, surgical weight loss, and pharmacological approaches to reduce caloric intake have failed to substantially modify the increasing prevalence of obesity. The (re-)discovery of active brown adipose tissue (BAT) in adult humans approximately 15 years ago led to a resurgence in research into whether BAT activation could be a novel therapy for the treatment of obesity. Upon cold stimulus, BAT activates and generates heat to maintain body temperature, thus increasing energy expenditure. Activation of BAT may provide a unique opportunity to increase energy expenditure without the need for exercise. However, much of the underlying mechanisms surrounding BAT activation are still being elucidated and the effectiveness of BAT as a therapeutic target has not been realised. Research is ongoing to determine how best to expand BAT mass and activate existing BAT; approaches include cold exposure, pharmacological stimulation using sympathomimetics, browning agents that induce formation of thermogenic beige adipocytes in white adipose depots, and the identification of factors secreted by BAT with therapeutic potential. In this review, we discuss the caloric capacity and other metabolic benefits from BAT activation in humans and the role of metabolic tissues such as skeletal muscle in increasing energy expenditure. We discuss the potential of current approaches and the challenges of BAT activation as a novel strategy to treat obesity and metabolic disorders.
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Affiliation(s)
- Ben T McNeill
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen’s Medical Research Institute, Edinburgh, UK
| | - Karla J Suchacki
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen’s Medical Research Institute, Edinburgh, UK
| | - Roland H Stimson
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen’s Medical Research Institute, Edinburgh, UK
- Correspondence should be addressed to R H Stimson Email
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20
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Piquer-Garcia I, Cereijo R, Corral-Pérez J, Pellitero S, Martínez E, Taxerås SD, Tarascó J, Moreno P, Balibrea J, Puig-Domingo M, Serra D, Herrero L, Jiménez-Pavón D, Lerin C, Villarroya F, Sánchez-Infantes D. Use of Infrared Thermography to Estimate Brown Fat Activation After a Cooling Protocol in Patients with Severe Obesity That Underwent Bariatric Surgery. Obes Surg 2021; 30:2375-2381. [PMID: 32133589 DOI: 10.1007/s11695-020-04502-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND In contrast to the energy-storing role of white adipose tissue (WAT), brown adipose tissue (BAT) acts as the main site of non-shivering thermogenesis in mammals and has been reported to play a role in protection against obesity and associated metabolic alterations in rodents. Infrared thermography (IRT) has been proposed as a novel non-invasive, safe, and quick method to estimate BAT thermogenic activation in humans. The aim of this study is to determine whether the IRT could be a potential new tool to estimate BAT thermogenic activation in patients with severe obesity in response to bariatric surgery. METHODS Supraclavicular BAT thermogenic activation was evaluated using IRT in a cohort of 31 patients (50 ± 10 years old, BMI = 44.5 ± 7.8; 15 undergoing laparoscopy sleeve gastrectomy and 16 Roux-en-Y gastric bypass) at baseline and 6 months after a bariatric surgery. Clinical parameters were determined at these same time points. RESULTS Supraclavicular BAT-related activity was detected in our patients by IRT after a cooling stimulus. The BAT thermogenic activation was higher at 6 months after laparoscopy sleeve gastrectomy (0.06 ± 0.1 vs 0.32 ± 0.1), while patients undergoing to a roux-en-Y gastric bypass did not change their thermogenic response using the same cooling stimulus (0.09 ± 0.1 vs 0.08 ± 0.1). CONCLUSIONS Our study postulates the IRT as a potential tool to evaluate BAT thermogenic activation in patients with obesity before and after a bariatric surgery. Further studies are needed to evaluate differences between LSG technique and RYGB on BAT activation.
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Affiliation(s)
| | - Rubén Cereijo
- Department of Biochemistry and Molecular Biomedicine, and Institute of Biomedicine, University of Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Juan Corral-Pérez
- MOVE-IT Research Group and Department of Physical Education, Faculty of Education Sciences, University of Cádiz, Cadiz, Spain.,Institute of Research and Innovation in Biomedical Sciences of the Province of Cádiz (INiBICA), University of Cádiz, Cadiz, Spain
| | - Silvia Pellitero
- Germans Trias i Pujol Research Institute, Barcelona, Spain.,Centro de Investigación Biomédica en Fisiopatología de la Diabetes y enfermedades metabólicas (CIBERDEM), ISCIII, Madrid, Spain
| | - Eva Martínez
- Germans Trias i Pujol Research Institute, Barcelona, Spain
| | - Siri D Taxerås
- Germans Trias i Pujol Research Institute, Barcelona, Spain
| | - Jordi Tarascó
- Germans Trias i Pujol Research Institute, Barcelona, Spain
| | - Pau Moreno
- Germans Trias i Pujol Research Institute, Barcelona, Spain
| | - José Balibrea
- Metabolic and Bariatric Surgery Unit, EAC-BS Center of Excellence, Vall d'Hebron University Hospital, Barcelona, Spain
| | - Manel Puig-Domingo
- Germans Trias i Pujol Research Institute, Barcelona, Spain.,Centro de Investigación Biomédica en Fisiopatología de la Diabetes y enfermedades metabólicas (CIBERDEM), ISCIII, Madrid, Spain
| | - Dolors Serra
- Centro de Investigación Biomédica de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029, Madrid, Spain.,Department of Biochemistry and Physiology, School of Pharmacy, Institut de Biomedicina de la Universitat de Barcelona (IBUB),, Universitat de Barcelona, 08028, Barcelona, Spain
| | - Laura Herrero
- Centro de Investigación Biomédica de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029, Madrid, Spain.,Department of Biochemistry and Physiology, School of Pharmacy, Institut de Biomedicina de la Universitat de Barcelona (IBUB),, Universitat de Barcelona, 08028, Barcelona, Spain
| | - David Jiménez-Pavón
- MOVE-IT Research Group and Department of Physical Education, Faculty of Education Sciences, University of Cádiz, Cadiz, Spain.,Institute of Research and Innovation in Biomedical Sciences of the Province of Cádiz (INiBICA), University of Cádiz, Cadiz, Spain
| | - Carles Lerin
- Endocrinology department, Institut de Recerca Sant Joan de Déu, 08950, Barcelona, Spain
| | - Francesc Villarroya
- Department of Biochemistry and Molecular Biomedicine, and Institute of Biomedicine, University of Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - David Sánchez-Infantes
- Germans Trias i Pujol Research Institute, Barcelona, Spain. .,Centro de Investigación Biomédica de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029, Madrid, Spain. .,Germans Trias i Pujol Research Institute (IGTP), Campus Can Ruti, Carretera de Can Ruti, Camí de les Escoles s/n, Badalona, 08916, Barcelona, Spain.
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21
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Ceglarek VM, Bertasso IM, Pietrobon CB, Scomazzon SP, Leite NC, Bonfleur ML, Araújo ACF, Balbo SL, Grassiolli S. Maternal Roux-en-Y gastric bypass surgery reduces lipid deposition and increases UCP1 expression in the brown adipose tissue of male offspring. Sci Rep 2021; 11:1158. [PMID: 33441773 PMCID: PMC7806700 DOI: 10.1038/s41598-020-80104-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 12/03/2020] [Indexed: 01/22/2023] Open
Abstract
Maternal obesity induced by cafeteria diet (CAF) predisposes offspring to obesity and metabolic diseases, events that could be avoided by maternal bariatric surgery (BS). Herein we evaluated whether maternal BS is able to modulate brown adipose tissue (BAT) morphology and function in adult male rats born from obese female rats submitted to Roux-en-Y gastric bypass (RYGB). For this, adult male rat offspring were obtained from female rats that consumed standard diet (CTL), or CAF diet, and were submitted to simulated operation or RYGB. Analysis of offspring showed that, at 120 days of life, the maternal CAF diet induced adiposity and decreased the expression of mitochondrial Complex I (CI) and Complex III (CIII) in the BAT, resulting in higher accumulation of lipids than in BAT from offspring of CTL dams. Moreover, maternal RYGB increased UCP1 expression and prevented excessive deposition of lipids in the BAT of adult male offspring rats. However, maternal RYGB failed to reverse the effects of maternal diet on CI and CIII expression. Thus, maternal CAF promotes higher lipid deposition in the BAT of offspring, contributing to elevated adiposity. Maternal RYGB prevented obesity in offspring, probably by increasing the expression of UCP1.
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Affiliation(s)
- Vanessa Marieli Ceglarek
- Laboratory of Endocrine and Metabolic Physiology, Biosciences and Health, Postgraduate, University of West Parana, Cascavel, PR, Brazil. .,Institute of Basic Health Sciences. Biological Sciences: Physiology, postgraduate. Department of Physiology, Room 337-7, Laboratory of Neurophysiology of Cognition and Development of the Brain, Federal University of Rio Grande do Sul, 500, Sarmento Leite - Farroupilha, Porto Alegre, RS, 90050-170, Brazil.
| | - Iala Milene Bertasso
- Laboratory of Endocrine and Metabolic Physiology, Biosciences and Health, Postgraduate, University of West Parana, Cascavel, PR, Brazil
| | - Carla Bruna Pietrobon
- Laboratory of Endocrine and Metabolic Physiology, Biosciences and Health, Postgraduate, University of West Parana, Cascavel, PR, Brazil
| | - Sofia Pizzato Scomazzon
- Medical Sciences: Endocrinology Post Graduate Program, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Nayara Carvalho Leite
- Obesity Comorbidities and Research Center, University of Campinas, Campinas, SP, Brazil
| | - Maria Lúcia Bonfleur
- Laboratory of Endocrine and Metabolic Physiology, Biosciences and Health, Postgraduate, University of West Parana, Cascavel, PR, Brazil
| | - Allan Cezar Faria Araújo
- Laboratory of Endocrine and Metabolic Physiology, Biosciences and Health, Postgraduate, University of West Parana, Cascavel, PR, Brazil
| | - Sandra Lucinei Balbo
- Laboratory of Endocrine and Metabolic Physiology, Biosciences and Health, Postgraduate, University of West Parana, Cascavel, PR, Brazil
| | - Sabrina Grassiolli
- Laboratory of Endocrine and Metabolic Physiology, Biosciences and Health, Postgraduate, University of West Parana, Cascavel, PR, Brazil
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22
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Dadson P, Rebelos E, Honka H, Juárez-Orozco LE, Kalliokoski KK, Iozzo P, Teuho J, Salminen P, Pihlajamäki J, Hannukainen JC, Nuutila P. Change in abdominal, but not femoral subcutaneous fat CT-radiodensity is associated with improved metabolic profile after bariatric surgery. Nutr Metab Cardiovasc Dis 2020; 30:2363-2371. [PMID: 32919861 DOI: 10.1016/j.numecd.2020.07.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS Computed tomography (CT)-derived adipose tissue radiodensity represents a potential noninvasive surrogate marker for lipid deposition and obesity-related metabolic disease risk. We studied the effects of bariatric surgery on CT-derived adipose radiodensities in abdominal and femoral areas and their relationships to circulating metabolites in morbidly obese patients. METHODS AND RESULTS We examined 23 morbidly obese women who underwent CT imaging before and 6 months after bariatric surgery. Fifteen healthy non-obese women served as controls. Radiodensities of the abdominal subcutaneous (SAT) and visceral adipose tissue (VAT), and the femoral SAT, adipose tissue masses were measured in all participants. Circulating metabolites were measured by NMR. At baseline, radiodensities of abdominal fat depots were lower in the obese patients as compared to the controls. Surprisingly, radiodensity of femoral SAT was higher in the obese as compared to the controls. In the abdominal SAT depot, radiodensity strongly correlated with SAT mass (r = -0.72, p < 0.001). After surgery, the radiodensities of abdominal fat increased significantly (both p < 0.01), while femoral SAT radiodensity remained unchanged. Circulating ApoB/ApoA-I, leucine, valine, and GlycA decreased, while glycine levels significantly increased as compared to pre-surgical values (all p < 0.05). The increase in abdominal fat radiodensity correlated negatively with the decreased levels of ApoB/ApoA-I ratio, leucine and GlycA (all p < 0.05). The increase in abdominal SAT density was significantly correlated with the decrease in the fat depot mass (r = -0.66, p = 0.002). CONCLUSION Higher lipid content in abdominal fat depots, and lower content in femoral subcutaneous fat, constitute prominent pathophysiological features in morbid obesity. Further studies are needed to clarify the role of non-abdominal subcutaneous fat in the pathogenesis of obesity. CLINICAL TRIAL REGISTRATION NUMBER NCT01373892.
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Affiliation(s)
- Prince Dadson
- Turku PET Centre, University of Turku, Turku, Finland
| | - Eleni Rebelos
- Turku PET Centre, University of Turku, Turku, Finland
| | - Henri Honka
- Turku PET Centre, University of Turku, Turku, Finland
| | | | | | - Patricia Iozzo
- Institute of Clinical Physiology, National Research Council (CNR), Pisa, Italy
| | - Jarmo Teuho
- Turku PET Centre, University of Turku, Turku, Finland; Turku PET Centre, Turku University Hospital, Turku, Finland
| | - Paulina Salminen
- Division of Digestive Surgery and Urology, Turku University Hospital, Turku, Finland; Department of Surgery, University of Turku, Turku, Finland
| | - Jussi Pihlajamäki
- Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland; Clinical Nutrition and Obesity Centre, Kuopio University Hospital, Kuopio, Finland
| | - Jarna C Hannukainen
- Turku PET Centre, University of Turku, Turku, Finland; Turku PET Centre, Turku University Hospital, Turku, Finland
| | - Pirjo Nuutila
- Turku PET Centre, University of Turku, Turku, Finland; Department of Endocrinology, Turku University Hospital, Turku, Finland.
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23
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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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24
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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.
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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.
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25
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Moffett RC, Docherty NG, le Roux CW. The altered enteroendocrine reportoire following roux-en-Y-gastric bypass as an effector of weight loss and improved glycaemic control. Appetite 2020; 156:104807. [PMID: 32871202 DOI: 10.1016/j.appet.2020.104807] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/14/2020] [Accepted: 07/20/2020] [Indexed: 02/08/2023]
Abstract
The alarming rise in obesity and relative lack of pharmacotherapies to treat, what is becoming a global epidemic, has necessitated that an increasing number of bariatric procedures be performed. Several surgical techniques have been developed during the last 50 years and the advent of laparoscopic surgery has increased the safety and efficacy of these procedures. Bariatric surgery is by a substantial margin, the most efficacious means of achieving sustained weight loss maintenance in patients with obesity. Roux-en-Y gastric bypass surgery (RYGB) elicits the most favourable metabolic outcomes with attendant benefits for type 2 diabetes and, cardiovascular disease as well as endocrine disorders and cancers in females. RYGB is the most extensively studied bariatric procedure regarding mechanism of action. In this review we catalogue the multiple alterations in secretion of gut hormones (ghrelin, obestatin, cholecystokinin, GLP-1, PYY, GIP, oxyntomodulin, glicentin and GLP-2) occurring after RYGB and summarise evidence indicating that these changes play a role in the reduction of food intake and improvements in glucose homeostasis.
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Affiliation(s)
- R Charlotte Moffett
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine, UK.
| | - Neil G Docherty
- Diabetes Complications Research Centre, Conway Institute, School of Medicine, University College Dublin, Ireland; Department of Gastrosurgical Research and Education, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Carel W le Roux
- Diabetes Complications Research Centre, Conway Institute, School of Medicine, University College Dublin, Ireland; Investigative Science, Imperial College London, UK
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26
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Ceglarek VM, Guareschi ZM, Moreira-Soares G, Ecker-Passarello RC, Balbo SL, Bonfleur ML, Grassiolli S. DUODENAL-JEJUNAL BYPASS REDUCES LIPID ACCUMULATION IN THE BROWN ADIPOSE TISSUE OF HYPOTHALAMIC OBESE RATS. ACTA ACUST UNITED AC 2020; 33:e1497. [PMID: 32667527 PMCID: PMC7357552 DOI: 10.1590/0102-672020190001e1497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 11/12/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Effects of duodenal-jejunal bypass surgery (DJB) on the proliferation of nuclei and the area of adipocytes in the brown adipose tissue of obese rats. Thermogenic activity in the brown adipose tissue (BAT) of obese individuals is reduced, and this condition may be modified by bariatric surgery (BS). AIM To characterize fat deposition in BAT from hypothalamic obese (HyO) rats submitted to duodenal-jejunal-bypass (DJB) surgery. METHODS For induction of hypothalamic obesity, newborn male Wistar rats were treated with subcutaneous injections of monosodium glutamate (MSG). The control (CTL) group received saline solution. At 90 days, the HyO rats were submitted to DJB or sham operation, generating the HyO-DJB and HyO-SHAM groups. At 270 days, the rats were euthanized, and the BAT was weighed and submitted to histological analysis. RESULTS Compared to BAT from CTL animals, the BAT from HyO-SHAM rats displayed increased weight, hypertrophy with greater lipid accumulation and a reduction in nucleus number. DJB effectively increased nucleus number and normalized lipid deposition in the BAT of HyO-SHAM rats, similar to that observed in CTL animals. CONCLUSION DJB surgery avoided excessive lipid deposition in the BAT of hypothalamic obese rats, suggesting that this procedure could reactivate thermogenesis in BAT, and contribute to increase energy expenditure.
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Affiliation(s)
- Vanessa Marieli Ceglarek
- Endocrine Physiology and Metabolism Laboratory, Center for Biological and Health Sciences, State University of Western Paraná, Cascavel, PR, Brazil
| | - Zoé Maria Guareschi
- Endocrine Physiology and Metabolism Laboratory, Center for Biological and Health Sciences, State University of Western Paraná, Cascavel, PR, Brazil
| | - Gabriela Moreira-Soares
- Endocrine Pancreas and Metabolism Laboratory, Department of Structural and Functional Biology, Institute of Biology, Campinas State University, Campinas, SP, Brazil
| | - Rafaela Cristiane Ecker-Passarello
- Endocrine Physiology and Metabolism Laboratory, Center for Biological and Health Sciences, State University of Western Paraná, Cascavel, PR, Brazil
| | - Sandra Lucinei Balbo
- Endocrine Physiology and Metabolism Laboratory, Center for Biological and Health Sciences, State University of Western Paraná, Cascavel, PR, Brazil
| | - Maria Lúcia Bonfleur
- Endocrine Physiology and Metabolism Laboratory, Center for Biological and Health Sciences, State University of Western Paraná, Cascavel, PR, Brazil
| | - Sabrina Grassiolli
- Endocrine Physiology and Metabolism Laboratory, Center for Biological and Health Sciences, State University of Western Paraná, Cascavel, PR, Brazil
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27
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Adami GF, Carbone F, Montecucco F, Camerini G, Cordera R. Adipose Tissue Composition in Obesity and After Bariatric Surgery. Obes Surg 2020; 29:3030-3038. [PMID: 31190263 DOI: 10.1007/s11695-019-04030-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The adipose tissue is a complex organ that regulates food intake and energy expenditure as well as induces low-grade inflammation. This review deals with changes in the composition and activity of the adipose organ after bariatric surgery, focusing on epicardial and ectopic fat and on relationships between white and brown adipose tissues. Postoperative improvements of ectopic fat and epicardial fat size and composition account for the metabolic recovery and the decreased cardiovascular risk. Following Roux-en-Y gastric bypass or biliopancreatic diversion, a proportional increase in the size and activity of the metabolically active brown adipose tissue was observed, most likely related to the postoperative rearrangement of the entero-hormonal pattern with an increase of GLP-1 production: this aspect would promote the postoperative weight loss and maintenance of post-surgery benefits.
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Affiliation(s)
- Gian Franco Adami
- Department of Internal Medicine, University of Genova, 8, viale Benedetto XV, 16132, Genova, Italy.
- IRCCS, Azienda Ospedale-Universitaria San Martino, Genoa, Italy.
| | - Federico Carbone
- Department of Internal Medicine, University of Genova, 8, viale Benedetto XV, 16132, Genova, Italy
- IRCCS, Azienda Ospedale-Universitaria San Martino, Genoa, Italy
| | - Fabrizio Montecucco
- Department of Internal Medicine, University of Genova, 8, viale Benedetto XV, 16132, Genova, Italy
- IRCCS, Azienda Ospedale-Universitaria San Martino, Genoa, Italy
| | - Giovanni Camerini
- Department of Internal Medicine, University of Genova, 8, viale Benedetto XV, 16132, Genova, Italy
- IRCCS, Azienda Ospedale-Universitaria San Martino, Genoa, Italy
- Department of Surgery, University of Genova, Genoa, Italy
| | - Renzo Cordera
- Department of Internal Medicine, University of Genova, 8, viale Benedetto XV, 16132, Genova, Italy
- IRCCS, Azienda Ospedale-Universitaria San Martino, Genoa, Italy
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28
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Hankir MK, Seyfried F. Do Bariatric Surgeries Enhance Brown/Beige Adipose Tissue Thermogenesis? Front Endocrinol (Lausanne) 2020; 11:275. [PMID: 32425889 PMCID: PMC7203442 DOI: 10.3389/fendo.2020.00275] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 04/14/2020] [Indexed: 12/13/2022] Open
Abstract
Bariatric surgeries induce marked and durable weight loss in individuals with morbid obesity through powerful effects on both food intake and energy expenditure. While alterations in gut-brain communication are increasingly implicated in the improved eating behavior following bariatric surgeries, less is known about the mechanistic basis for energy expenditure changes. Brown adipose tissue (BAT) and beige adipose tissue (BeAT) have emerged as major regulators of whole-body energy metabolism in humans as well as in rodents due to their ability to convert the chemical energy in circulating glucose and fatty acids into heat. In this Review, we critically discuss the steadily growing evidence from preclinical and clinical studies suggesting that Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG), the two most commonly performed bariatric surgeries, enhance BAT/BeAT thermogenesis. We address the documented mechanisms, highlight study limitations and finish by outlining unanswered questions in the subject. Further understanding how and to what extent bariatric surgeries enhance BAT/BeAT thermogenesis may not only aid in the development of improved obesity pharmacotherapies that safely and optimally target both sides of the energy balance equation, but also in the development of novel hyperglycemia and/or hyperlipidemia pharmacotherapies.
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Affiliation(s)
- Mohammed K. Hankir
- Department of Experimental Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Florian Seyfried
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
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29
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Frankl J, Sherwood A, Clegg DJ, Scherer PE, Öz OK. Imaging Metabolically Active Fat: A Literature Review and Mechanistic Insights. Int J Mol Sci 2019; 20:ijms20215509. [PMID: 31694216 PMCID: PMC6862590 DOI: 10.3390/ijms20215509] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 11/01/2019] [Accepted: 11/01/2019] [Indexed: 02/07/2023] Open
Abstract
Currently, obesity is one of the leading causes death in the world. Shortly before 2000, researchers began describing metabolically active adipose tissue on cancer-surveillance 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in adult humans. This tissue generates heat through mitochondrial uncoupling and functions similar to classical brown and beige adipose tissue in mice. Despite extensive research, human brown/beige fat's role in resistance to obesity in humans has not yet been fully delineated. FDG uptake is the de facto gold standard imaging technique when studying brown adipose tissue, although it has not been rigorously compared to other techniques. We, therefore, present a concise review of established and emerging methods to image brown adipose tissue activity in humans. Reviewed modalities include anatomic imaging with CT and magnetic resonance imaging (MRI); molecular imaging with FDG, fatty acids, and acetate; and emerging techniques. FDG-PET/CT is the most commonly used modality because of its widespread use in cancer imaging, but there are mechanistic reasons to believe other radiotracers may be more sensitive and accurate at detecting brown adipose tissue activity. Radiation-free modalities may help the longitudinal study of brown adipose tissue activity in the future.
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Affiliation(s)
- Joseph Frankl
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (J.F.); (A.S.)
| | - Amber Sherwood
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (J.F.); (A.S.)
| | - Deborah J. Clegg
- College of Nursing and Health Professions, Drexel University, 10th Floor, Room 1092, 1601 Cherry Street, Mail Stop 10501, Philadelphia, PA 19102, USA;
| | - Philipp E. Scherer
- Department of Internal Medicine, Touchstone Diabetes Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA;
| | - Orhan K. Öz
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (J.F.); (A.S.)
- Correspondence:
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30
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Bae J, Jang Y, Kim H, Mahato K, Schaecher C, Kim IM, Kim E, Ro SH. Arsenite exposure suppresses adipogenesis, mitochondrial biogenesis and thermogenesis via autophagy inhibition in brown adipose tissue. Sci Rep 2019; 9:14464. [PMID: 31594991 PMCID: PMC6783448 DOI: 10.1038/s41598-019-50965-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 09/20/2019] [Indexed: 01/23/2023] Open
Abstract
Arsenite, a trivalent form of arsenic, is an element that occurs naturally in the environment. Humans are exposed to high dose of arsenite through consuming arsenite-contaminated drinking water and food, and the arsenite can accumulate in the human tissues. Arsenite induces oxidative stress, which is linked to metabolic disorders such as obesity and diabetes. Brown adipocytes dissipating energy as heat have emerging roles for obesity treatment and prevention. Therefore, understanding the pathophysiological role of brown adipocytes can provide effective strategies delineating the link between arsenite exposure and metabolic disorders. Our study revealed that arsenite significantly reduced differentiation of murine brown adipocytes and mitochondrial biogenesis and respiration, leading to attenuated thermogenesis via decreasing UCP1 expression. Oral administration of arsenite in mice resulted in heavy accumulation in brown adipose tissue and suppression of lipogenesis, mitochondrial biogenesis and thermogenesis. Mechanistically, arsenite exposure significantly inhibited autophagy necessary for homeostasis of brown adipose tissue through suppression of Sestrin2 and ULK1. These results clearly confirm the emerging mechanisms underlying the implications of arsenite exposure in metabolic disorders.
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Affiliation(s)
- Jiyoung Bae
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA.,Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Yura Jang
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA.,Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Heejeong Kim
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA
| | - Kalika Mahato
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA
| | - Cameron Schaecher
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA.,College of Medicine, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Isaac M Kim
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA
| | - Eunju Kim
- Department of Mechanical and Materials Engineering, University of Nebraska, Lincoln, NE, 68588, USA
| | - Seung-Hyun Ro
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA.
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31
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Diverse repertoire of human adipocyte subtypes develops from transcriptionally distinct mesenchymal progenitor cells. Proc Natl Acad Sci U S A 2019; 116:17970-17979. [PMID: 31420514 PMCID: PMC6731669 DOI: 10.1073/pnas.1906512116] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Single-cell sequencing technologies have revealed an unexpectedly broad repertoire of cells required to mediate complex functions in multicellular organisms. Despite the multiple roles of adipose tissue in maintaining systemic metabolic homeostasis, adipocytes are thought to be largely homogenous with only 2 major subtypes recognized in humans so far. Here we report the existence and characteristics of 4 distinct human adipocyte subtypes, and of their respective mesenchymal progenitors. The phenotypes of these distinct adipocyte subtypes are differentially associated with key adipose tissue functions, including thermogenesis, lipid storage, and adipokine secretion. The transcriptomic signature of "brite/beige" thermogenic adipocytes reveals mechanisms for iron accumulation and protection from oxidative stress, necessary for mitochondrial biogenesis and respiration upon activation. Importantly, this signature is enriched in human supraclavicular adipose tissue, confirming that these cells comprise thermogenic depots in vivo, and explain previous findings of a rate-limiting role of iron in adipose tissue browning. The mesenchymal progenitors that give rise to beige/brite adipocytes express a unique set of cytokines and transcriptional regulators involved in immune cell modulation of adipose tissue browning. Unexpectedly, we also find adipocyte subtypes specialized for high-level expression of the adipokines adiponectin or leptin, associated with distinct transcription factors previously implicated in adipocyte differentiation. The finding of a broad adipocyte repertoire derived from a distinct set of mesenchymal progenitors, and of the transcriptional regulators that can control their development, provides a framework for understanding human adipose tissue function and role in metabolic disease.
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32
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Abstract
One of the biggest challenges in the management of obesity is the prevention of weight regain after successful weight loss. Weight regain after weight loss has large interindividual variation. Although many factors probably contribute to this variation, we hypothesize that variability in biological responses associated with weight loss-induced shrinking of subcutaneous adipocytes has an important role. In this Review, we show that weight loss-induced variations in cellular stress, extracellular matrix remodelling, inflammatory responses, adipokine secretion and lipolysis seem to be associated with the amount of weight that is regained after successful weight loss. Weight regain could therefore, at least in part, depend on a combination of these factors. Further research on the causality of these associations could aid the development of effective strategies to prevent weight regain after successful weight loss.
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Affiliation(s)
- Marleen A van Baak
- NUTRIM School for Nutrition and Translational Research in Metabolism, Department of Human Biology, Maastricht University, Maastricht, Netherlands.
| | - Edwin C M Mariman
- NUTRIM School for Nutrition and Translational Research in Metabolism, Department of Human Biology, Maastricht University, Maastricht, Netherlands
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33
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Carpentier AC, Blondin DP, Virtanen KA, Richard D, Haman F, Turcotte ÉE. Brown Adipose Tissue Energy Metabolism in Humans. Front Endocrinol (Lausanne) 2018; 9:447. [PMID: 30131768 PMCID: PMC6090055 DOI: 10.3389/fendo.2018.00447] [Citation(s) in RCA: 197] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 07/20/2018] [Indexed: 12/16/2022] Open
Abstract
The demonstration of metabolically active brown adipose tissue (BAT) in humans primarily using positron emission tomography coupled to computed tomography (PET/CT) with the glucose tracer 18-fluorodeoxyglucose (18FDG) has renewed the interest of the scientific and medical community in the possible role of BAT as a target for the prevention and treatment of obesity and type 2 diabetes (T2D). Here, we offer a comprehensive review of BAT energy metabolism in humans. Considerable advances in methods to measure BAT energy metabolism, including nonesterified fatty acids (NEFA), chylomicron-triglycerides (TG), oxygen, Krebs cycle rate, and intracellular TG have led to very good quantification of energy substrate metabolism per volume of active BAT in vivo. These studies have also shown that intracellular TG are likely the primary energy source of BAT upon activation by cold. Current estimates of BAT's contribution to energy expenditure range at the lower end of what would be potentially clinically relevant if chronically sustained. Yet, 18FDG PET/CT remains the gold-standard defining method to quantify total BAT volume of activity, used to calculate BAT's total energy expenditure. Unfortunately, BAT glucose metabolism better reflects BAT's insulin sensitivity and blood flow. It is now clear that most glucose taken up by BAT does not fuel mitochondrial oxidative metabolism and that BAT glucose uptake can therefore be disconnected from thermogenesis. Furthermore, BAT thermogenesis is efficiently recruited upon repeated cold exposure, doubling to tripling its total oxidative capacity, with reciprocal reduction of muscle thermogenesis. Recent data suggest that total BAT volume may be much larger than the typically observed 50-150 ml with 18FDG PET/CT. Therefore, the current estimates of total BAT thermogenesis, largely relying on total BAT volume using 18FDG PET/CT, may underestimate the true contribution of BAT to total energy expenditure. Quantification of the contribution of BAT to energy expenditure begs for the development of more integrated whole body in vivo methods.
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Affiliation(s)
- André C. Carpentier
- Division of Endocrinology, Department of Medicine, Centre de Recherche du CHUS, Université de Sherbrooke, Sherbrooke, QC, Canada
| | | | - Kirsi A. Virtanen
- Turku PET Centre, Turku University Hospital, Turku, Finland
- Institute of Public Health and Clinical Nutrition, University of Eastern Finland (UEF), Kuopio, Finland
| | - Denis Richard
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, QC, Canada
| | - François Haman
- Faculty of Health Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Éric E. Turcotte
- Department of Nuclear Medicine and Radiobiology, Centre de Recherche du CHUS, Université de Sherbrooke, Sherbrooke, QC, Canada
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Observed changes in brown, white, hepatic and pancreatic fat after bariatric surgery: Evaluation with MRI. Eur Radiol 2018; 29:849-856. [PMID: 30062524 DOI: 10.1007/s00330-018-5611-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 05/29/2018] [Accepted: 06/15/2018] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To study the change in brown and white adipose tissue (BAT and WAT), as well as fat content in the liver and pancreas, in patients with morbid obesity before and after bariatric surgery. METHODS Twelve patients with morbid obesity (F=8, M=4, age: 45.4 years (38.4-51.2), BMI: 35.2 kg/m2 (32.5-38.6)) underwent pre-op MRI at baseline and two post-op scans at 6-month and 12-month intervals after bariatric surgery. Co-registered water, fat, fat-fraction and T2* image series were acquired. Supraclavicular BAT and abdominal WAT were measured using in-house algorithms. Intrahepatic triglyceride (IHTG) was measured using MR spectroscopy and pancreatic fat was measured using a region-of-interest approach. Fat contents were compared between baseline and the first and second 6-month intervals using non-parametric analysis of Friedman's test and Wilcoxon's signed-rank test. Level of significance was selected at p=0.017 (0.05/3). Threshold of non-alcoholic fatty liver disease was set at 5.56%. RESULTS Results indicated that BMI (p=0.005), IHTG (p=0.005), and subcutaneous (p=0.005) and visceral adipose tissues (p=0.005) were significantly reduced 6 months after surgery. Pancreatic fat (p=0.009) was significantly reduced at 12 months. Most reduction became stable between the 6-month and 12-month interval. No significant difference was observed in BAT volume, fat-fraction and T2* values. CONCLUSION The results of this study suggest that bariatric surgery effectively reduced weight, mainly as a result of the reduction of abdominal WAT. Liver and pancreatic fat were deceased below the threshold possibly due to the reduction of free fatty acid. BAT volume, fat-fraction and T2* showed no significant changes, probably because surgery itself might not have altered the metabolic profile of the patients. KEY POINTS • No significant changes were observed in fat-fraction, T2* and volume of brown adipose tissue after bariatric surgery. • Non-alcoholic fatty liver disease was resolved after surgery. • Abdominal white fat and liver fat were significantly reduced 6 months after surgery and become stable between 6 and 12 months while pancreatic fat was significantly reduced between 0 and 12 months.
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