1
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Zhao D, Hu M, Liu S. Glial cells in the mammalian olfactory bulb. Front Cell Neurosci 2024; 18:1426094. [PMID: 39081666 PMCID: PMC11286597 DOI: 10.3389/fncel.2024.1426094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 06/24/2024] [Indexed: 08/02/2024] Open
Abstract
The mammalian olfactory bulb (OB), an essential part of the olfactory system, plays a critical role in odor detection and neural processing. Historically, research has predominantly focused on the neuronal components of the OB, often overlooking the vital contributions of glial cells. Recent advancements, however, underscore the significant roles that glial cells play within this intricate neural structure. This review discus the diverse functions and dynamics of glial cells in the mammalian OB, mainly focused on astrocytes, microglia, oligodendrocytes, olfactory ensheathing cells, and radial glia cells. Each type of glial contributes uniquely to the OB's functionality, influencing everything from synaptic modulation and neuronal survival to immune defense and axonal guidance. The review features their roles in maintaining neural health, their involvement in neurodegenerative diseases, and their potential in therapeutic applications for neuroregeneration. By providing a comprehensive overview of glial cell types, their mechanisms, and interactions within the OB, this article aims to enhance our understanding of the olfactory system's complexity and the pivotal roles glial cells play in both health and disease.
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Affiliation(s)
| | | | - Shaolin Liu
- Isakson Center for Neurological Disease Research, Department of Physiology and Pharmacology, Department of Biomedical Sciences, University of Georgia College of Veterinary Medicine, Athens, GA, United States
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2
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Kharlamova AS, Godovalova OS, Otlyga EG, Proshchina AE. Primary and secondary olfactory centres in human ontogeny. Neurosci Res 2023; 190:1-16. [PMID: 36521642 DOI: 10.1016/j.neures.2022.12.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/19/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022]
Abstract
The olfactory centres are the evolutionary oldest and most conservative area of the telencephalon. Olfactory deficiencies are involved in a large spectrum of neurologic disorders and neurodegenerative diseases. The growing interest in human olfaction has been also been driven by COVID-19-induced transitional anosmia. Nevertheless, recent data on the human olfactory centres concerning normal histology and morphogenesis are rare. Published data in the field are mainly restricted to classic studies with non-uniform nomenclature and varied definitions of certain olfactory areas. While the olfactory system in model animals (rats, mice, and more rarely non-human primates) has been extensively investigated, the developmental timetable of olfactory centres in both human prenatal and postnatal ontogeny are poorly understood and unsystemised, which complicates the process of analysing human material, including medical researches. The main purpose of this review is to provide and discuss relevant morphological data on the normal ontogeny of the human olfactory centres, with a focus on the timetable of maturation and developmental cytoarchitecture, and with special reference to the definitions and terminology of certain olfactory areas.
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Affiliation(s)
- A S Kharlamova
- Avtsyn Research Institute of Human Morphology of FSBSI "Petrovsky National Research Centre of Surgery", Tsyurupy st., 3, 117418 Moscow, Russia.
| | - O S Godovalova
- Moscow Regional Research Institute of Obstetrics and Gynecology, Pokrovka St., 22A, 101000 Moscow, Russia
| | - E G Otlyga
- Avtsyn Research Institute of Human Morphology of FSBSI "Petrovsky National Research Centre of Surgery", Tsyurupy st., 3, 117418 Moscow, Russia
| | - A E Proshchina
- Avtsyn Research Institute of Human Morphology of FSBSI "Petrovsky National Research Centre of Surgery", Tsyurupy st., 3, 117418 Moscow, Russia
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3
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Cotellessa L, Marelli F, Duminuco P, Adamo M, Papadakis GE, Bartoloni L, Sato N, Lang-Muritano M, Troendle A, Dhillo WS, Morelli A, Guarnieri G, Pitteloud N, Persani L, Bonomi M, Giacobini P, Vezzoli V. Defective jagged-1 signaling affects GnRH development and contributes to congenital hypogonadotropic hypogonadism. JCI Insight 2023; 8:161998. [PMID: 36729644 PMCID: PMC10077483 DOI: 10.1172/jci.insight.161998] [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: 05/18/2022] [Accepted: 02/01/2023] [Indexed: 02/03/2023] Open
Abstract
In vertebrate species, fertility is controlled by gonadotropin-releasing hormone (GnRH) neurons. GnRH cells arise outside the central nervous system, in the developing olfactory pit, and migrate along olfactory/vomeronasal/terminal nerve axons into the forebrain during embryonic development. Congenital hypogonadotropic hypogonadism (CHH) and Kallmann syndrome are rare genetic disorders characterized by infertility, and they are associated with defects in GnRH neuron migration and/or altered GnRH secretion and signaling. Here, we documented the expression of the jagged-1/Notch signaling pathway in GnRH neurons and along the GnRH neuron migratory route both in zebrafish embryos and in human fetuses. Genetic knockdown of the zebrafish ortholog of JAG1 (jag1b) resulted in altered GnRH migration and olfactory axonal projections to the olfactory bulbs. Next-generation sequencing was performed in 467 CHH unrelated probands, leading to the identification of heterozygous rare variants in JAG1. Functional in vitro validation of JAG1 mutants revealed that 7 out of the 9 studied variants exhibited reduced protein levels and altered subcellular localization. Together our data provide compelling evidence that Jag1/Notch signaling plays a prominent role in the development of GnRH neurons, and we propose that JAG1 insufficiency may contribute to the pathogenesis of CHH in humans.
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Affiliation(s)
- Ludovica Cotellessa
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy.,University Lille, INSERM, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition UMR-S 1172, FHU 1000 days for health, Lille, France
| | - Federica Marelli
- Department of Endocrine and Metabolic Diseases, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Paolo Duminuco
- Department of Endocrine and Metabolic Diseases, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Michela Adamo
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Georgios E Papadakis
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Lucia Bartoloni
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Naoko Sato
- Department of Pediatrics, University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Mariarosaria Lang-Muritano
- Department of Pediatric Endocrinology and Diabetology, University Children's Hospital, Zurich, Switzerland
| | - Amineh Troendle
- Department of Endocrinology, Diabetology, and Metabolism, Lindenhofspital, Bern, Switzerland
| | - Waljit S Dhillo
- Division of Diabetes, Endocrinology and Metabolism, Imperial College London, London, United Kingdom
| | - Annamaria Morelli
- Department of Experimental and Clinical Medicine, University of Florence, Italy
| | - Giulia Guarnieri
- Department of Experimental and Clinical Medicine, University of Florence, Italy
| | - Nelly Pitteloud
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Luca Persani
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy.,Department of Endocrine and Metabolic Diseases, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Marco Bonomi
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy.,Department of Endocrine and Metabolic Diseases, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Paolo Giacobini
- University Lille, INSERM, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition UMR-S 1172, FHU 1000 days for health, Lille, France
| | - Valeria Vezzoli
- Department of Endocrine and Metabolic Diseases, IRCCS Istituto Auxologico Italiano, Milan, Italy
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4
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Duittoz AH, Tillet Y, Geller S. The great migration: how glial cells could regulate GnRH neuron development and shape adult reproductive life. J Chem Neuroanat 2022; 125:102149. [PMID: 36058434 DOI: 10.1016/j.jchemneu.2022.102149] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 10/31/2022]
Abstract
In mammals, reproductive function is under the control of hypothalamic neurons named Gonadotropin-Releasing Hormone (GnRH) neurons. These neurons migrate from the olfactory placode to the brain, during embryonic development. For the past 40 years, these neurons have been considered an example of tangential migration, i.e., dependent on the olfactory/vomeronasal/terminal nerves. Numerous studies have highlighted the factors involved in the migration of these neurons but thus far overlooked the cellular microenvironment that produces them. Many of these factors are dysregulated in hypogonadotropic hypogonadism, resulting in subfertility/infertility. Nevertheless, over the past ten years, several papers have reported the influence of glial cells (named olfactory ensheathing cells [OECs]) in the migration and differentiation of GnRH neurons. This review will describe the atypical origins, migration, and differentiation of these neurons, focusing on the latest discoveries. There will be a more specific discussion on the involvement of OECs in the development of GnRH neurons, during embryonic and perinatal life; as well as on their potential implication in the development of congenital or idiopathic hypogonadotropic hypogonadism (such as Kallmann syndrome).
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Affiliation(s)
- Anne H Duittoz
- Physiologie de la Reproduction et des Comportements (PRC) UMR7247 INRA, CNRS, Centre INRA Val de Loire, Université de Tours, IFCE, 37380 Nouzilly, France
| | - Yves Tillet
- Physiologie de la Reproduction et des Comportements (PRC) UMR7247 INRA, CNRS, Centre INRA Val de Loire, Université de Tours, IFCE, 37380 Nouzilly, France
| | - Sarah Geller
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland.
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5
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Dorrego-Rivas A, Grubb MS. Developing and maintaining a nose-to-brain map of odorant identity. Open Biol 2022; 12:220053. [PMID: 35765817 PMCID: PMC9240688 DOI: 10.1098/rsob.220053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Olfactory sensory neurons (OSNs) in the olfactory epithelium of the nose transduce chemical odorant stimuli into electrical signals. These signals are then sent to the OSNs' target structure in the brain, the main olfactory bulb (OB), which performs the initial stages of sensory processing in olfaction. The projection of OSNs to the OB is highly organized in a chemospatial map, whereby axon terminals from OSNs expressing the same odorant receptor (OR) coalesce into individual spherical structures known as glomeruli. This nose-to-brain map of odorant identity is built from late embryonic development to early postnatal life, through a complex combination of genetically encoded, OR-dependent and activity-dependent mechanisms. It must then be actively maintained throughout adulthood as OSNs experience turnover due to external insult and ongoing neurogenesis. Our review describes and discusses these two distinct and crucial processes in olfaction, focusing on the known mechanisms that first establish and then maintain chemospatial order in the mammalian OSN-to-OB projection.
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Affiliation(s)
- Ana Dorrego-Rivas
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Matthew S. Grubb
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
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6
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Tufo C, Poopalasundaram S, Dorrego-Rivas A, Ford MC, Graham A, Grubb MS. Development of the mammalian main olfactory bulb. Development 2022; 149:274348. [PMID: 35147186 PMCID: PMC8918810 DOI: 10.1242/dev.200210] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The mammalian main olfactory bulb is a crucial processing centre for the sense of smell. The olfactory bulb forms early during development and is functional from birth. However, the olfactory system continues to mature and change throughout life as a target of constitutive adult neurogenesis. Our Review synthesises current knowledge of prenatal, postnatal and adult olfactory bulb development, focusing on the maturation, morphology, functions and interactions of its diverse constituent glutamatergic and GABAergic cell types. We highlight not only the great advances in the understanding of olfactory bulb development made in recent years, but also the gaps in our present knowledge that most urgently require addressing. Summary: This Review describes the morphological and functional maturation of cells in the mammalian main olfactory bulb, from embryonic development to adult neurogenesis.
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Affiliation(s)
- Candida Tufo
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Subathra Poopalasundaram
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Ana Dorrego-Rivas
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Marc C Ford
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Anthony Graham
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Matthew S Grubb
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
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7
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Docampo-Seara A, Candal E, Rodríguez MA. Study of the glial cytoarchitecture of the developing olfactory bulb of a shark using immunochemical markers of radial glia. Brain Struct Funct 2022; 227:1067-1082. [PMID: 34997380 PMCID: PMC8930965 DOI: 10.1007/s00429-021-02448-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 12/22/2021] [Indexed: 11/30/2022]
Abstract
During development of the olfactory bulb (OB), glial cells play key roles in axonal guiding/targeting, glomerular formation and synaptic plasticity. Studies in mammals have shown that radial glial cells and peripheral olfactory glia (olfactory ensheathing cells, OECs) are involved in the development of the OB. Most studies about the OB glia were carried out in mammals, but data are lacking in most non-mammalian vertebrates. In the present work, we studied the development of the OB glial system in the cartilaginous fish Scyliorhinus canicula (catshark) using antibodies against glial markers, such as glial fibrillary acidic protein (GFAP), brain lipid-binding protein (BLBP), and glutamine synthase (GS). These glial markers were expressed in cells with radial morphology lining the OB ventricle of embryos and this expression continues in ependymal cells (tanycytes) in early juveniles. Astrocyte-like cells were also observed in the granular layer and surrounding glomeruli. Numerous GS-positive cells were present in the primary olfactory pathway of embryos. In the developmental stages analysed, the olfactory nerve layer and the glomerular layer were the regions with higher GFAP, BLBP and GS immuno-reactivity. In addition, numerous BLBP-expressing cells (a marker of mammalian OECs) showing proliferative activity were present in the olfactory nerve layer. Our findings suggest that glial cells of peripheral and central origin coexist in the OB of catshark embryos and early juveniles. These results open the path for future studies about the differential roles of glial cells in the catshark OB during embryonic development and in adulthood.
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Affiliation(s)
- A Docampo-Seara
- Departamento de Bioloxía Funcional, Centro de Investigación en Bioloxía (CIBUS), Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain.,UCL Institute of Ophthalmology, University College London, London, UK
| | - E Candal
- Departamento de Bioloxía Funcional, Centro de Investigación en Bioloxía (CIBUS), Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - M A Rodríguez
- Departamento de Bioloxía Funcional, Centro de Investigación en Bioloxía (CIBUS), Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain.
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8
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Takesono A, Kudoh T, Tyler CR. Application of Transgenic Zebrafish Models for Studying the Effects of Estrogenic Endocrine Disrupting Chemicals on Embryonic Brain Development. Front Pharmacol 2022; 13:718072. [PMID: 35264948 PMCID: PMC8900011 DOI: 10.3389/fphar.2022.718072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 01/14/2022] [Indexed: 11/13/2022] Open
Abstract
Endocrine disrupting chemicals (EDCs) are environmental pollutants that mimic hormones and/or disrupt their function. Estrogenic EDCs (eEDCs) interfere with endogenous estrogen signalling pathway(s) and laboratory animal and human epidemiological studies have provided evidence for a causal link between exposure to them during embryonic/early life and neurological impairments. However, our understanding of the molecular and cellular mechanism(s) underlying eEDCs exposure effects on brain development, tissue architecture and function and behaviour are limited. Transgenic (TG) zebrafish models offer new approach methodologies (NAMs) to help identify the modes of action (MoAs) of EDCs and their associated impacts on tissue development and function. Estrogen biosensor TG zebrafish models have been applied to study eEDC interactions and resulting transcriptional activation (via a fluorescent reporter expression) across the entire body of the developing zebrafish embryo, including in real time. These estrogen biosensor TG zebrafish models are starting to deepen our understanding of the spatiotemporal actions of eEDCs and their resulting impacts on neurological development, brain function and behaviour. In this review, we first investigate the links between early life exposure to eEDCs and neurodevelopmental alterations in model organisms (rodents and zebrafish) and humans. We then present examples of the application of estrogen biosensor and other TG zebrafish models for elucidating the mechanism(s) underlying neurodevelopmental toxicities of eEDCs. In particular we illustrate the utility of combining estrogen biosensor zebrafish models with other TG zebrafish models for understanding the effects of eEDCs on the brain, spanning cellular processes, brain circuitry, neurophysiology and behaviour. Finally, we discuss the future prospects of TG zebrafish models as experimental models for studying more complex scenarios for exposure to contaminant mixtures on neurological development and function.
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Affiliation(s)
- Aya Takesono
- *Correspondence: Aya Takesono, ; Charles R. Tyler,
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9
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Takesono A, Schirrmacher P, Scott A, Green JM, Lee O, Winter MJ, Kudoh T, Tyler CR. Estrogens regulate early embryonic development of the olfactory sensory system via estrogen-responsive glia. Development 2022; 149:dev199860. [PMID: 35023540 PMCID: PMC8881738 DOI: 10.1242/dev.199860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 12/02/2021] [Indexed: 01/16/2023]
Abstract
Estrogens are well-known to regulate development of sexual dimorphism of the brain; however, their role in embryonic brain development prior to sex-differentiation is unclear. Using estrogen biosensor zebrafish models, we found that estrogen activity in the embryonic brain occurs from early neurogenesis specifically in a type of glia in the olfactory bulb (OB), which we name estrogen-responsive olfactory bulb (EROB) cells. In response to estrogen, EROB cells overlay the outermost layer of the OB and interact tightly with olfactory sensory neurons at the olfactory glomeruli. Inhibiting estrogen activity using an estrogen receptor antagonist, ICI182,780 (ICI), and/or EROB cell ablation impedes olfactory glomerular development, including the topological organisation of olfactory glomeruli and inhibitory synaptogenesis in the OB. Furthermore, activation of estrogen signalling inhibits both intrinsic and olfaction-dependent neuronal activity in the OB, whereas ICI or EROB cell ablation results in the opposite effect on neuronal excitability. Altering the estrogen signalling disrupts olfaction-mediated behaviour in later larval stage. We propose that estrogens act on glia to regulate development of OB circuits, thereby modulating the local excitability in the OB and olfaction-mediated behaviour.
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Affiliation(s)
- Aya Takesono
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
| | - Paula Schirrmacher
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
- Department of Biological and Marine Sciences, Faculty of Science and Engineering, University of Hull, Hull HU6 7RX, UK
| | - Aaron Scott
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol BS8 1TD, UK
| | - Jon M Green
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
| | - Okhyun Lee
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
| | - Matthew J Winter
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
| | - Tetsuhiro Kudoh
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
| | - Charles R Tyler
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
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10
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Gilmour AD, Reshamwala R, Wright AA, Ekberg JAK, St John JA. Optimizing Olfactory Ensheathing Cell Transplantation for Spinal Cord Injury Repair. J Neurotrauma 2021; 37:817-829. [PMID: 32056492 DOI: 10.1089/neu.2019.6939] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Cell transplantation constitutes an important avenue for development of new treatments for spinal cord injury (SCI). These therapies are aimed at supporting neural repair and/or replacing lost cells at the injury site. To date, various cell types have been trialed, with most studies focusing on different types of stem cells or glial cells. Here, we review commonly used cell transplantation approaches for spinal cord injury (SCI) repair, with focus on transplantation of olfactory ensheathing cells (OECs), the glial cells of the primary olfactory nervous system. OECs are promising candidates for promotion of neural repair given that they support continuous regeneration of the olfactory nerve that occurs throughout life. Further, OECs can be accessed from the nasal mucosa (olfactory neuroepithelium) at the roof of the nasal cavity and can be autologously transplanted. OEC transplantation has been trialed in many animal models of SCI, as well as in human clinical trials. While several studies have been promising, outcomes are variable and the method needs improvement to enhance aspects such as cell survival, integration, and migration. As a case study, we include the approaches used by our team (the Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia) to address the current problems with OEC transplantation and discuss how the therapeutic potential of OEC transplantation can be improved. Our approach includes discovery research to improve our knowledge of OEC biology, identifying natural and synthetic compounds to stimulate the neural repair properties of OECs, and designing three-dimensional cell constructs to create stable and transplantable cell structures.
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Affiliation(s)
- Aaron D Gilmour
- Clem Jones Centre for Neurobiology and Stem Cell Research and Griffith University, Nathan, Queensland, Australia.,Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia
| | - Ronak Reshamwala
- Clem Jones Centre for Neurobiology and Stem Cell Research and Griffith University, Nathan, Queensland, Australia.,Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia
| | - Alison A Wright
- Clem Jones Centre for Neurobiology and Stem Cell Research and Griffith University, Nathan, Queensland, Australia.,Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia
| | - Jenny A K Ekberg
- Clem Jones Centre for Neurobiology and Stem Cell Research and Griffith University, Nathan, Queensland, Australia.,Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia
| | - James A St John
- Clem Jones Centre for Neurobiology and Stem Cell Research and Griffith University, Nathan, Queensland, Australia.,Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia
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11
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Nazareth L, St John J, Murtaza M, Ekberg J. Phagocytosis by Peripheral Glia: Importance for Nervous System Functions and Implications in Injury and Disease. Front Cell Dev Biol 2021; 9:660259. [PMID: 33898462 PMCID: PMC8060502 DOI: 10.3389/fcell.2021.660259] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/17/2021] [Indexed: 12/30/2022] Open
Abstract
The central nervous system (CNS) has very limited capacity to regenerate after traumatic injury or disease. In contrast, the peripheral nervous system (PNS) has far greater capacity for regeneration. This difference can be partly attributed to variances in glial-mediated functions, such as axon guidance, structural support, secretion of growth factors and phagocytic activity. Due to their growth-promoting characteristic, transplantation of PNS glia has been trialed for neural repair. After peripheral nerve injuries, Schwann cells (SCs, the main PNS glia) phagocytose myelin debris and attract macrophages to the injury site to aid in debris clearance. One peripheral nerve, the olfactory nerve, is unique in that it continuously regenerates throughout life. The olfactory nerve glia, olfactory ensheathing cells (OECs), are the primary phagocytes within this nerve, continuously clearing axonal debris arising from the normal regeneration of the nerve and after injury. In contrast to SCs, OECs do not appear to attract macrophages. SCs and OECs also respond to and phagocytose bacteria, a function likely critical for tackling microbial invasion of the CNS via peripheral nerves. However, phagocytosis is not always effective; inflammation, aging and/or genetic factors may contribute to compromised phagocytic activity. Here, we highlight the diverse roles of SCs and OECs with the focus on their phagocytic activity under physiological and pathological conditions. We also explore why understanding the contribution of peripheral glia phagocytosis may provide us with translational strategies for achieving axonal regeneration of the injured nervous system and potentially for the treatment of certain neurological diseases.
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Affiliation(s)
- Lynn Nazareth
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia.,Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia
| | - James St John
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia.,Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Mariyam Murtaza
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia.,Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Jenny Ekberg
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia.,Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia.,Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
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12
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Smedlund KB, Hill JW. The role of non-neuronal cells in hypogonadotropic hypogonadism. Mol Cell Endocrinol 2020; 518:110996. [PMID: 32860862 DOI: 10.1016/j.mce.2020.110996] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/01/2020] [Accepted: 08/16/2020] [Indexed: 12/18/2022]
Abstract
The hypothalamic-pituitary-gonadal axis is controlled by gonadotropin-releasing hormone (GnRH) released by the hypothalamus. Disruption of this system leads to impaired reproductive maturation and function, a condition known as hypogonadotropic hypogonadism (HH). Most studies to date have focused on genetic causes of HH that impact neuronal development and function. However, variants may also impact the functioning of non-neuronal cells known as glia. Glial cells make up 50% of brain cells of humans, primates, and rodents. They include radial glial cells, microglia, astrocytes, tanycytes, oligodendrocytes, and oligodendrocyte precursor cells. Many of these cells influence the hypothalamic neuroendocrine system controlling fertility. Indeed, glia regulate GnRH neuronal activity and secretion, acting both at their cell bodies and their nerve endings. Recent work has also made clear that these interactions are an essential aspect of how the HPG axis integrates endocrine, metabolic, and environmental signals to control fertility. Recognition of the clinical importance of interactions between glia and the GnRH network may pave the way for the development of new treatment strategies for dysfunctions of puberty and adult fertility.
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Affiliation(s)
- Kathryn B Smedlund
- Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA; Center for Diabetes and Endocrine Research, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA
| | - Jennifer W Hill
- Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA; Center for Diabetes and Endocrine Research, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, 43614, USA.
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13
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Aleo S, Cinnante C, Avignone S, Prada E, Scuvera G, Ajmone PF, Selicorni A, Costantino MA, Triulzi F, Marchisio P, Gervasini C, Milani D. Olfactory Malformations in Mendelian Disorders of the Epigenetic Machinery. Front Cell Dev Biol 2020; 8:710. [PMID: 32850830 PMCID: PMC7417603 DOI: 10.3389/fcell.2020.00710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/13/2020] [Indexed: 11/13/2022] Open
Abstract
Usually overlooked by physicians, olfactory abnormalities are not uncommon. Olfactory malformations have recently been reported in an emerging group of genetic disorders called Mendelian Disorders of the Epigenetic Machinery (MDEM). This study aims to determine the prevalence of olfactory malformations in a heterogeneous group of subjects with MDEM. We reviewed the clinical data of 35 patients, 20 females and 15 males, with a mean age of 9.52 years (SD 4.99). All patients had a MDEM and an already available high-resolution brain MRI scan. Two experienced neuroradiologists reviewed the MR images, noting abnormalities and classifying olfactory malformations. Main findings included Corpus Callosum, Cerebellar vermis, and olfactory defects. The latter were found in 11/35 cases (31.4%), of which 7/11 had Rubinstein-Taybi syndrome (RSTS), 2/11 had CHARGE syndrome, 1/11 had Kleefstra syndrome (KLFS), and 1/11 had Weaver syndrome (WVS). The irregularities mainly concerned the olfactory bulbs and were bilateral in 9/11 patients. With over 30% of our sample having an olfactory malformation, this study reveals a possible new diagnostic marker for MDEM and links the epigenetic machinery to the development of the olfactory bulbs.
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Affiliation(s)
- Sebastiano Aleo
- Pediatric Highly Intensive Care Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Claudia Cinnante
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neuroradiology Unit, Università degli Studi di Milano, Milan, Italy
| | - Sabrina Avignone
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neuroradiology Unit, Università degli Studi di Milano, Milan, Italy
| | - Elisabetta Prada
- Pediatric Highly Intensive Care Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Giulietta Scuvera
- Pediatric Highly Intensive Care Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Paola Francesca Ajmone
- Child and Adolescent Neuropsychiatric Service (UONPIA), Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | | | - Maria Antonella Costantino
- Child and Adolescent Neuropsychiatric Service (UONPIA), Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Fabio Triulzi
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neuroradiology Unit, Università degli Studi di Milano, Milan, Italy
| | - Paola Marchisio
- Pediatric Highly Intensive Care Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Cristina Gervasini
- Division of Medical Genetics, Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Donatella Milani
- Pediatric Highly Intensive Care Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
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14
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Jeong SK, Choi I, Jeon SR. Current Status and Future Strategies to Treat Spinal Cord Injury with Adult Stem Cells. J Korean Neurosurg Soc 2019; 63:153-162. [PMID: 31805758 PMCID: PMC7054109 DOI: 10.3340/jkns.2019.0146] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Accepted: 09/17/2019] [Indexed: 02/07/2023] Open
Abstract
Spinal cord injury (SCI) is one of the most devastating conditions and many SCI patients suffer neurological sequelae. Stem cell therapies are expected to be beneficial for many patients with central nervous system injuries, including SCI. Adult stem cells (ASCs) are not associated with the risks which embryonic stem cells have such as malignant transformation, or ethical problems, and can be obtained relatively easily. Consequently, many researchers are currently studying the effects of ASCs in clinical trials. The environment of transplanted cells applied in the injured spinal cord differs between the phases of SCI; therefore, many researchers have investigated these phases to determine the optimal time window for stem cell therapy in animals. In addition, the results of clinical trials should be evaluated according to the phase in which stem cells are transplanted. In general, the subacute phase is considered to be optimal for stem cell transplantation. Among various candidates of transplantable ASCs, mesenchymal stem cells (MSCs) are most widely studied due to their clinical safety. MSCs are also less immunogenic than neural stem/progenitor cells and consequently immunosuppressants are rarely required. Attempts have been made to enhance the effects of stem cells using scaffolds, trophic factors, cytokines, and other drugs in animal and/or human clinical studies. Over the past decade, several clinical trials have suggested that transplantation of MSCs into the injured spinal cord elicits therapeutic effects on SCI and is safe; however, the clinical effects are limited at present. Therefore, new therapeutic agents, such as genetically enhanced stem cells which effectively secrete neurotrophic factors or cytokines, must be developed based on the safety of pure MSCs.
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Affiliation(s)
- Seong Kyun Jeong
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Il Choi
- Department of Neurological Surgery, Hallym University Dongtan Sacred Heart Hospital, Hwaseong, Korea
| | - Sang Ryong Jeon
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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15
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Reshamwala R, Shah M, St John J, Ekberg J. Survival and Integration of Transplanted Olfactory Ensheathing Cells are Crucial for Spinal Cord Injury Repair: Insights from the Last 10 Years of Animal Model Studies. Cell Transplant 2019; 28:132S-159S. [PMID: 31726863 PMCID: PMC7016467 DOI: 10.1177/0963689719883823] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/03/2019] [Accepted: 09/27/2019] [Indexed: 12/15/2022] Open
Abstract
Olfactory ensheathing cells (OECs), the glial cells of the primary olfactory nervous system, support the natural regeneration of the olfactory nerve that occurs throughout life. OECs thus exhibit unique properties supporting neuronal survival and growth. Transplantation of OECs is emerging as a promising treatment for spinal cord injury; however, outcomes in both animals and humans are variable and the method needs improvement and standardization. A major reason for the discrepancy in functional outcomes is the variability in survival and integration of the transplanted cells, key factors for successful spinal cord regeneration. Here, we review the outcomes of OEC transplantation in rodent models over the last 10 years, with a focus on survival and integration of the transplanted cells. We identify the key factors influencing OEC survival: injury type, source of transplanted cells, co-transplantation with other cell types, number and concentration of cells, method of delivery, and time of transplantation after the injury. We found that two key issues are hampering optimization and standardization of OEC transplantation: lack of (1) reliable methods for identifying transplanted cells, and (2) three-dimensional systems for OEC delivery. To develop OEC transplantation as a successful and standardized therapy for spinal cord injury, we must address these issues and increase our understanding of the complex parameters influencing OEC survival.
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Affiliation(s)
- Ronak Reshamwala
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia
- Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Brisbane, Queensland, Australia
| | - Megha Shah
- Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Brisbane, Queensland, Australia
| | - James St John
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia
- Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Brisbane, Queensland, Australia
| | - Jenny Ekberg
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia
- Menzies Health Institute Queensland, Griffith University, Southport, Queensland, Australia
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Brisbane, Queensland, Australia
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16
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Piantanida AP, Acosta LE, Brocardo L, Capurro C, Greer CA, Rela L. Selective Cre-mediated gene deletion identifies connexin 43 as the main connexin channel supporting olfactory ensheathing cell networks. J Comp Neurol 2019; 527:1278-1289. [PMID: 30628061 DOI: 10.1002/cne.24628] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/27/2018] [Accepted: 01/02/2019] [Indexed: 02/07/2023]
Abstract
Many functions of glial cells depend on the formation of selective glial networks mediated by gap junctions formed by members of the connexin family. Olfactory ensheathing cells (OECs) are specialized glia associated with olfactory sensory neuron axons. Like other glia, they form selective networks, however, the connexins that support OEC connectivity in vivo have not been identified. We used an in vivo mouse model to selectively delete candidate connexin genes with temporal control from OECs and address the physiological consequences. Using this model, we effectively abolished the expression of connexin 43 (Cx43) in OECs in both juvenile and adult mice. Cx43-deleted OECs exhibited features consistent with the loss of gap junctions including reduced membrane conductance, largely reduced sensitivity to the gap junction blocker meclofenamic acid and loss of dye coupling. This indicates that Cx43, a typically astrocytic connexin, is the main connexin forming functional channels in OECs. Despite these changes in functional properties, the deletion of Cx43 deletion did not alter the density of OECs. The strategy used here may prove useful to delete other candidate genes to better understand the functional roles of OECs in vivo.
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Affiliation(s)
- Ana Paula Piantanida
- CONICET, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina.,Universidad de Buenos Aires, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina
| | - Luis Ernesto Acosta
- CONICET, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina.,Universidad de Buenos Aires, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina
| | - Lucila Brocardo
- CONICET, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina.,Universidad de Buenos Aires, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina
| | - Claudia Capurro
- CONICET, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina.,Universidad de Buenos Aires, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina
| | - Charles A Greer
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut.,Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut
| | - Lorena Rela
- CONICET, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina.,Universidad de Buenos Aires, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Neurociencia de Sistemas, Buenos Aires, Argentina
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17
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Nazareth L, Chen M, Shelper T, Shah M, Tello Velasquez J, Walkden H, Beacham I, Batzloff M, Rayfield A, Todorovic M, Beagley KW, St John JA, Ekberg JAK. Novel insights into the glia limitans of the olfactory nervous system. J Comp Neurol 2019; 527:1228-1244. [PMID: 30592044 DOI: 10.1002/cne.24618] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 12/14/2018] [Accepted: 12/14/2018] [Indexed: 02/04/2023]
Abstract
Olfactory ensheathing cells (OECs) are often described as being present in both the peripheral and the central nervous systems (PNS and CNS). Furthermore, the olfactory nervous system glia limitans (the glial layer defining the PNS-CNS border) is considered unique as it consists of intermingling OECs and astrocytes. In contrast, the glia limitans of the rest of the nervous system consists solely of astrocytes which create a distinct barrier to Schwann cells (peripheral glia). The ability of OECs to interact with astrocytes is one reason why OECs are believed to be superior to Schwann cells for transplantation therapies to treat CNS injuries. We have used transgenic reporter mice in which glial cells express DsRed fluorescent protein to study the cellular constituents of the glia limitans. We found that the glia limitans layer of the olfactory nervous system is morphologically similar to elsewhere in the nervous system, with a similar low degree of intermingling between peripheral glia and astrocytes. We found that the astrocytic layer of the olfactory bulb is a distinct barrier to bacterial infection, suggesting that this layer constitutes the PNS-CNS immunological barrier. We also found that OECs interact with astrocytes in a similar fashion as Schwann cells in vitro. When cultured in three dimensions, however, there were subtle differences between OECs and Schwann cells in their interactions with astrocytes. We therefore suggest that glial fibrillary acidic protein-reactive astrocyte layer of the olfactory bulb constitutes the glia limitans of the olfactory nervous system and that OECs are primarily "PNS glia."
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Affiliation(s)
- Lynn Nazareth
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia
| | - Mo Chen
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia
| | - Todd Shelper
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia
| | - Megha Shah
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia
| | - Johana Tello Velasquez
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Institute for Glycomics, Griffith University, Southport, Queensland, Australia
| | - Heidi Walkden
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia
| | - Ifor Beacham
- Institute for Glycomics, Griffith University, Southport, Queensland, Australia
| | - Michael Batzloff
- Institute for Glycomics, Griffith University, Southport, Queensland, Australia
| | - Andrew Rayfield
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia
| | - Michael Todorovic
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia.,School of Nursing and Midwifery, Griffith University, Nathan, Queensland, Australia
| | - Kenneth W Beagley
- Institute for Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - James A St John
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia.,Institute for Glycomics, Griffith University, Southport, Queensland, Australia
| | - Jenny A K Ekberg
- Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia.,Menzies Institute of Health Queensland, Griffith University, Southport, Queensland, Australia
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18
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Rich CA, Perera SN, Andratschke J, Stolt CC, Buehler DP, Southard-Smith EM, Wegner M, Britsch S, Baker CVH. Olfactory ensheathing cells abutting the embryonic olfactory bulb express Frzb, whose deletion disrupts olfactory axon targeting. Glia 2018; 66:2617-2631. [PMID: 30256452 PMCID: PMC6517278 DOI: 10.1002/glia.23515] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 07/19/2018] [Accepted: 07/30/2018] [Indexed: 12/11/2022]
Abstract
We and others previously showed that in mouse embryos lacking the transcription factor Sox10, olfactory ensheathing cell (OEC) differentiation is disrupted, resulting in defective olfactory axon targeting and fewer gonadotropin‐releasing hormone (GnRH) neurons entering the embryonic forebrain. The underlying mechanisms are unclear. Here, we report that OECs in the olfactory nerve layer express Frzb—encoding a secreted Wnt inhibitor with roles in axon targeting and basement membrane breakdown—from embryonic day (E)12.5, when GnRH neurons first enter the forebrain, until E16.5, the latest stage examined. The highest levels of Frzb expression are seen in OECs in the inner olfactory nerve layer, abutting the embryonic olfactory bulb. We find that Sox10 is required for Frzb expression in OECs, suggesting that loss of Frzb could explain the olfactory axon targeting and/or GnRH neuron migration defects seen in Sox10‐null mice. At E16.5, Frzb‐null embryos show significant reductions in both the volume of the olfactory nerve layer expressing the maturation marker Omp and the number of Omp‐positive olfactory receptor neurons in the olfactory epithelium. As Omp upregulation correlates with synapse formation, this suggests that Frzb deletion indeed disrupts olfactory axon targeting. In contrast, GnRH neuron entry into the forebrain is not significantly affected. Hence, loss of Frzb may contribute to the olfactory axon targeting phenotype, but not the GnRH neuron phenotype, of Sox10‐null mice. Overall, our results suggest that Frzb secreted from OECs in the olfactory nerve layer is important for olfactory axon targeting. Frzb is expressed by olfactory ensheathing cells abutting the embryonic mouse olfactory bulb. Frzb expression requires Sox10. Deletion of Frzb disrupts olfactory receptor neuron maturation, likely reflecting a defect in olfactory axon targeting.
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Affiliation(s)
- Constance A Rich
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Surangi N Perera
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | | | - C Claus Stolt
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Dennis P Buehler
- Division of Genetic Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - E Michelle Southard-Smith
- Division of Genetic Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Michael Wegner
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Stefan Britsch
- Institute of Molecular and Cellular Anatomy, Ulm University, Ulm, Germany
| | - Clare V H Baker
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
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19
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Semaphorin 3A as an inhibitive factor for migration of olfactory ensheathing cells through cofilin activation is involved in formation of olfactory nerve layer. Mol Cell Neurosci 2018; 92:27-39. [PMID: 29940213 DOI: 10.1016/j.mcn.2018.06.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 05/23/2018] [Accepted: 06/19/2018] [Indexed: 01/27/2023] Open
Abstract
Olfactory ensheathing cells (OECs) migrate from olfactory epithelium towards olfactory bulb (OB), contributing to formation of the presumptive olfactory nerve layer during development. However, it remains unclear that molecular mechanism of regulation of OEC migration in OB. In the present study, we found that OECs highly expressed the receptors of semaphorin 3A (Sema3A) in vitro and in vivo, whereas Sema3A displayed a gradient expression pattern with higher in inner layer of OB and lower in outer layer of OB. Furthermore, the collapse assays, Boyden chamber migration assays and single-cell migration assays showed that Sema3A induced the collapse of leading front of OECs and inhibited OEC migration. Thirdly, the leading front of OECs exhibited adaptation in a protein synthesis-independent manner, and endocytosis-dependent manner during Sema3A-induced OEC migration. Finally, Sema3A-induced collapse of leading front was required the decrease of focal adhesion and a retrograde F-actin flow in a cofilin activation-dependent manner. Taken together, these results demonstrate that Sema3A as an inhibitive migratory factor for OEC migration through cofilin activation is involved in the formation of olfactory nerve layer.
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20
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Sokpor G, Abbas E, Rosenbusch J, Staiger JF, Tuoc T. Transcriptional and Epigenetic Control of Mammalian Olfactory Epithelium Development. Mol Neurobiol 2018. [PMID: 29532253 DOI: 10.1007/s12035-018-0987-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The postnatal mammalian olfactory epithelium (OE) represents a major aspect of the peripheral olfactory system. It is a pseudostratified tissue that originates from the olfactory placode and is composed of diverse cells, some of which are specialized receptor neurons capable of transducing odorant stimuli to afford the perception of smell (olfaction). The OE is known to offer a tractable miniature model for studying the systematic generation of neurons and glia that typify neural tissue development. During OE development, stem/progenitor cells that will become olfactory sensory neurons and/or non-neuronal cell types display fine spatiotemporal expression of neuronal and non-neuronal genes that ensures their proper proliferation, differentiation, survival, and regeneration. Many factors, including transcription and epigenetic factors, have been identified as key regulators of the expression of such requisite genes to permit normal OE morphogenesis. Typically, specific interactive regulatory networks established between transcription and epigenetic factors/cofactors orchestrate histogenesis in the embryonic and adult OE. Hence, investigation of these regulatory networks critical for OE development promises to disclose strategies that may be employed in manipulating the stepwise transition of olfactory precursor cells to become fully differentiated and functional neuronal and non-neuronal cell types. Such strategies potentially offer formidable means of replacing injured or degenerated neural cells as therapeutics for nervous system perturbations. This review recapitulates the developmental cellular diversity of the olfactory neuroepithelium and discusses findings on how the precise and cooperative molecular control by transcriptional and epigenetic machinery is indispensable for OE ontogeny.
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Affiliation(s)
- Godwin Sokpor
- Institute of Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany
| | - Eman Abbas
- Institute of Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany.,Zoology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Joachim Rosenbusch
- Institute of Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany
| | - Jochen F Staiger
- Institute of Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany.,DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), 37075, Goettingen, Germany
| | - Tran Tuoc
- Institute of Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany. .,DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), 37075, Goettingen, Germany.
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21
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Gómez RM, Sánchez MY, Portela-Lomba M, Ghotme K, Barreto GE, Sierra J, Moreno-Flores MT. Cell therapy for spinal cord injury with olfactory ensheathing glia cells (OECs). Glia 2018; 66:1267-1301. [PMID: 29330870 DOI: 10.1002/glia.23282] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 11/20/2017] [Accepted: 11/28/2017] [Indexed: 01/18/2023]
Abstract
The prospects of achieving regeneration in the central nervous system (CNS) have changed, as most recent findings indicate that several species, including humans, can produce neurons in adulthood. Studies targeting this property may be considered as potential therapeutic strategies to respond to injury or the effects of demyelinating diseases in the CNS. While CNS trauma may interrupt the axonal tracts that connect neurons with their targets, some neurons remain alive, as seen in optic nerve and spinal cord (SC) injuries (SCIs). The devastating consequences of SCIs are due to the immediate and significant disruption of the ascending and descending spinal pathways, which result in varying degrees of motor and sensory impairment. Recent therapeutic studies for SCI have focused on cell transplantation in animal models, using cells capable of inducing axon regeneration like Schwann cells (SchCs), astrocytes, genetically modified fibroblasts and olfactory ensheathing glia cells (OECs). Nevertheless, and despite the improvements in such cell-based therapeutic strategies, there is still little information regarding the mechanisms underlying the success of transplantation and regarding any secondary effects. Therefore, further studies are needed to clarify these issues. In this review, we highlight the properties of OECs that make them suitable to achieve neuroplasticity/neuroregeneration in SCI. OECs can interact with the glial scar, stimulate angiogenesis, axon outgrowth and remyelination, improving functional outcomes following lesion. Furthermore, we present evidence of the utility of cell therapy with OECs to treat SCI, both from animal models and clinical studies performed on SCI patients, providing promising results for future treatments.
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Affiliation(s)
- Rosa M Gómez
- Fundación de Neuroregeneración en Colombia, Grupo de investigación NeuroRec, Bogota D.C, Colombia
| | - Magdy Y Sánchez
- Fundación de Neuroregeneración en Colombia, Grupo de investigación NeuroRec, Bogota D.C, Colombia.,Maestría en Neurociencias, Universidad Nacional de Colombia, Bogota D.C, Colombia
| | - Maria Portela-Lomba
- Facultad de CC Experimentales, Universidad Francisco de Vitoria, Pozuelo de Alarcón, Madrid, Spain
| | - Kemel Ghotme
- Facultad de Medicina, Universidad de la Sabana, Chía, Colombia
| | - George E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogota D.C, Colombia.,Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Javier Sierra
- Facultad de CC Experimentales, Universidad Francisco de Vitoria, Pozuelo de Alarcón, Madrid, Spain
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22
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Geller S, Lomet D, Caraty A, Tillet Y, Duittoz A, Vaudin P. Rostro-caudal maturation of glial cells in the accessory olfactory system during development: involvement in outgrowth of GnRH neurites. Eur J Neurosci 2017; 46:2596-2607. [PMID: 28973792 DOI: 10.1111/ejn.13732] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 09/27/2017] [Accepted: 09/27/2017] [Indexed: 01/21/2023]
Abstract
During mammalian embryonic development, GnRH neurones differentiate from the nasal placode and migrate through the nasal septum towards the forebrain. We previously showed that a category of glial cells, the olfactory ensheathing cells (OEC), forms the microenvironment of migrating GnRH neurones. Here, to characterize the quantitative and qualitative importance of this glial, we investigated the spatiotemporal maturation of glial cells in situ and the role of maturing glia in GnRH neurones development ex vivo. More than 90% of migrating GnRH neurones were found to be associated with glial cells. There was no change in the cellular microenvironment of GnRH neurones in the regions crossed during embryonic development as glial cells formed the main microenvironment of these neurones (53.4%). However, the phenotype of OEC associated with GnRH neurones changed across regions. The OEC progenitors immunoreactive to brain lipid binding protein formed the microenvironment of migrating GnRH neurones from the vomeronasal organ to the telencephalon and were also present in the diencephalon. However, during GnRH neurone migration, maturation of OEC to [GFAP+] state (glial fibrillary acid protein) was only observed in the nasal septum. Inducing depletion of OEC in maturation, using transgenic mice expressing herpes simplex virus thymidine kinase driven by the GFAP promoter, had no impact on neurogenesis or on triggering GnRH neurones migration in nasal explant culture. Nevertheless, depletion of [GFAP+] cells decreased GnRH neurites outgrowth by 57.4%. This study suggests that specific maturation of OEC in the nasal septum plays a role in morphological differentiation of GnRH neurones.
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Affiliation(s)
- Sarah Geller
- Physiologie de la Reproduction et des Comportements, UMR 0085 INRA, 7247 CNRS, Université François Rabelais de Tours, IFCE, SFR FED4226 Neuroimagerie, 37380, Nouzilly, France
| | - Didier Lomet
- Physiologie de la Reproduction et des Comportements, UMR 0085 INRA, 7247 CNRS, Université François Rabelais de Tours, IFCE, SFR FED4226 Neuroimagerie, 37380, Nouzilly, France
| | - Alain Caraty
- Physiologie de la Reproduction et des Comportements, UMR 0085 INRA, 7247 CNRS, Université François Rabelais de Tours, IFCE, SFR FED4226 Neuroimagerie, 37380, Nouzilly, France
| | - Yves Tillet
- Physiologie de la Reproduction et des Comportements, UMR 0085 INRA, 7247 CNRS, Université François Rabelais de Tours, IFCE, SFR FED4226 Neuroimagerie, 37380, Nouzilly, France
| | - Anne Duittoz
- Physiologie de la Reproduction et des Comportements, UMR 0085 INRA, 7247 CNRS, Université François Rabelais de Tours, IFCE, SFR FED4226 Neuroimagerie, 37380, Nouzilly, France
| | - Pascal Vaudin
- Physiologie de la Reproduction et des Comportements, UMR 0085 INRA, 7247 CNRS, Université François Rabelais de Tours, IFCE, SFR FED4226 Neuroimagerie, 37380, Nouzilly, France
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23
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Zheng CG, Zhang F, Bao XM, Wu SY, Wang P, Zhou JN, Gao Y, Teng HL, Wang Y, Huang ZH. Polarized Distribution of Active Myosin II Regulates Directional Migration of Cultured Olfactory Ensheathing Cells. Sci Rep 2017; 7:4701. [PMID: 28680155 PMCID: PMC5498622 DOI: 10.1038/s41598-017-04914-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 05/22/2017] [Indexed: 11/09/2022] Open
Abstract
Migration of olfactory ensheathing cells (OECs) is critical for development of olfactory system and essential for neural regeneration after OEC transplantation into nerve injury site. However, the molecular mechanisms underlying the regulation of directional migration of OECs remain unclear. In this study, we found that in migrating OECs, phosphorylated myosin light chain (p-MLC, active myosin II) displayed a polarized distribution, with the leading front exhibiting higher than soma and trailing process. Over-expression of GFP-MLC significantly reduced OEC migration. Moreover, decreasing this front-to-rear difference of myosin II activity by the frontal application of a ML-7 (myosin II inhibitors) gradient induced the collapse of leading front and reversed soma translocation of OECs, whereas, increasing this front-to-rear difference of myosin II activity by the rear application of a ML-7 or BDM gradient or the frontal application of a Caly (myosin II activator) gradient accelerated the soma translocation of OECs. Finally, myosin II as a downstream signaling of repulsive factor Slit-2 mediated the reversal of soma translocation induced by Slit-2. Taken together, these results suggest that the polarized distribution of active myosin II regulates the directional migration of OECs during spontaneous migration or upon to extracellular stimulation such as Slit-2.
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Affiliation(s)
- Cheng-Gen Zheng
- Department of Cardiology, Chun'an First People's Hospital (Zhejiang Province People's Hospital Chun'an Branch), Hangzhou, 311700, China
| | - Fan Zhang
- Institute of Neuroscience and Institute of Hypoxia Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Xiao-Mei Bao
- Institute of Neuroscience and Institute of Hypoxia Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Shi-Yang Wu
- Department of Spine Surgery, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Peng Wang
- Department of Spine Surgery, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Jia-Nan Zhou
- Institute of Neuroscience and Institute of Hypoxia Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Yuan Gao
- Institute of Neuroscience and Institute of Hypoxia Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Hong-Lin Teng
- Department of Spine Surgery, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.
| | - Ying Wang
- Department of Cardiology, Chun'an First People's Hospital (Zhejiang Province People's Hospital Chun'an Branch), Hangzhou, 311700, China. .,Institute of Neuroscience and Institute of Hypoxia Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China. .,Department of Transfusion Medicine, Zhejiang Provincial People's Hospital of Hangzhou Medical College, Hangzhou, 310053, China.
| | - Zhi-Hui Huang
- Institute of Neuroscience and Institute of Hypoxia Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.
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Monjaraz-Fuentes F, Millán-Adalco D, Palomero-Rivero M, Hudson R, Drucker-Colín R. Recovery of glomerular morphology in the olfactory bulb of young mice after disruption caused by continuous odorant exposure. Brain Res 2017; 1670:6-13. [PMID: 28583862 DOI: 10.1016/j.brainres.2017.05.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/17/2017] [Accepted: 05/27/2017] [Indexed: 01/14/2023]
Abstract
Olfactory glomeruli are the first synaptic site of the olfactory system and are formed by the convergence of axons of the same type of sensory neurons onto the olfactory bulbs of the brain. Although the anatomical organization of glomeruli is conserved across species, their particular role in olfactory processing remains uncertain. We studied the composition and maintenance of glomeruli by means of a genetic model, mI7-IRES-tauGFP knock-in young mice, where the cytoskeleton of sensory neurons expressing the mI7 olfactory receptor is tagged with green fluorescent protein. Animals were continuously exposed to heptaldehyde, a cognate ligand of the mI7 receptor, from postnatal days 5-10. We hypothesized that continuous odorant exposure will induce changes in glomerular morphology, and that this can be recovered if the normal odorant environment is reestablished within the early postnatal period. We assessed changes in the distribution of mI7 axons in glomerular morphology, as well as possible changes in the number of the mI7 olfactory sensory neurons. Following odorant exposure the well-defined convergence of mI7 fibers into a single glomerulus was disrupted, producing numerous neighboring glomeruli partially innervated by mI7 fibers. After the normal odor environment was reestablished the number of glomeruli partially innervated by mI7 fibers decreased significantly. Moreover, we found that multiple supernumerary mI7 glomeruli were formed. Our results confirm the significant role of sensory input in glomerular formation and maintenance. Additionally, we show that the developing olfactory system actively maintains glomerular morphology, suggesting the importance of this for olfactory processing.
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Affiliation(s)
- Fernanda Monjaraz-Fuentes
- División de Neurociencias, Departamento de Neuropatología Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, CP 04510 Ciudad de México, Mexico.
| | - Diana Millán-Adalco
- División de Neurociencias, Departamento de Neuropatología Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, CP 04510 Ciudad de México, Mexico.
| | - Marcela Palomero-Rivero
- División de Neurociencias, Departamento de Neuropatología Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, CP 04510 Ciudad de México, Mexico.
| | - Robyn Hudson
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, AP 70228, CP 04510 Ciudad de México, Mexico.
| | - René Drucker-Colín
- División de Neurociencias, Departamento de Neuropatología Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, CP 04510 Ciudad de México, Mexico.
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25
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Casoni F, Malone SA, Belle M, Luzzati F, Collier F, Allet C, Hrabovszky E, Rasika S, Prevot V, Chédotal A, Giacobini P. Development of the neurons controlling fertility in humans: new insights from 3D imaging and transparent fetal brains. Development 2016; 143:3969-3981. [DOI: 10.1242/dev.139444] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 09/05/2016] [Indexed: 12/12/2022]
Abstract
Fertility in mammals is controlled by hypothalamic neurons that secrete gonadotropin-releasing hormone (GnRH). These neurons differentiate in the olfactory placodes during embryogenesis and migrate from the nose to the hypothalamus before birth. Information regarding this process in humans is sparse. Here, we adapted new tissue-clearing and whole-mount immunohistochemical techniques to entire human embryos/fetuses to meticulously study this system during the first trimester of gestation in the largest series of human fetuses examined to date. Combining these cutting-edge techniques with conventional immunohistochemistry, we provide the first chronological and quantitative analysis of GnRH neuron origins, differentiation and migration, as well as a 3D atlas of their distribution in the fetal brain. We reveal not only that the number of GnRH-immunoreactive neurons in humans is significantly higher than previously thought, but that GnRH cells migrate into several extrahypothalamic brain regions in addition to the hypothalamus. Their presence in these areas raises the possibility that GnRH has non-reproductive roles, creating new avenues for research on GnRH functions in cognitive, behavioral and physiological processes.
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Affiliation(s)
- Filippo Casoni
- University of Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille 59000, France
- Inserm, UMR-S 1172, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille 59000, France
| | - Samuel A. Malone
- University of Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille 59000, France
- Inserm, UMR-S 1172, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille 59000, France
| | - Morgane Belle
- Sorbonne Université, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, Paris 75012, France
| | - Federico Luzzati
- Department of Life Sciences and Systems Biology (DBIOS), University of Turin, Turin 10123, Italy
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano 10043, Italy
| | - Francis Collier
- FHU 1,000 Days for Health, University of Lille, School of Medicine, Lille 5900, France
- CHU Lille, Gynaecology Service - Hospital Jeanne de Flandre, Lille 59000, France
| | - Cecile Allet
- University of Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille 59000, France
- Inserm, UMR-S 1172, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille 59000, France
| | - Erik Hrabovszky
- Institute of Experimental Medicine, Laboratory of Endocrine Neurobiology, Budapest 1083, Hungary
| | | | - Vincent Prevot
- University of Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille 59000, France
- Inserm, UMR-S 1172, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille 59000, France
- FHU 1,000 Days for Health, University of Lille, School of Medicine, Lille 5900, France
| | - Alain Chédotal
- Sorbonne Université, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, Paris 75012, France
| | - Paolo Giacobini
- University of Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille 59000, France
- Inserm, UMR-S 1172, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille 59000, France
- FHU 1,000 Days for Health, University of Lille, School of Medicine, Lille 5900, France
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26
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Jaafar C, Omais S, Al Lafi S, El Jamal N, Noubani M, Skaf L, Ghanem N. Role of Rb during Neurogenesis and Axonal Guidance in the Developing Olfactory System. Front Mol Neurosci 2016; 9:81. [PMID: 27667971 PMCID: PMC5016521 DOI: 10.3389/fnmol.2016.00081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 08/24/2016] [Indexed: 11/19/2022] Open
Abstract
The Retinoblastoma protein, Rb, was shown to regulate distinct aspects of neurogenesis in the embryonic and adult brain besides its primary role in cell cycle control. It is still unknown, however, whether Rb is required for tissue morphogenesis and the establishment of synaptic connections between adjacent tissues during development. We have investigated here the role of Rb during development of the olfactory system (OS), which heavily relies on reciprocal interactions between the olfactory epithelium (OE) and the olfactory bulb (OB). We show that mice carrying a telencephalic-specific deletion of Rb display several neurogenic defects in the OS during late development. In the OE, loss of Rb leads to ectopic proliferation of late-born progenitors (Tuj-1+), abnormal radial migration and terminal maturation of olfactory sensory neurons (OSNs). In the OB, deletion of Rb causes severe lamination defects with loss of clear boundaries between distinct layers. Importantly, starting around E15.5 when OB glomerulogenesis is initiated, many OSNs axons that project along the olfactory nerve layer (ONL) fail to properly innervate the nascent bulb, thus resulting in partial loss of connectivity between OE-OB and gradual neuronal degeneration in both tissues peaking at birth. This deficiency correlates with deregulated expressions of two key chemo-repellant molecules, Robo2/Slit1 and Nrp2/Sema3F that control the formation of dorsal-ventral topographic map of OSNs connections with OB glomeruli. This study highlights a critical requirement for Rb during neurogenesis and the establishment of proper synaptic connections inside the OS during development.
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Affiliation(s)
- Carine Jaafar
- Department of Biology, American University of Beirut Beirut, Lebanon
| | - Saad Omais
- Department of Biology, American University of Beirut Beirut, Lebanon
| | - Sawsan Al Lafi
- Department of Biology, American University of Beirut Beirut, Lebanon
| | - Nadim El Jamal
- Department of Biology, American University of Beirut Beirut, Lebanon
| | - Mohammad Noubani
- Department of Biology, American University of Beirut Beirut, Lebanon
| | - Larissa Skaf
- Department of Biology, American University of Beirut Beirut, Lebanon
| | - Noël Ghanem
- Department of Biology, American University of Beirut Beirut, Lebanon
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27
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Huilgol D, Tole S. Cell migration in the developing rodent olfactory system. Cell Mol Life Sci 2016; 73:2467-90. [PMID: 26994098 PMCID: PMC4894936 DOI: 10.1007/s00018-016-2172-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Revised: 02/08/2016] [Accepted: 03/01/2016] [Indexed: 02/06/2023]
Abstract
The components of the nervous system are assembled in development by the process of cell migration. Although the principles of cell migration are conserved throughout the brain, different subsystems may predominantly utilize specific migratory mechanisms, or may display unusual features during migration. Examining these subsystems offers not only the potential for insights into the development of the system, but may also help in understanding disorders arising from aberrant cell migration. The olfactory system is an ancient sensory circuit that is essential for the survival and reproduction of a species. The organization of this circuit displays many evolutionarily conserved features in vertebrates, including molecular mechanisms and complex migratory pathways. In this review, we describe the elaborate migrations that populate each component of the olfactory system in rodents and compare them with those described in the well-studied neocortex. Understanding how the components of the olfactory system are assembled will not only shed light on the etiology of olfactory and sexual disorders, but will also offer insights into how conserved migratory mechanisms may have shaped the evolution of the brain.
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Affiliation(s)
- Dhananjay Huilgol
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
- Cold Spring Harbor Laboratory, Cold Spring Harbor, USA
| | - Shubha Tole
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India.
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28
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Gómez RM, Ghotme K, Botero L, Bernal JE, Pérez R, Barreto GE, Bustos RH. Ultrastructural analysis of olfactory ensheathing cells derived from olfactory bulb and nerve of neonatal and juvenile rats. Neurosci Res 2016; 103:10-7. [DOI: 10.1016/j.neures.2015.07.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 07/24/2015] [Accepted: 07/29/2015] [Indexed: 02/06/2023]
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Sato S, Yajima H, Furuta Y, Ikeda K, Kawakami K. Activation of Six1 Expression in Vertebrate Sensory Neurons. PLoS One 2015; 10:e0136666. [PMID: 26313368 PMCID: PMC4551851 DOI: 10.1371/journal.pone.0136666] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 08/05/2015] [Indexed: 12/31/2022] Open
Abstract
SIX1 homeodomain protein is one of the essential key regulators of sensory organ development. Six1-deficient mice lack the olfactory epithelium, vomeronasal organs, cochlea, vestibule and vestibuloacoustic ganglion, and also show poor neural differentiation in the distal part of the cranial ganglia. Simultaneous loss of both Six1 and Six4 leads to additional abnormalities such as small trigeminal ganglion and abnormal dorsal root ganglia (DRG). The aim of this study was to understand the molecular mechanism that controls Six1 expression in sensory organs, particularly in the trigeminal ganglion and DRG. To this end, we focused on the sensory ganglia-specific Six1 enhancer (Six1-8) conserved between chick and mouse. In vivo reporter assays using both animals identified an important core region comprising binding consensus sequences for several transcription factors including nuclear hormone receptors, TCF/LEF, SMAD, POU homeodomain and basic-helix-loop-helix proteins. The results provided information on upstream factors and signals potentially relevant to Six1 regulation in sensory neurons. We also report the establishment of a new transgenic mouse line (mSix1-8-NLSCre) that expresses Cre recombinase under the control of mouse Six1-8. Cre-mediated recombination was detected specifically in ISL1/2-positive sensory neurons of Six1-positive cranial sensory ganglia and DRG. The unique features of the mSix1-8-NLSCre line are the absence of Cre-mediated recombination in SOX10-positive glial cells and central nervous system and ability to induce recombination in a subset of neurons derived from the olfactory placode/epithelium. This mouse model can be potentially used to advance research on sensory development.
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Affiliation(s)
- Shigeru Sato
- Division of Biology, Center for Molecular Medicine, Jichi Medical University, Shimotsuke, Tochigi, Japan
- * E-mail:
| | - Hiroshi Yajima
- Division of Biology, Center for Molecular Medicine, Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Yasuhide Furuta
- Animal Resource Development Unit and Genetic Engineering Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies (CLST), Kobe, Hyogo, Japan
| | - Keiko Ikeda
- Division of Biology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Kiyoshi Kawakami
- Division of Biology, Center for Molecular Medicine, Jichi Medical University, Shimotsuke, Tochigi, Japan
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30
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Antal MC, Samama B, Ghandour MS, Boehm N. Human Neural Cells Transiently Express Reelin during Olfactory Placode Development. PLoS One 2015; 10:e0135710. [PMID: 26270645 PMCID: PMC4535952 DOI: 10.1371/journal.pone.0135710] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 07/26/2015] [Indexed: 11/18/2022] Open
Abstract
Reelin, an extracellular glycoprotein is essential for migration and correct positioning of neurons during development. Since the olfactory system is known as a source of various migrating neuronal cells, we studied Reelin expression in the two chemosensory olfactory systems, main and accessory, during early developmental stages of human foetuses/embryos from Carnegie Stage (CS) 15 to gestational week (GW) 14. From CS 15 to CS 18, but not at later stages, a transient expression of Reelin was detected first in the presumptive olfactory and then in the presumptive vomeronasal epithelium. During the same period, Reelin-positive cells detach from the olfactory/vomeronasal epithelium and migrate through the mesenchyme beneath the telencephalon. Dab 1, an adaptor protein of the Reelin pathway, was simultaneously expressed in the migratory mass from CS16 to CS17 and, at later stages, in the presumptive olfactory ensheathing cells. Possible involvements of Reelin and Dab 1 in the peripheral migrating stream are discussed.
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Affiliation(s)
- M. Cristina Antal
- Institut d'Histologie, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
- Fédération de Médecine Translationnelle de Strasbourg, Strasbourg, France
- Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- CNRS UMR 7357, Strasbourg, France
| | - Brigitte Samama
- Institut d'Histologie, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
- Fédération de Médecine Translationnelle de Strasbourg, Strasbourg, France
- Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - M. Said Ghandour
- Laboratoire d’Imagerie et de Neurosciences Cognitives, CNRS, UMR 7237, Strasbourg, France
- CNRS UMR 7357, Strasbourg, France
| | - Nelly Boehm
- Institut d'Histologie, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
- Fédération de Médecine Translationnelle de Strasbourg, Strasbourg, France
- Hôpitaux Universitaires de Strasbourg, Strasbourg, France
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31
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Kharlamova AS, Barabanov VM, Saveliev SV. Development of human olfactory bulbs in prenatal ontogenesis: An immunochistochemical study with markers of presynaptic terminals (anti-SNAP-25, synapsin-I, and synaptophysin). Russ J Dev Biol 2015. [DOI: 10.1134/s1062360415030054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Amaya DA, Wegner M, Stolt CC, Chehrehasa F, Ekberg JAK, St John JA. Radial glia phagocytose axonal debris from degenerating overextending axons in the developing olfactory bulb. J Comp Neurol 2015; 523:183-96. [PMID: 25116467 DOI: 10.1002/cne.23665] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 08/06/2014] [Accepted: 08/11/2014] [Indexed: 11/10/2022]
Abstract
Axon targeting during the development of the olfactory system is not always accurate, and numerous axons overextend past the target layer into the deeper layers of the olfactory bulb. To date, the fate of the mis-targeted axons has not been determined. We hypothesized that following overextension, the axons degenerate, and cells within the deeper layers of the olfactory bulb phagocytose the axonal debris. We utilized a line of transgenic mice that expresses ZsGreen fluorescent protein in primary olfactory axons. We found that overextending axons closely followed the filaments of radial glia present in the olfactory bulb during embryonic development. Following overextension into deeper layers of the olfactory bulb, axons degenerated and radial glia responded by phagocytosing the resulting debris. We used in vitro analysis to confirm that the radial glia had phagocytosed debris from olfactory axons. We also investigated whether the fate of overextending axons was altered when the development of the olfactory bulb was perturbed. In mice that lacked Sox10, a transcription factor essential for normal olfactory bulb development, we observed a disruption to the morphology and positioning of radial glia and an accumulation of olfactory axon debris within the bulb. Our results demonstrate that during early development of the olfactory system, radial glia play an important role in removing overextended axons from the deeper layers of the olfactory bulb.
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Affiliation(s)
- Daniel A Amaya
- Eskitis Institute for Drug Discovery, Griffith University, Nathan, Brisbane, Queensland, 4111, Australia
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Odorant receptors signaling instructs the development and plasticity of the glomerular map. Neural Plast 2015; 2015:975367. [PMID: 25688305 PMCID: PMC4320882 DOI: 10.1155/2015/975367] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 12/24/2014] [Accepted: 12/24/2014] [Indexed: 12/21/2022] Open
Abstract
The olfactory system provides a great opportunity to explore the mechanisms that underlie the formation and function of neural circuits because of the simplicity of its structure. Olfactory sensory neurons (OSNs) located in the peripheral olfactory epithelium (OE) take part in the initial formation and function of glomeruli in the olfactory bulb (OB) inside the central nervous system. Glomeruli are key in the process of transduction of olfactory information, as they constitute a map in the OB that sorts the different types of odorant inputs. This odorant categorization allows proper olfactory perception, and it is achieved through the anatomical organization and function of the different glomerular circuits. Once formed, glomeruli keep the capacity to undergo diverse plasticity processes, which is unique among the different neural circuits of the central nervous system. In this context, through the expression and function of the odorant receptors (ORs), OSNs perform two of the most important roles in the olfactory system: transducing odorant information to the nervous system and initiating the development of the glomerular map to organize olfactory information. This review addresses essential information that has emerged in recent years about the molecular basis of these processes.
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34
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Chou RH, Lu CY, Fan JR, Yu YL, Shyu WC. The potential therapeutic applications of olfactory ensheathing cells in regenerative medicine. Cell Transplant 2015; 23:567-71. [PMID: 24816451 DOI: 10.3727/096368914x678508] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Olfactory ensheathing cells (OECs) are unique glia cells restricted to the primary olfactory system including the olfactory mucosa, olfactory nerve, and the outer nerve layer of the olfactory bulb. OECs guide growing olfactory axons from the neurons of the nasal cavity olfactory mucosa to the olfactory bulb to connect both the peripheral nervous system (PNS) and central nervous system (CNS). Based on these specialized abilities of OECs, transplantation of OECs to injury sites has been widely investigated for their potential therapeutic applications in neural repair in different injuries. In this article, we reviewed the properties of OECs and their roles in olfactory regeneration and in treatment of different injuries including spinal cord injury, PNS injury, and stroke and neurodegenerative diseases.
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Affiliation(s)
- Ruey-Hwang Chou
- Graduate Institute of Cancer Biology, Center for Molecular Medicine, China Medical University, Taichung, Taiwan
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Gladwin K, Choi D. Olfactory Ensheathing Cells: Part I—Current Concepts and Experimental Laboratory Models. World Neurosurg 2015; 83:114-9. [DOI: 10.1016/j.wneu.2013.03.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 01/22/2013] [Accepted: 03/08/2013] [Indexed: 10/27/2022]
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Forni PE, Wray S. GnRH, anosmia and hypogonadotropic hypogonadism--where are we? Front Neuroendocrinol 2015; 36:165-77. [PMID: 25306902 PMCID: PMC4703044 DOI: 10.1016/j.yfrne.2014.09.004] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 09/08/2014] [Accepted: 09/25/2014] [Indexed: 11/19/2022]
Abstract
Gonadotropin releasing hormone (GnRH) neurons originate the nasal placode and migrate into the brain during prenatal development. Once within the brain, these cells become integral components of the hypothalamic-pituitary-gonadal axis, essential for reproductive function. Disruption of this system causes hypogonadotropic hypogonadism (HH). HH associated with anosmia is clinically defined as Kallman syndrome (KS). Recent work examining the developing nasal region has shed new light on cellular composition, cell interactions and molecular cues responsible for the development of this system in different species. This review discusses some developmental aspects, animal models and current advancements in our understanding of pathologies affecting GnRH. In addition we discuss how development of neural crest derivatives such as the glia of the olfactory system and craniofacial structures control GnRH development and reproductive function.
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Affiliation(s)
- Paolo E Forni
- Department of Biological Sciences and the Center for Neuroscience Research, University at Albany, State University of New York, Albany, NY 12222, United States.
| | - Susan Wray
- Cellular and Developmental Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, United States.
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Laminar and spatial localization of the islands of Calleja in mice. Neuroscience 2014; 287:137-43. [PMID: 25536047 DOI: 10.1016/j.neuroscience.2014.12.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/04/2014] [Accepted: 12/09/2014] [Indexed: 02/02/2023]
Abstract
The islands of Calleja (IC) are dense clusters of cells localized within the ventral striatum. The IC have been described as variable in both number and localization from animal-to-animal, however, a quantitative investigation of this variability is unavailable. Further, it is presently unknown whether the IC occupy select areas of the olfactory tubercle (OT), the ventral striatum structure which possesses the IC in mice. To address these questions, we examined the IC of adult C57bl/6 mice. As previously noted, we found substantial inter-hemispheric and inter-mouse variations in the total number of IC. While the IC were observed in all three cell layers of the OT, the bulk of IC occupied layer iii. The span of the IC along the anterior-posterior and medial-lateral axes of the OT was variant. Further, localizations of the IC within the OT also differed across animals. Notably, the probability of observing an IC in the medial OT was greater than that of observing one in the lateral. These data provide a fundamental characterization of both differences and similarities regarding the IC in mice and will be informative for future in vivo studies seeking to perturb and possibly record from the IC. Further, we predict that inter-animal diversity in the IC may be a mechanism for inter-animal differences in behavior, especially reward-related and motivational behaviors.
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Chen CR, Kachramanoglou C, Li D, Andrews P, Choi D. Anatomy and cellular constituents of the human olfactory mucosa: a review. J Neurol Surg B Skull Base 2014; 75:293-300. [PMID: 25302141 DOI: 10.1055/s-0033-1361837] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Accepted: 10/07/2013] [Indexed: 02/02/2023] Open
Abstract
Studies using animal models have recently suggested that the olfactory mucosa may be a source of cells capable of stimulating and contributing to complex neurologic regeneration. Several groups have already transplanted cell derivatives from the olfactory mucosa into injury models, and the results so far have been promising. To fully appreciate the meaning of these experiments, a better understanding of the cellular biology and physiology of the olfactory system is necessary. It is therefore of utmost importance for us to first identify and understand its constituents.
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Affiliation(s)
- C Russell Chen
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom
| | - Carolina Kachramanoglou
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom
| | - Daqing Li
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom
| | - Peter Andrews
- Department of ENT, Royal National Throat Nose and Ear Hospital, London, United Kingdom
| | - David Choi
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom
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Transcriptional profiling predicts overwhelming homology of schwann cells, olfactory ensheathing cells, and schwann cell-like glia. Glia 2014; 62:1559-81. [DOI: 10.1002/glia.22700] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 05/15/2014] [Accepted: 05/16/2014] [Indexed: 01/26/2023]
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Kavoi BM, Plendl J, Makanya AN, Ochieng' S, Kiama SG. Effects of anticancer drug docetaxel on the structure and function of the rabbit olfactory mucosa. Tissue Cell 2014; 46:213-24. [PMID: 24846480 DOI: 10.1016/j.tice.2014.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 04/21/2014] [Accepted: 04/22/2014] [Indexed: 11/16/2022]
Abstract
Docetaxel (DCT) is an anticancer drug which acts by disrupting microtubule dynamics in the highly mitotic cancer cells. Thus, this drug has a potential to affect function and organization of tissues exhibiting high cellular turnover. We investigated, in the rabbit, the effects of a single human equivalent dose (6.26 mg/kg, i.v.) of DCT on the olfactory mucosa (OM) through light and electron microscopy, morphometry, Ki-67 immunostaining, TUNEL assay and the buried food test for olfactory sensitivity. On post-exposure days (PED) 5 and 10, there was disarrangement of the normal cell layering in the olfactory epithelium (OE), apoptotic death of cells of the OE, Bowman's glands and axon bundles, and the presence (including on PED 3) of blood vessels in the bundle cores. A decrease in bundle diameters, olfactory cell densities and cilia numbers, which was most significant on PED 10 (49.3%, 63.4% and 50%, respectively), was also evident. Surprisingly by PED 15, the OM regained normal morphology. Furthermore, olfactory sensitivity decreased progressively until PED 10 when olfaction was markedly impaired, and with recovery from the impairment by PED 15. These observations show that DCT transiently alters the structure and function of the OM suggesting a high regenerative potential for this tissue.
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Affiliation(s)
- Boniface M Kavoi
- Department of Veterinary Anatomy and Physiology, Faculty of Veterinary Medicine, University of Nairobi, Riverside Drive, P.O. Box 30197-00100, Nairobi, Kenya.
| | - Johanna Plendl
- Institute of Veterinary Anatomy, Department of Veterinary Medicine, Free University of Berlin, Koserstrasse 20, 14195 Berlin, Germany
| | - Andrew N Makanya
- Department of Veterinary Anatomy and Physiology, Faculty of Veterinary Medicine, University of Nairobi, Riverside Drive, P.O. Box 30197-00100, Nairobi, Kenya; Institute of Anatomy, University of Bern, Balzerstrasse 2, CH-3000 Bern 9, Switzerland
| | - Shem Ochieng'
- International Centre for Insect Physiology and Ecology, P.O. Box 30772, Kasarani, Nairobi, Kenya
| | - Stephen G Kiama
- Department of Veterinary Anatomy and Physiology, Faculty of Veterinary Medicine, University of Nairobi, Riverside Drive, P.O. Box 30197-00100, Nairobi, Kenya
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Quintana-Urzainqui I, Rodríguez-Moldes I, Candal E. Developmental, tract-tracing and immunohistochemical study of the peripheral olfactory system in a basal vertebrate: insights on Pax6 neurons migrating along the olfactory nerve. Brain Struct Funct 2014; 219:85-104. [PMID: 23224251 PMCID: PMC3889696 DOI: 10.1007/s00429-012-0486-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 11/16/2012] [Indexed: 11/02/2022]
Abstract
The olfactory system represents an excellent model for studying different aspects of the development of the nervous system ranging from neurogenesis to mechanisms of axon growth and guidance. Important findings in this field come from comparative studies. We have analyzed key events in the development of the olfactory system of the shark Scyliorhinus canicula by combining immunohistochemical and tract-tracing methods. We describe for the first time in a cartilaginous fish an early population of pioneer HuC/D-immunoreactive (ir) neurons that seemed to delaminate from the olfactory pit epithelium and migrate toward the telencephalon before the olfactory nerve was identifiable. A distinct, transient cell population, namely the migratory mass, courses later on in apposition to the developing olfactory nerve. It contains olfactory ensheathing glial (GFAP-ir) cells and HuC/D-ir neurons, some of which course toward an extrabulbar region. We also demonstrate that Pax6-ir cells coursing along the developing olfactory pathways in S. canicula are young migrating (HuC/D and DCX-ir) neurons of the migratory mass that do not form part of the terminal nerve pathway. Evidences that these Pax6 neurons originate in the olfactory epithelium are also reported. As Pax6 neurons in the olfactory epithelium show characteristics of olfactory receptor neurons, and migrating Pax6-ir neurons formed transient corridors along the course of olfactory axons at the entrance of the olfactory bulb, we propose that these neurons could play a role as guideposts for axons of olfactory receptor neurons growing toward the olfactory bulb.
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Affiliation(s)
- Idoia Quintana-Urzainqui
- Departamento de Biología Celular y Ecología, Edificio CIBUS Campus Vida, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Isabel Rodríguez-Moldes
- Departamento de Biología Celular y Ecología, Edificio CIBUS Campus Vida, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Eva Candal
- Departamento de Biología Celular y Ecología, Edificio CIBUS Campus Vida, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
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Ekberg JAK, St John JA. Crucial roles for olfactory ensheathing cells and olfactory mucosal cells in the repair of damaged neural tracts. Anat Rec (Hoboken) 2013; 297:121-8. [PMID: 24293406 DOI: 10.1002/ar.22803] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 09/13/2013] [Indexed: 11/11/2022]
Abstract
Olfactory ensheathing cells, the glial cells of the olfactory nervous system, exhibit unique growth-promoting and migratory properties that make them interesting candidates for cell therapies targeting neuronal injuries such as spinal cord injury. Transplantation of olfactory cells is feasible and safe in humans; however, functional outcomes are highly variable with some studies showing dramatic improvements and some no improvements at all. We propose that the reason for this is that the identity and purity of the cells is different in each individual study. We have shown that olfactory ensheathing cells are not a uniform cell population and that individual subpopulations of OECs are present in different regions of the olfactory nervous system, with strikingly different behaviors. Furthermore, the presence of fibroblasts and other cell types in the transplant can dramatically alter the behavior of the transplanted glial cells. Thus, a thorough characterization of the differences between olfactory ensheathing cell subpopulations and how the behavior of these cells is affected by the presence of other cell types is highly warranted.
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Affiliation(s)
- Jenny A K Ekberg
- Eskitis Institute for Drug Discovery, Griffith University, Nathan, 4111, Queensland, Australia; School of Biomedical Sciences, Queensland University of Technology, Brisbane, 4000, Queensland, Australia
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Barraud P, St John JA, Stolt CC, Wegner M, Baker CVH. Olfactory ensheathing glia are required for embryonic olfactory axon targeting and the migration of gonadotropin-releasing hormone neurons. Biol Open 2013; 2:750-9. [PMID: 23862023 PMCID: PMC3711043 DOI: 10.1242/bio.20135249] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 05/18/2013] [Indexed: 12/25/2022] Open
Abstract
Kallmann's syndrome is caused by the failure of olfactory axons and gonadotropin-releasing hormone (GnRH) neurons to enter the embryonic forebrain, resulting in anosmia and sterility. Sox10 mutations have been associated with Kallmann's syndrome phenotypes, but their effect on olfactory system development is unknown. We recently showed that Sox10 is expressed by neural crest-derived olfactory ensheathing cells (OECs). Here, we demonstrate that in homozygous Sox10(lacZ/lacZ) mouse embryos, OEC differentiation is disrupted; olfactory axons accumulate in the ventromedial olfactory nerve layer and fewer olfactory receptor neurons express the maturation marker OMP (most likely owing to the failure of axonal targeting). Furthermore, GnRH neurons clump together in the periphery and a smaller proportion enters the forebrain. Our data suggest that human Sox10 mutations cause Kallmann's syndrome by disrupting the differentiation of OECs, which promote embryonic olfactory axon targeting and hence olfactory receptor neuron maturation, and GnRH neuron migration to the forebrain.
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Affiliation(s)
- Perrine Barraud
- Department of Physiology, Development and Neuroscience, University of Cambridge , Cambridge CB2 3DY , UK
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Rawji KS, Zhang SX, Tsai YY, Smithson LJ, Kawaja MD. Olfactory ensheathing cells of hamsters, rabbits, monkeys, and mice express α-smooth muscle actin. Brain Res 2013; 1521:31-50. [PMID: 23665391 DOI: 10.1016/j.brainres.2013.05.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 04/30/2013] [Accepted: 05/02/2013] [Indexed: 10/26/2022]
Abstract
Olfactory ensheathing cells (OECs) are the chief glial population of the mammalian olfactory nervous system, residing in the olfactory mucosa and at the surface of the olfactory bulb. We investigated the neurochemical features of OECs in a variety of mammalian species (including adult hamsters, rabbits, monkeys, and mice, as well as fetal pigs) using three biomarkers: α-smooth muscle actin (αSMA), S100β, and glial fibrillary acidic protein (GFAP). Mucosal and bulbar OECs from all five mammalian species express S100β. Both mucosal and bulbar OECs of monkeys express αSMA, yet only bulbar OECs of hamsters and only mucosal OECs of rabbits express αSMA as well. Mucosal OECs, but not bulbar OECs, also express GFAP in hamsters and monkeys; mice, by comparison, have only a sparse population of OECs expressing GFAP. Though αSMA immunostaining is not detected in OECs of adult mice, GFAP-expressing mucosal OECs isolated from adult mice do coexpress αSMA in vitro. Moreover, mucosal OECs from adult mutant mice lacking αSMA expression display perturbed cellular morphology (i.e., fewer cytoplasmic processes extending among the hundreds of olfactory axons in the olfactory nerve fascicles and nuclei having degenerative features). In sum, these findings highlight the efficacy of αSMA and S100β as biomarkers of OECs from a variety of mammalian species. These observations provide definitive evidence that mammalian OECs express the structural protein αSMA (at various levels of detection), which appears to play a pivotal role in their ensheathment of olfactory axons.
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Affiliation(s)
- Khalil S Rawji
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada K7L 3N6
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Geller S, Kolasa E, Tillet Y, Duittoz A, Vaudin P. Olfactory ensheathing cells form the microenvironment of migrating GnRH-1 neurons during mouse development. Glia 2013; 61:550-66. [PMID: 23404564 DOI: 10.1002/glia.22455] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 11/28/2012] [Indexed: 11/08/2022]
Abstract
During development, GnRH-1 neurons differentiate extracerebraly from the nasal placode and migrate from the vomeronasal organ to the forebrain along vomeronasal and terminal nerves. Numerous studies have described the influence of different molecules on the migration of GnRH-1 neurons, however, the role of microenvironment cells remains poorly understood. This study used GFAP-GFP transgenic mice to detect glial cells at early developmental stages. Using nasal explant cultures, the comigration of glial cells with GnRH-1 neurons was clearly demonstrated. This in vitro approach showed that glial cells began migrating from the explants before GnRH-1 neurons. They remained ahead of the GnRH-1 migratory front and stopped migrating after the GnRH-1 neurons. The association of these glial cells with the axons combined with gene expression analysis of GFAP-GFP sorted cells enabled them to be identified as olfactory ensheathing cells (OEC). Immunohistochemical analysis revealed the presence of multiple glial cell-type markers showing several OEC subpopulations surrounding GnRH-1 neurons. Moreover, these OEC expressed genes whose products are involved in the migration of GnRH-1 neurons, such as Nelf and Semaphorin 4. In situ data confirmed that the majority of the GnRH-1 neurons were associated with glial cells along the vomeronasal axons in nasal septum and terminal nerves in the nasal forebrain junction as early as E12.5. Overall, these data demonstrate an OEC microenvironment for migrating GnRH-1 neurons during mouse development. The fact that this glial cell type precedes GnRH-1 neurons and encodes for molecules involved in their nasal migration suggests that it participates in the GnRH-1 system ontogenesis.
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Affiliation(s)
- Sarah Geller
- Physiologie de la Reproduction et des Comportements, UMR 0085 INRA, 6175 CNRS, Université François Rabelais de Tours, IFCE, IFR135 Imagerie Fonctionnelle 37380, Nouzilly, France
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Morphological phenotypes of olfactory ensheathing cells display different migratory responses upon Slit-2. Exp Cell Res 2012; 318:1889-900. [DOI: 10.1016/j.yexcr.2012.05.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 05/11/2012] [Accepted: 05/24/2012] [Indexed: 11/18/2022]
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Shaker T, Dennis D, Kurrasch DM, Schuurmans C. Neurog1 and Neurog2 coordinately regulate development of the olfactory system. Neural Dev 2012; 7:28. [PMID: 22906231 PMCID: PMC3444899 DOI: 10.1186/1749-8104-7-28] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 08/03/2012] [Indexed: 01/23/2023] Open
Abstract
Background Proneural genes encode basic helix–loop–helix transcription factors that specify distinct neuronal identities in different regions of the nervous system. In the embryonic telencephalon, the proneural genes Neurog1 and Neurog2 specify a dorsal regional identity and glutamatergic projection neuron phenotype in the presumptive neocortex, but their roles in cell fate specification in the olfactory bulb, which is also partly derived from dorsal telencephalic progenitors, have yet to be assessed. Given that olfactory bulb development is guided by interactions with the olfactory epithelium in the periphery, where proneural genes are also expressed, we investigated the roles of Neurog1 and Neurog2 in the coordinated development of these two olfactory structures. Results Neurog1/2 are co-expressed in olfactory bulb progenitors, while only Neurog1 is widely expressed in progenitors for olfactory sensory neurons in the olfactory epithelium. Strikingly, only a remnant of an olfactory bulb forms in Neurog1−/−;Neurog2−/− double mutants, while this structure is smaller but distinguishable in Neurog1−/− single mutants and morphologically normal in Neurog2−/− single mutants. At the cellular level, fewer glutamatergic mitral and juxtaglomerular cells differentiate in Neurog1−/−;Neurog2−/− double-mutant olfactory bulbs. Instead, ectopic olfactory bulb interneurons are derived from dorsal telencephalic lineages in Neurog1−/−;Neurog2−/− double mutants and to a lesser extent in Neurog2−/− single mutants. Conversely, cell fate specification is normal in Neurog1−/− olfactory bulbs, but aberrant patterns of cell proliferation and neuronal migration are observed in Neurog1−/− single and Neurog1−/−;Neurog2−/− double mutants, probably contributing to their altered morphologies. Finally, in Neurog1−/− and Neurog1−/−;Neurog2−/− embryos, olfactory sensory neurons in the epithelium, which normally project to the olfactory bulb to guide its morphogenesis, fail to innervate the olfactory bulb. Conclusions We have identified a cell autonomous role for Neurog1/2 in specifying the glutamatergic identity of olfactory bulb neurons. Furthermore, Neurog1 (and not Neurog2) is required to guide olfactory sensory neuron innervation of the olfactory bulb, the loss of which results in defects in olfactory bulb proliferation and tissue morphogenesis. We thus conclude that Neurog1/2 together coordinate development of the olfactory system, which depends on tissue interactions between the olfactory bulb and epithelium.
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Affiliation(s)
- Tarek Shaker
- Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Health Sciences Centre, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
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Ferreiro-Galve S, Candal E, Rodríguez-Moldes I. Dynamic expression of Pax6 in the shark olfactory system: evidence for the presence of Pax6 cells along the olfactory nerve pathway. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2012; 318:79-90. [PMID: 22532471 DOI: 10.1002/jezb.21444] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Pax6 is involved in the control of neuronal specification, migration, and differentiation in the olfactory epithelium and in the generation of different interneuron subtypes in the olfactory bulb. Whether these roles are conserved during evolution is not known. Cartilaginous fish are extremely useful models for assessing the ancestral condition of brain organization because of their phylogenetic position. To shed light on the evolution of development of the olfactory system in vertebrates and on the involvement of Pax6 in this process, we analyzed by in situ hybridization and immunohistochemistry the expression pattern of Pax6 in the developing olfactory system in a basal vertebrate, the lesser spotted dogfish Scyliorhinus canicula. This small shark is becoming an important fish model in studies of vertebrate development. We report Pax6 expression in cells of the olfactory epithelium and olfactory bulb, and present the first evidence in vertebrates of strings of Pax6-expressing cells extending along the developing olfactory nerve. The results indicate the olfactory epithelium as the origin of these cells. These data are compatible with a role for Pax6 in the development of the olfactory epithelium and fibers, and provide a basis for future investigations into the mechanisms that regulate development of the olfactory system throughout evolution.
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Affiliation(s)
- Susana Ferreiro-Galve
- Department of Cell Biology and Ecology, University of Santiago de Compostela, Compostela, Spain
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Ekberg JAK, Amaya D, Mackay-Sim A, St John JA. The migration of olfactory ensheathing cells during development and regeneration. Neurosignals 2012; 20:147-58. [PMID: 22456085 DOI: 10.1159/000330895] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Accepted: 07/20/2011] [Indexed: 11/19/2022] Open
Abstract
The primary olfactory nervous system is unique in that it continuously renews itself and regenerates after injury. These properties are attributed to the presence of olfactory glia, termed olfactory ensheathing cells (OECs). Evidence is now emerging that individual OEC populations exist with distinct anatomical localisations and physiological properties, but their differential roles have not been determined. Unlike other glia, OECs can migrate from the periphery into the central nervous system, and organised OEC migration can enhance axonal extension after injury. Despite this, the mechanisms regulating OEC migration are largely unknown. Here, we provide an overview of the roles of OECs in development and adulthood. We review the latest research describing the differences between individual OEC subpopulations and discuss potential regulatory mechanisms for OEC guidance and migration. Using advanced time lapse techniques, we have obtained novel insights into how OECs behave in a complex multicellular environment which we discuss here with particular focus on cell-cell interactions. Significantly, transplantation of OECs constitutes a promising novel therapy for nerve injuries, but results are highly variable and the method needs improvement. We here review the roles of transplanted OECs in neural repair of damaged neuronal tracts distinct from the primary olfactory nervous system.
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Affiliation(s)
- Jenny A K Ekberg
- Eskitis Institute for Cell and Molecular Therapies, Griffith University, Brisbane, Qld, Australia
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