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De Francesco PN, Fernandez G, Uriarte M, Urrutia L, Ponce de León M, Fehrentz JA, Falasco G, Perello M. Systemic Ghrelin Treatment Induces Rapid, Transient, and Asymmetric Changes in the Metabolic Activity of the Mouse Brain. Neuroendocrinology 2023; 113:64-79. [PMID: 35908540 DOI: 10.1159/000526245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 07/15/2022] [Indexed: 01/14/2023]
Abstract
INTRODUCTION Ghrelin regulates a variety of functions by acting in the brain. The targets of ghrelin in the mouse brain have been mainly mapped using immunolabeling against c-Fos, a transcription factor used as a marker of cellular activation, but such analysis has several limitations. Here, we used positron emission tomography in mice to investigate the brain areas responsive to ghrelin. METHODS We analyzed in male mice the brain areas responsive to systemically injected ghrelin using positron emission tomography imaging of 18F-fluoro-2-deoxyglucose (18F-FDG) uptake, an indicator of metabolic rate. Additionally, we studied if systemic administration of fluorescent ghrelin or native ghrelin displays symmetric accessibility or induction of c-Fos, respectively, in the brain of male mice. RESULTS Ghrelin increased 18F-FDG uptake in few specific areas of the isocortex, striatum, pallidum, thalamus, and midbrain at 0-10-min posttreatment. At the 10-20 and 20-30 min posttreatment, ghrelin induced mixed changes in 18F-FDG uptake in specific areas of the isocortex, striatum, pallidum, thalamus, and midbrain, as well as in areas of the olfactory areas, hippocampal and retrohippocampal regions, hypothalamus, pons, medulla, and even the cerebellum. Ghrelin-induced changes in 18F-FDG uptake were transient and asymmetric. Systemically administrated fluorescent-ghrelin-labeled midline brain areas known to contain fenestrated capillaries and the hypothalamic arcuate nucleus, where a symmetric labeling was observed. Ghrelin treatment also induced a symmetric increased c-Fos labeling in the arcuate nucleus. DISCUSSION/CONCLUSION Systemically injected ghrelin transiently and asymmetrically affects the metabolic activity of the brain of male mice in a wide range of areas, in a food intake-independent manner. The neurobiological bases of such asymmetry seem to be independent of the accessibility of ghrelin into the brain.
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Affiliation(s)
- Pablo Nicolás De Francesco
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata, La Plata, Argentina
| | - Gimena Fernandez
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata, La Plata, Argentina
| | - Maia Uriarte
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata, La Plata, Argentina
| | - Leandro Urrutia
- Center of Molecular Imaging of Neurological Research Institute (FLENI), Escobar, Argentina
| | | | - Jean-Alain Fehrentz
- Institut des Biomolécules Max Mousseron-UMR5247, Pôle Chimie Balard Recherche, Montpellier, France
| | - German Falasco
- Center of Molecular Imaging of Neurological Research Institute (FLENI), Escobar, Argentina
| | - Mario Perello
- Laboratory of Neurophysiology of the Multidisciplinary Institute of Cell Biology IMBICE, Argentine Research Council (CONICET) and Scientific Research Commission, Province of Buenos Aires (CIC-PBA), National University of La Plata, La Plata, Argentina
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, University of Uppsala, Uppsala, Sweden
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Abstract
The SARS-CoV-2 virus gains entry to cells by binding to angiotensin-converting enzyme 2 (ACE2). Since circumventricular organs and parts of the hypothalamus lack a blood-brain barrier, and immunohistochemical studies demonstrate that ACE2 is highly expressed in circumventricular organs which are intimately connected to the hypothalamus, and the hypothalamus itself, these might be easy entry points for SARS-CoV-2 into the brain via the circulation. High ACE2 protein expression is found in the subfornical organ, area postrema, and the paraventricular nucleus of the hypothalamus (PVH). The subfornical organ and PVH are parts of a circuit to regulate osmolarity in the blood, through the secretion of anti-diuretic hormone into the posterior pituitary. The PVH is also the stress response centre in the brain. It controls not only pre-ganglionic sympathetic neurons, but is also a source of corticotropin-releasing hormone, that induces the secretion of adrenocorticotropic hormone from the anterior pituitary. It is proposed that the function of ACE2 in the circumventricular organs and the PVH could be diminished by binding with SARS-CoV-2, thus leading to a reduction in the ACE2/Ang (1-7)/Mas receptor (MasR) signalling axis, that modulates ACE/Ang II/AT1R signalling. This could result in increased presympathetic activity/neuroendocrine secretion from the PVH, and effects on the hypothalamic-pituitary-adrenal axis activity. Besides the bloodstream, the hypothalamus might also be affected by SARS-CoV-2 via transneuronal spread along the olfactory/limbic pathways. Exploring potential therapeutic pathways to prevent or attenuate neurological symptoms of COVID-19, including drugs which modulate ACE signalling, remains an important area of unmet medical need.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology Research Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore.
| | - R L Satish
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Deron R Herr
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Heiss CN, Gravert E, Hultén M, Olofsson LE. MyD88 Deficiency, but Not Gut Microbiota Depletion, Is Sufficient to Modulate the Blood-Brain Barrier Function in the Mediobasal Hypothalamus. Mol Neurobiol 2022. [PMID: 35381888 DOI: 10.1007/s12035-022-02802-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 03/16/2022] [Indexed: 11/03/2022]
Abstract
Circumventricular organs (CVOs), including the mediobasal hypothalamus (MBH), have an incomplete blood–brain barrier (BBB). In this study, we determined if the BBB function in the MBH is modulated by the gut microbiota or by the Toll-like receptor (TLR) adapter proteins TRIF or MyD88 signaling. By injecting mice with Evans blue, a marker for BBB permeability, we show that germ-free (GF) and conventionally raised (CONV-R) mice did not differ in the number of Evans blue-positive cells in MBH. Acute modulation of the gut microbiota did not change the number of Evans blue-positive cells. In contrast, CONV-R Myd88−/− and Trif−/− mice had a reduced number of cells in direct contact to the circulation compared to wildtype (WT) mice. This was accompanied by increased tight junction proteins in the blood vessels in Myd88−/− mice. To further characterize the BBB function, we injected WT and Myd88 −/− CONV-R mice as well as WT GF mice with monosodium glutamate (MSG), a neurotoxin that does not cross the BBB. While MSG caused vast cell death in the MBH in CONV-R and GF WT mice, Myd88 −/− mice were protected from such cell death suggesting that fewer cells are exposed to the neurotoxin in the Myd88 −/− mice. Taken together, our results suggest that MyD88 deficiency, but not gut microbiota depletion, is sufficient to modulate the BBB function in the MBH.
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Nogueira AB, Hoshino HSR, Ortega NC, Dos Santos BGS, Teixeira MJ. Adult human neurogenesis: early studies clarify recent controversies and go further. Metab Brain Dis 2022; 37:153-172. [PMID: 34739659 DOI: 10.1007/s11011-021-00864-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/28/2021] [Indexed: 01/19/2023]
Abstract
Evidence on adult mammalian neurogenesis and scarce studies with human brains led to the idea that adult human neurogenesis occurs in the subgranular zone (SGZ) of the dentate gyrus and in the subventricular zone (SVZ). However, findings published from 2018 rekindled controversies on adult human SGZ neurogenesis. We systematically reviewed studies published during the first decade of characterization of adult human neurogenesis (1994-2004) - when the two-neurogenic-niche concept in humans was consolidated - and compared with further studies. The synthesis of both periods is that adult human neurogenesis occurs in an intensity ranging from practically zero to a level comparable to adult mammalian neurogenesis in general, which is the prevailing conclusion. Nonetheless, Bernier and colleagues showed in 2000 intriguing indications of adult human neurogenesis in a broad area including the limbic system. Likewise, we later showed evidence that limbic and hypothalamic structures surrounding the circumventricular organs form a continuous zone expressing neurogenesis markers encompassing the SGZ and SVZ. The conclusion is that publications from 2018 on adult human neurogenesis did not bring novel findings on location of neurogenic niches. Rather, we expect that the search of neurogenesis beyond the canonical adult mammalian neurogenic niches will confirm our indications that adult human neurogenesis is orchestrated in a broad brain area. We predict that this approach may, for example, clarify that human hippocampal neurogenesis occurs mostly in the CA1-subiculum zone and that the previously identified human rostral migratory stream arising from the SVZ is indeed the column of the fornix expressing neurogenesis markers.
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Affiliation(s)
- Adriano Barreto Nogueira
- Division of Neurosurgery (LIM 62), Hospital das Clínicas, Faculty of Medicine, University of São Paulo, São Paulo, Brazil.
- Neurosurgery Service, Hospital Regional do Vale do Paraíba, Taubaté, Brazil.
| | | | | | | | - Manoel Jacobsen Teixeira
- Division of Neurosurgery (LIM 62), Hospital das Clínicas, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
- Department of Neurology, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
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Matsushita T, Otani K, Oto Y, Takahashi Y, Kurosaka D, Kato F. Sustained microglial activation in the area postrema of collagen-induced arthritis mice. Arthritis Res Ther 2021; 23:273. [PMID: 34715926 DOI: 10.1186/s13075-021-02657-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 10/12/2021] [Indexed: 02/07/2023] Open
Abstract
Background Central nervous system (CNS)-mediated symptoms, such as fatigue, depression, and hyperalgesia, are common complications among patients with rheumatoid arthritis (RA). However, it remains unclear how the peripheral pathology of RA spreads to the brain. Accumulated evidence showing an association between serum cytokine levels and aberrant CNS function suggests that humoral factors participate in this mechanism. In contrast to the well-known early responses of microglia (CNS-resident immune cells) in the area postrema [AP; a brain region lacking a blood–brain barrier (BBB)] to experimental inflammation, microglial alterations in the AP during chronic inflammation like RA remain unclear. Therefore, to determine whether microglia in the AP can react to persistent autoimmune-arthritis conditions, we analyzed these cells in a mouse model of collagen-induced arthritis (CIA). Methods Microglial number and morphology were analyzed in the AP of CIA and control mice (administered Freund’s adjuvant or saline). Immunostaining for ionized calcium-binding adaptor molecule-1 was performed at various disease phases: “pre-onset” [post-immunization day (PID) 21], “establishment” (PID 35), and “chronic” (PID 56 and 84). Quantitative analyses of microglial number and morphology were performed, with principal component analysis used to classify microglia. Interleukin-1β (IL-1β) mRNA expression was analyzed by multiple fluorescent in situ hybridization and real-time polymerase chain reaction. Behavioral changes were assessed by sucrose preference test. Results Microglia in the AP significantly increased in density and exhibited changes in morphology during the establishment and chronic phases, but not the pre-onset phase. Non-subjective clustering classification of cell morphology (CIA, 1,256 cells; saline, 852 cells) showed that the proportion of highly activated microglia increased in the CIA group during establishment and chronic phases. Moreover, the density of IL-1β-positive microglia, a hallmark of functional activation, was increased in the AP. Sucrose preferences in CIA mice negatively correlated with IL-1β expression in brain regions containing the AP. Conclusions Our findings demonstrate that microglia in the AP can sustain their activated state during persistent autoimmune arthritis, which suggests that chronic inflammation, such as RA, may affect microglia in brain regions lacking a BBB and have various neural consequences. Supplementary Information The online version contains supplementary material available at 10.1186/s13075-021-02657-x.
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Abstract
Neuromyelitis optica (NMO) is an autoimmune disorder of the central nervous system that preferentially affects the optic nerve and the spinal cord. In around 80% of NMO patients, autoantibodies binding to aquaporin-4 (AQP4) are detected. AQP4-IgG unifies a spectrum of disorders (NMOSD) that include not only optic neuritis, longitudinally extensive transverse myelitis but also syndromes caused by lesion of the diencephalic region and the circumventricular organs (CVOs). The distinctive immunopathological characteristics of NMOSD lesions, occurring in regions where AQP4 is highly expressed, supports a central role for AQP4-IgG in disease pathogenesis. AQP4 expression is concentrated in CVOs and in the hypothalamus, mainly in the dorsal hypothalamic area, dorsomedial hypothalamic nucleus and suprachiasmatic nucleus. Several neuroendocrine disorders caused by inflammatory lesions involving the diencephalic region have been described in patients with NMOSD, including syndrome of inappropriate antidiuresis, sleep disorders, and other endocrinopathies caused by hypothalamic injury. Focus of this chapter is the involvement of hypothalamus and CVOs in AQP4 autoimmunity.
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Affiliation(s)
- Raffaele Iorio
- Neurology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, and Università Cattolica del Sacro Cuore, Rome, Italy
| | - Claudia Papi
- Neurology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, and Università Cattolica del Sacro Cuore, Rome, Italy
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Verheggen ICM, de Jong JJA, van Boxtel MPJ, Postma AA, Verhey FRJ, Jansen JFA, Backes WH. Permeability of the windows of the brain: feasibility of dynamic contrast-enhanced MRI of the circumventricular organs. Fluids Barriers CNS 2020; 17:66. [PMID: 33115484 PMCID: PMC7594295 DOI: 10.1186/s12987-020-00228-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 10/17/2020] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Circumventricular organs (CVOs) are small structures without a blood-brain barrier surrounding the brain ventricles that serve homeostasic functions and facilitate communication between the blood, cerebrospinal fluid and brain. Secretory CVOs release peptides and sensory CVOs regulate signal transmission. However, pathogens may enter the brain through the CVOs and trigger neuroinflammation and neurodegeneration. We investigated the feasibility of dynamic contrast-enhanced (DCE) MRI to assess the CVO permeability characteristics in vivo, and expected significant contrast uptake in these regions, due to blood-brain barrier absence. METHODS Twenty healthy, middle-aged to older males underwent brain DCE MRI. Pharmacokinetic modeling was applied to contrast concentration time-courses of CVOs, and in reference to white and gray matter. We investigated whether a significant and positive transfer from blood to brain could be measured in the CVOs, and whether this differed between secretory and sensory CVOs or from normal-appearing brain matter. RESULTS In both the secretory and sensory CVOs, the transfer constants were significantly positive, and all secretory CVOs had significantly higher transfer than each sensory CVO. The transfer constants in both the secretory and sensory CVOs were higher than in the white and gray matter. CONCLUSIONS Current measurements confirm the often-held assumption of highly permeable CVOs, of which the secretory types have the strongest blood-to-brain transfer. The current study suggests that DCE MRI could be a promising technique to further assess the function of the CVOs and how pathogens can potentially enter the brain via these structures. TRIAL REGISTRATION Netherlands Trial Register number: NL6358, date of registration: 2017-03-24.
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Affiliation(s)
- Inge C M Verheggen
- Department of Psychiatry and Neuropsychology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
- School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands.
- Alzheimer Center Limburg, Maastricht, The Netherlands.
| | - Joost J A de Jong
- School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Martin P J van Boxtel
- Department of Psychiatry and Neuropsychology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
- School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
- Alzheimer Center Limburg, Maastricht, The Netherlands
| | - Alida A Postma
- School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Frans R J Verhey
- Department of Psychiatry and Neuropsychology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
- School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
- Alzheimer Center Limburg, Maastricht, The Netherlands
| | - Jacobus F A Jansen
- School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Walter H Backes
- School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
- School for Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
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Litvin DG, Denstaedt SJ, Borkowski LF, Nichols NL, Dick TE, Smith CB, Jacono FJ. Peripheral-to-central immune communication at the area postrema glial-barrier following bleomycin-induced sterile lung injury in adult rats. Brain Behav Immun 2020; 87:610-633. [PMID: 32097765 PMCID: PMC8895345 DOI: 10.1016/j.bbi.2020.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 02/02/2020] [Accepted: 02/13/2020] [Indexed: 02/07/2023] Open
Abstract
The pathways for peripheral-to-central immune communication (P → C I-comm) following sterile lung injury (SLI) are unknown. SLI evokes systemic and central inflammation, which alters central respiratory control and viscerosensory transmission in the nucleus tractus solitarii (nTS). These functional changes coincide with increased interleukin-1 beta (IL-1β) in the area postrema, a sensory circumventricular organ that connects P → C I-comm to brainstem circuits that control homeostasis. We hypothesize that IL-1β and its downstream transcriptional target, cyclooxygenase-2 (COX-2), mediate P → C I-comm in the nTS. In a rodent model of SLI induced by intratracheal bleomycin (Bleo), the sigh frequency and duration of post-sigh apnea increased in Bleo- compared to saline- treated rats one week after injury. This SLI-dependent change in respiratory control occurred concurrently with augmented IL-1β and COX-2 immunoreactivity (IR) in the funiculus separans (FS), a barrier between the AP and the brainstem. At this barrier, increases in IL-1β and COX-2 IR were confined to processes that stained for glial fibrillary acidic protein (GFAP) and that projected basolaterally to the nTS. Further, FS radial-glia did not express TNF-α or IL-6 following SLI. To test our hypothesis, we blocked central COX-1/2 activity by intracerebroventricular (ICV) infusion of Indomethacin (Ind). Continuous ICV Ind treatment prevented Bleo-dependent increases in GFAP + and IL-1β + IR, and restored characteristics of sighs that reset the rhythm. These data indicate that changes in sighs following SLI depend partially on activation of a central COX-dependent P → C I-comm via radial-glia of the FS.
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Affiliation(s)
- David G Litvin
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Department of Fundamental Neuroscience, University of Lausanne, 1005 Lausanne, Switzerland
| | - Scott J Denstaedt
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109, United States
| | - Lauren F Borkowski
- Department of Biomedical Sciences, University of Missouri College of Veterinary Medicine, Columbia, MO 65212, United States
| | - Nicole L Nichols
- Department of Biomedical Sciences, University of Missouri College of Veterinary Medicine, Columbia, MO 65212, United States
| | - Thomas E Dick
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Corey B Smith
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Frank J Jacono
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, OH 44106, United States.
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El Hiba O, Draoui A, Gamrani H. The neuroactive neurosteroid Dehydroepiandrosterone Sulfate (DHEAS) modulates the serotonergic system within the dorsal Raphe nucleus and the cerebrospinal fluid release of Reissner's fiber in rat. C R Biol 2020; 343:101-110. [PMID: 32720492 DOI: 10.5802/crbiol.3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/08/2019] [Accepted: 12/09/2019] [Indexed: 11/24/2022]
Abstract
Dehydroepiandrosterone sulfate (DHEAS) exerts important functions in the nervous system, such as modulation of neuronal death, brain development, cognition and behavior. However, little is known about the possible interactions of this steroid with the glial cells, in particular those forming circumventricular organs (CVOs). The present study, on the one hand, was focused on the assessment of the possible effect of DHEAS on the subcommissural organ in rats. Known as one of the CVOs, the SCO can release a glycoprotein of high molecular weight named Reissner's fiber (RF) into the cerebrospinal fluid (CSF), a remarkable secretory activity. On the other hand, we examined the serotonergic innervation in the Dorsal Raphe nucleus (DRN) and the subsequent SCO. Our finding has revealed a significant increase in RF immunoreactivity within the SCO following a single i.p injection of DHEAS at a dose of 5 mg/kg B.W. A loss of serotonin (5-HT) within the DRN and fibers reaching the SCO was also observed. The present findings have brought evidence of a possible modulator potential of neurosteroids, in particular DHEAS, upon the secretory activity of the SCO. This study will open a new window for a better understanding of the main role and interaction of neurosteroids with one of the relevant circumventricular organs in the mammalian brain.
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Affiliation(s)
- Omar El Hiba
- Neuroscience, Pharmacology and Environment Unit, Faculty of Sciences Semlalia, Cadi Ayyad University, Avenue My Abdellah, B.P. 2390, Marrakesh, Morocco.,Nutrition and Food Sciences Team, Faculty of Sciences, Chouaib Doukkali University El Jadida, Route Ben Maachou, B.P. 20, Avenue des Facultés, El Jadida, Morocco.,Nutritional Physiopathologies Team, Faculty of Sciences, Chouaib Doukkali University El Jadida, Route Ben Maachou, B.P. 20, Avenue des Facultés, El Jadida, Morocco
| | - Ahmed Draoui
- Neuroscience, Pharmacology and Environment Unit, Faculty of Sciences Semlalia, Cadi Ayyad University, Avenue My Abdellah, B.P. 2390, Marrakesh, Morocco
| | - Halima Gamrani
- Neuroscience, Pharmacology and Environment Unit, Faculty of Sciences Semlalia, Cadi Ayyad University, Avenue My Abdellah, B.P. 2390, Marrakesh, Morocco
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Asami A, Kurganov E, Miyata S. Proliferation of endothelial cells in the choroid plexus of normal and hydrocephalic mice. J Chem Neuroanat 2020; 106:101796. [PMID: 32360474 DOI: 10.1016/j.jchemneu.2020.101796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 04/16/2020] [Accepted: 04/16/2020] [Indexed: 01/08/2023]
Abstract
The choroid plexus (CP), located at the walls of the brain ventricles, produces and secretes cerebrospinal fluid (CSF). Hydrocephalus is a neurological disorder in which the CP abnormally secretes excess amounts of CSF into the ventricles. There is currently no information on the vascular dynamics of the CP in adult brains under normal and hydrocephalic conditions. In the present study, we reported the continuous proliferation of endothelial cells in the CP of normal mice, which depended on vascular endothelial cell growth factor (VEGF). The proliferation of endothelial cells increased in mice with intraventricular hemorrhage, which was attenuated by a pretreatment with the toll-like receptor 4 (TLR4) inhibitor VIPER. Moreover, the intracerebroventricular infusion of the TLR4 agonist, lipopolysaccharide, increased endothelial cell proliferation in the CP and induced ventriculomegaly. The present results provide insights into the importance of the TLR4-initiated and VEGF-dependent proliferation of endothelial cells in the pathogenesis of hydrocephalus.
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Affiliation(s)
- Ayumi Asami
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Erkin Kurganov
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Seiji Miyata
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan.
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Abstract
The blood-brain barrier (BBB) protects the vertebrate central nervous system from harmful blood-borne, endogenous and exogenous substances to ensure proper neuronal function. The BBB describes a function that is established by endothelial cells of CNS vessels in conjunction with pericytes, astrocytes, neurons and microglia, together forming the neurovascular unit (NVU). Endothelial barrier function is crucially induced and maintained by the Wnt/β-catenin pathway and requires intact NVU for proper functionality. The BBB and the NVU are characterized by a specialized assortment of molecular specializations, providing the basis for tightening, transport and immune response functionality.The present chapter introduces state-of-the-art knowledge of BBB structure and function and highlights current research topics, aiming to understanding in more depth the cellular and molecular interactions at the NVU, determining functionality of the BBB in health and disease, and providing novel potential targets for therapeutic BBB modulation. Moreover, we highlight recent advances in understanding BBB and NVU heterogeneity within the CNS as well as their contribution to CNS physiology, such as neurovascular coupling, and pathophysiology, is discussed. Finally, we give an outlook onto new avenues of BBB research.
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Affiliation(s)
- Fabienne Benz
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Stefan Liebner
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany.
- Excellence Cluster Cardio Pulmonary System (CPI), Partner Site Frankfurt, Frankfurt, Germany.
- German Center for Cardiovascular Research (DZHK), Partner Site Frankfurt/Mainz, Frankfurt, Germany.
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13
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Gordon L, Blechman J, Shimoni E, Gur D, Anand-Apte B, Levkowitz G. The fenestrae-associated protein Plvap regulates the rate of blood-borne protein passage into the hypophysis. Development 2019; 146:dev.177790. [PMID: 31740533 DOI: 10.1242/dev.177790] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 11/08/2019] [Indexed: 12/13/2022]
Abstract
To maintain body homeostasis, endocrine systems must detect and integrate blood-borne peripheral signals. This is mediated by fenestrae, specialized permeable pores in the endothelial membrane. Plasmalemma vesicle-associated protein (Plvap) is located in the fenestral diaphragm and is thought to play a role in the passage of proteins through the fenestrae. However, this suggested function has yet to be demonstrated directly. We studied the development of fenestrated capillaries in the hypophysis, a major neuroendocrine interface between the blood and brain. Using a transgenic biosensor to visualize the vascular excretion of the genetically tagged plasma protein DBP-EGFP, we show that the developmental acquisition of vascular permeability coincides with differential expression of zebrafish plvap orthologs in the hypophysis versus brain. Ultrastructural analysis revealed that plvapb mutants display deficiencies in fenestral diaphragms and increased density of hypophyseal fenestrae. Measurements of DBP-EGFP extravasation in plvapb mutants provided direct proof that Plvap limits the rate of blood-borne protein passage through fenestrated endothelia. We present the regulatory role of Plvap in the development of blood-borne protein detection machinery at a neuroendocrine interface through which hormones are released to the general circulation.
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Affiliation(s)
- Ludmila Gordon
- Department of Molecular Cell Biology, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Janna Blechman
- Department of Molecular Cell Biology, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Eyal Shimoni
- Chemical Research Support, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Dvir Gur
- Department of Molecular Cell Biology, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Bela Anand-Apte
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland OH 444195, USA
| | - Gil Levkowitz
- Department of Molecular Cell Biology, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
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14
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Staudt N, Giger FA, Fielding T, Hutt JA, Foucher I, Snowden V, Hellich A, Kiecker C, Houart C. Pineal progenitors originate from a non-neural territory limited by FGF signalling. Development 2019; 146:dev.171405. [PMID: 31754007 PMCID: PMC7375831 DOI: 10.1242/dev.171405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 10/30/2019] [Indexed: 01/10/2023]
Abstract
The embryonic development of the pineal organ, a neuroendocrine gland on top of the diencephalon, remains enigmatic. Classic fate-mapping studies suggested that pineal progenitors originate from the lateral border of the anterior neural plate. We show here, using gene expression and fate mapping/lineage tracing in zebrafish, that pineal progenitors originate, at least in part, from the non-neural ectoderm. Gene expression in chick indicates that this non-neural origin of pineal progenitors is conserved in amniotes. Genetic repression of placodal, but not neural crest, cell fate results in pineal hypoplasia in zebrafish, while mis-expression of transcription factors known to specify placodal identity during gastrulation promotes the formation of ectopic pineal progenitors. We also demonstrate that fibroblast growth factors (FGFs) position the pineal progenitor domain within the non-neural border by repressing pineal fate and that the Otx transcription factors promote pinealogenesis by inhibiting this FGF activity. The non-neural origin of the pineal organ reveals an underlying similarity in the formation of the pineal and pituitary glands, and suggests that all CNS neuroendocrine organs may require a non-neural contribution to form neurosecretory cells. Highlighted Article: Gene expression and fate mapping/lineage tracing in zebrafish reveals that the pineal organ develops from the non-neural pre-placodal ectoderm under the control of FGF signalling.
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Affiliation(s)
- Nicole Staudt
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
| | - Florence A Giger
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
| | - Triona Fielding
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
| | - James A Hutt
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
| | - Isabelle Foucher
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
| | - Vicky Snowden
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
| | - Agathe Hellich
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
| | - Clemens Kiecker
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
| | - Corinne Houart
- Department for Developmental Neurobiology, Guy's Hospital Campus, King's College London, London SE1 1UL, UK
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15
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Bonnan M, Mejdoubi M, Cabre P. Fulminant and fatal onset of pan-aquaporinopathy. Mult Scler Relat Disord 2019; 34:116-118. [PMID: 31255987 DOI: 10.1016/j.msard.2019.06.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 06/16/2019] [Accepted: 06/24/2019] [Indexed: 11/27/2022]
Abstract
Early administration of high-dose steroids and plasma exchange (PE) offers the best chance of treating neuromyelitis optica spectrum disease (NMOSD) attacks, but up to 20% of patients fail to respond. We report the case of a first devastating NMOSD attack leading to death despite optimal treatment. While receiving steroids during a bilateral blinding optic neuritis, this female patient suffered a severe attack involving the spinal cord and circumventricular organs (CVOs), including the pineal gland. Early adjunctive daily PE failed to prevent sudden death. AQP4-antibodies were strongly positive. To our knowledge, this is the first case of exceptionally severe monophasic NMOSD leading to full-blown lesions in all AQP4-expressing sites. Lesions of the periventricular ependyma and CVOs are highly exceptional and the involvement of the pineal gland, which is also a CVO, is novel. Moreover, the patient's condition continued to worsen until death, without any sign of recovery. We term this unexpected outcome the 'anti-Lazarus effect'. Although the mechanisms of resistance to treatment remain elusive, very early initiation of immunosuppressive drugs or adjunctive salvage therapies could be envisioned to manage these devastating attacks.
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Affiliation(s)
- Mickael Bonnan
- Service de Neurologie, Centre Hospitalier de Pau, 4 Bd Hauterive, 64000 Pau, France.
| | - Mehdi Mejdoubi
- Service de Radiologie, Hôpital Zobda Quitman, 97261 Fort-de-France, French West Indies
| | - Philippe Cabre
- Service de Neurologie, Hôpital Zobda Quitman, 97261 Fort-de-France, French West Indies
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16
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Buijs RM, Guzmán Ruiz MA, Méndez Hernández R, Rodríguez Cortés B. The suprachiasmatic nucleus; a responsive clock regulating homeostasis by daily changing the setpoints of physiological parameters. Auton Neurosci 2019; 218:43-50. [PMID: 30890347 DOI: 10.1016/j.autneu.2019.02.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/05/2019] [Accepted: 02/06/2019] [Indexed: 12/13/2022]
Abstract
The suprachiasmatic nucleus (SCN) is responsible for determining circadian variations in physiological setpoints. The SCN achieves such control through projections to different target structures within and outside the hypothalamus. Thus the SCN prepares the physiology of the body every 24 h via hormones and autonomic nervous system (ANS), to coming changes in behavior. Resulting rhythms in hormones and ANS activity transmit a precise message to selective organs, adapting their sensitivity to coming hormones, metabolites or other essentials. Thus the SCN as autonomous clock gives rhythm to physiological processes. However when the body is challenged by infections, low or high temperature, food shortage or excess: physiological setpoints need to be changed. For example, under fasting conditions, setpoints for body temperature and glucose levels are lowered at the beginning of the sleep (inactive) phase. However, starting the active phase, a normal increase in glucose and temperature levels take place to support activities associated with the acquisition of food. Thus, the SCN adjusts physiological setpoints in agreement with time of the day and according to challenges faced by the body. The SCN is enabled to do this by receiving extensive input from brain areas involved in sensing the condition of the body. Therefore, when the body receives stimuli contradicting normal physiology, such as eating or activity during the inactive period, this information reaches the SCN, adapting its output to correct this disbalance. As consequence frequent violations of the SCN message, such as by shift work or night eating, will result in development of disease.
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Affiliation(s)
- Ruud M Buijs
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, PC 04510 Mexico D.F., Mexico.
| | - Mara A Guzmán Ruiz
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, PC 04510 Mexico D.F., Mexico
| | - Rebeca Méndez Hernández
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, PC 04510 Mexico D.F., Mexico
| | - Betty Rodríguez Cortés
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, PC 04510 Mexico D.F., Mexico
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17
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Abstract
Increasing evidence suggests that hydrogen sulfide (H2S) is involved in brain mechanisms regulating the functions of the circulatory system. This appears to be mediated by cardiovascular centers located in the central nervous system. This chapter describes techniques of acute and chronic infusions into the brain cardiovascular centers in rats. Rats may be implanted either acutely or chronically with a cannula inserted into a selected cardiovascular center according to the stereotaxic coordinates. The cannula allows for the administration of the investigated compounds into a selected cardiovascular center.
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Affiliation(s)
- Marcin Ufnal
- Laboratory of Centre for Preclinical Research, Department of Experimental Physiology and Pathophysiology, Medical University of Warsaw, Warsaw, Poland.
| | - Artur Nowinski
- Laboratory of Centre for Preclinical Research, Department of Experimental Physiology and Pathophysiology, Medical University of Warsaw, Warsaw, Poland
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18
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Abstract
Localization and distribution of hypothalamic neurons expressing the nonapeptide oxytocin has been extensively studied. Their projections to the neurohypophyseal system release oxytocin into the systemic circulation thus controlling endocrine events associated with reproduction in males and females. Oxytocinergic neurons seem to be confined to the ventral hypothalamus in all mammals. Groups of such cells located outside the supraoptic and the paraventricular nuclei are summarized as "accessory neurons." Although evolutionary probably associated with the classical magocellular nuclei, accessory oxytocin neurons seem to consist of rather heterogenous groups: Periventricular oxytocin neurons may gain contact to the third ventricle to secrete the peptide into the cerebrospinal fluid. Perivascular neurons may be involved in control of cerebral blood flow. They may also gain access to the portal circulation of the anterior pituitary lobe. Central projections of oxytocinergic neurons extend to portions of the limbic system, to the mesencephalon and to the brain stem. Such projections have been associated with control of behaviors, central stress response as well as motor and vegetative functions. Activity of the different oxytocinergic systems seems to be malleable to functional status, strongly influenced by systemic levels of steroid hormones.
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19
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Abstract
Glucagon-like peptide-1 (GLP-1) is a peptide hormone and member of the incretin family. GLP-1 related drugs, such as liraglutide, are widely used to treat diabetic patients and work by stimulating pancreatic β cells to increase glucose-dependent insulin secretion. However, extrapancreatic effects, such as appetite suppression or emesis, are observed in response to GLP-1 receptor agonists. In this study we used the in vitro patch-clamp method in acute brainstem preparations of mice and demonstrated that GLP-1 acts directly on area postrema neurons. It is known that activation of the area postrema is related to the induction of homeostatic autonomic nervous systems, including nausea. Approximately,half of the neurons tested in the area postrema were excited by GLP-1 in the presence of tetrodotoxin, and is thought to be through adenylate cyclase-cAMP pathways. Excitation was not frequently observed in nucleus tractus solitaries neurons or in area postrema neurons from GLP-1 receptor knock-out mice. These results indicate that GLP-1 receptor agonists excite area postrema neurons and potentially leading to the expression of extra-pancreatic effects. This is the first study to show that GLP-1 directly activates area postrema neurons.
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Affiliation(s)
- Masahiro Kawatani
- Department of Neurophysiology, Akita University, School of Medicine, Akita, Japan.
| | - Yuichiro Yamada
- Department of Endocrinology, Diabetes and Geriatric Medicine, Akita University, School of Medicine, Akita, Japan
| | - Masahito Kawatani
- Department of Neurophysiology, Akita University, School of Medicine, Akita, Japan
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20
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Al-Kaabi M, Hussam F, Al-Marsoummi S, Al-Anbaki A, Al-Salihi A, Al-Aubaidy H. Expression of ZO1, vimentin, pan-cadherin and AGTR1 in tanycyte-like cells of the sulcus medianus organum. Biochem Biophys Res Commun 2018; 502:243-249. [PMID: 29803674 DOI: 10.1016/j.bbrc.2018.05.151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 05/22/2018] [Indexed: 11/19/2022]
Abstract
Tanycytes are a specialized ependymal lining of brain ventricles with exceptional features of having long basal processes and junctional complexes between cell bodies. These tanycytes are present at the regions of circumventricular organs (CVOs) which possess common morphological and functional features enabling them to be described as the brain windows where the barrier systems have special properties. Previous studies detailed seven of these CVOs but little information is available regarding another putative site at the rostral part of the median sulcus of the 4th ventricle, or the sulcus medianus organum (SMO). Here we performed a pilot immunohistochemical study to support earlier observations suggesting the SMO as a novel CVO. We labeled rat brain with ZO1, vimentin, pan-cadherin and angiotensin II type 1 receptors markers which showed a morphologically distinct population of cells at the region of the SMO similar to tanycytes present in the median eminence, a known CVO. These cells had basal processes reaching the deeply seated blood vessels while the caudal part of the median sulcus did not show similar long cellular extensions. We concluded that tanycyte-like cells are present in the SMO in a pattern resembling that of other CVOs where the strategic location of the SMO is probably for signal integration between brainstem nuclei and the rostrally located neuronal centers.
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Affiliation(s)
- Muthanna Al-Kaabi
- Al-Nahrain University, College of Medicine, Department of Human Anatomy, Baghdad, Iraq; University of Tasmania, Faculty of Health, School of Medicine, Medical Science Precinct, Hobart, Tasmania, Australia
| | - Fadhil Hussam
- Al-Nahrain University, College of Medicine, Department of Human Anatomy, Baghdad, Iraq
| | - Sarmad Al-Marsoummi
- Al-Nahrain University, College of Medicine, Department of Human Anatomy, Baghdad, Iraq; University of North Dakota, School of Medicine and Health Sciences, Department of Biomedical Sciences, North Dakota, USA
| | - Ali Al-Anbaki
- University of Manchester, Faculty of Biology, Medicine and Health, Manchester, UK
| | - Anam Al-Salihi
- Al-Nahrain University, College of Medicine, Department of Human Anatomy, Baghdad, Iraq
| | - Hayder Al-Aubaidy
- La Trobe University, School of Life Sciences, Department of Physiology, Anatomy & Microbiology, Bundoora, VIC, 3086, Australia.
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21
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Masocha W, Kristensson K. Human African trypanosomiasis: How do the parasites enter and cause dysfunctions of the nervous system in murine models? Brain Res Bull 2018; 145:18-29. [PMID: 29870779 DOI: 10.1016/j.brainresbull.2018.05.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/24/2018] [Accepted: 05/30/2018] [Indexed: 12/27/2022]
Abstract
In this review we describe how Trypanosoma brucei brucei, a rodent pathogenic strain of African trypanosomes, can invade the nervous system, first by localization to the choroid plexus, the circumventricular organs (CVOs) and peripheral ganglia, which have fenestrated vessels, followed by crossing of the blood-brain barrier (BBB) into the white matter, hypothalamus, thalamus and basal ganglia. White blood cells (WBCs) pave the way for the trypanosome neuroinvasion. Experiments with immune deficient mice show that the invasion of WBCs is initiated by the toll-like receptor 9, followed by an augmentation phase that depends on the cytokine IFN-γ and the chemokine CXCL10. Nitric oxide (NO) derived from iNOS then prevents a break-down of the BBB and non-regulated passage of cells. This chain of events is relevant for design of better diagnostic tools to distinguish the different stages of the disease as well as for better understanding of the pathogenesis of the nervous system dysfunctions, which include circadian rhythm changes with sleep pattern disruption, pain syndromes, movement disorders and mental disturbances including dementia.
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Affiliation(s)
- Willias Masocha
- Department of Pharmacology and Therapeutics, Faculty of Pharmacy, Kuwait University, Kuwait.
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22
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Azuma M, Hirai T, Kadota Y, Khant ZA, Hattori Y, Kitajima M, Uetani H, Yamashita Y. Circumventricular organs of human brain visualized on post-contrast 3D fluid-attenuated inversion recovery imaging. Neuroradiology 2018; 60:583-590. [PMID: 29721578 DOI: 10.1007/s00234-018-2023-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 04/10/2018] [Indexed: 02/06/2023]
Abstract
PURPOSE Although contrast-enhanced three-dimensional T2 fluid-attenuated inversion recovery (3D T2-FLAIR) images are useful for assessing various neuronal diseases, physiological enhancement of the circumventricular organs on the images have not been investigated. We aimed to assess the physiological appearance of the circumventricular organs on contrast-enhanced 3D T2-FLAIR images. METHODS We studied 3-T MR images of the brain of 30 individuals with no apparent brain abnormalities. In ten areas of the brain, the degree of contrast enhancement on 3D T2-FLAIR and magnetization-prepared rapid gradient-echo (MPRAGE) images was evaluated using a 4-point grading system. The pre- and post-contrast mean contrast ratios (CRs) of the anterior pituitary gland, median eminence, and pineal gland were compared. RESULTS On post-contrast 3D T2-FLAIR images, marked enhancement was most frequently scored in the median eminence, followed by the choroid plexus, posterior pituitary gland, and pineal gland. In 10 of the 30 cases, the vascular organ of the lamina terminalis and the area postrema were enhanced but the subcommissural organ was not. The difference in the mean pre- and post-contrast CRs of the median eminence and pineal gland was statistically significant, while that of the anterior pituitary gland was not. CONCLUSION On contrast-enhanced 3D T2-FLAIR images, the circumventricular organs show variable enhancement. Our findings help to recognize physiological and abnormal enhancement of brain structures on contrast-enhanced 3D T2-FLAIR images.
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Affiliation(s)
- Minako Azuma
- Department of Radiology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.
| | - Toshinori Hirai
- Department of Radiology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan
| | - Yoshihito Kadota
- Department of Radiology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan
| | - Zaw Aung Khant
- Department of Radiology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan
| | - Yohei Hattori
- Department of Radiology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan
| | - Mika Kitajima
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Hiroyuki Uetani
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Yasuyuki Yamashita
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
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23
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Dangarembizi R, Erlwanger KH, Rummel C, Roth J, Madziva MT, Harden LM. Brewer's yeast is a potent inducer of fever, sickness behavior and inflammation within the brain. Brain Behav Immun 2018; 68:211-223. [PMID: 29074357 DOI: 10.1016/j.bbi.2017.10.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/08/2017] [Accepted: 10/21/2017] [Indexed: 02/08/2023] Open
Abstract
Brewer's yeast, derived from the yeast species Saccharomyces cerevisiae (S. cerevisiae), is commonly used for inducing pyrexia in pharmacological studies screening antipyretics in rats. Despite its widespread use, the peripheral and central inflammatory response associated with Brewer's yeast-induced fever and sickness behavior in rats has not been investigated. Thus, we injected male Sprague-Dawley rats (150-200 g) subcutaneously with a high (4 g/kg, n = 9), medium (2 g/kg, n = 5) or low (0.4 g/kg, n = 6) dose of Brewer's yeast solution or saline (0.9%, n = 6) and measured core body temperature, cage activity, food intake and body mass for six days after injection. Blood and brain samples were collected at 2, 8, 18 and 72 h after injection; n = 5-7 per time point. Brewer's yeast administration dose-dependently induced fever, lethargy, anorexia and body mass stunting that was accompanied by increased blood plasma levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α and activation of inflammatory transcription factors (nuclear factor (NF) for interleukin-6, signal transducer and activator of transcription (STAT)-3, and NF-κB)) in the hypothalamus and circumventricular organs. The increased activation of transcription factors following Brewer's yeast administration was accompanied by increased hypothalamic mRNA expression of TNF-α, IL-1β and IL-6 and rate-limiting enzymes for prostaglandin synthesis. Our results show that subcutaneous administration of S. cerevisae induces prolonged fever, anorexia and lethargy that is accompanied by a pronounced increase in the synthesis of pro-inflammatory cytokines, key prostaglandin synthesizing enzymes and transcription factors, in the periphery and brain.
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Affiliation(s)
- R Dangarembizi
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193 Johannesburg, South Africa; Department of Physiology and Anatomy, Faculty of Medicine, National University of Science and Technology, Box AC939, Ascot, Bulawayo, Zimbabwe.
| | - K H Erlwanger
- School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193 Johannesburg, South Africa
| | - C Rummel
- Institute of Veterinary Physiology and Biochemistry, Justus-Liebig University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany
| | - J Roth
- Institute of Veterinary Physiology and Biochemistry, Justus-Liebig University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany
| | - M T Madziva
- School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193 Johannesburg, South Africa
| | - L M Harden
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193 Johannesburg, South Africa
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24
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Abstract
The brain ventricular system (BVS) consists of brain ventricles and channels connecting ventricles filled with cerebrospinal fluid (CSF). The disturbance of CSF flow has been linked to neurodegenerative disease including hydrocephalus, which manifests itself as an abnormal expansion of BVS. This relatively common developmental disorder has been observed in human and domesticated animals and linked to functional deficiency of various cells lineages facing BVS, including the choroid plexus or ependymal cells that generate CSF or the ciliated cells that cilia beating generates CSF flow. To understand the underlying causes of hydrocephalus, several animal models were developed, including rodents (mice, rat, and hamster) and zebrafish. At another side of a spectrum of BVS anomalies there is the “slit-ventricle” syndrome, which develops due to insufficient inflation of BVS. Recent advances in functional genetics of zebrafish brought to light novel genetic elements involved in development of BVS and circulation of CSF. This review aims to reveal common elements of morphologically different BVS of zebrafish as a typical representative of teleosts and other vertebrates and illustrate useful features of the zebrafish model for studies of BVS. Along this line, recent analyses of the two novel zebrafish mutants affecting different subunits of the potassium voltage-gated channels allowed to emphasize an important functional convergence of the evolutionarily conserved elements of protein transport essential for BVS development, which were revealed by the zebrafish and mouse studies.
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Affiliation(s)
- Vladimir Korzh
- International Institute of Molecular and Cell Biology, Warsaw, Poland.
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25
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Oliveira M, Fernández F, Solé J, Pumarola M. Morphological, histological and immunohistochemical study of the area postrema in the dog. Anat Sci Int 2017; 93:188-196. [PMID: 28063139 DOI: 10.1007/s12565-016-0388-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 12/10/2016] [Indexed: 02/05/2023]
Abstract
Circumventricular organs are specialized brain structures that are located mainly at the midsagittal line, around the third and fourth ventricles, often protruding into the lumen. They are positioned at the interface between the neuroparenchyma and the ventricular system of the brain. These highly vascularized nervous tissue structures differ from the brain parenchyma, as they lack a blood-brain barrier. Circumventricular organs have specialized sensory and secretory functions. It is essential for any pathologist who evaluates brain sections to have a solid knowledge of microscopic neuroanatomy and to recognize these numerous specialized structures within the nervous system as normal and not mistake them for pathological changes. The purpose of this study was to provide, for the first time, a detailed and complete histological description of the healthy canine area postrema and to determine its resemblance to that of other mammalian species. Anatomical dissections with routine histological and immunohistochemical techniques were carried out on ten canine brains. The cellular composition of area postrema proved to be largely comparable to that of other mammal species.
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Affiliation(s)
- Maria Oliveira
- Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain. .,Fundació Hospital Clínic Veterinari, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain. .,Pride Veterinary Centre, Derby, DE24 8HX, UK.
| | - Francisco Fernández
- Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Jordi Solé
- Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Martí Pumarola
- Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Liberini CG, Borner T, Boyle CN, Lutz TA. The satiating hormone amylin enhances neurogenesis in the area postrema of adult rats. Mol Metab 2016; 5:834-843. [PMID: 27688997 PMCID: PMC5034493 DOI: 10.1016/j.molmet.2016.06.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 06/22/2016] [Accepted: 06/27/2016] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVE Adult neurogenesis in the subgranular zone and subventricular zone is generally accepted, but its existence in other brain areas is still controversial. Circumventricular organs, such as the area postrema (AP) have recently been described as potential neurogenic niches in the adult brain. The AP is the major site of action of the satiating hormone amylin. Amylin has been shown to promote the formation of neuronal projections originating from the AP in neonatal rodents but the role of amylin in adult neurogenesis remains unknown. METHODS To test this, we first performed an RNA-sequencing of the AP of adult rats acutely injected with either amylin (20 μg/kg), amylin plus the amylin receptor antagonist AC187 (500 μg/kg) or vehicle. Second, animals were subcutaneously equipped with minipumps releasing either amylin (50 μg/kg/day) or vehicle for 3 weeks to assess cell proliferation and differentiation with the 5'-bromo-2-deoxyuridine (BrdU) technique. RESULTS Acute amylin injections affected genes involved in pathways and processes that control adult neurogenesis. Amylin consistently upregulated NeuroD1 transcript and protein in the adult AP, and this effect was blocked by the co-administration of AC187. Further, chronic amylin treatment increased the number of newly proliferated AP-cells and significantly promoted their differentiation into neurons rather than astrocytes. CONCLUSION Our findings revealed a novel role of the satiating hormone amylin in promoting neurogenesis in the AP of adult rats.
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Key Words
- AP, area postrema
- Adult neurogenesis
- Amylin
- Area postrema
- BrdU
- BrdU, 5′-bromo-2-deoxyuridine
- CR, calretinin
- CTR, calcitonin receptor
- CVO, circumventricular organs
- Circumventricular organs
- ERK1/2, extracellular signal-regulated kinase 1 and 2
- EphRs, ephrin receptors
- FDR, false discovery rate
- GO, gene ontology
- ME, median eminence
- NGS, next generation sequencing
- NSC, neural stem cells
- NeuroD, neuronal differentiation
- NeuroD1, neuronal differentiation-1
- RAMP, receptor activity-modifying protein
- Wnt, Wingless-Type MMTV Integration Site Family
- bHLH, basic helix-loop-helix
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Affiliation(s)
- Claudia G Liberini
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich (UZH), 8057 Zurich, Switzerland; Zurich Centre for Integrative Human Physiology (ZIHP), University of Zurich, 8057 Zurich, Switzerland; Zurich Centre for Clinical Studies, Vetsuisse Faculty University of Zurich, 8057 Zurich, Switzerland
| | - Tito Borner
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich (UZH), 8057 Zurich, Switzerland; Zurich Centre for Integrative Human Physiology (ZIHP), University of Zurich, 8057 Zurich, Switzerland
| | - Christina N Boyle
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich (UZH), 8057 Zurich, Switzerland.
| | - Thomas A Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich (UZH), 8057 Zurich, Switzerland; Zurich Centre for Integrative Human Physiology (ZIHP), University of Zurich, 8057 Zurich, Switzerland
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Abstract
The mechanisms involved in cardiovascular regulation, such as vascular tone, fluid volume and blood osmolarity, are quite often mediated by signals circulating in the periphery, such as angiotensin II and sodium concentration. Research has identified areas within the lamina terminalis (LT), specifically the sensory circumventricular organs (CVOs), the subfornical organ and the organum vasculosum of the lamina terminalis, as playing crucial roles detecting and integrating information derived from these circulating signals. The median preoptic nucleus (MnPO) is a third integrative structure within the LT that influences cardiovascular homeostasis, although to date, its role is not as clearly elucidated. More recent studies have demonstrated that the CVOs are not only essential in the detection of traditional cardiovascular signals but also signals primarily considered to be important in the regulation of metabolic, reproductive and inflammatory processes that have now also been implicated in cardiovascular regulation. In this review, we highlight the critical roles played by the LT in the detection and integration of circulating signals that provide critical feedback control information contributing to cardiovascular regulation.
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Affiliation(s)
- Nicole M Cancelliere
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, K7L 3N6, Canada
| | - Emily A E Black
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, K7L 3N6, Canada
| | - Alastair V Ferguson
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, K7L 3N6, Canada.
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Chong W, Kim SN, Han SK, Lee SY, Ryu PD. Low Non-NMDA Receptor Current Density as Possible Protection Mechanism from Neurotoxicity of Circulating Glutamate on Subfornical Organ Neurons in Rats. Korean J Physiol Pharmacol 2015; 19:177-81. [PMID: 25729280 PMCID: PMC4342738 DOI: 10.4196/kjpp.2015.19.2.177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 01/08/2015] [Accepted: 01/09/2015] [Indexed: 11/17/2022]
Abstract
The subfornical organ (SFO) is one of circumventricular organs characterized by the lack of a normal blood brain barrier. The SFO neurons are exposed to circulating glutamate (60~100 µM), which may cause excitotoxicity in the central nervous system. However, it remains unclear how SFO neurons are protected from excitotoxicity caused by circulating glutamate. In this study, we compared the glutamate-induced whole cell currents in SFO neurons to those in hippocampal CA1 neurons using the patch clamp technique in brain slice. Glutamate (100 µM) induced an inward current in both SFO and hippocampal CA1 neurons. The density of glutamate-induced current in SFO neurons was significantly smaller than that in hippocampal CA1 neurons (0.55 vs. 2.07 pA/pF, p<0.05). To further identify the subtype of the glutamate receptors involved, the whole cell currents induced by selective agonists were then compared. The current densities induced by AMPA (0.45 pA/pF) and kainate (0.83 pA/pF), non-NMDA glutamate receptor agonists in SFO neurons were also smaller than those in hippocampal CA1 neurons (2.44 pA/pF for AMPA, p<0.05; 2.34 pA/pF for kainate, p< 0.05). However, the current density by NMDA in SFO neurons was not significantly different from that of hippocampal CA1 neurons (1.58 vs. 1.47 pA/pF, p>0.05). These results demonstrate that glutamate-mediated action through non-NMDA glutamate receptors in SFO neurons is smaller than that of hippocampal CA1 neurons, suggesting a possible protection mechanism from excitotoxicity by circulating glutamate in SFO neurons.
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Affiliation(s)
- Wonee Chong
- Department of Veterinary Pharmacology, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea
| | - Seong Nam Kim
- Department of Veterinary Pharmacology, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea
| | - Seong Kyu Han
- Department of Oral Physiology, School of Dentistry and Institute of Oral Bioscience, Chonbuk National University, Jeonju 561-756, Korea
| | - So Yeong Lee
- Department of Veterinary Pharmacology, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea
| | - Pan Dong Ryu
- Department of Veterinary Pharmacology, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea
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Pócsai K, Kálmán M. Immunohistochemical detectability of cerebrovascular utrophin depends on the condition of basal lamina. Neurosci Lett 2014; 583:182-7. [PMID: 25281792 DOI: 10.1016/j.neulet.2014.09.044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 09/21/2014] [Accepted: 09/23/2014] [Indexed: 10/24/2022]
Abstract
Utrophin is an autosomal homologue of dystrophin. Dystrophin is a member of the dystrophin-glycoprotein complex, which is a cell surface receptor for basal lamina components. In recent opinions utrophin occurs in the cerebrovascular endothelium but not in the perivascular glia. Cerebrovascular laminin immunoreactivity can only be detected in the subpial segments of the vessels, in circumventricular organs lacking blood-brain barrier, in immature vessels and following brain lesions. In our former experience utrophin immunoreactivity showed similar phenomena to that of laminin. The present study investigates the parallel occurrence of vascular utrophin and laminin immunoreactivity in the brain tissue, especially in the circumventricular organs, and during the parallel postnatal regression of both utrophin and laminin immunoreactivity. Their cerebrovascular immunoreactivity observed in frozen sections renders plausible the role of hidden but explorable epitopes, instead of a real absence of laminin and utrophin. The laminin epitopes are supposed to be hidden due to the fusion of the glial (i.e. brain parenchymal) and vascular basal laminae (Krum et al., Exp. Neurol. 111 (1991) 151). In all cases including its post-lesion re-appearance published formerly by us, laminin immunoreactivity may be attributed to the separation of glial and vascular basal laminae. Utrophin is localized, however, intracellularly, therefore a more complex molecular mechanism is to be assumed and it remains to be investigated how structural changes of the basal lamina may indirectly affect the immunoreactivity of utrophin. The results indicate that immunoreactivity may be influenced not only by the presence or absence of macromolecules but also by their functional state.
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Affiliation(s)
- Károly Pócsai
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary.
| | - Mihály Kálmán
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
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31
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Bernstein HG, Hölzl G, Dobrowolny H, Hildebrandt J, Trübner K, Krohn M, Bogerts B, Pahnke J. Vascular and extravascular distribution of the ATP-binding cassette transporters ABCB1 and ABCC1 in aged human brain and pituitary. Mech Ageing Dev 2014; 141-142:12-21. [PMID: 25218792 DOI: 10.1016/j.mad.2014.08.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 07/14/2014] [Accepted: 08/28/2014] [Indexed: 12/11/2022]
Abstract
ATP-binding cassette (ABC) transporters play an increasing role in the understanding of pathologic peptide deposition in neurodegenerative diseases (NDs), such as Alzheimer's and Parkinson's. To describe the location of the most important ABC transporters for NDs in human brain tissue, we investigated ABCB1 and ABCC1 immunohistologically in the adult human brain and pituitary. Both transporters have similar but not identical expression patterns. In brain regions with an established blood-brain barrier (BBB), ABCB1 and ABCC1 were ubiquitously expressed in endothelial cells of the microvasculature and in a subset of larger blood vessels (mostly venules). Remarkably, both transporters were also found in fenestrated capillaries in circumventricular organs where the BBB is absent. Moreover, ABCB1 and ABCC1 were also expressed in various non-endothelia cells such as pericytes, astrocytes, choroid plexus epithelia, ventricle ependymal cells, and neurons. With regard to their neuronal expression it was shown that both transporters are located in specific nerve cell populations, which are also immunopositive for three putative cell markers of purinergic cell signalling, namely 5'-nucleotidase, adenosine deaminase and nucleoside triphosphate diphosphohydrolase-2. Therefore, we speculate that neuronal expression of ABCB1 and ABCC1 might be linked to adenosinergic/purinergic neuromodulation. Lastly, both transporters were observed in multiple adenohypophyseal cells.
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Szathmari A, Jouvet A, Mottolese C, Champier J, Fèvre Montange M. Anatomical, molecular and pathological consideration of the circumventricular organs. Neurochirurgie 2015; 61:90-100. [PMID: 24974365 DOI: 10.1016/j.neuchi.2013.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 04/15/2013] [Accepted: 04/23/2013] [Indexed: 01/25/2023]
Abstract
BACKGROUND AND PURPOSE Circumventricular organs (CVOs) are a diverse group of specialised structures characterized by peculiar vascular and position around the third and fourth ventricles of the brain. In humans, these organs are present during the fetal period and some become vestigial after birth. Some, such as the pineal gland (PG), subcommissural organ (SCO) and organum vasculosum of the lamina terminalis (OVLT), which are located around the third ventricle, might be the site of origin of periventricular tumours. In contrast to humans, CVOs are present in the adult rat and can be dissected by laser capture microdissection (LCM). METHODS In this study, we used LCM and microarrays to analyse the transcriptomes of three CVOs, the SCO, the subfornical organ (SFO) and the PG and the third ventricle ependyma of the adult rat, in order to better characterise these organs at the molecular level. Furthermore, an immunohistochemical study of Claudin-3 (CLDN3), a membrane protein involved in forming cellular tight junctions, was performed at the level of the SCO. RESULTS This study highlighted some potentially new or already described specific markers of these structures as Erbb2 and Col11a1 in ependyma, Epcam and CLDN3 in the SCO, Ren1 and Slc22a3 in the SFO and Tph, Anat and Asmt in the PG. Moreover, we found that CLDN3 expression was restricted to the apical pole of ependymocytes in the SCO.
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33
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Ufnal M, Skrzypecki J. Blood borne hormones in a cross-talk between peripheral and brain mechanisms regulating blood pressure, the role of circumventricular organs. Neuropeptides 2014; 48:65-73. [PMID: 24485840 DOI: 10.1016/j.npep.2014.01.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 01/08/2014] [Accepted: 01/10/2014] [Indexed: 12/11/2022]
Abstract
Accumulating evidence suggests that blood borne hormones modulate brain mechanisms regulating blood pressure. This appears to be mediated by the circumventricular organs which are located in the walls of the brain ventricular system and lack the blood-brain barrier. Recent evidence shows that neurons of the circumventricular organs express receptors for the majority of cardiovascular hormones. Intracerebroventricular infusions of hormones and their antagonists is one approach to evaluate the influence of blood borne hormones on the neural mechanisms regulating arterial blood pressure. Interestingly, there is no clear correlation between peripheral and central effects of cardiovascular hormones. For example, angiotensin II increases blood pressure acting peripherally and centrally, whereas peripherally acting pressor catecholamines decrease blood pressure when infused intracerebroventricularly. The physiological role of such dual hemodynamic responses has not yet been clarified. In the paper we review studies on hemodynamic effects of catecholamines, neuropeptide Y, angiotensin II, aldosterone, natriuretic peptides, endothelins, histamine and bradykinin in the context of their role in a cross-talk between peripheral and brain mechanisms involved in the regulation of arterial blood pressure.
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Affiliation(s)
- Marcin Ufnal
- Department of Experimental and Clinical Physiology, Medical University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland.
| | - Janusz Skrzypecki
- Department of Experimental and Clinical Physiology, Medical University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland
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