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Vily-Petit J, Soty-Roca M, Silva M, Micoud M, Evrard F, Bron C, Raffin M, Beiroa D, Nogueiras R, Roussel D, Gautier-Stein A, Rajas F, Cota D, Mithieux G. Antiobesity effects of intestinal gluconeogenesis are mediated by the brown adipose tissue sympathetic nervous system. Obesity (Silver Spring) 2024; 32:710-722. [PMID: 38311801 DOI: 10.1002/oby.23985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 12/04/2023] [Accepted: 12/19/2023] [Indexed: 02/06/2024]
Abstract
OBJECTIVE Intestinal gluconeogenesis (IGN), via the initiation of a gut-brain nervous circuit, accounts for the metabolic benefits linked to dietary proteins or fermentable fiber in rodents and has been positively correlated with the rapid amelioration of body weight after gastric bypass surgery in humans with obesity. In particular, the activation of IGN moderates the development of hepatic steatosis accompanying obesity. In this study, we investigated the specific effects of IGN on adipose tissue metabolism, independent of its induction by nutritional manipulation. METHODS We used two transgenic mouse models of suppression or overexpression of G6pc1, the catalytic subunit of glucose-6 phosphatase, which is the key enzyme of endogenous glucose production specifically in the intestine. RESULTS Under a hypercaloric diet, mice overexpressing IGN showed lower adiposity and higher thermogenic capacities than wild-type mice, featuring marked browning of white adipose tissue (WAT) and prevention of the whitening of brown adipose tissue (BAT). Sympathetic denervation restricted to BAT caused the loss of the antiobesity effects associated with IGN. Conversely, IGN-deficient mice exhibited an increase in adiposity under a standard diet, which was associated with decreased expression of markers of thermogenesis in both BAT and WAT. CONCLUSIONS IGN is sufficient to activate the sympathetic nervous system and prevent the expansion and the metabolic alterations of BAT and WAT metabolism under a high-calorie diet, thereby preventing the development of obesity. These data increase knowledge of the mechanisms of weight reduction in gastric bypass surgery and pave the way for new approaches to prevent or cure obesity.
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Affiliation(s)
- Justine Vily-Petit
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Maud Soty-Roca
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Marine Silva
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Manon Micoud
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Félicie Evrard
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Clara Bron
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Margaux Raffin
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Daniel Beiroa
- Department of Physiology, School of Medicine, Singular Research Center in Molecular Medicine and Chronic Diseases, University of Santiago de Compostela-Health Research Institute Sanitaria, A Coruña, Spain
- CIBER Pathophysiology of Obesity and Nutrition (CIBERobn), Santiago de Compostela, Spain
| | - Rubén Nogueiras
- Department of Physiology, School of Medicine, Singular Research Center in Molecular Medicine and Chronic Diseases, University of Santiago de Compostela-Health Research Institute Sanitaria, A Coruña, Spain
- CIBER Pathophysiology of Obesity and Nutrition (CIBERobn), Santiago de Compostela, Spain
| | - Damien Roussel
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
- Scientific Research National Center, UMR 5023-LEHNA, Villeurbanne, France
| | - Amandine Gautier-Stein
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Fabienne Rajas
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
| | - Daniela Cota
- Bordeaux University, INSERM, Magendie Neurocenter, Bordeaux, France
| | - Gilles Mithieux
- Institute of Health and Medical Research, Lyon, France
- Claude Bernard Lyon University 1, Villeurbanne, France
- University of Lyon, Lyon, France
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2
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Heijkoop R, Lalanza JF, Solanas M, Álvarez-Monell A, Subias-Gusils A, Escorihuela RM, Snoeren EMS. Changes in reward-induced neural activity upon Cafeteria Diet consumption. Physiol Behav 2024; 276:114478. [PMID: 38307359 DOI: 10.1016/j.physbeh.2024.114478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/15/2024] [Accepted: 01/29/2024] [Indexed: 02/04/2024]
Abstract
Excessive consumption of highly palatable foods rich in sugar and fat, often referred to as "junk" or "fast" foods, plays a central role in the development of obesity. The highly palatable characteristics of these foods activate hedonic and motivational mechanisms to promote food-seeking behavior and overeating, which is largely regulated by the brain reward system. Excessive junk food consumption can alter the functioning of this reward system, but exact mechanisms of these changes are still largely unknown. This study investigated whether long-term junk food consumption, in the form of Cafeteria (CAF) diet, can alter the reward system in adult, female Long-Evans rats, and whether different regimes of CAF diet influence the extent of these changes. To this end, rats were exposed to a 6-week diet with either standard chow, or ad libitum daily access to CAF diet, 30 % restricted but daily access to CAF diet, or one-day-a-week (intermittent) ad libitum access to CAF diet, after which c-Fos expression in the Nucleus Accumbens (NAc), Prefrontal Cortex (PFC), and Ventral Tegmental Area (VTA) following consumption of a CAF reward of choice was examined. We found that all CAF diet regimes decreased c-Fos expression in the NAc-shell when presented with a CAF reward, while no changes in c-Fos expression upon the different diet regimes were found in the PFC, and possibly the VTA. Our data suggests that long-term junk food exposure can affect the brain reward system, resulting in an attenuated activity of the NAc-shell.
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Affiliation(s)
- R Heijkoop
- Department of Psychology, UiT The Arctic University of Norway, Norway
| | - J F Lalanza
- Department of Psychology, UiT The Arctic University of Norway, Norway
| | - M Solanas
- Institut de Neurociències, Universitat Autònoma de Barcelona, Spain; Medical Physiology Unit, Department of Cell Biology, Physiology and Immunology, Faculty of Medicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - A Álvarez-Monell
- Institut de Neurociències, Universitat Autònoma de Barcelona, Spain; Medical Physiology Unit, Department of Cell Biology, Physiology and Immunology, Faculty of Medicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - A Subias-Gusils
- Institut de Neurociències, Universitat Autònoma de Barcelona, Spain; Unitat de Psicologia Mèdica, Departament de Psiquiatria i Medicina Legal, Universitat Autònoma de Barcelona, Spain
| | - R M Escorihuela
- Institut de Neurociències, Universitat Autònoma de Barcelona, Spain; Unitat de Psicologia Mèdica, Departament de Psiquiatria i Medicina Legal, Universitat Autònoma de Barcelona, Spain
| | - E M S Snoeren
- Department of Psychology, UiT The Arctic University of Norway, Norway.
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3
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McDougle M, de Araujo A, Singh A, Yang M, Braga I, Paille V, Mendez-Hernandez R, Vergara M, Woodie LN, Gour A, Sharma A, Urs N, Warren B, de Lartigue G. Separate gut-brain circuits for fat and sugar reinforcement combine to promote overeating. Cell Metab 2024; 36:393-407.e7. [PMID: 38242133 DOI: 10.1016/j.cmet.2023.12.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 09/25/2023] [Accepted: 12/11/2023] [Indexed: 01/21/2024]
Abstract
Food is a powerful natural reinforcer that guides feeding decisions. The vagus nerve conveys internal sensory information from the gut to the brain about nutritional value; however, the cellular and molecular basis of macronutrient-specific reward circuits is poorly understood. Here, we monitor in vivo calcium dynamics to provide direct evidence of independent vagal sensing pathways for the detection of dietary fats and sugars. Using activity-dependent genetic capture of vagal neurons activated in response to gut infusions of nutrients, we demonstrate the existence of separate gut-brain circuits for fat and sugar sensing that are necessary and sufficient for nutrient-specific reinforcement. Even when controlling for calories, combined activation of fat and sugar circuits increases nigrostriatal dopamine release and overeating compared with fat or sugar alone. This work provides new insights into the complex sensory circuitry that mediates motivated behavior and suggests that a subconscious internal drive to consume obesogenic diets (e.g., those high in both fat and sugar) may impede conscious dieting efforts.
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Affiliation(s)
- Molly McDougle
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA; Center for Integrative Cardiovascular and Metabolic Disease, University of Florida, Gainesville, FL, USA; Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Alan de Araujo
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA; Center for Integrative Cardiovascular and Metabolic Disease, University of Florida, Gainesville, FL, USA
| | - Arashdeep Singh
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA; Center for Integrative Cardiovascular and Metabolic Disease, University of Florida, Gainesville, FL, USA; Monell Chemical Senses Center, Philadelphia, PA, USA; Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Mingxin Yang
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA; Center for Integrative Cardiovascular and Metabolic Disease, University of Florida, Gainesville, FL, USA; Monell Chemical Senses Center, Philadelphia, PA, USA; Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Isadora Braga
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA; Monell Chemical Senses Center, Philadelphia, PA, USA; Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Vincent Paille
- Monell Chemical Senses Center, Philadelphia, PA, USA; Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA; UMR1280 Physiopathologie des adaptations nutritionnelles, INRAE, Institut des maladies de l'appareil digestif, Université de Nantes, Nantes, France
| | - Rebeca Mendez-Hernandez
- Monell Chemical Senses Center, Philadelphia, PA, USA; Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Macarena Vergara
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA; Center for Integrative Cardiovascular and Metabolic Disease, University of Florida, Gainesville, FL, USA
| | - Lauren N Woodie
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania, Philadelphia, PA, USA
| | - Abhishek Gour
- Department of Pharmaceutics, University of Florida, Gainesville, FL, USA
| | - Abhisheak Sharma
- Department of Pharmaceutics, University of Florida, Gainesville, FL, USA
| | - Nikhil Urs
- Department of Pharmacology, University of Florida, Gainesville, FL, USA
| | - Brandon Warren
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA
| | - Guillaume de Lartigue
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA; Center for Integrative Cardiovascular and Metabolic Disease, University of Florida, Gainesville, FL, USA; Monell Chemical Senses Center, Philadelphia, PA, USA; Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA.
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Gautier-Stein A, Vily-Petit J, Rajas F, Mithieux G. Intestinal gluconeogenesis: A translator of nutritional information needed for glycemic and emotional balance. Biochimie 2023:S0300-9084(23)00313-9. [PMID: 38040189 DOI: 10.1016/j.biochi.2023.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 11/17/2023] [Accepted: 11/23/2023] [Indexed: 12/03/2023]
Abstract
At the interface between the outside world and the self, the intestine is the first organ receiving nutritional information. One intestinal function, gluconeogenesis, is activated by various nutrients, particularly diets enriched in fiber or protein, and thus results in glucose production in the portal vein in the post-absorptive period. The detection of portal glucose induces a nervous signal controlling the activity of the central nuclei involved in the regulation of metabolism and emotional behavior. Induction of intestinal gluconeogenesis is necessary for the beneficial effects of fiber or protein-enriched diets on metabolism and emotional behavior. Through its ability to translate nutritional information from the diet to the brain's regulatory centers, intestinal gluconeogenesis plays an essential role in maintaining physiological balance.
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Affiliation(s)
- Amandine Gautier-Stein
- Universite Claude Bernard Lyon 1, NUDICE, UMR_S 1213, Villeurbanne, 69100, France; Institut National de la Sante et de la Recherche Medicale, NUDICE, UMR_S 1213, Lyon, 69372, France.
| | - Justine Vily-Petit
- Universite Claude Bernard Lyon 1, NUDICE, UMR_S 1213, Villeurbanne, 69100, France; Institut National de la Sante et de la Recherche Medicale, NUDICE, UMR_S 1213, Lyon, 69372, France
| | - Fabienne Rajas
- Universite Claude Bernard Lyon 1, NUDICE, UMR_S 1213, Villeurbanne, 69100, France; Institut National de la Sante et de la Recherche Medicale, NUDICE, UMR_S 1213, Lyon, 69372, France
| | - Gilles Mithieux
- Universite Claude Bernard Lyon 1, NUDICE, UMR_S 1213, Villeurbanne, 69100, France; Institut National de la Sante et de la Recherche Medicale, NUDICE, UMR_S 1213, Lyon, 69372, France
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5
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Vily-Petit J, Soty M, Silva M, Micoud M, Bron C, Guérin-Deremaux L, Mithieux G. Improvement of energy metabolism associated with NUTRIOSE® soluble fiber, a dietary ingredient exhibiting prebiotic properties, requires intestinal gluconeogenesis. Food Res Int 2023; 167:112723. [PMID: 37087279 DOI: 10.1016/j.foodres.2023.112723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 01/16/2023] [Accepted: 01/21/2023] [Indexed: 03/29/2023]
Abstract
While the prevalence of obesity progresses worldwide, the consumption of sugars and dietary fiber increases and decreases, respectively. In this context, NUTRIOSE® soluble fiber is a plant-based food ingredient with beneficial effects in Humans. Here, we studied in mice the mechanisms involved, particularly the involvement of intestinal gluconeogenesis (IGN), the essential function in the beneficial effects of dietary fibers. To determine whether NUTRIOSE® exerts its beneficial effects via the activation of IGN, we studied the effects of dietary NUTRIOSE® on the development of obesity, diabetes and non-alcoholic fatty liver disease (NAFLD), which IGN is able to prevent. To assert the role of IGN in the observed effects, we studied wild-type (WT) and IGN-deficient mice. In line with our hypothesis, NUTRIOSE® exerts metabolic benefits in WT mice, but not in IGN-deficient mice. Indeed, WT mice are protected from body weight gain and NAFLD induced by a high calorie diet. In addition, our data suggests that NUTRIOSE® may improve energy balance by activating a browning process in subcutaneous white adipose tissue. While the gut microbiota composition changes with NUTRIOSE®, this is not sufficient in itself to account for the benefits observed. On the contrary, IGN is obligatory in the NUTRIOSE® benefits, since no benefit take place in absence of IGN. In conclusion, IGN plays a crucial and essential role in the set-up of the beneficial effects of NUTRIOSE®, highlighting the interest of the supplementation of food with healthy ingredients in the context of the current obesity epidemic.
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Affiliation(s)
- Justine Vily-Petit
- Institut de la Santé et de la Recherche Médicale, U1213 Lyon, France; Université Claude Bernard Lyon1, Villeurbanne, France; Université de Lyon, Lyon, France
| | - Maud Soty
- Institut de la Santé et de la Recherche Médicale, U1213 Lyon, France; Université Claude Bernard Lyon1, Villeurbanne, France; Université de Lyon, Lyon, France
| | - Marine Silva
- Institut de la Santé et de la Recherche Médicale, U1213 Lyon, France; Université Claude Bernard Lyon1, Villeurbanne, France; Université de Lyon, Lyon, France
| | - Manon Micoud
- Institut de la Santé et de la Recherche Médicale, U1213 Lyon, France; Université Claude Bernard Lyon1, Villeurbanne, France; Université de Lyon, Lyon, France
| | - Clara Bron
- Institut de la Santé et de la Recherche Médicale, U1213 Lyon, France; Université Claude Bernard Lyon1, Villeurbanne, France; Université de Lyon, Lyon, France
| | | | - Gilles Mithieux
- Institut de la Santé et de la Recherche Médicale, U1213 Lyon, France; Université Claude Bernard Lyon1, Villeurbanne, France; Université de Lyon, Lyon, France.
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6
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Intestinal gluconeogenesis: metabolic benefits make sense in the light of evolution. Nat Rev Gastroenterol Hepatol 2023; 20:183-194. [PMID: 36470967 DOI: 10.1038/s41575-022-00707-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/27/2022] [Indexed: 03/02/2023]
Abstract
The intestine, like the liver and kidney, in various vertebrates and humans is able to carry out gluconeogenesis and release glucose into the blood. In the fed post-absorptive state, intestinal glucose is sensed by the gastrointestinal nervous system. The latter initiates a signal to the brain regions controlling energy homeostasis and stress-related behaviour. Intestinal gluconeogenesis (IGN) is activated by several complementary mechanisms, in particular nutritional situations (for example, when food is enriched in protein or fermentable fibre and after gastric bypass surgery in obesity). In these situations, IGN has several metabolic and behavioural benefits. As IGN is activated by nutrients capable of fuelling systemic gluconeogenesis, IGN could be a signal to the brain that food previously ingested is suitable for maintaining plasma glucose for a while. This process might account for the benefits observed. Finally, in this Perspective, we discuss how the benefits of IGN in fasting and fed states could explain why IGN emerged and was maintained in vertebrates by natural selection.
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7
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Pittaras E, Hamelin H, Granon S. Inter-Individual Differences in Cognitive Tasks: Focusing on the Shaping of Decision-Making Strategies. Front Behav Neurosci 2022; 16:818746. [PMID: 35431831 PMCID: PMC9007591 DOI: 10.3389/fnbeh.2022.818746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/24/2022] [Indexed: 11/13/2022] Open
Abstract
In this paper, we review recent (published and novel) data showing inter-individual variation in decision-making strategies established by mice in a gambling task (MGT for Mouse Gambling Task). It may look intriguing, at first, that congenic animals develop divergent behaviors. However, using large groups of mice, we show that individualities emerge in the MGT, with about 30% of healthy mice displaying risk-averse choices while about 20-25% of mice make risk-prone choices. These strategies are accompanied by different brain network mobilization and individual levels of regional -prefrontal and striatal- monoamines. We further illustrate three ecological ways that influence drastically cognitive strategies in healthy adult mice: sleep deprivation, sucrose or artificial sweetener exposure, and regular exposure to stimulating environments. Questioning how to unmask individual strategies, what are their neural/neurochemical bases and whether we can shape or reshape them with different environmental manipulations is of great value, first to understand how the brain may build flexible decisions, and second to study behavioral plasticity, in healthy adult, as well as in developing brains. The latter may open new avenues for the identification of vulnerability traits to adverse events, before the emergence of mental pathologies.
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Affiliation(s)
- Elsa Pittaras
- Heller Laboratory, Department of Biology, Stanford University, Stanford, CA, United States
| | - Héloïse Hamelin
- Institut des Neurosciences Paris-Saclay, CNRS UMR 9197, Saclay, France
| | - Sylvie Granon
- Institut des Neurosciences Paris-Saclay, CNRS UMR 9197, Saclay, France
- *Correspondence: Sylvie Granon,
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Meng Q, Culnan DM, Ahmed T, Sun M, Cooney RN. Roux-en-Y gastric bypass alters intestinal glucose transport in the obese Zucker rat. Front Endocrinol (Lausanne) 2022; 13:901984. [PMID: 36034439 PMCID: PMC9405183 DOI: 10.3389/fendo.2022.901984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 07/18/2022] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION The gastrointestinal tract plays a major role in regulating glucose homeostasis and gut endocrine function. The current study examines the effects of Roux-en-Y gastric bypass (RYGB) on intestinal GLP-1, glucose transporter expression and function in the obese Zucker rat (ZR). METHODS Two groups of ZRs were studied: RYGB and sham surgery pair-fed (PF) fed rats. Body weight and food intake were measured daily. On post-operative day (POD) 21, an oral glucose test (OGT) was performed, basal and 30-minute plasma, portal venous glucose and glucagon-like peptide-1 (GLP-1) levels were measured. In separate ZRs, the biliopancreatic, Roux limb (Roux) and common channel (CC) intestinal segments were harvested on POD 21. RESULTS Body weight was decreased in the RYGB group. Basal and 30-minute OGT plasma and portal glucose levels were decreased after RYGB. Basal plasma GLP-1 levels were similar, while a 4.5-fold increase in GLP-1 level was observed in 30-minute after RYGB (vs. PF). The increase in basal and 30-minute portal venous GLP-1 levels after RYGB were accompanied by increased mRNA expressions of proglucagon and PC 1/3, GPR119 protein in the Roux and CC segments. mRNA and protein levels of FFAR2/3 were increased in Roux segment. RYGB decreased brush border glucose transport, transporter proteins (SGLT1 and GLUT2) and mRNA levels of Tas1R1/Tas1R3 and α-gustducin in the Roux and CC segments. CONCLUSIONS Reductions in intestinal glucose transport and enhanced post-prandial GLP-1 release were associated with increases in GRP119 and FFAR2/3 after RYGB in the ZR model. Post-RYGB reductions in the regulation of intestinal glucose transport and L cell receptors regulating GLP-1 secretion represent potential mechanisms for improved glycemic control.
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Affiliation(s)
- Qinghe Meng
- Department of Surgery, State University of New York (SUNY), Upstate Medical University, Syracuse, NY, United States
| | - Derek M. Culnan
- Burn and Reconstructive Centers of America, Jackson, MS, United States
| | - Tamer Ahmed
- Department of Surgery, State University of New York (SUNY), Upstate Medical University, Syracuse, NY, United States
| | - Mingjie Sun
- Department of Surgery, Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Robert N. Cooney
- Department of Surgery, State University of New York (SUNY), Upstate Medical University, Syracuse, NY, United States
- *Correspondence: Robert N. Cooney,
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Hamelin H, Poizat G, Florian C, Kursa MB, Pittaras E, Callebert J, Rampon C, Taouis M, Hamed A, Granon S. Prolonged Consumption of Sweetened Beverages Lastingly Deteriorates Cognitive Functions and Reward Processing in Mice. Cereb Cortex 2021; 32:1365-1378. [PMID: 34491298 DOI: 10.1093/cercor/bhab274] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 07/10/2021] [Accepted: 07/12/2021] [Indexed: 12/25/2022] Open
Abstract
We investigated the detrimental effects of chronic consumption of sweet or sweetened beverages in mice. We report that consumption of beverages containing small amounts of sucrose during several weeks impaired reward systems. This is evidenced by robust changes in the activation pattern of prefrontal brain regions associated with abnormal risk-taking and delayed establishment of decision-making strategy. Supporting these findings, we find that chronic consumption of low doses of artificial sweeteners such as saccharin disrupts brain regions' activity engaged in decision-making and reward processes. Consequently, this leads to the rapid development of inflexible decisions, particularly in a subset of vulnerable individuals. Our data also reveal that regular consumption, even at low doses, of sweet or sweeteners dramatically alters brain neurochemistry, i.e., dopamine content and turnover, and high cognitive functions, while sparing metabolic regulations. Our findings suggest that it would be relevant to focus on long-term consequences on the brain of sweet or sweetened beverages in humans, especially as they may go metabolically unnoticed.
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Affiliation(s)
- Héloïse Hamelin
- Université Paris-Saclay, CNRS, Institut des Neurosciences Paris-Saclay, 91190, Gif-ur-Yvette, France
| | - Ghislaine Poizat
- Université Paris-Saclay, CNRS, Institut des Neurosciences Paris-Saclay, 91190, Gif-ur-Yvette, France
| | - Cédrick Florian
- Research Center on Animal Cognition (CRCA), Center for Integrative Biology, CNRS UMR 5169, Toulouse 31062, France
| | - Miron Bartosz Kursa
- Interdisciplinary Centre for Mathematical and Computational Modelling, University of Warsaw, 02-106 Warsaw, Poland
| | - Elsa Pittaras
- Stanford University, Heller Laboratory, Stanford, CA 94305-5020, USA
| | - Jacques Callebert
- Service of Biochemistry and Molecular Biology, INSERM U942, Hospital Lariboisière, APHP, Paris 75010, France
| | - Claire Rampon
- Research Center on Animal Cognition (CRCA), Center for Integrative Biology, CNRS UMR 5169, Toulouse 31062, France
| | - Mohammed Taouis
- Université Paris-Saclay, CNRS, Institut des Neurosciences Paris-Saclay, 91190, Gif-ur-Yvette, France
| | - Adam Hamed
- Laboratory of Spatial Memory, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland
| | - Sylvie Granon
- Université Paris-Saclay, CNRS, Institut des Neurosciences Paris-Saclay, 91190, Gif-ur-Yvette, France
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Guzmán-Ruiz MA, Jiménez A, Cárdenas-Rivera A, Guerrero-Vargas NN, Organista-Juárez D, Guevara-Guzmán R. Regulation of Metabolic Health by an "Olfactory-Hypothalamic Axis" and Its Possible Implications for the Development of Therapeutic Approaches for Obesity and T2D. Cell Mol Neurobiol 2021; 42:1727-1743. [PMID: 33813677 DOI: 10.1007/s10571-021-01080-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 03/12/2021] [Indexed: 12/12/2022]
Abstract
The olfactory system is responsible for the reception, integration and interpretation of odors. However, in the last years, it has been discovered that the olfactory perception of food can rapidly modulate the activity of hypothalamic neurons involved in the regulation of energy balance. Conversely, the hormonal signals derived from changes in the metabolic status of the body can also change the sensitivity of the olfactory system, suggesting that the bidirectional relationship established between the olfactory and the hypothalamic systems is key for the maintenance of metabolic homeostasis. In the first part of this review, we describe the possible mechanisms and anatomical pathways involved in the modulation of energy balance regulated by the olfactory system. Hence, we propose a model to explain its implication in the maintenance of the metabolic homeostasis of the organism. In the second part, we discuss how the olfactory system could be involved in the development of metabolic diseases such as obesity and type two diabetes and, finally, we propose the use of intranasal therapies aimed to regulate and improve the activity of the olfactory system that in turn will be able to control the neuronal activity of hypothalamic centers to prevent or ameliorate metabolic diseases.
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Affiliation(s)
- Mara Alaide Guzmán-Ruiz
- Laboratorio Sensorial, Departamento de Fisiología, Facultad de Medicina, Edificio A, 4º piso, Universidad Nacional Autónoma de México (UNAM), 04510, Ciudad de México, México.
| | - Adriana Jiménez
- Laboratorio Sensorial, Departamento de Fisiología, Facultad de Medicina, Edificio A, 4º piso, Universidad Nacional Autónoma de México (UNAM), 04510, Ciudad de México, México
| | - Alfredo Cárdenas-Rivera
- Centro de Investigación en Bioingeniería, Universidad de Ingeniería y Tecnología, Lima, Perú
| | - Natalí N Guerrero-Vargas
- Departamento de Anatomía, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, México
| | - Diana Organista-Juárez
- Laboratorio Sensorial, Departamento de Fisiología, Facultad de Medicina, Edificio A, 4º piso, Universidad Nacional Autónoma de México (UNAM), 04510, Ciudad de México, México
| | - Rosalinda Guevara-Guzmán
- Laboratorio Sensorial, Departamento de Fisiología, Facultad de Medicina, Edificio A, 4º piso, Universidad Nacional Autónoma de México (UNAM), 04510, Ciudad de México, México.
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11
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Hypothalamic detection of macronutrients via multiple gut-brain pathways. Cell Metab 2021; 33:676-687.e5. [PMID: 33450178 PMCID: PMC7933100 DOI: 10.1016/j.cmet.2020.12.018] [Citation(s) in RCA: 84] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 10/30/2020] [Accepted: 12/23/2020] [Indexed: 12/24/2022]
Abstract
Food intake is tightly regulated by complex and coordinated gut-brain interactions. Nutrients rapidly modulate activity in key populations of hypothalamic neurons that regulate food intake, including hunger-sensitive agouti-related protein (AgRP)-expressing neurons. Because individual macronutrients engage specific receptors in the gut to communicate with the brain, we reasoned that macronutrients may utilize different pathways to reduce activity in AgRP neurons. Here, we revealed that AgRP neuron activity in hungry mice is inhibited by site-specific intestinal detection of different macronutrients. We showed that vagal gut-brain signaling is required for AgRP neuron inhibition by fat. In contrast, spinal gut-brain signaling relays the presence of intestinal glucose. Further, we identified glucose sensors in the intestine and hepatic portal vein that mediate glucose-dependent AgRP neuron inhibition. Therefore, distinct pathways are activated by individual macronutrients to inhibit AgRP neuron activity.
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Soty M, Vily-Petit J, Castellanos-Jankiewicz A, Guzman-Quevedo O, Raffin M, Clark S, Silva M, Gautier-Stein A, Cota D, Mithieux G. Calcitonin Gene-Related Peptide-Induced Phosphorylation of STAT3 in Arcuate Neurons Is a Link in the Metabolic Benefits of Portal Glucose. Neuroendocrinology 2021; 111:555-567. [PMID: 32516785 DOI: 10.1159/000509230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 06/08/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Intestinal gluconeogenesis (IGN) exerts metabolic benefits in energy homeostasis via the neural sensing of portal glucose. OBJECTIVE The aim of this work was to determine central mechanisms involved in the effects of IGN on the control of energy homeostasis. METHODS We investigated the effects of glucose infusion into the portal vein, at a rate that mimics IGN, in conscious wild-type, leptin-deficient Ob/Ob and calcitonin gene-related peptide (CGRP)-deficient mice. RESULTS We report that portal glucose infusion decreases food intake and plasma glucose and induces in the hypothalamic arcuate nucleus (ARC) the phosphorylation of STAT3, the classic intracellular messenger of leptin signaling. This notably takes place in POMC-expressing neurons. STAT3 phosphorylation does not require leptin, since portal glucose effects are observed in leptin-deficient Ob/Ob mice. We hypothesized that the portal glucose effects could require CGRP, a neuromediator previously suggested to suppress hunger. In line with this hypothesis, neither the metabolic benefits nor the phosphorylation of STAT3 in the ARC take place upon portal glucose infusion in CGRP-deficient mice. Moreover, intracerebroventricular injection of CGRP activates hypothalamic phosphorylation of STAT3 in mice, and CGRP does the same in hypothalamic cells. Finally, no metabolic benefit of dietary fibers (known to depend on the induction of IGN), takes place in CGRP-deficient mice. CONCLUSIONS CGRP-induced phosphorylation of STAT3 in the ARC is part of the neural chain determining the hunger-modulating and glucose-lowering effects of IGN/portal glucose.
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Affiliation(s)
- Maud Soty
- Nutrition, Diabetes, and the Brain, INSERM U1213, Lyon, France
- Université de Lyon, Lyon, France
- Université Lyon 1, Villeurbanne, France
| | - Justine Vily-Petit
- Nutrition, Diabetes, and the Brain, INSERM U1213, Lyon, France
- Université de Lyon, Lyon, France
- Université Lyon 1, Villeurbanne, France
| | - Ashley Castellanos-Jankiewicz
- Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, University of Bordeaux, INSERM U1215, Bordeaux, France
| | - Omar Guzman-Quevedo
- Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, University of Bordeaux, INSERM U1215, Bordeaux, France
| | - Margaux Raffin
- Nutrition, Diabetes, and the Brain, INSERM U1213, Lyon, France
- Université de Lyon, Lyon, France
- Université Lyon 1, Villeurbanne, France
| | - Samantha Clark
- Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, University of Bordeaux, INSERM U1215, Bordeaux, France
| | - Marine Silva
- Nutrition, Diabetes, and the Brain, INSERM U1213, Lyon, France
- Université de Lyon, Lyon, France
- Université Lyon 1, Villeurbanne, France
| | - Amandine Gautier-Stein
- Nutrition, Diabetes, and the Brain, INSERM U1213, Lyon, France
- Université de Lyon, Lyon, France
- Université Lyon 1, Villeurbanne, France
| | - Daniela Cota
- Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, University of Bordeaux, INSERM U1215, Bordeaux, France
| | - Gilles Mithieux
- Nutrition, Diabetes, and the Brain, INSERM U1213, Lyon, France,
- Université de Lyon, Lyon, France,
- Université Lyon 1, Villeurbanne, France,
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13
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Sinet F, Soty M, Zemdegs J, Guiard B, Estrada J, Malleret G, Silva M, Mithieux G, Gautier-Stein A. Dietary Fibers and Proteins Modulate Behavior via the Activation of Intestinal Gluconeogenesis. Neuroendocrinology 2021; 111:1249-1265. [PMID: 33429400 DOI: 10.1159/000514289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 01/07/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Several studies have suggested that diet, especially the one enriched in microbiota-fermented fibers or fat, regulates behavior. The underlying mechanisms are currently unknown. We previously reported that certain macronutrients (fermentable fiber and protein) regulate energy homeostasis via the activation of intestinal gluconeogenesis (IGN), which generates a neural signal to the brain. We hypothesized that these nutriments might control behavior using the same gut-brain circuit. METHODS Wild-type and IGN-deficient mice were fed chow or diets enriched in protein or fiber. Changes in their behavior were assessed using suited tests. Hippocampal neurogenesis, extracellular levels of serotonin, and protein expression levels were assessed by immunofluorescence, in vivo dialysis, and Western blotting, respectively. IGN was rescued by infusing glucose into the portal vein of IGN-deficient mice. RESULTS We show here that both fiber- and protein-enriched diets exert beneficial actions on anxiety-like and depressive-like behaviors. These benefits do not occur in mice lacking IGN. Consistently, IGN-deficient mice display hallmarks of depressive-like disorders, including decreased hippocampal neurogenesis, basal hyperactivity, and deregulation of the hypothalamic-pituitary-adrenal axis, which are associated with increased expression of the precursor of corticotropin-releasing hormone in the hypothalamus and decreased expression of the glucocorticoid receptor in the hippocampus. These neurobiological alterations are corrected by portal glucose infusion mimicking IGN. CONCLUSION IGN translates nutritional information, allowing the brain to finely coordinate energy metabolism and behavior.
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Affiliation(s)
- Flore Sinet
- INSERM UMR-S1213, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
| | - Maud Soty
- INSERM UMR-S1213, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
| | - Juliane Zemdegs
- CRCA - UMR 5169 - Université Paul Sabatier, Toulouse, France
| | - Bruno Guiard
- CRCA - UMR 5169 - Université Paul Sabatier, Toulouse, France
| | - Judith Estrada
- INSERM UMR-S1213, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
| | - Gaël Malleret
- Forgetting and Cortical Dynamics, Lyon Neuroscience Research Center, Université de Lyon, Lyon, France
| | - Marine Silva
- INSERM UMR-S1213, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
| | - Gilles Mithieux
- INSERM UMR-S1213, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
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Vily-Petit J, Soty-Roca M, Silva M, Raffin M, Gautier-Stein A, Rajas F, Mithieux G. Intestinal gluconeogenesis prevents obesity-linked liver steatosis and non-alcoholic fatty liver disease. Gut 2020; 69:2193-2202. [PMID: 32205419 DOI: 10.1136/gutjnl-2019-319745] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 02/14/2020] [Accepted: 02/28/2020] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Hepatic steatosis accompanying obesity is a major health concern, since it may initiate non-alcoholic fatty liver disease (NAFLD) and associated complications like cirrhosis or cancer. Intestinal gluconeogenesis (IGN) is a recently described function that contributes to the metabolic benefits of specific macronutrients as protein or soluble fibre, via the initiation of a gut-brain nervous signal triggering brain-dependent regulations of peripheral metabolism. Here, we investigate the effects of IGN on liver metabolism, independently of its induction by the aforementioned macronutrients. DESIGN To study the specific effects of IGN on hepatic metabolism, we used two transgenic mouse lines: one is knocked down for and the other overexpresses glucose-6-phosphatase, the key enzyme of endogenous glucose production, specifically in the intestine. RESULTS We report that mice with a genetic overexpression of IGN are notably protected from the development of hepatic steatosis and the initiation of NAFLD on a hypercaloric diet. The protection relates to a diminution of de novo lipogenesis and lipid import, associated with benefits at the level of inflammation and fibrosis and linked to autonomous nervous system. Conversely, mice with genetic suppression of IGN spontaneously exhibit increased hepatic triglyceride storage associated with activated lipogenesis pathway, in the context of standard starch-enriched diet. The latter is corrected by portal glucose infusion mimicking IGN. CONCLUSION We conclude that IGN per se has the capacity of preventing hepatic steatosis and its eventual evolution toward NAFLD.
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Affiliation(s)
- Justine Vily-Petit
- U1213 Nutrition, Diabetes and the Brain, Institut national de la santé et de la recherche médicale, Lyon, France.,U1213 Nutrition, Diabetes and the Brain, Université Lyon 1 Faculté de Médecine Lyon-Est, Lyon, France
| | - Maud Soty-Roca
- U1213 Nutrition, Diabetes and the Brain, Institut national de la santé et de la recherche médicale, Lyon, France.,U1213 Nutrition, Diabetes and the Brain, Université Lyon 1 Faculté de Médecine Lyon-Est, Lyon, France
| | - Marine Silva
- U1213 Nutrition, Diabetes and the Brain, Institut national de la santé et de la recherche médicale, Lyon, France.,U1213 Nutrition, Diabetes and the Brain, Université Lyon 1 Faculté de Médecine Lyon-Est, Lyon, France
| | - Margaux Raffin
- U1213 Nutrition, Diabetes and the Brain, Institut national de la santé et de la recherche médicale, Lyon, France.,U1213 Nutrition, Diabetes and the Brain, Université Lyon 1 Faculté de Médecine Lyon-Est, Lyon, France
| | - Amandine Gautier-Stein
- U1213 Nutrition, Diabetes and the Brain, Institut national de la santé et de la recherche médicale, Lyon, France.,U1213 Nutrition, Diabetes and the Brain, Université Lyon 1 Faculté de Médecine Lyon-Est, Lyon, France
| | - Fabienne Rajas
- U1213 Nutrition, Diabetes and the Brain, Institut national de la santé et de la recherche médicale, Lyon, France.,U1213 Nutrition, Diabetes and the Brain, Université Lyon 1 Faculté de Médecine Lyon-Est, Lyon, France
| | - Gilles Mithieux
- U1213 Nutrition, Diabetes and the Brain, Institut national de la santé et de la recherche médicale, Lyon, France .,U1213 Nutrition, Diabetes and the Brain, Université Lyon 1 Faculté de Médecine Lyon-Est, Lyon, France
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Abstract
High-protein meals and foods are promoted for their beneficial effects on satiety, weight loss and glucose homeostasis. However, the mechanisms involved and the long-term benefits of such diets are still debated. We here review how the characterisation of intestinal gluconeogenesis (IGN) sheds new light on the mechanisms by which protein diets exert their beneficial effects on health. The small intestine is the third organ (in addition to the liver and kidney) contributing to endogenous glucose production via gluconeogenesis. The particularity of glucose produced by the intestine is that it is detected in the portal vein and initiates a nervous signal to the hypothalamic nuclei regulating energy homeostasis. In this context, we demonstrated that protein diets initiate their satiety effects indirectly via IGN and portal glucose sensing. This induction results in the activation of brain areas involved in the regulation of food intake. The μ-opioid-antagonistic properties of protein digests, exerted in the portal vein, are a key link between IGN induction and protein-enriched diet in the control of satiety. From our results, IGN can be proposed as a mandatory link between nutrient sensing and the regulation of whole-body homeostasis. The use of specific mouse models targeting IGN should allow us to identify several metabolic functions that could be controlled by protein diets. This will lead to the characterisation of the mechanisms by which protein diets improve whole-body homeostasis. These data could be the basis of novel nutritional strategies targeting the serious metabolic consequences of both obesity and diabetes.
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16
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Abstract
The conscious perception of the hedonic sensory properties of caloric foods is commonly believed to guide our dietary choices. Current and traditional models implicate the consciously perceived hedonic qualities of food as driving overeating, whereas subliminal signals arising from the gut would curb our uncontrolled desire for calories. Here we review recent animal and human studies that support a markedly different model for food reward. These findings reveal in particular the existence of subcortical body-to-brain neural pathways linking gastrointestinal nutrient sensors to the brain's reward regions. Unexpectedly, consciously perceptible hedonic qualities appear to play a less relevant, and mostly transient, role in food reinforcement. In this model, gut-brain reward pathways bypass cranial taste and aroma sensory receptors and the cortical networks that give rise to flavor perception. They instead reinforce behaviors independently of the cognitive processes that support overt insights into the nature of our dietary decisions.
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Affiliation(s)
- Ivan E. de Araujo
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Modern Diet and Physiology Research Center, Yale University, New Haven, Connecticut 06511, USA
| | - Mark Schatzker
- Modern Diet and Physiology Research Center, Yale University, New Haven, Connecticut 06511, USA
| | - Dana M. Small
- Modern Diet and Physiology Research Center, Yale University, New Haven, Connecticut 06511, USA
- Departments of Psychiatry and Psychology, Yale University, New Haven, Connecticut 06511, USA
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17
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Qu T, Han W, Niu J, Tong J, de Araujo IE. On the roles of the Duodenum and the Vagus nerve in learned nutrient preferences. Appetite 2019; 139:145-151. [PMID: 31029689 DOI: 10.1016/j.appet.2019.04.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 04/17/2019] [Accepted: 04/22/2019] [Indexed: 10/27/2022]
Abstract
BACKGROUND AND AIM In most species, including humans, food preference is primarily controlled by nutrient value. However, the gut-brain pathways involved in preference learning remain elusive. The aim of the present study, performed in C57BL6/J mice, was to characterize the roles in nutrient preference of two critical elements of gut-brain pathways, i.e. the duodenum and vagal gut innervation. METHODS Adult wild-type C57BL6/J mice from a normal-weight cohort sustained one of the following three procedures: duodenal-jejunal bypass intestinal rerouting (DJB), total subdiaphragmatic vagotomy (SDV), or sham surgery. Mice were assessed in short-term two-bottle preference tests before and after 24 h s exposures to solutions containing one of glutamate, lipids, sodium, or glucose. RESULTS DJB and SDV interfered in preference formation in a nutrient-specific manner: whereas normal preference learning for lipids and glutamate was disrupted by both DJB and SDV, these interventions did not alter the formation of preferences for glucose. Interestingly, sodium preferences were abrogated by DJB but not by SDV. CONCLUSIONS Different macronutrients make use of distinct gut-brain pathways to influence food preferences, thereby mirroring nutrient-specific processes of food digestion. Specifically, whereas both vagal innervation and duodenal sensing appear critical for generating responses to fats and protein, glucose preferences recruit post-duodenal, vagal-independent pathways in pair with the control of glucose homeostasis. Overall, our data suggest that the physiological processes involved in digesting and absorbing fats, amino acids, and glucose overlap with those mediating learned preferences for each of these nutrients.
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Affiliation(s)
- Taoran Qu
- Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Shanghai, China; The John B Pierce Laboratory, New Haven, CT, USA
| | - Wenfei Han
- The John B Pierce Laboratory, New Haven, CT, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jingjing Niu
- The John B Pierce Laboratory, New Haven, CT, USA; Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Jenny Tong
- Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Ivan E de Araujo
- The John B Pierce Laboratory, New Haven, CT, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Department of Physiology, Yale University School of Arts and Sciences, New Haven, CT, USA.
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18
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Incubation of feeding behavior is regulated by neuromedin U receptor 2 in the paraventricular nucleus of the hypothalamus. Behav Brain Res 2018; 359:763-770. [PMID: 30227148 DOI: 10.1016/j.bbr.2018.08.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 08/14/2018] [Accepted: 08/15/2018] [Indexed: 01/09/2023]
Abstract
A diet of energy-dense food, characterized mainly as a high-fat diet, leads to a persistent excessive consumption defined as overeating. According to the National Institute of Health, more than 2 in 3 adults in the United States are overweight or obese, straining our healthcare system with epidemic proportions. Diets that include abstaining from high-fat foods, ironically, result in an increase in motivation and craving for said high-fat foods, defined as an incubation effect because the behavior aids in developing overeating. Previously, we have shown that modulation of neuromedin U receptor 2 (NMUR2) in the paraventricular nucleus of the hypothalamus (PVN) results in increased food intake and motivation for energy-dense foods. Here, we continue our focus on NMUR2 in the PVN, but in relation to the incubation effect on craving for high-fat food. We employed a model for incubation of craving by having rats abstain from high-fat foods for 30 days before undergoing intake of fatty food on fixed ratio and progressive ratio schedules of reinforcement, and then assess their response to reactivity to cues. Using this model, we compared the feeding behaviors of rats that underwent an mRNA knockdown of the NMUR2 in the PVN to controls after both underwent a 30-day abstinence from high-fat foods. Our results show knockdown of NMUR2 in the PVN blocks the incubation of feeding behavior for food-related cues and high-fat foods.
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Szabó I, Hormay E, Csetényi B, Nagy B, Lénárd L, Karádi Z. Multiple functional attributes of glucose-monitoring neurons in the medial orbitofrontal (ventrolateral prefrontal) cortex. Neurosci Biobehav Rev 2018; 85:44-53. [DOI: 10.1016/j.neubiorev.2017.04.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/11/2017] [Accepted: 04/21/2017] [Indexed: 11/28/2022]
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20
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Leigh SJ, Morris MJ. The role of reward circuitry and food addiction in the obesity epidemic: An update. Biol Psychol 2018; 131:31-42. [DOI: 10.1016/j.biopsycho.2016.12.013] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 10/10/2016] [Accepted: 12/15/2016] [Indexed: 12/22/2022]
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Dopamine D2 Receptor Signaling in the Nucleus Accumbens Comprises a Metabolic-Cognitive Brain Interface Regulating Metabolic Components of Glucose Reinforcement. Neuropsychopharmacology 2017; 42:2365-2376. [PMID: 28580946 PMCID: PMC5645735 DOI: 10.1038/npp.2017.112] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 05/17/2017] [Accepted: 05/19/2017] [Indexed: 12/14/2022]
Abstract
Appetitive drive is influenced by coordinated interactions between brain circuits that regulate reinforcement and homeostatic signals that control metabolism. Glucose modulates striatal dopamine (DA) and regulates appetitive drive and reinforcement learning. Striatal DA D2 receptors (D2Rs) also regulate reinforcement learning and are implicated in glucose-related metabolic disorders. Nevertheless, interactions between striatal D2R and peripheral glucose have not been previously described. Here we show that manipulations involving striatal D2R signaling coincide with perseverative and impulsive-like responding for sucrose, a disaccharide consisting of fructose and glucose. Fructose conveys orosensory (ie, taste) reinforcement but does not convey metabolic (ie, nutrient-derived) reinforcement. Glucose however conveys orosensory reinforcement but unlike fructose, it is a major metabolic energy source, underlies sustained reinforcement, and activates striatal circuitry. We found that mice with deletion of dopamine- and cAMP-regulated neuronal phosphoprotein (DARPP-32) exclusively in D2R-expressing cells exhibited preferential D2R changes in the nucleus accumbens (NAc), a striatal region that critically regulates sucrose reinforcement. These changes coincided with perseverative and impulsive-like responding for sucrose pellets and sustained reinforcement learning of glucose-paired flavors. These mice were also characterized by significant glucose intolerance (ie, impaired glucose utilization). Systemic glucose administration significantly attenuated sucrose operant responding and D2R activation or blockade in the NAc bidirectionally modulated blood glucose levels and glucose tolerance. Collectively, these results implicate NAc D2R in regulating both peripheral glucose levels and glucose-dependent reinforcement learning behaviors and highlight the notion that glucose metabolic impairments arising from disrupted NAc D2R signaling are involved in compulsive and perseverative feeding behaviors.
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22
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Sasaki T. Neural and Molecular Mechanisms Involved in Controlling the Quality of Feeding Behavior: Diet Selection and Feeding Patterns. Nutrients 2017; 9:nu9101151. [PMID: 29053636 PMCID: PMC5691767 DOI: 10.3390/nu9101151] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 10/12/2017] [Accepted: 10/13/2017] [Indexed: 12/20/2022] Open
Abstract
We are what we eat. There are three aspects of feeding: what, when, and how much. These aspects represent the quantity (how much) and quality (what and when) of feeding. The quantitative aspect of feeding has been studied extensively, because weight is primarily determined by the balance between caloric intake and expenditure. In contrast, less is known about the mechanisms that regulate the qualitative aspects of feeding, although they also significantly impact the control of weight and health. However, two aspects of feeding quality relevant to weight loss and weight regain are discussed in this review: macronutrient-based diet selection (what) and feeding pattern (when). This review covers the importance of these two factors in controlling weight and health, and the central mechanisms that regulate them. The relatively limited and fragmented knowledge on these topics indicates that we lack an integrated understanding of the qualitative aspects of feeding behavior. To promote better understanding of weight control, research efforts must focus more on the mechanisms that control the quality and quantity of feeding behavior. This understanding will contribute to improving dietary interventions for achieving weight control and for preventing weight regain following weight loss.
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Affiliation(s)
- Tsutomu Sasaki
- Laboratory for Metabolic Signaling, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma 371-8512, Japan.
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Patrono E, Matsumoto J, Nishimaru H, Takamura Y, Chinzorig IC, Ono T, Nishijo H. Rewarding Effects of Operant Dry-Licking Behavior on Neuronal Firing in the Nucleus Accumbens Core. Front Pharmacol 2017; 8:536. [PMID: 28860992 PMCID: PMC5559468 DOI: 10.3389/fphar.2017.00536] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 08/02/2017] [Indexed: 01/26/2023] Open
Abstract
Certain eating behaviors are characterized by a trend of elevated food consumption. However, neural mechanisms mediating the motivation for food consumption are not fully understood. Food impacts the brain-rewarding-system via both oral-sensory and post-ingestive information. Recent studies have reported an important role of visceral gut information in mediating dopamine (DA) release in the brain rewarding system. This is independent of oral sensation, suggesting a role of the gut-brain-DA-axis in feeding behavior. In this study, we investigated the effects of intra-gastric (IG) self-administration of glucose on neuronal firings in the nucleus accumbens (NA) of water-deprived rats. Rats were trained in an operant-licking paradigm. During training, when the light was on for 2 min (light-period), rats were required to lick a spout to acquire the water oral-intake learning, and either an IG self-infusion of 0.4 M glucose (GLU group) or water (H2O group). Rats rested in the dark-period (3 min) following the light-period. Four cycles of the operant-licking paradigm consisting of the light–dark periods were performed per day, for 4 consecutive days. In the test session, the same rats licked the same spout to acquire the IG self-administration of the corresponding solutions, without oral water ingestion (dry licking). Behavioral results indicated IG self-administration of glucose elicits more dry-licking behavior than that of water. Neurophysiological results indicated in the dark period, coefficient of variance (CV) measuring the inter-spike interval variability of putative medial spiny neurons (pMSNs) in the NA was reduced in the H2O group compared to the GLU group, while there was no significant difference in physical behaviors in the dark period between the two groups. Since previous studies reported that DA release increases CV of MSNs, the present results suggest that greater CV of pMSNs in the GLU group reflects greater DA release in the NA and elevated motivation in the GLU group, which might increase lickings in the test session in the GLU group compared to the H2O group.
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Affiliation(s)
- Enrico Patrono
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Jumpei Matsumoto
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Hiroshi Nishimaru
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Yusaku Takamura
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Ikhruud C Chinzorig
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Taketoshi Ono
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Hisao Nishijo
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
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Abstract
Intestinal gluconeogenesis is a recently identified function influencing energy homeostasis. Intestinal gluconeogenesis induced by specific nutrients releases glucose, which is sensed by the nervous system surrounding the portal vein. This initiates a signal positively influencing parameters involved in glucose control and energy management controlled by the brain. This knowledge has extended our vision of the gut-brain axis, classically ascribed to gastrointestinal hormones. Our work raises several questions relating to the conditions under which intestinal gluconeogenesis proceeds and may provide its metabolic benefits. It also leads to questions on the advantage conferred by its conservation through a process of natural selection.
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Affiliation(s)
- Maud Soty
- Institut National de la Santé et de la Recherche Médicale, U1213, Lyon 69372, France; Université de Lyon, Lyon 69008, France; Université Lyon I, Villeurbanne 69622, France
| | - Amandine Gautier-Stein
- Institut National de la Santé et de la Recherche Médicale, U1213, Lyon 69372, France; Université de Lyon, Lyon 69008, France; Université Lyon I, Villeurbanne 69622, France
| | - Fabienne Rajas
- Institut National de la Santé et de la Recherche Médicale, U1213, Lyon 69372, France; Université de Lyon, Lyon 69008, France; Université Lyon I, Villeurbanne 69622, France
| | - Gilles Mithieux
- Institut National de la Santé et de la Recherche Médicale, U1213, Lyon 69372, France; Université de Lyon, Lyon 69008, France; Université Lyon I, Villeurbanne 69622, France.
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Van Steenbergen A, Balteau M, Ginion A, Ferté L, Battault S, Ravenstein CDMD, Balligand JL, Daskalopoulos EP, Gilon P, Despa F, Despa S, Vanoverschelde JL, Horman S, Koepsell H, Berry G, Hue L, Bertrand L, Beauloye C. Sodium-myoinositol cotransporter-1, SMIT1, mediates the production of reactive oxygen species induced by hyperglycemia in the heart. Sci Rep 2017; 7:41166. [PMID: 28128227 PMCID: PMC5269587 DOI: 10.1038/srep41166] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 12/16/2016] [Indexed: 01/04/2023] Open
Abstract
Hyperglycemia (HG) stimulates the production of reactive oxygen species in the heart through activation of NADPH oxidase 2 (NOX2). This production is independent of glucose metabolism but requires sodium/glucose cotransporters (SGLT). Seven SGLT isoforms (SGLT1 to 6 and sodium-myoinositol cotransporter-1, SMIT1) are known, although their expression and function in the heart remain elusive. We investigated these 7 isoforms and found that only SGLT1 and SMIT1 were expressed in mouse, rat and human hearts. In cardiomyocytes, galactose (transported through SGLT1) did not activate NOX2. Accordingly, SGLT1 deficiency did not prevent HG-induced NOX2 activation, ruling it out in the cellular response to HG. In contrast, myo-inositol (transported through SMIT1) reproduced the toxic effects of HG. SMIT1 overexpression exacerbated glucotoxicity and sensitized cardiomyocytes to HG, whereas its deletion prevented HG-induced NOX2 activation. In conclusion, our results show that heart SMIT1 senses HG and triggers NOX2 activation. This could participate in the redox signaling in hyperglycemic heart and contribute to the pathophysiology of diabetic cardiomyopathy.
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Affiliation(s)
- Anne Van Steenbergen
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Magali Balteau
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Audrey Ginion
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Laura Ferté
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Sylvain Battault
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | | | - Jean-Luc Balligand
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Pharmacology and Therapeutics, Brussels, Belgium.,Cliniques Universitaires Saint-Luc, Department of Medicine, Brussels, Belgium
| | - Evangelos-Panagiotis Daskalopoulos
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Patrick Gilon
- Université Catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle d'Endocrinologie, Diabète et Nutrition, Brussels, Belgium
| | - Florin Despa
- University of Kentucky, Department of Pharmacology and Nutritional Sciences, Lexington, KY, USA
| | - Sanda Despa
- University of Kentucky, Department of Pharmacology and Nutritional Sciences, Lexington, KY, USA
| | - Jean-Louis Vanoverschelde
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium.,Cliniques Universitaires Saint Luc, Division of Cardiology, Brussels, Belgium
| | - Sandrine Horman
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Hermann Koepsell
- University of Würzburg, Department of Molecular Plant Physiology and Biophysics, Julius von Sachs Institute, Würzburg, Germany
| | - Gerard Berry
- Harvard Medical School, Children's Hospital Boston, Division of Genetics and Genomics, Department of Pediatrics, Boston, MA, USA
| | - Louis Hue
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium.,Université catholique de Louvain, de Duve Institute, Brussels, Belgium
| | - Luc Bertrand
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Christophe Beauloye
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium.,Cliniques Universitaires Saint Luc, Division of Cardiology, Brussels, Belgium
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26
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McCue DL, Kasper JM, Hommel JD. Regulation of motivation for food by neuromedin U in the paraventricular nucleus and the dorsal raphe nucleus. Int J Obes (Lond) 2017; 41:120-128. [PMID: 27748746 PMCID: PMC5209284 DOI: 10.1038/ijo.2016.178] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 09/02/2016] [Accepted: 09/13/2016] [Indexed: 12/02/2022]
Abstract
BACKGROUND Motivation for high-fat food is thought to contribute to excess caloric intake in obese individuals. A novel regulator of motivation for food may be neuromedin U (NMU), a highly-conserved neuropeptide that influences food intake. Although these effects of NMU have primarily been attributed to signaling in the paraventricular nucleus of the hypothalamus (PVN), NMU has also been found in other brain regions involved in both feeding behavior and motivation. We investigate the effects of NMU on motivation for food and food intake, and identify the brain regions mediating these effects. METHODS The motivational state for a particular reinforcer (e.g., high-fat food) can be assessed using a progressive-ratio schedule of reinforcement under which an increasing number of lever presses are required to obtain subsequent reinforcers. Here, we have used a progressive-ratio operant responding paradigm in combination with an assessment of cumulative food intake to evaluate the effects of NMU administration in rats, and identify the brain regions mediating these effects. RESULTS We found that peripheral administration of NMU decreases operant responding for high-fat food in rats. Evaluation of Fos-like immunoreactivity in response to peripheral NMU indicated the PVN and dorsal raphe nucleus (DRN) as sites of action for NMU. NMU infusion into either region mimics the effects of peripheral NMU on food intake and operant responding for food. NMU-containing projections from the lateral hypothalamus (LH) to the PVN and DRN were identified as an endogenous source of NMU. CONCLUSIONS These results identify the DRN as a site of action for NMU, demonstrate that the LH provides endogenous NMU to the PVN and DRN and implicate NMU signaling in the PVN and DRN as a novel regulator of motivation for high-fat foods.
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Affiliation(s)
- David L. McCue
- Department of Neuroscience, University of Texas Medical Branch, Galveston, TX 77555-0615
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555-0615
| | - James M. Kasper
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555-0615
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555-0615
| | - Jonathan D. Hommel
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555-0615
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555-0615
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27
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Devarakonda K, Mobbs CV. Mechanisms and significance of brain glucose signaling in energy balance, glucose homeostasis, and food-induced reward. Mol Cell Endocrinol 2016; 438:61-69. [PMID: 27637346 DOI: 10.1016/j.mce.2016.09.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 09/12/2016] [Accepted: 09/12/2016] [Indexed: 12/15/2022]
Abstract
The concept that hypothalamic glucose signaling plays an important role in regulating energy balance, e.g., as instantiated in the so-called "glucostat" hypothesis, is one of the oldest in the field of metabolism. However the mechanisms by which neurons in the hypothalamus sense glucose, and the function of glucose signaling in the brain, has been difficult to establish. Nevertheless recent studies probing mechanisms of glucose signaling have also strongly supported a role for glucose signaling in regulating energy balance, glucose homeostasis, and food-induced reward.
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Affiliation(s)
- Kavya Devarakonda
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, 1470 Madison Ave., 9-119, New York, NY 10029, USA; Department of Endocrinology, Icahn School of Medicine at Mount Sinai, 1470 Madison Ave., 9-119, New York, NY 10029, USA
| | - Charles V Mobbs
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, 1470 Madison Ave., 9-119, New York, NY 10029, USA; Department of Endocrinology, Icahn School of Medicine at Mount Sinai, 1470 Madison Ave., 9-119, New York, NY 10029, USA; Department of Geriatrics, Icahn School of Medicine at Mount Sinai, 1470 Madison Ave., 9-119, New York, NY 10029, USA.
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28
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Bojanowska E, Ciosek J. Can We Selectively Reduce Appetite for Energy-Dense Foods? An Overview of Pharmacological Strategies for Modification of Food Preference Behavior. Curr Neuropharmacol 2016; 14:118-42. [PMID: 26549651 PMCID: PMC4825944 DOI: 10.2174/1570159x14666151109103147] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 09/19/2015] [Accepted: 10/31/2015] [Indexed: 12/11/2022] Open
Abstract
Excessive intake of food, especially palatable and energy-dense carbohydrates and fats, is
largely responsible for the growing incidence of obesity worldwide. Although there are a number of
candidate antiobesity drugs, only a few of them have been proven able to inhibit appetite for palatable
foods without the concurrent reduction in regular food consumption. In this review, we discuss the
interrelationships between homeostatic and hedonic food intake control mechanisms in promoting
overeating with palatable foods and assess the potential usefulness of systemically administered pharmaceuticals that
impinge on the endogenous cannabinoid, opioid, aminergic, cholinergic, and peptidergic systems in the modification of
food preference behavior. Also, certain dietary supplements with the potency to reduce specifically palatable food intake
are presented. Based on human and animal studies, we indicate the most promising therapies and agents that influence the
effectiveness of appetite-modifying drugs. It should be stressed, however, that most of the data included in our review
come from preclinical studies; therefore, further investigations aimed at confirming the effectiveness and safety of the
aforementioned medications in the treatment of obese humans are necessary.
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Affiliation(s)
- Ewa Bojanowska
- Department of Behavioral Pathophysiology, Institute of General and Experimental Pathology, Medical University of Lodz, 60 Narutowicza Street, 90-136 Lodz, Poland.
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29
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Riera CE, Dillin A. Emerging Role of Sensory Perception in Aging and Metabolism. Trends Endocrinol Metab 2016; 27:294-303. [PMID: 27067041 DOI: 10.1016/j.tem.2016.03.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 03/10/2016] [Accepted: 03/10/2016] [Indexed: 12/26/2022]
Abstract
Sensory perception comprises gustatory (taste) and olfactory (smell) modalities as well as somatosensory (pain, heat, and tactile mechanosensory) inputs, which are detected by a multitude of sensory receptors. These sensory receptors are contained in specialized ciliated neurons where they detect changes in environmental conditions and participate in behavioral decisions ranging from food choice to avoiding harmful conditions, thus insuring basic survival in metazoans. Recent genetic studies, however, indicate that sensory perception plays additional physiological functions, notably influencing energy homeostatic processes and longevity through neuronal circuits originating from sensory tissues. Here we review how these findings are redefining metabolic signaling and establish a prominent role of sensory neuroendocrine processes in controlling health span and lifespan, with a goal of translating this knowledge towards managing age-associated diseases.
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Affiliation(s)
- Celine E Riera
- Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Glenn Center for Research on Aging, University of California, Berkeley, Berkeley, CA, USA
| | - Andrew Dillin
- Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Glenn Center for Research on Aging, University of California, Berkeley, Berkeley, CA, USA.
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30
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Circuit organization of sugar reinforcement. Physiol Behav 2016; 164:473-477. [PMID: 27126968 DOI: 10.1016/j.physbeh.2016.04.041] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/23/2016] [Accepted: 04/23/2016] [Indexed: 12/29/2022]
Abstract
Sugar's potent reinforcing properties arise from the complex interplay between gustatory and nutritive signals. This commentary addresses a unique organizational aspect of the neuronal circuitry that mediates sugar reinforcement in both Drosophila and rodents. Specifically, current evidence supports a general circuit model where separate populations of dopaminergic neurons encode the gustatory and nutritive values of sugar. This arrangement allows animals to prioritize energy seeking over taste quality, and implies that specialized subpopulations of dopamine-containing neurons form a class of evolutionary conserved chemo- and nutrient-sensors.
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31
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Daniels S, Marshall P, Leri F. Alterations of naltrexone-induced conditioned place avoidance by pre-exposure to high fructose corn syrup or heroin in Sprague-Dawley rats. Psychopharmacology (Berl) 2016; 233:425-33. [PMID: 26514556 DOI: 10.1007/s00213-015-4121-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 10/13/2015] [Indexed: 11/30/2022]
Abstract
RATIONALE It has been suggested that withdrawal from sugar produces a set of symptoms that resemble those observed following withdrawal from opiate drugs. OBJECTIVES This study explored naltrexone-induced withdrawal in animals pre-exposed to acute, chronic, and intermittent high fructose corn syrup (HFCS) or acute and chronic heroin administration. METHODS Experiment 1 examined conditioned place avoidance (CPA) induced by different doses of naltrexone (0.01-1 mg/kg) in naïve male Sprague-Dawley rats. In experiment 2, rats received continuous or intermittent home cage HFCS access (0 or 50 %) prior to conditioning with 1 mg/kg naltrexone. In experiment 3, HFCS ingestion was increased by food restriction and rats were conditioned with 3 mg/kg naltrexone. In experiment 4, the timing and quantity of HFCS ingestion (0, 0.5, 1, 2 g/kg) was controlled by intragastric administration, and rats were conditioned with 1 mg/kg naltrexone. In experiment 5, rats received acute (2 mg/kg) or chronic heroin (3.5 mg/kg/day) prior to conditioning with 1 mg/kg naltrexone. RESULTS Administration of naltrexone produced moderate conditioned place avoidance in naïve rats. Importantly, acute, continuous, and intermittent HFCS pre-exposure did not significantly amplify this effect, but acute and chronic heroin pre-exposure did. CONCLUSIONS As assessed by CPA, these results in rats fail to support the hypothesis that an opioid antagonist can precipitate similar affective withdrawal states following pre-exposure to sugars and opiates.
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Affiliation(s)
- Stephen Daniels
- Department of Psychology, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Paul Marshall
- Department of Psychology, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Francesco Leri
- Department of Psychology, University of Guelph, Guelph, ON, N1G 2W1, Canada.
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32
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The inactivation of extracellular signal-regulated kinase by glucagon-like peptide-1 contributes to neuroprotection against oxidative stress. Neurosci Lett 2016; 616:105-10. [PMID: 26827720 DOI: 10.1016/j.neulet.2016.01.052] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/19/2016] [Accepted: 01/26/2016] [Indexed: 01/17/2023]
Abstract
Glucagon-like peptide-1 (GLP-1), an insulinotropic peptide secreted from enteroendocrine cells, has been known to have a neuroprotective effect. However, it is not fully understood the intracellular mediator of GLP-1 signaling in neuronal cells. In the present study, we examined the change in intracellular signaling of cortical neurons after GLP-1 application and luminal glucose stimulation in vitro and in vivo. GLP-1 receptor was highly expressed in cultured cortical neurons and brain tissues including the prefrontal cortex and hippocampus. The activation of GLP-1 receptor (5min) significantly decreased levels of phosphorylated extracellular signal-regulated kinase (pERK), which is involved in neuronal cell survival and death, in cultured cortical neurons. Oral glucose administration also rapidly reduced pERK levels in the prefrontal cortex, while intraperitoneal glucose injection did not show such an effect. Further, GLP-1 attenuated hydrogen peroxide-induced cell death and hyperactivity of ERK in cultured cortical neurons. It is possible that increased GLP-1 by luminal glucose stimulation affects cortical system including the maintenance of neuronal cell survival.
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33
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Han W, Tellez LA, Niu J, Medina S, Ferreira TL, Zhang X, Su J, Tong J, Schwartz GJ, van den Pol A, de Araujo IE. Striatal Dopamine Links Gastrointestinal Rerouting to Altered Sweet Appetite. Cell Metab 2016; 23:103-12. [PMID: 26698915 PMCID: PMC4715689 DOI: 10.1016/j.cmet.2015.10.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 07/04/2015] [Accepted: 10/19/2015] [Indexed: 12/01/2022]
Abstract
Reductions in calorie intake contribute significantly to the positive outcome of bariatric surgeries. However, the physiological mechanisms linking the rerouting of the gastrointestinal tract to reductions in sugar cravings remain uncertain. We show that a duodenal-jejunal bypass (DJB) intervention inhibits maladaptive sweet appetite by acting on dopamine-responsive striatal circuitries. DJB disrupted the ability of recurrent sugar exposure to promote sweet appetite in sated animals, thereby revealing a link between recurrent duodenal sugar influx and maladaptive sweet intake. Unlike ingestion of a low-calorie sweetener, ingestion of sugar was associated with significant dopamine effluxes in the dorsal striatum, with glucose infusions into the duodenum inducing greater striatal dopamine release than equivalent jejunal infusions. Consistently, optogenetic activation of dopamine-excitable cells of the dorsal striatum was sufficient to restore maladaptive sweet appetite in sated DJB mice. Our findings point to a causal link between striatal dopamine signaling and the outcomes of bariatric interventions.
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Affiliation(s)
- Wenfei Han
- Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Shanghai 200072, China; The John B. Pierce Laboratory, New Haven, CT 06519, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, USA
| | - Luis A Tellez
- The John B. Pierce Laboratory, New Haven, CT 06519, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, USA
| | - Jingjing Niu
- The John B. Pierce Laboratory, New Haven, CT 06519, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, USA; Division of Endocrinology, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Sara Medina
- The John B. Pierce Laboratory, New Haven, CT 06519, USA
| | - Tatiana L Ferreira
- The John B. Pierce Laboratory, New Haven, CT 06519, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, USA; Mathematics, Computing and Cognition Center, Federal University of ABC, Santo André 09210, Brazil
| | - Xiaobing Zhang
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06519, USA
| | - Jiansheng Su
- Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Shanghai 200072, China
| | - Jenny Tong
- Division of Endocrinology, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Gary J Schwartz
- Albert Einstein College of Medicine, Yeshiva University, Bronx, NY 10461, USA
| | - Anthony van den Pol
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06519, USA
| | - Ivan E de Araujo
- The John B. Pierce Laboratory, New Haven, CT 06519, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, USA; Department of Physiology, Yale University School of Arts and Sciences, New Haven, CT 06511, USA.
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34
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Dixon JB, Lambert EA, Lambert GW. Neuroendocrine adaptations to bariatric surgery. Mol Cell Endocrinol 2015; 418 Pt 2:143-52. [PMID: 26044866 DOI: 10.1016/j.mce.2015.05.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 04/16/2015] [Accepted: 05/04/2015] [Indexed: 02/07/2023]
Abstract
The global epidemic of obesity and its related disease in combination with robust physiological defence of intentional weight loss generates a pressing need for effective weight loss therapies. Bariatric surgery, which works very effectively at delivering substantial sustained weight loss, has been an enigma with respect to mechanism of action. Naive concepts of restriction and malabsorption do not explain the efficacy of the most commonly used bariatric procedures. This century has seen increased interest in unravelling the mystery of the mechanisms underlying surgery associated weight loss with a focus on integrative gastrointestinal (GI) physiology, gut-brain signalling, and beyond weight loss effects on metabolism. GI interventions, some very minor, can alter GI wall stretch and pressure receptors; a range of GI hormones affecting hunger and satiety; bile acid metabolism and signalling; the characteristics of GI microbiome; portal vein nutrient sensing; and circulating concentrations of amino acids. Understanding the mechanisms involved should present targets for less invasive effective therapies.
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Affiliation(s)
- J B Dixon
- Baker IDI Heart & Diabetes Institute, 75 Commercial Road, Melbourne, VIC 3004, Australia.
| | - E A Lambert
- Baker IDI Heart & Diabetes Institute, 75 Commercial Road, Melbourne, VIC 3004, Australia
| | - G W Lambert
- Baker IDI Heart & Diabetes Institute, 75 Commercial Road, Melbourne, VIC 3004, Australia
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35
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Steinbusch L, Labouèbe G, Thorens B. Brain glucose sensing in homeostatic and hedonic regulation. Trends Endocrinol Metab 2015; 26:455-66. [PMID: 26163755 DOI: 10.1016/j.tem.2015.06.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 06/15/2015] [Accepted: 06/16/2015] [Indexed: 11/21/2022]
Abstract
Glucose homeostasis as well as homeostatic and hedonic control of feeding is regulated by hormonal, neuronal, and nutrient-related cues. Glucose, besides its role as a source of metabolic energy, is an important signal controlling hormone secretion and neuronal activity, hence contributing to whole-body metabolic integration in coordination with feeding control. Brain glucose sensing plays a key, but insufficiently explored, role in these metabolic and behavioral controls, which when deregulated may contribute to the development of obesity and diabetes. The recent introduction of innovative transgenic, pharmacogenetic, and optogenetic techniques allows unprecedented analysis of the complexity of central glucose sensing at the molecular, cellular, and neuronal circuit levels, which will lead to a new understanding of the pathogenesis of metabolic diseases.
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Affiliation(s)
- Laura Steinbusch
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Gwenaël Labouèbe
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Bernard Thorens
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland.
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36
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De Vadder F, Mithieux G. Contrôle de la glycémie par l’axe nerveux intestin-cerveau. Med Sci (Paris) 2015; 31:168-73. [DOI: 10.1051/medsci/20153102013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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37
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Soty M, Penhoat A, Amigo-Correig M, Vinera J, Sardella A, Vullin-Bouilloux F, Zitoun C, Houberdon I, Mithieux G. A gut-brain neural circuit controlled by intestinal gluconeogenesis is crucial in metabolic health. Mol Metab 2014; 4:106-17. [PMID: 25685698 PMCID: PMC4314540 DOI: 10.1016/j.molmet.2014.12.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 12/17/2014] [Accepted: 12/18/2014] [Indexed: 12/19/2022] Open
Abstract
Objectives Certain nutrients positively regulate energy homeostasis via intestinal gluconeogenesis (IGN). The objective of this study was to evaluate the impact of a deficient IGN in glucose control independently of nutritional environment. Methods We used mice deficient in the intestine glucose-6 phosphatase catalytic unit, the key enzyme of IGN (I-G6pc−/− mice). We evaluated a number of parameters involved in energy homeostasis, including insulin sensitivity (hyperinsulinemic euglycaemic clamp), the pancreatic function (insulin secretion in vivo and in isolated islets) and the hypothalamic homeostatic function (leptin sensitivity). Results Intestinal-G6pc−/− mice exhibit slight fasting hyperglycaemia and hyperinsulinemia, glucose intolerance, insulin resistance and a deteriorated pancreatic function, despite normal diet with no change in body weight. These defects evoking type 2 diabetes (T2D) derive from the basal activation of the sympathetic nervous system (SNS). They are corrected by treatment with an inhibitor of α-2 adrenergic receptors. Deregulation in a key target of IGN, the homeostatic hypothalamic function (highlighted here through leptin resistance) is a mechanistic link. Hence the leptin resistance and metabolic disorders in I-G6pc−/− mice are corrected by rescuing IGN by portal glucose infusion. Finally, I-G6pc−/− mice develop the hyperglycaemia characteristic of T2D more rapidly under high fat/high sucrose diet. Conclusions Intestinal gluconeogenesis is a mandatory function for the healthy neural control of glucose homeostasis.
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Affiliation(s)
- Maud Soty
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
| | - Armelle Penhoat
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
| | - Marta Amigo-Correig
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
| | - Jennifer Vinera
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
| | - Anne Sardella
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
| | - Fanny Vullin-Bouilloux
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
| | - Carine Zitoun
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
| | - Isabelle Houberdon
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
| | - Gilles Mithieux
- Institut National de la Santé et de la Recherche Médicale, U855, Lyon, F-69008, France
- Université de Lyon, Lyon, F-69008, France
- Université Lyon1, Villeurbanne, F-69622, France
- Corresponding author. Inserm U855, Faculté de Médecine Laennec, 7 rue Guillaume Paradin, 69372, Lyon cedex 08, France. Tel.: +33 478 77 10 28; fax: +33 478 77 87 62.
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38
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Abstract
Brain glucosensing neurons monitor extracellular glucose concentrations and act to defend normoglycemia. To date, the majority of these neurons have been ascribed to hypothalamic and hindbrain centers. In this issue, Garfield and colleagues (2014) demonstrate that cholecystokinin-expressing neurons in the rodent parabrachial nucleus function as glucosensors that counter-regulate hypoglycemia.
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Soria-Gomez E, Bellocchio L, Marsicano G. New insights on food intake control by olfactory processes: the emerging role of the endocannabinoid system. Mol Cell Endocrinol 2014; 397:59-66. [PMID: 25261796 DOI: 10.1016/j.mce.2014.09.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 09/22/2014] [Accepted: 09/22/2014] [Indexed: 01/06/2023]
Abstract
The internal state of the organism is an important modulator of perception and behavior. The link between hunger, olfaction and feeding behavior is one of the clearest examples of these connections. At the neurobiological level, olfactory circuits are the targets of several signals (i.e. hormones and nutrients) involved in energy balance. This indicates that olfactory areas are potential sensors of the internal state of the organism. Thus, the aim of this manuscript is to review the literature showing the interplay between metabolic signals in olfactory circuits and its impact on food intake.
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Affiliation(s)
- Edgar Soria-Gomez
- INSERM, U862 NeuroCentre Magendie, Endocannabinoids and Neuroadaptation, Bordeaux, France.
| | - Luigi Bellocchio
- Dept. of Biochemistry and Molecular Biology I, Sch. of Biology, Complutense Univ. and CIBERNED, Madrid, Spain
| | - Giovanni Marsicano
- INSERM, U862 NeuroCentre Magendie, Endocannabinoids and Neuroadaptation, Bordeaux, France
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40
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Ogunnowo-Bada EO, Heeley N, Brochard L, Evans ML. Brain glucose sensing, glucokinase and neural control of metabolism and islet function. Diabetes Obes Metab 2014; 16 Suppl 1:26-32. [PMID: 25200293 PMCID: PMC4405079 DOI: 10.1111/dom.12334] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Accepted: 06/05/2014] [Indexed: 11/30/2022]
Abstract
It is increasingly apparent that the brain plays a central role in metabolic homeostasis, including the maintenance of blood glucose. This is achieved by various efferent pathways from the brain to periphery, which help control hepatic glucose flux and perhaps insulin-stimulated insulin secretion. Also, critically important for the brain given its dependence on a constant supply of glucose as a fuel--emergency counter-regulatory responses are triggered by the brain if blood glucose starts to fall. To exert these control functions, the brain needs to detect rapidly and accurately changes in blood glucose. In this review, we summarize some of the mechanisms postulated to play a role in this and examine the potential role of the low-affinity hexokinase, glucokinase, in the brain as a key part of some of this sensing. We also discuss how these processes may become altered in diabetes and related metabolic diseases.
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Affiliation(s)
- E O Ogunnowo-Bada
- Wellcome Trust-MRC Institute of Metabolic Science, IMS Metabolic Research Laboratories, University of CambridgeCambridge, UK
| | - N Heeley
- Wellcome Trust-MRC Institute of Metabolic Science, IMS Metabolic Research Laboratories, University of CambridgeCambridge, UK
| | - L Brochard
- Wellcome Trust-MRC Institute of Metabolic Science, IMS Metabolic Research Laboratories, University of CambridgeCambridge, UK
| | - M L Evans
- Wellcome Trust-MRC Institute of Metabolic Science, IMS Metabolic Research Laboratories, University of CambridgeCambridge, UK
- Correspondence to: Mark Evans, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, IMS Metabolic Research Laboratories, Box 289 Addenbrookes Hospital, Hills Road, Cambridge CB2 0QQ, UK. E-mail:
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