1
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Zhou S, Makashova O, Chevillard PM, Josey V, Li B, Prager-Khoutorsky M. Constitutive cell proliferation and neurogenesis in the organum vasculosum lamina terminalis and subfornical organ of adult rats. J Neuroendocrinol 2024; 36:e13377. [PMID: 38418229 DOI: 10.1111/jne.13377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 02/08/2024] [Accepted: 02/09/2024] [Indexed: 03/01/2024]
Abstract
Neurogenesis continues throughout adulthood in the subventricular zone, hippocampal subgranular zone, and the hypothalamic median eminence (ME) and the adjacent medio-basal hypothalamus. The ME is one of the circumventricular organs (CVO), which are specialized brain areas characterized by an incomplete blood-brain barrier and, thus, are involved in mediating communication between the central nervous system and the periphery. Additional CVOs include the organum vasculosum laminae terminalis (OVLT) and the subfornical organs (SFO). Previous studies have demonstrated that the ME contains neural stem cells (NSCs) capable of generating new neurons and glia in the adult brain. However, it remains unclear whether the OVLT and SFO also contain proliferating cells, the identity of these cells, and their ability to differentiate into mature neurons. Here we show that glial and mural subtypes exhibit NSC characteristics, expressing the endogenous mitotic maker Ki67, and incorporating the exogenous mitotic marker BrdU in the OVLT and SFO of adult rats. Glial cells constitutively proliferating in the SFO comprise NG2 glia, while in the OVLT, both NG2 glia and tanycytes appear to constitute the NSC pool. Furthermore, pericytes, which are mural cells associated with capillaries, also contribute to the pool of cells constitutively proliferating in the OVLT and SFO of adult rats. In addition to these glial and mural cells, a fraction of NSCs containing proliferation markers Ki67 and BrdU also expresses the early postmitotic neuronal marker doublecortin, suggesting that these CVOs comprise newborn neurons. Notably, these neurons can differentiate and express the mature neuronal marker NeuN. These findings establish the sensory CVOs OVLT and SFO as additional neurogenic niches, where the generation of new neurons and glia persists in the adult brain.
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Affiliation(s)
- Suijian Zhou
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Québec, Canada
| | - Olena Makashova
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Québec, Canada
| | - Pierre-Marie Chevillard
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Québec, Canada
| | - Vanessa Josey
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Québec, Canada
| | - Banruo Li
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Québec, Canada
| | - Masha Prager-Khoutorsky
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Québec, Canada
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2
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Stocker SD, Kinsman BJ, Farquhar WB, Gyarmati G, Peti-Peterdi J, Sved AF. Physiological Mechanisms of Dietary Salt Sensing in the Brain, Kidney, and Gastrointestinal Tract. Hypertension 2024; 81:447-455. [PMID: 37671571 PMCID: PMC10915107 DOI: 10.1161/hypertensionaha.123.19488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Excess dietary salt (NaCl) intake is strongly correlated with cardiovascular disease and is a major contributing factor to the pathogenesis of hypertension. NaCl-sensitive hypertension is a multisystem disorder that involves renal dysfunction, vascular abnormalities, and neurogenically-mediated increases in peripheral resistance. Despite a major research focus on organ systems and these effector mechanisms causing NaCl-induced increases in arterial blood pressure, relatively less research has been directed at elucidating how NaCl is sensed by various tissues to elicit these downstream effects. The purpose of this review is to discuss how the brain, kidney, and gastrointestinal tract sense NaCl including key cell types, the role of NaCl versus osmolality, and the underlying molecular and electrochemical mechanisms.
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Affiliation(s)
- Sean D. Stocker
- Department of Neurobiology, University of Pittsburgh School of Medicine
| | - Brian J Kinsman
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital
| | | | - Georgina Gyarmati
- Department of Physiology and Neuroscience and Medicine, Zilkha Neurogenetic Institute, University of Southern California
| | - Janos Peti-Peterdi
- Department of Physiology and Neuroscience and Medicine, Zilkha Neurogenetic Institute, University of Southern California
| | - Alan F. Sved
- Department of Neuroscience, University of Pittsburgh
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3
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Hiyama TY. Brain sodium sensing for regulation of thirst, salt appetite, and blood pressure. Physiol Rep 2024; 12:e15970. [PMID: 38479999 PMCID: PMC10937250 DOI: 10.14814/phy2.15970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 02/29/2024] [Indexed: 03/17/2024] Open
Abstract
The brain possesses intricate mechanisms for monitoring sodium (Na) levels in body fluids. During prolonged dehydration, the brain detects variations in body fluids and produces sensations of thirst and aversions to salty tastes. At the core of these processes Nax , the brain's Na sensor, exists. Specialized neural nuclei, namely the subfornical organ (SFO) and organum vasculosum of the lamina terminalis (OVLT), which lack the blood-brain barrier, play pivotal roles. Within the glia enveloping the neurons in these regions, Nax collaborates with Na+ /K+ -ATPase and glycolytic enzymes to drive glycolysis in response to elevated Na levels. Lactate released from these glia cells activates nearby inhibitory neurons. The SFO hosts distinct types of angiotensin II-sensitive neurons encoding thirst and salt appetite, respectively. During dehydration, Nax -activated inhibitory neurons suppress salt-appetite neuron's activity, whereas salt deficiency reduces thirst neuron's activity through cholecystokinin. Prolonged dehydration increases the Na sensitivity of Nax via increased endothelin expression in the SFO. So far, patients with essential hypernatremia have been reported to lose thirst and antidiuretic hormone release due to Nax -targeting autoantibodies. Inflammation in the SFO underlies the symptoms. Furthermore, Nax activation in the OVLT, driven by Na retention, stimulates the sympathetic nervous system via acid-sensing ion channels, contributing to a blood pressure elevation.
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Affiliation(s)
- Takeshi Y. Hiyama
- Department of Integrative PhysiologyTottori University Graduate School and Faculty of MedicineYonagoJapan
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4
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Matsuda T, Kobayashi K, Kobayashi K, Noda M. Two parabrachial Cck neurons involved in the feedback control of thirst or salt appetite. Cell Rep 2024; 43:113619. [PMID: 38157299 DOI: 10.1016/j.celrep.2023.113619] [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: 02/23/2023] [Revised: 11/20/2023] [Accepted: 12/08/2023] [Indexed: 01/03/2024] Open
Abstract
Thirst and salt appetite are temporarily suppressed after water and salt ingestion, respectively, before absorption; however, the underlying neural mechanisms remain unclear. The parabrachial nucleus (PBN) is the relay center of ingestion signals from the digestive organs. We herein identify two distinct neuronal populations expressing cholecystokinin (Cck) mRNA in the lateral PBN that are activated in response to water and salt intake, respectively. The two Cck neurons in the dorsal-lateral compartment of the PBN project to the median preoptic nucleus and ventral part of the bed nucleus of the stria terminalis, respectively. The optogenetic stimulation of respective Cck neurons suppresses thirst or salt appetite under water- or salt-depleted conditions. The combination of optogenetics and in vivo Ca2+ imaging during ingestion reveals that both Cck neurons control GABAergic neurons in their target nuclei. These findings provide the feedback mechanisms for the suppression of thirst and salt appetite after ingestion.
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Affiliation(s)
- Takashi Matsuda
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Fukushima 960-1295, Japan
| | - Masaharu Noda
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan.
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5
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Zhang Y, Pool AH, Wang T, Liu L, Kang E, Zhang B, Ding L, Frieda K, Palmiter R, Oka Y. Parallel neural pathways control sodium consumption and taste valence. Cell 2023; 186:5751-5765.e16. [PMID: 37989313 PMCID: PMC10761003 DOI: 10.1016/j.cell.2023.10.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 09/04/2023] [Accepted: 10/19/2023] [Indexed: 11/23/2023]
Abstract
The hedonic value of salt fundamentally changes depending on the internal state. High concentrations of salt induce innate aversion under sated states, whereas such aversive stimuli transform into appetitive ones under sodium depletion. Neural mechanisms underlying this state-dependent salt valence switch are poorly understood. Using transcriptomics state-to-cell-type mapping and neural manipulations, we show that positive and negative valences of salt are controlled by anatomically distinct neural circuits in the mammalian brain. The hindbrain interoceptive circuit regulates sodium-specific appetitive drive , whereas behavioral tolerance of aversive salts is encoded by a dedicated class of neurons in the forebrain lamina terminalis (LT) expressing prostaglandin E2 (PGE2) receptor, Ptger3. We show that these LT neurons regulate salt tolerance by selectively modulating aversive taste sensitivity, partly through a PGE2-Ptger3 axis. These results reveal the bimodal regulation of appetitive and tolerance signals toward salt, which together dictate the amount of sodium consumption under different internal states.
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Affiliation(s)
- Yameng Zhang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Allan-Hermann Pool
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA; Departments of Neuroscience and Anesthesia and Pain Management and Peter O'Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Tongtong Wang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Lu Liu
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Elin Kang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Bei Zhang
- Spatial Genomics, Inc., Pasadena, CA, USA
| | - Liang Ding
- Spatial Genomics, Inc., Pasadena, CA, USA
| | | | - Richard Palmiter
- Departments of Biochemistry and Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Yuki Oka
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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Salgado-Mozo S, Thirouin ZS, Wyrosdic JC, García-Hernández U, Bourque CW. Na X Channel Is a Physiological [Na +] Detector in Oxytocin- and Vasopressin-Releasing Magnocellular Neurosecretory Cells of the Rat Supraoptic Nucleus. J Neurosci 2023; 43:8306-8316. [PMID: 37783507 PMCID: PMC10711705 DOI: 10.1523/jneurosci.1203-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 09/08/2023] [Accepted: 09/25/2023] [Indexed: 10/04/2023] Open
Abstract
The Scn7A gene encodes NaX, an atypical noninactivating Na+ channel, whose expression in sensory circumventricular organs is essential to maintain homeostatic responses for body fluid balance. However, NaX has also been detected in homeostatic effector neurons, such as vasopressin (VP)-releasing magnocellular neurosecretory cells (MNCVP) that secrete VP (antidiuretic hormone) into the bloodstream in response to hypertonicity and hypernatremia. Yet, the physiological relevance of NaX expression in these effector cells remains unclear. Here, we show that rat MNCVP in males and females is depolarized and excited in proportion with isosmotic increases in [Na+]. These responses were caused by an inward current resulting from a cell-autonomous increase in Na+ conductance. The Na+-evoked current was unaffected by blockers of other Na+-permeable ion channels but was significantly reduced by shRNA-mediated knockdown of Scn7A expression. Furthermore, reducing the density of NaX channels selectively impaired the activation of MNCVP by systemic hypernatremia without affecting their responsiveness to hypertonicity in vivo These results identify NaX as a physiological Na+ sensor, whose expression in MNCVP contributes to the generation of homeostatic responses to hypernatremia.SIGNIFICANCE STATEMENT In this study, we provide the first direct evidence showing that the sodium-sensing channel encoded by the Scn7A gene (NaX) mediates cell-autonomous sodium detection by MNCs in the low millimolar range and that selectively reducing the expression of these channels in MNCs impairs their activation in response to a physiologically relevant sodium stimulus in vitro and in vivo These data reveal that NaX operates as a sodium sensor in these cells and that the endogenous sensory properties of osmoregulatory effector neurons contribute to their homeostatic activation in vivo.
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Affiliation(s)
- Sandra Salgado-Mozo
- Brain Repair and Integrative Neuroscience Program, Research Institute of McGill University Health Center, Montréal, Québec H3G1A4, Canada
- Department of Physiology, Biophysics and Neurosciences, Centre for Research and Advanced Studies, Instituto Politecnico Nacional, 07360 Mexico City, Mexico
| | - Zahra S Thirouin
- Brain Repair and Integrative Neuroscience Program, Research Institute of McGill University Health Center, Montréal, Québec H3G1A4, Canada
| | - Joshua C Wyrosdic
- Brain Repair and Integrative Neuroscience Program, Research Institute of McGill University Health Center, Montréal, Québec H3G1A4, Canada
| | - Ubaldo García-Hernández
- Department of Physiology, Biophysics and Neurosciences, Centre for Research and Advanced Studies, Instituto Politecnico Nacional, 07360 Mexico City, Mexico
| | - Charles W Bourque
- Brain Repair and Integrative Neuroscience Program, Research Institute of McGill University Health Center, Montréal, Québec H3G1A4, Canada
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Wang J, Lv F, Yin W, Gao Z, Liu H, Wang Z, Sun J. The organum vasculosum of the lamina terminalis and subfornical organ: regulation of thirst. Front Neurosci 2023; 17:1223836. [PMID: 37732311 PMCID: PMC10507174 DOI: 10.3389/fnins.2023.1223836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 08/22/2023] [Indexed: 09/22/2023] Open
Abstract
Thirst and water intake are regulated by the organum vasculosum of the lamina terminalis (OVLT) and subfornical organ (SFO), located around the anteroventral third ventricle, which plays a critical role in sensing dynamic changes in sodium and water balance in body fluids. Meanwhile, neural circuits involved in thirst regulation and intracellular mechanisms underlying the osmosensitive function of OVLT and SFO are reviewed. Having specific Nax channels in the glial cells and other channels (such as TRPV1 and TRPV4), the OVLT and SFO detect the increased Na+ concentration or hyperosmolality to orchestrate osmotic stimuli to the insular and cingulate cortex to evoke thirst. Meanwhile, the osmotic stimuli are relayed to the supraoptic nucleus (SON) and paraventricular nucleus of the hypothalamus (PVN) via direct neural projections or the median preoptic nucleus (MnPO) to promote the secretion of vasopressin which plays a vital role in the regulation of body fluid homeostasis. Importantly, the vital role of OVLT in sleep-arousal regulation is discussed, where vasopressin is proposed as the mediator in the regulation when OVLT senses osmotic stimuli.
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Affiliation(s)
- Jiaxu Wang
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Fenglin Lv
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Wei Yin
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Zhanpeng Gao
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Hongyu Liu
- Institute of Sport and Exercise Medicine, North University of China, Taiyuan, China
| | - Zhen Wang
- Department of Cardiology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Jinhao Sun
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
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8
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Duriez A, Bergerot C, Cone JJ, Roitman MF, Gutkin B. Homeostatic Reinforcement Theory Accounts for Sodium Appetitive State- and Taste-Dependent Dopamine Responding. Nutrients 2023; 15:nu15041015. [PMID: 36839372 PMCID: PMC9968091 DOI: 10.3390/nu15041015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 02/09/2023] [Accepted: 02/11/2023] [Indexed: 02/22/2023] Open
Abstract
Seeking and consuming nutrients is essential to survival and the maintenance of life. Dynamic and volatile environments require that animals learn complex behavioral strategies to obtain the necessary nutritive substances. While this has been classically viewed in terms of homeostatic regulation, recent theoretical work proposed that such strategies result from reinforcement learning processes. This theory proposed that phasic dopamine (DA) signals play a key role in signaling potentially need-fulfilling outcomes. To examine links between homeostatic and reinforcement learning processes, we focus on sodium appetite as sodium depletion triggers state- and taste-dependent changes in behavior and DA signaling evoked by sodium-related stimuli. We find that both the behavior and the dynamics of DA signaling underlying sodium appetite can be accounted for by a homeostatically regulated reinforcement learning framework (HRRL). We first optimized HRRL-based agents to sodium-seeking behavior measured in rodents. Agents successfully reproduced the state and the taste dependence of behavioral responding for sodium as well as for lithium and potassium salts. We then showed that these same agents account for the regulation of DA signals evoked by sodium tastants in a taste- and state-dependent manner. Our models quantitatively describe how DA signals evoked by sodium decrease with satiety and increase with deprivation. Lastly, our HRRL agents assigned equal preference for sodium versus the lithium containing salts, accounting for similar behavioral and neurophysiological observations in rodents. We propose that animals use orosensory signals as predictors of the internal impact of the consumed good and our results pose clear targets for future experiments. In sum, this work suggests that appetite-driven behavior may be driven by reinforcement learning mechanisms that are dynamically tuned by homeostatic need.
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Affiliation(s)
- Alexia Duriez
- Group for Neural Theory, LNC2 DEC ENS, PSL University, 75005 Paris, France
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Clémence Bergerot
- Group for Neural Theory, LNC2 DEC ENS, PSL University, 75005 Paris, France
- Charité—Universitätsmedizin Berlin, Einstein Center for Neurosciences Berlin, 10117 Berlin, Germany
- Institute for Theoretical Biology, Department of Biology, Humboldt-Universität zu Berlin, Philippstraße 13, 10115 Berlin, Germany
- Bernstein Center for Computational Neuroscience Berlin, Philippstr. 13, 10115 Berlin, Germany
| | - Jackson J. Cone
- Hotchkiss Brain Institute, Department of Psychology, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Mitchell F. Roitman
- Department of Psychology, University of Illinois Chicago, Chicago, IL 60607, USA
| | - Boris Gutkin
- Group for Neural Theory, LNC2 DEC ENS, PSL University, 75005 Paris, France
- Correspondence: ; Tel.: +33-(0)6-8631-6231
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9
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Miyata S. Glial functions in the blood-brain communication at the circumventricular organs. Front Neurosci 2022; 16:991779. [PMID: 36278020 PMCID: PMC9583022 DOI: 10.3389/fnins.2022.991779] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
The circumventricular organs (CVOs) are located around the brain ventricles, lack a blood-brain barrier (BBB) and sense blood-derived molecules. This review discusses recent advances in the importance of CVO functions, especially glial cells transferring periphery inflammation signals to the brain. The CVOs show size-limited vascular permeability, allowing the passage of molecules with molecular weight <10,000. This indicates that the lack of an endothelial cell barrier does not mean the free movement of blood-derived molecules into the CVO parenchyma. Astrocytes and tanycytes constitute a dense barrier at the distal CVO subdivision, preventing the free diffusion of blood-derived molecules into neighboring brain regions. Tanycytes in the CVOs mediate communication between cerebrospinal fluid and brain parenchyma via transcytosis. Microglia and macrophages of the CVOs are essential for transmitting peripheral information to other brain regions via toll-like receptor 2 (TLR2). Inhibition of TLR2 signaling or depletion of microglia and macrophages in the brain eliminates TLR2-dependent inflammatory responses. In contrast to TLR2, astrocytes and tanycytes in the CVOs of the brain are crucial for initiating lipopolysaccharide (LPS)-induced inflammatory responses via TLR4. Depletion of microglia and macrophages augments LPS-induced fever and chronic sickness responses. Microglia and macrophages in the CVOs are continuously activated, even under normal physiological conditions, as they exhibit activated morphology and express the M1/M2 marker proteins. Moreover, the microglial proliferation occurs in various regions, such as the hypothalamus, medulla oblongata, and telencephalon, with a marked increase in the CVOs, due to low-dose LPS administration, and after high-dose LPS administration, proliferation is seen in most brain regions, except for the cerebral cortex and hippocampus. A transient increase in the microglial population is beneficial during LPS-induced inflammation for attenuating sickness response. Transient receptor potential receptor vanilloid 1 expressed in astrocytes and tanycytes of the CVOs is responsible for thermoregulation upon exposure to a warm environment less than 37°C. Alternatively, Nax expressed in astrocytes and tanycytes of the CVOs is crucial for maintaining body fluid homeostasis. Thus, recent findings indicate that glial cells in the brain CVOs are essential for initiating neuroinflammatory responses and maintaining body fluid and thermal homeostasis.
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10
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Fernandes-Costa F, de Lima Flôr AF, de Andrade Braga V, Campos Cruz J. Lactate inhibited sodium intake in dehydrated rats. Appetite 2022; 175:106046. [PMID: 35461891 DOI: 10.1016/j.appet.2022.106046] [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: 11/30/2021] [Revised: 04/03/2022] [Accepted: 04/09/2022] [Indexed: 11/19/2022]
Abstract
Recent studies have suggested that glial cells, especially astrocytes, are involved in balanced hydromineral modulation. In response to increased extracellular Na+ concentration, astrocytic Nax channels are activated, promoting lactate production and release. Furthermore, previous in vitro studies have suggested that lactate and hypertonic Na + solution activate SFO GABAergic neurons involved in the salt-appetite central pathways. Here, we evaluated the role of lactate in dehydration-induced sodium and water intake. To this end, intracerebroventricular microinjection (icv) of l-lactate or α-cyano-4-hydroxycinnamic acid (α-CHCA, MCT lactate transporter inhibitor) was performed in rats subjected to 48 h of water deprivation (WD) and 1 h of partial rehydration after 48 h of WD (WD-PR). The rehydration protocol was used to distinguish the mechanisms of thirst and sodium appetite induced by WD. Then, water and sodium (0.3 M NaCl) intake were evaluated for 2 h. Our results showed that central α-CHCA induced an increase in sodium preference in WD rats. Furthermore, central lactate increased water intake but reduced sodium intake in WD-PR animals. In contrast, central lactate transporter inhibition did not change water or sodium intake in WD-PR rats. Our results suggest that lactate is involved in inhibitory mechanisms that induce sodium intake avoidance in dehydrated rats.
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Affiliation(s)
| | | | - Valdir de Andrade Braga
- Departamento de Biotecnologia, Centro de Biotecnologia, Universidade Federal da Paraíba, Brazil
| | - Josiane Campos Cruz
- Departamento de Biotecnologia, Centro de Biotecnologia, Universidade Federal da Paraíba, Brazil.
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11
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Fernandes-Costa F, de Lima Flôr AF, Falcão MSF, de Moura Balarini C, de Brito Alves JL, de Andrade Braga V, de Campos Cruz J. Central interaction between nitric oxide, lactate and glial cells to modulate water and sodium intake in rats. Brain Res Bull 2022; 186:1-7. [PMID: 35487385 DOI: 10.1016/j.brainresbull.2022.04.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 04/07/2022] [Accepted: 04/23/2022] [Indexed: 12/23/2022]
Abstract
The "astrocyte-to-neuron lactate shuttle" (ANLS) mechanism is part of the central inhibitory pathway to modulate sodium intake. An interaction between the GABAergic neurons and nitric oxide (NO) in the subfornical organ (SFO) in salt-appetite inhibition has been suggested. In addition, NO is a key molecule involved in astrocytic energy metabolism and lactate production. In the present study, we hypothesized there is an interaction between astrocytic lactate and central NO to negatively modulate water and sodium intake through the ANLS mechanism. The results showed that central Nω-nitro-L-arginine methyl ester (L-NAME, NO-synthase inhibition) induced an increase in water and sodium intake. These responses were attenuated by previous central microinjection of fluorocitrate (FCt, a reversible glial inhibitor). Interestingly, L-NAME-induced water and sodium intake were also decreased by previous microinjection of lactate but did not change after inhibition of the ANLS mechanism by α-cyano 4-hydroxycinnamic acid (α-CHCA), an inhibitor of the MCT lactate transporter. Our results suggest a central interaction between NO, glial cells, and lactate to modulate water and sodium intake.
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Affiliation(s)
| | | | | | | | | | | | - Josiane de Campos Cruz
- Biotechnology Center, Department of Biotechnology, Federal University of Paraiba, João Pessoa, Brazil; Department of Physiology and Pathology, Federal University of Paraiba, João Pessoa, Brazil; Department of Nutrition, Federal University of Paraiba, João Pessoa, Brazil; Department of Biotechnology, Federal University of Paraiba, João Pessoa, Brazil.
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12
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Structure-guided unlocking of Na X reveals a non-selective tetrodotoxin-sensitive cation channel. Nat Commun 2022; 13:1416. [PMID: 35301303 PMCID: PMC8931054 DOI: 10.1038/s41467-022-28984-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 02/16/2022] [Indexed: 12/19/2022] Open
Abstract
Unlike classical voltage-gated sodium (NaV) channels, NaX has been characterized as a voltage-insensitive, tetrodotoxin-resistant, sodium (Na+)-activated channel involved in regulating Na+ homeostasis. However, NaX remains refractory to functional characterization in traditional heterologous systems. Here, to gain insight into its atypical physiology, we determine structures of the human NaX channel in complex with the auxiliary β3-subunit. NaX reveals structural alterations within the selectivity filter, voltage sensor-like domains, and pore module. We do not identify an extracellular Na+-sensor or any evidence for a Na+-based activation mechanism in NaX. Instead, the S6-gate remains closed, membrane lipids fill the central cavity, and the domain III-IV linker restricts S6-dilation. We use protein engineering to identify three pore-wetting mutations targeting the hydrophobic S6-gate that unlock a robust voltage-insensitive leak conductance. This constitutively active NaX-QTT channel construct is non-selective among monovalent cations, inhibited by extracellular calcium, and sensitive to classical NaV channel blockers, including tetrodotoxin. Our findings highlight a functional diversity across the NaV channel scaffold, reshape our understanding of NaX physiology, and provide a template to demystify recalcitrant ion channels.
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13
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Zheng XQ, Wu YH, Huang JF, Wu AM. Neurophysiological mechanisms of cancer-induced bone pain. J Adv Res 2022; 35:117-127. [PMID: 35003797 PMCID: PMC8721251 DOI: 10.1016/j.jare.2021.06.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 05/23/2021] [Accepted: 06/08/2021] [Indexed: 12/16/2022] Open
Abstract
Background Cancer-induced Bone Pain (CIBP) is an important factor affecting their quality of life of cancer survivors. In addition, current clinical practice and scientific research suggest that neuropathic pain is a representative component of CIBP. However, given the variability of cancer conditions and the complexity of neuropathic pain, related mechanisms have been continuously supplemented but have not been perfected. Aim of Review Therefore, the current review highlights the latest progress in basic research on the field and proposes potential therapeutic targets, representative drugs and upcoming therapies. Key Scientific Concepts of Review Notably, factors such as central sensitization, neuroinflammation, glial cell activation and an acidic environment are considered to be related to neuropathic pain in CIBP. Nonetheless, further research is needed to ascertain the mechanism of CIBP in order to develop highly effective drugs. Moreover, more attention needs to be paid to the care of patients with advanced cancer.
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Affiliation(s)
- Xuan-Qi Zheng
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Zhejiang Provincial Key Laboratory of Orthopaedics, Wenzhou, Zhejiang, 325027, China
- Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - Yu-hao Wu
- Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - Jin-feng Huang
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Zhejiang Provincial Key Laboratory of Orthopaedics, Wenzhou, Zhejiang, 325027, China
- Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - Ai-Min Wu
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Zhejiang Provincial Key Laboratory of Orthopaedics, Wenzhou, Zhejiang, 325027, China
- Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
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14
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NODA M, MATSUDA T. Central regulation of body fluid homeostasis. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2022; 98:283-324. [PMID: 35908954 PMCID: PMC9363595 DOI: 10.2183/pjab.98.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Extracellular fluids, including blood, lymphatic fluid, and cerebrospinal fluid, are collectively called body fluids. The Na+ concentration ([Na+]) in body fluids is maintained at 135-145 mM and is broadly conserved among terrestrial animals. Homeostatic osmoregulation by Na+ is vital for life because severe hyper- or hypotonicity elicits irreversible organ damage and lethal neurological trauma. To achieve "body fluid homeostasis" or "Na homeostasis", the brain continuously monitors [Na+] in body fluids and controls water/salt intake and water/salt excretion by the kidneys. These physiological functions are primarily regulated based on information on [Na+] and relevant circulating hormones, such as angiotensin II, aldosterone, and vasopressin. In this review, we discuss sensing mechanisms for [Na+] and hormones in the brain that control water/salt intake behaviors, together with the responsible sensors (receptors) and relevant neural pathways. We also describe mechanisms in the brain by which [Na+] increases in body fluids activate the sympathetic neural activity leading to hypertension.
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Affiliation(s)
- Masaharu NODA
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa, Japan
- Correspondence should be addressed to: Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Kanagawa 226-8503, Japan (e-mail: )
| | - Takashi MATSUDA
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa, Japan
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15
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Signal Transduction of Mineralocorticoid and Angiotensin II Receptors in the Central Control of Sodium Appetite: A Narrative Review. Int J Mol Sci 2021; 22:ijms222111735. [PMID: 34769164 PMCID: PMC8584094 DOI: 10.3390/ijms222111735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/16/2021] [Accepted: 10/25/2021] [Indexed: 11/17/2022] Open
Abstract
Sodium appetite is an innate behavior occurring in response to sodium depletion that induces homeostatic responses such as the secretion of the mineralocorticoid hormone aldosterone from the zona glomerulosa of the adrenal cortex and the stimulation of the peptide hormone angiotensin II (ANG II). The synergistic action of these hormones signals to the brain the sodium appetite that represents the increased palatability for salt intake. This narrative review summarizes the main data dealing with the role of mineralocorticoid and ANG II receptors in the central control of sodium appetite. Appropriate keywords and MeSH terms were identified and searched in PubMed. References to original articles and reviews were examined, selected, and discussed. Several brain areas control sodium appetite, including the nucleus of the solitary tract, which contains aldosterone-sensitive HSD2 neurons, and the organum vasculosum lamina terminalis (OVLT) that contains ANG II-sensitive neurons. Furthermore, sodium appetite is under the control of signaling proteins such as mitogen-activated protein kinase (MAPK) and inositol 1,4,5-thriphosphate (IP3). ANG II stimulates salt intake via MAPK, while combined ANG II and aldosterone action induce sodium intake via the IP3 signaling pathway. Finally, aldosterone and ANG II stimulate OVLT neurons and suppress oxytocin secretion inhibiting the neuronal activity of the paraventricular nucleus, thus disinhibiting the OVLT activity to aldosterone and ANG II stimulation.
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16
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Hicks AI, Kobrinsky S, Zhou S, Yang J, Prager-Khoutorsky M. Anatomical Organization of the Rat Subfornical Organ. Front Cell Neurosci 2021; 15:691711. [PMID: 34552469 PMCID: PMC8450496 DOI: 10.3389/fncel.2021.691711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 08/10/2021] [Indexed: 11/14/2022] Open
Abstract
The subfornical organ (SFO) is a sensory circumventricular organ located along the anterodorsal wall of the third ventricle. SFO lacks a complete blood-brain barrier (BBB), and thus peripherally-circulating factors can penetrate the SFO parenchyma. These signals are detected by local neurons providing the brain with information from the periphery to mediate central responses to humoral signals and physiological stressors. Circumventricular organs are characterized by the presence of unique populations of non-neuronal cells, such as tanycytes and fenestrated endothelium. However, how these populations are organized within the SFO is not well understood. In this study, we used histological techniques to analyze the anatomical organization of the rat SFO and examined the distribution of neurons, fenestrated and non-fenestrated vasculature, tanycytes, ependymocytes, glia cells, and pericytes within its confines. Our data show that the shell of SFO contains non-fenestrated vasculature, while fenestrated capillaries are restricted to the medial-posterior core region of the SFO and associated with a higher BBB permeability. In contrast to non-fenestrated vessels, fenestrated capillaries are encased in a scaffold created by pericytes and embedded in a network of tanycytic processes. Analysis of c-Fos expression following systemic injections of angiotensin II or hypertonic NaCl reveals distinct neuronal populations responding to these stimuli. Hypertonic NaCl activates ∼13% of SFO neurons located in the shell. Angiotensin II-sensitive neurons represent ∼35% of SFO neurons and their location varies between sexes. Our study provides a comprehensive description of the organization of diverse cellular elements within the SFO, facilitating future investigations in this important brain area.
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Affiliation(s)
| | - Simona Kobrinsky
- Department of Physiology, McGill University, Montreal, QC, Canada
| | - Suijian Zhou
- Department of Physiology, McGill University, Montreal, QC, Canada
| | - Jieyi Yang
- Department of Physiology, McGill University, Montreal, QC, Canada
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17
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Dolivo D, Rodrigues A, Sun L, Li Y, Hou C, Galiano R, Hong SJ, Mustoe T. The Na x (SCN7A) channel: an atypical regulator of tissue homeostasis and disease. Cell Mol Life Sci 2021; 78:5469-5488. [PMID: 34100980 PMCID: PMC11072345 DOI: 10.1007/s00018-021-03854-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/15/2021] [Accepted: 05/08/2021] [Indexed: 12/15/2022]
Abstract
Within an articulately characterized family of ion channels, the voltage-gated sodium channels, exists a black sheep, SCN7A (Nax). Nax, in contrast to members of its molecular family, has lost its voltage-gated character and instead rapidly evolved a new function as a concentration-dependent sensor of extracellular sodium ions and subsequent signal transducer. As it deviates fundamentally in function from the rest of its family, and since the bulk of the impressive body of literature elucidating the pathology and biochemistry of voltage-gated sodium channels has been performed in nervous tissue, reports of Nax expression and function have been sparse. Here, we investigate available reports surrounding expression and potential roles for Nax activity outside of nervous tissue. With these studies as justification, we propose that Nax likely acts as an early sensor that detects loss of tissue homeostasis through the pathological accumulation of extracellular sodium and/or through endothelin signaling. Sensation of homeostatic aberration via Nax then proceeds to induce pathological tissue phenotypes via promotion of pro-inflammatory and pro-fibrotic responses, induced through direct regulation of gene expression or through the generation of secondary signaling molecules, such as lactate, that can operate in an autocrine or paracrine fashion. We hope that our synthesis of much of the literature investigating this understudied protein will inspire more research into Nax not simply as a biochemical oddity, but also as a potential pathophysiological regulator and therapeutic target.
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Affiliation(s)
- David Dolivo
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Adrian Rodrigues
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Lauren Sun
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Yingxing Li
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Chun Hou
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
- Department of Plastic and Cosmetic Surgery, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Robert Galiano
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Seok Jong Hong
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA.
- , 300 E. Superior St., Chicago, IL, 60611, USA.
| | - Thomas Mustoe
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA.
- , 737 N. Michigan Ave., Chicago, IL, 60611, USA.
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18
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Larval Zebrafish Use Olfactory Detection of Sodium and Chloride to Avoid Salt Water. Curr Biol 2020; 31:782-793.e3. [PMID: 33338431 DOI: 10.1016/j.cub.2020.11.051] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/17/2020] [Accepted: 11/18/2020] [Indexed: 12/19/2022]
Abstract
Salinity levels constrain the habitable environment of all aquatic organisms. Zebrafish are freshwater fish that cannot tolerate high-salt environments and would therefore benefit from neural mechanisms that enable the navigation of salt gradients to avoid high salinity. Yet zebrafish lack epithelial sodium channels, the primary conduit land animals use to taste sodium. This suggests fish may possess novel, undescribed mechanisms for salt detection. In the present study, we show that zebrafish indeed respond to small temporal increases in salt by reorienting more frequently. Further, we use calcium imaging techniques to identify the olfactory system as the primary sense used for salt detection, and we find that a specific subset of olfactory receptor neurons encodes absolute salinity concentrations by detecting monovalent anions and cations. In summary, our study establishes that zebrafish larvae have the ability to navigate and thus detect salinity gradients and that this is achieved through previously undescribed sensory mechanisms for salt detection.
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19
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Matsuda T, Hiyama TY, Kobayashi K, Kobayashi K, Noda M. Distinct CCK-positive SFO neurons are involved in persistent or transient suppression of water intake. Nat Commun 2020; 11:5692. [PMID: 33173030 PMCID: PMC7655816 DOI: 10.1038/s41467-020-19191-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 10/02/2020] [Indexed: 01/29/2023] Open
Abstract
The control of water-intake behavior is critical for life because an excessive water intake induces pathological conditions, such as hyponatremia or water intoxication. However, the brain mechanisms controlling water intake currently remain unclear. We previously reported that thirst-driving neurons (water neurons) in the subfornical organ (SFO) are cholecystokinin (CCK)-dependently suppressed by GABAergic interneurons under Na-depleted conditions. We herein show that CCK-producing excitatory neurons in the SFO stimulate the activity of GABAergic interneurons via CCK-B receptors. Fluorescence-microscopic Ca2+ imaging demonstrates two distinct subpopulations in CCK-positive neurons in the SFO, which are persistently activated under hyponatremic conditions or transiently activated in response to water drinking, respectively. Optical and chemogenetic silencings of the respective types of CCK-positive neurons both significantly increase water intake under water-repleted conditions. The present study thus reveals CCK-mediated neural mechanisms in the central nervous system for the control of water-intake behaviors. Water intake is critical to our life, and the subfornical organ in the brain involved in the control of this behavior. Here, the authors reveal that two distinct groups of CCK-producing neurons in the SFO suppress water intake according to the physiological condition or water-intake stimulus.
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Affiliation(s)
- Takashi Matsuda
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa, 226-8503, Japan.,Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, 444-8787, Japan
| | - Takeshi Y Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, 444-8787, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8585, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Fukushima, 960-1295, Japan
| | - Masaharu Noda
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa, 226-8503, Japan. .,Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, 444-8787, Japan.
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20
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Pool AH, Wang T, Stafford DA, Chance RK, Lee S, Ngai J, Oka Y. The cellular basis of distinct thirst modalities. Nature 2020; 588:112-117. [PMID: 33057193 PMCID: PMC7718410 DOI: 10.1038/s41586-020-2821-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 07/16/2020] [Indexed: 12/16/2022]
Abstract
Fluid intake is an essential innate behavior mainly caused by two distinct types of thirst1–3. Increased blood osmolality induces osmotic thirst that drives animals to consume pure water. Conversely, the loss of body fluid induces hypovolemic thirst in which animals seek both water and minerals (salts) to recover blood volume. Circumventricular organs (CVOs) in the lamina terminalis (LT) are critical sites for sensing both types of thirst-inducing stimuli4–6. However, how different thirst modalities are encoded in the brain remains unknown. Here, we employed stimulus to cell-type mapping using single-cell RNA-seq (scRNA-seq) to determine the cellular substrate underlying distinct types of thirst. These studies revealed diverse excitatory and inhibitory neuron types in each CVO structure. Among them, we show that unique combinations of neuron types are activated under osmotic and hypovolemic stresses. These results elucidate the cellular logic underlying distinct thirst modalities. Furthermore, optogenetic gain-of-function in thirst-modality-specific cell types recapitulated water-specific and non-specific fluid appetite caused by the two distinct dipsogenic stimuli. Taken together, this study demonstrates that thirst is a multimodal physiological state, and that different thirst states are mediated by specific neuron types in the mammalian brain.
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Affiliation(s)
- Allan-Hermann Pool
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Tongtong Wang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.,College of Life Sciences, Nankai University, Tianjin, China
| | - David A Stafford
- Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Rebecca K Chance
- Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Sangjun Lee
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - John Ngai
- Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA, USA.,National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Yuki Oka
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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21
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Sakuta H, Lin CH, Hiyama TY, Matsuda T, Yamaguchi K, Shigenobu S, Kobayashi K, Noda M. SLC9A4 in the organum vasculosum of the lamina terminalis is a [Na+] sensor for the control of water intake. Pflugers Arch 2020; 472:609-624. [DOI: 10.1007/s00424-020-02389-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/17/2020] [Accepted: 04/28/2020] [Indexed: 12/19/2022]
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22
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Sakuta H, Lin CH, Yamada M, Kita Y, Tokuoka SM, Shimizu T, Noda M. Nax-positive glial cells in the organum vasculosum laminae terminalis produce epoxyeicosatrienoic acids to induce water intake in response to increases in [Na+] in body fluids. Neurosci Res 2020; 154:45-51. [DOI: 10.1016/j.neures.2019.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 04/24/2019] [Accepted: 05/27/2019] [Indexed: 01/06/2023]
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23
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Ch'ng SS, Lawrence AJ. The subfornical organ in sodium appetite: Recent insights. Neuropharmacology 2019; 154:107-113. [DOI: 10.1016/j.neuropharm.2018.08.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 08/10/2018] [Accepted: 08/11/2018] [Indexed: 12/17/2022]
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24
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Wang Y, Sabbagh MF, Gu X, Rattner A, Williams J, Nathans J. Beta-catenin signaling regulates barrier-specific gene expression in circumventricular organ and ocular vasculatures. eLife 2019; 8:43257. [PMID: 30932813 PMCID: PMC6443350 DOI: 10.7554/elife.43257] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 03/17/2019] [Indexed: 12/29/2022] Open
Abstract
The brain, spinal cord, and retina are supplied by capillaries that do not permit free diffusion of molecules between serum and parenchyma, a property that defines the blood-brain and blood-retina barriers. Exceptions to this pattern are found in circumventricular organs (CVOs), small midline brain structures that are supplied by high permeability capillaries. In the eye and brain, high permeability capillaries are also present in the choriocapillaris, which supplies the retinal pigment epithelium and photoreceptors, and the ciliary body and choroid plexus, the sources of aqueous humor and cerebrospinal fluid, respectively. We show here that (1) endothelial cells in these high permeability vascular systems have very low beta-catenin signaling compared to barrier-competent endothelial cells, and (2) elevating beta-catenin signaling leads to a partial conversion of permeable endothelial cells to a barrier-type state. In one CVO, the area postrema, high permeability is maintained, in part, by local production of Wnt inhibitory factor-1.
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Affiliation(s)
- Yanshu Wang
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Mark F Sabbagh
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Xiaowu Gu
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Amir Rattner
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
| | - John Williams
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States
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25
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Nomura K, Hiyama TY, Sakuta H, Matsuda T, Lin CH, Kobayashi K, Kobayashi K, Kuwaki T, Takahashi K, Matsui S, Noda M. [Na +] Increases in Body Fluids Sensed by Central Na x Induce Sympathetically Mediated Blood Pressure Elevations via H +-Dependent Activation of ASIC1a. Neuron 2018; 101:60-75.e6. [PMID: 30503172 DOI: 10.1016/j.neuron.2018.11.017] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 10/08/2018] [Accepted: 11/08/2018] [Indexed: 02/07/2023]
Abstract
Increases in sodium concentrations ([Na+]) in body fluids elevate blood pressure (BP) by enhancing sympathetic nerve activity (SNA). However, the mechanisms by which information on increased [Na+] is translated to SNA have not yet been elucidated. We herein reveal that sympathetic activation leading to BP increases is not induced by mandatory high salt intakes or the intraperitoneal/intracerebroventricular infusions of hypertonic NaCl solutions in Nax-knockout mice in contrast to wild-type mice. We identify Nax channels expressed in specific glial cells in the organum vasculosum lamina terminalis (OVLT) as the sensors detecting increases in [Na+] in body fluids and show that OVLT neurons projecting to the paraventricular nucleus (PVN) are activated via acid-sensing ion channel 1a (ASIC1a) by H+ ions exported from Nax-positive glial cells. The present results provide an insight into the neurogenic mechanisms responsible for salt-induced BP elevations.
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Affiliation(s)
- Kengo Nomura
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan
| | - Takeshi Y Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan; School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
| | - Hiraki Sakuta
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan; School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
| | - Takashi Matsuda
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan
| | - Chia-Hao Lin
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Tomoyuki Kuwaki
- Department of Physiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
| | - Kunihiko Takahashi
- Department of Biostatistics, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan
| | - Shigeyuki Matsui
- Department of Biostatistics, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan
| | - Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan; School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan; Research Center for Cell Biology, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan.
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26
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Abstract
Every cell within living organisms actively maintains an intracellular Na+ concentration that is 10-12 times lower than the extracellular concentration. The cells then utilize this transmembrane Na+ concentration gradient as a driving force to produce electrical signals, sometimes in the form of action potentials. The protein family comprising voltage-gated sodium channels (NaVs) is essential for such signaling and enables cells to change their status in a regenerative manner and to rapidly communicate with one another. NaVs were first predicted in squid and were later identified through molecular biology in the electric eel. Since then, these proteins have been discovered in organisms ranging from bacteria to humans. Recent research has succeeded in decoding the amino acid sequences of a wide variety of NaV family members, as well as the three-dimensional structures of some. These studies and others have uncovered several of the major steps in the functional and structural transition of NaV proteins that has occurred along the course of the evolutionary history of organisms. Here we present an overview of the molecular evolutionary innovations that established present-day NaV α subunits and discuss their contribution to the evolutionary changes in animal bodies.
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Affiliation(s)
- Atsuo Nishino
- Department of Biology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki, Aomori, Japan.
| | - Yasushi Okamura
- Integrative Physiology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
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27
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Abstract
Fierce debate has developed whether low-sodium intake, like high-sodium intake, could be associated with adverse outcome. The debate originates in earlier epidemiological studies associating high-sodium intake with high blood pressure and more recent studies demonstrating a higher cardiovascular event rate with both low- and high-sodium intake. This brings into question whether we entirely understand the consequences of high- and (very) low-sodium intake for the systemic hemodynamics, the kidney function, the vascular wall, the immune system, and the brain. Evolutionarily, sodium retention mechanisms in the context of low dietary sodium provided a survival advantage and are highly conserved, exemplified by the renin-angiotensin system. What is the potential for this sodium-retaining mechanism to cause harm? In this paper, we will consider current views on how a sodium load is handled, visiting aspects including the effect of sodium on the vessel wall, the sympathetic nervous system, the brain renin-angiotensin system, the skin as "third compartment" coupling to vascular endothelial growth factor C, and the kidneys. From these perspectives, several mechanisms can be envisioned whereby a low-sodium diet could potentially cause harm, including the renin-angiotensin system and the sympathetic nervous system. Altogether, the uncertainties preclude a unifying model or practical clinical guidance regarding the effects of a low-sodium diet for an individual. There is a very strong need for fundamental and translational studies to enhance the understanding of the potential adverse consequences of low-salt intake as an initial step to facilitate better clinical guidance.
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Affiliation(s)
- Branko Braam
- Department of Medicine, University of Alberta, Edmonton, AB, Canada. .,Department of Physiology, University of Alberta, Edmonton, AB, Canada. .,Department of Medicine / Division of Nephrology and Immunology, University of Alberta Hospital, 11-132 CSB Clinical Sciences Building, Edmonton, AB, T6G 2G3, Canada.
| | - Xiaohua Huang
- Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - William A Cupples
- Biomedical Physiology & Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - Shereen M Hamza
- Department of Medicine, University of Alberta, Edmonton, AB, Canada.,Department of Physiology, University of Alberta, Edmonton, AB, Canada
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28
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Abstract
Water intake is one of the most basic physiological responses and is essential to sustain life. The perception of thirst has a critical role in controlling body fluid homeostasis and if neglected or dysregulated can lead to life-threatening pathologies. Clear evidence suggests that the perception of thirst occurs in higher-order centres, such as the anterior cingulate cortex (ACC) and insular cortex (IC), which receive information from midline thalamic relay nuclei. Multiple brain regions, notably circumventricular organs such as the organum vasculosum lamina terminalis (OVLT) and subfornical organ (SFO), monitor changes in blood osmolality, solute load and hormone circulation and are thought to orchestrate appropriate responses to maintain extracellular fluid near ideal set points by engaging the medial thalamic-ACC/IC network. Thirst has long been thought of as a negative homeostatic feedback response to increases in blood solute concentration or decreases in blood volume. However, emerging evidence suggests a clear role for thirst as a feedforward adaptive anticipatory response that precedes physiological challenges. These anticipatory responses are promoted by rises in core body temperature, food intake (prandial) and signals from the circadian clock. Feedforward signals are also important mediators of satiety, inhibiting thirst well before the physiological state is restored by fluid ingestion. In this Review, we discuss the importance of thirst for body fluid balance and outline our current understanding of the neural mechanisms that underlie the various types of homeostatic and anticipatory thirst.
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Affiliation(s)
- Claire Gizowski
- Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre and Montreal General Hospital, 1650 Cedar Avenue, Montreal H3G1A4, Canada
| | - Charles W Bourque
- Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre and Montreal General Hospital, 1650 Cedar Avenue, Montreal H3G1A4, Canada
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Nakamura-Utsunomiya A, Hiyama TY, Okada S, Noda M, Kobayashi M. Characteristic clinical features of adipsic hypernatremia patients with subfornical organ-targeting antibody. Clin Pediatr Endocrinol 2017; 26:197-205. [PMID: 29026268 PMCID: PMC5627220 DOI: 10.1297/cpe.26.197] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 04/15/2017] [Indexed: 12/11/2022] Open
Abstract
Adipsic hypernatremia is a rare disease presenting as persistent hypernatremia with disturbance of thirst regulation and hypothalamic dysfunction. As a result of congenital disease, tumors, or inflammation, most cases are accompanied by structural abnormalities in the hypothalamic-pituitary area. While cases with no hypothalamic-pituitary structural lesion have been reported, their etiology has not been elucidated. Recently, we reported three patients with adipsic hypernatremia whose serum-derived immunoglobulin (Ig) specifically reacted with mouse subfornical organ (SFO) tissue. As one of the circumventricular organs (CVOs) that form a sensory interface between the blood and brain, the SFO is a critical site for generating physiological responses to dehydration and hypernatremia. Intravenous injection of the patient's Ig fraction induced hypernatremia in mice, along with inflammation and apoptosis in the SFO. These results support a new autoimmunity-related mechanism for inducing adipsic hypernatremia without demonstrable hypothalamic-pituitary structural lesions. In this review, we aim to highlight the characteristic clinical features of these patients, in addition to etiological mechanisms related to SFO function. These findings may be useful for diagnosing adipsic hypernatremia caused by an autoimmune response to the SFO, and support development of new strategies for prevention and treatment.
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Affiliation(s)
| | - Takeshi Y Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology (NIBB), Aichi, Japan.,School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Aichi, Japan
| | - Satoshi Okada
- Department of Pediatrics, Hiroshima University Hospital, Hiroshima, Japan
| | - Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology (NIBB), Aichi, Japan.,School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Aichi, Japan
| | - Masao Kobayashi
- Department of Pediatrics, Hiroshima University Hospital, Hiroshima, Japan
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Prager-Khoutorsky M, Choe KY, Levi DI, Bourque CW. Role of Vasopressin in Rat Models of Salt-Dependent Hypertension. Curr Hypertens Rep 2017; 19:42. [PMID: 28451854 DOI: 10.1007/s11906-017-0741-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE OF REVIEW Dietary salt intake increases both plasma sodium and osmolality and therefore increases vasopressin (VP) release from the neurohypophysis. Although this effect could increase blood pressure by inducing fluid reabsorption and vasoconstriction, acute activation of arterial baroreceptors inhibits VP neurons via GABAA receptors to oppose high blood pressure. Here we review recent findings demonstrating that this protective mechanism fails during chronic high salt intake in rats. RECENT FINDINGS Two recent studies showed that chronic high sodium intake causes an increase in intracellular chloride concentration in VP neurons. This effect causes GABAA receptors to become excitatory and leads to the emergence of VP-dependent hypertension. One study showed that the increase in intracellular chloride was provoked by a decrease in the expression of the chloride exporter KCC2 mediated by local secretion of brain-derived neurotrophic factor and activation of TrkB receptors. Prolonged high dietary salt intake can cause pathological plasticity in a central homeostatic circuit that controls VP secretion and thereby contribute to peripheral vasoconstriction and hypertension.
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Affiliation(s)
- Masha Prager-Khoutorsky
- Department of Physiology, McGill University, McIntyre Medical Sciences Bldg., 3655 Promenade Sir-William Osler, Montreal, QC, H3G 1Y6, Canada
| | - Katrina Y Choe
- 2309 Gonda Neuroscience and Genetics Research Center, UCLA Department of Neurology, 695 Charles E. Young Dr. South, Los Angeles, CA, 90095, USA
| | - David I Levi
- Centre for Research in Neuroscience, Research Institute of the McGill University Health Center, Montreal General Hospital, 1650 Cedar Avenue, Montreal, QC, H3G 1A4, Canada
| | - Charles W Bourque
- Centre for Research in Neuroscience, Research Institute of the McGill University Health Center, Montreal General Hospital, 1650 Cedar Avenue, Montreal, QC, H3G 1A4, Canada.
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Antunes VR. Hypertonic NaCl versus osmotic stimuli: distinct OVLT neurones can sense the difference to control sympathetic outflow and blood pressure. J Physiol 2017; 595:6089-6090. [PMID: 28766715 DOI: 10.1113/jp274868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- V R Antunes
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
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Kinsman BJ, Browning KN, Stocker SD. NaCl and osmolarity produce different responses in organum vasculosum of the lamina terminalis neurons, sympathetic nerve activity and blood pressure. J Physiol 2017; 595:6187-6201. [PMID: 28678348 DOI: 10.1113/jp274537] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Accepted: 06/21/2017] [Indexed: 01/12/2023] Open
Abstract
KEY POINTS Changes in extracellular osmolarity stimulate thirst and vasopressin secretion through a central osmoreceptor; however, central infusion of hypertonic NaCl produces a greater sympathoexcitatory and pressor response than infusion of hypertonic mannitol/sorbitol. Neurons in the organum vasculosum of the lamina terminalis (OVLT) sense changes in extracellular osmolarity and NaCl. In this study, we discovered that intracerebroventricular infusion or local OVLT injection of hypertonic NaCl increases lumbar sympathetic nerve activity, adrenal sympathetic nerve activity and arterial blood pressure whereas equi-osmotic mannitol/sorbitol did not alter any variable. In vitro whole-cell recordings demonstrate the majority of OVLT neurons are responsive to hypertonic NaCl or mannitol. However, hypertonic NaCl stimulates a greater increase in discharge frequency than equi-osmotic mannitol. Intracarotid or intracerebroventricular infusion of hypertonic NaCl evokes a greater increase in OVLT neuronal discharge frequency than equi-osmotic sorbitol. Collectively, these novel data suggest that subsets of OVLT neurons respond differently to hypertonic NaCl versus osmolarity and subsequently regulate body fluid homeostasis. These responses probably reflect distinct cellular mechanisms underlying NaCl- versus osmo-sensing. ABSTRACT Systemic or central infusion of hypertonic NaCl and other osmolytes readily stimulate thirst and vasopressin secretion. In contrast, central infusion of hypertonic NaCl produces a greater increase in arterial blood pressure (ABP) than equi-osmotic mannitol/sorbitol. Although these responses depend on neurons in the organum vasculosum of the lamina terminalis (OVLT), these observations suggest OVLT neurons may sense or respond differently to hypertonic NaCl versus osmolarity. The purpose of this study was to test this hypothesis in Sprague-Dawley rats. First, intracerebroventricular (icv) infusion (5 μl/10 min) of 1.0 m NaCl produced a significantly greater increase in lumbar sympathetic nerve activity (SNA), adrenal SNA and ABP than equi-osmotic sorbitol (2.0 osmol l-1 ). Second, OVLT microinjection (20 nl) of 1.0 m NaCl significantly raised lumbar SNA, adrenal SNA and ABP. Equi-osmotic sorbitol did not alter any variable. Third, in vitro whole-cell recordings demonstrate that 50% (18/36) of OVLT neurons display an increased discharge to both hypertonic NaCl (+7.5 mm) and mannitol (+15 mm). Of these neurons, 56% (10/18) displayed a greater discharge response to hypertonic NaCl vs mannitol. Fourth, in vivo single-unit recordings revealed that intracarotid injection of hypertonic NaCl produced a concentration-dependent increase in OVLT cell discharge, lumbar SNA and ABP. The responses to equi-osmotic infusions of hypertonic sorbitol were significantly smaller. Lastly, icv infusion of 0.5 m NaCl produced significantly greater increases in OVLT discharge and ABP than icv infusion of equi-osmotic sorbitol. Collectively, these findings indicate NaCl and osmotic stimuli produce different responses across OVLT neurons and may represent distinct cellular processes to regulate thirst, vasopressin secretion and autonomic function.
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Affiliation(s)
- Brian J Kinsman
- Department of Medicine, Division of Renal-Electrolyte, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA.,Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA, 17033, USA
| | - Kirsteen N Browning
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA, 17033, USA
| | - Sean D Stocker
- Department of Medicine, Division of Renal-Electrolyte, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
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Agassandian K, Grobe JL, Liu X, Agassandian M, Thompson AP, Sigmund CD, Cassell MD. Evidence for intraventricular secretion of angiotensinogen and angiotensin by the subfornical organ using transgenic mice. Am J Physiol Regul Integr Comp Physiol 2017; 312:R973-R981. [PMID: 28490451 PMCID: PMC5495920 DOI: 10.1152/ajpregu.00511.2016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 05/03/2017] [Accepted: 05/03/2017] [Indexed: 01/05/2023]
Abstract
Direct intracerebroventricular injection of angiotensin II (ANG II) causes increases in blood pressure and salt and water intake, presumably mimicking an effect mediated by an endogenous mechanism. The subfornical organ (SFO) is a potential source of cerebrospinal fluid (CSF), ANG I, and ANG II, and thus we hypothesized that the SFO has a secretory function. Endogenous levels of angiotensinogen (AGT) and renin are very low in the brain. We therefore examined the immunohistochemical localization of angiotensin peptides and AGT in the SFO, and AGT in the CSF in two transgenic models that overexpress either human AGT (A+ mice), or both human AGT (hAGT) and human renin (SRA mice) in the brain. Measurements were made at baseline and following volumetric depletion of CSF. Ultrastructural analysis with immunoelectron microscopy revealed that superficially located ANG I/ANG II and AGT immunoreactive cells in the SFO were vacuolated and opened directly into the ventricle. Withdrawal of CSF produced an increase in AGT in the CSF that was accompanied by a large decline in AGT immunoreactivity within SFO cells. Our data provide support for the hypothesis that the SFO is a secretory organ that releases AGT and possibly ANG I/ANG II into the ventricle at least under conditions when genes that control the renin-angiotensin system are overexpressed in mice.
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Affiliation(s)
- Khristofor Agassandian
- Department of Anatomy and Cell Biology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Justin L Grobe
- UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - Xuebo Liu
- UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - Marianna Agassandian
- Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Anthony P Thompson
- Department of Anatomy and Cell Biology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa.,UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Curt D Sigmund
- UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa; .,Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - Martin D Cassell
- Department of Anatomy and Cell Biology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa.,UIHC Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
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Böger CA, Gorski M, McMahon GM, Xu H, Chang YPC, van der Most PJ, Navis G, Nolte IM, de Borst MH, Zhang W, Lehne B, Loh M, Tan ST, Boerwinkle E, Grams ME, Sekula P, Li M, Wilmot B, Moon JG, Scheet P, Cucca F, Xiao X, Lyytikäinen LP, Delgado G, Grammer TB, Kleber ME, Sedaghat S, Rivadeneira F, Corre T, Kutalik Z, Bergmann S, Nielson CM, Srikanth P, Teumer A, Müller-Nurasyid M, Brockhaus AC, Pfeufer A, Rathmann W, Peters A, Matsumoto M, de Andrade M, Atkinson EJ, Robinson-Cohen C, de Boer IH, Hwang SJ, Heid IM, Gögele M, Concas MP, Tanaka T, Bandinelli S, Nalls MA, Singleton A, Tajuddin SM, Adeyemo A, Zhou J, Doumatey A, McWeeney S, Murabito J, Franceschini N, Flessner M, Shlipak M, Wilson JG, Chen G, Rotimi CN, Zonderman AB, Evans MK, Ferrucci L, Devuyst O, Pirastu M, Shuldiner A, Hicks AA, Pramstaller PP, Kestenbaum B, Kardia SLR, Turner ST, Study LC, Briske TE, Gieger C, Strauch K, Meisinger C, Meitinger T, Völker U, Nauck M, Völzke H, Vollenweider P, Bochud M, Waeber G, Kähönen M, Lehtimäki T, März W, Dehghan A, Franco OH, Uitterlinden AG, Hofman A, Taylor HA, Chambers JC, Kooner JS, Fox CS, Hitzemann R, Orwoll ES, Pattaro C, Schlessinger D, Köttgen A, Snieder H, Parsa A, Cohen DM. NFAT5 and SLC4A10 Loci Associate with Plasma Osmolality. J Am Soc Nephrol 2017; 28:2311-2321. [PMID: 28360221 DOI: 10.1681/asn.2016080892] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 02/02/2017] [Indexed: 12/20/2022] Open
Abstract
Disorders of water balance, an excess or deficit of total body water relative to body electrolyte content, are common and ascertained by plasma hypo- or hypernatremia, respectively. We performed a two-stage genome-wide association study meta-analysis on plasma sodium concentration in 45,889 individuals of European descent (stage 1 discovery) and 17,637 additional individuals of European descent (stage 2 replication), and a transethnic meta-analysis of replicated single-nucleotide polymorphisms in 79,506 individuals (63,526 individuals of European descent, 8765 individuals of Asian Indian descent, and 7215 individuals of African descent). In stage 1, we identified eight loci associated with plasma sodium concentration at P<5.0 × 10-6 Of these, rs9980 at NFAT5 replicated in stage 2 meta-analysis (P=3.1 × 10-5), with combined stages 1 and 2 genome-wide significance of P=5.6 × 10-10 Transethnic meta-analysis further supported the association at rs9980 (P=5.9 × 10-12). Additionally, rs16846053 at SLC4A10 showed nominally, but not genome-wide, significant association in combined stages 1 and 2 meta-analysis (P=6.7 × 10-8). NFAT5 encodes a ubiquitously expressed transcription factor that coordinates the intracellular response to hypertonic stress but was not previously implicated in the regulation of systemic water balance. SLC4A10 encodes a sodium bicarbonate transporter with a brain-restricted expression pattern, and variant rs16846053 affects a putative intronic NFAT5 DNA binding motif. The lead variants for NFAT5 and SLC4A10 are cis expression quantitative trait loci in tissues of the central nervous system and relevant to transcriptional regulation. Thus, genetic variation in NFAT5 and SLC4A10 expression and function in the central nervous system may affect the regulation of systemic water balance.
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Affiliation(s)
- Carsten A Böger
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Mathias Gorski
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Gearoid M McMahon
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Huichun Xu
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Yen-Pei C Chang
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Peter J van der Most
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Gerjan Navis
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Ilja M Nolte
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Martin H de Borst
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Weihua Zhang
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Benjamin Lehne
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Marie Loh
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Sian-Tsung Tan
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Eric Boerwinkle
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Morgan E Grams
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Peggy Sekula
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Man Li
- Due to the number of contributing authors, the affiliations are listed in the supplemental material.
| | - Beth Wilmot
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - James G Moon
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Paul Scheet
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Francesco Cucca
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Xiangjun Xiao
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Leo-Pekka Lyytikäinen
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Graciela Delgado
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Tanja B Grammer
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Marcus E Kleber
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Sanaz Sedaghat
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Fernando Rivadeneira
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Tanguy Corre
- Due to the number of contributing authors, the affiliations are listed in the supplemental material.
| | - Zoltan Kutalik
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Sven Bergmann
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Carrie M Nielson
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Priya Srikanth
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Alexander Teumer
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Martina Müller-Nurasyid
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Anne Catharina Brockhaus
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Arne Pfeufer
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Wolfgang Rathmann
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Annette Peters
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Martha Matsumoto
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Mariza de Andrade
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Elizabeth J Atkinson
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Cassianne Robinson-Cohen
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Ian H de Boer
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Shih-Jen Hwang
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Iris M Heid
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Martin Gögele
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Maria Pina Concas
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Toshiko Tanaka
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Stefania Bandinelli
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Mike A Nalls
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Andrew Singleton
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Salman M Tajuddin
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Adebowale Adeyemo
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Jie Zhou
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Ayo Doumatey
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Shannon McWeeney
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Joanne Murabito
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Nora Franceschini
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Michael Flessner
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Michael Shlipak
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - James G Wilson
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Guanjie Chen
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Charles N Rotimi
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Alan B Zonderman
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Michele K Evans
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Luigi Ferrucci
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Olivier Devuyst
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Mario Pirastu
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Alan Shuldiner
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Andrew A Hicks
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Peter Paul Pramstaller
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Bryan Kestenbaum
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Sharon L R Kardia
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Stephen T Turner
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - LifeLines Cohort Study
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Tamara Ellefson Briske
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Christian Gieger
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Konstantin Strauch
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Christa Meisinger
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Thomas Meitinger
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Uwe Völker
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Matthias Nauck
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Henry Völzke
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Peter Vollenweider
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Murielle Bochud
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Gerard Waeber
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Mika Kähönen
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Terho Lehtimäki
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Winfried März
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Abbas Dehghan
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Oscar H Franco
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Andre G Uitterlinden
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Albert Hofman
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Herman A Taylor
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - John C Chambers
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Jaspal S Kooner
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Caroline S Fox
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Robert Hitzemann
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Eric S Orwoll
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Cristian Pattaro
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - David Schlessinger
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Anna Köttgen
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Harold Snieder
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - Afshin Parsa
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
| | - David M Cohen
- Due to the number of contributing authors, the affiliations are listed in the supplemental material
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Jiang XZ, Pei YX, Lei W, Wang KY, Shang F, Jiang HB, Wang JJ. Characterization of an insect heterodimeric voltage-gated sodium channel with unique alternative splicing mode. Comp Biochem Physiol B Biochem Mol Biol 2017; 203:149-158. [DOI: 10.1016/j.cbpb.2016.10.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 10/20/2016] [Accepted: 10/31/2016] [Indexed: 12/22/2022]
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Cancelliere NM, Ferguson AV. Subfornical organ neurons integrate cardiovascular and metabolic signals. Am J Physiol Regul Integr Comp Physiol 2016; 312:R253-R262. [PMID: 28003212 DOI: 10.1152/ajpregu.00423.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 12/20/2016] [Accepted: 12/20/2016] [Indexed: 12/13/2022]
Abstract
The subfornical organ (SFO) is a critical circumventricular organ involved in the control of cardiovascular and metabolic homeostasis. Despite the plethora of circulating signals continuously sensed by the SFO, studies investigating how these signals are integrated are lacking. In this study, we use patch-clamp techniques to investigate how the traditionally classified "cardiovascular" hormone ANG II, "metabolic" hormone CCK and "metabolic" signal glucose interact and are integrated in the SFO. Sequential bath application of CCK (10 nM) and ANG (10 nM) onto dissociated SFO neurons revealed that 63% of responsive SFO neurons depolarized to both CCK and ANG; 25% depolarized to ANG only; and 12% hyperpolarized to CCK only. We next investigated the effects of glucose by incubating and recording neurons in either hypoglycemic, normoglycemic, or hyperglycemic conditions and comparing the proportions of responses to ANG (n = 55) or CCK (n = 83) application in each condition. A hyperglycemic environment was associated with a larger proportion of depolarizing responses to ANG (χ2, P < 0.05), and a smaller proportion of depolarizing responses along with a larger proportion of hyperpolarizing responses to CCK (χ2, P < 0.01). Our data demonstrate that SFO neurons excited by CCK are also excited by ANG and that glucose environment affects the responsiveness of neurons to both of these hormones, highlighting the ability of SFO neurons to integrate multiple metabolic and cardiovascular signals. These findings have important implications for this structure's role in the control of various autonomic functions during hyperglycemia.
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Affiliation(s)
| | - Alastair V Ferguson
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
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Matsuda T, Hiyama TY, Niimura F, Matsusaka T, Fukamizu A, Kobayashi K, Kobayashi K, Noda M. Distinct neural mechanisms for the control of thirst and salt appetite in the subfornical organ. Nat Neurosci 2016; 20:230-241. [PMID: 27991901 DOI: 10.1038/nn.4463] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 11/17/2016] [Indexed: 12/20/2022]
Abstract
Body fluid conditions are continuously monitored in the brain to regulate thirst and salt-appetite sensations. Angiotensin II drives both thirst and salt appetite; however, the neural mechanisms underlying selective water- and/or salt-intake behaviors remain unknown. Using optogenetics, we show that thirst and salt appetite are driven by distinct groups of angiotensin II receptor type 1a-positive excitatory neurons in the subfornical organ. Neurons projecting to the organum vasculosum lamina terminalis control water intake, while those projecting to the ventral part of the bed nucleus of the stria terminalis control salt intake. Thirst-driving neurons are suppressed under sodium-depleted conditions through cholecystokinin-mediated activation of GABAergic neurons. In contrast, the salt appetite-driving neurons were suppressed under dehydrated conditions through activation of another population of GABAergic neurons by Nax signals. These distinct mechanisms in the subfornical organ may underlie the selective intakes of water and/or salt and may contribute to body fluid homeostasis.
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Affiliation(s)
- Takashi Matsuda
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, Japan.,School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| | - Takeshi Y Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, Japan.,School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| | - Fumio Niimura
- Department of Pediatrics, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Taiji Matsusaka
- Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Akiyoshi Fukamizu
- Life Science Center, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Ibaraki, Japan.,Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, Japan.,School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
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38
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Hiyama TY, Noda M. Sodium sensing in the subfornical organ and body-fluid homeostasis. Neurosci Res 2016; 113:1-11. [PMID: 27521454 DOI: 10.1016/j.neures.2016.07.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 07/22/2016] [Accepted: 07/28/2016] [Indexed: 01/28/2023]
Abstract
The brain monitors conditions of body fluids and levels of circulating neuroactive factors to maintain the systemic homeostasis. Unlike most regions in the brain, circumventricular organs (CVOs) lack the blood-brain barrier, and serve as the sensing center. Among the CVOs, the subfornical organ (SFO) is the sensing site of Na+ levels in body fluids to control water and salt intake. The SFO harbors neuronal cell bodies with a variety of hormone receptors and innervates many brain loci. In addition, the SFO harbors specialized glial cells (astrocytes and ependymal cells) expressing Nax, a Na+-level-sensitive sodium channel. These glial cells wrap a specific population of neurons with their processes, and control the firing activities of the neurons by gliotransmitters, such as lactate and epoxyeicosatrienoic acids (EETs), relevant to water/salt-intake behaviors. Recent advances in the understanding of physiological functions of the SFO are reviewed herein with a focus on the Na+-sensing mechanism by Nax.
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Affiliation(s)
- Takeshi Y Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, and School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan.
| | - Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, and School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
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Hiyama TY, Utsunomiya AN, Matsumoto M, Fujikawa A, Lin CH, Hara K, Kagawa R, Okada S, Kobayashi M, Ishikawa M, Anzo M, Cho H, Takayasu S, Nigawara T, Daimon M, Sato T, Terui K, Ito E, Noda M. Adipsic hypernatremia without hypothalamic lesions accompanied by autoantibodies to subfornical organ. Brain Pathol 2016; 27:323-331. [PMID: 27338632 DOI: 10.1111/bpa.12409] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/14/2016] [Indexed: 11/28/2022] Open
Abstract
Adipsic (or essential) hypernatremia is a rare hypernatremia caused by a deficiency in thirst regulation and vasopressin release. In 2010, we reported a case in which autoantibodies targeting the sensory circumventricular organs (sCVOs) caused adipsic hypernatremia without hypothalamic structural lesions demonstrable by magnetic resonance imaging (MRI); sCVOs include the subfornical organ (SFO) and organum vasculosum of the lamina terminalis (OVLT), which are centers for the monitoring of body-fluid conditions and the control of water and salt intakes, and harbor neurons innervating hypothalamic nuclei for vasopressin release. We herein report three newly identified patients (3- to 8-year-old girls on the first visit) with similar symptoms. The common features of the patients were extensive hypernatremia without any sensation of thirst and defects in vasopressin response to serum hypertonicity. Despite these features, we could not detect any hypothalamic structural lesions by MRI. Immunohistochemical analyses using the sera of the three patients revealed that antibodies specifically reactive to the mouse SFO were present in the sera of all cases; in one case, the antibodies also reacted with the mouse OVLT. The immunoglobulin (Ig) fraction of serum obtained from one patient was intravenously injected into wild-type mice to determine whether the mice developed similar symptoms. Mice injected with a patient's Ig showed abnormalities in water/salt intake, vasopressin release, and diuresis, which resultantly developed hypernatremia. Prominent cell death and infiltration of reactive microglia was observed in the SFO of these mice. Thus, autoimmune destruction of the SFO may be the cause of the adipsic hypernatremia. This study provides a possible explanation for the pathogenesis of adipsic hypernatremia without demonstrable hypothalamus-pituitary lesions.
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Affiliation(s)
- Takeshi Y Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology (NIBB), Okazaki, Aichi, 444-8787, Japan.,School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, 444-8787, Japan
| | - Akari N Utsunomiya
- Department of Pediatrics, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Hiroshima, 734-8551, Japan
| | - Masahito Matsumoto
- Division of Molecular Neurobiology, National Institute for Basic Biology (NIBB), Okazaki, Aichi, 444-8787, Japan
| | - Akihiro Fujikawa
- Division of Molecular Neurobiology, National Institute for Basic Biology (NIBB), Okazaki, Aichi, 444-8787, Japan
| | - Chia-Hao Lin
- Division of Molecular Neurobiology, National Institute for Basic Biology (NIBB), Okazaki, Aichi, 444-8787, Japan
| | - Keiichi Hara
- Department of Pediatrics, National Hospital Organization Kure Medical Center, Kure, Hiroshima, 737-0023, Japan
| | - Reiko Kagawa
- Department of Pediatrics, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Hiroshima, 734-8551, Japan
| | - Satoshi Okada
- Department of Pediatrics, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Hiroshima, 734-8551, Japan
| | - Masao Kobayashi
- Department of Pediatrics, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Hiroshima, 734-8551, Japan
| | - Mayumi Ishikawa
- Department of Pediatrics, Kawasaki Municipal Hospital, Kawasaki, Kanagawa, 210-0013, Japan
| | - Makoto Anzo
- Department of Pediatrics, Kawasaki Municipal Hospital, Kawasaki, Kanagawa, 210-0013, Japan
| | - Hideo Cho
- Department of Pediatrics, Kawasaki Municipal Hospital, Kawasaki, Kanagawa, 210-0013, Japan
| | - Shinobu Takayasu
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, 036-8562, Japan
| | - Takeshi Nigawara
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, 036-8562, Japan
| | - Makoto Daimon
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, 036-8562, Japan
| | - Tomohiko Sato
- Department of Pediatrics, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, 036-8562, Japan
| | - Kiminori Terui
- Department of Pediatrics, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, 036-8562, Japan
| | - Etsuro Ito
- Department of Pediatrics, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, 036-8562, Japan
| | - Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology (NIBB), Okazaki, Aichi, 444-8787, Japan.,School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, 444-8787, Japan
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40
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Sakuta H, Nishihara E, Hiyama TY, Lin CH, Noda M. Nax signaling evoked by an increase in [Na+] in CSF induces water intake via EET-mediated TRPV4 activation. Am J Physiol Regul Integr Comp Physiol 2016; 311:R299-306. [DOI: 10.1152/ajpregu.00352.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 05/27/2016] [Indexed: 11/22/2022]
Abstract
Water-intake behavior is under the control of brain systems that sense body fluid conditions at sensory circumventricular organs (sCVOs); however, the underlying mechanisms have not yet been elucidated in detail. Nax is a sodium (Na+) level sensor in the brain, and the transient receptor potential vanilloid (TRPV) channels TRPV1 and TRPV4 have been proposed to function as osmosensors. We herein investigated voluntary water intake immediately induced after an intracerebroventricular administration of a hypertonic NaCl solution in TRPV1-, TRPV4-, Na x-, and their double-gene knockout (KO) mice. The induction of water intake by TRPV1-KO mice was normal, whereas intake by TRPV4-KO and Na x-KO mice was significantly less than that by WT mice. Water intake by Na x /TRPV4-double KO mice was similar to that by the respective single KO mice. When TRPV4 activity was blocked with a specific antagonist HC-067047, water intake by WT mice was significantly reduced, whereas intake by TRPV4-KO and Na x-KO mice was not. Similar results were obtained with the administration of miconazole, which inhibits the biosynthesis of epoxyeicosatrienoic acids (EETs), endogenous agonists for TRPV4, from arachidonic acid (AA). Intracerebroventricular injection of hypertonic NaCl with AA or 5,6-EET restored water intake by Na x-KO mice to the wild-type level but not that by TRPV4-KO mice. These results suggest that the Na+ signal generated in Nax-positive glial cells leads to the activation of TRPV4-positive neurons in sCVOs to stimulate water intake by using EETs as gliotransmitters. Intracerebroventricular injection of equiosmolar hypertonic sorbitol solution induced small but significant water intake equally in all the genotypes, suggesting the presence of an unknown osmosensor in the brain.
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Affiliation(s)
- Hiraki Sakuta
- Division of Molecular Neurobiology, National Institute for Basic Biology, and
- School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi, Japan
| | - Eri Nishihara
- Division of Molecular Neurobiology, National Institute for Basic Biology, and
| | - Takeshi Y. Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, and
- School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi, Japan
| | - Chia-Hao Lin
- Division of Molecular Neurobiology, National Institute for Basic Biology, and
| | - Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, and
- School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi, Japan
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41
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Role of cerebrospinal fluid-contacting nucleus in sodium sensing and sodium appetite. Physiol Behav 2015; 147:291-9. [DOI: 10.1016/j.physbeh.2015.04.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 11/23/2022]
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42
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de Souza Mecawi A, Ruginsk SG, Elias LLK, Varanda WA, Antunes‐Rodrigues J. Neuroendocrine Regulation of Hydromineral Homeostasis. Compr Physiol 2015; 5:1465-516. [DOI: 10.1002/cphy.c140031] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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43
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Matsumoto M, Hiyama TY, Kuboyama K, Suzuki R, Fujikawa A, Noda M. Channel properties of Nax expressed in neurons. PLoS One 2015; 10:e0126109. [PMID: 25961826 PMCID: PMC4427406 DOI: 10.1371/journal.pone.0126109] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 03/19/2015] [Indexed: 12/19/2022] Open
Abstract
Nax is a sodium-concentration ([Na+])-sensitive Na channel with a gating threshold of ~150 mM for extracellular [Na+] ([Na+]o) in vitro. We previously reported that Nax was preferentially expressed in the glial cells of sensory circumventricular organs including the subfornical organ, and was involved in [Na+] sensing for the control of salt-intake behavior. Although Nax was also suggested to be expressed in the neurons of some brain regions including the amygdala and cerebral cortex, the channel properties of Nax have not yet been adequately characterized in neurons. We herein verified that Nax was expressed in neurons in the lateral amygdala of mice using an antibody that was newly generated against mouse Nax. To investigate the channel properties of Nax expressed in neurons, we established an inducible cell line of Nax using the mouse neuroblastoma cell line, Neuro-2a, which is endogenously devoid of the expression of Nax. Functional analyses of this cell line revealed that the [Na+]-sensitivity of Nax in neuronal cells was similar to that expressed in glial cells. The cation selectivity sequence of the Nax channel in cations was revealed to be Na+ ≈ Li+ > Rb+ > Cs+ for the first time. Furthermore, we demonstrated that Nax bound to postsynaptic density protein 95 (PSD95) through its PSD95/Disc-large/ZO-1 (PDZ)-binding motif at the C-terminus in neurons. The interaction between Nax and PSD95 may be involved in promoting the surface expression of Nax channels because the depletion of endogenous PSD95 resulted in a decrease in Nax at the plasma membrane. These results indicated, for the first time, that Nax functions as a [Na+]-sensitive Na channel in neurons as well as in glial cells.
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Affiliation(s)
- Masahito Matsumoto
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Japan
| | - Takeshi Y. Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Japan
- School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Japan
| | - Kazuya Kuboyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Japan
| | - Ryoko Suzuki
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Japan
| | - Akihiro Fujikawa
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Japan
| | - Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Japan
- School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Japan
- * E-mail:
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44
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Thirst driving and suppressing signals encoded by distinct neural populations in the brain. Nature 2015; 520:349-52. [PMID: 25624099 PMCID: PMC4401619 DOI: 10.1038/nature14108] [Citation(s) in RCA: 160] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 11/24/2014] [Indexed: 12/18/2022]
Abstract
Thirst is the basic instinct to drink water. Previously, it was shown that neurons in several circumventricular organs (CVO) of the hypothalamus are activated by thirst-inducing conditions 1. Here, we identify two distinct, genetically-separable neural populations in the subfornical organ (SFO) that trigger or suppress thirst. We show that optogenetic activation of SFO excitatory neurons, marked by the expression of the transcription factor ETV-1, evokes intense drinking behavior, and does so even in fully water-satiated animals. The light-induced response is highly specific for water, immediate, and strictly locked to the laser stimulus. In contrast, activation of a second population of SFO neurons, marked by expression of the vesicular GABA transporter VGAT, drastically suppressed drinking, even in water-craving thirsty animals. These results reveal an innate brain circuit that can turn on and off an animal’s water-drinking behavior, and likely functions as a center for thirst control in the mammalian brain.
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45
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Lucio-Oliveira F, Traslaviña G, Borges B, Franci C. Modulation of the activity of vasopressinergic neurons by estrogen in rats refed with normal or sodium-free food after fasting. Neuroscience 2015; 284:325-336. [DOI: 10.1016/j.neuroscience.2014.09.076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 09/26/2014] [Accepted: 09/30/2014] [Indexed: 11/25/2022]
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46
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Nakano Y, Furube E, Morita S, Wanaka A, Nakashima T, Miyata S. Astrocytic TLR4 expression and LPS-induced nuclear translocation of STAT3 in the sensory circumventricular organs of adult mouse brain. J Neuroimmunol 2015; 278:144-58. [DOI: 10.1016/j.jneuroim.2014.12.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 12/13/2014] [Accepted: 12/13/2014] [Indexed: 12/26/2022]
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Hua B, Gao Y, Kong X, Yang L, Hou W, Bao Y. New insights of nociceptor sensitization in bone cancer pain. Expert Opin Ther Targets 2014; 19:227-43. [PMID: 25547644 DOI: 10.1517/14728222.2014.980815] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Numerous studies have shown that an intact CNS is required for the conscious perception of cancer-induced bone pain (CIBP) and that changes in the CNS are clearly evident. Accordingly, the blockage of nociceptive stimulus into the CNS can effectively relieve or markedly attenuate CIBP, revealing the clinical implication of the blockage of ongoing peripheral inputs for the control of CIBP. AREAS COVERED In this review, the heterogeneity and excitability of nociceptors in bone are covered. Furthermore, their role in initiating and maintaining CIBP is also described. EXPERT OPINION Developing mechanistic therapies to treat CIBP is a challenge, but they have the potential to fundamentally change our ability to effectively block/relieve CIBP and increase the functional status and quality of life of patients with bone metastasis. Further studies are desperately needed at both the preclinical and clinical levels to determine whether the targets as mentioned in this review are viable and feasible for patient populations.
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Affiliation(s)
- Baojin Hua
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Department of Oncology , Beixiange 5, Xicheng District, Beijing 100053 , China +86 10 88001221 ; +86 10 88001340 ;
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48
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Noda M, Hiyama TY. Sodium sensing in the brain. Pflugers Arch 2014; 467:465-74. [PMID: 25491503 PMCID: PMC4325189 DOI: 10.1007/s00424-014-1662-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/25/2014] [Accepted: 11/27/2014] [Indexed: 12/16/2022]
Abstract
Sodium (Na) homeostasis is crucial for life, and the Na+ level ([Na+]) of body fluids is strictly maintained at a range of 135–145 mM. However, the existence of a [Na+] sensor in the brain has long been controversial until Nax was identified as the molecular entity of the sensor. This review provides an overview of the [Na+]-sensing mechanism in the brain for the regulation of salt intake by summarizing a series of our studies on Nax. Nax is a Na channel expressed in the circumventricular organs (CVOs) in the brain. Among the CVOs, the subfornical organ (SFO) is the principal site for the control of salt intake behavior, where Nax populates the cellular processes of astrocytes and ependymal cells enveloping neurons. A local expression of endothelin-3 in the SFO modulates the [Na+] sensitivity for Nax activation, and thereby Nax is likely to be activated in the physiological [Na+] range. Nax stably interacts with Na+/K+-ATPase whereby Na+ influx via Nax is coupled with activation of Na+/K+-ATPase associated with the consumption of ATP. The consequent activation of anaerobic glucose metabolism of Nax-positive glial cells upregulates the cellular release of lactate, and this lactate functions as a gliotransmitter to activate GABAergic neurons in the SFO. The GABAergic neurons presumably regulate hypothetic neurons involved in the control of salt intake behavior. Recently, a patient with essential hypernatremia caused by autoimmunity to Nax was found. In this case, the hypernatremia was considered to be induced by the complement-mediated cell death in the CVOs, where Nax specifically populates.
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Affiliation(s)
- Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji-cho, Okazaki, 444-8787, Japan,
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49
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Orlov SN, Hamet P. Salt and gene expression: evidence for [Na+]i/[K+]i-mediated signaling pathways. Pflugers Arch 2014; 467:489-98. [PMID: 25479826 DOI: 10.1007/s00424-014-1650-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 10/27/2014] [Accepted: 11/07/2014] [Indexed: 01/11/2023]
Abstract
Our review focuses on the recent data showing that gene transcription and translation are under the control of signaling pathways triggered by modulation of the intracellular sodium/potassium ratio ([Na+]i/[K+]i). Side-by-side with sensing of osmolality elevation by tonicity enhancer-binding protein (TonEBP, NFAT5), [Na+]i/[K+]i-mediated excitation-transcription coupling may contribute to the transcriptomic changes evoked by high salt consumption. This novel mechanism includes the sensing of heightened Na+ concentration in the plasma, interstitial, and cerebrospinal fluids via augmented Na+ influx in the endothelium, immune system cells, and the subfornical organ, respectively. In these cells, [Na+]i/[K+]i ratio elevation, triggered by augmented Na+ influx, is further potentiated by increased production of endogenous Na+,K+-ATPase inhibitors documented in salt-sensitive hypertension.
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Affiliation(s)
- Sergei N Orlov
- Laboratory of Biological Membranes, Faculty of Biology, M.V. Lomonosov Moscow State University, Leninskie Gory 1/12, Moscow, 119991, Russia,
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50
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Berret E, Smith PY, Henry M, Soulet D, Hébert SS, Toth K, Mouginot D, Drolet G. Extracellular Na(+) levels regulate formation and activity of the NaX/alpha1-Na(+)/K(+)-ATPase complex in neuronal cells. Front Cell Neurosci 2014; 8:413. [PMID: 25538563 PMCID: PMC4255601 DOI: 10.3389/fncel.2014.00413] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 11/13/2014] [Indexed: 11/23/2022] Open
Abstract
MnPO neurons play a critical role in hydromineral homeostasis regulation by acting as sensors of extracellular sodium concentration ([Na+]out). The mechanism underlying Na+-sensing involves Na+-flow through the NaX channel, directly regulated by the Na+/K+-ATPase α1-isoform which controls Na+-influx by modulating channel permeability. Together, these two partners form a complex involved in the regulation of intracellular sodium ([Na+]in). Here we aim to determine whether environmental changes in Na+ could actively modulate the NaX/Na+/K+-ATPase complex activity. We investigated the complex activity using patch-clamp recordings from rat MnPO neurons and Neuro2a cells. When the rats were fed with a high-salt-diet, or the [Na+] in the culture medium was increased, the activity of the complex was up-regulated. In contrast, drop in environmental [Na+] decreased the activity of the complex. Interestingly under hypernatremic condition, the colocalization rate and protein level of both partners were up-regulated. Under hyponatremic condition, only NaX protein expression was increased and the level of NaX/Na+/K+-ATPase remained unaltered. This unbalance between NaX and Na+/K+-ATPase pump proportion would induce a bigger portion of Na+/K+-ATPase-control-free NaX channel. Thus, we suggest that hypernatremic environment increases NaX/Na+/K+-ATPase α1-isoform activity by increasing the number of both partners and their colocalization rate, whereas hyponatremic environment down-regulates complex activity via a decrease in the relative number of NaX channels controlled by the pump.
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Affiliation(s)
| | - Pascal Y Smith
- Centre de Recherche du CHU de Québec, Axe Neurosciences QC, Canada
| | - Mélaine Henry
- Centre de Recherche du CHU de Québec, Axe Neurosciences QC, Canada
| | - Denis Soulet
- Centre de Recherche du CHU de Québec, Axe Neurosciences QC, Canada ; Faculté de Médecine, Département de Psychiatrie et Neurosciences, Université Laval QC, Canada
| | - Sébastien S Hébert
- Centre de Recherche du CHU de Québec, Axe Neurosciences QC, Canada ; Faculté de Médecine, Département de Psychiatrie et Neurosciences, Université Laval QC, Canada
| | - Katalin Toth
- Faculté de Médecine, Département de Psychiatrie et Neurosciences, Université Laval QC, Canada ; Institut Universitaire de Santé Mentale de Québec, Université Laval QC, Canada
| | - Didier Mouginot
- Centre de Recherche du CHU de Québec, Axe Neurosciences QC, Canada ; Institut Universitaire de Santé Mentale de Québec, Université Laval QC, Canada
| | - Guy Drolet
- Centre de Recherche du CHU de Québec, Axe Neurosciences QC, Canada ; Faculté de Médecine, Département de Psychiatrie et Neurosciences, Université Laval QC, Canada
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