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Takenoya F, Shibato J, Yamashita M, Kimura A, Hirako S, Chiba Y, Nonaka N, Shioda S, Rakwal R. Transcriptomic (DNA Microarray) and Metabolome (LC-TOF-MS) Analyses of the Liver in High-Fat Diet Mice after Intranasal Administration of GALP (Galanin-like Peptide). Int J Mol Sci 2023; 24:15825. [PMID: 37958806 PMCID: PMC10648535 DOI: 10.3390/ijms242115825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/20/2023] [Accepted: 10/28/2023] [Indexed: 11/15/2023] Open
Abstract
The aim of this research was to test the efficacy and potential clinical application of intranasal administration of galanin-like peptide (GALP) as an anti-obesity treatment under the hypothesis that GALP prevents obesity in mice fed a high-fat diet (HFD). Focusing on the mechanism of regulation of lipid metabolism in peripheral tissues via the autonomic nervous system, we confirmed that, compared with a control (saline), intranasally administered GALP prevented further body weight gain in diet-induced obesity (DIO) mice with continued access to an HFD. Using an omics-based approach, we identified several genes and metabolites in the liver tissue of DIO mice that were altered by the administration of intranasal GALP. We used whole-genome DNA microarray and metabolomics analyses to determine the anti-obesity effects of intranasal GALP in DIO mice fed an HFD. Transcriptomic profiling revealed the upregulation of flavin-containing dimethylaniline monooxygenase 3 (Fmo3), metallothionein 1 and 2 (Mt1 and Mt2, respectively), and the Aldh1a3, Defa3, and Defa20 genes. Analysis using the DAVID tool showed that intranasal GALP enhanced gene expression related to fatty acid elongation and unsaturated fatty acid synthesis and downregulated gene expression related to lipid and cholesterol synthesis, fat absorption, bile uptake, and excretion. Metabolite analysis revealed increased levels of coenzyme Q10 and oleoylethanolamide in the liver tissue, increased levels of deoxycholic acid (DCA) and taurocholic acid (TCA) in the bile acids, increased levels of taurochenodeoxycholic acid (TCDCA), and decreased levels of ursodeoxycholic acid (UDCA). In conclusion, intranasal GALP administration alleviated weight gain in obese mice fed an HFD via mechanisms involving antioxidant, anti-inflammatory, and fatty acid metabolism effects and genetic alterations. The gene expression data are publicly available at NCBI GSE243376.
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Affiliation(s)
- Fumiko Takenoya
- Department of Sport Sciences, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo 142-8501, Japan; (F.T.); (M.Y.); (A.K.)
| | - Junko Shibato
- Department of Functional Morphology, Shonan University of Medical Sciences, Kanagawa 244-0806, Japan; (J.S.); (S.S.)
| | - Michio Yamashita
- Department of Sport Sciences, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo 142-8501, Japan; (F.T.); (M.Y.); (A.K.)
| | - Ai Kimura
- Department of Sport Sciences, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo 142-8501, Japan; (F.T.); (M.Y.); (A.K.)
| | - Satoshi Hirako
- Department of Health and Nutrition, University of Human Arts and Sciences, Saitama 339-8539, Japan;
| | - Yoshihiko Chiba
- Laboratory of Molecular Biology and Physiology, School of Pharmacy, Hoshi University, Tokyo 142-8501, Japan;
| | - Naoko Nonaka
- Department of Oral Anatomy and Developmental Biology, Showa University School of Dentistry, Tokyo 142-8555, Japan;
| | - Seiji Shioda
- Department of Functional Morphology, Shonan University of Medical Sciences, Kanagawa 244-0806, Japan; (J.S.); (S.S.)
| | - Randeep Rakwal
- Institute of Health and Sport Sciences, University of Tsukuba, Tsukuba 305-8574, Japan
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2
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Romano A, Friuli M, Eramo B, Gallelli CA, Koczwara JB, Azari EK, Paquot A, Arnold M, Langhans W, Muccioli GG, Lutz TA, Gaetani S. "To brain or not to brain": evaluating the possible direct effects of the satiety factor oleoylethanolamide in the central nervous system. Front Endocrinol (Lausanne) 2023; 14:1158287. [PMID: 37234803 PMCID: PMC10206109 DOI: 10.3389/fendo.2023.1158287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 04/12/2023] [Indexed: 05/28/2023] Open
Abstract
Introduction Oleoylethanolamide (OEA), an endogenous N-acylethanolamine acting as a gut-to-brain signal to control food intake and metabolism, has been attracting attention as a target for novel therapies against obesity and eating disorders. Numerous observations suggested that the OEA effects might be peripherally mediated, although they involve central pathways including noradrenergic, histaminergic and oxytocinergic systems of the brainstem and the hypothalamus. Whether these pathways are activated directly by OEA or whether they are downstream of afferent nerves is still highly debated. Some early studies suggested vagal afferent fibers as the main route, but our previous observations have contradicted this idea and led us to consider the blood circulation as an alternative way for OEA's central actions. Methods To test this hypothesis, we first investigated the impact of subdiaphragmatic vagal deafferentation (SDA) on the OEA-induced activation of selected brain nuclei. Then, we analyzed the pattern of OEA distribution in plasma and brain at different time points after intraperitoneal administration in addition to measuring food intake. Results Confirming and extending our previous findings that subdiaphragmatic vagal afferents are not necessary for the eating-inhibitory effect of exogenous OEA, our present results demonstrate that vagal sensory fibers are also not necessary for the neurochemical effects of OEA. Rather, within a few minutes after intraperitoneal administration, we found an increased concentration of intact OEA in different brain areas, associated with the inhibition of food intake. Conclusion Our results support that systemic OEA rapidly reaches the brain via the circulation and inhibits eating by acting directly on selected brain nuclei.
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Affiliation(s)
- Adele Romano
- Department of Physiology and Pharmacology “V. Erspamer”, Sapienza University of Rome, Rome, Italy
| | - Marzia Friuli
- Department of Physiology and Pharmacology “V. Erspamer”, Sapienza University of Rome, Rome, Italy
| | - Barbara Eramo
- Department of Physiology and Pharmacology “V. Erspamer”, Sapienza University of Rome, Rome, Italy
| | - Cristina Anna Gallelli
- Department of Physiology and Pharmacology “V. Erspamer”, Sapienza University of Rome, Rome, Italy
| | - Justyna Barbara Koczwara
- Department of Physiology and Pharmacology “V. Erspamer”, Sapienza University of Rome, Rome, Italy
| | | | - Adrien Paquot
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, UCLouvain, Brussels, Belgium
| | - Myrtha Arnold
- Physiology and Behavior Laboratory, ETH Zurich, Zurich, Switzerland
| | | | - Giulio G. Muccioli
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, UCLouvain, Brussels, Belgium
| | - Thomas Alexander Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Silvana Gaetani
- Department of Physiology and Pharmacology “V. Erspamer”, Sapienza University of Rome, Rome, Italy
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3
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Guerrero-Hreins E, Foldi CJ, Oldfield BJ, Stefanidis A, Sumithran P, Brown RM. Gut-brain mechanisms underlying changes in disordered eating behaviour after bariatric surgery: a review. Rev Endocr Metab Disord 2022; 23:733-751. [PMID: 34851508 DOI: 10.1007/s11154-021-09696-4] [Citation(s) in RCA: 2] [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] [Accepted: 11/12/2021] [Indexed: 02/07/2023]
Abstract
Bariatric surgery results in long-term weight loss and an improved metabolic phenotype due to changes in the gut-brain axis regulating appetite and glycaemia. Neuroendocrine alterations associated with bariatric surgery may also influence hedonic aspects of eating by inducing changes in taste preferences and central reward reactivity towards palatable food. However, the impact of bariatric surgery on disordered eating behaviours (e.g.: binge eating, loss-of-control eating, emotional eating and 'addictive eating'), which are commonly present in people with obesity are not well understood. Increasing evidence suggests gut-derived signals, such as appetitive hormones, bile acid profiles, microbiota concentrations and associated neuromodulatory metabolites, can influence pathways in the brain implicated in food intake, including brain areas involved in sensorimotor, reward-motivational, emotional-arousal and executive control components of food intake. As disordered eating prevalence is a key mediator of weight-loss success and patient well-being after bariatric surgery, understanding how changes in the gut-brain axis contribute to disordered eating incidence and severity after bariatric surgery is crucial to better improve treatment outcomes in people with obesity.
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Affiliation(s)
- Eva Guerrero-Hreins
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, Melbourne, Australia
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia
| | - Claire J Foldi
- Department of Physiology, Monash University, Clayton, Melbourne, Australia
- Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Australia
| | - Brian J Oldfield
- Department of Physiology, Monash University, Clayton, Melbourne, Australia
- Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Australia
| | - Aneta Stefanidis
- Department of Physiology, Monash University, Clayton, Melbourne, Australia
- Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Australia
| | - Priya Sumithran
- Department of Medicine (St Vincent's), University of Melbourne, Melbourne, Australia
- Department of Endocrinology, Austin Health, Melbourne, Australia
| | - Robyn M Brown
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, Melbourne, Australia.
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia.
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4
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Berland C, Small DM, Luquet S, Gangarossa G. Dietary lipids as regulators of reward processes: multimodal integration matters. Trends Endocrinol Metab 2021; 32:693-705. [PMID: 34148784 DOI: 10.1016/j.tem.2021.05.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/08/2021] [Accepted: 05/24/2021] [Indexed: 02/03/2023]
Abstract
The abundance of energy-dense and palatable diets in the modern food environment tightly contributes to the obesity pandemic. The reward circuit participates to the regulation of body homeostasis by integrating energy-related signals with neural substrates encoding cognitive and motivational components of feeding behaviors. Obesity and lipid-rich diets alter dopamine (DA) transmission leading to reward dysfunctions and food overconsumption. Recent reports indicate that dietary lipids can act, directly and indirectly, as functional modulators of the DA circuit. This raises the possibility that nutritional or genetic conditions affecting 'lipid sensing' mechanisms might lead to maladaptations of the DA system. Here, we discuss the most recent findings connecting dietary lipid sensing with DA signaling and its multimodal influence on circuits regulating food-reward processes.
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Affiliation(s)
- Chloé Berland
- Université de Paris, BFA, UMR 8251, CNRS, F-75013 Paris, France; Department of Medicine, The Naomi Berrie Diabetes Center, Columbia University, New York, NY 10032, USA
| | - Dana M Small
- Department of Psychiatry, and the Modern Diet and Physiology Research Center, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Serge Luquet
- Université de Paris, BFA, UMR 8251, CNRS, F-75013 Paris, France.
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5
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Tutunchi H, Saghafi-Asl M, Ostadrahimi A. A systematic review of the effects of oleoylethanolamide, a high-affinity endogenous ligand of PPAR-α, on the management and prevention of obesity. Clin Exp Pharmacol Physiol 2020; 47:543-552. [PMID: 31868943 DOI: 10.1111/1440-1681.13238] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 11/23/2019] [Accepted: 12/17/2019] [Indexed: 02/06/2023]
Abstract
Along with an increase in overweight and obesity among all age groups, the development of efficacious and safe anti-obesity strategies for patients, as well as health systems, is critical. Oleoylethanolamide (OEA), a high-affinity endogenous ligand of nuclear receptor peroxisome proliferator-activated receptor alpha (PPAR-α), plays important physiological and metabolic actions. OEA is derived from oleic acid, a monounsaturated fatty acid, which has beneficial effects on body composition and regional fat distribution. The role of OEA in the modulation of food consumption and weight management makes it an attractive molecule requiring further exploration in obesogenic environments. This systematic review was conducted to assess the effects of OEA on the obesity management, with emphasizing on its physiological roles and possible mechanisms of action in energy homeostasis. We searched PubMed/Medline, Google Scholar, ScienceDirect, Scopus, ProQuest, and EMBASE up until September 2019. Out of 712 records screened, 30 articles met the study criteria. The evidence reviewed here indicates that OEA, an endocannabinoid-like compound, leads to satiation or meal termination through PPAR-α activation and fatty acid translocase (FAT)/CD36. Additionally, the lipid-amide OEA stimulates fatty acid uptake, lipolysis, and beta-oxidation, and also promotes food intake control. OEA also exerts satiety-inducing effects by activating the hedonic dopamine pathways and increasing homeostatic oxytocin and brain histamine. In conclusion, OEA may be a key component of the physiological system involved in the regulation of dietary fat consumption and energy homeostasis; therefore, it is suggested as a possible therapeutic agent for the management of obesity.
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Affiliation(s)
- Helda Tutunchi
- Student Research Committee, Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Maryam Saghafi-Asl
- Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Ostadrahimi
- Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
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6
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Le Foll C. Hypothalamic Fatty Acids and Ketone Bodies Sensing and Role of FAT/CD36 in the Regulation of Food Intake. Front Physiol 2019; 10:1036. [PMID: 31474875 PMCID: PMC6702519 DOI: 10.3389/fphys.2019.01036] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/29/2019] [Indexed: 12/19/2022] Open
Abstract
The obesity and type-2 diabetes epidemic is escalating and represents one of the costliest biomedical challenges confronting modern society. Moreover, the increasing consumption of high fat food is often correlated with an increase in body mass index. In people predisposed to be obese or already obese, the impaired ability of the brain to monitor and respond to alterations in fatty acid (FA) metabolism is increasingly recognized as playing a role in the pathophysiological development of these disorders. The brain senses and regulates metabolism using highly specialized nutrient-sensing neurons located mainly in the hypothalamus. The same neurons are able to detect variation in the extracellular levels of glucose, FA and ketone bodies as a way to monitor nutrient availability and to alter its own activity. In addition, glial cells such as astrocytes create major connections to neurons and form a tight relationship to closely regulate nutrient uptake and metabolism. This review will examine the different pathways by which neurons are able to detect free fatty acids (FFA) to alter its activity and how high fat diet (HFD)-astrocytes induced ketone bodies production interplays with neuronal FA sensing. The role of HFD-induced inflammation and how FA modulate the reward system will also be investigated here.
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Affiliation(s)
- Christelle Le Foll
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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7
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Tutunchi H, Ostadrahimi A, Saghafi-Asl M, Maleki V. The effects of oleoylethanolamide, an endogenous PPAR-α agonist, on risk factors for NAFLD: A systematic review. Obes Rev 2019; 20:1057-1069. [PMID: 31111657 DOI: 10.1111/obr.12853] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/04/2019] [Accepted: 03/04/2019] [Indexed: 12/15/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease. Recently, some novel compounds have been investigated for the prevention and treatment of NAFLD. Oleoylethanolamide (OEA), an endogenous PPAR-α agonist, has exhibited a plethora of pharmacological properties for the treatment of obesity and other obesity-associated metabolic complications. This systematic review was performed with a focus on the effects of OEA on the risk factors for NAFLD. PubMed, Scopus, Embase, ProQuest, and Google Scholar databases were searched up to December 2018 using relevant keywords. All articles written in English evaluating the effects of OEA on the risk factors for NAFLD were eligible for the review. The evidence reviewed in this article illustrates that OEA regulates multiple biological processes associated with NAFLD, including lipid metabolism, inflammation, oxidative stress, and energy homeostasis through different mechanisms. In summary, many beneficial effects of OEA have led to the understanding that OEA may be an effective therapeutic strategy for the management of NAFLD. Although a wide range of studies have demonstrated the most useful effects of OEA on NAFLD and the associated risk factors, further clinical trials, from both in vivo studies and in vitro experiments, are warranted to verify these outcomes.
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Affiliation(s)
- Helda Tutunchi
- Student Research Committee, Nutrition Research Center, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.,Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Ostadrahimi
- Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Maryam Saghafi-Asl
- Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Vahid Maleki
- Student Research Committee, Nutrition Research Center, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.,Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
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8
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Klarer M, Weber-Stadlbauer U, Arnold M, Langhans W, Meyer U. Abdominal vagal deafferentation alters affective behaviors in rats. J Affect Disord 2019; 252:404-412. [PMID: 31003109 DOI: 10.1016/j.jad.2019.04.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 02/19/2019] [Accepted: 04/06/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND There is growing evidence for a role of abnormal gut-brain signaling in disorders involving altered mood and affect, including depression. Studies using vagus nerve stimulation (VNS) suggest that the disruption of vagal afferent signaling may contribute to these abnormalities. To test this hypothesis, we used a rat model of subdiaphragmatic vagal deafferentation (SDA), the most complete and selective vagal deafferentation method existing to date, to study the consequences of complete disconnection of abdominal vagal afferents on affective behaviors. METHODS SDA- and Sham-operated male rats were subjected to several tests that are commonly used in preclinical rodent models to assess the presence of anhedonic behavior, namely the novel object-induced exploration test, the novelty-suppressed eating test, and the sucrose preference test. In addition, we compared SDA and Sham rats in a social interaction test and the forced swim test to assess sociability and behavioral despair, respectively. RESULTS Compared to Sham controls, SDA rats consistently displayed signs of anhedonic behavior in all test settings used. SDA rats also showed increased immobility and reduced swimming in the forced swim test, whereas they did not differ from Sham controls with regards to social approach behavior. LIMITATIONS This study was conducted in male rats only. Hence, possible sex-specific effects of SDA on affective behaviors remained unexamined. CONCLUSIONS Our findings demonstrate that hedonic behavior and behavioral despair are subject to visceral modulation through abdominal vagal afferents. These data are compatible with preclinical models and clinical trials showing beneficial effects of VNS on depression-like and affective behaviors.
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Affiliation(s)
- Melanie Klarer
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland; Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland.
| | - Ulrike Weber-Stadlbauer
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
| | - Myrtha Arnold
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Urs Meyer
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich and ETH Zurich, Switzerland
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9
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Langhans W. Serendipity and spontaneity - Critical components in 40 years of academia. Physiol Behav 2019; 204:76-85. [PMID: 30753847 DOI: 10.1016/j.physbeh.2019.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 02/08/2019] [Indexed: 10/27/2022]
Abstract
I was flattered and felt tremendously honored to receive the 2018 Distinguished Career Award (DCA) from SSIB, the society that I always considered my scientific home, my family. Preparing the award lecture, I reflected about defining features of my career. This paper summarizes this very personal retrospective. As you will read, serendipity and more or less spontaneous decisions; i.e., some luck to be in the right place at the right time, and spontaneity to grab an opportunity when it presented itself, played a major role, and not necessarily a thorough analysis of my life situation at various junctions of my career path. Luck also often had the name of a fantastic tutor or mentor, or came in the form of enlightening discussions with a friend. Science is teamwork, which emphasizes how important collaborators, post-docs, students and technicians are. Although deep thinking was not necessarily crucial for my career path, a thorough examination is of course necessary when analyzing data, which were often most important when they did not confirm my hypothesis. Science is also hard work considering how much time one spends, but it never seemed like work to me because I had always this desire to find out how things in the organism work, and I always felt privileged to be able to pursue my "hobby" and even get a decent pay for it. In short, being a scientist is probably one of the most rewarding professional activities that life can offer.
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Affiliation(s)
- Wolfgang Langhans
- Physiology and Behavior Laboratory, Department of Health Sciences and Technology, ETH Zurich, Schorenstr. 16, 8603 Schwerzenbach, Switzerland.
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10
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Fedele S, Arnold M, Krieger JP, Wolfstädter B, Meyer U, Langhans W, Mansouri A. Oleoylethanolamide-induced anorexia in rats is associated with locomotor impairment. Physiol Rep 2019; 6. [PMID: 29388342 PMCID: PMC5817840 DOI: 10.14814/phy2.13517] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 11/01/2017] [Indexed: 11/24/2022] Open
Abstract
The endogenous peroxisome proliferator‐activated receptor alpha (PPAR‐α) agonist Oleoylethanolamide (OEA) inhibits eating in rodents, mainly by delaying the onset of meals. The underlying mechanisms of OEA‐induced anorexia, however, remain unclear. Animals treated with high OEA doses were shown to display signs of discomfort and impaired locomotion. Therefore, we first examined whether the impaired locomotion may contribute to OEA's anorectic effect. Second, it is controversial whether abdominal vagal afferents are necessary for OEA's anorectic effect. Thus, we explored alternative peripheral neural pathways mediating IP OEA's anorectic effect by performing a celiac‐superior mesenteric ganglionectomy (CGX) or a subdiaphragmatic vagal deafferentation (SDA) alone or in combination. Exogenously administered OEA at a commonly used dose (10 mg/kg BW, IP) concurrently reduced food intake and compromised locomotor activity. Attempts to dissociate both phenomena using the dopamine D2/D3 receptor agonist Quinpirole (1 mg/kg BW, SC) failed because Quinpirole antagonized both, OEA‐induced locomotor impairment and delay in eating onset. CGX attenuated the prolongation of the latency to eat by IP OEA, but neither SDA nor CGX prevented IP OEA‐induced locomotor impairment. Our results indicate that IP OEA's anorectic effect may be secondary to impaired locomotion rather than due to physiological satiety. They further confirm that vagal afferents do not mediate exogenous OEA's anorectic effects, but suggest a role for spinal afferents in addition to an alternative, nonneuronal signaling route.
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Affiliation(s)
- Shahana Fedele
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Myrtha Arnold
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | | | - Bernd Wolfstädter
- Laboratorium für Organische Chemie, ETH Zurich, Zürich, Switzerland.,Laboratory of Translational Nutrition Biology, ETH Zurich, Schwerzenbach, Switzerland
| | - Urs Meyer
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - Abdelhak Mansouri
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
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11
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Chianese R, Coccurello R, Viggiano A, Scafuro M, Fiore M, Coppola G, Operto FF, Fasano S, Laye S, Pierantoni R, Meccariello R. Impact of Dietary Fats on Brain Functions. Curr Neuropharmacol 2018; 16:1059-1085. [PMID: 29046155 PMCID: PMC6120115 DOI: 10.2174/1570159x15666171017102547] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 08/24/2017] [Accepted: 10/10/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Adequate dietary intake and nutritional status have important effects on brain functions and on brain health. Energy intake and specific nutrients excess or deficiency from diet differently affect cognitive processes, emotions, behaviour, neuroendocrine functions and synaptic plasticity with possible protective or detrimental effects on neuronal physiology. Lipids, in particular, play structural and functional roles in neurons. Here the importance of dietary fats and the need to understand the brain mechanisms activated by peripheral and central metabolic sensors. Thus, the manipulation of lifestyle factors such as dietary interventions may represent a successful therapeutic approach to maintain and preserve brain health along lifespan. METHODS This review aims at summarizing the impact of dietary fats on brain functions. RESULTS Starting from fat consumption, nutrient sensing and food-related reward, the impact of gut-brain communications will be discussed in brain health and disease. A specific focus will be on the impact of fats on the molecular pathways within the hypothalamus involved in the control of reproduction via the expression and the release of Gonadotropin-Releasing Hormone. Lastly, the effects of specific lipid classes such as polyunsaturated fatty acids and of the "fattest" of all diets, commonly known as "ketogenic diets", on brain functions will also be discussed. CONCLUSION Despite the knowledge of the molecular mechanisms is still a work in progress, the clinical relevance of the manipulation of dietary fats is well acknowledged and such manipulations are in fact currently in use for the treatment of brain diseases.
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Affiliation(s)
- Rosanna Chianese
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Roberto Coccurello
- Institute of Cell Biology and Neurobiology, National Research Council (C.N.R.), Rome, Italy.,Fondazione S. Lucia (FSL) IRCCS, Roma, Italy
| | - Andrea Viggiano
- Department of Medicine, Surgery and Scuola Medica Salernitana, University of Salerno, Baronissi, SA, Italy
| | - Marika Scafuro
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Marco Fiore
- Institute of Cell Biology and Neurobiology, National Research Council (C.N.R.), Rome, Italy.,Fondazione S. Lucia (FSL) IRCCS, Roma, Italy
| | - Giangennaro Coppola
- Department of Medicine, Surgery and Scuola Medica Salernitana, University of Salerno, Baronissi, SA, Italy.,UO Child and Adolescent Neuropsychiatry, Medical School, University of Salerno, Salerno, Italy
| | | | - Silvia Fasano
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Sophie Laye
- INRA, Bordeaux University, Nutrition and Integrative Neurobiology, UMR, Bordeaux, France
| | - Riccardo Pierantoni
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Rosaria Meccariello
- Department of Movement and Wellness Sciences, Parthenope University of Naples, Naples, Italy
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12
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Caillon A, Duszka K, Wahli W, Rohner-Jeanrenaud F, Altirriba J. The OEA effect on food intake is independent from the presence of PPARα in the intestine and the nodose ganglion, while the impact of OEA on energy expenditure requires the presence of PPARα in mice. Metabolism 2018; 87:13-17. [PMID: 29936173 DOI: 10.1016/j.metabol.2018.06.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 06/15/2018] [Accepted: 06/18/2018] [Indexed: 01/12/2023]
Abstract
BACKGROUND Oleoylethanolamide (OEA) is an endocannabinoid that controls food intake, energy expenditure and locomotor activity. Its anorexigenic effect appears to be mediated by PPARα, but the tissue where the presence of this receptor is required for OEA to inhibit feeding is unknown as yet. Previous studies point to a possible role of proximal enterocytes and neurons of the nodose ganglion. MATERIALS AND METHODS Acute intraperitoneal OEA effects on food intake, energy expenditure, respiratory exchange ratio (RER) and locomotor activity were studied in control mice (PPARα-loxP) and intestinal (Villin-Cre;PPARα-loxP) or nodose ganglion (Phox2B-Cre;PPARα-loxP) specific PPARα knockout mice placed in calorimetric cages. RESULTS OEA administration to both intestinal and nodose ganglion PPARα knockout mice decreased food intake, RER (leading to increased lipid oxidation) and locomotor activity as in control mice. However, while OEA injection acutely decreased energy expenditure in controls, this effect was not observed in mice devoid of PPARα in the intestine. CONCLUSION These results indicate that the OEA effect on food intake is independent from the presence of PPARα in the intestine and the nodose ganglion, while the impact of OEA on energy expenditure requires the presence of PPARα in the intestine.
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Affiliation(s)
- Aurélie Caillon
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, Geneva, Switzerland; Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Kalina Duszka
- Center for Integrative Genomics, University of Lausanne, Le Génopode, 1015 Lausanne, Switzerland
| | - Walter Wahli
- Center for Integrative Genomics, University of Lausanne, Le Génopode, 1015 Lausanne, Switzerland; Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 11 Mandalay Road, 308232, Singapore
| | - Françoise Rohner-Jeanrenaud
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, Geneva, Switzerland; Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Jordi Altirriba
- Laboratory of Metabolism, Department of Medicine Specialties, Faculty of Medicine, University of Geneva, Geneva, Switzerland; Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
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13
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Gallelli CA, Calcagnini S, Romano A, Koczwara JB, de Ceglia M, Dante D, Villani R, Giudetti AM, Cassano T, Gaetani S. Modulation of the Oxidative Stress and Lipid Peroxidation by Endocannabinoids and Their Lipid Analogues. Antioxidants (Basel) 2018; 7:E93. [PMID: 30021985 PMCID: PMC6070960 DOI: 10.3390/antiox7070093] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 07/10/2018] [Accepted: 07/13/2018] [Indexed: 02/06/2023] Open
Abstract
Growing evidence supports the pivotal role played by oxidative stress in tissue injury development, thus resulting in several pathologies including cardiovascular, renal, neuropsychiatric, and neurodegenerative disorders, all characterized by an altered oxidative status. Reactive oxygen and nitrogen species and lipid peroxidation-derived reactive aldehydes including acrolein, malondialdehyde, and 4-hydroxy-2-nonenal, among others, are the main responsible for cellular and tissue damages occurring in redox-dependent processes. In this scenario, a link between the endocannabinoid system (ECS) and redox homeostasis impairment appears to be crucial. Anandamide and 2-arachidonoylglycerol, the best characterized endocannabinoids, are able to modulate the activity of several antioxidant enzymes through targeting the cannabinoid receptors type 1 and 2 as well as additional receptors such as the transient receptor potential vanilloid 1, the peroxisome proliferator-activated receptor alpha, and the orphan G protein-coupled receptors 18 and 55. Moreover, the endocannabinoids lipid analogues N-acylethanolamines showed to protect cell damage and death from reactive aldehydes-induced oxidative stress by restoring the intracellular oxidants-antioxidants balance. In this review, we will provide a better understanding of the main mechanisms triggered by the cross-talk between the oxidative stress and the ECS, focusing also on the enzymatic and non-enzymatic antioxidants as scavengers of reactive aldehydes and their toxic bioactive adducts.
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Affiliation(s)
- Cristina Anna Gallelli
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
| | - Silvio Calcagnini
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
| | - Adele Romano
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
| | - Justyna Barbara Koczwara
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
| | - Marialuisa de Ceglia
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
| | - Donatella Dante
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
| | - Rosanna Villani
- C.U.R.E. University Centre for Liver Disease Research and Treatment, Department of Medical and Surgical Sciences, Institute of Internal Medicine, University of Foggia, 71122 Foggia, Italy.
| | - Anna Maria Giudetti
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Monteroni, 73100 Lecce, Italy.
| | - Tommaso Cassano
- Department of Clinical and Experimental Medicine, University of Foggia, Via Luigi Pinto, c/o Ospedali Riuniti, 71122 Foggia, Italy.
| | - Silvana Gaetani
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
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14
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Ramachandran D, Clara R, Fedele S, Michel L, Burkard J, Kaufman S, Diaz AA, Weissfeld N, De Bock K, Prip-Buus C, Langhans W, Mansouri A. Enhancing enterocyte fatty acid oxidation in mice affects glycemic control depending on dietary fat. Sci Rep 2018; 8:10818. [PMID: 30018405 PMCID: PMC6050244 DOI: 10.1038/s41598-018-29139-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 07/06/2018] [Indexed: 12/15/2022] Open
Abstract
Studies indicate that modulating enterocyte metabolism might affect whole body glucose homeostasis and the development of diet-induced obesity (DIO). We tested whether enhancing enterocyte fatty acid oxidation (FAO) could protect mice from DIO and impaired glycemic control. To this end, we used mice expressing a mutant form of carnitine palmitoyltransferase-1a (CPT1mt), insensitive to inhibition by malonyl-CoA, in their enterocytes (iCPT1mt) and fed them low-fat control diet (CD) or high-fat diet (HFD) chronically. CPT1mt expression led to an upregulation of FAO in the enterocytes. On CD, iCPT1mt mice had impaired glycemic control and showed concomitant activation of lipogenesis, glycolysis and gluconeogenesis in their enterocytes. On HFD, both iCPT1mt and control mice developed DIO, but iCPT1mt mice showed improved glycemic control and reduced visceral fat mass. Together these data indicate that modulating enterocyte metabolism in iCPT1mt mice affects glycemic control in a body weight-independent, but dietary fat-dependent manner.
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Affiliation(s)
| | - Rosmarie Clara
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Shahana Fedele
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Ladina Michel
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Johannes Burkard
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Sharon Kaufman
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | | | - Nadja Weissfeld
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Katrien De Bock
- Excercise and Health Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Carina Prip-Buus
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS, UMR, 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Abdelhak Mansouri
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland.
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15
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Hansen HS, Vana V. Non-endocannabinoid N-acylethanolamines and 2-monoacylglycerols in the intestine. Br J Pharmacol 2018; 176:1443-1454. [PMID: 29473944 DOI: 10.1111/bph.14175] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 01/23/2018] [Accepted: 02/05/2018] [Indexed: 12/11/2022] Open
Abstract
This review focuses on recent findings of the physiological and pharmacological role of non-endocannabinoid N-acylethanolamines (NAEs) and 2-monoacylglycerols (2-MAGs) in the intestine and their involvement in the gut-brain signalling. Dietary fat suppresses food intake, and much research concerns the known gut peptides, for example, glucagon-like peptide-1 (GLP-1) and cholecystokinin (CCK). NAEs and 2-MAGs represent another class of local gut signals most probably involved in the regulation of food intake. We discuss the putative biosynthetic pathways and targets of NAEs in the intestine as well as their anorectic role and changes in intestinal levels depending on the dietary status. NAEs can activate the transcription factor PPARα, but studies to evaluate the role of endogenous NAEs are generally lacking. Finally, we review the role of diet-derived 2-MAGs in the secretion of anorectic gut peptides via activation of GPR119. Both PPARα and GPR119 have potential as pharmacological targets for the treatment of obesity and the former for treatment of intestinal inflammation. LINKED ARTICLES: This article is part of a themed section on 8th European Workshop on Cannabinoid Research. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.10/issuetoc.
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Affiliation(s)
- Harald S Hansen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Vasiliki Vana
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
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16
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Sihag J, Jones PJH. Oleoylethanolamide: The role of a bioactive lipid amide in modulating eating behaviour. Obes Rev 2018; 19:178-197. [PMID: 29124885 DOI: 10.1111/obr.12630] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/19/2017] [Accepted: 09/19/2017] [Indexed: 12/13/2022]
Abstract
Fatty acid ethanolamides are lipid mediators that regulate a plethora of physiological functions. One such bioactive lipid mediator, oleoylethanolamide (OEA), is a potent agonist of the peroxisome proliferator-activated receptor-alpha (PPAR-α), which modulates increased expression of the fatty acid translocase CD36 that enables the regulation of feeding behaviour. Consumption of dietary fat rich in oleic acid activates taste receptors in the gut activating specific enzymes that lead to the formation of OEA. OEA further combines with PPAR-α to enable fat oxidation in the liver, resulting in enhanced energy production. Evidence suggests that sustained ingestion of a high-fat diet abolishes the anorexic signal of OEA. Additionally, malfunction of the enterocyte that transforms oleic acid produced during fat digestion into OEA might be responsible for reduced satiety and hyperphagia, resulting in overweight and obesity. Thus, OEA anorectic signalling may be an essential element of the physiology and metabolic system regulating dietary fat intake and obesity. The evidence reviewed in this article indicates that intake of oleic acid, and thereby the resulting OEA imparting anorexic properties, is dependent on CD36, PPAR-α, enterocyte fat sensory receptors, histamine, oxytocin and dopamine; leading to increased fat oxidation and enhanced energy expenditure to induce satiety and increase feeding latency; and that a disruption in any of these systems will cease/curb fat-induced satiety.
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Affiliation(s)
- J Sihag
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.,Richardson Centre for Functional Foods and Nutraceuticals (RCFFN), University of Manitoba, Winnipeg, Manitoba, Canada
| | - P J H Jones
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.,Richardson Centre for Functional Foods and Nutraceuticals (RCFFN), University of Manitoba, Winnipeg, Manitoba, Canada
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17
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Abdominal Vagal Afferents Modulate the Brain Transcriptome and Behaviors Relevant to Schizophrenia. J Neurosci 2018; 38:1634-1647. [PMID: 29326171 DOI: 10.1523/jneurosci.0813-17.2017] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 11/25/2017] [Accepted: 12/18/2017] [Indexed: 12/26/2022] Open
Abstract
Reduced activity of vagal efferents has long been implicated in schizophrenia and appears to be responsible for diminished parasympathetic activity and associated peripheral symptoms such as low heart rate variability and cardiovascular complications in affected individuals. In contrast, only little attention has been paid to the possibility that impaired afferent vagal signaling may be relevant for the disorder's pathophysiology as well. The present study explored this hypothesis using a model of subdiaphragmatic vagal deafferentation (SDA) in male rats. SDA represents the most complete and selective vagal deafferentation method existing to date as it leads to complete disconnection of all abdominal vagal afferents while sparing half of the abdominal vagal efferents. Using next-generation mRNA sequencing, we show that SDA leads to brain transcriptional changes in functional networks annotating with schizophrenia. We further demonstrate that SDA induces a hyperdopaminergic state, which manifests itself as increased sensitivity to acute amphetamine treatment and elevated accumbal levels of dopamine and its major metabolite, 3,4-dihydroxyphenylacetic acid. Our study also shows that SDA impairs sensorimotor gating and the attentional control of associative learning, which were assessed using the paradigms of prepulse inhibition and latent inhibition, respectively. These data provide converging evidence suggesting that the brain transcriptome, dopamine neurochemistry, and behavioral functions implicated in schizophrenia are subject to visceral modulation through abdominal vagal afferents. Our findings may encourage the further establishment and use of therapies for schizophrenia that are based on vagal interventions.SIGNIFICANCE STATEMENT The present work provides a better understanding of how disrupted vagal afferent signaling can contribute to schizophrenia-related brain and behavioral abnormalities. More specifically, it shows that subdiaphragmatic vagal deafferentation (SDA) in rats leads to (1) brain transcriptional changes in functional networks related to schizophrenia, (2) increased sensitivity to dopamine-stimulating drugs and elevated dopamine levels in the nucleus accumbens, and (3) impairments in sensorimotor gating and the attentional control of associative learning. These findings may encourage the further establishment of novel therapies for schizophrenia that are based on vagal interventions.
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18
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Ramachandran D, Clara R, Fedele S, Hu J, Lackzo E, Huang JY, Verdin E, Langhans W, Mansouri A. Intestinal SIRT3 overexpression in mice improves whole body glucose homeostasis independent of body weight. Mol Metab 2017; 6:1264-1273. [PMID: 29031725 PMCID: PMC5641632 DOI: 10.1016/j.molmet.2017.07.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 07/11/2017] [Accepted: 07/14/2017] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE Intestinal metabolism might play a greater role in regulating whole body metabolism than previously believed. We aimed to enhance enterocyte metabolism in mice and investigate if it plays a role in diet-induced obesity (DIO) and its comorbidities. METHODS Using the cre-loxP system, we overexpressed the mitochondrial NAD+ dependent protein deacetylase SIRT3 in enterocytes of mice (iSIRT3 mice). We chronically fed iSIRT3 mice and floxed-SIRT3 control (S3fl) mice a low-fat, control diet (CD) or a high-fat diet (HFD) and then phenotyped the mice. RESULTS There were no genotype differences in any of the parameters tested when the mice were fed CD. Also, iSIRT3 mice were equally susceptible to the development of DIO as S3fl mice when fed HFD. They were, however, better able than S3fl mice to regulate their blood glucose levels in response to exogenous insulin and glucose, indicating that they were protected from developing insulin resistance. This improved glucose homeostasis was accompanied by an increase in enterocyte metabolic activity and an upregulation of ketogenic gene expression in the small intestine. CONCLUSION Enhancing enterocyte oxidative metabolism can improve whole body glucose homeostasis.
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Affiliation(s)
| | - Rosmarie Clara
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Shahana Fedele
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Junmin Hu
- Functional Genomics Center Zurich (FGCZ), ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Endre Lackzo
- Functional Genomics Center Zurich (FGCZ), ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Jing-Yi Huang
- Gladstone Institute of Virology and Immunology, University of California, San Francisco, CA, USA
| | - Eric Verdin
- Gladstone Institute of Virology and Immunology, University of California, San Francisco, CA, USA
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Abdelhak Mansouri
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland.
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19
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Role of the area postrema in the hypophagic effects of oleoylethanolamide. Pharmacol Res 2017; 122:20-34. [PMID: 28535974 DOI: 10.1016/j.phrs.2017.05.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 04/10/2017] [Accepted: 05/16/2017] [Indexed: 12/25/2022]
Abstract
The satiety-promoting action of oleoylethanolamide (OEA) has been associated to the indirect activation of selected brain areas, such as the nucleus of the solitary tract (NST) in the brainstem and the tuberomammillary (TMN) and paraventricular (PVN) nuclei in the hypothalamus, where noradrenergic, histaminergic and oxytocinergic neurons play a necessary role. Visceral ascending fibers were hypothesized to mediate such effects. However, our previous findings demonstrated that the hypophagic action of peripherally administered OEA does not require intact vagal afferents and is associated to a strong activation of the area postrema (AP). Therefore, we hypothesized that OEA may exert its central effects through the direct activation of this circumventricular organ. To test this hypothesis, we subjected rats to the surgical ablation of the AP (APX rats) and evaluated the effects of OEA (10mgkg-1 i.p.) on food intake, Fos expression, hypothalamic oxytocin (OXY) immunoreactivity and on the expression of dopamine beta hydroxylase (DBH) in the brainstem and hypothalamus. We found that the AP lesion completely prevented OEA's behavioral and neurochemical effects in the brainstem and the hypothalamus. Moreover OEA increased DBH expression in AP and NST neurons of SHAM rats while the effect in the NST was absent in APX rats, thus suggesting the possible involvement of noradrenergic AP neurons. These results support the hypothesis of a necessary role of the AP in mediating OEA's central effects that sustain its pro-satiety action.
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20
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Monteiro MP, Batterham RL. The Importance of the Gastrointestinal Tract in Controlling Food Intake and Regulating Energy Balance. Gastroenterology 2017; 152:1707-1717.e2. [PMID: 28193513 DOI: 10.1053/j.gastro.2017.01.053] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 12/31/2016] [Accepted: 01/03/2017] [Indexed: 12/16/2022]
Abstract
The gastrointestinal tract, the key interface between ingested nutrients and the body, plays a critical role in regulating energy homeostasis. Gut-derived signals convey information regarding incoming nutrients to the brain, initiating changes in eating behavior and energy expenditure, to maintain energy balance. Here we review hormonal, neural, and nutrient signals emanating from the gastrointestinal tract and evidence for their role in controlling feeding behavior. Mechanistic studies that have utilized pharmacologic and/or transgenic approaches targeting an individual hormone/mediator have yielded somewhat disappointing body weight changes, often leading to the hormone/mediator in question being dismissed as a potential obesity therapy. However, the recent finding of sustained weight reduction in response to systemic administration of a long-acting analog of the gut-hormone glucagon-like peptide-1 highlights the therapeutic potential of gut-derived signals acting via nonphysiologic mechanisms. Thus, we also review therapeutics strategies being utilized or developed to leverage gastrointestinal signals in order to treat obesity.
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Affiliation(s)
- Mariana P Monteiro
- Clinical and Experimental Endocrinology, Unit for Multidisciplinary Research in Biomedicine, Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Portugal; Centre for Obesity Research, University College London, London, United Kingdom; University College London Hospitals Bariatric Centre for Weight Management and Metabolic Surgery, London, United Kingdom
| | - Rachel L Batterham
- Centre for Obesity Research, University College London, London, United Kingdom; University College London Hospitals Bariatric Centre for Weight Management and Metabolic Surgery, London, United Kingdom; National Institute of Health Research University College London Hospitals Biomedical Research Centre, London, United Kingdom.
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21
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Abstract
Obesity is a global epidemic that contributes to a number of health complications including cardiovascular disease, type 2 diabetes, cancer and neuropsychiatric disorders. Pharmacotherapeutic strategies to treat obesity are urgently needed. Research over the past two decades has increased substantially our knowledge of central and peripheral mechanisms underlying homeostatic energy balance. Homeostatic mechanisms involve multiple components including neuronal circuits, some originating in hypothalamus and brain stem, as well as peripherally-derived satiety, hunger and adiposity signals that modulate neural activity and regulate eating behavior. Dysregulation of one or more of these homeostatic components results in obesity. Coincident with obesity, reward mechanisms that regulate hedonic aspects of food intake override the homeostatic regulation of eating. In addition to functional interactions between homeostatic and reward systems in the regulation of food intake, homeostatic signals have the ability to alter vulnerability to drug abuse. Regarding the treatment of obesity, pharmacological monotherapies primarily focus on a single protein target. FDA-approved monotherapy options include phentermine (Adipex-P®), orlistat (Xenical®), lorcaserin (Belviq®) and liraglutide (Saxenda®). However, monotherapies have limited efficacy, in part due to the recruitment of alternate and counter-regulatory pathways. Consequently, a multi-target approach may provide greater benefit. Recently, two combination products have been approved by the FDA to treat obesity, including phentermine/topiramate (Qsymia®) and naltrexone/bupropion (Contrave®). The current review provides an overview of homeostatic and reward mechanisms that regulate energy balance, potential therapeutic targets for obesity and current treatment options, including some candidate therapeutics in clinical development. Finally, challenges in anti-obesity drug development are discussed.
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Affiliation(s)
- Vidya Narayanaswami
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536, USA
| | - Linda P Dwoskin
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536, USA.
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22
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Gaetani S, Romano A, Provensi G, Ricca V, Lutz T, Passani MB. Eating disorders: from bench to bedside and back. J Neurochem 2016; 139:691-699. [DOI: 10.1111/jnc.13848] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 09/12/2016] [Accepted: 09/12/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Silvana Gaetani
- Department of Physiology and Pharmacology “V. Erspamer”; Sapienza University of Rome; Rome Italy
| | - Adele Romano
- Department of Physiology and Pharmacology “V. Erspamer”; Sapienza University of Rome; Rome Italy
| | - Gustavo Provensi
- Department of Neuroscience, Psychology, Drug Discovery and Child Health (NEUROFARBA); University of Florence; Florence Italy
| | - Valdo Ricca
- Department of Neuroscience, Psychology, Drug Discovery and Child Health (NEUROFARBA); University of Florence; Florence Italy
| | - Thomas Lutz
- Institute of Veterinary Physiology; Vetsuisse Faculty University of Zurich; Zurich Switzerland
- Center of Integrative Human Physiology; University of Zurich; Zurich Switzerland
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23
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Stenblom EL, Egecioglu E, Montelius C, Ramachandran D, Bonn B, Weström B, Mansouri A, Langhans W, Erlanson-Albertsson C. Dietary thylakoids reduce visceral fat mass and increase expression of genes involved in intestinal fatty acid oxidation in high-fat fed rats. Am J Physiol Regul Integr Comp Physiol 2016; 311:R618-27. [PMID: 27488889 DOI: 10.1152/ajpregu.00212.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 07/29/2016] [Indexed: 11/22/2022]
Abstract
Thylakoids reduce body weight gain and body fat accumulation in rodents. This study investigated whether an enhanced oxidation of dietary fat-derived fatty acids in the intestine contributes to the thylakoid effects. Male Sprague-Dawley rats were fed a high-fat diet with (n = 8) or without thylakoids (n = 8) for 2 wk. Body weight, food intake, and body fat were measured, and intestinal mucosa was collected and analyzed. Quantitative real-time PCR was used to measure gene expression levels of key enzymes involved in fatty acid transport, fatty acid oxidation, and ketogenesis. Another set of thylakoid-treated (n = 10) and control rats (n = 10) went through indirect calorimetry. In the first experiment, thylakoid-treated rats (n = 8) accumulated 25% less visceral fat than controls. Furthermore, fatty acid translocase (Fat/Cd36), carnitine palmitoyltransferase 1a (Cpt1a), and mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase 2 (Hmgcs2) genes were upregulated in the jejunum of the thylakoid-treated group. In the second experiment, thylakoid-treated rats (n = 10) gained 17.5% less weight compared with controls and their respiratory quotient was lower, 0.86 compared with 0.91. Thylakoid-intake resulted in decreased food intake and did not cause steatorrhea. These results suggest that thylakoids stimulated intestinal fatty acid oxidation and ketogenesis, resulting in an increased ability of the intestine to handle dietary fat. The increased fatty acid oxidation and the resulting reduction in food intake may contribute to the reduced fat accumulation in thylakoid-treated animals.
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Affiliation(s)
- Eva-Lena Stenblom
- Department of Experimental Medical Science, Appetite Regulation Unit, Faculty of Medicine, Lund University, Lund, Sweden
| | - Emil Egecioglu
- Department of Experimental Medical Science, Appetite Regulation Unit, Faculty of Medicine, Lund University, Lund, Sweden
| | - Caroline Montelius
- Department of Experimental Medical Science, Appetite Regulation Unit, Faculty of Medicine, Lund University, Lund, Sweden
| | | | - Britta Bonn
- AstraZeneca, R&D Gothenburg, Mölndal, Sweden; and
| | - Björn Weström
- Department of Biology, Lund University, Lund, Sweden
| | - Abdelhak Mansouri
- Physiology and Behavior Laboratory, ETH Zürich, Schwerzenbach, Switzerland
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, ETH Zürich, Schwerzenbach, Switzerland
| | - Charlotte Erlanson-Albertsson
- Department of Experimental Medical Science, Appetite Regulation Unit, Faculty of Medicine, Lund University, Lund, Sweden;
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24
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The satiety factor oleoylethanolamide impacts hepatic lipid and glucose metabolism in goldfish. J Comp Physiol B 2016; 186:1009-1021. [DOI: 10.1007/s00360-016-1009-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 05/25/2016] [Accepted: 06/03/2016] [Indexed: 12/14/2022]
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25
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Le Foll C, Levin BE. Fatty acid-induced astrocyte ketone production and the control of food intake. Am J Physiol Regul Integr Comp Physiol 2016; 310:R1186-92. [PMID: 27122369 PMCID: PMC4935491 DOI: 10.1152/ajpregu.00113.2016] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 04/22/2016] [Indexed: 11/22/2022]
Abstract
Obesity and Type 2 diabetes are major worldwide public health issues today. A relationship between total fat intake and obesity has been found. In addition, the mechanisms of long-term and excessive high-fat diet (HFD) intake in the development of obesity still need to be elucidated. The ventromedial hypothalamus (VMH) is a major site involved in the regulation of glucose and energy homeostasis where "metabolic sensing neurons" integrate metabolic signals from the periphery. Among these signals, fatty acids (FA) modulate the activity of VMH neurons using the FA translocator/CD36, which plays a critical role in the regulation of energy and glucose homeostasis. During low-fat diet (LFD) intake, FA are oxidized by VMH astrocytes to fuel their ongoing metabolic needs. However, HFD intake causes VMH astrocytes to use FA to generate ketone bodies. We postulate that these astrocyte-derived ketone bodies are exported to neurons where they produce excess ATP and reactive oxygen species, which override CD36-mediated FA sensing and act as a signal to decrease short-term food intake. On a HFD, VMH astrocyte-produced ketones reduce elevated caloric intake to LFD levels after 3 days in rats genetically predisposed to resist (DR) diet-induced obesity (DIO), but not leptin-resistant DIO rats. This suggests that, while VMH ketone production on a HFD can contribute to protection from obesity, the inherent leptin resistance overrides this inhibitory action of ketone bodies on food intake. Thus, astrocytes and neurons form a tight metabolic unit that is able to monitor circulating nutrients to alter food intake and energy homeostasis.
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Affiliation(s)
- Christelle Le Foll
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland; and
| | - Barry E Levin
- Department of Neurology, Rutgers, New Jersey Medical School, Newark, New Jersey
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Romano A, Tempesta B, Provensi G, Passani MB, Gaetani S. Central mechanisms mediating the hypophagic effects of oleoylethanolamide and N-acylphosphatidylethanolamines: different lipid signals? Front Pharmacol 2015; 6:137. [PMID: 26167152 PMCID: PMC4481858 DOI: 10.3389/fphar.2015.00137] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 06/19/2015] [Indexed: 12/19/2022] Open
Abstract
The spread of “obesity epidemic” and the poor efficacy of many anti-obesity therapies in the long-term highlight the need to develop novel efficacious therapy. This necessity stimulates a large research effort to find novel mechanisms controlling feeding and energy balance. Among these mechanisms a great deal of attention has been attracted by a family of phospholipid-derived signaling molecules that play an important role in the regulation of food-intake. They include N-acylethanolamines (NAEs) and N-acylphosphatidylethanolamines (NAPEs). NAPEs have been considered for a long time simply as phospholipid precursors of the lipid mediator NAEs, but increasing body of evidence suggest a role in many physiological processes including the regulation of feeding behavior. Several observations demonstrated that among NAEs, oleoylethanolamide (OEA) acts as a satiety signal, which is generated in the intestine, upon the ingestion of fat, and signals to the central nervous system. At this level different neuronal pathways, including oxytocinergic, noradrenergic, and histaminergic neurons, seem to mediate its hypophagic action. Similarly to NAEs, NAPE (with particular reference to the N16:0 species) levels were shown to be regulated by the fed state and this finding was initially interpreted as fluctuations of NAE precursors. However, the observation that exogenously administered NAPEs are able to inhibit food intake, not only in normal rats and mice but also in mice lacking the enzyme that converts NAPEs into NAEs, supported the hypothesis of a role of NAPE in the regulation of feeding behavior. Indirect observations suggest that the hypophagic action of NAPEs might involve central mechanisms, although the molecular target remains unknown. The present paper reviews the role that OEA and NAPEs play in the mechanisms that control food intake, further supporting this group of phospholipids as optimal candidate for the development of novel anti-obesity treatments.
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Affiliation(s)
- Adele Romano
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome , Rome,Italy
| | - Bianca Tempesta
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome , Rome,Italy
| | - Gustavo Provensi
- Department of Neuroscience, Psychology, Drug Discovery and Child Health (NEUROFARBA), University of Florence , Florence, Italy
| | - Maria B Passani
- Department of Neuroscience, Psychology, Drug Discovery and Child Health (NEUROFARBA), University of Florence , Florence, Italy
| | - Silvana Gaetani
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome , Rome,Italy
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27
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Hankir MK, Ashrafian H, Hesse S, Horstmann A, Fenske WK. Distinctive striatal dopamine signaling after dieting and gastric bypass. Trends Endocrinol Metab 2015; 26:223-30. [PMID: 25887491 DOI: 10.1016/j.tem.2015.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Revised: 03/10/2015] [Accepted: 03/15/2015] [Indexed: 12/25/2022]
Abstract
Highly palatable and/or calorically dense foods, such as those rich in fat, engage the striatum to govern and set complex behaviors. Striatal dopamine signaling has been implicated in hedonic feeding and the development of obesity. Dieting and bariatric surgery have markedly different outcomes on weight loss, yet how these interventions affect central homeostatic and food reward processing remains poorly understood. Here, we propose that dieting and gastric bypass produce distinct changes in peripheral factors with known roles in regulating energy homeostasis, resulting in differential modulation of nigrostriatal and mesolimbic dopaminergic reward circuits. Enhancement of intestinal fat metabolism after gastric bypass may also modify striatal dopamine signaling contributing to its unique long-term effects on feeding behavior and body weight in obese individuals.
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Affiliation(s)
- Mohammed K Hankir
- Leipzig University Medical Center, IFB Adiposity Diseases, Leipzig, Germany
| | - Hutan Ashrafian
- Department of Surgery & Cancer, Imperial College London, London, UK.
| | - Swen Hesse
- Leipzig University Medical Center, IFB Adiposity Diseases, Leipzig, Germany; Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - Annette Horstmann
- Leipzig University Medical Center, IFB Adiposity Diseases, Leipzig, Germany; Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Wiebke K Fenske
- Leipzig University Medical Center, IFB Adiposity Diseases, Leipzig, Germany
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28
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Abstract
Fat is a vital macronutrient, and its intake is closely monitored by an array of molecular sensors distributed throughout the alimentary canal. In the mouth, dietary fat constituents such as mono- and diunsaturated fatty acids give rise to taste signals that stimulate food intake, in part by enhancing the production of lipid-derived endocannabinoid messengers in the gut. As fat-containing chyme enters the small intestine, it causes the formation of anorexic lipid mediators, such as oleoylethanolamide, which promote satiety. These anatomically and functionally distinct responses may contribute to the homeostatic control and, possibly, the pathological dysregulation of food intake.
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Affiliation(s)
| | - Daniele Piomelli
- Departments of Anatomy and Neurobiology
- Department of Pharmacology, and
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, California, USA
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Genoa, Italy
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Scheuble N, Geue T, Windhab EJ, Fischer P. Tailored Interfacial Rheology for Gastric Stable Adsorption Layers. Biomacromolecules 2014; 15:3139-45. [DOI: 10.1021/bm500767c] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- N. Scheuble
- Institute
of Food Nutrition and Health, ETH Zurich, 8092 Zurich, Switzerland
| | - T. Geue
- Laboratory
of Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - E. J. Windhab
- Institute
of Food Nutrition and Health, ETH Zurich, 8092 Zurich, Switzerland
| | - P. Fischer
- Institute
of Food Nutrition and Health, ETH Zurich, 8092 Zurich, Switzerland
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30
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Satiety factor oleoylethanolamide recruits the brain histaminergic system to inhibit food intake. Proc Natl Acad Sci U S A 2014; 111:11527-32. [PMID: 25049422 DOI: 10.1073/pnas.1322016111] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Key factors driving eating behavior are hunger and satiety, which are controlled by a complex interplay of central neurotransmitter systems and peripheral stimuli. The lipid-derived messenger oleoylethanolamide (OEA) is released by enterocytes in response to fat intake and indirectly signals satiety to hypothalamic nuclei. Brain histamine is released during the appetitive phase to provide a high level of arousal in anticipation of feeding, and mediates satiety. However, despite the possible functional overlap of satiety signals, it is not known whether histamine participates in OEA-induced hypophagia. Using different experimental settings and diets, we report that the anorexiant effect of OEA is significantly attenuated in mice deficient in the histamine-synthesizing enzyme histidine decarboxylase (HDC-KO) or acutely depleted of histamine via interocerebroventricular infusion of the HDC blocker α-fluoromethylhistidine (α-FMH). α-FMH abolished OEA-induced early occurrence of satiety onset while increasing histamine release in the CNS with an H3 receptor antagonist-increased hypophagia. OEA augmented histamine release in the cortex of fasted mice within a time window compatible to its anorexic effects. OEA also increased c-Fos expression in the oxytocin neurons of the paraventricular nuclei of WT but not HDC-KO mice. The density of c-Fos immunoreactive neurons in other brain regions that receive histaminergic innervation and participate in the expression of feeding behavior was comparable in OEA-treated WT and HDC-KO mice. Our results demonstrate that OEA requires the integrity of the brain histamine system to fully exert its hypophagic effect and that the oxytocin neuron-rich nuclei are the likely hypothalamic area where brain histamine influences the central effects of OEA.
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