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Lee TH, Cota D, Quarta C. Yin-Yang control of energy balance by lipids in the hypothalamus: The endocannabinoids vs bile acids case. Biochimie 2024; 223:188-195. [PMID: 35863558 DOI: 10.1016/j.biochi.2022.07.006] [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: 05/23/2022] [Revised: 06/22/2022] [Accepted: 07/12/2022] [Indexed: 11/02/2022]
Abstract
Obesity is a chronic and debilitating disorder that originates from alterations in energy-sensing brain circuits controlling body weight gain and food intake. The dysregulated syntheses and actions of lipid mediators in the hypothalamus induce weight gain and overfeeding, but the molecular and cellular underpinnings of these alterations remain elusive. In response to changes in the nutritional status, different lipid sensing pathways in the hypothalamus direct body energy needs in a Yin-Yang model. Endocannabinoids orchestrate the crosstalk between hypothalamic circuits and the sympathetic nervous system to promote food intake and energy accumulation during fasting, whereas bile acids act on the same top-down axis to reduce energy intake and possibly storage after the meal. In obesity, the bioavailability and downstream cellular actions of endocannabinoids and bile acids are altered in hypothalamic neurons involved in body weight and metabolic control. Thus, the onset and progression of this disease might result from an imbalance in hypothalamic sensing of multiple lipid signals, which are possibly integrated by common molecular nodes. In this viewpoint, we discuss a possible model that explains how bile acids and endocannabinoids may exert their effects on energy balance regulation via interconnected mechanisms at the level of the hypothalamic neuronal circuits. Therefore, we propose a new conceptual framework for understanding and treating central mechanisms of maladaptive lipid action in obesity.
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Affiliation(s)
- Thomas H Lee
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France
| | - Daniela Cota
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France
| | - Carmelo Quarta
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France.
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2
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Dearden L, Furigo IC, Pantaleão LC, Wong LWP, Fernandez-Twinn DS, de Almeida-Faria J, Kentistou KA, Carreira MV, Bidault G, Vidal-Puig A, Ong KK, Perry JRB, Donato J, Ozanne SE. Maternal obesity increases hypothalamic miR-505-5p expression in mouse offspring leading to altered fatty acid sensing and increased intake of high-fat food. PLoS Biol 2024; 22:e3002641. [PMID: 38833481 PMCID: PMC11149872 DOI: 10.1371/journal.pbio.3002641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 04/25/2024] [Indexed: 06/06/2024] Open
Abstract
In utero exposure to maternal obesity programs increased obesity risk. Animal models show that programmed offspring obesity is preceded by hyperphagia, but the mechanisms that mediate these changes are unknown. Using a mouse model of maternal obesity, we observed increased intake of a high-fat diet (HFD) in offspring of obese mothers that precedes the development of obesity. Through small RNA sequencing, we identified programmed overexpression of hypothalamic miR-505-5p that is established in the fetus, lasts to adulthood and is maintained in hypothalamic neural progenitor cells cultured in vitro. Metabolic hormones and long-chain fatty acids associated with obesity increase miR-505-5p expression in hypothalamic neurons in vitro. We demonstrate that targets of miR-505-5p are enriched in fatty acid metabolism pathways and overexpression of miR-505-5p decreased neuronal fatty acid metabolism in vitro. miR-505-5p targets are associated with increased BMI in human genetic studies. Intra-cerebroventricular injection of miR-505-5p in wild-type mice increased HFD intake, mimicking the phenotype observed in offspring exposed to maternal obesity. Conversely, maternal exercise intervention in an obese mouse pregnancy rescued the programmed increase of hypothalamic miR-505-5p in offspring of obese dams and reduced HFD intake to control offspring levels. This study identifies a novel mechanism by which maternal obesity programs obesity in offspring via increased intake of high-fat foods.
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Affiliation(s)
- Laura Dearden
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - Isadora C. Furigo
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, Brazil
- Centre for Health and Life Sciences, Coventry University, Coventry, United Kingdom
| | - Lucas C. Pantaleão
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - L W. P. Wong
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - Denise S. Fernandez-Twinn
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - Juliana de Almeida-Faria
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
- University of Campinas, Faculty of Medical Sciences, Department of Pharmacology, Campinas, Brazil
| | | | - Maria V. Carreira
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - Guillaume Bidault
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - Antonio Vidal-Puig
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - Ken K. Ong
- MRC Epidemiology Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - John R. B. Perry
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Epidemiology Unit, Institute of Metabolic Science, Cambridge, United Kingdom
| | - Jose Donato
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, Sao Paulo, Brazil
| | - Susan E. Ozanne
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge, United Kingdom
- MRC Metabolic Diseases Unit, Institute of Metabolic Science, Cambridge, United Kingdom
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3
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Konadu B, Cox CK, Garrett MR, Gibert Y. Excess glucose or fat differentially affects metabolism and appetite-related gene expression during zebrafish embryogenesis. iScience 2023; 26:107063. [PMID: 37534154 PMCID: PMC10391732 DOI: 10.1016/j.isci.2023.107063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 03/28/2023] [Accepted: 06/02/2023] [Indexed: 08/04/2023] Open
Abstract
Zebrafish embryos use their yolk sac reserve as the sole nutrient source during embryogenesis. The two main forms of energy fuel can be found in the form of glucose or fat. Zebrafish embryos were exposed to glucose or injected with free fatty acid/Triacylglycerol (FFA/TAG) into the yolk sac at 24 hpf. At 72 hpf, glucose exposed or FFA/TAG injected had differential effects on gene expression in embryos, with fat activating lipolysis and β-oxidation and glucose activating the insulin pathway. Bulk RNA-seq revealed that more gene expression was affected by glucose exposure compared to FFA/TAGs injection. Appetite-controlling genes were also differently affected by glucose exposure or FFA/TAG injections. Because the embryo did not yet feed itself at the time of our analysis, gene expression changes occurred in absence of actual hunger and revealed how the embryo manages its nutrient intake before active feeding.
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Affiliation(s)
- Bridget Konadu
- Department of Cell and Molecular Biology, Cancer Center and Research Institute, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Carol K. Cox
- Department of Cell and Molecular Biology, Cancer Center and Research Institute, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Michael R. Garrett
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Yann Gibert
- Department of Cell and Molecular Biology, Cancer Center and Research Institute, University of Mississippi Medical Center, Jackson, MS 39216, USA
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4
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Ruiz-Cruz M, Torres-Granados C, Tena-Sempere M, Roa J. Central and peripheral mechanisms involved in the control of GnRH neuronal function by metabolic factors. Curr Opin Pharmacol 2023; 71:102382. [PMID: 37307655 DOI: 10.1016/j.coph.2023.102382] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/21/2023] [Accepted: 04/24/2023] [Indexed: 06/14/2023]
Abstract
Gonadotropin-releasing hormone (GnRH) neurons are the final output pathway for the brain control of reproduction. The activity of this neuronal population, mainly located at the preoptic area of the hypothalamus, is controlled by a plethora of metabolic signals. However, it has been documented that most of these signal impact on GnRH neurons through indirect neuronal circuits, Kiss1, proopiomelanocortin, and neuropeptide Y/agouti-related peptide neurons being some of the most prominent mediators. In this context, compelling evidence has been gathered in recent years on the role of a large range of neuropeptides and energy sensors in the regulation of GnRH neuronal activity through both direct and indirect mechanisms. The present review summarizes some of the most prominent recent advances in our understanding of the peripheral factors and central mechanisms involved in the metabolic control of GnRH neurons.
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Affiliation(s)
- Miguel Ruiz-Cruz
- Instituto Maimónides de Investigación Biomédica de Córdoba, Department of Cell Biology, Physiology and Immunology, University of Córdoba; Hospital Universitario Reina Sofia (IMIBIC/HURS), 14004 Córdoba, Spain
| | - Carmen Torres-Granados
- Instituto Maimónides de Investigación Biomédica de Córdoba, Department of Cell Biology, Physiology and Immunology, University of Córdoba; Hospital Universitario Reina Sofia (IMIBIC/HURS), 14004 Córdoba, Spain
| | - Manuel Tena-Sempere
- Instituto Maimónides de Investigación Biomédica de Córdoba, Department of Cell Biology, Physiology and Immunology, University of Córdoba; Hospital Universitario Reina Sofia (IMIBIC/HURS), 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Juan Roa
- Instituto Maimónides de Investigación Biomédica de Córdoba, Department of Cell Biology, Physiology and Immunology, University of Córdoba; Hospital Universitario Reina Sofia (IMIBIC/HURS), 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain.
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Wu W, Sun B, He H, Cao X, Gao J. scd knockout activates β-oxidation of fatty acids via accumulating stearic acid (18:0) and induces anorexia in zebrafish. Gene 2023; 871:147431. [PMID: 37068693 DOI: 10.1016/j.gene.2023.147431] [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: 11/10/2022] [Revised: 04/02/2023] [Accepted: 04/11/2023] [Indexed: 04/19/2023]
Abstract
Stearoyl-CoA desaturase (scd) is the rate-limiting enzyme for the biosynthesis of monounsaturated fatty acids (MUFA), and it plays a critical role in regulating hepatic lipogenesis and lipid oxidation. However, its role in teleosts remains unclear. In this study, we generated scd knockout zebrafish (scd-/-) to explore the role of Scd in regulating growth and metabolism in teleosts. The results showed that scd knockout reduces hepatic lipid deposition by down-regulating the expression of lipogenesis-related genes and up-regulating the expression of lipolysis-related genes. In addition, the knockout of scd suppressed food intake and reduced body weight. Further analysis confirmed that scd knockout suppressed the feeding behavior by decreasing expression of orexigenic peptide genes and increasing expression of anorexigenic peptide genes. The high-level stearic acid (18:0) feeding experiment results showed that the accumulation of 18:0 inhibited feeding behavior, reduced food intake, decreased body weight, and increased lipid β-oxidation, which was essentially consistent with the phenotypes of scd deficiency. Taken together, our results indicate that the knockout of scd inhibited the food intake through the accumulation of 18:0. This study preliminarily reveals the role of Scd in regulating food intake of teleosts, which provides theoretical basis for the functional study of Scd.
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Affiliation(s)
- Wenpeng Wu
- College of Fisheries, Engineering Research Center of Green development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China
| | - Bing Sun
- College of Fisheries, Engineering Research Center of Green development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China
| | - Houxiong He
- College of Fisheries, Engineering Research Center of Green development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiaojuan Cao
- College of Fisheries, Engineering Research Center of Green development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Jian Gao
- College of Fisheries, Engineering Research Center of Green development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China.
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Central Regulation of Brown Fat Thermogenesis in Response to Saturated or Unsaturated Long-Chain Fatty Acids. Int J Mol Sci 2023; 24:ijms24021697. [PMID: 36675212 PMCID: PMC9866012 DOI: 10.3390/ijms24021697] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/17/2023] Open
Abstract
Sensing of long-chain fatty acids (LCFA) in the hypothalamus modulates energy balance, and its disruption leads to obesity. To date, the effects of saturated or unsaturated LCFA on hypothalamic-brown adipose tissue (BAT) axis and the underlying mechanisms have remained largely unclear. Our aim was to characterize the main molecular pathways involved in the hypothalamic regulation of BAT thermogenesis in response to LCFA with different lengths and degrees of saturation. One-week administration of high-fat diet enriched in monounsaturated FA led to higher BAT thermogenesis compared to a saturated FA-enriched diet. Intracerebroventricular infusion of oleic and linoleic acids upregulated thermogenesis markers and temperature in brown fat of mice, and triggered neuronal activation of paraventricular (PaV), ventromedial (VMH) and arcuate (ARC) hypothalamic nuclei, which was not found with saturated FAs. The neuron-specific protein carnitine palmitoyltransferase 1-C (CPT1C) was a crucial effector of oleic acid since the FA action was blunted in CPT1C-KO mice. Moreover, changes in the AMPK/ACC/malonyl-CoA pathway and fatty acid synthase expression were evoked by oleic acid. Altogether, central infusion of unsaturated but not saturated LCFA increases BAT thermogenesis through CPT1C-mediated sensing of FA metabolism shift, which in turn drive melanocortin system activation. These findings add new insight into neuronal circuitries activated by LCFA to drive thermogenesis.
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Puente-Ruiz SC, Jais A. Reciprocal signaling between adipose tissue depots and the central nervous system. Front Cell Dev Biol 2022; 10:979251. [PMID: 36200038 PMCID: PMC9529070 DOI: 10.3389/fcell.2022.979251] [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: 06/27/2022] [Accepted: 08/24/2022] [Indexed: 11/13/2022] Open
Abstract
In humans, various dietary and social factors led to the development of increased brain sizes alongside large adipose tissue stores. Complex reciprocal signaling mechanisms allow for a fine-tuned interaction between the two organs to regulate energy homeostasis of the organism. As an endocrine organ, adipose tissue secretes various hormones, cytokines, and metabolites that signal energy availability to the central nervous system (CNS). Vice versa, the CNS is a critical regulator of adipose tissue function through neural networks that integrate information from the periphery and regulate sympathetic nerve outflow. This review discusses the various reciprocal signaling mechanisms in the CNS and adipose tissue to maintain organismal energy homeostasis. We are focusing on the integration of afferent signals from the periphery in neuronal populations of the mediobasal hypothalamus as well as the efferent signals from the CNS to adipose tissue and its implications for adipose tissue function. Furthermore, we are discussing central mechanisms that fine-tune the immune system in adipose tissue depots and contribute to organ homeostasis. Elucidating this complex signaling network that integrates peripheral signals to generate physiological outputs to maintain the optimal energy balance of the organism is crucial for understanding the pathophysiology of obesity and metabolic diseases such as type 2 diabetes.
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8
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Dos Santos Neves L, Oliveira RKG, Dos Santos LS, Ribeiro IO, Medeiros JMB, de Matos RJB. Modulation of hypothalamic AMPK and hypothalamic neuropeptides in the control of eating behavior: A systematic review. Life Sci 2022; 309:120947. [PMID: 36096244 DOI: 10.1016/j.lfs.2022.120947] [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: 06/27/2022] [Revised: 09/03/2022] [Accepted: 09/07/2022] [Indexed: 12/09/2022]
Abstract
Eating behavior is regulated by central and peripheral signals, which interact to modulate the response to nutrient intake. Central control is mediated by the hypothalamus through neuropeptides that activate the orexigenic and anorexigenic pathways. Energy homeostasis depends on the efficiency of these regulatory mechanisms. This neuroendocrine regulation of hunger and appetite can be modulated by nutritional sensors such as adenosine monophosphate-activated protein kinase (AMPK). Thus, this systematic review discusses the literature on correlations between AMPK and hypothalamic neuropeptides regarding control of eating behavior. Lilacs, PubMed/Medline, ScienceDirect, and Web of Science were searched for articles published from 2009 to 2021 containing combinations of the following descriptors: "eating behavior," "hypothalamus," "neuropeptide," and "AMPK." Of the 1330 articles found initially, 27 were selected after application of the inclusion and exclusion criteria. Of the selected articles, 15 reported decreased AMPK activity, due to interventions using angiotensin II infusion, fructose, glucose, cholecystokinin, leptin, or lipopolysaccharide (LPS) injection; dietary control through a low-protein diet or a high-fat diet (60 % fat); induction of hyperthyroidism; or injection of AMPK inhibitors. Seven studies showed a decrease in neuropeptide Y (NPY) through CV4 AICAR administration; fructose, glucose, leptin, or angiotensin II injections; or infusion of LPS from Escherichia coli and liver kinase B1 (LKB1) overexpression. Eleven studies reported a decrease in food consumption due to a decrease in AMPK activity and/or hypothalamic neuropeptides such as NPY. The results indicate that there is a relationship between AMPK and the control of eating behavior: a decrease in AMPK activity due to a dietary or non-dietary stimulus is associated with a consequent decrease in food intake. Furthermore, AMPK activity can be modulated by glucose, thyroid hormones, estradiol, leptin, and ghrelin.
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Affiliation(s)
- Letycia Dos Santos Neves
- Vitoria Academic Center, Federal University of Pernambuco, Rua do Alto do Reservoir, S/N, Bela Vista, CEP 55608-680 Vitória de Santo Antão, PE, Brazil
| | - Renata Kelly Gomes Oliveira
- Vitoria Academic Center, Federal University of Pernambuco, Rua do Alto do Reservoir, S/N, Bela Vista, CEP 55608-680 Vitória de Santo Antão, PE, Brazil
| | - Lucimeire Santana Dos Santos
- Federal University of Bahia, School of Nutrition, Rua Basilio da Gama, s/n, Campus Canela, CEP: 40.110-907 Salvador, BA, Brazil
| | - Ingrid Oliveira Ribeiro
- Federal University of Bahia, School of Nutrition, Rua Basilio da Gama, s/n, Campus Canela, CEP: 40.110-907 Salvador, BA, Brazil
| | - Jairza Maria Barreto Medeiros
- Federal University of Bahia, School of Nutrition, Rua Basilio da Gama, s/n, Campus Canela, CEP: 40.110-907 Salvador, BA, Brazil
| | - Rhowena Jane Barbosa de Matos
- Health Sciences Center, Federal University of Recôncavo of Bahia, Avenida Carlos Amaral, 1015, Cajueiro, CEP 44574-490 Santo Antônio de Jesus, BA, Brazil.
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Yerlikaya S, Djamgoz MB. Oleamide, a Sleep-Inducing Compound: Effects on Ion Channels and Cancer. Bioelectricity 2022. [DOI: 10.1089/bioe.2022.0010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Serife Yerlikaya
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, Turkey
| | - Mustafa B.A. Djamgoz
- Department of Life Sciences, Imperial College London, London, United Kingdom
- Biotechnology Research Center, Cyprus International University, Haspolat, Nicosia, TRNC, Mersin 10, Turkey
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10
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He Z, Lieu L, Dong Y, Afrin S, Chau D, Kabahizi A, Wallace B, Cao J, Hwang ES, Yao T, Huang Y, Okolo J, Cheng B, Gao Y, Hu L, Williams KW. PERK in POMC neurons connects celastrol with metabolism. JCI Insight 2021; 6:145306. [PMID: 34549728 PMCID: PMC8492333 DOI: 10.1172/jci.insight.145306] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 07/28/2021] [Indexed: 01/02/2023] Open
Abstract
ER stress and activation of the unfolded protein response in the periphery as well as the central nervous system have been linked to various metabolic abnormalities. Chemically lowering protein kinase R–like ER kinase (PERK) activity within the hypothalamus leads to decreased food intake and body weight. However, the cell populations required in this response remain undefined. In the current study, we investigated the effects of proopiomelanocortin-specific (POMC-specific) PERK deficiency on energy balance and glucose metabolism. Male mice deficient for PERK in POMC neurons exhibited improvements in energy balance on a high-fat diet, showing decreased food intake and body weight, independent of changes in glucose and insulin tolerances. The plant-based inhibitor of PERK, celastrol, increases leptin sensitivity, resulting in decreased food intake and body weight in a murine model of diet-induced obesity (DIO). Our data extend these observations by demonstrating that celastrol-induced improvements in leptin sensitivity and energy balance were attenuated in mice with PERK deficiency in POMC neurons. Altogether, these data suggest that POMC-specific PERK deficiency in male mice confers protection against DIO, possibly providing a new therapeutic target for the treatment of diabetes and metabolic syndrome.
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Affiliation(s)
- Zhenyan He
- Department of Neurosurgery, Affiliated Tumor Hospital of Zhengzhou University, Zhengzhou, Henan, China.,Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Linh Lieu
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Yanbin Dong
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA.,Institute of Gastroenterology and.,Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Sadia Afrin
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Dominic Chau
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Anita Kabahizi
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Briana Wallace
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Jianhong Cao
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Eun-Sang Hwang
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Ting Yao
- Division of Pediatric Endocrinology, Department of Pediatrics, UCLA Children's Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Yiru Huang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Jennifer Okolo
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Bo Cheng
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Yong Gao
- Laboratory Department, Affiliated Hospital of Binzhou Medical College, Shandong, China
| | - Ling Hu
- Institute of Gastroenterology and.,Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Kevin W Williams
- Center for Hypothalamic Research, Department of Internal Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
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11
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Ruigrok SR, Stöberl N, Yam KY, de Lucia C, Lucassen PJ, Thuret S, Korosi A. Modulation of the Hypothalamic Nutrient Sensing Pathways by Sex and Early-Life Stress. Front Neurosci 2021; 15:695367. [PMID: 34366778 PMCID: PMC8342927 DOI: 10.3389/fnins.2021.695367] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 06/28/2021] [Indexed: 12/14/2022] Open
Abstract
There are sex differences in metabolic disease risk, and early-life stress (ES) increases the risk to develop such diseases, potentially in a sex-specific manner. It remains to be understood, however, how sex and ES affect such metabolic vulnerability. The hypothalamus regulates food intake and energy expenditure by sensing the organism's energy state via metabolic hormones (leptin, insulin, ghrelin) and nutrients (glucose, fatty acids). Here, we investigated if and how sex and ES alter hypothalamic nutrient sensing short and long-term. ES was induced in mice by limiting the bedding and nesting material from postnatal day (P)2-P9, and the expression of genes critical for hypothalamic nutrient sensing were studied in male and female offspring, both at P9 and in adulthood (P180). At P9, we observed a sex difference in both Ppargc1a and Lepr expression, while the latter was also increased in ES-exposed animals relative to controls. In adulthood, we found sex differences in Acacb, Agrp, and Npy expression, whereas ES did not affect the expression of genes involved in hypothalamic nutrient sensing. Thus, we observe a pervasive sex difference in nutrient sensing pathways and a targeted modulation of this pathway by ES early in life. Future research is needed to address if the modulation of these pathways by sex and ES is involved in the differential vulnerability to metabolic diseases.
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Affiliation(s)
- Silvie R. Ruigrok
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Nina Stöberl
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Kit-Yi Yam
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Chiara de Lucia
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Paul J. Lucassen
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Sandrine Thuret
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Aniko Korosi
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
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Sánchez-Alegría K, Bastián-Eugenio CE, Vaca L, Arias C. Palmitic acid induces insulin resistance by a mechanism associated with energy metabolism and calcium entry in neuronal cells. FASEB J 2021; 35:e21712. [PMID: 34110637 DOI: 10.1096/fj.202100243r] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/27/2021] [Accepted: 05/17/2021] [Indexed: 01/05/2023]
Abstract
Palmitic acid (PA) is a saturated fatty acid whose high consumption has been largely associated with the development of different metabolic alterations, such as insulin resistance, metabolic syndrome, and type 2 diabetes. Particularly in the brain, insulin signaling disruption has been linked to cognitive decline and is considered a risk factor for Alzheimer's disease. Cumulative evidence has demonstrated the participation of PA in the molecular cascade underlying cellular insulin resistance in peripheral tissues, but its role in the development of neuronal insulin resistance and the mechanisms involved are not fully understood. It has generally been accepted that the brain does not utilize fatty acids as a primary energy source, but recent evidence shows that neurons possess the machinery for fatty acid β-oxidation. However, it is still unclear under what conditions neurons use fatty acids as energy substrates and the implications of their oxidative metabolism in modifying insulin-stimulated effects. In the present work, we have found that neurons differentiated from human neuroblastoma MSN exposed to high but nontoxic concentrations of PA generate ATP through mitochondrial metabolism, which is associated with an increase in the cytosolic Ca2+ and diminished insulin signaling in neurons. These findings reveal a novel mechanism by which saturated fatty acids produce Ca2+ entry and insulin resistance that may play a causal role in increasing neuronal vulnerability associated with metabolic diseases.
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Affiliation(s)
- Karina Sánchez-Alegría
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Carlos Ernesto Bastián-Eugenio
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Luis Vaca
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Clorinda Arias
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
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13
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Neural mechanisms underlying the role of fructose in overfeeding. Neurosci Biobehav Rev 2021; 128:346-357. [PMID: 34182019 DOI: 10.1016/j.neubiorev.2021.06.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 06/16/2021] [Accepted: 06/23/2021] [Indexed: 10/21/2022]
Abstract
Fructose consumption has been linked with metabolic syndrome and obesity. Fructose-based sweeteners like high fructose corn syrup taste sweeter, improve food palatability, and are increasingly prevalent in our diet. The increase in fructose consumption precedes the rise in obesity and is a contributing driver to the obesity epidemic worldwide. The role of dietary fructose in obesity can be multifactorial by promoting visceral adiposity, hypertension, and insulin resistance. Interestingly, one emergent finding from human and animal studies is that dietary fructose promotes overfeeding. As the brain is a critical regulator of food intake, we reviewed the evidence that fructose can act in the brain and elucidated the major brain systems underlying fructose-induced overfeeding. We found that fructose acts on multiple interdependent brain systems to increase orexigenic drive and the incentive salience of food while decreasing the latency between food bouts and reducing cognitive control to disinhibit feeding. We concluded that the collective actions of fructose may promote feeding behavior by producing a hunger-like state in the brain.
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14
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Flores-León M, Alcaraz N, Pérez-Domínguez M, Torres-Arciga K, Rebollar-Vega R, De la Rosa-Velázquez IA, Arriaga-Canon C, Herrera LA, Arias C, González-Barrios R. Transcriptional Profiles Reveal Deregulation of Lipid Metabolism and Inflammatory Pathways in Neurons Exposed to Palmitic Acid. Mol Neurobiol 2021; 58:4639-4651. [PMID: 34155583 DOI: 10.1007/s12035-021-02434-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 05/18/2021] [Indexed: 12/13/2022]
Abstract
The effects of the consumption of high-fat diets (HFD) have been studied to unravel the molecular pathways they are altering in order to understand the link between increased caloric intake, metabolic diseases, and the risk of cognitive dysfunction. The saturated fatty acid, palmitic acid (PA), is the main component of HFD and it has been found increased in the circulation of obese and diabetic people. In the central nervous system, PA has been associated with inflammatory responses in astrocytes, but the effects on neurons exposed to it have not been largely investigated. Given that PA affects a variety of metabolic pathways, we aimed to analyze the transcriptomic profile activated by this fatty acid to shed light on the mechanisms of neuronal dysfunction. In the current study, we profiled the transcriptome response after PA exposition at non-toxic doses in primary hippocampal neurons. Gene ontology and Reactome pathway analysis revealed a pattern of gene expression which is associated with inflammatory pathways, and importantly, with the activation of lipid metabolism that is considered not very active in neurons. Validation by quantitative RT-PCR (qRT-PCR) of Hmgcs2, Angptl4, Ugt8, and Rnf145 support the results obtained by RNAseq. Overall, these findings suggest that neurons are able to respond to saturated fatty acids changing the expression pattern of genes associated with inflammatory response and lipid utilization that may be involved in the neuronal damage associated with metabolic diseases.
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Affiliation(s)
- M Flores-León
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - N Alcaraz
- The Bioinformatics Centre. Department of Biology, University of Copenhagen, Ole Maaloes Vej 5, DK-2200, Copenhagen N, Denmark
- Instituto Nacional de Medicina Genómica, Periférico Sur 4809, Arenal Tepepan, Tlalpan, CP 14610, Mexico City, Mexico
| | - M Pérez-Domínguez
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - K Torres-Arciga
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, UNAM, Avenida San Fernando No. 22, Colonia Sección XVI, Tlalpan, CP 14080, Mexico City, Mexico
| | - R Rebollar-Vega
- Genomics Laboratory, Red de Apoyo a La Investigación - CIC, Universidad Nacional Autónoma de México, INMCNSZ, Vasco de Quiroga 15, Belisario Domínguez Secc. 16, Tlalpan, 14080, Mexico City, Mexico
| | - I A De la Rosa-Velázquez
- Genomics Laboratory, Red de Apoyo a La Investigación - CIC, Universidad Nacional Autónoma de México, INMCNSZ, Vasco de Quiroga 15, Belisario Domínguez Secc. 16, Tlalpan, 14080, Mexico City, Mexico
- Next Generation Sequencing Core Facility, Helmholtz Zentrum Muenchen, Ingolstaedter Landstr 1, 85754, Neuherberg, Germany
| | - C Arriaga-Canon
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, UNAM, Avenida San Fernando No. 22, Colonia Sección XVI, Tlalpan, CP 14080, Mexico City, Mexico
| | - L A Herrera
- Instituto Nacional de Medicina Genómica, Periférico Sur 4809, Arenal Tepepan, Tlalpan, CP 14610, Mexico City, Mexico
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, UNAM, Avenida San Fernando No. 22, Colonia Sección XVI, Tlalpan, CP 14080, Mexico City, Mexico
| | - Clorinda Arias
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, México.
| | - Rodrigo González-Barrios
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, UNAM, Avenida San Fernando No. 22, Colonia Sección XVI, Tlalpan, CP 14080, Mexico City, Mexico.
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15
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Quarta C, Claret M, Zeltser LM, Williams KW, Yeo GSH, Tschöp MH, Diano S, Brüning JC, Cota D. POMC neuronal heterogeneity in energy balance and beyond: an integrated view. Nat Metab 2021; 3:299-308. [PMID: 33633406 PMCID: PMC8085907 DOI: 10.1038/s42255-021-00345-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 01/13/2021] [Indexed: 01/31/2023]
Abstract
Hypothalamic AgRP and POMC neurons are conventionally viewed as the yin and yang of the body's energy status, since they act in an opposite manner to modulate appetite and systemic energy metabolism. However, although AgRP neurons' functions are comparatively well understood, a unifying theory of how POMC neuronal cells operate has remained elusive, probably due to their high level of heterogeneity, which suggests that their physiological roles might be more complex than initially thought. In this Perspective, we propose a conceptual framework that integrates POMC neuronal heterogeneity with appetite regulation, whole-body metabolic physiology and the development of obesity. We highlight emerging evidence indicating that POMC neurons respond to distinct combinations of interoceptive signals and food-related cues to fine-tune divergent metabolic pathways and behaviours necessary for survival. The new framework we propose reflects the high degree of developmental plasticity of this neuronal population and may enable progress towards understanding of both the aetiology and treatment of metabolic disorders.
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Affiliation(s)
- Carmelo Quarta
- University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, INSERM U1215, Bordeaux, France
| | - Marc Claret
- Neuronal Control of Metabolism (NeuCoMe) Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red (CIBER), Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Barcelona, Spain
| | - Lori M Zeltser
- Naomi Berrie Diabetes Center, Columbia University, New York, NY, USA
- Department of Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Kevin W Williams
- Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Giles S H Yeo
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - Matthias H Tschöp
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Division of Metabolic Diseases, Department of Medicine, Technische Universität, Munich, Germany
| | - Sabrina Diano
- Institute of Human Nutrition, Columbia University Irving Medical Center, New York, NY, USA
- Department of Molecular Pharmacology and Therapeutics, Columbia University Irving Medical Center, New York, NY, USA
| | - Jens C Brüning
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Cologne, Germany
- Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Cologne, Germany
- Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- National Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Daniela Cota
- University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, INSERM U1215, Bordeaux, France.
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16
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Iqbal NJ, Schwartz GJ, Zhao H, Zhu L, Chua S. Cyclin-dependent kinase 4/6 inhibitors require an arcuate-to-paraventricular hypothalamus melanocortin circuit to treat diet-induced obesity. Am J Physiol Endocrinol Metab 2021; 320:E467-E474. [PMID: 33356996 PMCID: PMC7988782 DOI: 10.1152/ajpendo.00386.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The arcuate nucleus (ARC) of the hypothalamus comprises two antagonistic neuron populations critical for energy balance, namely, the anorexigenic pro-opiomelanocortin (POMC) and the orexigenic agouti-related peptide (AgRP) neurons that act as agonists and antagonists, respectively, for neurons expressing the type IV melanocortin receptor (MC4R) (Andermann ML and Lowell BB. Neuron 95: 757-778, 2017). MC4R activation increases energy expenditure and decreases food intake during positive energy balance states to prevent diet-induced obesity (DIO). Work from our group identified aberrant neuronal cell cycle events both as a novel biomarker and druggable target in the ARC for the treatment of DIO, demonstrating pharmacological restoration of retinoblastoma protein function in the ARC using cyclin-dependent kinase 4/6 (CDK4/6) inhibitors could treat DIO in mice by increasing lipid oxidation to selectively decrease fat mass. However, the role of CDK4/6 inhibitors on food intake was not examined. Four-week-old Mc4r-loxTB mice were continuously administered high-fat diet (60% kcal fat). At 8 wk of age, animals were administered 60 mg/kg abemaciclib orally or a saline control and monitored every 2 wk for fat mass changes by MRI. At 11 wk of age, all animals were injected bilaterally in the paraventricular hypothalamus with AAV8 serotype virus expressing a Cre-mCherry and monitored for another 5 wk. Restoration of Mc4r expression in the paraventricular hypothalamic nucleus (PVN/PVH) reduced food intake in hyperphagic obese mice when given CDK4/6 inhibitor therapy. The reduced food intake was responsible for reduced fat mass in mice treated with abemaciclib. These results indicate that targeting POMC neurons could be an effective strategy in treating diet-related obesity.NEW & NOTEWORTHY We have defined some of the necessary components to prevent high-fat diet-induced obesity at the molecular and cellular level. Within POMC neurons, the retinoblastoma protein must remain active and prevented from phosphoinactivation by cyclin-dependent kinases. The downstream neurons within the PVH must also properly express MC4R for the circuit to appropriately regulate feeding behavior.
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Affiliation(s)
- Niloy Jafar Iqbal
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Gary J Schwartz
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York
| | - Hongling Zhao
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Liang Zhu
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Streamson Chua
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York
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17
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Kalsbeek MJT, Yi CX. The infundibular peptidergic neurons and glia cells in overeating, obesity, and diabetes. HANDBOOK OF CLINICAL NEUROLOGY 2021; 180:315-325. [PMID: 34225937 DOI: 10.1016/b978-0-12-820107-7.00019-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Dysfunctional regulation of energy homeostasis results in increased bodyweight and obesity, eventually leading to type 2 diabetes mellitus. The infundibular nucleus (IFN) of the hypothalamus is the main regulator of energy homeostasis. The peptidergic neurons and glia cells of the IFN receive metabolic cues concerning energy state of the body from the circulation. The IFN can monitor hormones like insulin and leptin and nutrients like glucose and fatty acids. All these metabolic cues are integrated into an output signal regulating energy homeostasis through the release of neuropeptides. These neuropeptides are released in several inter- and extrahypothalamic brain regions involved in regulation of energy homeostasis. This review will give an overview of the peripheral signals involved in the regulation of energy homeostasis, the peptidergic neurons and glial cells of the IFN, and will highlight the main intra-hypothalamic projection sites of the IFN.
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Affiliation(s)
- Martin J T Kalsbeek
- Laboratory of Endocrinology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam Gastroenterology Metabolism, Amsterdam, The Netherlands; Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
| | - Chun-Xia Yi
- Laboratory of Endocrinology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam Gastroenterology Metabolism, Amsterdam, The Netherlands; Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands; Department of Endocrinology and Metabolism, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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18
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Abstract
Energy balance is centrally regulated by the brain through several interacting neuronal systems involving external, peripheral, and central factors within the brain. The hypothalamus integrates these factors and is the key brain area in the regulation of energy balance. In this review, we will explain the structure of the hypothalamus and its role in the regulation of energy balance. An important part of energy balance regulation is the sensing of nutrient status and availability. This review will focus on the sensing of the two main sources of energy by the hypothalamus: glucose and fat. As many common health problems and chronic diseases can be traced back to a disrupted hypothalamic function, we will also discuss hypothalamic sensing of glucose and fats in these pathologies. Finally, we will summarize the current knowledge and discuss how this may be applied clinically and for future research perspectives.
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19
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Fan Y, Han Z, Lu X, Zhang H, Arbab AAI, Loor JJ, Yang Y, Yang Z. Identification of Milk Fat Metabolism-Related Pathways of the Bovine Mammary Gland during Mid and Late Lactation and Functional Verification of the ACSL4 Gene. Genes (Basel) 2020; 11:genes11111357. [PMID: 33207796 PMCID: PMC7696932 DOI: 10.3390/genes11111357] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 11/13/2020] [Indexed: 12/26/2022] Open
Abstract
The concentration of bovine milk fat changes regularly with lactation stages. In particular, milk fat percentage is higher in late lactation than mid lactation. Furthermore, milk fat composition is highly subject to a few genes. Thus, transcriptome sequencing was performed to explore the expression patterns of differentially-expressed genes (DEGs) in the parenchymal mammary gland of Holstein dairy cows between mid and late lactation. The 725 DEGs were screened (fold change > 2 and p-value < 0.05), and the peroxisome proliferator-activated receptor (PPAR) signaling pathway associated with lipid synthesis had a significant variation between the two periods (p-value < 0.05). The activation of the PPAR signal pathway may a key factor in the increasing of milk fat content in late lactation compared to mid lactation. Acyl-CoA synthetase long-chain family member 4 (ACSL4), a member of the PPAR signaling pathway, was upregulated in late lactation compared to mid lactation (p < 0.05). ACSL4 catalyzes the activation of long-chain fatty acids for cellular lipid synthesis. However, it remains uncertain that the molecular mechanism of milk fat synthesis is regulated by ACSL4 in dairy cows. Subsequently, the function verification of ACSL4 was performed in bovine mammary epithelial cells (BMECs). The upregulated expression of ACSL4 was accompanied by the increase of the concentration of intracellular triglycerides, whereas knockdown of ACSL4 decreased the concentration of intracellular triglycerides, which demonstrated that ACSL4 plays an important role in modulating milk fat synthesis. In conclusion, the results displayed that ACSL4 expression regulates triglyceride metabolism in ruminant mammary cells.
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Affiliation(s)
- Yongliang Fan
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Y.F.); (Z.H.); (X.L.); (H.Z.); (A.A.I.A.)
- Joint International Research Laboratory of Agriculture & Agri-Product Safety, Ministry of Education, Yangzhou University, Yangzhou 225009, China
| | - Ziyin Han
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Y.F.); (Z.H.); (X.L.); (H.Z.); (A.A.I.A.)
- Joint International Research Laboratory of Agriculture & Agri-Product Safety, Ministry of Education, Yangzhou University, Yangzhou 225009, China
| | - Xubin Lu
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Y.F.); (Z.H.); (X.L.); (H.Z.); (A.A.I.A.)
- Joint International Research Laboratory of Agriculture & Agri-Product Safety, Ministry of Education, Yangzhou University, Yangzhou 225009, China
| | - Huimin Zhang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Y.F.); (Z.H.); (X.L.); (H.Z.); (A.A.I.A.)
- Joint International Research Laboratory of Agriculture & Agri-Product Safety, Ministry of Education, Yangzhou University, Yangzhou 225009, China
| | - Abdelaziz Adam Idriss Arbab
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Y.F.); (Z.H.); (X.L.); (H.Z.); (A.A.I.A.)
- Joint International Research Laboratory of Agriculture & Agri-Product Safety, Ministry of Education, Yangzhou University, Yangzhou 225009, China
| | - Juan J. Loor
- Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA;
| | - Yi Yang
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China;
| | - Zhangping Yang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Y.F.); (Z.H.); (X.L.); (H.Z.); (A.A.I.A.)
- Joint International Research Laboratory of Agriculture & Agri-Product Safety, Ministry of Education, Yangzhou University, Yangzhou 225009, China
- Correspondence: ; Tel.: +86-0514-87979269
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20
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Haigh JL, New LE, Filippi BM. Mitochondrial Dynamics in the Brain Are Associated With Feeding, Glucose Homeostasis, and Whole-Body Metabolism. Front Endocrinol (Lausanne) 2020; 11:580879. [PMID: 33240218 PMCID: PMC7680879 DOI: 10.3389/fendo.2020.580879] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/05/2020] [Indexed: 12/13/2022] Open
Abstract
The brain is responsible for maintaining whole-body energy homeostasis by changing energy input and availability. The hypothalamus and dorsal vagal complex (DVC) are the primary sites of metabolic control, able to sense both hormones and nutrients and adapt metabolism accordingly. The mitochondria respond to the level of nutrient availability by fusion or fission to maintain energy homeostasis; however, these processes can be disrupted by metabolic diseases including obesity and type II diabetes (T2D). Mitochondrial dynamics are crucial in the development and maintenance of obesity and T2D, playing a role in the control of glucose homeostasis and whole-body metabolism across neurons and glia in the hypothalamus and DVC.
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Affiliation(s)
| | | | - Beatrice M. Filippi
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom
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21
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Li Y, Wu H, Zhang R, Shu G, Wang S, Gao P, Zhu X, Jiang Q, Wang L. Diet containing stearic acid increases food reward-related behaviors in mice compared with oleic acid. Brain Res Bull 2020; 164:45-54. [PMID: 32822805 DOI: 10.1016/j.brainresbull.2020.08.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 07/30/2020] [Accepted: 08/10/2020] [Indexed: 10/23/2022]
Abstract
Obesity is currently a worldwide phenomenon. The consumption of calorie-rich foods is responsible for most obesity cases, but not all humans exposed to high-calorie diets develop obesity. According to recent studies, exposure to fat-rich diets may be the actual cause of obesity. Dietary long-chain fatty acids affect brain function and are linked to food intake and motivation-related behaviors. Recently, many studies have shown that different types of fatty acids play different roles in animals. In our study, the effects of stearic acid (a saturated fatty acid) and oleic acid (a monounsaturated fatty acid) in diets on hedonic feeding behaviors were investigated, and changes of feeding-related protein levels in the brain were detected to explore the possible mechanism underlying the effects of these fatty acids. As a result, mice fed a diet containing stearic acid, compared to a diet containing oleic acid, exhibited increased food intake, hedonic eating, and an operant response to sucrose and locomotor activity. Furthermore, stearic acid corresponded to a higher level of leptin in serum than oleic acid. In addition, the stearic acid treated group had lower protein levels of p-JAK2 and p-STAT3 in the VTA and a higher dopamine concentration in the NAc than the oleic acid-treated group. Meanwhile, the protein level of TH in the NAc was higher and the protein level of the DA transporter in the VTA was lower in the stearic acid-fed group than in the oleic acid-fed group. In conclusion, these findings indicated that a diet containing stearic acid can increase hedonic feeding behavior and affect mesolimbic dopamine system signals in mice. Moreover, the lowering of serum leptin and leptin signaling in the VTA may contribute to this effect.
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Affiliation(s)
- Yongxiang Li
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Hanyu Wu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Ruixue Zhang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Gang Shu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Songbo Wang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Ping Gao
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Xiaotong Zhu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Qingyan Jiang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China.
| | - Lina Wang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China.
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22
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Michael NJ, Watt MJ. Long Chain Fatty Acids Differentially Regulate Sub-populations of Arcuate POMC and NPY Neurons. Neuroscience 2020; 451:164-173. [PMID: 33002557 DOI: 10.1016/j.neuroscience.2020.09.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 09/09/2020] [Accepted: 09/21/2020] [Indexed: 02/07/2023]
Abstract
Long chain fatty acids (LCFAs) have been suggested to influence the activity of hypothalamic neurons, however, limited studies have attempted to identify the neurochemical phenotype of these neurons. We aimed to determine if physiological levels of LCFAs alter the electrical excitability of pro-opiomelanocortin (POMC) and neuropeptide Y (NPY) neurons in the arcuate nucleus of the hypothalamus. We utilised whole-cell patch-clamp electrophysiology on brain slice preparations from genetic mouse models where green fluorescent protein was expressed in either POMC or NPY expressing cells. All animals had undergone an overnight fast to replicate conditions in which fatty acids would usually increase. Bath application of LCFAs were found to predominantly inhibit POMC neurons and predominantly excite NPY neurons. Differences between oleic and palmitic acid were not observed. These results suggest that LCFAs in the cerebrospinal fluid exert an underlying orexigenic tone to key hypothalamic neurons known to regulate energy homeostasis.
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Affiliation(s)
- Natalie J Michael
- Metabolic Disease, Obesity and Diabetes Program, Biomedicine Discovery Institute and the Department of Physiology, Monash University, Clayton 3800, VIC, Australia; Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City G1V4G5, Québec, Canada.
| | - Matthew J Watt
- Department of Physiology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne 3010, VIC, Australia
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23
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Jagannathan L, Socks E, Balasubramanian P, McGowan R, Herdt TM, Kianian R, MohanKumar SMJ, MohanKumar PS. Oleic acid stimulates monoamine efflux through PPAR-α: Differential effects in diet-induced obesity. Life Sci 2020; 255:117867. [PMID: 32479954 DOI: 10.1016/j.lfs.2020.117867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/20/2020] [Accepted: 05/26/2020] [Indexed: 01/13/2023]
Abstract
Obesity continues to be a growing health concern around the world, and elevated levels of free fatty acids as a result of high-fat intake might play a role in neuroendocrine alterations leading to obesity. However, it is unclear how fatty acids affect neuroendocrine functions and energy metabolism. Since hypothalamic monoamines play a crucial role in regulating neuroendocrine functions relating to energy balance, we investigated the direct effects of oleic acid on hypothalamic monoamines and hypothesized that oleic acid would activate peroxisome proliferator-activated receptor alpha (PPAR-α), a nuclear transcription factor involved with fatty acid metabolism, to affect monoamines. We also hypothesized that this response would be subdued in diet-induced obesity (DIO). To test these hypotheses, hypothalami from Sprague Dawley and DIO rats were incubated with 0 (Control), 0.00132 mM, 0.132 mM, 1.32 mM oleic acid, 50 μM MK 886 (a selective PPAR- α antagonist), or oleic acid + MK 886 in Krebs Ringers Henseleit (KRH) solution. HPLC-EC was used to measure monoamine levels in perfusates. Oleic acid produced a significant increase in norepinephrine, dopamine, and serotonin levels in a dose-dependent manner, and incubation with MK886 blocked these effects. The effect of oleic acid on hypothalamic monoamines was attenuated in DIO rats. These findings suggest that PPARα probably plays an essential role in fatty acid sensing in the hypothalamus, by affecting monoamine efflux and DIO rats are resistant to the effects of oleic acid.
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Affiliation(s)
- Lakshmikripa Jagannathan
- Neuroendocrine Research Laboratory, Departments of Pathobiology and Diagnostic Investigation, USA
| | - Emily Socks
- Neuroendocrine Research Laboratory, Departments of Pathobiology and Diagnostic Investigation, USA
| | | | - Robert McGowan
- Neuroendocrine Research Laboratory, Departments of Pathobiology and Diagnostic Investigation, USA
| | - Thomas M Herdt
- Diagnostic Center for Population and Animal Health, Michigan State University, E. Lansing, MI 48824, USA
| | - Reza Kianian
- Neuroendocrine Research Laboratory, Department of Veterinary Biosciences and Diagnostic Imaging, College of Veterinary Medicine, University of Georgia, Athens, GA 30606, USA
| | - Sheba M J MohanKumar
- Neuroendocrine Research Laboratory, Department of Veterinary Biosciences and Diagnostic Imaging, College of Veterinary Medicine, University of Georgia, Athens, GA 30606, USA
| | - P S MohanKumar
- Neuroendocrine Research Laboratory, Department of Veterinary Biosciences and Diagnostic Imaging, College of Veterinary Medicine, University of Georgia, Athens, GA 30606, USA.
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24
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Haynes VR, Michael NJ, van den Top M, Zhao FY, Brown RD, De Souza D, Dodd GT, Spanswick D, Watt MJ. A Neural basis for Octanoic acid regulation of energy balance. Mol Metab 2020; 34:54-71. [PMID: 32180560 PMCID: PMC7011014 DOI: 10.1016/j.molmet.2020.01.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 12/11/2019] [Accepted: 01/03/2020] [Indexed: 12/13/2022] Open
Abstract
Objectives Nutrient sensing by hypothalamic neurons is critical for the regulation of food intake and energy expenditure. We aimed to identify long- and medium-chain fatty acid species transported into the brain, their effects on energy balance, and the mechanisms by which they regulate activity of hypothalamic neurons. Methods Simultaneous blood and cerebrospinal fluid (CSF) sampling was undertaken in rats and metabolic analyses using radiolabeled fatty acid tracers were performed on mice. Electrophysiological recording techniques were used to investigate signaling mechanisms underlying fatty acid-induced changes in activity of pro-opiomelanocortin (POMC) neurons. Results Medium-chain fatty acid (MCFA) octanoic acid (C8:0), unlike long-chain fatty acids, was rapidly transported into the hypothalamus of mice and almost exclusively oxidized, causing rapid, transient reductions in food intake and increased energy expenditure. Octanoic acid differentially regulates the excitability of POMC neurons, activating these neurons directly via GPR40 and inducing inhibition via an indirect non-synaptic, purine, and adenosine receptor-dependent mechanism. Conclusions MCFA octanoic acid is a central signaling nutrient that targets POMC neurons via distinct direct and indirect signal transduction pathways to instigate changes in energy status. These results could explain the beneficial health effects that accompany MCFA consumption. Octanoic acid (C8:0) is rapidly transported from blood to the cerebrospinal fluid. Octanoic acid rapidly reduces food intake and increases energy expenditure. Octanoic acid targets POMC neurons through direct and indirect signaling pathways. Activation of POMC neurons occurs directly through GPR40. Inhibition occurs through a nonsynaptic, purine and adenosine receptor-dependent mechanism.
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Affiliation(s)
- Vanessa R Haynes
- Department of Physiology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, 3010, VIC, Australia; Metabolic Disease, Obesity and Diabetes Program, Biomedicine Discovery Institute and the Department of Physiology, Monash University, Clayton, 3800, VIC, Australia
| | - Natalie J Michael
- Metabolic Disease, Obesity and Diabetes Program, Biomedicine Discovery Institute and the Department of Physiology, Monash University, Clayton, 3800, VIC, Australia; Center for Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA
| | | | | | - Russell D Brown
- Metabolic Disease, Obesity and Diabetes Program, Biomedicine Discovery Institute and the Department of Physiology, Monash University, Clayton, 3800, VIC, Australia
| | - David De Souza
- Metabolomics Australia, Bio21 Institute, University of Melbourne, Parkville, 3010, VIC, Australia
| | - Garron T Dodd
- Department of Physiology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, 3010, VIC, Australia
| | - David Spanswick
- Metabolic Disease, Obesity and Diabetes Program, Biomedicine Discovery Institute and the Department of Physiology, Monash University, Clayton, 3800, VIC, Australia; Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK; NeuroSolutions Ltd, Coventry, UK.
| | - Matthew J Watt
- Department of Physiology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, 3010, VIC, Australia.
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25
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Luo H, Liang XF, Li J, Zhang Y, Xiao Q, Peng B, Zhang Z. Effect of long-chain saturated and unsaturated fatty acids on hypothalamic fatty acid sensing in Chinese perch (Siniperca chuatsi). Comp Biochem Physiol B Biochem Mol Biol 2019; 241:110395. [PMID: 31887407 DOI: 10.1016/j.cbpb.2019.110395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 12/13/2019] [Accepted: 12/19/2019] [Indexed: 12/13/2022]
Abstract
In order to evaluate fatty acid (FA) sensing systems based on binding to FAT/CD36 in hypothalamus of Chinese perch (Siniperca chuatsi) and its sensitivity to FAs with the same chain length and different unsaturation levels. The effects of Stearate (SA; C18:0), oleate (OA; C18:1 n-9), linoleic acid (LA; C18:2 n-6), and α-linolenic acid (ALA; C18:3 n-3) on hypothalamic FA sensing were evaluated by intracerebroventricular (ICV) administration. Food intake was assessed after 2, 4, 6, 8 and 12 h. Gene expression associated with FA sensing mechanism such as cd36, pparα and srebp1c, and neuropeptides controlling appetite such as pomca, cart, agrp2 and npy were assessed after 6 h. The ICV treatment of OA, LA and ALA activated FAT/CD36 and PPARα, rather than SA, and modulated gene expression levels of hypothalamic neuropeptides associated with appetite. And then, OA, LA and ALA inhibited food intake, which was consistent with the activation of hypothalamus FA sensing. Our data indicated some mechanisms of the hypothalamic FA sensing systems also existed in Chinese perch. It's worth noting that polyunsaturated fatty acids (PUFA) could also activate hypothalamic FA sensing mechanisms in Chinese perch. The unsaturation of FA appears to be extremely important for FA sensing mechanisms, since no major influences in Chinese perch after SA treatment. Our findings will contribute to the study of long-chain FAs sensing mechanisms in fish hypothalamus and highlight the importance of PUFAs in fish species.
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Affiliation(s)
- Haocan Luo
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan 430070, China; Innovation Base for Chinese Perch Breeding, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, China
| | - Xu-Fang Liang
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan 430070, China; Innovation Base for Chinese Perch Breeding, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, China.
| | - Jiao Li
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan 430070, China; Innovation Base for Chinese Perch Breeding, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, China
| | - Yanpeng Zhang
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan 430070, China; Innovation Base for Chinese Perch Breeding, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, China
| | - Qianqian Xiao
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan 430070, China; Innovation Base for Chinese Perch Breeding, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, China
| | - Binbin Peng
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan 430070, China; Innovation Base for Chinese Perch Breeding, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, China
| | - Zhilu Zhang
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan 430070, China; Innovation Base for Chinese Perch Breeding, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, China
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26
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Park S, Oh TS, Kim S, Kim EK. Palmitate-induced autophagy liberates monounsaturated fatty acids and increases Agrp expression in hypothalamic cells. Anim Cells Syst (Seoul) 2019; 23:384-391. [PMID: 31853375 PMCID: PMC6913639 DOI: 10.1080/19768354.2019.1696407] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 11/15/2019] [Indexed: 12/13/2022] Open
Abstract
Fatty acids regulate food intake, although the exact mechanism remains unknown. Emerging evidence suggests that intracellular free fatty acids generated by starvation-induced autophagy regulate food intake. Starvation for 6 h elevated fatty acids such as palmitate, oleate, arachidonate, eicosatrienoate, and docosahexaenoate in the mouse serum. Among them, palmitate induced lipophagy, an autophagic degradation of cellular lipid droplets, in agouti-related peptide (Agrp)-expressing hypothalamic cells. Palmitate-induced lipophagy increased both Agrp expression and the contents of monounsaturated fatty acids such as palmitoleate, oleate, and (E)-9-octadecanoate, whereas these effects were blunted by autophagy deficiency. These findings support the role of free fatty acids in hypothalamic autophagy that regulates the appetite by changing the expression of orexigenic neuropeptides.
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Affiliation(s)
- Seokjae Park
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea.,Neurometabolomics Research Center, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Tae Seok Oh
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Seolsong Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Eun-Kyoung Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea.,Neurometabolomics Research Center, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
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27
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Morita-Takemura S, Wanaka A. Blood-to-brain communication in the hypothalamus for energy intake regulation. Neurochem Int 2019; 128:135-142. [DOI: 10.1016/j.neuint.2019.04.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 04/08/2019] [Accepted: 04/11/2019] [Indexed: 01/03/2023]
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28
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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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29
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Ramírez-Sánchez M, Prieto I, Segarra AB, Martínez-Cañamero M, Banegas I, de Gasparo M. Enkephalinase regulation. VITAMINS AND HORMONES 2019; 111:105-129. [PMID: 31421697 DOI: 10.1016/bs.vh.2019.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
After millennia of knowledge of opium, it was only recently that endogenous substances called opioids with similar properties to opium and derivatives were discovered. The first to be discovered were enkephalins. In addition to the regulation of their synthesis and expression of receptors, an important mechanism for the regulation of their functions carried out by multiple proteolytic enzymes acting at all levels of their structure is described. The action of such enzymes, known as enkephalinases, is also regulated by endogenous and exogenous factors which ultimately affect the control of the enkephalins's action. For therapeutic purposes, it is not only necessary to develop specific inhibitors but also to acquire a deep knowledge of the influence that such factors exert on their activities. This knowledge could help us to establish adapted therapeutic strategies in the treatment of pain or other processes in which enkephalinases are involved. In this chapter, some of these regulatory factors are discussed, such as regional and subcellular distribution, developmental changes, diurnal variations, hormonal influences, stress, dietary factors or interactions with other neurotransmitters.
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Affiliation(s)
| | - Isabel Prieto
- Department of Health Sciences, University of Jaén, Jaén, Spain
| | | | | | | | - Marc de Gasparo
- Cardiovascular & Metabolic Syndrome Adviser, Rossemaison, Switzerland
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30
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McIlwraith EK, Loganathan N, Belsham DD. Phoenixin Expression Is Regulated by the Fatty Acids Palmitate, Docosahexaenoic Acid and Oleate, and the Endocrine Disrupting Chemical Bisphenol A in Immortalized Hypothalamic Neurons. Front Neurosci 2018; 12:838. [PMID: 30524225 PMCID: PMC6262291 DOI: 10.3389/fnins.2018.00838] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 10/29/2018] [Indexed: 01/22/2023] Open
Abstract
Phoenixin (PNX) is a newly identified reproductive peptide required for the estrous cycle. It is most highly expressed in the hypothalamus, where it is a positive regulator of gonadotropin-releasing hormone (GnRH) and kisspeptin. However, it is unknown what signals lie upstream of Pnx to coordinate its effects on GnRH and kisspeptin. We investigated the effects of the hormones, estrogen and leptin; the fatty acids, palmitate, docosahexaenoic acid (DHA), oleate and palmitoleate; and the endocrine disrupting chemical BPA on Pnx mRNA levels. We also examined whether the signaling pathways of nitric oxide, lipopolysaccharide, cAMP and protein kinase C could alter Pnx expression. Immortalized hypothalamic neurons were treated from 2 to 24 h with these compounds and Pnx mRNA levels were measured with RT-qPCR. Unexpectedly, only BPA as well as the fatty acids, palmitate, DHA and oleate, could alter Pnx expression; therefore suggesting that Pnx may fulfill a nutrient-sensing role in the hypothalamus. Our study is the first to delineate potential regulators of this novel neuropeptide, and our findings provide some insight into the functional role of PNX in the hypothalamus.
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Affiliation(s)
- Emma K McIlwraith
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Neruja Loganathan
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Denise D Belsham
- Department of Physiology, University of Toronto, Toronto, ON, Canada.,Department of Obstetrics and Gynaecology, University of Toronto, Toronto, ON, Canada.,Department of Medicine, University of Toronto, Toronto, ON, Canada
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31
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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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32
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Timper K, Paeger L, Sánchez-Lasheras C, Varela L, Jais A, Nolte H, Vogt MC, Hausen AC, Heilinger C, Evers N, Pospisilik JA, Penninger JM, Taylor EB, Horvath TL, Kloppenburg P, Brüning JC. Mild Impairment of Mitochondrial OXPHOS Promotes Fatty Acid Utilization in POMC Neurons and Improves Glucose Homeostasis in Obesity. Cell Rep 2018; 25:383-397.e10. [PMID: 30304679 PMCID: PMC6349418 DOI: 10.1016/j.celrep.2018.09.034] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 06/06/2018] [Accepted: 09/11/2018] [Indexed: 01/19/2023] Open
Abstract
Mitochondrial oxidative phosphorylation (OXPHOS) and substrate utilization critically regulate the function of hypothalamic proopiomelanocortin (POMC)-expressing neurons. Here, we demonstrate that inactivation of apoptosis-inducing factor (AIF) in POMC neurons mildly impairs mitochondrial respiration and decreases firing of POMC neurons in lean mice. In contrast, under diet-induced obese conditions, POMC-Cre-specific inactivation of AIF prevents obesity-induced silencing of POMC neurons, translating into improved glucose metabolism, improved leptin, and insulin sensitivity, as well as increased energy expenditure in AIFΔPOMC mice. On a cellular level, AIF deficiency improves mitochondrial morphology, facilitates the utilization of fatty acids for mitochondrial respiration, and increases reactive oxygen species (ROS) formation in POMC neurons from obese mice, ultimately leading to restored POMC firing upon HFD feeding. Collectively, partial impairment of mitochondrial function shifts substrate utilization of POMC neurons from glucose to fatty acid metabolism and restores their firing properties, resulting in improved systemic glucose and energy metabolism in obesity.
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Affiliation(s)
- Katharina Timper
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Lars Paeger
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany; Biocenter, University of Cologne, Cologne, Germany
| | - Carmen Sánchez-Lasheras
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Luis Varela
- Department of Biochemistry and Fraternal Order of Eagles Diabetes Research Center, Caver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Alexander Jais
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Hendrik Nolte
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Merly C Vogt
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - A Christine Hausen
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Christian Heilinger
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Nadine Evers
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - J Andrew Pospisilik
- Max-Planck-Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany
| | - Josef M Penninger
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohr Gasse 3, 1030 Vienna, Austria
| | - Eric B Taylor
- Department of Biochemistry and Fraternal Order of Eagles Diabetes Research Center, Caver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Tamas L Horvath
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary
| | - Peter Kloppenburg
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany; Biocenter, University of Cologne, Cologne, Germany
| | - Jens Claus Brüning
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
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Heeley N, Kirwan P, Darwish T, Arnaud M, Evans ML, Merkle FT, Reimann F, Gribble FM, Blouet C. Rapid sensing of l-leucine by human and murine hypothalamic neurons: Neurochemical and mechanistic insights. Mol Metab 2018; 10:14-27. [PMID: 29439854 PMCID: PMC5985239 DOI: 10.1016/j.molmet.2018.01.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 01/24/2018] [Accepted: 01/29/2018] [Indexed: 11/27/2022] Open
Abstract
Objective Dietary proteins are sensed by hypothalamic neurons and strongly influence multiple aspects of metabolic health, including appetite, weight gain, and adiposity. However, little is known about the mechanisms by which hypothalamic neural circuits controlling behavior and metabolism sense protein availability. The aim of this study is to characterize how neurons from the mediobasal hypothalamus respond to a signal of protein availability: the amino acid l-leucine. Methods We used primary cultures of post-weaning murine mediobasal hypothalamic neurons, hypothalamic neurons derived from human induced pluripotent stem cells, and calcium imaging to characterize rapid neuronal responses to physiological changes in extracellular l-Leucine concentration. Results A neurochemically diverse subset of both mouse and human hypothalamic neurons responded rapidly to l-leucine. Consistent with l-leucine's anorexigenic role, we found that 25% of mouse MBH POMC neurons were activated by l-leucine. 10% of MBH NPY neurons were inhibited by l-leucine, and leucine rapidly reduced AGRP secretion, providing a mechanism for the rapid leucine-induced inhibition of foraging behavior in rodents. Surprisingly, none of the candidate mechanisms previously implicated in hypothalamic leucine sensing (KATP channels, mTORC1 signaling, amino-acid decarboxylation) were involved in the acute activity changes produced by l-leucine. Instead, our data indicate that leucine-induced neuronal activation involves a plasma membrane Ca2+ channel, whereas leucine-induced neuronal inhibition is mediated by inhibition of a store-operated Ca2+ current. Conclusions A subset of neurons in the mediobasal hypothalamus rapidly respond to physiological changes in extracellular leucine concentration. Leucine can produce both increases and decreases in neuronal Ca2+ concentrations in a neurochemically-diverse group of neurons, including some POMC and NPY/AGRP neurons. Our data reveal that leucine can signal through novel mechanisms to rapidly affect neuronal activity. A neurochemically diverse group of mouse and human hypothalamic neurons rapidly sense and respond to l-leucine. Leucine can produce neuronal activation or neuronal inhibition via distinct and novel Ca2+ signaling mechanisms. Leucine activates 25% ARH POMC neurons. Leucine inhibits 10% ARH NPY/AGRP neurons and reduces AGRP secretion from fasted mediobasal hypothalamic slices.
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Affiliation(s)
- Nicholas Heeley
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK
| | - Peter Kirwan
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK
| | - Tamana Darwish
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK
| | - Marion Arnaud
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK
| | - Mark L Evans
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK
| | - Florian T Merkle
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK
| | - Frank Reimann
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK
| | - Fiona M Gribble
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK
| | - Clemence Blouet
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, WT-MRC Institute of Metabolic Science, University of Cambridge, Cambridge CB2 OQQ, UK.
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Chung WY, Han JW, Heo W, Lee MG, Kim JY. Overexpression of WNK1 in POMC-expressing neurons reduces weigh gain via WNK4-mediated degradation of Kir6.2. Mol Cell Biochem 2018; 447:165-174. [PMID: 29392534 DOI: 10.1007/s11010-018-3301-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/24/2018] [Indexed: 10/18/2022]
Abstract
"With no lysine" (WNK) kinases have been shown to regulate various ion transporters in various tissues, but studies on the function of WNK kinases in the brain have been limited. In this study, we discovered that WNK1 and WNK4 in POMC-expressing neuronal cells in WNK1 overexpressed transgenic mice (WNK1 TG) decrease appetite via degradation of Kir6.2. Weight gain after 20 weeks of age was delayed in WNK1 TG mice as a result of reduced food intake. Expression of WNK1 and proopiomelanocortin (POMC) was higher in POMC-expressing neurons in the hypothalamus of WNK1 TG mice than in WT mice. Immunostaining of serial sections of the hypothalamus revealed that POMC-expressing neurons were smaller in WNK1 TG mice than in WT mice. In addition, expression of Kir6.2 was significantly reduced in WNK1 TG mice. Overexpression and knockdown of WNK4 demonstrated that WNK4 regulates protein expression of Kir6.2 via protein-protein interaction. Accordingly, reduced age-dependent weight gain of WNK1 TG mice seems to be related with the decreased Kir6.2 expression via WNK1- and WNK4-regulated protein stability of Kir6.2.
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Affiliation(s)
- Woo Young Chung
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 120-752, South Korea
| | - Jung Woo Han
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 120-752, South Korea
| | - Woon Heo
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 120-752, South Korea
| | - Min Goo Lee
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 120-752, South Korea
| | - Joo Young Kim
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, 120-752, South Korea.
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Hryhorczuk C, Sheng Z, Décarie-Spain L, Giguère N, Ducrot C, Trudeau LÉ, Routh VH, Alquier T, Fulton S. Oleic Acid in the Ventral Tegmental Area Inhibits Feeding, Food Reward, and Dopamine Tone. Neuropsychopharmacology 2018; 43:607-616. [PMID: 28857071 PMCID: PMC5770761 DOI: 10.1038/npp.2017.203] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 08/23/2017] [Accepted: 08/28/2017] [Indexed: 12/16/2022]
Abstract
Long-chain fatty acids (FAs) act centrally to decrease food intake and hepatic glucose production and alter hypothalamic neuronal activity in a manner that depends on FA type and cellular transport proteins. However, it is not known whether FAs are sensed by ventral tegmental area (VTA) dopamine (DA) neurons to control food-motivated behavior and DA neurotransmission. We investigated the impact of the monounsaturated FA oleate in the VTA on feeding, locomotion, food reward, and DA neuronal activity and DA neuron expression of FA-handling proteins and FA uptake. A single intra-VTA injection of oleate, but not of the saturated FA palmitate, decreased food intake and increased locomotor activity. Furthermore, intra-VTA oleate blunted the rewarding effects of high-fat/sugar food in an operant task and inhibited DA neuronal firing. Using sorted DA neuron preparations from TH-eGFP mice we found that DA neurons express FA transporter and binding proteins, and are capable of intracellular transport of long-chain FA. Finally, we demonstrate that a transporter blocker attenuates FA uptake into DA neurons and blocks the effects of intra-VTA oleate to decrease food-seeking and DA neuronal activity. Together, these results suggest that DA neurons detect FA and that oleate has actions in the VTA to suppress DA neuronal activity and food seeking following cellular incorporation. These findings highlight the capacity of DA neurons to act as metabolic sensors by responding not only to hormones but also to FA nutrient signals to modulate food-directed behavior.
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Affiliation(s)
- Cecile Hryhorczuk
- CRCHUM and Montreal Diabetes Research Center, Montréal, QC, Canada
- Department of Physiology, Université de Montréal, Montréal, QC, Canada
| | - Zhenyu Sheng
- Rutgers New Jersey Medical School, Department of Pharmacology, Physiology and Neuroscience, Rutgers University, Newark, NJ, USA
| | - Léa Décarie-Spain
- CRCHUM and Montreal Diabetes Research Center, Montréal, QC, Canada
- Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
| | - Nicolas Giguère
- Department of Pharmacology, Université de Montréal, Montréal, QC, Canada
| | - Charles Ducrot
- Department of Pharmacology, Université de Montréal, Montréal, QC, Canada
| | - Louis-Éric Trudeau
- Department of Pharmacology, Université de Montréal, Montréal, QC, Canada
| | - Vanessa H Routh
- Rutgers New Jersey Medical School, Department of Pharmacology, Physiology and Neuroscience, Rutgers University, Newark, NJ, USA
| | - Thierry Alquier
- CRCHUM and Montreal Diabetes Research Center, Montréal, QC, Canada
- Department of Medicine, Université de Montréal, Montréal, QC, Canada
| | - Stephanie Fulton
- CRCHUM and Montreal Diabetes Research Center, Montréal, QC, Canada
- Department of Nutrition, Université de Montréal, Montréal, QC, Canada
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Argente-Arizón P, Díaz F, Ros P, Barrios V, Tena-Sempere M, García-Segura LM, Argente J, Chowen JA. The Hypothalamic Inflammatory/Gliosis Response to Neonatal Overnutrition Is Sex and Age Dependent. Endocrinology 2018; 159:368-387. [PMID: 29077836 DOI: 10.1210/en.2017-00539] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 10/20/2017] [Indexed: 01/10/2023]
Abstract
Astrocytes participate in both physiological and pathophysiological responses to metabolic and nutrient signals. Although most studies have focused on the astrocytic response to weight gain due to high-fat/high-carbohydrate intake, surplus intake of a balanced diet also induces excess weight gain. We have accessed the effects of neonatal overnutrition, which has both age- and sex-dependent effects on weight gain, on hypothalamic inflammation/gliosis. Although both male and female Wistar rats accumulate excessive fat mass as early as postnatal day (PND) 10 with neonatal overnutrition, no increase in hypothalamic cytokine levels, markers of astrocytes or microglia, or inflammatory signaling pathways were observed. At PND 50, no effect of neonatal overnutriton was found in either sex, whereas at PND 150, males again weighed significantly more than their controls, and this was coincident with an increase in markers of inflammation and astrogliosis in the hypothalamus. Circulating triglycerides and free fatty acids were also elevated in these males, but not in females or in either sex at PND 10. Thus, the effects of fatty acids and estrogens on astrocytes in vitro were analyzed. Our results indicate that changes in circulating fatty acid levels may be involved in the induction of hypothalamic inflammation/gliosis in excess weight gain, even on a normal diet, and that estrogens could participate in the protection of females from these processes. In conclusion, the interaction of developmental influences, dietary composition, age, and sex determines the central inflammatory response and the associated long-term outcomes of excess weight gain.
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Affiliation(s)
- Pilar Argente-Arizón
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Department of Pediatrics, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición, Instituto Carlos III, Madrid, Spain
| | - Francisca Díaz
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición, Instituto Carlos III, Madrid, Spain
| | - Purificación Ros
- Department of Pediatrics, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Hospital Universitario Puerto de Hierro-Majadahonda, Madrid, Spain
| | - Vicente Barrios
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición, Instituto Carlos III, Madrid, Spain
| | - Manuel Tena-Sempere
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición, Instituto Carlos III, Madrid, Spain
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Instituto Maimónides de Investigación Biomédica de Córdoba, Córdoba, Spain
| | - Luis Miguel García-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable, Instituto Carlos III, Madrid, Spain
| | - Jesús Argente
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Department of Pediatrics, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición, Instituto Carlos III, Madrid, Spain
- Instituto Madrileño de Estudios Svanzados Food Institute, Campus de Excelencia Internacional Universidad Autónoma de Madrid + Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Julie A Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- Centro de Investigación Biomédica en Red: Fisiopatología de la Obesidad y Nutrición, Instituto Carlos III, Madrid, Spain
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Abstract
The hypothalamus is an evolutionarily conserved brain structure that regulates an organism's basic functions, such as homeostasis and reproduction. Several hypothalamic nuclei and neuronal circuits have been the focus of many studies seeking to understand their role in regulating these basic functions. Within the hypothalamic neuronal populations, the arcuate melanocortin system plays a major role in controlling homeostatic functions. The arcuate pro-opiomelanocortin (POMC) neurons in particular have been shown to be critical regulators of metabolism and reproduction because of their projections to several brain areas both in and outside of the hypothalamus, such as autonomic regions of the brain stem and spinal cord. Here, we review and discuss the current understanding of POMC neurons from their development and intracellular regulators to their physiological functions and pathological dysregulation.
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Affiliation(s)
- Chitoku Toda
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut 06520; .,Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Anna Santoro
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut 06520; .,Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Jung Dae Kim
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut 06520; .,Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Sabrina Diano
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, Connecticut 06520; .,Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut 06520.,Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06520.,Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut 06520
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Paeger L, Pippow A, Hess S, Paehler M, Klein AC, Husch A, Pouzat C, Brüning JC, Kloppenburg P. Energy imbalance alters Ca 2+ handling and excitability of POMC neurons. eLife 2017; 6. [PMID: 28762947 PMCID: PMC5538824 DOI: 10.7554/elife.25641] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 06/29/2017] [Indexed: 01/16/2023] Open
Abstract
Satiety-signaling, pro-opiomelanocortin (POMC)-expressing neurons in the arcuate nucleus of the hypothalamus play a pivotal role in the regulation of energy homeostasis. Recent studies reported altered mitochondrial dynamics and decreased mitochondria- endoplasmic reticulum contacts in POMC neurons during diet-induced obesity. Since mitochondria play a crucial role in Ca2+ signaling, we investigated whether obesity alters Ca2+ handling of these neurons in mice. In diet-induced obesity, cellular Ca2+ handling properties including mitochondrial Ca2+ uptake capacity are impaired, and an increased resting level of free intracellular Ca2+ is accompanied by a marked decrease in neuronal excitability. Experimentally increasing or decreasing intracellular Ca2+ concentrations reproduced electrophysiological properties observed in diet-induced obesity. Taken together, we provide the first direct evidence for a diet-dependent deterioration of Ca2+ homeostasis in POMC neurons during obesity development resulting in impaired function of these critical energy homeostasis-regulating neurons. DOI:http://dx.doi.org/10.7554/eLife.25641.001
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Affiliation(s)
- Lars Paeger
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Andreas Pippow
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Simon Hess
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Moritz Paehler
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Andreas C Klein
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Andreas Husch
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
| | - Christophe Pouzat
- MAP5 - Mathématiques Appliquées à Paris 5, CNRS UMR 8145, Paris, France
| | - Jens C Brüning
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany.,Department of Mouse Genetics and Metabolism, Institute for Genetics, Center of Molecular Medicine Cologne, Center for Endocrinology, Diabetes and Preventive Medicine, University Hospital of Cologne, Cologne, Germany.,Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Peter Kloppenburg
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany
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39
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Paeger L, Karakasilioti I, Altmüller J, Frommolt P, Brüning J, Kloppenburg P. Antagonistic modulation of NPY/AgRP and POMC neurons in the arcuate nucleus by noradrenalin. eLife 2017. [PMID: 28632132 PMCID: PMC5478265 DOI: 10.7554/elife.25770] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In the arcuate nucleus of the hypothalamus (ARH) satiety signaling (anorexigenic) pro-opiomelanocortin (POMC)-expressing and hunger signaling (orexigenic) agouti-related peptide (AgRP)-expressing neurons are key components of the neuronal circuits that control food intake and energy homeostasis. Here, we assessed whether the catecholamine noradrenalin directly modulates the activity of these neurons in mice. Perforated patch clamp recordings showed that noradrenalin changes the activity of these functionally antagonistic neurons in opposite ways, increasing the activity of the orexigenic NPY/AgRP neurons and decreasing the activity of the anorexigenic POMC neurons. Cell type-specific transcriptomics and pharmacological experiments revealed that the opposing effect on these neurons is mediated by the activation of excitatory α1A - and β- adrenergic receptors in NPY/AgRP neurons, while POMC neurons are inhibited via α2A – adrenergic receptors. Thus, the coordinated differential modulation of the key hypothalamic neurons in control of energy homeostasis assigns noradrenalin an important role to promote feeding. DOI:http://dx.doi.org/10.7554/eLife.25770.001
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Affiliation(s)
- Lars Paeger
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases, Cologne, Germany
| | - Ismene Karakasilioti
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases, Cologne, Germany.,Max Planck Institute for Metabolism Research, Cologne, Germany.,Center of Molecular Medicine Cologne, University of Cologne, Cologne, Germany.,Center for Endocrinology, Diabetes and Preventive Medicine, University Hospital Cologne, Cologne, Germany
| | - Janine Altmüller
- Center of Molecular Medicine Cologne, University of Cologne, Cologne, Germany.,Cologne Center for Genomics, University of Cologne, Cologne, Germany
| | - Peter Frommolt
- Bioinformatics Facility, Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases, Cologne, Germany
| | - Jens Brüning
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases, Cologne, Germany.,Max Planck Institute for Metabolism Research, Cologne, Germany.,Center of Molecular Medicine Cologne, University of Cologne, Cologne, Germany.,Center for Endocrinology, Diabetes and Preventive Medicine, University Hospital Cologne, Cologne, Germany
| | - Peter Kloppenburg
- Biocenter, Institute for Zoology, University of Cologne, Cologne, Germany.,Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases, Cologne, Germany
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40
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Dadak S, Beall C, Vlachaki Walker JM, Soutar MPM, McCrimmon RJ, Ashford MLJ. Oleate induces K ATP channel-dependent hyperpolarization in mouse hypothalamic glucose-excited neurons without altering cellular energy charge. Neuroscience 2017; 346:29-42. [PMID: 28087336 PMCID: PMC5346158 DOI: 10.1016/j.neuroscience.2016.12.053] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 12/29/2016] [Indexed: 11/29/2022]
Abstract
Oleate and low glucose hyperpolarize and inhibit GT1-7 and mouse GE neurons by activation of KATP. Oleate inhibition of GT1-7 neuron activity is not mediated by AMPK or fatty acid oxidation. Activation of KATP by oleate requires ATP hydrolysis but does not reduce the levels ATP or the ATP:ADP ratio. GT1-7 hyperpolarization by oleate is not dependent on UCP2. Oleate and low glucose depolarize a subpopulation of hypothalamic GI neurons.
The unsaturated fatty acid, oleate exhibits anorexigenic properties reducing food intake and hepatic glucose output. However, its mechanism of action in the hypothalamus has not been fully determined. This study investigated the effects of oleate and glucose on GT1-7 mouse hypothalamic cells (a model of glucose-excited (GE) neurons) and mouse arcuate nucleus (ARC) neurons. Whole-cell and perforated patch-clamp recordings, immunoblotting and cell energy status measures were used to investigate oleate- and glucose-sensing properties of mouse hypothalamic neurons. Oleate or lowered glucose concentration caused hyperpolarization and inhibition of firing of GT1-7 cells by the activation of ATP-sensitive K+ channels (KATP). This effect of oleate was not dependent on fatty acid oxidation or raised AMP-activated protein kinase activity or prevented by the presence of the UCP2 inhibitor genipin. Oleate did not alter intracellular calcium, indicating that CD36/fatty acid translocase may not play a role. However, oleate activation of KATP may require ATP metabolism. The short-chain fatty acid octanoate was unable to replicate the actions of oleate on GT1-7 cells. Although oleate decreased GT1-7 cell mitochondrial membrane potential there was no change in total cellular ATP or ATP/ADP ratios. Perforated patch and whole-cell recordings from mouse hypothalamic slices demonstrated that oleate hyperpolarized a subpopulation of ARC GE neurons by KATP activation. Additionally, in a separate small population of ARC neurons, oleate application or lowered glucose concentration caused membrane depolarization. In conclusion, oleate induces KATP-dependent hyperpolarization and inhibition of firing of a subgroup of GE hypothalamic neurons without altering cellular energy charge.
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Affiliation(s)
- Selma Dadak
- Division of Molecular and Clinical Medicine, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - Craig Beall
- Division of Molecular and Clinical Medicine, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK; Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, RILD Building, Barrack Road, Exeter EX2 5DW, UK
| | - Julia M Vlachaki Walker
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, RILD Building, Barrack Road, Exeter EX2 5DW, UK
| | - Marc P M Soutar
- Division of Molecular and Clinical Medicine, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - Rory J McCrimmon
- Division of Molecular and Clinical Medicine, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - Michael L J Ashford
- Division of Molecular and Clinical Medicine, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK.
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41
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Hofmann K, Lamberz C, Piotrowitz K, Offermann N, But D, Scheller A, Al-Amoudi A, Kuerschner L. Tanycytes and a differential fatty acid metabolism in the hypothalamus. Glia 2016; 65:231-249. [PMID: 27726181 DOI: 10.1002/glia.23088] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 08/31/2016] [Accepted: 09/28/2016] [Indexed: 11/12/2022]
Abstract
Although the brain controls all main metabolic pathways in the whole organism, its lipid metabolism is partially separated from the rest of the body. Circulating lipids and other metabolites are taken up into brain areas like the hypothalamus and are locally metabolized and sensed involving several hypothalamic cell types. In this study we show that saturated and unsaturated fatty acids are differentially processed in the murine hypothalamus. The observed differences involve both lipid distribution and metabolism. Key findings were: (i) hypothalamic astrocytes are targeted by unsaturated, but not saturated lipids in lean mice; (ii) in obese mice labeling of these astrocytes by unsaturated oleic acid cannot be detected unless β-oxidation or ketogenesis is inhibited; (iii) the hypothalamus of obese animals increases ketone body and neutral lipid synthesis while tanycytes, hypothalamic cells facing the ventricle, increase their lipid droplet content; and (iv) tanycytes show different labeling for saturated or unsaturated lipids. Our data support a metabolic connection between tanycytes and astrocytes likely to impact hypothalamic lipid sensing. GLIA 2017;65:231-249.
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Affiliation(s)
- Kristina Hofmann
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
| | - Christian Lamberz
- German Center for Neurodegenerative Diseases (DZNE), Bonn, D-53175, Germany
| | - Kira Piotrowitz
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
| | - Nina Offermann
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
| | - Diana But
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
| | - Anja Scheller
- Department of Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, D-66421, Germany
| | - Ashraf Al-Amoudi
- German Center for Neurodegenerative Diseases (DZNE), Bonn, D-53175, Germany
| | - Lars Kuerschner
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
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42
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Muroi Y, Ishii T. A novel neuropeptide Y neuronal pathway linking energy state and reproductive behavior. Neuropeptides 2016; 59:1-8. [PMID: 27659234 DOI: 10.1016/j.npep.2016.09.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/08/2016] [Accepted: 09/08/2016] [Indexed: 01/12/2023]
Abstract
Animals consume energy for reproduction, as well as survival. Excess or insufficient energy investment into reproduction, respectively, threatens the survival of parents or leads to the failure of reproduction. Management of energy consumption in reproduction is important, not only for the success of the process, but also for the survival of the parents. Reproductive behaviors, such as mating and parental behavior, are indispensable for achieving each event of reproduction including gametogamy, parturition, and lactation. Therefore, reproductive behavior is one of the important factors in managing energy consumption for reproduction. Orexigenic and anorexigenic molecules in the hypothalamus have been implicated in the regulation of reproductive functions. An orexigenic neuropeptide, neuropeptide Y (NPY), has been also implicated in the regulation of both reproduction and energy state of animals. In this review, we will first summarize the neuronal mechanism for regulating reproductive functions by orexigenic and anorexigenic molecules in the hypothalamus. Second, we will focus on the NPY neuronal pathways regulating reproductive behavior in the intra- and extra-hypothalamic brain areas. We will highlight the NPY neuronal pathway from the arcuate nucleus to the dorsal raphe nucleus as a novel extra-hypothalamic pathway for energy state-dependent regulation of reproductive behavior. Finally, we will propose a biological significance of the extra-hypothalamic NPY neuronal pathway, which plays an important role in the associative control of feeding and reproductive behaviors.
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Affiliation(s)
- Yoshikage Muroi
- Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
| | - Toshiaki Ishii
- Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
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Oh YT, Oh HH, Nguyen AK, Choi CS, Youn JH. Circulating free fatty acids inhibit food intake in an oleate-specific manner in rats. Physiol Behav 2016; 167:194-201. [PMID: 27654062 DOI: 10.1016/j.physbeh.2016.09.015] [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: 07/14/2016] [Revised: 08/31/2016] [Accepted: 09/14/2016] [Indexed: 10/21/2022]
Abstract
Previous rodent studies showed that when injected into the brain, free fatty acids (FFAs) reduced food intake in an oleate-specific manner. The present study was performed to test whether food intake is regulated by circulating FFAs in an oleate-specific manner. Male Wistar rats received an intravenous infusion of olive, safflower, or coconut oil (100mg/h), together with heparin, to raise circulating oleate, linoleate, or palmitate, respectively, and their effects on overnight food intake were evaluated. Compared to other oils, olive oil infusion showed a significantly greater effect to reduce food intake (P<0.01). Total caloric intake, the sum of the calories from the diet and infused oil, was significantly reduced with olive oil (P<0.01) but not with coconut or safflower oil infusion, suggesting an oleate-specific effect on caloric intake. To further test this idea, different groups of rats received an intravenous infusion of oleate, linoleate, or octanoate (0.5mg/h). Oleate infusion decreased overnight food intake by 26% (P<0.001), but no significant effect was seen with linoleate, octanoate, or vehicle infusion (P>0.05). The effects of olive oil or oleate infusion could not be explained by changes in plasma glucose, insulin, leptin, or total FFA levels. The olive oil effect on food intake was not reduced in vagotomized rats, suggesting that oleate sensing may not involve peripheral sensors. In contrast, olive oil's effect was attenuated in high-fat-fed rats, suggesting that this effect is regulated (or impaired) under physiological (or pathological) conditions. Taken together, the present study provides evidence that circulating oleate is sensed by the brain differentially from other FFAs to control feeding in rats.
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Affiliation(s)
- Young Taek Oh
- Department of Physiology and Biophysics, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - Hyun Hee Oh
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University School of Medicine, Incheon, Republic of Korea
| | - Anh-Khoi Nguyen
- Department of Exercise Sciences, University of Southern California, Los Angeles, CA, USA
| | - Cheol Soo Choi
- Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University School of Medicine, Incheon, Republic of Korea
| | - Jang H Youn
- Department of Physiology and Biophysics, University of Southern California Keck School of Medicine, Los Angeles, CA, USA.
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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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45
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Stark R, Reichenbach A, Andrews ZB. Hypothalamic carnitine metabolism integrates nutrient and hormonal feedback to regulate energy homeostasis. Mol Cell Endocrinol 2015; 418 Pt 1:9-16. [PMID: 26261054 DOI: 10.1016/j.mce.2015.08.002] [Citation(s) in RCA: 19] [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: 05/23/2015] [Revised: 07/31/2015] [Accepted: 08/03/2015] [Indexed: 01/11/2023]
Abstract
The maintenance of energy homeostasis requires the hypothalamic integration of nutrient feedback cues, such as glucose, fatty acids, amino acids, and metabolic hormones such as insulin, leptin and ghrelin. Although hypothalamic neurons are critical to maintain energy homeostasis research efforts have focused on feedback mechanisms in isolation, such as glucose alone, fatty acids alone or single hormones. However this seems rather too simplistic considering the range of nutrient and endocrine changes associated with different metabolic states, such as starvation (negative energy balance) or diet-induced obesity (positive energy balance). In order to understand how neurons integrate multiple nutrient or hormonal signals, we need to identify and examine potential intracellular convergence points or common molecular targets that have the ability to sense glucose, fatty acids, amino acids and hormones. In this review, we focus on the role of carnitine metabolism in neurons regulating energy homeostasis. Hypothalamic carnitine metabolism represents a novel means for neurons to facilitate and control both nutrient and hormonal feedback. In terms of nutrient regulation, carnitine metabolism regulates hypothalamic fatty acid sensing through the actions of CPT1 and has an underappreciated role in glucose sensing since carnitine metabolism also buffers mitochondrial matrix levels of acetyl-CoA, an allosteric inhibitor of pyruvate dehydrogenase and hence glucose metabolism. Studies also show that hypothalamic CPT1 activity also controls hormonal feedback. We hypothesis that hypothalamic carnitine metabolism represents a key molecular target that can concurrently integrate nutrient and hormonal information, which is critical to maintain energy homeostasis. We also suggest this is relevant to broader neuroendocrine research as it predicts that hormonal signaling in the brain varies depending on current nutrient status. Indeed, the metabolic action of ghrelin, leptin or insulin at POMC or NPY neurons may depend on appropriate nutrient-sensing in these neurons and we hypothesize carnitine metabolism is critical in the integrative processing. Future research is required to examine the neuron-specific effects of carnitine metabolism on concurrent nutrient- and hormonal-sensing in AgRP and POMC neurons.
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Affiliation(s)
- Romana Stark
- Department of Physiology, Monash University, Clayton, Victoria 3183, Australia
| | - Alex Reichenbach
- Department of Physiology, Monash University, Clayton, Victoria 3183, Australia
| | - Zane B Andrews
- Department of Physiology, Monash University, Clayton, Victoria 3183, Australia.
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Magnan C, Levin BE, Luquet S. Brain lipid sensing and the neural control of energy balance. Mol Cell Endocrinol 2015; 418 Pt 1:3-8. [PMID: 26415589 DOI: 10.1016/j.mce.2015.09.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 09/14/2015] [Accepted: 09/22/2015] [Indexed: 12/29/2022]
Abstract
Fatty acid (FA) -sensitive neurons are present in the brain, especially the hypothalamus, and play a key role in the neural control of energy and glucose homeostasis including feeding behavior, secretion insulin and action. Subpopulations of neurons in the arcuate and ventromedial hypothalamic nuclei are selectively either activated or inhibited by FA. Molecular effectors of these FA effects include ion channels such as chloride, potassium or calcium. In addition, at least half of the responses in the hypothalamic ventromedial FA neurons are mediated through interaction with the FA translocator/receptor, FAT/CD36, that does not require metabolism to activate intracellular signaling downstream. Recently, an important role of lipoprotein lipase in FA detection has also been demonstrated not only in the hypothalamus, but also in the hippocampus and striatum. Finally, FA could overload energy homeostasis via increased hypothalamic ceramide synthesis which could, in turn, contribute to the pathogenesis of diabetes of obesity and/or type 2 in predisposed individuals by disrupting the endocrine signaling pathways of insulin and/or leptin.
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Affiliation(s)
- Christophe Magnan
- Univ Paris Diderot, Sorbonne Paris Cité, CNRS UMR 8251, F-75205, Paris, France.
| | - Barry E Levin
- Neurology Service, VA Medical Center, East Orange, NJ, USA; Department of Neurology, Rutgers, NJ Medical School, Newark, NJ, USA
| | - Serge Luquet
- Univ Paris Diderot, Sorbonne Paris Cité, CNRS UMR 8251, F-75205, Paris, France
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Poon K, Alam M, Karatayev O, Barson JR, Leibowitz SF. Regulation of the orexigenic neuropeptide, enkephalin, by PPARδ and fatty acids in neurons of the hypothalamus and forebrain. J Neurochem 2015; 135:918-31. [PMID: 26332891 DOI: 10.1111/jnc.13298] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 07/28/2015] [Accepted: 08/23/2015] [Indexed: 11/28/2022]
Abstract
Ingestion of a high-fat diet composed mainly of the saturated fatty acid, palmitic (PA), and the unsaturated fatty acid, oleic (OA), stimulates transcription in the brain of the opioid neuropeptide, enkephalin (ENK), which promotes intake of substances of abuse. To understand possible underlying mechanisms, this study examined the nuclear receptors, peroxisome proliferator-activated receptors (PPARs), and tested in hypothalamic and forebrain neurons from rat embryos whether PPARs regulate endogenous ENK and the fatty acids themselves affect these PPARs and ENK. The first set of experiments demonstrated that knocking down PPARδ, but not PPARα or PPARγ, increased ENK transcription, activation of PPARδ by an agonist decreased ENK levels, and PPARδ neurons coexpressed ENK, suggesting that PPARδ negatively regulates ENK. In the second set of experiments, PA treatment of hypothalamic and forebrain neurons had no effect on PPARδ protein while stimulating ENK mRNA and protein, whereas OA increased both mRNA and protein levels of PPARδ in forebrain neurons while having no effect on ENK mRNA and increasing ENK levels. These findings show that PA has a strong, stimulatory effect on ENK and weak effect on PPARδ protein, whereas OA has a strong stimulatory effect on PPARδ and weak effect on ENK, consistent with the inhibitory effect of PPARδ on ENK. They suggest a function for PPARδ, perhaps protective in nature, in embryonic neurons exposed to fatty acids from a fat-rich diet and provide evidence for a mechanism contributing to differential effects of saturated and monounsaturated fatty acids on neurochemical systems involved in consummatory behavior. Our findings show that PPARδ in forebrain and hypothalamic neurons negatively regulates enkephalin (ENK), a peptide known to promote ingestive behavior. This inverse relationship is consistent with our additional findings, that a saturated (palmitic; PA) compared to a monounsaturated fatty acid (oleic; OA) has a strong stimulatory effect on ENK and weak effect on PPARδ. These results suggest that PPARδ protects against the neuronal effects of fatty acids, which differentially affect neurochemical systems involved in ingestive behavior.
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Affiliation(s)
- Kinning Poon
- Laboratory of Behavioral Neurobiology, The Rockefeller University, New York City, New York, USA
| | - Mohammad Alam
- Laboratory of Behavioral Neurobiology, The Rockefeller University, New York City, New York, USA
| | - Olga Karatayev
- Laboratory of Behavioral Neurobiology, The Rockefeller University, New York City, New York, USA
| | - Jessica R Barson
- Laboratory of Behavioral Neurobiology, The Rockefeller University, New York City, New York, USA
| | - Sarah F Leibowitz
- Laboratory of Behavioral Neurobiology, The Rockefeller University, New York City, New York, USA
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Abstract
The ability to "see" both incoming and circulating nutrients plays an essential role in the maintenance of energy homeostasis. As such, nutrient-sensing mechanisms in both the gastrointestinal tract and the brain have been implicated in the regulation of energy intake and glucose homeostasis. The intestinal wall is able to differentiate individual nutrients through sensory machinery expressed in the mucosa and provide feedback signals, via local gut peptide action, to maintain energy balance. Furthermore, both the hypothalamus and hindbrain detect circulating nutrients and respond by controlling energy intake and glucose levels. Conversely, nutrient sensing in the intestine plays a role in stimulating food intake and preferences. In this review, we highlight the emerging evidence for the regulation of energy balance through nutrient-sensing mechanisms in the intestine and the brain, and how disruption of these pathways could result in the development of obesity and type 2 diabetes.
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Affiliation(s)
- Sophie C Hamr
- Department of Physiology, University of Toronto, Toronto, M5S 1A8, Canada,
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49
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Moullé VS, Picard A, Cansell C, Luquet S, Magnan C. Rôle de la détection centrale des lipides dans le contrôle nerveux de la balance énergétique. Med Sci (Paris) 2015; 31:397-403. [DOI: 10.1051/medsci/20153104014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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50
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Wellhauser L, Gojska NM, Belsham DD. Delineating the regulation of energy homeostasis using hypothalamic cell models. Front Neuroendocrinol 2015; 36:130-49. [PMID: 25223866 DOI: 10.1016/j.yfrne.2014.09.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 08/28/2014] [Accepted: 09/02/2014] [Indexed: 12/27/2022]
Abstract
Attesting to its intimate peripheral connections, hypothalamic neurons integrate nutritional and hormonal cues to effectively manage energy homeostasis according to the overall status of the system. Extensive progress in the identification of essential transcriptional and post-translational mechanisms regulating the controlled expression and actions of hypothalamic neuropeptides has been identified through the use of animal and cell models. This review will introduce the basic techniques of hypothalamic investigation both in vivo and in vitro and will briefly highlight the key advantages and challenges of their use. Further emphasis will be place on the use of immortalized models of hypothalamic neurons for in vitro study of feeding regulation, with a particular focus on cell lines proving themselves most fruitful in deciphering fundamental basics of NPY/AgRP, Proglucagon, and POMC neuropeptide function.
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Affiliation(s)
- Leigh Wellhauser
- Department of Physiology, University of Toronto, Toronto, Ontario M5G 1A8, Canada
| | - Nicole M Gojska
- Department of Physiology, University of Toronto, Toronto, Ontario M5G 1A8, Canada
| | - Denise D Belsham
- Departments of Physiology, Medicine and OB/GYN, University of Toronto, Toronto, Ontario M5G 1A8, Canada; Division of Cellular and Molecular Biology, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario M5S 1A8, Canada.
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