101
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Ponnalagu D, Singh H. Insights Into the Role of Mitochondrial Ion Channels in Inflammatory Response. Front Physiol 2020; 11:258. [PMID: 32327997 PMCID: PMC7160495 DOI: 10.3389/fphys.2020.00258] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/05/2020] [Indexed: 12/14/2022] Open
Abstract
Mitochondria are the source of many pro-inflammatory signals that cause the activation of the immune system and generate inflammatory responses. They are also potential targets of pro-inflammatory mediators, thus triggering a severe inflammatory response cycle. As mitochondria are a central hub for immune system activation, their dysfunction leads to many inflammatory disorders. Thus, strategies aiming at regulating mitochondrial dysfunction can be utilized as a therapeutic tool to cure inflammatory disorders. Two key factors that determine the structural and functional integrity of mitochondria are mitochondrial ion channels and transporters. They are not only important for maintaining the ionic homeostasis of the cell, but also play a role in regulating reactive oxygen species generation, ATP production, calcium homeostasis and apoptosis, which are common pro-inflammatory signals. The significance of the mitochondrial ion channels in inflammatory response is still not clearly understood and will need further investigation. In this article, we review the different mechanisms by which mitochondria can generate the inflammatory response as well as highlight how mitochondrial ion channels modulate these mechanisms and impact the inflammatory processes.
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Affiliation(s)
- Devasena Ponnalagu
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University, Wexner Medical Center, Columbus, OH, United States
| | - Harpreet Singh
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University, Wexner Medical Center, Columbus, OH, United States
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102
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ASK1 inhibits browning of white adipose tissue in obesity. Nat Commun 2020; 11:1642. [PMID: 32242025 PMCID: PMC7118089 DOI: 10.1038/s41467-020-15483-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 03/10/2020] [Indexed: 12/13/2022] Open
Abstract
Increasing energy expenditure via induction of adipose tissue browning has become an appealing strategy to treat obesity and associated metabolic complications. Herein, we identify adipocyte-expressed apoptosis signal-regulating kinase 1 (ASK1) as regulator of adipose tissue browning. High fat diet-fed adipocyte-specific ASK1 knockout mice reveal increased UCP1 protein levels in inguinal adipose tissue concomitant with elevated energy expenditure, reduced obesity and ameliorated glucose tolerance compared to control littermates. In addition, ASK1-depletion blunts LPS-mediated downregulation of isoproterenol-induced UCP1 in subcutaneous fat both in vitro and in vivo. Conversely, adipocyte-specific ASK1 overexpression in chow-fed mice attenuates cold-induced UCP1 protein levels in inguinal fat. Mechanistically, ASK1 phosphorylates interferon regulatory factor 3 (IRF3) resulting in reduced Ucp1 expression. Taken together, our studies unravel a role of ASK1 in mediating the inhibitory effect of caloric surplus or LPS-treatment on adipose tissue browning. Adipocyte ASK1 might be a pharmacological target to combat obesity and associated morbidities.
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103
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Majeed M, Majeed S, Nagabhushanam K, Lawrence L, Mundkur L. Garcinia indica extract standardized for 20% Garcinol reduces adipogenesis and high fat diet-induced obesity in mice by alleviating endoplasmic reticulum stress. J Funct Foods 2020. [DOI: 10.1016/j.jff.2020.103863] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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104
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Wu R, Yu W, Fu L, Li F, Jing J, Cui X, Wang S, Cao Q, Xue B, Shi H. Postnatal leptin surge is critical for the transient induction of the developmental beige adipocytes in mice. Am J Physiol Endocrinol Metab 2020; 318:E453-E461. [PMID: 31961706 PMCID: PMC7191411 DOI: 10.1152/ajpendo.00292.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Beige adipocytes have become a promising therapeutic target to combat obesity. Our senior author Dr. B. Xue previously discovered a transient but significant induction of beige adipocytes in mice during early postnatal development, which peaked at postnatal day (P) 20 and then disappeared thereafter. However, the physiological mechanism underlying the transient induction of the developmental beige cells remains mystery. Interestingly, there exists a postnatal surge of leptin in mice at P10 before the appearance of the developmental beige adipocytes. Given the neurotropic effect of leptin during neuronal development and its role in activating the sympathetic nervous system (SNS), we tested the hypothesis that postnatal leptin surge is required for the transient induction of developmental beige adipocytes through sympathetic innervation. Unlike wild-type (WT) mice that were able to acquire the developmentally induced beige adipocytes at P20, ob/ob mice had much less uncoupling protein 1 (UCP1)-positive multilocular cells in inguinal white adipose tissue at the same age. This was consistent with reduced expression of UCP1 mRNA and protein levels in white fat of ob/ob mice. In contrast, daily injection of ob/ob mice with leptin between P8 and P16, mimicking the postnatal leptin surge, largely rescued the ability of these mice to acquire the developmentally induced beige adipocytes at P20, which was associated with enhanced sympathetic nerve innervation assessed by whole mount adipose tissue immunostaining of tyrosine hydroxylase. Our data demonstrate that the postnatal leptin surge is essential for the developmentally induced beige adipocyte formation in mice, possibly through increasing sympathetic nerve innervation.
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Affiliation(s)
- Rui Wu
- School of Pharmacy, Zhejiang University of Technology, Hangzhou, Zhejiang, China
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Wenyan Yu
- School of Pharmacy, Zhejiang University of Technology, Hangzhou, Zhejiang, China
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Lizhi Fu
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Fenfen Li
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Jia Jing
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Xin Cui
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Shirong Wang
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Qiang Cao
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Bingzhong Xue
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Hang Shi
- Department of Biology, Georgia State University, Atlanta, Georgia
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105
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Sun C, Sakashita H, Kim J, Tang Z, Upchurch GM, Yao L, Berry WL, Griffin TM, Olson LE. Mosaic Mutant Analysis Identifies PDGFRα/PDGFRβ as Negative Regulators of Adipogenesis. Cell Stem Cell 2020; 26:707-721.e5. [PMID: 32229310 DOI: 10.1016/j.stem.2020.03.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 11/26/2019] [Accepted: 03/06/2020] [Indexed: 01/01/2023]
Abstract
Adipocyte progenitors (APs) express platelet-derived growth factor receptors (PDGFRs), PDGFRα and PDGFRβ. Elevated PDGFRα signaling inhibits adipogenesis and promotes fibrosis; however, the function of PDGFRs in APs remains unclear. We combined lineage tracing and functional analyses in a sequential dual-recombinase approach that creates mosaic Pdgfr mutant cells by Cre/lox recombination with a linked Flp/frt reporter to track individual cell fates. Using mosaic lineage labeling, we show that adipocytes are derived from the Pdgfra lineage during postnatal growth and adulthood. In contrast, adipocytes are only derived from the mosaic Pdgfrb lineage during postnatal growth. Functionally, postnatal mosaic deletion of PDGFRα enhances adipogenesis and adult deletion enhances β3-adrenergic-receptor-induced beige adipocyte formation. Mosaic deletion of PDGFRβ also enhances white, brown, and beige adipogenesis. These data show that both PDGFRs are cell-autonomous inhibitors of adipocyte differentiation and implicate downregulation of PDGF signaling as a critical event in the transition from AP to adipocyte.
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Affiliation(s)
- Chengyi Sun
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Hiromi Sakashita
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Jang Kim
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Zifeng Tang
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - G Michael Upchurch
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Longbiao Yao
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - William L Berry
- Department of Surgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Timothy M Griffin
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Lorin E Olson
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA.
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106
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Tamura Y, Tomiya S, Takegaki J, Kouzaki K, Tsutaki A, Nakazato K. Apple polyphenols induce browning of white adipose tissue. J Nutr Biochem 2020; 77:108299. [DOI: 10.1016/j.jnutbio.2019.108299] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 10/09/2019] [Accepted: 11/12/2019] [Indexed: 12/11/2022]
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107
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The role of ADP-ribose metabolism in metabolic regulation, adipose tissue differentiation, and metabolism. Genes Dev 2020; 34:321-340. [PMID: 32029456 PMCID: PMC7050491 DOI: 10.1101/gad.334284.119] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In this review, Szanto et al. summarize the metabolic regulatory roles of PARP enzymes and their associated pathologies. Poly(ADP-ribose) polymerases (PARPs or ARTDs), originally described as DNA repair factors, have metabolic regulatory roles. PARP1, PARP2, PARP7, PARP10, and PARP14 regulate central and peripheral carbohydrate and lipid metabolism and often channel pathological disruptive metabolic signals. PARP1 and PARP2 are crucial for adipocyte differentiation, including the commitment toward white, brown, or beige adipose tissue lineages, as well as the regulation of lipid accumulation. Through regulating adipocyte function and organismal energy balance, PARPs play a role in obesity and the consequences of obesity. These findings can be translated into humans, as evidenced by studies on identical twins and SNPs affecting PARP activity.
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108
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Nishikawa S, Hydo T, Aoyama H, Miyata R, Kumazawa S, Tsuda T. Artepillin C, a Key Component of Brazilian Propolis, Induces Thermogenesis in Inguinal White Adipose Tissue of Mice through a Creatine-Metabolism-Related Thermogenic Pathway. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:1007-1014. [PMID: 31914311 DOI: 10.1021/acs.jafc.9b07080] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Induction of beige adipocytes in white adipose tissue (WAT) is a potential therapeutic target for the treatment of obesity because beige adipocytes release excess energy via uncoupling-protein-1-associated thermogenesis. In this study, we investigated how artepillin C (ArtC) promotes thermogenesis in vivo. We demonstrated that 28 day administration of ArtC (10 mg/kg of body weight) to mice significantly induced thermogenesis in beige adipocytes in inguinal WAT (iWAT) and suppressed reductions in core body temperature induced by cold exposure at 4 °C. Moreover, ArtC-induced thermogenesis in iWAT was significantly inhibited by treatment with a creatine metabolism inhibitor, and ArtC significantly upregulated the expression of creatine-metabolism-related enzymes in the thermogenic pathway. These results indicate that ArtC induces thermogenesis in beige adipocytes in iWAT, and the observed ArtC-induced thermogenesis is associated with the creatine-metabolism-related thermogenic pathway, which is characteristically observed in beige adipocytes.
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Affiliation(s)
- Sho Nishikawa
- College of Bioscience and Biotechnology , Chubu University , 1200 Matsumoto-cho , Kasugai , Aichi 487-8501 , Japan
| | - Takuma Hydo
- College of Bioscience and Biotechnology , Chubu University , 1200 Matsumoto-cho , Kasugai , Aichi 487-8501 , Japan
| | - Hiroki Aoyama
- College of Bioscience and Biotechnology , Chubu University , 1200 Matsumoto-cho , Kasugai , Aichi 487-8501 , Japan
| | - Ryo Miyata
- Department of Food and Nutritional Sciences , University of Shizuoka , Suruga-ku, Shizuoka , Shizuoka 422-8526 , Japan
| | - Shigenori Kumazawa
- Department of Food and Nutritional Sciences , University of Shizuoka , Suruga-ku, Shizuoka , Shizuoka 422-8526 , Japan
| | - Takanori Tsuda
- College of Bioscience and Biotechnology , Chubu University , 1200 Matsumoto-cho , Kasugai , Aichi 487-8501 , Japan
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109
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Jastroch M, Seebacher F. Importance of adipocyte browning in the evolution of endothermy. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190134. [PMID: 31928187 DOI: 10.1098/rstb.2019.0134] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Endothermy changes the relationship between organisms and their environment fundamentally, and it is therefore of major ecological and evolutionary significance. Endothermy is characterized by non-shivering thermogenesis, that is metabolic heat production in the absence of muscular activity. In many eutherian mammals, brown adipose tissue (BAT) is an evolutionary innovation that facilitates non-shivering heat production in mitochondria by uncoupling food-derived substrate oxidation from chemical energy (ATP) production. Consequently, energy turnover is accelerated resulting in increased heat release. The defining characteristics of BAT are high contents of mitochondria and vascularization, and the presence of uncoupling protein 1. Recent insights, however, reveal that a range of stimuli such as exercise, diet and the immune system can cause the browning of white adipocytes, thereby increasing energy expenditure and heat production even in the absence of BAT. Here, we review the molecular mechanisms that cause browning of white adipose tissue, and their potential contribution to thermoregulation. The significance for palaeophysiology lies in the presence of adipose tissue and the mechanisms that cause its browning and uncoupling in all amniotes. Hence, adipocytes may have played a role in the evolution of endothermy beyond the more specific evolution of BAT in eutherians. This article is part of the theme issue 'Vertebrate palaeophysiology'.
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Affiliation(s)
- Martin Jastroch
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91 Stockholm, Sweden
| | - Frank Seebacher
- School of Life and Environmental Sciences A08, University of Sydney, Sydney, NSW 2006, Australia
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110
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Song A, Dai W, Jang MJ, Medrano L, Li Z, Zhao H, Shao M, Tan J, Li A, Ning T, Miller MM, Armstrong B, Huss JM, Zhu Y, Liu Y, Gradinaru V, Wu X, Jiang L, Scherer PE, Wang QA. Low- and high-thermogenic brown adipocyte subpopulations coexist in murine adipose tissue. J Clin Invest 2020; 130:247-257. [PMID: 31573981 PMCID: PMC6934193 DOI: 10.1172/jci129167] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 09/25/2019] [Indexed: 12/29/2022] Open
Abstract
Brown adipose tissue (BAT), as the main site of adaptive thermogenesis, exerts beneficial metabolic effects on obesity and insulin resistance. BAT has been previously assumed to contain a homogeneous population of brown adipocytes. Utilizing multiple mouse models capable of genetically labeling different cellular populations, as well as single-cell RNA sequencing and 3D tissue profiling, we discovered a brown adipocyte subpopulation with low thermogenic activity coexisting with the classical high-thermogenic brown adipocytes within the BAT. Compared with the high-thermogenic brown adipocytes, these low-thermogenic brown adipocytes had substantially lower Ucp1 and Adipoq expression, larger lipid droplets, and lower mitochondrial content. Functional analyses showed that, unlike the high-thermogenic brown adipocytes, the low-thermogenic brown adipocytes have markedly lower basal mitochondrial respiration, and they are specialized in fatty acid uptake. Upon changes in environmental temperature, the 2 brown adipocyte subpopulations underwent dynamic interconversions. Cold exposure converted low-thermogenic brown adipocytes into high-thermogenic cells. A thermoneutral environment had the opposite effect. The recruitment of high-thermogenic brown adipocytes by cold stimulation is not affected by high-fat diet feeding, but it does substantially decline with age. Our results revealed a high degree of functional heterogeneity of brown adipocytes.
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Affiliation(s)
- Anying Song
- Department of Molecular & Cellular Endocrinology, Diabetes & Metabolism Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Wenting Dai
- Department of Molecular & Cellular Endocrinology, Diabetes & Metabolism Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Min Jee Jang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA
| | - Leonard Medrano
- Department of Translational Research & Cellular Therapeutics, Diabetes & Metabolism Research Institute, and
| | - Zhuo Li
- Electron Microscopy and Atomic Force Microscopy Core, Beckman Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Hu Zhao
- Department of Restorative Sciences, School of Dentistry, Texas A&M University, Dallas, Texas, USA
| | - Mengle Shao
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jiayi Tan
- Department of Molecular & Cellular Endocrinology, Diabetes & Metabolism Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Aimin Li
- Pathology Core of Shared Resources and
| | - Tinglu Ning
- Department of Molecular & Cellular Endocrinology, Diabetes & Metabolism Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Marcia M. Miller
- Electron Microscopy and Atomic Force Microscopy Core, Beckman Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Brian Armstrong
- Light Microscopy Digital Imaging Core, Beckman Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Janice M. Huss
- Department of Molecular & Cellular Endocrinology, Diabetes & Metabolism Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Yi Zhu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Yong Liu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Institute for Advanced Studies, Wuhan University, Wuhan, China
| | - Viviana Gradinaru
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA
| | | | - Lei Jiang
- Department of Molecular & Cellular Endocrinology, Diabetes & Metabolism Research Institute, City of Hope Medical Center, Duarte, California, USA
- Comprehensive Cancer Center, Beckman Research Institute, City of Hope Medical Center, Duarte, California, USA
| | - Philipp E. Scherer
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Qiong A. Wang
- Department of Molecular & Cellular Endocrinology, Diabetes & Metabolism Research Institute, City of Hope Medical Center, Duarte, California, USA
- Comprehensive Cancer Center, Beckman Research Institute, City of Hope Medical Center, Duarte, California, USA
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111
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Ikeda K, Yamada T. UCP1 Dependent and Independent Thermogenesis in Brown and Beige Adipocytes. Front Endocrinol (Lausanne) 2020; 11:498. [PMID: 32849287 PMCID: PMC7399049 DOI: 10.3389/fendo.2020.00498] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 06/23/2020] [Indexed: 12/26/2022] Open
Abstract
Mammals have two types of thermogenic adipocytes: brown adipocytes and beige adipocytes. Thermogenic adipocytes express high levels of uncoupling protein 1 (UCP1) to dissipates energy in the form of heat by uncoupling the mitochondrial proton gradient from mitochondrial respiration. There is much evidence that UCP1 is the center of BAT thermogenesis and systemic energy homeostasis. Recently, UCP1 independent thermogenic pathway identified in thermogenic adipocytes. Importantly, the thermogenic pathways are different in brown and beige adipocytes. Ca2+-ATPase 2b calcium cycling mechanism is selective to beige adipocytes. It remains unknown how the multiple thermogenic mechanisms are coordinately regulated. The discovery of UCP1-independent thermogenic mechanisms potential offer new opportunities for improving obesity and type 2 diabetes particularly in groups such as elderly and obese populations who do not possess UCP1 positive adipocytes.
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112
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Abstract
Beige adipocytes, which consume energy mainly in an uncoupling protein 1 (UCP1)-dependent manner, are risen in white adipose tissue (WAT) depots. Since beige adipocyte development is gaining attention as a potential strategy for conquering obesity, worldwide researchers are making efforts to study its biological aspects. However, assessing UCP1 protein levels in beige adipocytes is challenging because of the high level of lipid contaminants in WAT. This study showed that an acetone precipitation method had advantages over conventional methods for eliminating lipid contaminants, achieving clear Western blot bands for WAT proteins, especially UCP1. Our results suggest that the acetone precipitation cleaning method could be useful for the clear analysis and precise evaluation of WAT proteins.
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Affiliation(s)
- Min-Jung Park
- Department of Veterinary Physiology, College of Veterinary Medicine, Chonnam National University, Gwangju, Korea
| | - Chang-Min Lee
- Department of Veterinary Laboratory Medicine, College of Veterinary Medicine, Chonnam National University, Gwangju, Korea
| | - Dong-il Kim
- Department of Veterinary Physiology, College of Veterinary Medicine, Chonnam National University, Gwangju, Korea
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113
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Fukuda A, Honda S, Fujioka N, Sekiguchi Y, Mizuno S, Miwa Y, Sugiyama F, Hayashi Y, Nishimura K, Hisatake K. Non-invasive in vivo imaging of UCP1 expression in live mice via near-infrared fluorescent protein iRFP720. PLoS One 2019; 14:e0225213. [PMID: 31730675 PMCID: PMC6857924 DOI: 10.1371/journal.pone.0225213] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 10/29/2019] [Indexed: 01/08/2023] Open
Abstract
Uncoupling protein 1 (UCP1) is a mitochondrial protein that is expressed in both brown and beige adipocytes. UCP1 uncouples the mitochondrial electron transport chain from ATP synthesis to produce heat via non-shivering thermogenesis. Due to their ability to dissipate energy as heat and ameliorate metabolic disorders, UCP1-expressing adipocytes are considered as a potential target for anti-obesity treatment. To monitor the expression of UCP1 in live mice in a non-invasive manner, we generated the Ucp1-iRFP720 knock-in (Ucp1-iRFP720 KI) mice, in which the gene encoding a near-infrared fluorescent protein iRFP720 is inserted into the Ucp1 gene locus. Using the heterozygous Ucp1-iRFP720 KI mice, we observed robust iRFP fluorescence in the interscapular region where brown adipose tissue is located. Moreover, the iRFP fluorescence was clearly observable in inguinal white adipose tissues in live mice administered with β3-adrenergic receptor agonist CL316,243. We also found that the homozygous Ucp1-iRFP720 KI mice, which are deficient in UCP1, displayed prominent iRFP fluorescence in the inguinal regions at the standard housing temperature. Consistent with this, the mice exhibited expanded populations of beige-like adipocytes in inguinal white adipose tissue, in which the Ucp1 promoter was dramatically activated. Thus, the Ucp1-iRFP720 KI mice provide a convenient model for non-invasive in vivo imaging of UCP1 expression in both brown and beige adipocytes in live mice.
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Affiliation(s)
- Aya Fukuda
- Laboratory of Gene Regulation, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Shiho Honda
- Laboratory of Gene Regulation, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Norie Fujioka
- Laboratory of Gene Regulation, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yuya Sekiguchi
- Laboratory of Gene Regulation, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Seiya Mizuno
- Laboratory of Animal Science, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yoshihiro Miwa
- Laboratory of Anatomy and Embryology, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Fumihiro Sugiyama
- Laboratory of Animal Science, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yohei Hayashi
- Laboratory of Gene Regulation, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Ken Nishimura
- Laboratory of Gene Regulation, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Koji Hisatake
- Laboratory of Gene Regulation, University of Tsukuba, Tsukuba, Ibaraki, Japan
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114
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Evans TD, Zhang X, Jeong SJ, He A, Song E, Bhattacharya S, Holloway KB, Lodhi IJ, Razani B. TFEB drives PGC-1α expression in adipocytes to protect against diet-induced metabolic dysfunction. Sci Signal 2019; 12:12/606/eaau2281. [PMID: 31690633 PMCID: PMC6882500 DOI: 10.1126/scisignal.aau2281] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
TFEB is a basic helix-loop-helix transcription factor that confers protection against metabolic diseases such as atherosclerosis by targeting a network of genes involved in autophagy-lysosomal biogenesis and lipid catabolism. In this study, we sought to characterize the role of TFEB in adipocyte and adipose tissue physiology and evaluate the therapeutic potential of adipocyte-specific TFEB overexpression in obesity. We demonstrated that mice with adipocyte-specific TFEB overexpression (Adipo-TFEB) were protected from diet-induced obesity, insulin resistance, and metabolic sequelae. Adipo-TFEB mice were lean primarily through increased metabolic rate, suggesting a role for adipose tissue browning and enhanced nonshivering thermogenesis in fat. Transcriptional characterization revealed that TFEB targeted genes involved in adipose tissue browning rather than those involved in autophagy. One such gene encoded PGC-1α, an established target of TFEB that promotes adipocyte browning. To dissect the role of PGC-1α in mediating the downstream effects of TFEB overexpression, we generated mice with adipocyte-specific PGC-1α deficiency and TFEB overexpression. Without PGC-1α, the ability of TFEB overexpression to brown adipose tissue and to elicit beneficial metabolic effects was blunted. Overall, these data implicate TFEB as a PGC-1α-dependent regulator of adipocyte browning and suggest its therapeutic potential in treating metabolic disease.
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Affiliation(s)
- Trent D Evans
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63112, USA
| | - Xiangyu Zhang
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63112, USA.,John Cochran VA Medical Center, St. Louis, MO 63106, USA
| | - Se-Jin Jeong
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63112, USA.,John Cochran VA Medical Center, St. Louis, MO 63106, USA
| | - Anyuan He
- Division of Endocrinology, Metabolism, and Lipid Research, Washington University School of Medicine, St. Louis, MO 63112, USA
| | - Eric Song
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63112, USA
| | - Somashubhra Bhattacharya
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63112, USA
| | - Karyn B Holloway
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63112, USA.,John Cochran VA Medical Center, St. Louis, MO 63106, USA
| | - Irfan J Lodhi
- Division of Endocrinology, Metabolism, and Lipid Research, Washington University School of Medicine, St. Louis, MO 63112, USA
| | - Babak Razani
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63112, USA. .,John Cochran VA Medical Center, St. Louis, MO 63106, USA.,Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63112, USA
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115
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Jia P, Wu X, Pan T, Xu S, Hu J, Ding X. Uncoupling protein 1 inhibits mitochondrial reactive oxygen species generation and alleviates acute kidney injury. EBioMedicine 2019; 49:331-340. [PMID: 31678001 PMCID: PMC6945195 DOI: 10.1016/j.ebiom.2019.10.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 10/05/2019] [Accepted: 10/14/2019] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Uncoupling protein 1 (UCP1) is predominantly found in brown adipose tissue mitochondria, and mediates energy dissipation to generate heat rather than ATP via functional mitochondrial uncoupling. However, little is known about its expression and function in kidney. METHODS We carried out a mRNA microarray analysis in mice kidneys with ischemia reperfusion (IR) injury. The most dramatically downregulated gene UCP1 after IR was identified, and its role in generation of mitochondrial reactive oxygen species (ROS) and oxidative stress injury was assessed both in vitro and in vivo. Genetic deletion of UCP1 was used to investigate the effects of UCP1 on ischemia or cisplatin-indued acute kidney injury (AKI) in mice. FINDINGS UCP1 was located in renal tubular epithelial cells in kidney and downregulated in a time-dependent manner during renal IR. Deletion of UCP1 increased oxidative stress in kidneys and aggravated ischemia or cisplatin induced AKI in mice.Viral-based overexpression of UCP1 reduced mitochondrial ROS generation and apoptosis in hypoxia-treated tubular epithelial cells. Furthermore, UCP1 expression was regulated by peroxisome proliferator-activator receptor (PPAR) γ in kidneys during renal IR. Overexpression of PPAR-γ resembled UCP1-overexpression phenotype in vitro. Treatment with PPAR-γ agonist could induce UCP1 upregulation and provide protective effect against renal IR injury in UCP1+/+mice, but not in UCP1-/-mice. INTERPRETATION UCP1 protects against AKI likely by suppressing oxidative stress, and activation of UCP1 represents a potential therapeutic strategy for AKI. FUND: National Natural Science Foundation of China grants, Science and Technology Commission of Shanghai.
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Affiliation(s)
- Ping Jia
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China; Kidney and Blood Purification Laboratory of Shanghai, Shanghai, China
| | - Xiaoli Wu
- Traditional Chinese Medicine Pharmacology Laboratory, Longhua Hospital, Shanghai University of Tranditional Chinese Medicine, Shanghai, China
| | - Tianyi Pan
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Sujuan Xu
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jiachang Hu
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xiaoqiang Ding
- Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China; Shanghai Medical Center of Kidney, Shanghai, China; Kidney and Dialysis Institute of Shanghai, Shanghai, China; Kidney and Blood Purification Laboratory of Shanghai, Shanghai, China; Hemodialysis quality control center of Shanghai, Shanghai, China.
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116
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Lizcano F. The Beige Adipocyte as a Therapy for Metabolic Diseases. Int J Mol Sci 2019; 20:ijms20205058. [PMID: 31614705 PMCID: PMC6834159 DOI: 10.3390/ijms20205058] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 09/30/2019] [Accepted: 10/05/2019] [Indexed: 12/16/2022] Open
Abstract
Adipose tissue is traditionally categorized into white and brown relating to their function and morphology. The classical white adipose tissue builds up energy in the form of triglycerides and is useful for preventing fatigue during periods of low caloric intake and the brown adipose tissue more energetically active, with a greater number of mitochondria and energy production in the form of heat. Since adult humans possess significant amounts of active brown fat depots and its mass inversely correlates with adiposity, brown fat might play an important role in human obesity and energy homeostasis. New evidence suggests two types of thermogenic adipocytes with distinct developmental and anatomical features: classical brown adipocytes and beige adipocytes. Beige adipocyte has recently attracted special interest because of its ability to dissipate energy and the possible ability to differentiate themselves from white adipocytes. The presence of brown and beige adipocyte in human adults has acquired attention as a possible therapeutic intervention for metabolic diseases. Importantly, adult human brown appears to be mainly composed of beige-like adipocytes, making this cell type an attractive therapeutic target for obesity and obesity-related diseases, such as atherosclerosis, arterial hypertension and diabetes mellitus type 2. Because many epigenetics changes can affect beige adipocyte differentiation from adipose progenitor cells, the knowledge of the circumstances that affect the development of beige adipocyte cells may be important to new pathways in the treatment of metabolic diseases. New molecules have emerged as possible therapeutic targets, which through the impulse to develop beige adipocytes can be useful for clinical studies. In this review will discuss some recent observations arising from the unique physiological capacity of these cells and their possible role as ways to treat obesity and diabetes mellitus type 2.
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Affiliation(s)
- Fernando Lizcano
- Center of Biomedical Investigation, (CIBUS), Universidad de La Sabana, 250008 Chia, Colombia.
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117
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Liu M, Zheng M, Cai D, Xie J, Jin Z, Liu H, Liu J. Zeaxanthin promotes mitochondrial biogenesis and adipocyte browning via AMPKα1 activation. Food Funct 2019; 10:2221-2233. [PMID: 30950462 DOI: 10.1039/c8fo02527d] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Zeaxanthin (ZEA), a type of oxygenated carotenoid with strong antioxidant activity, has previously been found to exhibit an anti-lipogenesis effect. In the present study, we investigated the effect of ZEA on brown-like adipocyte formation and mitochondrial biogenesis in 3T3-L1 adipocytes. Brown adipocyte-specific markers, mitochondrial biogenesis and oxidative stress, and the involvement of AMP-activated protein kinase (AMPK) α1 were assessed. ZEA treated adipocytes demonstrated a brown-like pattern, with upregulated expression of uncoupling protein 1 (UCP1) and other brown adipocyte markers. In addition, ZEA intervention induced a dramatic increase in mitochondrial DNA (mtDNA) content and in the mRNA levels of genes associated with mitochondrial biogenesis. Furthermore, ZEA attenuated mitochondrial oxidative damage caused by lipid peroxidation in adipocytes, significantly improved the mitochondrial membrane potential (MMP), and scavenged intracellular reactive oxygen species (ROS) and mitochondrial superoxide. Finally, we concluded that AMPKα1 mediated the ZEA-caused inhibition of lipid accumulation and promotion of brown and beige adipocyte-biomarker expression, as the positive effects of ZEA were diminished by Prkaa1 (AMPKα1) knockdown. These findings demonstrated that ZEA promoted the expression of brown and beige adipogenesis markers and mitochondrial biogenesis, which involved AMPKα1 activation, thus contributing to the anti-obesity effects of ZEA.
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Affiliation(s)
- Meihong Liu
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin 130118, China.
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118
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Rajagopal MC, Brown JW, Gelda D, Valavala KV, Wang H, Llano DA, Gillette R, Sinha S. Transient heat release during induced mitochondrial proton uncoupling. Commun Biol 2019; 2:279. [PMID: 31372518 PMCID: PMC6659641 DOI: 10.1038/s42003-019-0535-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 07/08/2019] [Indexed: 01/19/2023] Open
Abstract
Non-shivering thermogenesis through mitochondrial proton uncoupling is one of the dominant thermoregulatory mechanisms crucial for normal cellular functions. The metabolic pathway for intracellular temperature rise has widely been considered as steady-state substrate oxidation. Here, we show that a transient proton motive force (pmf) dissipation is more dominant than steady-state substrate oxidation in stimulated thermogenesis. Using transient intracellular thermometry during stimulated proton uncoupling in neurons of Aplysia californica, we observe temperature spikes of ~7.5 K that decay over two time scales: a rapid decay of ~4.8 K over ~1 s followed by a slower decay over ~17 s. The rapid decay correlates well in time with transient electrical heating from proton transport across the mitochondrial inner membrane. Beyond ~33 s, we do not observe any heating from intracellular sources, including substrate oxidation and pmf dissipation. Our measurements demonstrate the utility of transient thermometry in better understanding the thermochemistry of mitochondrial metabolism.
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Affiliation(s)
- Manjunath C. Rajagopal
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Jeffrey W. Brown
- College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Dhruv Gelda
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Krishna V. Valavala
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Huan Wang
- Re3 Innovative Neuroscience Institute, Sarasota, FL USA
| | - Daniel A. Llano
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Rhanor Gillette
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Sanjiv Sinha
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
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119
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Bertholet AM, Chouchani ET, Kazak L, Angelin A, Fedorenko A, Long JZ, Vidoni S, Garrity R, Cho J, Terada N, Wallace DC, Spiegelman BM, Kirichok Y. H + transport is an integral function of the mitochondrial ADP/ATP carrier. Nature 2019; 571:515-520. [PMID: 31341297 PMCID: PMC6662629 DOI: 10.1038/s41586-019-1400-3] [Citation(s) in RCA: 161] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 05/23/2019] [Indexed: 12/22/2022]
Abstract
The mitochondrial ADP/ATP carrier (AAC) is a major transport protein of the inner mitochondrial membrane. It exchanges mitochondrial ATP for cytosolic ADP and controls cellular production of ATP. In addition, it has been proposed that AAC mediates mitochondrial uncoupling, but it has proven difficult to demonstrate this function or to elucidate its mechanisms. Here we record AAC currents directly from inner mitochondrial membranes from various mouse tissues and identify two distinct transport modes: ADP/ATP exchange and H+ transport. The AAC-mediated H+ current requires free fatty acids and resembles the H+ leak via the thermogenic uncoupling protein 1 found in brown fat. The ADP/ATP exchange via AAC negatively regulates the H+ leak, but does not completely inhibit it. This suggests that the H+ leak and mitochondrial uncoupling could be dynamically controlled by cellular ATP demand and the rate of ADP/ATP exchange. By mediating two distinct transport modes, ADP/ATP exchange and H+ leak, AAC connects coupled (ATP production) and uncoupled (thermogenesis) energy conversion in mitochondria.
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Affiliation(s)
- Ambre M Bertholet
- Department of Physiology, University of California San Francisco, San Francisco, CA, USA
| | - Edward T Chouchani
- Dana-Farber Cancer Institute & Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Lawrence Kazak
- Dana-Farber Cancer Institute & Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Alessia Angelin
- Center for Mitochondrial and Epigenomic Medicine, Children's Hospital of Philadelphia, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Andriy Fedorenko
- Department of Physiology, University of California San Francisco, San Francisco, CA, USA
| | - Jonathan Z Long
- Dana-Farber Cancer Institute & Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Sara Vidoni
- Dana-Farber Cancer Institute & Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Ryan Garrity
- Dana-Farber Cancer Institute & Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Joonseok Cho
- Department of Pathology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Naohiro Terada
- Department of Pathology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Douglas C Wallace
- Center for Mitochondrial and Epigenomic Medicine, Children's Hospital of Philadelphia, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Bruce M Spiegelman
- Dana-Farber Cancer Institute & Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Yuriy Kirichok
- Department of Physiology, University of California San Francisco, San Francisco, CA, USA.
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120
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Jung SM, Sanchez-Gurmaches J, Guertin DA. Brown Adipose Tissue Development and Metabolism. Handb Exp Pharmacol 2019; 251:3-36. [PMID: 30203328 DOI: 10.1007/164_2018_168] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Brown adipose tissue is well known to be a thermoregulatory organ particularly important in small rodents and human infants, but it was only recently that its existence and significance to metabolic fitness in adult humans have been widely realized. The ability of active brown fat to expend high amounts of energy has raised interest in stimulating thermogenesis therapeutically to treat metabolic diseases related to obesity and type 2 diabetes. In parallel, there has been a surge of research aimed at understanding the biology of rodent and human brown fat development, its remarkable metabolic properties, and the phenomenon of white fat browning, in which white adipocytes can be converted into brown like adipocytes with similar thermogenic properties. Here, we review the current understanding of the developmental and metabolic pathways involved in forming thermogenic adipocytes, and highlight some of the many unknown functions of brown fat that make its study a rich and exciting area for future research.
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Affiliation(s)
- Su Myung Jung
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Joan Sanchez-Gurmaches
- Division of Endocrinology, Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, OH, USA. .,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
| | - David A Guertin
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA. .,Molecular, Cell and Cancer Biology Program, University of Massachusetts Medical School, Worcester, MA, USA. .,Lei Weibo Institute for Rare Diseases, University of Massachusetts Medical School, Worcester, MA, USA.
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121
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Abstract
Uncoupling protein 1 (UCP1) is an integral protein of the inner mitochondrial membrane (IMM) that is expressed specifically in brown and beige fat depots. UCP1 is responsible for the production of heat to control core body temperature, the regulation of fat metabolism, and the energy balance. As an uncoupling protein, UCP1 transports H+ across the IMM in presence of long-chain fatty acids (FA), which makes brown fat mitochondria produce heat at the expense of ATP. However, the exact mechanism of UCP1 action has remained difficult to elucidate, because direct methods for studying currents generated by UCP1 were unavailable. Recently, the patch-clamp technique was successfully applied to brown and beige fat mitochondria to directly study H+ currents across the IMM and characterize UCP1 function. A new model of the UCP1 mechanism was proposed based on the patch-clamp analysis. In this model, both FA anions (FA-) and H+ are transport substrates of UCP1, and UCP1 operates as a non-canonical FA-/H+ symporter. Here, we summarize recent findings obtained with the patch-clamp technique that describe how UCP1 can transport not only H+ but also FA-.
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122
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Dillon S, Staines KA, Millán JL, Farquharson C. How To Build a Bone: PHOSPHO1, Biomineralization, and Beyond. JBMR Plus 2019; 3:e10202. [PMID: 31372594 PMCID: PMC6659447 DOI: 10.1002/jbm4.10202] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 04/15/2019] [Accepted: 05/05/2019] [Indexed: 12/11/2022] Open
Abstract
Since its characterization two decades ago, the phosphatase PHOSPHO1 has been the subject of an increasing focus of research. This work has elucidated PHOSPHO1's central role in the biomineralization of bone and other hard tissues, but has also implicated the enzyme in other biological processes in health and disease. During mineralization PHOSPHO1 liberates inorganic phosphate (Pi) to be incorporated into the mineral phase through hydrolysis of its substrates phosphocholine (PCho) and phosphoethanolamine (PEA). Localization of PHOSPHO1 within matrix vesicles allows accumulation of Pi within a protected environment where mineral crystals may nucleate and subsequently invade the organic collagenous scaffold. Here, we examine the evidence for this process, first discussing the discovery and characterization of PHOSPHO1, before considering experimental evidence for its canonical role in matrix vesicle–mediated biomineralization. We also contemplate roles for PHOSPHO1 in disorders of dysregulated mineralization such as vascular calcification, along with emerging evidence of its activity in other systems including choline synthesis and homeostasis, and energy metabolism. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Scott Dillon
- The Roslin Institute and Royal (Dick) School of Veterinary Studies University of Edinburgh, Easter Bush Midlothian UK
| | | | - José Luis Millán
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla CA USA
| | - Colin Farquharson
- The Roslin Institute and Royal (Dick) School of Veterinary Studies University of Edinburgh, Easter Bush Midlothian UK
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123
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Adipocyte β-arrestin-2 is essential for maintaining whole body glucose and energy homeostasis. Nat Commun 2019; 10:2936. [PMID: 31270323 PMCID: PMC6610117 DOI: 10.1038/s41467-019-11003-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 06/12/2019] [Indexed: 02/05/2023] Open
Abstract
β-Arrestins are major regulators of G protein-coupled receptor-mediated signaling processes. Their potential roles in regulating adipocyte function in vivo remain unexplored. Here we report the novel finding that mice lacking β-arrestin-2 (barr2) selectively in adipocytes show significantly reduced adiposity and striking metabolic improvements when consuming excess calories. We demonstrate that these beneficial metabolic effects are due to enhanced signaling through adipocyte β3-adrenergic receptors (β3-ARs), indicating that barr2 represents a potent negative regulator of adipocyte β3-AR activity in vivo. Interestingly, essentially all beneficial metabolic effects caused by adipocyte barr2 deficiency are absent in adipocyte barr2-PRDM16 double KO mice, indicating that the metabolic improvements caused by the lack of barr2 in adipocytes are mediated by the browning/beiging of white adipose tissue. Our data support the novel concept that 'G protein-biased' β3-AR agonists that do not promote β3-AR/barr2 interactions may prove useful for the treatment of obesity and related metabolic disorders.
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124
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Qi G, Wang B, Zhang Y, Li H, Li C, Xu W, Jin Y. Living-Cell Imaging of Mitochondrial Membrane Potential Oscillation and Phenylalanine Metabolism Modulation during Periodic Electrostimulus. Anal Chem 2019; 91:9571-9579. [DOI: 10.1021/acs.analchem.9b00863] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Guohua Qi
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Bo Wang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, P. R. China
| | - Ying Zhang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, P. R. China
- University of Science and Technology of China, Hefei 230026, P. R. China
| | - Haijuan Li
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, P. R. China
| | - Chuanping Li
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Weiqing Xu
- State Key Laboratory of Supramolecular Structure and Materials, Jilin University, 2699 Qianjin Avenue, Changchun 130012, P. R. China
| | - Yongdong Jin
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- University of Science and Technology of China, Hefei 230026, P. R. China
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125
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Darcy J, Tseng YH. ComBATing aging-does increased brown adipose tissue activity confer longevity? GeroScience 2019; 41:285-296. [PMID: 31230192 DOI: 10.1007/s11357-019-00076-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 05/30/2019] [Indexed: 12/15/2022] Open
Abstract
Brown and its related beige adipose tissue (BAT) play a definitive role in maintaining body temperature by producing heat through uncoupling protein 1 (UCP1), which acts by dissociating oxidative phosphorylation from ATP production, resulting in the release of heat. Therefore, in order to maintain high thermogenic capacity, BAT must act as a metabolic sink by taking up vast amounts of circulating glucose and lipids for oxidation. This, along with the rediscovery of BAT in adult humans, has fueled the study of BAT as a putative therapeutic approach to manage the growing rates of obesity and metabolic syndromes. Notably, many of the beneficial consequences of BAT activity overlap with metabolic biomarkers of extended lifespan and healthspan. In this review, we provide background about BAT including the thermogenic program, BAT's role as a secretory organ, and differences between BAT in mice and humans. We also provide details on BAT during aging, and perspectives on the potential of targeting BAT to promote lifespan and healthspan.
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Affiliation(s)
- Justin Darcy
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, MA, 02215, USA
| | - Yu-Hua Tseng
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, MA, 02215, USA. .,Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.
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126
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Adaptive adipose tissue stromal plasticity in response to cold stress and antibody-based metabolic therapy. Sci Rep 2019; 9:8833. [PMID: 31222070 PMCID: PMC6586812 DOI: 10.1038/s41598-019-45354-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 05/29/2019] [Indexed: 01/09/2023] Open
Abstract
In response to environmental and nutrient stress, adipose tissues must establish a new homeostatic state. Here we show that cold exposure of obese mice triggers an adaptive tissue remodeling in visceral adipose tissue (VAT) that involves extracellular matrix deposition, angiogenesis, sympathetic innervation, and adipose tissue browning. Obese VAT is predominated by pro-inflammatory M1 macrophages; cold exposure induces an M1-to-M2 shift in macrophage composition and dramatic changes in macrophage gene expression in both M1 and M2 macrophages. Antibody-mediated CSF1R blocking prevented the cold-induced recruitment of adipose tissue M2 macrophages, suggesting the role of CSF1R signaling in the process. These cold-induced effects in obese VAT are phenocopied by an administration of the FGF21-mimetic antibody, consistent with its action to stimulate sympathetic nerves. Collectively, these studies illuminate adaptive visceral adipose tissue plasticity in obese mice in response to cold stress and antibody-based metabolic therapy.
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127
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Gamu D, Juracic ES, Hall KJ, Tupling AR. The sarcoplasmic reticulum and SERCA: a nexus for muscular adaptive thermogenesis. Appl Physiol Nutr Metab 2019; 45:1-10. [PMID: 31116956 DOI: 10.1139/apnm-2019-0067] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We are currently facing an "obesity epidemic" worldwide. Promoting inefficient metabolism in muscle represents a potential treatment for obesity and its complications. Sarco(endo)plasmic reticulum (SR) Ca2+-ATPase (SERCA) pumps in muscle are responsible for maintaining low cytosolic Ca2+ concentration through the ATP-dependent pumping of Ca2+ from the cytosol into the SR lumen. SERCA activity has the potential to be a critical regulator of body mass and adiposity given that it is estimated to contribute upwards of 20% of daily energy expenditure. More interestingly, this fraction can be modified physiologically in the face of stressors, such as ambient temperature and diet, through its physical interaction with several regulators known to inhibit Ca2+ uptake and muscle function. In this review, we discuss advances in our understanding of Ca2+-cycling thermogenesis within skeletal muscle, focusing on SERCA and its protein regulators, which were thought previously to only modulate muscular contractility. Novelty ATP consumption by SERCA pumps comprises a large proportion of resting energy expenditure in muscle and is dynamically regulated through interactions with small SERCA regulatory proteins. SERCA efficiency correlates significantly with resting metabolism, such that individuals with a higher resting metabolic rate have less energetically efficient SERCA Ca2+ pumping in muscle (i.e., lower coupling ratio). Futile Ca2+ cycling is a versatile heat generating mechanism utilized by both skeletal muscle and beige fat.
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Affiliation(s)
- Daniel Gamu
- Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.,Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Emma Sara Juracic
- Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.,Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Karlee J Hall
- Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.,Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - A Russell Tupling
- Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.,Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
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128
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Sun L, Lin JD. Function and Mechanism of Long Noncoding RNAs in Adipocyte Biology. Diabetes 2019; 68:887-896. [PMID: 31010880 PMCID: PMC6477904 DOI: 10.2337/dbi18-0009] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 02/19/2019] [Indexed: 12/17/2022]
Abstract
The last two decades have witnessed an explosion of interest in adipocyte biology, coinciding with the upsurge of obesity and metabolic syndrome. Now we have new perspectives on the distinct developmental origins of white, brown, and beige adipocytes and their role in metabolic physiology and disease. Beyond fuel metabolism, adipocytes communicate with the immune system and other tissues by releasing diverse paracrine and endocrine factors to orchestrate adipose tissue remodeling and maintain systemic homeostasis. Significant progress has been made in delineating the regulatory networks that govern different aspects of adipocyte biology. Here we provide an overview on the emerging role of long noncoding RNAs (lncRNAs) in the regulation of adipocyte development and metabolism and discuss the implications of the RNA-protein regulatory interface in metabolic control.
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Affiliation(s)
- Lei Sun
- Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore
| | - Jiandie D Lin
- Life Sciences Institute and Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, MI
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129
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Ježek P, Jabůrek M, Porter RK. Uncoupling mechanism and redox regulation of mitochondrial uncoupling protein 1 (UCP1). BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:259-269. [DOI: 10.1016/j.bbabio.2018.11.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 10/15/2018] [Accepted: 11/07/2018] [Indexed: 01/11/2023]
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130
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Cao Q, Jing J, Cui X, Shi H, Xue B. Sympathetic nerve innervation is required for beigeing in white fat. Physiol Rep 2019; 7:e14031. [PMID: 30873754 PMCID: PMC6418318 DOI: 10.14814/phy2.14031] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 11/24/2022] Open
Abstract
It is increasingly recognized that activation of beige adipocyte thermogenesis by pharmacological or genetic approaches increases energy expenditure and alleviates obesity. Sympathetic nervous system (SNS) directly innervating brown adipose tissue (BAT) and white adipose tissue (WAT) plays a key role in promoting nonshivering thermogenesis. However, direct evidence that supports the importance of SNS innervation for beige adipocyte formation is still lacking, and the significance of beige adipocyte thermogenesis in protection of body temperature during cold challenge is not clear. Here we tested the necessity of SNS innervation into WAT for beige adipocyte formation in mice with defective brown fat thermogenesis via interscapular BAT (iBAT) SNS denervation. SNS denervation was achieved by microinjection of 6-hydroxydopamine (6-OHDA), a selective neurotoxin to SNS nerves, into iBAT, inguinal WAT (iWAT), or both. The partial chemical denervation of iBAT SNS down-regulated UCP-1 protein expression in iBAT demonstrated by immunoblotting and immunohistochemical measurements. This was associated with an up-regulation of UCP1 protein expression and enhanced formation of beige cells in iWAT of mice with iBAT SNS denervation. In contrast, the chemical denervation of iWAT SNS completely abolished the upregulated UCP-1 protein and beige cell formation in iWAT of mice with iBAT SNS denervation. Our data demonstrate that SNS innervation in WAT is required for beige cell formation during cold-induced thermogenesis. We conclude that there exists a coordinated thermoregulation for BAT and WAT thermogenesis via a functional cross talk between BAT and WAT SNS.
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Affiliation(s)
- Qiang Cao
- School of BiologyGeorgia State UniversityAtlantaGeorgia
| | - Jia Jing
- School of BiologyGeorgia State UniversityAtlantaGeorgia
| | - Xin Cui
- School of BiologyGeorgia State UniversityAtlantaGeorgia
| | - Hang Shi
- School of BiologyGeorgia State UniversityAtlantaGeorgia
| | - Bingzhong Xue
- School of BiologyGeorgia State UniversityAtlantaGeorgia
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131
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Tanimura K, Suzuki T, Vargas D, Shibata H, Inagaki T. Epigenetic regulation of beige adipocyte fate by histone methylation. Endocr J 2019; 66:115-125. [PMID: 30606913 DOI: 10.1507/endocrj.ej18-0442] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Adipose tissue harbors plasticity to adapt to environmental thermal changes. While brown adipocyte is a thermogenic cell which produces heat acutely in response to cold stimuli, beige (or brite) adipocyte is an inducible form of thermogenic adipocytes which emerges in the white adipose depots in response to chronic cold exposure. Such adaptability of adipocytes is regulated by epigenetic mechanisms. Among them, histone methylation is chemically stable and thus is an appropriate epigenetic mark for mediating cellular memory to induce and maintain the beige adipocyte characteristics. The enzymes that catalyze the methylation or demethylation of H3K27 and H3K9 regulate brown adipocyte biogenesis through their catalytic activity-dependent and -independent mechanisms. Resolving the bivalency of H3K4me3 and H3K27me3 as well as "opening" the chromatin structure by demethylation of H3K9 both mediate beige adipogenesis. In addition, it is recently reported that maintenance of beige adipocyte, beige-to-white transition, and cellular memory of prior cold exposure in beige adipocyte are also regulated by histone methylation. A further understanding of the epigenetic mechanism of beige adipocyte biogenesis would unravel the mechanism of the cellular memory of environmental stimuli and provide a novel therapeutics for the metabolic disorders such as obesity and diabetes that are influenced by environmental factors.
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Affiliation(s)
- Kyoko Tanimura
- Laboratory of Epigenetics and Metabolism, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
- Department of Diabetes, Endocrinology, and Metabolism, Nippon Medical School, Tokyo 113-8603, Japan
| | - Tomohiro Suzuki
- Laboratory of Epigenetics and Metabolism, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
| | - Diana Vargas
- Laboratory of Epigenetics and Metabolism, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
| | - Hiroshi Shibata
- Laboratory of Epigenetics and Metabolism, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
| | - Takeshi Inagaki
- Laboratory of Epigenetics and Metabolism, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
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132
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Nishikawa S, Hyodo T, Nagao T, Nakanishi A, Tandia M, Tsuda T. α-Monoglucosyl Hesperidin but Not Hesperidin Induces Brown-Like Adipocyte Formation and Suppresses White Adipose Tissue Accumulation in Mice. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:1948-1954. [PMID: 30691268 DOI: 10.1021/acs.jafc.8b06647] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Hesperidin (HES) is a flavanone glycoside found in citrus peel that contributes to its bitter taste. It has low water solubility and poor oral bioavailability. To improve its solubility and bioavailability, α-monoglucosyl hesperidin (αGH) has been synthesized from HES by transglucosylation using cyclodextrin glucanotransferase. Several reports indicate that αGH significantly decreases body fat, but the underlying molecular mechanism remains unclear. We hypothesized that the antiobesity effects of αGH occur through the induced formation of brown-like adipocytes. The present study verified that dietary αGH induces brown-like adipocytes to form in mouse inguinal white adipose tissue (iWAT), thereby significantly decreasing the weight of white adipose tissue (WAT). Furthermore, dietary αGH significantly induced thermogenesis in iWAT. Dietary αGH also significantly suppressed high-fat-diet-induced WAT accumulation in mice, which may be mediated by brown-like adipocyte formation. These results indicate that dietary αGH induces increased energy expenditure by stimulating the formation of brown-like adipocytes.
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Affiliation(s)
- Sho Nishikawa
- College of Bioscience and Biotechnology , Chubu University , Matsumoto-cho, Kasugai , Aichi 487-8501 , Japan
| | - Takuma Hyodo
- College of Bioscience and Biotechnology , Chubu University , Matsumoto-cho, Kasugai , Aichi 487-8501 , Japan
| | - Tsubasa Nagao
- College of Bioscience and Biotechnology , Chubu University , Matsumoto-cho, Kasugai , Aichi 487-8501 , Japan
| | - Akihito Nakanishi
- Toyo Sugar Refining Company, Limited , Chuo-ku, Tokyo 103-0016 , Japan
| | - Mahamadou Tandia
- Toyo Sugar Refining Company, Limited , Chuo-ku, Tokyo 103-0016 , Japan
| | - Takanori Tsuda
- College of Bioscience and Biotechnology , Chubu University , Matsumoto-cho, Kasugai , Aichi 487-8501 , Japan
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133
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Chang SH, Song NJ, Choi JH, Yun UJ, Park KW. Mechanisms underlying UCP1 dependent and independent adipocyte thermogenesis. Obes Rev 2019; 20:241-251. [PMID: 30450758 DOI: 10.1111/obr.12796] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 09/16/2018] [Accepted: 09/30/2018] [Indexed: 12/29/2022]
Abstract
The growing focus on brown adipocytes has spurred an interest in their potential benefits for metabolic diseases. Brown and beige (or brite) adipocytes express high levels of uncoupling protein 1 (Ucp1) to dissipate heat instead of generating ATP. Ucp1 induction by stimuli including cold, exercise, and diet increases nonshivering thermogenesis, leading to increased energy expenditure and prevention of obesity. Recently, studies in adipocytes have indicated the existence of functional Ucp1-independent thermogenic regulators. Furthermore, substrate cycling involving creatine metabolites, cold-induced N-acyl amino acids, and oxidized lipids in white adipocytes can increase energy expenditure in the absence of Ucp1. These studies emphasize the need for a better understanding of the mechanisms governing energy expenditure in adipocytes and their potential applications in the prevention of human obesity and metabolic diseases.
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Affiliation(s)
- Seo-Hyuk Chang
- Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon, South Korea
| | - No-Joon Song
- Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon, South Korea
| | - Jin Hee Choi
- Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon, South Korea
| | - Ui Jeong Yun
- Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon, South Korea
| | - Kye Won Park
- Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon, South Korea
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134
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Sepa-Kishi DM, Jani S, Da Eira D, Ceddia RB. Cold acclimation enhances UCP1 content, lipolysis, and triacylglycerol resynthesis, but not mitochondrial uncoupling and fat oxidation, in rat white adipocytes. Am J Physiol Cell Physiol 2019; 316:C365-C376. [PMID: 30624981 DOI: 10.1152/ajpcell.00122.2018] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The objective of this study was to investigate whether cold-induced browning of the subcutaneous (Sc) inguinal (Ing) white adipose tissue (WAT) increases the capacity of this tissue to oxidize fatty acids through uncoupling protein 1 (UCP1)-mediated thermogenesis. To accomplish that, rats were acclimated to cold (4°C for 7 days). Subsequently, interscapular and aortic brown adipose tissues (iBAT and aBAT, respectively), epididymal (Epid), and Sc Ing WAT were used for adipocyte isolation. In BAT adipocytes, cold acclimation increased UCP1 content and palmitate oxidation either in the absence or presence of oligomycin, whereas in Sc Ing adipocytes glucose and palmitate oxidation were not affected, although multilocular adipocytes were formed and UCP1 content increased upon cold acclimation in the WAT. Furthermore, isoproterenol-stimulated cold Sc Ing adipocytes exhibited significantly lower rates of palmitate oxidation than control cells when exposed to oligomycin. These findings provide evidence that, despite increasing UCP1 levels, cold acclimation essentially reduced mitochondrial uncoupling-mediated fat oxidation in Sc Ing adipocytes. Conversely, glycerol kinase and phosphoenolpyruvate carboxykinase levels, isoproterenol-induced lipolysis, as well as glycerol and palmitate incorporation into lipids significantly increased in these cells. Therefore, instead of UCP1-mediated mitochondrial uncoupling, cold acclimation increased the capacity of Sc Ing adipocytes to export fatty acids and enhanced key components of the triacylglycerol resynthesis pathway in the Sc Ing WAT.
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Affiliation(s)
- Diane M Sepa-Kishi
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University , Toronto, Ontario , Canada
| | - Shailee Jani
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University , Toronto, Ontario , Canada
| | - Daniel Da Eira
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University , Toronto, Ontario , Canada
| | - Rolando B Ceddia
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University , Toronto, Ontario , Canada
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135
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Abstract
Brown and beige adipocytes can catabolize stored energy to generate heat, and this distinct capacity for thermogenesis could be leveraged as a therapy for metabolic diseases like obesity and type 2 diabetes. Thermogenic adipocytes drive heat production through close coordination of substrate supply with the mitochondrial oxidative machinery and effectors that control the rate of substrate oxidation. Together, this apparatus affords these adipocytes with tremendous capacity to drive thermogenesis. The best characterized thermogenic effector is uncoupling protein 1 (UCP1). Importantly, additional mechanisms for activating thermogenesis beyond UCP1 have been identified and characterized to varying extents. Acute regulation of these thermogenic pathways has been an active area of study, and numerous regulatory factors have been uncovered in recent years. Here we will review the evidence for regulators of heat production in thermogenic adipocytes in the context of the thermodynamic and kinetic principles that govern their therapeutic utility.
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Affiliation(s)
- Edward T Chouchani
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
| | - Lawrence Kazak
- Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada; Department of Biochemistry, McGill University, Montreal, QC, Canada.
| | - Bruce M Spiegelman
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
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136
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Darcy J, Bartke A. From White to Brown - Adipose Tissue Is Critical to the Extended Lifespan and Healthspan of Growth Hormone Mutant Mice. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1178:207-225. [PMID: 31493229 DOI: 10.1007/978-3-030-25650-0_11] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Growth hormone (GH) is a metabolic hormone that has major functions in the liver, muscle, and adipose tissue (AT). In the past 20 years, numerous studies have demonstrated that decreased growth hormone (GH) action is clearly linked to alterations in longevity. Therefore, it is not surprising that mechanisms underlying the extended longevity of GH-mutant animals include alterations in AT function. This Review aims to describe the basics of AT biology, GH secretion and action, and the effects of altered GH signaling in mice and humans. Lastly, this Review discusses the intersection of GH and AT, and how the influence of GH on AT may play a critical role in determining lifespan and healthspan.
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Affiliation(s)
- Justin Darcy
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA.
| | - Andrzej Bartke
- Department of Internal Medicine, Southern Illinois University School of Medicine, Springfield, IL, USA
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137
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Kazak L, Rahbani JF, Samborska B, Lu GZ, Jedrychowski MP, Lajoie M, Zhang S, Ramsay L, Dou FY, Tenen D, Chouchani ET, Dzeja P, Watson IR, Tsai L, Rosen ED, Spiegelman BM. Ablation of adipocyte creatine transport impairs thermogenesis and causes diet-induced obesity. Nat Metab 2019; 1:360-370. [PMID: 31161155 PMCID: PMC6544051 DOI: 10.1038/s42255-019-0035-x] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Lawrence Kazak
- Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada.
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada.
| | - Janane F Rahbani
- Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Bozena Samborska
- Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Gina Z Lu
- Dana-Farber Cancer Institute, Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Mark P Jedrychowski
- Dana-Farber Cancer Institute, Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Mathieu Lajoie
- Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Song Zhang
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
| | - LeeAnn Ramsay
- Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Florence Y Dou
- Dana-Farber Cancer Institute, Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Danielle Tenen
- Division of Endocrinology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Edward T Chouchani
- Dana-Farber Cancer Institute, Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Petras Dzeja
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
| | - Ian R Watson
- Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Linus Tsai
- Division of Endocrinology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Evan D Rosen
- Division of Endocrinology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Bruce M Spiegelman
- Dana-Farber Cancer Institute, Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
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138
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Madsen L, Myrmel LS, Fjære E, Øyen J, Kristiansen K. Dietary Proteins, Brown Fat, and Adiposity. Front Physiol 2018; 9:1792. [PMID: 30631281 PMCID: PMC6315128 DOI: 10.3389/fphys.2018.01792] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/28/2018] [Indexed: 12/15/2022] Open
Abstract
High protein diets have become popular for body weight maintenance and weight loss despite controversies regarding efficacy and safety. Although both weight gain and weight loss are determined by energy consumption and expenditure, data from rodent trials consistently demonstrate that the protein:carbohydrate ratio in high fat diets strongly influences body and fat mass gain per calorie eaten. Here, we review data from rodent trials examining how high protein diets may modulate energy metabolism and the mechanisms by which energy may be dissipated. We discuss the possible role of activating brown and so-called beige/BRITE adipocytes including non-canonical UCP1-independent thermogenesis and futile cycles, where two opposing metabolic pathways are operating simultaneously. We further review data on how the gut microbiota may affect energy expenditure. Results from human and rodent trials demonstrate that human trials are less consistent than rodent trials, where casein is used almost exclusively as the protein source. The lack of consistency in results from human trials may relate to the specific design of human trials, the possible distinct impact of different protein sources, and/or the differences in the efficiency of high protein diets to attenuate obesity development in lean subjects vs. promoting weight loss in obese subjects.
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Affiliation(s)
- Lise Madsen
- Institute of Marine Research, Bergen, Norway.,Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | | | - Even Fjære
- Institute of Marine Research, Bergen, Norway
| | | | - Karsten Kristiansen
- Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark
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139
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Schweizer S, Oeckl J, Klingenspor M, Fromme T. Substrate fluxes in brown adipocytes upon adrenergic stimulation and uncoupling protein 1 ablation. Life Sci Alliance 2018; 1:e201800136. [PMID: 30456392 PMCID: PMC6238590 DOI: 10.26508/lsa.201800136] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 11/05/2018] [Accepted: 11/05/2018] [Indexed: 12/22/2022] Open
Abstract
Brown adipocytes are highly specialized cells with the unique metabolic ability to dissipate chemical energy in the form of heat. We determined and inferred the flux of a number of key catabolic metabolites, their changes in response to adrenergic stimulation, and the dependency on the presence of the thermogenic uncoupling protein 1 and/or oxidative phosphorylation. This study provides reference values to approximate flux rates from a limited set of measured parameters in the future and thereby allows to evaluate the plausibility of claims about the capacity of metabolic adaptations or manipulations. From the resulting model, we delineate that in brown adipocytes (1) free fatty acids are a significant contributor to extracellular acidification, (2) glycogen is the dominant glycolytic substrate source in the acute response to an adrenergic stimulus, and (3) the futile cycling of free fatty acids between lipolysis and re-esterification into triglyceride provides a mechanism for uncoupling protein 1-independent, non-shivering thermogenesis in brown adipocytes.
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Affiliation(s)
- Sabine Schweizer
- Chair of Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Josef Oeckl
- Chair of Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.,EKFZ-Else Kröner-Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany.,ZIEL-Institute for Food and Health, Technical University of Munich, Freising, Germany
| | - Martin Klingenspor
- Chair of Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.,EKFZ-Else Kröner-Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany.,ZIEL-Institute for Food and Health, Technical University of Munich, Freising, Germany
| | - Tobias Fromme
- Chair of Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.,EKFZ-Else Kröner-Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany
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140
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LaMarche NM, Kohlgruber AC, Brenner MB. Innate T Cells Govern Adipose Tissue Biology. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 201:1827-1834. [PMID: 30224362 PMCID: PMC6201318 DOI: 10.4049/jimmunol.1800556] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/12/2018] [Indexed: 02/07/2023]
Abstract
During the past 25 y, the immune system has appeared as a key regulator of adipose tissue biology and metabolic homeostasis. In lean animals, adipose-resident leukocytes maintain an anti-inflammatory microenvironment that preserves the proper functioning of the tissue. In this review, we describe two populations of innate T cells enriched in adipose tissue, invariant NKT and γδ T cells, and how they serve overlapping and nonredundant roles in controlling adipose tissue functions. These cells interact with and expand anti-inflammatory regulatory T cells and M2 macrophages, thereby driving a metabolically beneficial tissue milieu. Surprisingly, we have found that adipose invariant NKT and γδ T cells also promote weight loss and heat production in a process called "nonshivering thermogenesis." The data surrounding these two cell types highlight their powerful ability to regulate not only other leukocytes, but also tissue-wide processes that affect an entire organism.
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Affiliation(s)
- Nelson M LaMarche
- Division of Rheumatology, Immunology, and Allergy, Harvard Medical School, Boston, MA 02115; and
| | - Ayano C Kohlgruber
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
| | - Michael B Brenner
- Division of Rheumatology, Immunology, and Allergy, Harvard Medical School, Boston, MA 02115; and
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141
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Huang J, Diaz-Meco MT, Moscat J. The macroenviromental control of cancer metabolism by p62. Cell Cycle 2018; 17:2110-2121. [PMID: 30198373 DOI: 10.1080/15384101.2018.1520566] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Metabolic reprogramming is a hallmark of cancer, but most studies focus on the molecular alterations in cancer cells and much less is known on the role of cancer metabolism, from a holistic perspective, for tumor initiation and progression. Increasing epidemiological evidence highlights the tremendous impact that cancer progression has on the host metabolism, especially in cachexia. However, how this benefits the tumor still is not completely understood. Here we review current studies on fatty acid oxidation in tumor cells as a potential therapeutic target in cancer, and how the redistribution of lipids from fat reservoirs to the cancer cell in the micro- and macro-environment impacts tumorigenesis by helping the tumor fulfill its energetic demands at the expense of fat. In this context, we also discuss the critical role of the signaling adaptor p62/Sequestosome 1(SQSTM1) in adipocytes in mediating tumor-induced fat reprograming and the feedback of adipose tissue on tumor aggressiveness via osteopontin and its potential implications in obesity-promoted cancer and fat cachexia. Collectively these studies highlight the importance of the symbiotic collaboration between adipose tissue and tumor to modulate the cancer metabolic fitness.
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Affiliation(s)
- Jianfeng Huang
- a Cancer Metabolism and Signaling Networks Program , Sanford Burnham Prebys Medical Discovery Institute , La Jolla , CA , USA
| | - Maria T Diaz-Meco
- a Cancer Metabolism and Signaling Networks Program , Sanford Burnham Prebys Medical Discovery Institute , La Jolla , CA , USA
| | - Jorge Moscat
- a Cancer Metabolism and Signaling Networks Program , Sanford Burnham Prebys Medical Discovery Institute , La Jolla , CA , USA
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142
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Santos RS, Frank AP, Fátima LA, Palmer BF, Öz OK, Clegg DJ. Activation of estrogen receptor alpha induces beiging of adipocytes. Mol Metab 2018; 18:51-59. [PMID: 30270132 PMCID: PMC6309577 DOI: 10.1016/j.molmet.2018.09.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 09/10/2018] [Accepted: 09/11/2018] [Indexed: 12/29/2022] Open
Abstract
Objectives Brown adipose tissue (BAT) and BAT-like adipose tissues, referred to as ‘beige’ adipose tissues uncouple respiration from ATP synthesis via uncoupling protein one (UCP-1). There is a sexual dimorphism with respect to beige and BAT tissues; pre-menopausal women have more BAT and are more sensitive to BAT activation than men or postmenopausal women. We hypothesized selective activation of adipose tissue estrogen receptor alpha (ERα) induces beiging of WAT through induction of lipolysis mediated by adipose tissue triglyceride lipase (ATGL). Methods 3T3-L1 and primary adipocytes were treated with the selective ERα agonist pyrazole triol (PPT), and selection deletion of ERα (using siRNA) was used to determine if selective ERα activation, or inhibition, influences the adipose tissue expression of genes associated with beiging. In a second series of experiments, ERα was selectively added back to adipose tissue of mice lacking total body ERα (ERKO) to determine if add back of ERα changed the morphology of adipose tissue to resemble beige tissues. Additionally, WT and ERKO mice were exposed to cold and FDG labeled glucose uptake was measured to determine the ability of cold to induce UCP-1 in ERKO mice. To begin to mechanistically probe how activation of ERα facilitates beiging, we tested the influence of PPT to activate the lipolytic pathway through ATGL. Finally, since ERα exerts its effects both at the genomic and non-genomic level depending on its cellular location, we determined in vivo if beiging occurs in mice expressing ERα only at the plasma membrane (MOER mice) or only at nucleus (NOER mice). Results Selective ERα activation by PPT increased markers of beiging in vitro in 3T3-L1 and primary adipocytes, whereas, knockdown of ERα with siRNA reduced the ability of PPT to induce beiging in vitro. ERα add back to the adipose tissue of ERKO mice resulted in multilocular adipose tissue resembling a beige phenotype. Following cold exposure, FDG labeled glucose in BAT tissues of ERKO mice was reduced when compared to weight-matched controls. Glycerol release and ATGL expression were increased after PPT treatment, while pre-treatment with the ATGL inhibitor prevented PPT's ability to increase UCP-1 expression. Finally, MOER mice were more sensitive to beiging of adipose tissues when compared to NOER mice. Conclusion Our results demonstrate for the first time that selective-activation of ERα in adipocytes increases markers of beiging and this is likely through induction of AMPK and ATGL-mediated lipolysis providing FFAs as a fuel to activate UCP-1. Selective activation of estrogen receptor alpha (ERα) increases markers of beiging in white adipocytes. Selective ERα activation increases glycerol release, lipolysis, markers of beiging of adipose tissues. Mice lacking ERα are cold intolerant demonstrating the necessity of ERα to facilitate brown adipose tissue activation. Mice with ERα only in the membrane (MOER mice) are more sensitive to a β3-adrenergic receptor induced beiging when compared to mice that express nuclear only ERα (NOER).
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Affiliation(s)
- Roberta S Santos
- Department of Biomedical Sciences, Diabetes & Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Aaron P Frank
- Department of Biomedical Sciences, Diabetes & Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Luciana A Fátima
- Department of Biomedical Sciences, Diabetes & Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Biff F Palmer
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Orhan K Öz
- Department of Radiology, Parkland Health and Hospital System, 5323 Harry Hines Blvd., Dallas, TX, 75390-8542, USA
| | - Deborah J Clegg
- Department of Biomedical Sciences, Diabetes & Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
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143
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Hankir MK, Klingenspor M. Brown adipocyte glucose metabolism: a heated subject. EMBO Rep 2018; 19:embr.201846404. [PMID: 30135070 DOI: 10.15252/embr.201846404] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 06/22/2018] [Accepted: 07/20/2018] [Indexed: 11/09/2022] Open
Abstract
The energy expending and glucose sink properties of brown adipose tissue (BAT) make it an attractive target for new obesity and diabetes treatments. Despite decades of research, only recently have mechanistic studies started to provide a more complete and consistent picture of how activated brown adipocytes handle glucose. Here, we discuss the importance of intracellular glycolysis, lactate production, lipogenesis, lipolysis, and beta-oxidation for BAT thermogenesis in response to natural (temperature) and artificial (pharmacological and optogenetic) forms of sympathetic nervous system stimulation. It is now clear that together, these metabolic processes in series and in parallel flexibly power ATP-dependent and independent futile cycles in brown adipocytes to impact on whole-body thermal, energy, and glucose balance.
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Affiliation(s)
- Mohammed K Hankir
- Department of Experimental Surgery, University Hospital Wuerzburg, Wuerzburg, Germany .,German Research Foundation Collaborative Research Center in Obesity Mechanisms 1052, University of Leipzig, Leipzig, Germany
| | - Martin Klingenspor
- Chair of Molecular Nutritional Medicine, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany .,EKFZ - Else Kröner-Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany
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144
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Abstract
Isoforms of creatine kinase (CK) generate and use phosphocreatine, a concentrated and highly diffusible cellular "high energy" intermediate, for the main purpose of energy buffering and transfer in order to maintain cellular energy homeostasis. The mitochondrial CK isoform (mtCK) localizes to the mitochondrial intermembrane and cristae space, where it assembles into peripherally membrane-bound, large cuboidal homooctamers. These are part of proteolipid complexes wherein mtCK directly interacts with cardiolipin and other anionic phospholipids, as well as with the VDAC channel in the outer membrane. This leads to a stabilization and cross-linking of inner and outer mitochondrial membrane, forming so-called contact sites. Also the adenine nucleotide translocator of the inner membrane can be recruited into these proteolipid complexes, probably mediated by cardiolipin. The complexes have functions mainly in energy transfer to the cytosol and stimulation of oxidative phosphorylation, but also in restraining formation of reactive oxygen species and apoptosis. In vitro evidence indicates a putative role of mtCK in mitochondrial phospholipid distribution, and most recently a role in thermogenesis has been proposed. This review summarizes the essential structural and functional data of these mtCK complexes and describes in more detail the more recent advances in phospholipid interaction, thermogenesis, cancer and evolution of mtCK.
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145
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Abstract
Obesity has become epidemic worldwide, which triggers several obesity-associated complications. Obesity is characterized by excess fat storage mainly in the visceral white adipose tissue (vWAT), subcutaneous WAT (sWAT), and other tissues. Myriad studies have demonstrated the crucial role of canonical Wnt/β-catenin cascade in the development of organs and physiological homeostasis, whereas recent studies show that genetic variations/mutations in the Wnt/β-catenin pathway are associated with human metabolic diseases. In this review, we highlight the regulation of updated Wnt/β-catenin signaling in obesity, especially the distinctly depot-specific roles between subcutaneous and visceral adipose tissue under high-fed diet stimulation and WAT browning process.
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Affiliation(s)
- Na Chen
- Department of Endocrinology and Metabolism, China National Research Center for Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jiqiu Wang
- Department of Endocrinology and Metabolism, China National Research Center for Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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146
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Stojanović O, Kieser S, Trajkovski M. Common traits between the beige fat-inducing stimuli. Curr Opin Cell Biol 2018; 55:67-73. [PMID: 30007128 DOI: 10.1016/j.ceb.2018.05.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 05/08/2018] [Accepted: 05/19/2018] [Indexed: 01/09/2023]
Abstract
Adipose tissues play an essential role in regulating the metabolic homeostasis and can be found in almost all parts of the body. Excessive adiposity leads to obesity and can contribute to metabolic and other disorders. Adipocytes show remarkable plasticity in their function, which can be pushed toward energy storage, or energy expenditure-a `browning' of fat. Browning is controlled by the cellular milieu of the adipose tissue, with sympathetic innervation and by immune responses as key integrators of the signals that promote browning. Here, we describe the latest contributions to our understanding of how different metabolic stimuli can shape the adipocyte function. We especially focus on the role of the gut microbiota and the negative energy balance in regulating the browning.
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Affiliation(s)
- Ozren Stojanović
- University of Geneva, Faculty of Medicine, Department of Cell Physiology and Metabolism, Centre Médical Universitaire, 1211 Geneva, Switzerland; University of Geneva, Diabetes Centre, Faculty of Medicine, 1211 Geneva, Switzerland
| | - Silas Kieser
- University of Geneva, Faculty of Medicine, Department of Cell Physiology and Metabolism, Centre Médical Universitaire, 1211 Geneva, Switzerland; University of Geneva, Diabetes Centre, Faculty of Medicine, 1211 Geneva, Switzerland
| | - Mirko Trajkovski
- University of Geneva, Faculty of Medicine, Department of Cell Physiology and Metabolism, Centre Médical Universitaire, 1211 Geneva, Switzerland; University of Geneva, Diabetes Centre, Faculty of Medicine, 1211 Geneva, Switzerland; Institute for Genetics and Genomics in Geneva, University of Geneva, 1211 Geneva, Switzerland.
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147
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Shao M, Gupta RK. Transcriptional brakes on the road to adipocyte thermogenesis. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:20-28. [PMID: 29800720 DOI: 10.1016/j.bbalip.2018.05.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 03/29/2018] [Accepted: 05/17/2018] [Indexed: 12/22/2022]
Abstract
White adipocytes represent the principle site for energy storage whereas brown/beige adipocytes emerge from seemingly distinct cellular lineages and burn chemical energy to produce heat. Thermogenic adipocytes utilize cell-type selective master regulatory transcription factors to drive the expression of their adipocyte thermogenic gene program. White adipocytes harbor transcriptional mechanisms to suppress the thermogenic gene program and maintain an energy-storing function. Here, we summarize some of the key developmental and transcriptional mechanisms leading to the postnatal recruitment of thermogenic adipocytes under physiological conditions, with a particular emphasis on the transcriptional "brakes" on the thermogenic gene program. We highlight a number of recent studies, including our own work on the transcription factor, ZFP423, that illustrate the potential to engineer the subcutaneous and visceral white fat lineages to adopt a thermogenic fat cell fate by releasing the inhibition of the adipocyte thermogenic gene program. These transcriptional brakes on adipocyte thermogenesis may represent potential targets of therapeutic interventions designed to combat obesity and associated metabolic disorders.
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Affiliation(s)
- Mengle Shao
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Rana K Gupta
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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148
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Emont MP, Kim DI, Wu J. Development, activation, and therapeutic potential of thermogenic adipocytes. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:13-19. [PMID: 29763732 DOI: 10.1016/j.bbalip.2018.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 02/23/2018] [Accepted: 05/10/2018] [Indexed: 01/28/2023]
Abstract
During the last decade, significant progress has been made in understanding adipocytes with a particular focus on thermogenic fat cells, which effectively convert chemical energy into heat in addition to their other metabolic functions. It has been increasingly recognized that different types and subtypes of adipocytes exist and the developmental origins of various types of fat cells are being intensively investigated. Previous work using immortalized fat cell lines has established an intricate transcriptional network that regulates adipocyte function. Recent work has illustrated how these key transcriptional components mediate thermogenic activation in fat cells. Last but not least, cumulative evidence supports an incontestable role of thermogenic fat in influencing systemic metabolism in humans. Here we summarize the exciting advancements in our understanding of thermogenic fat, discuss the advantages and limitations of the experimental tools currently available, and explore the future directions of this fast-evolving field.
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Affiliation(s)
- Margo P Emont
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Dong-Il Kim
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jun Wu
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
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149
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BonDurant LD, Potthoff MJ. Fibroblast Growth Factor 21: A Versatile Regulator of Metabolic Homeostasis. Annu Rev Nutr 2018; 38:173-196. [PMID: 29727594 DOI: 10.1146/annurev-nutr-071816-064800] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Fibroblast growth factor 21 (FGF21) is an endocrine hormone derived from the liver that exerts pleiotropic effects on the body to maintain overall metabolic homeostasis. During the past decade, there has been an enormous effort made to understand the physiological roles of FGF21 in regulating metabolism and to identify the mechanism for its potent pharmacological effects to reverse diabetes and obesity. Through both human and rodent studies, it is now evident that FGF21 levels are dynamically regulated by nutrient sensing, and consequently FGF21 functions as a critical regulator of nutrient homeostasis. In addition, recent studies using new genetic and molecular tools have provided critical insight into the actions of this endocrine factor. This review examines the numerous functions of FGF21 and highlights the therapeutic potential of FGF21-targeted pathways for treating metabolic disease.
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Affiliation(s)
- Lucas D BonDurant
- Department of Pharmacology and Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242, USA;
| | - Matthew J Potthoff
- Department of Pharmacology and Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242, USA;
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150
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Theoretical model and characteristics of mitochondrial thermogenesis. BIOPHYSICS REPORTS 2018; 4:63-67. [PMID: 29756006 PMCID: PMC5937889 DOI: 10.1007/s41048-018-0054-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 03/22/2018] [Indexed: 11/08/2022] Open
Abstract
Based on the first law of thermodynamics and the thermal diffusion equation, the deduced theoretical model of mitochondrial thermogenesis satisfies the Laplace equation and is a special case of the thermal diffusion equation. The model settles the long-standing question of the ability to increase cellular temperature by endogenous thermogenesis and explains the thermogenic characteristics of brown adipocytes. The model and calculations also suggest that the number of free available protons is the major limiting factor for endogenous thermogenesis and its speed.
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