1
|
Possa-Paranhos IC, Butts J, Pyszka E, Nelson C, Cho D, Sweeney P. Neuroanatomical dissection of the MC3R circuitry regulating energy rheostasis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.22.590573. [PMID: 38712101 PMCID: PMC11071362 DOI: 10.1101/2024.04.22.590573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Although mammals resist both acute weight loss and weight gain, the neural circuitry mediating bi-directional defense against weight change is incompletely understood. Global constitutive deletion of the melanocortin-3-receptor (MC3R) impairs the behavioral response to both anorexic and orexigenic stimuli, with MC3R knockout mice demonstrating increased weight gain following anabolic challenges and increased weight loss following anorexic challenges (i.e. impaired energy rheostasis). However, the brain regions mediating this phenotype remain incompletely understood. Here, we utilized MC3R floxed mice and viral injections of Cre-recombinase to selectively delete MC3R from medial hypothalamus (MH) in adult mice. Behavioral assays were performed on these animals to test the role of MC3R in MH in the acute response to orexigenic and anorexic challenges. Complementary chemogenetic approaches were used in MC3R-Cre mice to localize and characterize the specific medial hypothalamic brain regions mediating the role of MC3R in energy homeostasis. Finally, we performed RNAscope in situ hybridization to map changes in the mRNA expression of MC3R, POMC, and AgRP following energy rheostatic challenges. Our results demonstrate that MC3R deletion in MH increased feeding and weight gain following acute high fat diet feeding in males, and enhanced the anorexic effects of semaglutide, in a sexually dimorphic manner. Additionally, activation of DMH MC3R neurons increased energy expenditure and locomotion. Together, these results demonstrate that MC3R mediated effects on energy rheostasis result from the loss of MC3R signaling in the medial hypothalamus of adult animals and suggest an important role for DMH MC3R signaling in energy rheostasis. Key Points: MC3R signaling regulates energy rheostasis in adult miceMedial hypothalamus regulates energy rheostasis in adult miceEnergy rheostasis alters mRNA levels of AgRP and MC3R in DMHDMH MC3R neurons increase locomotion and energy expenditureMC3R expression in DMH is sexually dimorphic.
Collapse
|
2
|
Lund C, Ranea-Robles P, Falk S, Rausch DM, Skovbjerg G, Vibe-Petersen VK, Krauth N, Skytte JL, Vana V, Roostalu U, Pers TH, Lund J, Clemmensen C. Protection against overfeeding-induced weight gain is preserved in obesity but does not require FGF21 or MC4R. Nat Commun 2024; 15:1192. [PMID: 38331907 PMCID: PMC10853283 DOI: 10.1038/s41467-024-45223-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 01/18/2024] [Indexed: 02/10/2024] Open
Abstract
Overfeeding triggers homeostatic compensatory mechanisms that counteract weight gain. Here, we show that both lean and diet-induced obese (DIO) male mice exhibit a potent and prolonged inhibition of voluntary food intake following overfeeding-induced weight gain. We reveal that FGF21 is dispensable for this defense against weight gain. Targeted proteomics unveiled novel circulating factors linked to overfeeding, including the protease legumain (LGMN). Administration of recombinant LGMN lowers body weight and food intake in DIO mice. The protection against weight gain is also associated with reduced vascularization in the hypothalamus and sustained reductions in the expression of the orexigenic neuropeptide genes, Npy and Agrp, suggesting a role for hypothalamic signaling in this homeostatic recovery from overfeeding. Overfeeding of melanocortin 4 receptor (MC4R) KO mice shows that these mice can suppress voluntary food intake and counteract the enforced weight gain, although their rate of weight recovery is impaired. Collectively, these findings demonstrate that the defense against overfeeding-induced weight gain remains intact in obesity and involves mechanisms independent of both FGF21 and MC4R.
Collapse
Affiliation(s)
- Camilla Lund
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Pablo Ranea-Robles
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Sarah Falk
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Dylan M Rausch
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Grethe Skovbjerg
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
- Gubra ApS, Hørsholm, Denmark
| | | | - Nathalie Krauth
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | | | - Vasiliki Vana
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | | | - Tune H Pers
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Jens Lund
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Christoffer Clemmensen
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
3
|
Speakman JR, Hall KD. Models of body weight and fatness regulation. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220231. [PMID: 37661735 PMCID: PMC10475878 DOI: 10.1098/rstb.2022.0231] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/13/2023] [Indexed: 09/05/2023] Open
Abstract
Body weight and fatness appear to be regulated phenomena. Several different theoretical models are available to capture the essence of this idea. These include the set-point, dynamic equilibrium, adiposity force, control theory-settling point, Hall-Guo, operation point and dual intervention point (DIP) models. The set-point model posits a single reference point around which levels of fat are regulated. The dynamic equilibrium model suggests that the apparent regulation of body fat around a reference point is an illusion owing to the necessary impacts of weight change on energy expenditure. Control theory focuses on the importance of feedback gain and suggests set-point and dynamic equilibrium are ends of a continuum of feedback gain. Control theory models have also been called 'settling point' models. The Hall-Guo, operation point and DIP models also bring together the set-point and dynamic equilibrium ideas into a single framework. The DIP proposes a zone of indifference where dynamic equilibrium 'regulation' predominates, bounded by upper and lower intervention points beyond which physiological mechanisms are activated. The drifty gene hypothesis is an idea explaining where this individual variation in the upper intervention point might come from. We conclude that further experiments to test between the models are sorely required. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part II)'.
Collapse
Affiliation(s)
- John R. Speakman
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong Province, 518055, People's Republic of China
- School of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
- Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China
- China Medical University, Shenyang, Liaoning Province, 110122, People's Republic of China
| | - Kevin D. Hall
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
4
|
von Essen G, Lindsund E, Maldonado EM, Zouhar P, Cannon B, Nedergaard J. Highly recruited brown adipose tissue does not in itself protect against obesity. Mol Metab 2023; 76:101782. [PMID: 37499977 PMCID: PMC10432997 DOI: 10.1016/j.molmet.2023.101782] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 07/10/2023] [Accepted: 07/21/2023] [Indexed: 07/29/2023] Open
Abstract
OBJECTIVE The possibility to counteract the development of obesity in humans by recruiting brown or brite/beige adipose tissue (and thus UCP1) has attracted much attention. Here we examine if a diet that can activate diet-induced thermogenesis can exploit pre-enhanced amounts of UCP1 to counteract the development of diet-induced obesity. METHODS To investigate the anti-obesity significance of highly augmented amounts of UCP1 for control of body energy reserves, we physiologically increased total UCP1 amounts by recruitment of brown and brite/beige tissues in mice. We then examined the influence of the augmented UCP1 levels on metabolic parameters when the mice were exposed to a high-fat/high-sucrose diet under thermoneutral conditions. RESULTS The total UCP1 levels achieved were about 50-fold higher in recruited than in non-recruited mice. Contrary to underlying expectations, in the mice with highly recruited UCP1 and exposed to a high-fat/high-sucrose diet the thermogenic capacity of this UCP1 was completely inactivate. The mice even transiently (in an adipostat-like manner) demonstrated a higher metabolic efficiency and fat gain than did non-recruited mice. This was accomplished without altering energy expenditure or food absorption efficiency. The metabolic efficiency here was indistinguishable from that of mice totally devoid of UCP1. CONCLUSIONS Although UCP1 protein may be available, it is not inevitably utilized for diet-induced thermogenesis. Thus, although attempts to recruit UCP1 in humans may become successful as such, it is only if constant activation of the UCP1 is also achieved that amelioration of obesity development could be attained.
Collapse
Affiliation(s)
- Gabriella von Essen
- Department of Molecular Biosciences, The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Erik Lindsund
- Department of Molecular Biosciences, The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Elaina M Maldonado
- Department of Molecular Biosciences, The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Petr Zouhar
- Department of Molecular Biosciences, The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91 Stockholm, Sweden; Laboratory of Adipose Tissue Biology, Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, CZ-142 00 Prague, Czech Republic
| | - Barbara Cannon
- Department of Molecular Biosciences, The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Jan Nedergaard
- Department of Molecular Biosciences, The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91 Stockholm, Sweden.
| |
Collapse
|
5
|
Amin A, Badenes M, Tüshaus J, de Carvalho É, Burbridge E, Faísca P, Trávníčková K, Barros A, Carobbio S, Domingos PM, Vidal-Puig A, Moita LF, Maguire S, Stříšovský K, Ortega FJ, Fernández-Real JM, Lichtenthaler SF, Adrain C. Semaphorin 4B is an ADAM17-cleaved adipokine that inhibits adipocyte differentiation and thermogenesis. Mol Metab 2023; 73:101731. [PMID: 37121509 PMCID: PMC10197113 DOI: 10.1016/j.molmet.2023.101731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 04/20/2023] [Accepted: 04/21/2023] [Indexed: 05/02/2023] Open
Abstract
OBJECTIVE The metalloprotease ADAM17 (also called TACE) plays fundamental roles in homeostasis by shedding key signaling molecules from the cell surface. Although its importance for the immune system and epithelial tissues is well-documented, little is known about the role of ADAM17 in metabolic homeostasis. The purpose of this study was to determine the impact of ADAM17 expression, specifically in adipose tissues, on metabolic homeostasis. METHODS We used histopathology, molecular, proteomic, transcriptomic, in vivo integrative physiological and ex vivo biochemical approaches to determine the impact of adipose tissue-specific deletion of ADAM17 upon adipocyte and whole organism metabolic physiology. RESULTS ADAM17adipoq-creΔ/Δ mice exhibited a hypermetabolic phenotype characterized by elevated energy consumption and increased levels of adipocyte thermogenic gene expression. On a high fat diet, these mice were more thermogenic, while exhibiting elevated expression levels of genes associated with lipid oxidation and lipolysis. This hypermetabolic phenotype protected mutant mice from obesogenic challenge, limiting weight gain, hepatosteatosis and insulin resistance. Activation of beta-adrenoceptors by the neurotransmitter norepinephrine, a key regulator of adipocyte physiology, triggered the shedding of ADAM17 substrates, and regulated ADAM17 expression at the mRNA and protein levels, hence identifying a functional connection between thermogenic licensing and the regulation of ADAM17. Proteomic studies identified Semaphorin 4B (SEMA4B), as a novel ADAM17-shed adipokine, whose expression is regulated by physiological thermogenic cues, that acts to inhibit adipocyte differentiation and dampen thermogenic responses in adipocytes. Transcriptomic data showed that cleaved SEMA4B acts in an autocrine manner in brown adipocytes to repress the expression of genes involved in adipogenesis, thermogenesis, and lipid uptake, storage and catabolism. CONCLUSIONS Our findings identify a novel ADAM17-dependent axis, regulated by beta-adrenoceptors and mediated by the ADAM17-cleaved form of SEMA4B, that modulates energy balance in adipocytes by inhibiting adipocyte differentiation, thermogenesis and lipid catabolism.
Collapse
Affiliation(s)
- Abdulbasit Amin
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal; Department of Physiology, Faculty of Basic Medical Sciences, University of Ilorin, Nigeria
| | - Marina Badenes
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal; Faculty of Veterinary Medicine, Lusofona University, Lisbon, Portugal; Faculty of Veterinary Nursing, Polytechnic Institute of Lusofonia, Lisbon, Portugal
| | - Johanna Tüshaus
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany; Neuroproteomics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany
| | - Érika de Carvalho
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal; Instituto de Tecnologia Química da Universidade Nova de Lisboa (ITQB-Nova), Oeiras, Portugal
| | - Emma Burbridge
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal; Patrick G Johnston Centre for Cancer Research, Queen's University, Belfast, N. Ireland
| | - Pedro Faísca
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal
| | - Květa Trávníčková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - André Barros
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal
| | - Stefania Carobbio
- Centro de Investigacíon Principe Felipe (CIPF), Valencia, Spain; Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, UK
| | - Pedro M Domingos
- Instituto de Tecnologia Química da Universidade Nova de Lisboa (ITQB-Nova), Oeiras, Portugal
| | - Antonio Vidal-Puig
- Centro de Investigacíon Principe Felipe (CIPF), Valencia, Spain; Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, UK
| | - Luís F Moita
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal
| | - Sarah Maguire
- Patrick G Johnston Centre for Cancer Research, Queen's University, Belfast, N. Ireland
| | - Kvido Stříšovský
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Francisco J Ortega
- Girona Biomedical Research Institute (IDIBGI), Girona, Spain; Department of Medical Sciences, University of Girona, Girona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), and Institute of Salud Carlos III (ISCIII), Madrid, Spain
| | - José Manuel Fernández-Real
- Girona Biomedical Research Institute (IDIBGI), Girona, Spain; Department of Medical Sciences, University of Girona, Girona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), and Institute of Salud Carlos III (ISCIII), Madrid, Spain
| | - Stefan F Lichtenthaler
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany; Neuroproteomics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Colin Adrain
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal; Patrick G Johnston Centre for Cancer Research, Queen's University, Belfast, N. Ireland.
| |
Collapse
|
6
|
Abstract
BACKGROUND Body weight is defended by strong homeostatic forces. Several of the key biological mechanisms that counteract weight loss have been unraveled over the last decades. In contrast, the mechanisms that protect body weight and fat mass from becoming too high remain largely unknown. Understanding this aspect of energy balance regulation holds great promise for curbing the obesity epidemic. Decoding the physiological and molecular pathways that defend against weight gain can be achieved by an intervention referred to as 'experimental overfeeding'. SCOPE OF THE REVIEW In this review, we define experimental overfeeding and summarize the studies that have been conducted on animals. This field of research shows that experimental overfeeding induces a potent and prolonged hypophagic response that seems to be conserved across species and mediated by unidentified endocrine factors. In addition, the literature shows that experimental overfeeding can be used to model the development of non-alcoholic steatohepatitis and that forced intragastric infusion of surplus calories lowers survival from infections. Finally, we highlight studies indicating that experimental overfeeding can be employed to study the transgenerational effects of a positive energy balance and how dietary composition and macronutrient content might impact energy homeostasis and obesity development in animals. MAJOR CONCLUSIONS Experimental overfeeding of animals is a powerful yet underappreciated method to investigate the defense mechanisms against weight gain. This intervention also represents an alternative approach for studying the pathophysiology of metabolic liver diseases and the links between energy balance and infection biology. Future research in this field could help uncover why humans respond differently to an obesogenic environment and reveal novel pathways with therapeutic potential against obesity and cardiometabolic disorders.
Collapse
|
7
|
Guo J, Qian L, Ji J, Ji Z, Jiang Y, Wu Y, Yang Z, Ma G, Yao Y. Serpina3c regulates adipose differentiation via the Wnt/β-catenin-PPARγ pathway. Cell Signal 2022; 93:110299. [PMID: 35263629 DOI: 10.1016/j.cellsig.2022.110299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 02/22/2022] [Accepted: 03/01/2022] [Indexed: 12/15/2022]
Abstract
OBJECTIVE The Serpin protein family plays an important role in regulating the functioning of the adipose tissue. This study aimed to study the underlying mechanisms of Serpina3c in regulating adipogenesis. METHODS We developed a Serpina3c knockout (Serpina3c-/-) mouse model and Serpina3c knockdown and overexpression 3 T3-L1 preadipocyte models to evaluate the role of Serpina3c in adipose differentiation. Mice were fed on ND for 12-month or HFD for one month. The body weight, glucose tolerance, and insulin tolerance of the mice were subsequently measured. Lipid depositions and adipose tissue morphology were then detected using Oil red O staining and HE staining. qRT-PCR and Western blot were used to detect the expression of adipose differentiation transcription factors. RESULTS Serpina3c-/- mice exhibited lower body weight and white adipose tissue (WAT) weight than WT mice after 12 months of being fed on ND. Additionally, there was an increase in serum and hepatic triglyceride (TG) levels in Serpina3c-/- mice, without changes in glucose metabolism. Wnt/β-catenin was upregulated while PPARγ expression was decreased in knockout mice WAT. Impaired adipocyte differentiation caused by Serpina3c knockdown was reversed by IWR-1 and kallistatin through an increase in PPARγ expression. Serpina3c-/- mice fed on HFD for one month had a lower body weight and WAT than WT, accompanied by increased lipid depositions in the liver and muscles and severe insulin resistance. CONCLUSION Serpina3c promotes adipogenesis and maintains normal fat function by inhibiting the Wnt/β-catenin pathway.
Collapse
Affiliation(s)
- Jiaqi Guo
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China
| | - Linglin Qian
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China
| | - Jingjing Ji
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China
| | - Zhenjun Ji
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China
| | - Yu Jiang
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China
| | - Ya Wu
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China
| | - Ziwei Yang
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China
| | - Genshan Ma
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China
| | - Yuyu Yao
- Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing, Jiangsu 210009, China.
| |
Collapse
|
8
|
Çakır I, Hadley CK, Pan PL, Bagchi RA, Ghamari-Langroudi M, Porter DT, Wang Q, Litt MJ, Jana S, Hagen S, Lee P, White A, Lin JD, McKinsey TA, Cone RD. Histone deacetylase 6 inhibition restores leptin sensitivity and reduces obesity. Nat Metab 2022; 4:44-59. [PMID: 35039672 PMCID: PMC8892841 DOI: 10.1038/s42255-021-00515-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 12/07/2021] [Indexed: 01/05/2023]
Abstract
The adipose tissue-derived hormone leptin can drive decreases in food intake while increasing energy expenditure. In diet-induced obesity, circulating leptin levels rise proportionally to adiposity. Despite this hyperleptinemia, rodents and humans with obesity maintain increased adiposity and are resistant to leptin's actions. Here we show that inhibitors of the cytosolic enzyme histone deacetylase 6 (HDAC6) act as potent leptin sensitizers and anti-obesity agents in diet-induced obese mice. Specifically, HDAC6 inhibitors, such as tubastatin A, reduce food intake, fat mass, hepatic steatosis and improve systemic glucose homeostasis in an HDAC6-dependent manner. Mechanistically, peripheral, but not central, inhibition of HDAC6 confers central leptin sensitivity. Additionally, the anti-obesity effect of tubastatin A is attenuated in animals with a defective central leptin-melanocortin circuitry, including db/db and MC4R knockout mice. Our results suggest the existence of an HDAC6-regulated adipokine that serves as a leptin-sensitizing agent and reveals HDAC6 as a potential target for the treatment of obesity.
Collapse
Affiliation(s)
- Işın Çakır
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
| | - Colleen K Hadley
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- College of Literature, Science and the Arts, University of Michigan, Ann Arbor, MI, USA
| | - Pauline Lining Pan
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Pharmacology, University of Michigan Medical Center, Ann Arbor, MI, USA
| | - Rushita A Bagchi
- Department of Medicine, Division of Cardiology and the Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Masoud Ghamari-Langroudi
- Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN, USA
- Warren Center for Neuroscience Drug Discovery, Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | | | - Qiuyu Wang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Michael J Litt
- Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN, USA
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Somnath Jana
- Chemical Synthesis Core, Vanderbilt Institute of Chemical Biology, Nashville, TN, USA
| | - Susan Hagen
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Pil Lee
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Andrew White
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Jiandie D Lin
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Cell & Developmental Biology, Michigan Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Timothy A McKinsey
- Department of Medicine, Division of Cardiology and the Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Roger D Cone
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
- Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
9
|
Gallop MR, Wilson VC, Ferrante AW. Post-oral sensing of fat increases food intake and attenuates body weight defense. Cell Rep 2021; 37:109845. [PMID: 34686319 PMCID: PMC8609494 DOI: 10.1016/j.celrep.2021.109845] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/21/2021] [Accepted: 09/27/2021] [Indexed: 12/25/2022] Open
Abstract
In mammals, changes in weight elicit responses that favor a return to one's previous weight and promote weight stability. It has been hypothesized that palatable sweet and high-fat foods disturb the defense of body weight, leading to weight gain. We find that increasing sweetness or percent calories from fat increases diet palatability but that only increases in nutritive fat content increase caloric intake and body weight. In a mouse model of overfeeding that activates weight defense, high-fat diets, but not sweetened diets, attenuate the defense of body weight, leading to weight gain. The ability of a palatable, high-fat diet to increase food intake does not require tasting or smelling the food. Instead, the direct infusion of a high-fat diet into the stomach increases the ad libitum intake of less palatable, low-fat food. Post-oral sensing of percent calories from fat modulates feeding behavior to alter weight stability.
Collapse
Affiliation(s)
- Molly R Gallop
- Department of Medicine, Institute of Human Nutrition, Naomi Berrie Diabetes Center, Columbia University, New York, NY 10032, USA
| | - Victoria C Wilson
- Department of Medicine, Institute of Human Nutrition, Naomi Berrie Diabetes Center, Columbia University, New York, NY 10032, USA
| | - Anthony W Ferrante
- Department of Medicine, Institute of Human Nutrition, Naomi Berrie Diabetes Center, Columbia University, New York, NY 10032, USA.
| |
Collapse
|
10
|
Myers MG, Affinati AH, Richardson N, Schwartz MW. Central nervous system regulation of organismal energy and glucose homeostasis. Nat Metab 2021; 3:737-750. [PMID: 34158655 DOI: 10.1038/s42255-021-00408-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 05/12/2021] [Indexed: 02/05/2023]
Abstract
Growing evidence implicates the brain in the regulation of both immediate fuel availability (for example, circulating glucose) and long-term energy stores (that is, adipose tissue mass). Rather than viewing the adipose tissue and glucose control systems separately, we suggest that the brain systems that control them are components of a larger, highly integrated, 'fuel homeostasis' control system. This conceptual framework, along with new insights into the organization and function of distinct neuronal systems, provides a context within which to understand how metabolic homeostasis is achieved in both basal and postprandial states. We also review evidence that dysfunction of the central fuel homeostasis system contributes to the close association between obesity and type 2 diabetes, with the goal of identifying more effective treatment options for these common metabolic disorders.
Collapse
Affiliation(s)
- Martin G Myers
- Departments of Medicine and Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Alison H Affinati
- Departments of Medicine and Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Nicole Richardson
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Michael W Schwartz
- UW Medicine Diabetes Institute, Department of Medicine, University of Washington, Seattle, WA, USA.
| |
Collapse
|
11
|
Use of the ZDF rat to model dietary fat induced hypercoagulability is limited by progressive and fatal nephropathy. J Pharmacol Toxicol Methods 2020; 107:106933. [PMID: 33122074 DOI: 10.1016/j.vascn.2020.106933] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/31/2020] [Accepted: 10/06/2020] [Indexed: 01/22/2023]
Abstract
INTRODUCTION Zucker diabetic fatty (ZDF) rats are used widely as an animal model of metabolic syndrome and insulin resistance. Our study focused on the effects of high versus low dietary fat on the development of Type 2 diabetes in obese male ZDF rats (fa/fa), including biomarkers to detect early signs of hypercoagulability and vascular injury in the absence of overt thrombosis. METHODS In this study, male (5/group) 10-week-old CRL:ZDF370(obese) rats were fed low (LFD, 16.7% fat) or high fat (HFD, 60% fat) diet for 12 or 15 weeks. Cohorts of 5 rats within diet groups were scheduled for sample collection after weeks 12 and 15. RESULTS HFD-fed ZDF rats had oily coats, lower rates of food consumption, more accelerated weight gain and increased serum cholesterol (+15%) and triglyceride concentrations (+75%) vs. LFD-fed ZDF rats. Urinary ketones were observed only in HFD-fed ZDF rats and greater urine glucose and protein concentrations in HFD-fed ZDF vs. LFD-fed ZDF rats were seen. Hemostasis testing showed ~2-fold greater fibrinogen concentration, increased von Willebrand factor concentration, and high thrombin generation in HFD-fed ZDF vs LFD-fed ZDF rats. Increased mortality in the HFD-fed ZDF rat was attributed to exacerbations of altered carbohydrate metabolism as evidenced by ketonuria and nephropathy leading to renal failure. DISCUSSION This characterization shows that the ZDF rat at the age, sex and weight used in this study is highly sensitive to dietary fat content that can exacerbate prothrombotic, metabolic and renal disturbances and increase mortality.
Collapse
|
12
|
Münzberg H, Singh P, Heymsfield SB, Yu S, Morrison CD. Recent advances in understanding the role of leptin in energy homeostasis. F1000Res 2020; 9. [PMID: 32518627 PMCID: PMC7255681 DOI: 10.12688/f1000research.24260.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/19/2020] [Indexed: 01/04/2023] Open
Abstract
The hormone leptin plays a critical role in energy homeostasis, although our overall understanding of acutely changing leptin levels still needs improvement. Several developments allow a fresh look at recent and early data on leptin action. This review highlights select recent publications that are relevant for understanding the role played by dynamic changes in circulating leptin levels. We further discuss the relevance for our current understanding of leptin signaling in central neuronal feeding and energy expenditure circuits and highlight cohesive and discrepant findings that need to be addressed in future studies to understand how leptin couples with physiological adaptations of food intake and energy expenditure.
Collapse
Affiliation(s)
- Heike Münzberg
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| | - Prachi Singh
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| | - Steven B Heymsfield
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| | - Sangho Yu
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| | - Christopher D Morrison
- Pennington Biomedical Research Center, Louisiana State University System, Louisiana, USA
| |
Collapse
|
13
|
Berthoud HR, Morrison CD, Münzberg H. The obesity epidemic in the face of homeostatic body weight regulation: What went wrong and how can it be fixed? Physiol Behav 2020; 222:112959. [PMID: 32422162 DOI: 10.1016/j.physbeh.2020.112959] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 04/23/2020] [Accepted: 05/04/2020] [Indexed: 12/14/2022]
Abstract
Ever since the pioneering discoveries in the mid nineteen hundreds, the hypothalamus was recognized as a crucial component of the neural system controlling appetite and energy balance. The new wave of neuron-specific research tools has confirmed this key role of the hypothalamus and has delineated many other brain areas to be part of an expanded neural system sub serving these crucial functions. However, despite significant progress in defining this complex neural circuitry, many questions remain. One of the key questions is why the sophisticated body weight regulatory system is unable to prevent the rampant obesity epidemic we are experiencing. Why are pathologically obese body weight levels defended, and what can we do about it? Here we try to find answers to these questions by 1) reminding the reader that the neural controls of ingestive behavior have evolved in a demanding, restrictive environment and encompass much of the brain's major functions, far beyond the hypothalamus and brainstem, 2) hypothesizing that the current obesogenic environment impinges mainly on a critical pathway linking hypothalamic areas with the motivational and reward systems to produce uncompensated hyperphagia, and 3) proposing adequate strategies for prevention and treatment.
Collapse
Affiliation(s)
- Hans-Rudolf Berthoud
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA.
| | - Christopher D Morrison
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| | - Heike Münzberg
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| |
Collapse
|
14
|
Obesity and adiposity: the culprit of dietary protein efficacy. Clin Sci (Lond) 2020; 134:389-401. [DOI: 10.1042/cs20190583] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 01/24/2020] [Accepted: 02/10/2020] [Indexed: 12/14/2022]
Abstract
AbstractObesity and increased body adiposity have been alarmingly increasing over the past decades and have been linked to a rise in food intake. Many dietary restrictive approaches aiming at reducing weight have resulted in contradictory results. Additionally, some policies to reduce sugar or fat intake were not able to decrease the surge of obesity. This suggests that food intake is controlled by a physiological mechanism and that any behavioural change only leads to a short-term success. Several hypotheses have been postulated, and many of them have been rejected due to some limitations and exceptions. The present review aims at presenting a new theory behind the regulation of energy intake, therefore providing an eye-opening field for energy balance and a potential strategy for obesity management.
Collapse
|
15
|
Abstract
Human biology has evolved to keep body fat within a range that supports survival. During the last 25 years, obesity biologists have uncovered key aspects of physiology that prevent fat mass from becoming too low. In contrast, the mechanisms that counteract excessive adipose expansion are largely unknown. Evidence dating back to the 1950s suggests the existence of a blood-borne molecule that defends against weight gain. In this article, we discuss the research supporting an "unidentified factor of overfeeding" and models that explain its role in body weight control. If it exists, revealing the identity of this factor could end a long-lasting enigma of energy balance regulation and facilitate a much-needed breakthrough in the pharmacological treatment of obesity.
Collapse
Affiliation(s)
- Jens Lund
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Camilla Lund
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Morville
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Christoffer Clemmensen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
16
|
Sherman SB, Sarsour N, Salehi M, Schroering A, Mell B, Joe B, Hill JW. Prenatal androgen exposure causes hypertension and gut microbiota dysbiosis. Gut Microbes 2018; 9:400-421. [PMID: 29469650 PMCID: PMC6219642 DOI: 10.1080/19490976.2018.1441664] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Conditions of excess androgen in women, such as polycystic ovary syndrome (PCOS), often exhibit intergenerational transmission. One way in which the risk for PCOS may be increased in daughters of affected women is through exposure to elevated androgens in utero. Hyperandrogenemic conditions have serious health consequences, including increased risk for hypertension and cardiovascular disease. Recently, gut dysbiosis has been found to induce hypertension in rats, such that blood pressure can be normalized through fecal microbial transplant. Therefore, we hypothesized that the hypertension seen in PCOS has early origins in gut dysbiosis caused by in utero exposure to excess androgen. We investigated this hypothesis with a model of prenatal androgen (PNA) exposure and maternal hyperandrogenemia by single-injection of testosterone cypionate or sesame oil vehicle (VEH) to pregnant dams in late gestation. We then completed a gut microbiota and cardiometabolic profile of the adult female offspring. RESULTS The metabolic assessment revealed that adult PNA rats had increased body weight and increased mRNA expression of adipokines: adipocyte binding protein 2, adiponectin, and leptin in inguinal white adipose tissue. Radiotelemetry analysis revealed hypertension with decreased heart rate in PNA animals. The fecal microbiota profile of PNA animals contained higher relative abundance of bacteria associated with steroid hormone synthesis, Nocardiaceae and Clostridiaceae, and lower abundance of Akkermansia, Bacteroides, Lactobacillus, Clostridium. The PNA animals also had an increased relative abundance of bacteria associated with biosynthesis and elongation of unsaturated short chain fatty acids (SCFAs). CONCLUSIONS We found that prenatal exposure to excess androgen negatively impacted cardiovascular function by increasing systolic and diastolic blood pressure and decreasing heart rate. Prenatal androgen was also associated with gut microbial dysbiosis and altered abundance of bacteria involved in metabolite production of short chain fatty acids. These results suggest that early-life exposure to hyperandrogenemia in daughters of women with PCOS may lead to long-term alterations in gut microbiota and cardiometabolic function.
Collapse
Affiliation(s)
- Shermel B. Sherman
- Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH
| | - Nadeen Sarsour
- Department of Biological Sciences, University of Toledo, Toledo, OH
| | - Marziyeh Salehi
- Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH
| | - Allen Schroering
- Department of Neurosciences and Neurological Disorders, The University of Toledo College of Medicine and Life Sciences, Toledo, OH
| | - Blair Mell
- Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH,Center for Hypertension and Personalized Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH
| | - Bina Joe
- Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH,Center for Hypertension and Personalized Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH
| | - Jennifer W. Hill
- Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH,Center for Diabetes and Endocrine Research, The University of Toledo College of Medicine and Life Sciences, Toledo, OH,CONTACT Jennifer W. Hill, PhD Dept. of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Mail Stop 1008, 3000 Arlington Avenue, Toledo OH 43614
| |
Collapse
|
17
|
Perron IJ, Keenan BT, Chellappa K, Lahens NF, Yohn NL, Shockley KR, Pack AI, Veasey SC. Dietary challenges differentially affect activity and sleep/wake behavior in mus musculus: Isolating independent associations with diet/energy balance and body weight. PLoS One 2018; 13:e0196743. [PMID: 29746501 PMCID: PMC5945034 DOI: 10.1371/journal.pone.0196743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 04/18/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND AIMS Associated with numerous metabolic and behavioral abnormalities, obesity is classified by metrics reliant on body weight (such as body mass index). However, overnutrition is the common cause of obesity, and may independently contribute to these obesity-related abnormalities. Here, we use dietary challenges to parse apart the relative influence of diet and/or energy balance from body weight on various metabolic and behavioral outcomes. MATERIALS AND METHODS Seventy male mice (mus musculus) were subjected to the diet switch feeding paradigm, generating groups with various body weights and energetic imbalances. Spontaneous activity patterns, blood metabolite levels, and unbiased gene expression of the nutrient-sensing ventral hypothalamus (using RNA-sequencing) were measured, and these metrics were compared using standardized multivariate linear regression models. RESULTS Spontaneous activity patterns were negatively related to body weight (p<0.0001) but not diet/energy balance (p = 0.63). Both body weight and diet/energy balance predicted circulating glucose and insulin levels, while body weight alone predicted plasma leptin levels. Regarding gene expression within the ventral hypothalamus, only two genes responded to diet/energy balance (neuropeptide y [npy] and agouti-related peptide [agrp]), while others were related only to body weight. CONCLUSIONS Collectively, these results demonstrate that individual components of obesity-specifically obesogenic diets/energy imbalance and elevated body mass-can have independent effects on metabolic and behavioral outcomes. This work highlights the shortcomings of using body mass-based indices to assess metabolic health, and identifies novel associations between blood biomarkers, neural gene expression, and animal behavior following dietary challenges.
Collapse
Affiliation(s)
- Isaac J. Perron
- Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail: ,
| | - Brendan T. Keenan
- Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Karthikeyani Chellappa
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Nicholas F. Lahens
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Nicole L. Yohn
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Keith R. Shockley
- Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina, United States of America
| | - Allan I. Pack
- Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Sigrid C. Veasey
- Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| |
Collapse
|
18
|
Hao Z, Mumphrey MB, Morrison CD, Münzberg H, Ye J, Berthoud HR. Does gastric bypass surgery change body weight set point? INTERNATIONAL JOURNAL OF OBESITY SUPPLEMENTS 2016; 6:S37-S43. [PMID: 28685029 DOI: 10.1038/ijosup.2016.9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The relatively stable body weight during adulthood is attributed to a homeostatic regulatory mechanism residing in the brain which uses feedback from the body to control energy intake and expenditure. This mechanism guarantees that if perturbed up or down by design, body weight will return to pre-perturbation levels, defined as the defended level or set point. The fact that weight re-gain is common after dieting suggests that obese subjects defend a higher level of body weight. Thus, the set point for body weight is flexible and likely determined by the complex interaction of genetic, epigenetic and environmental factors. Unlike dieting, bariatric surgery does a much better job in producing sustained suppression of food intake and body weight, and an intensive search for the underlying mechanisms has started. Although one explanation for this lasting effect of particularly Roux-en-Y gastric bypass surgery (RYGB) is simple physical restriction due to the invasive surgery, a more exciting explanation is that the surgery physiologically reprograms the body weight defense mechanism. In this non-systematic review, we present behavioral evidence from our own and other studies that defended body weight is lowered after RYGB and sleeve gastrectomy. After these surgeries, rodents return to their preferred lower body weight if over- or underfed for a period of time, and the ability to drastically increase food intake during the anabolic phase strongly argues against the physical restriction hypothesis. However, the underlying mechanisms remain obscure. Although the mechanism involves central leptin and melanocortin signaling pathways, other peripheral signals such as gut hormones and their neural effector pathways likely contribute. Future research using both targeted and non-targeted 'omics' techniques in both humans and rodents as well as modern, genetically targeted, neuronal manipulation techniques in rodents will be necessary.
Collapse
Affiliation(s)
- Z Hao
- Neurobiology of Nutrition and Metabolism Department, Pennington Biomedical Research Center Louisiana State University System, Baton Rouge, LA, USA
| | - M B Mumphrey
- Neurobiology of Nutrition and Metabolism Department, Pennington Biomedical Research Center Louisiana State University System, Baton Rouge, LA, USA
| | - C D Morrison
- Neurobiology of Nutrition and Metabolism Department, Pennington Biomedical Research Center Louisiana State University System, Baton Rouge, LA, USA
| | - H Münzberg
- Neurobiology of Nutrition and Metabolism Department, Pennington Biomedical Research Center Louisiana State University System, Baton Rouge, LA, USA
| | - J Ye
- Neurobiology of Nutrition and Metabolism Department, Pennington Biomedical Research Center Louisiana State University System, Baton Rouge, LA, USA
| | - H R Berthoud
- Neurobiology of Nutrition and Metabolism Department, Pennington Biomedical Research Center Louisiana State University System, Baton Rouge, LA, USA
| |
Collapse
|
19
|
Carreiro AL, Dhillon J, Gordon S, Jacobs AG, Higgins KA, McArthur BM, Redan BW, Rivera RL, Schmidt LR, Mattes RD. The Macronutrients, Appetite, and Energy Intake. Annu Rev Nutr 2016; 36:73-103. [PMID: 27431364 PMCID: PMC4960974 DOI: 10.1146/annurev-nutr-121415-112624] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Each of the macronutrients-carbohydrate, protein, and fat-has a unique set of properties that influences health, but all are a source of energy. The optimal balance of their contribution to the diet has been a long-standing matter of debate. Over the past half century, thinking has progressed regarding the mechanisms by which each macronutrient may contribute to energy balance. At the beginning of this period, metabolic signals that initiated eating events (i.e., determined eating frequency) were emphasized. This was followed by an orientation to gut endocrine signals that purportedly modulate the size of eating events (i.e., determined portion size). Most recently, research attention has been directed to the brain, where the reward signals elicited by the macronutrients are viewed as potentially problematic (e.g., contribute to disordered eating). At this point, the predictive power of the macronutrients for energy intake remains limited.
Collapse
Affiliation(s)
- Alicia L Carreiro
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907
| | - Jaapna Dhillon
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907
| | - Susannah Gordon
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907
| | - Ashley G Jacobs
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907
| | - Kelly A Higgins
- Department of Food Science, Purdue University, West Lafayette, IN 47907
| | | | - Benjamin W Redan
- Department of Food Science, Purdue University, West Lafayette, IN 47907
| | - Rebecca L Rivera
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907
| | - Leigh R Schmidt
- Department of Food Science, Purdue University, West Lafayette, IN 47907
| | - Richard D Mattes
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907
| |
Collapse
|
20
|
McNamara JM, Houston AI, Higginson AD. Costs of Foraging Predispose Animals to Obesity-Related Mortality when Food Is Constantly Abundant. PLoS One 2015; 10:e0141811. [PMID: 26545121 PMCID: PMC4636368 DOI: 10.1371/journal.pone.0141811] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 10/13/2015] [Indexed: 01/30/2023] Open
Abstract
Obesity is an important medical problem affecting humans and animals in the developed world, but the evolutionary origins of the behaviours that cause obesity are poorly understood. The potential role of occasional gluts of food in determining fat-storage strategies for avoiding mortality have been overlooked, even though animals experienced such conditions in the recent evolutionary past and may follow the same strategies in the modern environment. Humans, domestic, and captive animals in the developed world are exposed to a surplus of calorie-rich food, conditions characterised as ‘constant-glut’. Here, we use a mathematical model to demonstrate that obesity-related mortality from poor health in a constant-glut environment should equal the average mortality rate in the ‘pre-modern’ environment when predation risk was more closely linked with foraging. It should therefore not be surprising that animals exposed to abundant food often over-eat to the point of ill-health. Our work suggests that individuals tend to defend a given excessive level of reserves because this level was adaptive when gluts were short-lived. The model predicts that mortality rate in constant-glut conditions can increase as the assumed health cost of being overweight decreases, meaning that any adaptation that reduced such health costs would have counter-intuitively led to an increase in mortality in the modern environment. Taken together, these results imply that efforts to reduce the incidence of obesity that are focussed on altering individual behaviour are likely to be ineffective because modern, constant-glut conditions trigger previously adaptive behavioural responses.
Collapse
Affiliation(s)
- John M. McNamara
- School of Mathematics, University of Bristol, University Walk, Bristol, BS8 1TW, United Kingdom
| | - Alasdair I. Houston
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, United Kingdom
| | - Andrew D. Higginson
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, United Kingdom
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QG, United Kingdom
- * E-mail:
| |
Collapse
|
21
|
Abstract
Mammals regulate fat mass so that increases or reductions in adipose tissue mass activate responses that favor return to one's previous weight. A reduction in fat mass activates a system that increases food intake and reduces energy expenditure; conversely, overfeeding and rapid adipose tissue expansion reduces food intake and increases energy expenditure. With the identification of leptin nearly two decades ago, the central circuit that defends against reductions in body fat was revealed. However, the systems that defend against rapid expansion of fat mass remain largely unknown. Here we review the physiology of the overfed state and evidence for a distinct regulatory system, which unlike the leptin-mediated system, we propose primarily measures a functional aspect of adipose tissue and not total mass per se.
Collapse
Affiliation(s)
- Yann Ravussin
- Department of Medicine, Columbia University, 1150 St. Nicholas Ave, New York, NY 10032, USA; Naomi Berrie Diabetes Center, Columbia University, 1150 St. Nicholas Ave, New York, NY 10032, USA
| | - Rudolph L Leibel
- Naomi Berrie Diabetes Center, Columbia University, 1150 St. Nicholas Ave, New York, NY 10032, USA; Department of Pediatrics, Columbia University, 1150 St. Nicholas Ave, New York, NY 10032, USA
| | - Anthony W Ferrante
- Department of Medicine, Columbia University, 1150 St. Nicholas Ave, New York, NY 10032, USA; Naomi Berrie Diabetes Center, Columbia University, 1150 St. Nicholas Ave, New York, NY 10032, USA.
| |
Collapse
|
22
|
Boomhower SR, Rasmussen EB, Doherty TS. Impulsive-choice patterns for food in genetically lean and obese Zucker rats. Behav Brain Res 2012; 241:214-21. [PMID: 23261877 DOI: 10.1016/j.bbr.2012.12.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 12/03/2012] [Accepted: 12/07/2012] [Indexed: 02/07/2023]
Abstract
Behavioral-economic studies have shown that differences between lean and obese Zuckers in food consumption depend on the response requirement for food. Since a response requirement inherently increases the delay to reinforcement, differences in sensitivity to delay may also be a relevant mechanism of food consumption in the obese Zucker rat. Furthermore, the endocannabinoid neurotransmitter system has been implicated in impulsivity, but studies that attempt to characterize the effects of cannabinoid drugs (e.g., rimonabant) on impulsive choice may be limited by floor effects. The present study aimed to characterize impulsive-choice patterns for sucrose using an adjusting-delay procedure in genetically lean and obese Zuckers. Ten lean and ten obese Zucker rats chose between one lever that resulted in one pellet after a standard delay (either 1 s or 5 s) and a second lever that resulted in two or three pellets after an adjusting delay. After behavior stabilized under baseline, rimonabant (0-10 mg/kg) was administered prior to some choice sessions in the two-pellet condition. Under baseline, obese Zuckers made more impulsive choices than leans in three of the four standard-delay/pellet conditions. Additionally, in the 2-pellet condition, rimonabant increased impulsive choice in lean rats in the 1-s standard-delay condition; however, rimonabant decreased impulsive choice in obese rats in the 1-s and 5-s standard-delay conditions. These data suggest that genetic factors that influence impulsive choice are stronger in some choice conditions than others, and that the endocannabinoid system may be a relevant neuromechanism.
Collapse
Affiliation(s)
- Steven R Boomhower
- Idaho State University, Department of Psychology, Mail Stop 8112, Pocatello, ID 83209-8112, United States
| | | | | |
Collapse
|
23
|
Guyenet SJ, Schwartz MW. Clinical review: Regulation of food intake, energy balance, and body fat mass: implications for the pathogenesis and treatment of obesity. J Clin Endocrinol Metab 2012; 97:745-55. [PMID: 22238401 PMCID: PMC3319208 DOI: 10.1210/jc.2011-2525] [Citation(s) in RCA: 179] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Accepted: 12/08/2011] [Indexed: 12/22/2022]
Abstract
CONTEXT Obesity has emerged as one of the leading medical challenges of the 21st century. The resistance of this disorder to effective, long-term treatment can be traced to the fact that body fat stores are subject to homeostatic regulation in obese individuals, just as in lean individuals. Because the growing obesity epidemic is linked to a substantial increase in daily energy intake, a key priority is to delineate how mechanisms governing food intake and body fat content are altered in an obesogenic environment. EVIDENCE ACQUISITION We considered all relevant published research and cited references that represented the highest quality evidence available. Where space permitted, primary references were cited. EVIDENCE SYNTHESIS The increase of energy intake that has fueled the U.S. obesity epidemic is linked to greater availability of highly rewarding/palatable and energy-dense food. Obesity occurs in genetically susceptible individuals and involves the biological defense of an elevated body fat mass, which may result in part from interactions between brain reward and homeostatic circuits. Inflammatory signaling, accumulation of lipid metabolites, or other mechanisms that impair hypothalamic neurons may also contribute to the development of obesity and offer a plausible mechanism to explain the biological defense of elevated body fat mass. CONCLUSIONS Despite steady research progress, mechanisms underlying the resistance to fat loss once obesity is established remain incompletely understood. Breakthroughs in this area may be required for the development of effective new obesity prevention and treatment strategies.
Collapse
Affiliation(s)
- Stephan J Guyenet
- Diabetes and Obesity Center of Excellence, Department of Medicine, University of Washington School of Medicine, South Lake Union, 815 Mercer Street, N334, Box 358055, Seattle, Washington 98109, USA
| | | |
Collapse
|
24
|
Purpera MN, Shen L, Taghavi M, Münzberg H, Martin RJ, Hutson SM, Morrison CD. Impaired branched chain amino acid metabolism alters feeding behavior and increases orexigenic neuropeptide expression in the hypothalamus. J Endocrinol 2012; 212:85-94. [PMID: 21969404 PMCID: PMC3350378 DOI: 10.1530/joe-11-0270] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [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
Elevation of dietary or brain leucine appears to suppress food intake via a mechanism involving mechanistic target of rapamycin, AMPK, and/or branched chain amino acid (BCAA) metabolism. Mice bearing a deletion of mitochondrial branched chain aminotransferase (BCATm), which is expressed in peripheral tissues (muscle) and brain glia, exhibit marked increases in circulating BCAAs. Here, we test whether this increase alters feeding behavior and brain neuropeptide expression. Circulating and brain levels of BCAAs were increased two- to four-fold in BCATm-deficient mice (KO). KO mice weighed less than controls (25·9 vs 20·4 g, P<0·01), but absolute food intake was relatively unchanged. In contrast to wild-type mice, KO mice preferred a low-BCAA diet to a control diet (P<0·05) but exhibited no change in preference for low- vs high-protein (HP) diets. KO mice also exhibited low leptin levels and increased hypothalamic Npy and Agrp mRNA. Normalization of circulating leptin levels had no effect on either food preference or the increased Npy and Agrp mRNA expression. If BCAAs act as signals of protein status, one would expect reduced food intake, avoidance of dietary protein, and reduction in neuropeptide expression in BCATm-KO mice. Instead, these mice exhibit an increased expression of orexigenic neuropeptides and an avoidance of BCAAs but not HP. These data thus suggest that either BCAAs do not act as physiological signals of protein status or the loss of BCAA metabolism within brain glia impairs the detection of protein balance.
Collapse
Affiliation(s)
| | - Li Shen
- Pennington Biomedical Research Center, Baton Rouge, La 70808
| | - Marzieh Taghavi
- Department of Human Nutrition, Foods & Exercise, Virginia Polytechnic Institute, Blacksburg, Virginia 24061
| | - Heike Münzberg
- Pennington Biomedical Research Center, Baton Rouge, La 70808
| | - Roy J. Martin
- Pennington Biomedical Research Center, Baton Rouge, La 70808
| | - Susan M. Hutson
- Department of Human Nutrition, Foods & Exercise, Virginia Polytechnic Institute, Blacksburg, Virginia 24061
| | - Christopher D. Morrison
- Pennington Biomedical Research Center, Baton Rouge, La 70808
- Corresponding Author and to whom reprint requests should be addressed: Christopher D. Morrison, Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, , 225-763-3145
| |
Collapse
|
25
|
Higuchi T, Mizuno A, Narita K, Ichimaru T, Murata T. Leptin resistance does not induce hyperphagia in the rat. J Physiol Sci 2012; 62:45-51. [PMID: 22144345 PMCID: PMC10717344 DOI: 10.1007/s12576-011-0184-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 11/17/2011] [Indexed: 10/15/2022]
Abstract
Leptin has been thought to work as a mediator for body weight control by inhibiting food intake. Leptin, however, cannot prevent obesity induced by a high-fat diet (HFD) probably because of leptin resistance. We investigated daily feeding and weight gain when ordinary chow (OC) was changed to a HFD in male rats. Food intake, by weight, significantly increased the next day, but gradually decreased until at 20 days the HFD intake contained the same calories as consumed by the OC-fed control rats. The reduction in food intake occurred only during the night without change of preference for the HFD, even after leptin resistance had developed. Nonetheless, the HFD-fed rats gained more weight than the controls. From the present experiment, it is concluded that leptin resistance does not induce hyperphagia, and suggested that body weight is not regulated to be constant.
Collapse
Affiliation(s)
- Takashi Higuchi
- Department of Integrative Physiology, University of Fukui, Matsuoka, Eiheiji-cho, Fukui, Japan.
| | | | | | | | | |
Collapse
|
26
|
Gloy VL, Lutz TA, Langhans W, Geary N, Hillebrand JJ. Basal plasma levels of insulin, leptin, ghrelin, and amylin do not signal adiposity in rats recovering from forced overweight. Endocrinology 2010; 151:4280-8. [PMID: 20668029 DOI: 10.1210/en.2010-0439] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This study examined how adiposity signals are related to adiposity during recovery from forced overweight (OW). Rats were rendered OW by chronic intragastric overfeeding (OW). Overfeeding was stopped when OW rats reached 126-129% of saline-infused normal-weight (NW) rats. Adipose tissue (AT) mass was estimated by computed tomography, and blood was drawn from chronic atrial cannulas throughout. Basal levels (i.e. after 2-3 h fasts late in the diurnal phase) of the hypothesized adiposity signals insulin, leptin, ghrelin, and amylin were assayed. OW rats gained approximately 130 g more body weight (BW) and approximately 100 g more AT mass during overfeeding. Plasma levels of insulin and leptin increased, whereas those of ghrelin decreased, linearly with AT mass; amylin did not change reliably. During recovery, OW rats' BW and AT mass decreased but were still elevated vs. NW rats after 39 d. OW rats' insulin returned to NW levels on d 1 of recovery and decreased below NW levels thereafter. Leptin was no longer elevated after d 8 of recovery. Ghrelin and amylin did not change reliably during recovery. Although AT mass decreased in OW rats during each intermeasurement interval between d 0 and d 23 of recovery, insulin and leptin did so during only the first interval (d 0-5). Insulin and leptin levels were exponentially related to AT mass during recovery. These data indicate that basal insulin, leptin, ghrelin, and amylin do not encode AT mass in rats dynamically regulating BW and adiposity during recovery from OW.
Collapse
Affiliation(s)
- Viktoria L Gloy
- Physiology and Behavior Laboratory, Institute of Food, Nutrition, and Health, ETH Zurich, Schorenstrasse 16, 8603 Schwerzenbach, Switzerland
| | | | | | | | | |
Collapse
|