1
|
Dali R, Estrada-Meza J, Langlet F. Tanycyte, the neuron whisperer. Physiol Behav 2023; 263:114108. [PMID: 36740135 DOI: 10.1016/j.physbeh.2023.114108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/23/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023]
Abstract
Reciprocal communication between neurons and glia is essential for normal brain functioning and adequate physiological functions, including energy balance. In vertebrates, the homeostatic process that adjusts food intake and energy expenditure in line with physiological requirements is tightly controlled by numerous neural cell types located within the hypothalamus and the brainstem and organized in complex networks. Within these neural networks, peculiar ependymoglial cells called tanycytes are nowadays recognized as multifunctional players in the physiological mechanisms of appetite control, partly by modulating orexigenic and anorexigenic neurons. Here, we review recent advances in tanycytes' impact on hypothalamic neuronal activity, emphasizing on arcuate neurons.
Collapse
Affiliation(s)
- Rafik Dali
- Department of biomedical sciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Judith Estrada-Meza
- Department of biomedical sciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Fanny Langlet
- Department of biomedical sciences, University of Lausanne, 1005 Lausanne, Switzerland.
| |
Collapse
|
2
|
Lopez-Rodriguez D, Rohrbach A, Lanzillo M, Gervais M, Croizier S, Langlet F. Ontogeny of ependymoglial cells lining the third ventricle in mice. Front Endocrinol (Lausanne) 2023; 13:1073759. [PMID: 36686420 PMCID: PMC9849764 DOI: 10.3389/fendo.2022.1073759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 12/02/2022] [Indexed: 01/07/2023] Open
Abstract
Introduction During hypothalamic development, the germinative neuroepithelium gives birth to diverse neural cells that regulate numerous physiological functions in adulthood. Methods Here, we studied the ontogeny of ependymal cells in the mouse mediobasal hypothalamus using the BrdU approach and publicly available single-cell RNAseq datasets. Results We observed that while typical ependymal cells are mainly produced at E13, tanycyte birth depends on time and subtypes and lasts up to P8. Typical ependymocytes and β tanycytes are the first to arise at the top and bottom of the dorsoventral axis around E13, whereas α tanycytes emerge later in development, generating an outside-in dorsoventral gradient along the third ventricle. Additionally, α tanycyte generation displayed a rostral-to-caudal pattern. Finally, tanycytes mature progressively until they reach transcriptional maturity between P4 and P14. Discussion Altogether, this data shows that ependyma generation differs in time and distribution, highlighting the heterogeneity of the third ventricle.
Collapse
Affiliation(s)
- David Lopez-Rodriguez
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Antoine Rohrbach
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Marc Lanzillo
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Manon Gervais
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Sophie Croizier
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Fanny Langlet
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
3
|
Barahona MJ, Langlet F, Labouèbe G, Croizier S, Picard A, Thorens B, García-Robles MA. GLUT2 expression by glial fibrillary acidic protein-positive tanycytes is required for promoting feeding-response to fasting. Sci Rep 2022; 12:17717. [PMID: 36271117 PMCID: PMC9587252 DOI: 10.1038/s41598-022-22489-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 10/14/2022] [Indexed: 01/18/2023] Open
Abstract
Feeding behavior is a complex process that depends on the ability of the brain to integrate hormonal and nutritional signals, such as glucose. One glucosensing mechanism relies on the glucose transporter 2 (GLUT2) in the hypothalamus, especially in radial glia-like cells called tanycytes. Here, we analyzed whether a GLUT2-dependent glucosensing mechanism is required for the normal regulation of feeding behavior in GFAP-positive tanycytes. Genetic inactivation of Glut2 in GFAP-expressing tanycytes was performed using Cre/Lox technology. The efficiency of GFAP-tanycyte targeting was analyzed in the anteroposterior and dorsoventral axes by evaluating GFP fluorescence. Feeding behavior, hormonal levels, neuronal activity using c-Fos, and neuropeptide expression were also analyzed in the fasting-to-refeeding transition. In basal conditions, Glut2-inactivated mice had normal food intake and meal patterns. Implementation of a preceeding fasting period led to decreased total food intake and a delay in meal initiation during refeeding. Additionally, Glut2 inactivation increased the number of c-Fos-positive cells in the ventromedial nucleus in response to fasting and a deregulation of Pomc expression in the fasting-to-refeeding transition. Thus, a GLUT2-dependent glucose-sensing mechanism in GFAP-tanycytes is required to control food consumption and promote meal initiation after a fasting period.
Collapse
Affiliation(s)
- M. J. Barahona
- grid.5380.e0000 0001 2298 9663Laboratorio de Biología Celular, Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile ,grid.5380.e0000 0001 2298 9663Present Address: Laboratorio de Neurobiología y células madres (NeuroCellT), Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - F. Langlet
- grid.9851.50000 0001 2165 4204Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland ,grid.9851.50000 0001 2165 4204Present Address: Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - G. Labouèbe
- grid.9851.50000 0001 2165 4204Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - S. Croizier
- grid.9851.50000 0001 2165 4204Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - A. Picard
- grid.9851.50000 0001 2165 4204Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Bernard Thorens
- grid.9851.50000 0001 2165 4204Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - María A. García-Robles
- grid.5380.e0000 0001 2298 9663Laboratorio de Biología Celular, Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile ,grid.412185.b0000 0000 8912 4050Instituto de Neurociencias, Centro Interdisciplinario de Neurociencias de Valparaíso, Universidad de Valparaíso, Valparaiso, Chile
| |
Collapse
|
4
|
Rohrbach A, Caron E, Dali R, Brunner M, Pasquettaz R, Kolotuev I, Santoni F, Thorens B, Langlet F. Ablation of glucokinase-expressing tanycytes impacts energy balance and increases adiposity in mice. Mol Metab 2021; 53:101311. [PMID: 34325016 PMCID: PMC8379510 DOI: 10.1016/j.molmet.2021.101311] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 07/20/2021] [Indexed: 01/06/2023] Open
Abstract
Objectives Glucokinase (GCK) is critical for glucosensing. In rats, GCK is expressed in hypothalamic tanycytes and appears to play an essential role in feeding behavior. In this study, we investigated the distribution of GCK-expressing tanycytes in mice and their role in the regulation of energy balance. Methods In situ hybridization, reporter gene assay, and immunohistochemistry were used to assess GCK expression along the third ventricle in mice. To evaluate the impact of GCK-expressing tanycytes on arcuate neuron function and mouse physiology, Gck deletion along the ventricle was achieved using loxP/Cre recombinase technology in adult mice. Results GCK expression was low along the third ventricle, but detectable in tanycytes facing the ventromedial arcuate nucleus from bregma −1.5 to −2.2. Gck deletion induced the death of this tanycyte subgroup through the activation of the BAD signaling pathway. The ablation of GCK-expressing tanycytes affected different aspects of energy balance, leading to an increase in adiposity in mice. This phenotype was systematically associated with a defect in NPY neuron function. In contrast, the regulation of glucose homeostasis was mostly preserved, except for glucoprivic responses. Conclusions This study describes the role of GCK in tanycyte biology and highlights the impact of tanycyte loss on the regulation of energy balance. vmARH tanycytes express glucokinase. Glucokinase deletion in tanycytes induces cell death. Ablation of vmARH tanycytes alters energy balance and adiposity. Ablation of vmARH tanycytes alters NPY neuron function.
Collapse
Affiliation(s)
- Antoine Rohrbach
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland; Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Emilie Caron
- Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S, 1172, Lille, France
| | - Rafik Dali
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Maxime Brunner
- Service of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital, Faculty of Biology and Medicine, 1011, Lausanne, Switzerland
| | - Roxane Pasquettaz
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Irina Kolotuev
- Electron Microscopy Facility, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Federico Santoni
- Service of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital, Faculty of Biology and Medicine, 1011, Lausanne, Switzerland
| | - Bernard Thorens
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Fanny Langlet
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland; Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.
| |
Collapse
|
5
|
Abstract
In vertebrates, the energy balance process is tightly controlled by complex neural circuits that sense metabolic signals and adjust food intake and energy expenditure in line with the physiological requirements of optimal conditions. Within neural networks controlling energy balance, tanycytes are peculiar ependymoglial cells that are nowadays recognized as multifunctional players in the metabolic hypothalamus. However, the physiological function of hypothalamic tanycytes remains unclear, creating a number of ambiguities in the field. Here, we review data accumulated over the years that demonstrate the physiological function of tanycytes in the maintenance of metabolic homeostasis, opening up new research avenues. The presumed involvement of tanycytes in the pathophysiology of metabolic disorders and age-related neurodegenerative diseases will be finally discussed.
Collapse
Affiliation(s)
- Matei Bolborea
- Central and Peripheral Mechanisms of Neurodegeneration, INSERM U1118, Université de Strasbourg, Strasbourg, France.,School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Fanny Langlet
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
6
|
Pasquettaz R, Kolotuev I, Rohrbach A, Gouelle C, Pellerin L, Langlet F. Peculiar protrusions along tanycyte processes face diverse neural and nonneural cell types in the hypothalamic parenchyma. J Comp Neurol 2020; 529:553-575. [PMID: 32515035 PMCID: PMC7818493 DOI: 10.1002/cne.24965] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 05/22/2020] [Accepted: 05/27/2020] [Indexed: 12/15/2022]
Abstract
Tanycytes are highly specialized ependymal cells that line the bottom and the lateral walls of the third ventricle. In contact with the cerebrospinal fluid through their cell bodies, they send processes into the arcuate nucleus, the ventromedial nucleus, and the dorsomedial nucleus of the hypothalamus. In the present work, we combined transgenic and immunohistochemical approaches to investigate the neuroanatomical associations between tanycytes and neural cells present in the hypothalamic parenchyma, in particular in the arcuate nucleus. The specific expression of tdTomato in tanycytes first allowed the observation of peculiar subcellular protrusions along tanycyte processes and at their endfeet such as spines, swelling, en passant boutons, boutons, or claws. Interestingly, these protrusions contact different neural cells in the brain parenchyma including blood vessels and neurons, and in particular NPY and POMC neurons in the arcuate nucleus. Using both fluorescent and electron microscopy, we finally observed that these tanycyte protrusions contain ribosomes, mitochondria, diverse vesicles, and transporters, suggesting dense tanycyte/neuron and tanycyte/blood vessel communications. Altogether, our results lay the neuroanatomical basis for tanycyte/neural cell interactions, which will be useful to further understand cell-to-cell communications involved in the regulation of neuroendocrine functions.
Collapse
Affiliation(s)
- Roxane Pasquettaz
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Irina Kolotuev
- Electron Microscopy Facility, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Antoine Rohrbach
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Cathy Gouelle
- Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Luc Pellerin
- Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.,Centre de Résonance Magnétique des Systèmes Biologiques, UMR5536 CNRS, LabEx TRAIL-IBIO, Université de Bordeaux, Bordeaux Cedex, France.,Inserm U1082, Universite de Poitiers, Poitiers Cedex, France
| | - Fanny Langlet
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
7
|
Abstract
Tanycytes are peculiar ependymoglial cells lining the bottom and the lateral wall of the third ventricle. For a decade, the utilization of molecular genetic approaches allowed us to make important discoveries about their diverse physiological functions. Here, I review the current methods used to target tanycytes, focusing on their specificity, their efficiency, their limitations, as well as their potential future improvements.
Collapse
Affiliation(s)
- Fanny Langlet
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland,
| |
Collapse
|
8
|
Langlet F, Sáez JC, García-Robles MA. Editorial: Involvement of Tanycytes in the Neuroendocrine Control of Energy Homeostasis. Front Endocrinol (Lausanne) 2020; 11:464. [PMID: 32793116 PMCID: PMC7387573 DOI: 10.3389/fendo.2020.00464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 06/15/2020] [Indexed: 11/15/2022] Open
Affiliation(s)
- Fanny Langlet
- Faculty of Biology and Medicine, Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Juan C. Sáez
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Centro Interdisciplinario de Neurociencias de Valparaíso, Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso, Chile
| | - María A. García-Robles
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
- *Correspondence: María A. García-Robles
| |
Collapse
|
9
|
Abstract
Animal survival relies on a constant balance between energy supply and energy expenditure, which is controlled by several neuroendocrine functions that integrate metabolic information and adapt the response of the organism to physiological demands. Polarized ependymoglial cells lining the floor of the third ventricle and sending a single process within metabolic hypothalamic parenchyma, tanycytes are henceforth described as key components of the hypothalamic neural network controlling energy balance. Their strategic position and peculiar properties convey them diverse physiological functions ranging from blood/brain traffic controllers, metabolic modulators, and neural stem/progenitor cells. At the molecular level, these functions rely on an accurate regulation of gene expression. Indeed, tanycytes are characterized by their own molecular signature which is mostly associated to their diverse physiological functions, and the detection of variations in nutrient/hormone levels leads to an adequate modulation of genetic profile in order to ensure energy homeostasis. The aim of this review is to summarize recent knowledge on the nutritional control of tanycyte gene expression.
Collapse
|
10
|
Langlet F, Tarbier M, Haeusler RA, Camastra S, Ferrannini E, Friedländer MR, Accili D. microRNA-205-5p is a modulator of insulin sensitivity that inhibits FOXO function. Mol Metab 2018; 17:49-60. [PMID: 30174230 PMCID: PMC6197154 DOI: 10.1016/j.molmet.2018.08.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Accepted: 08/07/2018] [Indexed: 12/20/2022] Open
Abstract
Objectives Hepatic insulin resistance is a hallmark of type 2 diabetes and obesity. Insulin receptor signaling through AKT and FOXO has important metabolic effects that have traditionally been ascribed to regulation of gene expression. However, whether all the metabolic effects of FOXO arise from its regulation of protein-encoding mRNAs is unknown. Methods To address this question, we obtained expression profiles of FOXO-regulated murine hepatic microRNAs (miRNAs) during fasting and refeeding using mice lacking Foxo1, 3a, and 4 in liver (L-Foxo1,3a, 4). Results Out of 439 miRNA analyzed, 175 were differentially expressed in Foxo knockouts. Their functions were associated with insulin, Wnt, Mapk signaling, and aging. Among them, we report a striking increase of miR-205-5p expression in L-Foxo1,3a,4 knockouts, as well as in obese mice. We show that miR-205-5p gain-of-function increases AKT phosphorylation and decreases SHIP2 in primary hepatocytes, resulting in FOXO inhibition. This results in decreased hepatocyte glucose production. Consistent with these observations, miR-205-5p gain-of-function in mice lowered glucose levels and improved pyruvate tolerance. Conclusions These findings reveal a homeostatic miRNA loop regulating insulin signaling, with potential implications for in vivo glucose metabolism. A comprehensive analysis of Foxo-dependent miRNA. miRNAs recapitulate the transcriptional effects of Foxo on insulin signaling. Foxo regulates miRNA transcription during the fasting/refeeding transition. miR205 regulates insulin sensitivity through a homeostatic loop with Foxo.
Collapse
Affiliation(s)
- Fanny Langlet
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, 10032, USA
| | - Marcel Tarbier
- Science for Life Laboratory, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 17121, Stockholm, Sweden
| | - Rebecca A Haeusler
- Naomi Berrie Diabetes Center and Departments of Pathology and Cell Biology, Columbia University, New York, 10032, USA
| | - Stefania Camastra
- Department of Clinical and Experimental Medicine, University of Pisa School of Medicine, Pisa, Italy
| | - Eleuterio Ferrannini
- Department of Clinical and Experimental Medicine, University of Pisa School of Medicine, Pisa, Italy; CNR Institute of Clinical Physiology, Pisa, Italy
| | - Marc R Friedländer
- Science for Life Laboratory, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 17121, Stockholm, Sweden
| | - Domenico Accili
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, 10032, USA.
| |
Collapse
|
11
|
Abstract
MicroRNAs are small non-coding RNAs that modulate gene expression post-transcriptionally. Discovered more than 15 years ago, their functions start to be unraveled. Increasing evidence points to an important functional role of microRNAs in brain development. In particular, miRNAs have recently been established to play a vital role in the mechanisms underlying the infantile rise in gonadotropin-releasing hormone (GnRH) production by neurons in the hypothalamus, a phenomenon necessary for the onset of puberty in mammals.
Collapse
Affiliation(s)
- Andrea Messina
- Service d'Endocrinologie, Diabétologie et Métabolisme, Hôpital universitaire de Lausanne, Lausanne, Suisse
| | - Fanny Langlet
- Columbia University Medical Center and Berrie Diabetes Center, New York, États-Unis
| | - Vincent Prevot
- Laboratoire de Développement et de Plasticité du Cerveau Neuroendocrine, FHU 1000 days for health, Inserm U1172, Université de Lille, Lille, France
| |
Collapse
|
12
|
Denis RGP, Joly-Amado A, Webber E, Langlet F, Schaeffer M, Padilla SL, Cansell C, Dehouck B, Castel J, Delbès AS, Martinez S, Lacombe A, Rouch C, Kassis N, Fehrentz JA, Martinez J, Verdié P, Hnasko TS, Palmiter RD, Krashes MJ, Güler AD, Magnan C, Luquet S. Palatability Can Drive Feeding Independent of AgRP Neurons. Cell Metab 2017; 25:975. [PMID: 28380385 DOI: 10.1016/j.cmet.2017.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
13
|
Messina A, Langlet F, Chachlaki K, Roa J, Rasika S, Jouy N, Gallet S, Gaytan F, Parkash J, Tena-Sempere M, Giacobini P, Prevot V. A microRNA switch regulates the rise in hypothalamic GnRH production before puberty. Nat Neurosci 2016; 19:835-44. [DOI: 10.1038/nn.4298] [Citation(s) in RCA: 140] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 04/01/2016] [Indexed: 12/12/2022]
|
14
|
Denis RGP, Joly-Amado A, Webber E, Langlet F, Schaeffer M, Padilla SL, Cansell C, Dehouck B, Castel J, Delbès AS, Martinez S, Lacombe A, Rouch C, Kassis N, Fehrentz JA, Martinez J, Verdié P, Hnasko TS, Palmiter RD, Krashes MJ, Güler AD, Magnan C, Luquet S. Palatability Can Drive Feeding Independent of AgRP Neurons. Cell Metab 2015; 22:646-57. [PMID: 26278050 PMCID: PMC5024566 DOI: 10.1016/j.cmet.2015.07.011] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 06/03/2015] [Accepted: 07/17/2015] [Indexed: 01/20/2023]
Abstract
Feeding behavior is exquisitely regulated by homeostatic and hedonic neural substrates that integrate energy demand as well as the reinforcing and rewarding aspects of food. Understanding the net contribution of homeostatic and reward-driven feeding has become critical because of the ubiquitous source of energy-dense foods and the consequent obesity epidemic. Hypothalamic agouti-related peptide-secreting neurons (AgRP neurons) provide the primary orexigenic drive of homeostatic feeding. Using models of neuronal inhibition or ablation, we demonstrate that the feeding response to a fast ghrelin or serotonin receptor agonist relies on AgRP neurons. However, when palatable food is provided, AgRP neurons are dispensable for an appropriate feeding response. In addition, AgRP-ablated mice present exacerbated stress-induced anorexia and palatable food intake--a hallmark of comfort feeding. These results suggest that, when AgRP neuron activity is impaired, neural circuits sensitive to emotion and stress are engaged and modulated by food palatability and dopamine signaling.
Collapse
Affiliation(s)
- Raphaël G P Denis
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Aurélie Joly-Amado
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Emily Webber
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1453, USA; National Institute of Drug Abuse, Baltimore, MD 21224, USA
| | - Fanny Langlet
- Institut national de la santé et de la recherche médicale, Jean-Pierre Aubert Research Center, U837, 59000 Lille, France; Faculté de Médecine, Université droit et santé de Lille, 59000 Lille, France
| | - Marie Schaeffer
- Centre National la Recherche Scientifique, Unité Mixte de Recherche 5203, Institut de Génomique Fonctionnelle, 34000 Montpellier, France; Institut national de la santé et de la recherche médicale, U661, 34000 Montpellier, France; Unité Mixte de Recherche 5203, University of Montpellier, 34000 Montpellier, France
| | - Stéphanie L Padilla
- Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA; Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Céline Cansell
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Bénédicte Dehouck
- Institut national de la santé et de la recherche médicale, Jean-Pierre Aubert Research Center, U837, 59000 Lille, France; Faculté de Médecine, Université droit et santé de Lille, 59000 Lille, France
| | - Julien Castel
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Anne-Sophie Delbès
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Sarah Martinez
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Amélie Lacombe
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Claude Rouch
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Nadim Kassis
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Jean-Alain Fehrentz
- Centre National la Recherche Scientifique, Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Ecole Nationale Supérieure de Chimie de Montpellier, Université Montpellier, 34093 Montpellier Cedex 5, France
| | - Jean Martinez
- Centre National la Recherche Scientifique, Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Ecole Nationale Supérieure de Chimie de Montpellier, Université Montpellier, 34093 Montpellier Cedex 5, France
| | - Pascal Verdié
- Centre National la Recherche Scientifique, Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Ecole Nationale Supérieure de Chimie de Montpellier, Université Montpellier, 34093 Montpellier Cedex 5, France
| | - Thomas S Hnasko
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Richard D Palmiter
- Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA; Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Michael J Krashes
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1453, USA; National Institute of Drug Abuse, Baltimore, MD 21224, USA
| | - Ali D Güler
- Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA; Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Department of Biology, University of Virginia, Charlottesville, VA 22904-4328, USA
| | - Christophe Magnan
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Serge Luquet
- Unité de Biologie Fonctionnelle et Adaptative, Centre National la Recherche Scientifique, Unité Mixte de Recherche 8251, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France.
| |
Collapse
|
15
|
Abstract
The development of insulin resistance (IR) in the liver is a key pathophysiologic event in the development of type 2 diabetes. Although insulin loses its ability to suppress glucose production, it largely retains its capacity to drive lipogenesis. This selective IR results in the characteristic hyperglycemia and dyslipidemia of type 2 diabetes. The delineation of two branched pathways of insulin receptor (InsR) signaling to glucose versus triglyceride production, one through FoxO and the other through SREBP-1c, provides a mechanism to account for this pathophysiological abnormality. We tested the complementary hypothesis that selective IR arises due to different intrinsic sensitivities of glucose production versus de novo lipogenesis to insulin as a result of cell-autonomous down-regulation of InsR number in response to chronic hyperinsulinemia. We demonstrate in mouse primary hepatocytes that chronic hyperinsulinemia abrogates insulin's inhibition of glucose production, but not its stimulation of de novo lipogenesis. Using a competitive inhibitor of InsR, we show that there is a 4-fold difference between levels of InsR inhibition required to cause resistance of glucose production versus lipogenesis to the actions of insulin. Our data support a parsimonious model in which differential InsR activation underlies the selective IR of glucose production relative to lipogenesis, but both processes require signaling through Akt1/2.
Collapse
Affiliation(s)
- Joshua R Cook
- From the Department of Medicine, Columbia University, New York, New York 10032 and
| | - Fanny Langlet
- From the Department of Medicine, Columbia University, New York, New York 10032 and
| | - Yoshiaki Kido
- the Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Domenico Accili
- From the Department of Medicine, Columbia University, New York, New York 10032 and
| |
Collapse
|
16
|
Abstract
Information exchanges between the brain and the periphery are key stages in the regulation of various physiological functions. The mediobasal hypothalamus, which ensures a large part of these functions, must be permanently informed about the physiological state of the body to guarantee the maintaining of homeostasis. For that purpose, it possesses a peculiar blood-brain interface due to the presence of specialized glial cells called tanycytes. This review describes the organization of the blood-hypothalamus interface and characterizes the peculiar place of tanycytes within it, as well as their striking capacity to remodel their own interface in order to ensure the regulation of various physiological functions.
Collapse
Affiliation(s)
- Fanny Langlet
- Inserm, Centre de recherche Jean-Pierre Aubert, U837, Développement et plasticité du cerveau post-natal, 59000 Lille, France - Université de Lille, Faculté de médecine, Institut de Médecine Prédictive et de Recherche Thérapeutique, 59000 Lille, France
| |
Collapse
|
17
|
Abstract
The central regulation of energy balance relies on the ability of the brain to promptly and efficiently sense variations of metabolic state. To achieve this, circulating hormonal and metabolic signals have to cross the blood-brain interface, where unusual glial cells named tanycytes have been described to play a key role in this process. Tanycytes are specialised polarised ependymoglial cells that line the floor of the third ventricle and send a single process to contact hypothalamic neurones and blood vessels. Although their role in the regulation of energy balance via the modulation of neuronal activity or their chemosensitivity has been already described, recent studies ascribe a new function to tanycytes in the regulation of energy homeostasis as a result of their capacity to regulate the access of metabolic signals to the hypothalamus. This review discusses the peculiar place of tanycytes within the blood-hypothalamus interface, as well as a striking capacity to remodel their own interface to ensure an adaptive metabolic response to energy imbalances.
Collapse
Affiliation(s)
- F Langlet
- Inserm, Jean-Pierre Aubert Research Centre, U837, Development and Plasticity of the Postnatal Brain, Lille, France; UDSL, School of Medicine, Lille, France; Université de Lille, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| |
Collapse
|
18
|
|
19
|
Osterstock G, El Yandouzi T, Romanò N, Carmignac D, Langlet F, Coutry N, Guillou A, Schaeffer M, Chauvet N, Vanacker C, Galibert E, Dehouck B, Robinson ICAF, Prévot V, Mollard P, Plesnila N, Méry PF. Sustained alterations of hypothalamic tanycytes during posttraumatic hypopituitarism in male mice. Endocrinology 2014; 155:1887-98. [PMID: 24601879 DOI: 10.1210/en.2013-1336] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Traumatic brain injury is a leading cause of hypopituitarism, which compromises patients' recovery, quality of life, and life span. To date, there are no means other than standardized animal studies to provide insights into the mechanisms of posttraumatic hypopituitarism. We have found that GH levels were impaired after inducing a controlled cortical impact (CCI) in mice. Furthermore, GHRH stimulation enhanced GH to lower level in injured than in control or sham mice. Because many characteristics were unchanged in the pituitary glands of CCI mice, we looked for changes at the hypothalamic level. Hypertrophied astrocytes were seen both within the arcuate nucleus and the median eminence, two pivotal structures of the GH axis, spatially remote to the injury site. In the arcuate nucleus, GHRH neurons were unaltered. In the median eminence, injured mice exhibited unexpected alterations. First, the distributions of claudin-1 and zonula occludens-1 between tanycytes were disorganized, suggesting tight junction disruptions. Second, endogenous IgG was increased in the vicinity of the third ventricle, suggesting abnormal barrier properties after CCI. Third, intracerebroventricular injection of a fluorescent-dextran derivative highly stained the hypothalamic parenchyma only after CCI, demonstrating an increased permeability of the third ventricle edges. This alteration of the third ventricle might jeopardize the communication between the hypothalamus and the pituitary gland. In conclusion, the phenotype of CCI mice had similarities to the posttraumatic hypopituitarism seen in humans with intact pituitary gland and pituitary stalk. It is the first report of a pathological status in which tanycyte dysfunctions appear as a major acquired syndrome.
Collapse
Affiliation(s)
- Guillaume Osterstock
- INSERM Unité 661 (G.O., T.E.Y., N.Co., N.R., A.G., M.S., N.Ch., E.G., P.M., P.-F.M.), Centre National de la Recherche Scientifique Unité Mixte de Recherche 5203 (G.O., T.E.Y., N.R., N.Co., A.G., M.S., N.Ch., E.G., P.M., P.-F.M.), Institut de Génomique Fonctionelle, 34094 Montpellier, France; Université Montpellier 1, 2 (G.O., T.E.Y., N.R., N.Co., A.G., M.S., N.Ch., E.G., P.M., P.-F.M.), 34967 Montpellier, France; Division of Molecular Neuroendocrinology (D.C., I.C.A.F.R.), Medical Research Council National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, United Kingdom; Royal College of Surgeons in Ireland (G.O., T.E.Y., M.S., N.P.), Dublin 2, Ireland; INSERM Unité 837 (F.L., C.V., B.D., V.P.), Department of Development and Plasticity of the Postnatal Brain, Jean-Pierre Aubert Research Center, 59045 Lille, France; and University of Lille 2 (F.L., C.V., B.D., V.P.), 59000 Lille, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Giacobini P, Parkash J, Campagne C, Messina A, Casoni F, Vanacker C, Langlet F, Hobo B, Cagnoni G, Gallet S, Hanchate NK, Mazur D, Taniguchi M, Mazzone M, Verhaagen J, Ciofi P, Bouret SG, Tamagnone L, Prevot V. Brain endothelial cells control fertility through ovarian-steroid-dependent release of semaphorin 3A. PLoS Biol 2014; 12:e1001808. [PMID: 24618750 PMCID: PMC3949669 DOI: 10.1371/journal.pbio.1001808] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 01/30/2014] [Indexed: 11/25/2022] Open
Abstract
Endothelial-cell–derived Sema3A promotes axonal outgrowth and plasticity and thereby regulates neurohormone release in the adult rodent brain in response to the ovarian cycle. Neuropilin-1 (Nrp1) guides the development of the nervous and vascular systems, but its role in the mature brain remains to be explored. Here we report that the expression of the 65 kDa isoform of Sema3A, the ligand of Nrp1, by adult vascular endothelial cells, is regulated during the ovarian cycle and promotes axonal sprouting in hypothalamic neurons secreting gonadotropin-releasing hormone (GnRH), the neuropeptide controlling reproduction. Both the inhibition of Sema3A/Nrp1 signaling and the conditional deletion of Nrp1 in GnRH neurons counteract Sema3A-induced axonal sprouting. Furthermore, the localized intracerebral infusion of Nrp1- or Sema3A-neutralizing antibodies in vivo disrupts the ovarian cycle. Finally, the selective neutralization of endothelial-cell Sema3A signaling in adult Sema3aloxP/loxP mice by the intravenous injection of the recombinant TAT-Cre protein alters the amplitude of the preovulatory luteinizing hormone surge, likely by perturbing GnRH release into the hypothalamo-hypophyseal portal system. Our results identify a previously unknown function for 65 kDa Sema3A-Nrp1 signaling in the induction of axonal growth, and raise the possibility that endothelial cells actively participate in synaptic plasticity in specific functional domains of the adult central nervous system, thus controlling key physiological functions such as reproduction. In the developing embryo, endothelial cells release chemotropic signals such as Semaphorin 3A (Sema3A) that, upon activation of its receptor Neuropilin-1 (Nrp1), regulate neuronal migration and axon guidance. However, whether endothelial cells in the adult brain retain the ability to secrete molecules that influence neuronal function is unknown. Here we show in the adult brain of rodents that vascular endothelial cells release Sema3A and that the amount released is regulated by the ovulatory cycle. Sema3A, in turn, promotes the outgrowth of axons of hypothalamic neurons that express Neuropilin-1 towards the endothelial wall of portal blood vessels. These neurons release there the neuropeptide that controls reproduction: gonadotropin-releasing hormone (GnRH). Notably, this endothelial-cell-mediated sprouting of GnRH axons regulates neuropeptide release at a key stage of the estrous cycle, the proestrus, when the surge of GnRH triggers ovulation. Thus, by promoting GnRH axonal growth in the adult brain, Sema3A/Neuropilin-1 plays a pivotal role in orchestrating the central control of reproduction. Our results suggest a model in which vascular endothelial cells are dynamic signaling components that relay peripheral information to the brain to control key physiological functions, including species survival.
Collapse
Affiliation(s)
- Paolo Giacobini
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Jyoti Parkash
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Céline Campagne
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Andrea Messina
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Filippo Casoni
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Charlotte Vanacker
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Fanny Langlet
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Barbara Hobo
- Netherlands institute for Neuroscience, Amsterdam, The Netherlands
- Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Gabriella Cagnoni
- Candiolo Cancer Institute - FPO (IRCCS) and University of Torino, Department of Oncology, Candiolo, Italy
| | - Sarah Gallet
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Naresh Kumar Hanchate
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Danièle Mazur
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
| | - Masahiko Taniguchi
- Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Massimiliano Mazzone
- Versalius Research Center, VIB, Laboratory of Molecular Oncology and Angiogenesis, Leuven, Belgium
- KU Keuven, Versalius Research Center, Leuven, Belgium
| | - Joost Verhaagen
- Netherlands institute for Neuroscience, Amsterdam, The Netherlands
- Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Philippe Ciofi
- INSERM, Neurocentre Magendie, U862, Université de Bordeaux, Bordeaux, France
| | - Sébastien G. Bouret
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
- The Saban Research Institute, Childrens Hospital Los Angeles, University of Southern California, Los Angeles, California, United States of America
| | - Luca Tamagnone
- Candiolo Cancer Institute - FPO (IRCCS) and University of Torino, Department of Oncology, Candiolo, Italy
| | - Vincent Prevot
- INSERM, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France
- UDSL, School of Medicine, Place de Verdun, Lille, France
- Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
- * E-mail:
| |
Collapse
|
21
|
Langlet F, Mullier A, Bouret SG, Prevot V, Dehouck B. Tanycyte-like cells form a blood-cerebrospinal fluid barrier in the circumventricular organs of the mouse brain. J Comp Neurol 2013; 521:3389-405. [PMID: 23649873 PMCID: PMC3973970 DOI: 10.1002/cne.23355] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 04/15/2013] [Accepted: 04/25/2013] [Indexed: 11/07/2022]
Abstract
Tanycytes are highly specialized ependymal cells that form a blood-cerebrospinal fluid (CSF) barrier at the level of the median eminence (ME), a circumventricular organ (CVO) located in the tuberal region of the hypothalamus. This ependymal layer harbors well-organized tight junctions, a hallmark of central nervous system barriers that is lacking in the fenestrated portal vessels of the ME. The displacement of barrier properties from the vascular to the ventricular side allows the diffusion of blood-borne molecules into the parenchyma of the ME while tanycyte tight junctions control their diffusion into the CSF, thus maintaining brain homeostasis. In the present work, we combined immunohistochemical and permeability studies to investigate the presence of tanycyte barriers along the ventricular walls of other brain CVOs. Our data indicate that, unlike cuboidal ependymal cells, ependymal cells bordering the CVOs possess long processes that project into the parenchyma of the CVOs to reach the fenestrated capillary network. Remarkably, these tanycyte-like cells display well-organized tight junctions around their cell bodies. Consistent with these observations, permeability studies show that this ependymal layer acts as a diffusion barrier. Together, our results suggest that tanycytes are a characteristic feature of all CVOs and yield potential new insights into their involvement in regulating the exchange between the blood, the brain, and the CSF within these "brain windows."
Collapse
Affiliation(s)
- Fanny Langlet
- Laboratory of Development and Plasticity of the Postnatal Brain, Jean-Pierre Aubert Research Centre (JPARC), Inserm U837, University of Lille 2, Lille, 59000, France
- NEUROBESE International Associated Laboratory, 59045 Lille cedex, France
- Univ Lille Nord de France, School of Medicine, 59046 Lille cedex, France
| | - Amandine Mullier
- Laboratory of Development and Plasticity of the Postnatal Brain, Jean-Pierre Aubert Research Centre (JPARC), Inserm U837, University of Lille 2, Lille, 59000, France
- NEUROBESE International Associated Laboratory, 59045 Lille cedex, France
- Univ Lille Nord de France, School of Medicine, 59046 Lille cedex, France
| | - Sebastien G. Bouret
- Laboratory of Development and Plasticity of the Postnatal Brain, Jean-Pierre Aubert Research Centre (JPARC), Inserm U837, University of Lille 2, Lille, 59000, France
- NEUROBESE International Associated Laboratory, 59045 Lille cedex, France
- Univ Lille Nord de France, School of Medicine, 59046 Lille cedex, France
- Neuroscience Program, Saban Research Institute, Childrens Hospital Los Angeles, University of Southern California, Los Angeles, CA, USA
| | - Vincent Prevot
- Laboratory of Development and Plasticity of the Postnatal Brain, Jean-Pierre Aubert Research Centre (JPARC), Inserm U837, University of Lille 2, Lille, 59000, France
- NEUROBESE International Associated Laboratory, 59045 Lille cedex, France
- Univ Lille Nord de France, School of Medicine, 59046 Lille cedex, France
| | - Benedicte Dehouck
- Laboratory of Development and Plasticity of the Postnatal Brain, Jean-Pierre Aubert Research Centre (JPARC), Inserm U837, University of Lille 2, Lille, 59000, France
- NEUROBESE International Associated Laboratory, 59045 Lille cedex, France
- Univ Lille Nord de France, School of Medicine, 59046 Lille cedex, France
- Univ Artois, Liévin, France
| |
Collapse
|
22
|
Prevot V, Langlet F, Dehouck B. Flipping the tanycyte switch: how circulating signals gain direct access to the metabolic brain. Aging (Albany NY) 2013; 5:332-4. [PMID: 23667132 PMCID: PMC3701106 DOI: 10.18632/aging.100557] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 05/09/2013] [Indexed: 11/25/2022]
|
23
|
Langlet F, Levin BE, Luquet S, Mazzone M, Messina A, Dunn-Meynell AA, Balland E, Lacombe A, Mazur D, Carmeliet P, Bouret SG, Prevot V, Dehouck B. Tanycytic VEGF-A boosts blood-hypothalamus barrier plasticity and access of metabolic signals to the arcuate nucleus in response to fasting. Cell Metab 2013; 17:607-17. [PMID: 23562080 PMCID: PMC3695242 DOI: 10.1016/j.cmet.2013.03.004] [Citation(s) in RCA: 236] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2012] [Revised: 01/12/2013] [Accepted: 03/04/2013] [Indexed: 10/27/2022]
Abstract
The delivery of blood-borne molecules conveying metabolic information to neural networks that regulate energy homeostasis is restricted by brain barriers. The fenestrated endothelium of median eminence microvessels and tight junctions between tanycytes together compose one of these. Here, we show that the decrease in blood glucose levels during fasting alters the structural organization of this blood-hypothalamus barrier, resulting in the improved access of metabolic substrates to the arcuate nucleus. These changes are mimicked by 2-deoxyglucose-induced glucoprivation and reversed by raising blood glucose levels after fasting. Furthermore, we show that VEGF-A expression in tanycytes modulates these barrier properties. The neutralization of VEGF signaling blocks fasting-induced barrier remodeling and significantly impairs the physiological response to refeeding. These results implicate glucose in the control of blood-hypothalamus exchanges through a VEGF-dependent mechanism and demonstrate a hitherto unappreciated role for tanycytes and the permeable microvessels associated with them in the adaptive metabolic response to fasting.
Collapse
Affiliation(s)
- Fanny Langlet
- Laboratory of Development and Plasticity of the Postnatal Brain, Jean-Pierre Aubert Research Centre, Inserm U837, 59000 Lille, France
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Méquinion M, Langlet F, Zgheib S, Dickson S, Dehouck B, Chauveau C, Viltart O. Ghrelin: central and peripheral implications in anorexia nervosa. Front Endocrinol (Lausanne) 2013; 4:15. [PMID: 23549309 PMCID: PMC3581855 DOI: 10.3389/fendo.2013.00015] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 02/01/2013] [Indexed: 11/15/2022] Open
Abstract
Increasing clinical and therapeutic interest in the neurobiology of eating disorders reflects their dramatic impact on health. Chronic food restriction resulting in severe weight loss is a major symptom described in restrictive anorexia nervosa (AN) patients, and they also suffer from metabolic disturbances, infertility, osteopenia, and osteoporosis. Restrictive AN, mostly observed in young women, is the third largest cause of chronic illness in teenagers of industrialized countries. From a neurobiological perspective, AN-linked behaviors can be considered an adaptation that permits the endurance of reduced energy supply, involving central and/or peripheral reprograming. The severe weight loss observed in AN patients is accompanied by significant changes in hormones involved in energy balance, feeding behavior, and bone formation, all of which can be replicated in animals models. Increasing evidence suggests that AN could be an addictive behavior disorder, potentially linking defects in the reward mechanism with suppressed food intake, heightened physical activity, and mood disorder. Surprisingly, the plasma levels of ghrelin, an orexigenic hormone that drives food-motivated behavior, are increased. This increase in plasma ghrelin levels seems paradoxical in light of the restrained eating adopted by AN patients, and may rather result from an adaptation to the disease. The aim of this review is to describe the role played by ghrelin in AN focusing on its central vs. peripheral actions. In AN patients and in rodent AN models, chronic food restriction induces profound alterations in the « ghrelin » signaling that leads to the development of inappropriate behaviors like hyperactivity or addiction to food starvation and therefore a greater depletion in energy reserves. The question of a transient insensitivity to ghrelin and/or a potential metabolic reprograming is discussed in regard of new clinical treatments currently investigated.
Collapse
Affiliation(s)
- Mathieu Méquinion
- UMR INSERM 837, Development and Plasticity of Postnatal BrainLille, France
| | - Fanny Langlet
- UMR INSERM 837, Development and Plasticity of Postnatal BrainLille, France
| | - Sara Zgheib
- Pathophysiology of inflammatory of bone diseases, Université Lille Nord de France-ULCO – Lille 2Boulogne sur Mer, France
| | - Suzanne Dickson
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of GothenburgGothenburg, Sweden
- Department of Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of GothenburgGothenburg, Sweden
| | - Bénédicte Dehouck
- UMR INSERM 837, Development and Plasticity of Postnatal BrainLille, France
- Université Lille Nord de France – Université d’ArtoisLiévin, France
| | - Christophe Chauveau
- Pathophysiology of inflammatory of bone diseases, Université Lille Nord de France-ULCO – Lille 2Boulogne sur Mer, France
| | - Odile Viltart
- UMR INSERM 837, Development and Plasticity of Postnatal BrainLille, France
- Université Lille Nord de France-USTL (Lille 1)Villeneuve d’Ascq, France
- *Correspondence: Odile Viltart, Development and Plasticity of the Postnatal Brain, Team 2, Jean-Pierre Aubert Research Center, UMR INSERM 837, Bât Biserte, 1 place de Verdun, 59,045 Lille cedex, France. e-mail:
| |
Collapse
|
25
|
Burtey S, Baume D, Mazzerbo F, Chaffanjon P, Solacroup JC, Langlet F, Zanluca S, Quilichini R. [Mechanisms of rupture of indwelling central venous catheters. 2 cases]. Presse Med 1996; 25:129. [PMID: 8746093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
|
26
|
Puddu PE, Langlet F, Lanti M, Guillen JC, Dawodu AA, Monti F, Schiariti M, Reale A. Different effects of epoprostenol on ischemia-induced ventricular arrhythmias in dogs. Cardiologia 1990; 35:551-9. [PMID: 2088600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In 60 randomized dogs the effects of epoprostenol infusion (100 ng/kg/min) on ischemia-induced premature ventricular contractions (PVCs), ventricular tachycardia (VT), ventricular flutters and ventricular fibrillation were studied. The circumflex coronary artery occlusion canine model of sudden death was used. The results demonstrate different effects of epoprostenol on ischemia-induced ventricular arrhythmias: 1) both postischemic (7 of 30 vs 15 of 30, p = 0.0298) and postreperfusion (5 of 23 vs 8 of 15, p = 0.0492) ventricular fibrillations were prevented in epoprostenol dogs with an improvement of the global survival rate (18 of 30 vs 7 of 30, p = 0.0019) as compared to controls; 2) in epoprostenol treated dogs a significantly increased incidence of non lethal arrhythmias-including ventricular flutters that occurred in 12 of 30 dogs vs 4 of 30 in controls (p = 0.0195)--was observed; 3) a positive correlation between the percent diastolic pressure fall 10 min after the start of epoprostenol infusion and the number of non lethal arrhythmias was noted. However, hemodynamic effects of the compound, suggesting an oxygen sparing action, did not preclude the antifibrillatory effectiveness. Thus, the antifibrillatory and antiarrhythmic effects of epoprostenol after circumflex coronary artery occlusion and reperfusion in dogs seem independent from one another.
Collapse
Affiliation(s)
- P E Puddu
- 2nd Department of Cardiology, University La Sapienza, School of Medicine, Rome, Italy
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Cooke RG, Warsh JJ, Stancer HC, Hasey GM, Jorna T, Langlet F. Effect of concurrent medical illness on dexamethasone suppression test results in depressed inpatients. Can J Psychiatry 1990; 35:31-5. [PMID: 2317731 DOI: 10.1177/070674379003500105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A retrospective evaluation of the clinical records of 138 depressed patients, who received the dexamethasone suppression test (DST) as part of a standardized physical and psychiatric assessment protocol, revealed that 60 had acute, chronic (mild or severe), stable or remitted medical conditions. The proportion of DST nonsuppressors did not differ between depressed subjects with medical conditions (45% nonsuppressors) and those without (34.6% nonsuppressors; p greater than 0.2). However, all of the six subjects with acute or chronic-severe medical conditions were found to be nonsuppressors (p = 0.003). These results may help clarify the medical exclusion criteria for the clinical application of the DST.
Collapse
Affiliation(s)
- R G Cooke
- Department of Psychiatry, University of Toronto, Ontario
| | | | | | | | | | | |
Collapse
|
28
|
Cooke RG, Langlet F, McLaughlin BJ. Age-specific prevalence of Epstein-Barr virus antibodies in adult patients with affective disorders. J Clin Psychiatry 1988; 49:361-3. [PMID: 2843498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
It has been suggested that prior Epstein-Barr virus (EBV) infection is a necessary condition for the development of affective disorders. To address this issue, the authors performed serologic screening for the presence of EBV antibodies in 60 adult patients seen at an affective disorders investigational unit. Six patients with clinically significant mood disorders, all aged 32 years or younger, had no detectable EBV antibodies. The authors conclude that the onset of clinical mood disorders can occur before primary EBV infection; thus, EBV infection is not a necessary condition for the development of mood disorders.
Collapse
Affiliation(s)
- R G Cooke
- Affective Disorders Unit, Clarke Institute of Psychiatry, Toronto, Ontario, Canada
| | | | | |
Collapse
|
29
|
Puddu PE, Jouve R, Langlet F, Guillen JC, Lanti M, Reale A. Prevention of postischemic ventricular fibrillation late after right or left stellate ganglionectomy in dogs. Circulation 1988; 77:935-46. [PMID: 3349588 DOI: 10.1161/01.cir.77.4.935] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
To gain insight into the differences in antiarrhythmic potential of right vs left stellate ganglionectomy, 72 dogs were randomized to either unilateral stellectomy or second intercostal space thoracotomy and left circumflex coronary arteriovenous pedicle occlusion was performed, without vagotomy, a mean of 8 weeks later under anesthesia. The type and timing of ventricular ectopic beats, including both nonsustained and sustained ventricular tachycardia and ventricular fibrillation, were investigated. Several covariates, including postischemic electrocardiographic changes, were considered. Both right and left stellate ganglionectomy reduced the incidence of early (0 to 10 min) (p = .004 and p = .001, respectively) and total (0 to 60 min) (p = .009 and p = .008, respectively) ischemia-induced ventricular fibrillation, and improved outcome (p = .0013 and p = .0012, respectively). Early sustained ventricular tachycardia was similarly reduced (p = .02) in both stellectomized groups. By contrast, neither the type nor the time distribution of the other forms of ventricular arrhythmias differed significantly among the randomized groups. The multivariate Cox's regression model showed that ST segment elevation at 3 min postocclusion, unilateral stellate ganglionectomy (either right or left), sex, and weight were significant independent predictors of the incidence of ventricular fibrillation during the occlusion period. Lower ST segment elevation and reduced incidence of sustained ventricular tachycardia in the early postischemic period might explain improved outcome in stellectomized dogs by Cox analysis. The side of intervention (either stellectomy or sham operation) did not influence survival; however, left-sided interventions were more effective than right-sided ones. These results confirm the previously reported antifibrillatory effect of left and indicate like effects of right stellate ganglionectomy in a randomized experimental study.
Collapse
Affiliation(s)
- P E Puddu
- Second Department of Cardiology, University of Rome La Sapienza School of Medicine, Italy
| | | | | | | | | | | |
Collapse
|
30
|
Puddu PE, Jouve R, Lanti M, Langlet F, Guillen JC, Serradimigni A, Reale A. [Correlation between delta R% and ST in standard electrocardiographic leads during acute myocardial ischemia in dogs]. Cardiologia 1987; 32:81-4. [PMID: 3581120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
31
|
Puddu PE, Jouve R, Langlet F, Guillen JC, Fornaris M, Torresani J, Reale A. Prevention of postischaemic ventricular fibrillation by long term beta adrenoceptor blockade with acebutolol in the anaesthetised dog. Cardiovasc Res 1986; 20:721-6. [PMID: 2431780 DOI: 10.1093/cvr/20.10.721] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Acute occlusions of the proximal left circumflex coronary arteriovenous pedicle were performed in open chest anaesthetised dogs. Twenty eight dogs were randomly allocated to receive acebutolol (3 mg X kg-1 twice daily) or placebo given blindly by mouth for five days; a control group of 14 dogs without any pretreatment underwent the same procedure. Coronary ligations in the randomised study were performed during seven consecutive days, and four dogs were operated on each day. This schedule was chosen in order to measure acebutolol plasma concentrations just before ligation from 60 to 540 min after the last dose of the drug. Long term oral treatment with acebutolol protected against postischaemic ventricular fibrillation and significantly reduced the incidence of both early phase (0-10 min postocclusion) ventricular arrhythmias and ventricular fibrillation. As a result the outcome was significantly improved after 60 min of ischaemia in acebutolol compared with placebo treated animals. The results in the control animals were similar to those in the placebo treated dogs. The protective effect of long term oral treatment with acebutolol lasted for nine hours and was apparently independent of the plasma concentrations of the drug. These data show that improved outcome in this canine model is due to the prevention of ischaemia induced ventricular fibrillation by long term beta adrenoceptor blockade, which is able to overcome the effect, if any, of partial agonist activity of acebutolol. A direct myocardial anti-ischaemic effect might explain the effectiveness of long term oral treatment, which is independent of plasma concentrations of the drug.
Collapse
|
32
|
Cano JP, Guillen JC, Jouve R, Langlet F, Puddu PE, Rolland PH, Serradimigni A. Molsidomine prevents post-ischaemic ventricular fibrillation in dogs. Br J Pharmacol 1986; 88:779-89. [PMID: 3755634 PMCID: PMC1917061 DOI: 10.1111/j.1476-5381.1986.tb16250.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Forty anaesthetized dogs were subjected to left circumflex coronary artery ligation followed by reperfusion. Molsidomine was randomly administered to 20 dogs (50 micrograms kg-1 as an i.v. bolus - 15 min prior to coronary occlusion - followed by an infusion of 0.05 micrograms kg-1 min-1. Standard electrocardiographic leads 2 and 3 were continuously recorded to measure ST segment and delta R% changes and to document both the number of ventricular premature beats and the onset of ventricular fibrillation; aortic pressure and cardiac output were measured; thromboxane B2 plasma levels, platelet aggregation produced by ADP, and molsidomine plasma levels were determined before and at 10, 30 and 75 min after the start of the drug protocol. Molsidomine protected the treated animals from early (10 min) post-ischaemic ventricular fibrillation (0 of 20 vs 6 of 20, P = 0.0202), reduced the incidence of overall post-occlusion ventricular fibrillation (3 of 20 vs 10 of 20, P = 0.0407) and improved the total survival rate (P = 0.0067). In molsidomine treated dogs: mean aortic pressure and the rate-pressure product were lowered 10 min after the start of the drug; immediate post-occlusion (3 min) ST segment changes (0.82 +/- 0.52 vs 1.52 +/- 0.78 mV, P less than 0.025) and delta R% changes (37 +/- 50 vs 90 +/- 84%, P less than 0.025) were less marked; the number of ventricular premature beats was lowered and finally, a progressive decline of platelet aggregation produced by ADP was achieved after 75 min of drug infusion. These results were obtained in the presence of mean plasma levels of molsidomine ranging from 20 to 28 ng ml-1. The time-action curve of the antifibrillatory effect of molsidomine parallels those at the level of post-ischaemic electrocardiographic changes.
Collapse
|
33
|
Goudard A, Blin D, Langlet F, Mesana T, N'Guimbous JF. [Use of elastic laces with attached needle in coronary surgery]. Presse Med 1986; 15:1153-4. [PMID: 2942912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Using elastic laces with attached needle for surgery of the coronary arteries ensures adequate exposure, presentation and drying up of these vessels during distal anastomosis.
Collapse
|
34
|
Jouve R, Puddu PE, Langlet F, Guillen JC, Serradimigni A. The circumflex coronary artery occlusion canine model of sudden death: methodology and electrocardiographic observations. J Electrocardiol 1986; 19:155-64. [PMID: 3711753 DOI: 10.1016/s0022-0736(86)80023-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
This study deals with a left circumflex coronary artery occlusion-reperfusion canine model of sudden death using multiple electrocardiographic leads to define a subgroup of animals at high risk of ventricular fibrillation. Occlusion was followed by ventricular fibrillation in 15 of 30 animals (50%). In the 15 dogs surviving 60 min postocclusion, reperfusion gave rise to ten cases of ventricular fibrillation (66.7%). Thus, the total incidence of occlusion-reperfusion ventricular fibrillation was 25 of 30 (83.3%). Electrocardiographic delta R% changes greater than or equal to 25% in leads 2 and 3 at both 3 and 5 min postocclusion predicted the occurrence of postocclusion ventricular fibrillation with 80% specificity and 56% sensitivity. However, ST segment elevation greater than or equal to 0.5 mV in the same leads at the same times predicted postocclusion ventricular fibrillation with 67% specificity and 100% sensitivity. When only dogs with ST segment elevation greater than or equal to 0.5 mV in leads 2 and 3 at both 3 and 5 min postocclusion were considered, ventricular fibrillation postocclusion was seen in 15 of 20 dogs (75%) and ventricular fibrillation after reperfusion occurred in four of the remaining five animals (80%). Thus, in the subgroup of animals presenting with ST segment elevation greater than or equal to 0.5 mV in leads 2 and 3 at both 3 and 5 min postocclusion, the overall incidence of occlusion-reperfusion ventricular fibrillation was 19 of 20 (95%). These data may be useful in studies aimed at testing the effectiveness of drugs or other interventions in a canine model of sudden death.
Collapse
|
35
|
Jouve R, Langlet F, Puddu PE, Rolland PH, Guillen JC, Cano JP, Serradimigni A. Cicletanide improves outcome after left circumflex coronary artery occlusion-reperfusion in the dog. J Cardiovasc Pharmacol 1986; 8:208-15. [PMID: 2419686 DOI: 10.1097/00005344-198601000-00030] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The possible antifibrillatory effect of cicletanide, a new diuretic antihypertensive drug, was investigated at random in 50 anesthetized dogs subjected to left circumflex coronary artery ligation for 60 min and later reperfused. In this model, standard electrocardiographic leads 2 and 3 were continuously registered to measure delta R wave percent changes, to count the number of ventricular premature beats, and to document the onset of ventricular fibrillation; aortic pressure was recorded; 6-keto PGF1 alpha and TXB2 plasma levels were determined. Cicletanide significantly reduced early (Phase 1a) postischemic ventricular fibrillation (5 of 25 vs. 12 of 25, p = 0.036) but failed to reduce the incidence of global ischemia-induced ventricular fibrillation. On the other hand, the incidence of postreperfusion ventricular fibrillation was lower in the cicletanide group (1 of 14 vs. 5 of 9, p = 0.04). In addition, the total survival rate was improved in cicletanide treated dogs (p = 0.0257). While the rate-pressure product was lowered by the drug independent of the presence of ischemia, delta R% changes after occlusion were less in treated dogs than in controls. Moreover, the drug reduced significantly the number of ventricular premature beats in the early (Phase 1a) postischemic period. Finally, the drug increased (mean two-fold) the plasma levels of 6-keto PGF1 alpha as compared with controls; however, this increase was less than that achieved (mean 20-fold) after 100 ng/kg/min epoprostenol (prostacyclin) given in a further series of animals. Thus, improved outcome follows 10 mg/kg i.v. cicletanide administration in this model.
Collapse
|
36
|
Jouve R, Puddu PE, Langlet F, Guillen JC, Gautier T, Cano JP, Serradimigni A. Epoprostenol (PGI2) prevents postischemic ventricular fibrillation and improves outcome in a canine model of sudden death. J Pharmacol 1985; 16:139-57. [PMID: 3903352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In a left circumflex coronary artery occlusion-reperfusion canine model of sudden death the hemodynamic, antiplatelet, antiischemic and antifibrillatory activities of 100 ng.kg-1.min-1 infusion of epoprostenol (Prostacyclin, Flolan, Wellcome Foundation, London, UK) were investigated at random in 40 animals. Significant changes were observed on epoprostenol infusion for mean arterial blood pressure (80 +/- 4 vs 93 +/- 7 mmHg, p less than 0.01), systemic vascular resistance (2379 +/- 769 vs 3290 +/- 768 dynes.s.cm-5, p less than 0.01) and rate-pressure product (10800 +/- 1200 vs 13450 +/- 2500 mmHg.beat.min-1, p less than 0.01) while heart rate did not change. In addition platelet aggregation intensity to ADP decreased by 50% (p less than 0.001). On occlusion treated animals presented with lower systemic vascular resistance (3132 +/- 895 vs 4931 +/- 1079 dynes.s.cm-5, p less than 0.05), rate-pressure product (9950 +/- 850 vs 12168 +/- 1980 mmHg.beat.min-1, p less than 0.01) and mean heart rate (145 +/- 10 vs 169 +/- 10 beats.min-1, p less than 0.01) while the anti-platelet activity persisted. A lower D2-3 mean ST segment elevation occurred at 3 min postocclusion in epoprostenol treated dogs (7.7 +/- 5 vs 14 +/- 8.7 mm, p less than 0.02). The incidence of postischemic ventricular fibrillation was significantly reduced (5/20 i.e. 25% vs 12/20 i.e. 60%, p less than 0.05) in the epoprostenol treated dogs. At the end of the occlusion-reperfusion period treated animals showed an improvement of outcome (10/20 i.e. 50% vs 2/20 i.e. 10%, p less than 0.01). It is suggested that the hemodynamic effect of the drug may provide guidelines for the clinical management of patients with acute myocardial ischemia, when a concomitant antiarrhythmic effect is looked for.
Collapse
|
37
|
Jouve R, Puddu PE, Langlet F, Guillen JC, Serradimigni A. Epoprostenol (PGI2) reduces the incidence of post-reperfusion ventricular fibrillation in the dog. Cardiologia 1985; 30:91-7. [PMID: 3905005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
38
|
Matina D, Mouly A, Massol J, Gatau-Pélanchon J, Blin D, Langlet F, Lévy S, Montiès JR, Gérard R. [Ventricular arrhythmia following repair of Fallot's tetralogy. Apropos of 59 cases]. Arch Mal Coeur Vaiss 1985; 78:103-10. [PMID: 3919669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Fifty-nine patients operated for Fallot's tetralogy were reviewed over 3 years after surgery. The average age at surgery was 7.4 years (range 6 months to 37 years). The review included ECG, chest X-ray, echocardiography, exercise stress testing and Holter monitoring, completed by cardiac catheterisation in 10 cases and electrophysiological investigation in 4 cases. Forty-eight of the 59 patients (81.3 p. 100) had no signs of ventricular arrhythmia or only benign ventricular extrasystoles (Group I). Four patients (6.8 p. 100) had severe ventricular arrhythmias (Group II). Seven patients (11.9 p. 100) had one or more episodes of ventricular tachycardia (VT) (Group III) and, in 3 of these patients, VT was recorded during Holter monitoring or exercise stress testing. One patient in Group III died after reoperation, but there were no cases of sudden death in this series. The high risk patients Groups II and III) were operated late (after 5 years), had bi- or trifascicular block (7 out of 11 cases), ventricular extrasystoles on resting ECGs (9 out of 11 cases), cardiomegaly (6 out of 7 cases in Group III), echocardiographic dilatation of the infundibulum (6 out of the 8 patients undergoing echocardiography in Groups II and III). They had significant residual malformation but without right ventricular hypertension (as judged mainly by immediate postoperative data). Ventricular arrhythmias occurred over 6 years after surgery. However, none of the patients operated before 2 years of age had ventricular arrhythmias or VT with a mean follow-up period of 7.5 years, perhaps because LV function was protected.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|
39
|
Mostefa Kara M, Langlet F, Blin D, Mouly-Bandini A, Goudard A, Monties JR. [Bioprosthesis in children and adolescents]. Ann Chir 1984; 38:499-504. [PMID: 6508179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
40
|
Goudard A, Avierinos C, Mouly A, Blin D, Langlet F, Kara MM, Monties JR. [Selective tricuspid annuloplasty without prosthetic support]. Presse Med 1984; 13:737-8. [PMID: 6231580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Two techniques of plastic surgery are currently used to treat tricuspid insufficiency: a prosthetic reductor or a continuous running suture. In the technique advocated here a double continuous suture is inserted into the tricuspid annulus, one running from the antero-septal to the antero-external commissures and the other, from the postero-septal to the antero-external commissures. When these two sutures are tied separately, the circumferences of the two parts of the annulus, which are diversely dilated, can be reduced. The authors have used this technique in 141 patients and a Carpentier's annulus in 41 patients. Perioperative mortality and 5-year survival were the same in both series, but the incidence of postoperative atrioventricular block was much lower in the first one. Another advantage of the double continuous suture technique is that foreign material is reduced to a minimum.
Collapse
|
41
|
Mostefa-Kara M, Blin D, Langlet F, Mouly A, Goudard A, Montiès JR. [Mitral valve replacement with bioprosthesis in children]. Arch Mal Coeur Vaiss 1984; 77:161-166. [PMID: 6424600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Forty seven bioprostheses were used for mitral valve replacement between January 1975 and June 1980, with no operative mortality, in children under 19 years of age. This study was undertaken to evaluate the medium and longterm outcome of 43 patients followed up for at least 2 years. The late mortality was higher in children under 13 years of age (11.1% per patient/year) than in older children (3% per patient/year). The incidence of reoperation for deterioration of the bioprosthesis was 5,5% per patient/year. The actuarial longevity of bioprostheses without any complications was 48 +/- 16% at 5 years. After a review of the literature, the authors discuss their present therapeutic attitude: whenever possible, mitral valvuloplasty is the operation of choice, but when valve replacement is necessary, two criteria must be considered: the age of the patient and conditions of follow up. If medical follow-up facilities are good: mechanical prostheses are preferred in patients under 13 years of age: after puberty especially in girls, the bioprosthesis is the valve of choice. If medical follow-up facilities are poor: the valve of choice is a bioprosthesis at all ages because of the risk of thromboembolism and the relatively slow clinical aggravation in cases of bioprosthetic deterioration.
Collapse
|
42
|
Jacqueme P, Xeridat B, Badier M, Bru P, Langlet F, Sainty JM. [Suppurative Haemophilus influenzae pericarditis in adults]. Presse Med 1984; 13:167-8. [PMID: 6229751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
|
43
|
Abstract
A new presentation of ECG tracings is presented (contourography) which is suitable for ECG intervals measurements, particularly QT for prolonged periods of time. Possible applications of this method are looked for in the future.
Collapse
|
44
|
Henry JF, Saingra S, Langlet F, France G, Grisoli J. [Parathyroid autotransplantation in hemodialysed chronic renal failure. Attempts to modulate secretion. First results apropos of 45 cases]. Sem Hop 1983; 59:23-8. [PMID: 6297082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The authors report their experience of parathyroid autotransplantation in 45 cases of renal insufficiency undergoing hemodialysis. The operation, carried out by two teams, reduces to the minimum the time during which the grafts are exposed to environmental factors likely to impair their function. An immediate anatomopathological examination is necessary to determine the degree of hyperplasia in each gland and the corresponding choice of grafts. The tissue to be implanted must be raised in the least hyperplastic gland and the size of the graft, always difficult to specify, is dictated by the intensity of the hyperplasia. This technique ultimately permits and almost permanent modulation of the parathyroid secretion by action on the secreting tissue. In the event of post-operative persistent hypoparathyroidism, a second operation is desirable, using cryopreserved fragments for the implant. Conversely, in the event of clinical and biological recurrence, the ablation of a precise volume of grafted tissue can be performed without difficulty, under local anaesthetic.
Collapse
|
45
|
Henry JF, Saingra S, Langlet F, France G, Grisoli J. [Parathyroid autotransplantation in patients undergoing hemodialysis for renal insufficiency. Attempts to modulate secretion. First results of forty-five cases ]. Ann Chir 1982; 36:257-62. [PMID: 7125528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
46
|
Abstract
Forty-two male patients with ano-genital warts were randomly allocated to a single-blind study of cryotherapy versus electrocautery. There was no significant difference in the success rates of these two forms of treatment in patients followed for three months. Cryotherapy was qualitatively much more acceptable to the patients than electrocautery. It seems particularly suited to patients with widely scattered warts who are unable to attend for regular treatment.
Collapse
|
47
|
Simmons PD, Forsey T, Thin RN, Treharne JD, Darougar S, Langlet F, Pandhi RK. Antichlamydial antibodies in pelvic inflammatory disease. Br J Vener Dis 1979; 55:419-21. [PMID: 526845 PMCID: PMC1045701 DOI: 10.1136/sti.55.6.419] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The role of Chlamydia trachomatis in pelvic inflammatory disease (PID) diagnosed without laparoscopy was assessed by measuring antichlamydial antibodies in the patient's serum and by comparing the results with those in patients with uncomplicated non-specific genital infection (NSGI) and gonorrhoea and in non-infected controls. A modified microimmunofluorescence test was used. Patients with severe PID had significantly more positive antichlamydial IgG and IgM results than did control subjects, patients with gonorrhoea, and patients with NSGI. Less severe PID was associated with significantly raised levels of antichlamydial IgG antibodies compared with NSGI and controls and with raised levels of IgM antibodies compared with controls. Two patients with PID had lower genital tract gonorrhoea, one of whom had raised antichlamydial antibody levels. These findings may indicate a mixed infection and therapy should be reviewed in such patients. A serological diagnosis of chlamydial infection is relatively easy and cheap and enables a rapid diagnosis of chlamydial infection to be made.
Collapse
|
48
|
Thin RN, Symonds MA, Booker R, Cook S, Langlet F. Double-blind comparison of a single dose and a five-day course of metronidazole in the treatment of trichomoniasis. Br J Vener Dis 1979; 55:354-6. [PMID: 389352 PMCID: PMC1045680 DOI: 10.1136/sti.55.5.354] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Although there have been reports of the results of treating trichomoniasis with metronidazole 2 g in a single dose, no randomised double-blind comparison of this treatment with a multiple-dose regimen has been reported. In such a comparison, 96 women were treated with metronidazole 2 g in a single dose and 96 women with metronidazole 400 mg twice daily for five days. Forty-eight of 52 women followed for 14 days after the single dose were cured, as were 61 of 66 women followed for 14 days after the start of the five-day regimen. These results compare favourably with previous reports. Side effects were trivial, and we recommend the single 2-g dose, for it is effective, economical, and can be given under supervision in the clinic.
Collapse
|
49
|
Giudicelli R, Arion H, Rubidovsky J, Langlet F, Noirclerc M. [Filling the pleural cavities after pulmonary exeresis. Experimental results using a silicone prosthesis (author's transl)]. Ann Chir 1979; 33:151-4. [PMID: 507686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|