1
|
Wyart C, Carbo-Tano M, Cantaut-Belarif Y, Orts-Del'Immagine A, Böhm UL. Cerebrospinal fluid-contacting neurons: multimodal cells with diverse roles in the CNS. Nat Rev Neurosci 2023; 24:540-556. [PMID: 37558908 DOI: 10.1038/s41583-023-00723-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2023] [Indexed: 08/11/2023]
Abstract
The cerebrospinal fluid (CSF) is a complex solution that circulates around the CNS, and whose composition changes as a function of an animal's physiological state. Ciliated neurons that are bathed in the CSF - and thus referred to as CSF-contacting neurons (CSF-cNs) - are unusual polymodal interoceptive neurons. As chemoreceptors, CSF-cNs respond to variations in pH and osmolarity and to bacterial metabolites in the CSF. Their activation during infections of the CNS results in secretion of compounds to enhance host survival. As mechanosensory neurons, CSF-cNs operate together with an extracellular proteinaceous polymer known as the Reissner fibre to detect compression during spinal curvature. Once activated, CSF-cNs inhibit motor neurons, premotor excitatory neurons and command neurons to enhance movement speed and stabilize posture. At longer timescales, CSF-cNs instruct morphogenesis throughout life via the release of neuropeptides that act over long distances on skeletal muscle. Finally, recent evidence suggests that mouse CSF-cNs may act as neural stem cells in the spinal cord, inspiring new paths of investigation for repair after injury.
Collapse
Affiliation(s)
- Claire Wyart
- Institut du Cerveau (ICM), INSERM U1127, UMR CNRS 7225 Paris, Sorbonne Université, Paris, France.
| | - Martin Carbo-Tano
- Institut du Cerveau (ICM), INSERM U1127, UMR CNRS 7225 Paris, Sorbonne Université, Paris, France
| | - Yasmine Cantaut-Belarif
- Institut du Cerveau (ICM), INSERM U1127, UMR CNRS 7225 Paris, Sorbonne Université, Paris, France
| | | | - Urs L Böhm
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
2
|
Liu X, Rich K, Nasseri SM, Li G, Hjæresen S, Finsen B, Scherberger H, Svenningsen Å, Zhang M. A Comparison of PKD2L1-Expressing Cerebrospinal Fluid Contacting Neurons in Spinal Cords of Rodents, Carnivores, and Primates. Int J Mol Sci 2023; 24:13582. [PMID: 37686387 PMCID: PMC10488076 DOI: 10.3390/ijms241713582] [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: 08/16/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/10/2023] Open
Abstract
Cerebrospinal fluid contacting neurons (CSF-cNs) are a specific type of neurons located around the ventricles in the brain and the central canal in the spinal cord and have been demonstrated to be intrinsic sensory neurons in the central nervous system. One of the important channels responsible for the sensory function is the polycystic kidney disease 2-like 1 (PKD2L1) channel. Most of the studies concerning the distribution and function of the PKD2L1-expressing CSF-cNs in the spinal cord have previously been performed in non-mammalian vertebrates. In the present study immunohistochemistry was performed to determine the distribution of PKD2L1-immunoreactive (IR) CSF-cNs in the spinal cords of four mammalian species: mouse, rat, cat, and macaque monkey. Here, we found that PKD2L1-expressing CSF-cNs were present at all levels of the spinal cord in these animal species. Although the distribution pattern was similar across these species, differences existed. Mice and rats presented a clear PKD2L1-IR cell body labeling, whereas in cats and macaques the PKD2L1-IR cell bodies were more weakly labeled. Ectopic PKD2L1-IR neurons away from the ependymal layer were observed in all the animal species although the abundance and the detailed locations varied. The apical dendritic protrusions with ciliated fibers were clearly seen in the lumen of the central canal in all the animal species, but the sizes of protrusion bulbs were different among the species. PKD2L1-IR cell bodies/dendrites were co-expressed with doublecortin, MAP2 (microtubule-associated protein 2), and aromatic L-amino acid decarboxylase, but not with NeuN (neuronal nuclear protein), indicating their immature properties and ability to synthesize monoamine transmitters. In addition, in situ hybridization performed in rats revealed PKD2L1 mRNA expression in the cells around the central canal. Our results indicate that the intrinsic sensory neurons are conserved across non-mammalian and mammalian vertebrates. The similar morphology of the dendritic bulbs with ciliated fibers (probably representing stereocilia and kinocilia) protruding into the central canal across different animal species supports the notion that PKD2L1 is a chemo- and mechanical sensory channel that responds to mechanical stimulations and maintains homeostasis of the spinal cord. However, the differences of PKD2L1 distribution and expression between the species suggest that PKD2L1-expressing neurons may receive and process sensory signals differently in different animal species.
Collapse
Affiliation(s)
- Xiaohe Liu
- Department of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark; (X.L.); (K.R.); (S.M.N.); (G.L.); (S.H.); (B.F.); (Å.S.)
| | - Karen Rich
- Department of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark; (X.L.); (K.R.); (S.M.N.); (G.L.); (S.H.); (B.F.); (Å.S.)
| | - Sohail M. Nasseri
- Department of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark; (X.L.); (K.R.); (S.M.N.); (G.L.); (S.H.); (B.F.); (Å.S.)
| | - Guifa Li
- Department of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark; (X.L.); (K.R.); (S.M.N.); (G.L.); (S.H.); (B.F.); (Å.S.)
| | - Simone Hjæresen
- Department of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark; (X.L.); (K.R.); (S.M.N.); (G.L.); (S.H.); (B.F.); (Å.S.)
| | - Bente Finsen
- Department of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark; (X.L.); (K.R.); (S.M.N.); (G.L.); (S.H.); (B.F.); (Å.S.)
| | - Hansjörg Scherberger
- Deutsches Primantenzentrum, GmbH, 37077 Göttingen, Germany;
- Department of Biology and Psychology, University of Göttingen, 37077 Göttingen, Germany
| | - Åsa Svenningsen
- Department of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark; (X.L.); (K.R.); (S.M.N.); (G.L.); (S.H.); (B.F.); (Å.S.)
- BRIDGE, University of Southern Denmark, DK-5000 Odense, Denmark
| | - Mengliang Zhang
- Department of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark; (X.L.); (K.R.); (S.M.N.); (G.L.); (S.H.); (B.F.); (Å.S.)
- BRIDGE, University of Southern Denmark, DK-5000 Odense, Denmark
| |
Collapse
|
3
|
New LE, Yanagawa Y, McConkey GA, Deuchars J, Deuchars SA. GABAergic regulation of cell proliferation within the adult mouse spinal cord. Neuropharmacology 2023; 223:109326. [PMID: 36336067 DOI: 10.1016/j.neuropharm.2022.109326] [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: 04/14/2022] [Revised: 10/17/2022] [Accepted: 10/31/2022] [Indexed: 11/05/2022]
Abstract
Manipulation of neural stem cell proliferation and differentiation in the postnatal CNS is receiving significant attention due to therapeutic potential. In the spinal cord, such manipulations may promote repair in conditions such as multiple sclerosis or spinal cord injury, but may also limit excessive cell proliferation contributing to tumours such as ependymomas. We show that when ambient γ-aminobutyric acid (GABA) is increased in vigabatrin-treated or decreased by GAD67 allele haplodeficiency in glutamic acid decarboxylase67-green fluorescent protein (GAD67-GFP) mice of either sex, the numbers of proliferating cells respectively decreased or increased. Thus, intrinsic spinal cord GABA levels are correlated with the extent of cell proliferation, providing important evidence for manipulating these levels. Diazepam binding inhibitor, an endogenous protein that interacts with GABA receptors and its breakdown product, octadecaneuropeptide, which preferentially activates central benzodiazepine (CBR) sites, were highly expressed in spinal cord, especially in ependymal cells surrounding the central canal. Furthermore, animals with reduced CBR activation via treatment with flumazenil or Ro15-4513, or with a G2F77I mutation in the CBR binding site had greater numbers of Ethynyl-2'-deoxyuridine positive cells compared to control, which maintained their stem cell status since the proportion of newly proliferated cells becoming oligodendrocytes or astrocytes was significantly lower. Altering endogenous GABA levels or modulating GABAergic signalling through specific sites on GABA receptors therefore influences NSC proliferation in the adult spinal cord. These findings provide a basis for further study into how GABAergic signalling could be manipulated to enable spinal cord self-regeneration and recovery or limit pathological proliferative activity.
Collapse
Affiliation(s)
- Lauryn E New
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, UK
| | - Yuchio Yanagawa
- Department of Genetic and Behavioural Neuroscience, Gunma University, Graduate School of Medicine, Maebashi, 371-8511, Japan
| | - Glenn A McConkey
- School of Biology, Faculty of Biological Sciences, University of Leeds, UK
| | - Jim Deuchars
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, UK
| | - Susan A Deuchars
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, UK.
| |
Collapse
|
4
|
Alvarez MR, Alarcon JM, Roman CA, Lazaro D, Bobrowski-Khoury N, Baena-Caldas GP, Esber GR. Can a basic solution activate the inflammatory reflex? A review of potential mechanisms, opportunities, and challenges. Pharmacol Res 2023; 187:106525. [PMID: 36441036 DOI: 10.1016/j.phrs.2022.106525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/09/2022] [Accepted: 10/25/2022] [Indexed: 11/24/2022]
Abstract
Stimulation of the inflammatory reflex (IR) is a promising strategy to treat systemic inflammatory disorders. However, this strategy is hindered by the cost and side effects of traditional IR activators. Recently, oral intake of sodium bicarbonate (NaHCO3) has been suggested to activate the IR, providing a safe and inexpensive alternative. Critically, the mechanisms whereby NaHCO3 might achieve this effect and more broadly the pathways underlying the IR remain poorly understood. Here, we argue that the recognition of NaHCO3 as a potential IR activator presents exciting clinical and research opportunities. To aid this quest, we provide an integrative review of our current knowledge of the neural and cellular pathways mediating the IR and discuss the status of physiological models of IR activation. From this vantage point, we derive testable hypotheses on potential mechanisms whereby NaHCO3 might stimulate the IR and compare NaHCO3 with classic IR activators. Elucidation of these mechanisms will help determine the therapeutic value of NaHCO3 as an IR activator and provide new insights into the IR circuitry.
Collapse
Affiliation(s)
- Milena Rodriguez Alvarez
- Department of Internal Medicine, Division of Rheumatology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA.
| | - Juan Marcos Alarcon
- Department of Pathology, The Robert F. Furchgott Center for Neural and Behavioral Science, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
| | - Christopher A Roman
- Department of Cell Biology, State University of New York (SUNY) Downstate Health Sciences University, Brooklyn, NY 11203, USA
| | - Deana Lazaro
- Division of Rheumatology, Department of Internal Medicine, Veterans Affairs New York Harbor Healthcare System, Brooklyn, NY, USA
| | | | | | | |
Collapse
|
5
|
Nakamura Y, Kurabe M, Matsumoto M, Sato T, Miytashita S, Hoshina K, Kamiya Y, Tainaka K, Matsuzawa H, Ohno N, Ueno M. Cerebrospinal fluid-contacting neuron tracing reveals structural and functional connectivity for locomotion in the mouse spinal cord. eLife 2023; 12:83108. [PMID: 36805807 PMCID: PMC9943067 DOI: 10.7554/elife.83108] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 02/03/2023] [Indexed: 02/22/2023] Open
Abstract
Cerebrospinal fluid-contacting neurons (CSF-cNs) are enigmatic mechano- or chemosensory cells lying along the central canal of the spinal cord. Recent studies in zebrafish larvae and lampreys have shown that CSF-cNs control postures and movements via spinal connections. However, the structures, connectivity, and functions in mammals remain largely unknown. Here we developed a method to genetically target mouse CSF-cNs that highlighted structural connections and functions. We first found that intracerebroventricular injection of adeno-associated virus with a neuron-specific promoter and Pkd2l1-Cre mice specifically labeled CSF-cNs. Single-cell labeling of 71 CSF-cNs revealed rostral axon extensions of over 1800 μm in unmyelinated bundles in the ventral funiculus and terminated on CSF-cNs to form a recurrent circuitry, which was further determined by serial electron microscopy and electrophysiology. CSF-cNs were also found to connect with axial motor neurons and premotor interneurons around the central canal and within the axon bundles. Chemogenetic CSF-cNs inactivation reduced speed and step frequency during treadmill locomotion. Our data revealed the basic structures and connections of mouse CSF-cNs to control spinal motor circuits for proper locomotion. The versatile methods developed in this study will contribute to further understanding of CSF-cN functions in mammals.
Collapse
Affiliation(s)
- Yuka Nakamura
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata UniversityNiigataJapan
| | - Miyuki Kurabe
- Division of Anesthesiology, Niigata University Graduate School of Medical and Dental SciencesNiigataJapan
| | - Mami Matsumoto
- Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological SciencesOkazakiJapan,Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical SciencesNagoyaJapan
| | - Tokiharu Sato
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata UniversityNiigataJapan
| | - Satoshi Miytashita
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata UniversityNiigataJapan
| | - Kana Hoshina
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata UniversityNiigataJapan
| | - Yoshinori Kamiya
- Division of Anesthesiology, Niigata University Graduate School of Medical and Dental SciencesNiigataJapan
| | - Kazuki Tainaka
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata UniversityNiigataJapan
| | - Hitoshi Matsuzawa
- Center for Advanced Medicine and Clinical Research, Kashiwaba Neurosurgical HospitalSapporoJapan,Center for Integrated Human Brain Science, Niigata UniversityNiigataJapan
| | - Nobuhiko Ohno
- Department of Anatomy, Division of Histology and Cell Biology, Jichi Medical University, School of MedicineShimotsukeJapan,Division of Ultrastructural Research, National Institute for Physiological SciencesOkazakiJapan
| | - Masaki Ueno
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata UniversityNiigataJapan
| |
Collapse
|
6
|
Johnson E, Clark M, Oncul M, Pantiru A, MacLean C, Deuchars J, Deuchars SA, Johnston J. Graded spikes differentially signal neurotransmitter input in cerebrospinal fluid contacting neurons of the mouse spinal cord. iScience 2022; 26:105914. [PMID: 36691620 PMCID: PMC9860393 DOI: 10.1016/j.isci.2022.105914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 12/06/2022] [Accepted: 12/27/2022] [Indexed: 12/31/2022] Open
Abstract
The action potential and its all-or-none nature is fundamental to neural communication. Canonically, the action potential is initiated once voltage-activated Na+ channels are activated, and their rapid kinetics of activation and inactivation give rise to the action potential's all-or-none nature. Here we demonstrate that cerebrospinal fluid contacting neurons (CSFcNs) surrounding the central canal of the mouse spinal cord employ a different strategy. Rather than using voltage-activated Na+ channels to generate binary spikes, CSFcNs use two different types of voltage-activated Ca2+ channel, enabling spikes of different amplitude. T-type Ca2+ channels generate small amplitude spikes, whereas larger amplitude spikes require high voltage-activated Cd2+-sensitive Ca2+ channels. We demonstrate that these different amplitude spikes can signal input from different transmitter systems; purinergic inputs evoke smaller T-type dependent spikes whereas cholinergic inputs evoke larger spikes that do not rely on T-type channels. Different synaptic inputs to CSFcNs can therefore be signaled by the spike amplitude.
Collapse
Affiliation(s)
- Emily Johnson
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Marilyn Clark
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Merve Oncul
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Andreea Pantiru
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Claudia MacLean
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Jim Deuchars
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Susan A. Deuchars
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Jamie Johnston
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK,Corresponding author
| |
Collapse
|