1
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Andrews G, Andrews G, Leung YF, Suter DM. A robust paradigm for studying regeneration after traumatic spinal cord injury in zebrafish. J Neurosci Methods 2024; 410:110243. [PMID: 39117153 DOI: 10.1016/j.jneumeth.2024.110243] [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: 02/16/2024] [Revised: 08/01/2024] [Accepted: 08/05/2024] [Indexed: 08/10/2024]
Abstract
BACKGROUND Zebrafish are vertebrates with a high potential of regeneration after injury in the central nervous system. Therefore, they have emerged as a useful model system for studying traumatic spinal cord injuries. NEW METHOD Using larval zebrafish, we have developed a robust paradigm to model the effects of anterior spinal cord injury, which correspond to the debilitating injuries of the cervical and thoracic regions in humans. Our new paradigm consists of a more anterior injury location compared to previous studies, a modified behavioral assessment using the visual motor response, and a new data analysis code. RESULTS Our approach enables a spinal cord injury closer to the hindbrain with more functional impact compared to previous studies using a more posterior injury location. Results reported in this work reveal recovery over seven days following spinal cord injury. COMPARING WITH EXISTING METHODS The present work describes a modified paradigm for the in vivo study of spinal cord regeneration after injury using larval zebrafish, including an anterior injury location, a robust behavioral assessment, and a new data analysis software. CONCLUSIONS Our findings lay the foundation for applying this paradigm to study the effects of drugs, nutrition, and other treatments to improve the regeneration process.
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Affiliation(s)
- Gentry Andrews
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Geoffrey Andrews
- School of Aeronautics and Astronautics, Purdue University, West Lafayette, IN 47907, USA
| | - Yuk Fai Leung
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Drug Discovery, Purdue University, West Lafayette, IN 47907, USA
| | - Daniel M Suter
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA; Institute for Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA; Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907, USA; Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907, USA; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA.
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2
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Jiang Y, Cai Y, Yang N, Gao S, Li Q, Pang Y, Su P. Molecular mechanisms of spinal cord injury repair across vertebrates: A comparative review. Eur J Neurosci 2024. [PMID: 38978308 DOI: 10.1111/ejn.16462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 05/09/2024] [Accepted: 06/20/2024] [Indexed: 07/10/2024]
Abstract
In humans and other adult mammals, axon regeneration is difficult in axotomized neurons. Therefore, spinal cord injury (SCI) is a devastating event that can lead to permanent loss of locomotor and sensory functions. Moreover, the molecular mechanisms of axon regeneration in vertebrates are not very well understood, and currently, no effective treatment is available for SCI. In striking contrast to adult mammals, many nonmammalian vertebrates such as reptiles, amphibians, bony fishes and lampreys can spontaneously resume locomotion even after complete SCI. In recent years, rapid progress in the development of next-generation sequencing technologies has offered valuable information on SCI. In this review, we aimed to provide a comparison of axon regeneration process across classical model organisms, focusing on crucial genes and signalling pathways that play significant roles in the regeneration of individually identifiable descending neurons after SCI. Considering the special evolutionary location and powerful regenerative ability of lamprey and zebrafish, they will be the key model organisms for ongoing studies on spinal cord regeneration. Detailed study of SCI in these model organisms will help in the elucidation of molecular mechanisms of neuron regeneration across species.
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Affiliation(s)
- Ying Jiang
- College of Life Science, Liaoning Normal University, Dalian, China
- Lamprey Research Center, Liaoning Normal University, Dalian, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Yang Cai
- College of Life Science, Liaoning Normal University, Dalian, China
- Lamprey Research Center, Liaoning Normal University, Dalian, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Ning Yang
- College of Life Science, Liaoning Normal University, Dalian, China
- Lamprey Research Center, Liaoning Normal University, Dalian, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Si Gao
- College of Life Science, Liaoning Normal University, Dalian, China
- Lamprey Research Center, Liaoning Normal University, Dalian, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Qingwei Li
- College of Life Science, Liaoning Normal University, Dalian, China
- Lamprey Research Center, Liaoning Normal University, Dalian, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Yue Pang
- College of Life Science, Liaoning Normal University, Dalian, China
- Lamprey Research Center, Liaoning Normal University, Dalian, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Peng Su
- College of Life Science, Liaoning Normal University, Dalian, China
- Lamprey Research Center, Liaoning Normal University, Dalian, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
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3
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Stefanova EE, Dychiao JVT, Chinn MC, Borhani M, Scott AL. P2X7 regulates ependymo-radial glial cell proliferation in adult Danio rerio following spinal cord injury. Biol Open 2024; 13:bio060270. [PMID: 38526172 PMCID: PMC11033521 DOI: 10.1242/bio.060270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 03/11/2024] [Indexed: 03/26/2024] Open
Abstract
In contrast to mammals, zebrafish undergo successful neural regeneration following spinal cord injury. Spinal cord ependymo-radial glia (ERG) undergo injury-induced proliferation and neuronal differentiation to replace damaged cells and restore motor function. However, the molecular cues driving these processes remain elusive. Here, we demonstrate that the evolutionarily conserved P2X7 receptors are widely distributed on neurons and ERG within the zebrafish spinal cord. At the protein level, the P2X7 receptor expressed in zebrafish is a truncated splice variant of the full-length variant found in mammals. The protein expression of this 50 kDa isoform was significantly downregulated at 7 days post-injury (dpi) but returned to basal levels at 14 dpi when compared to naïve controls. Pharmacological activation of P2X7 following SCI resulted in a greater number of proliferating cells around the central canal by 7 dpi but did not affect neuronal differentiation at 14 dpi. Our findings suggest that unlike in mammals, P2X7 signaling may not play a maladaptive role following SCI in adult zebrafish and may also work to curb the proliferative response of ERG following injury.
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Affiliation(s)
- Eva E. Stefanova
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | | | - Mavis C. Chinn
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Matin Borhani
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Angela L. Scott
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
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4
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Pushchina EV, Kapustyanov IA, Kluka GG. Adult Neurogenesis of Teleost Fish Determines High Neuronal Plasticity and Regeneration. Int J Mol Sci 2024; 25:3658. [PMID: 38612470 PMCID: PMC11012045 DOI: 10.3390/ijms25073658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 02/28/2024] [Accepted: 03/07/2024] [Indexed: 04/14/2024] Open
Abstract
Studying the properties of neural stem progenitor cells (NSPCs) in a fish model will provide new information about the organization of neurogenic niches containing embryonic and adult neural stem cells, reflecting their development, origin cell lines and proliferative dynamics. Currently, the molecular signatures of these populations in homeostasis and repair in the vertebrate forebrain are being intensively studied. Outside the telencephalon, the regenerative plasticity of NSPCs and their biological significance have not yet been practically studied. The impressive capacity of juvenile salmon to regenerate brain suggests that most NSPCs are likely multipotent, as they are capable of replacing virtually all cell lineages lost during injury, including neuroepithelial cells, radial glia, oligodendrocytes, and neurons. However, the unique regenerative profile of individual cell phenotypes in the diverse niches of brain stem cells remains unclear. Various types of neuronal precursors, as previously shown, are contained in sufficient numbers in different parts of the brain in juvenile Pacific salmon. This review article aims to provide an update on NSPCs in the brain of common models of zebrafish and other fish species, including Pacific salmon, and the involvement of these cells in homeostatic brain growth as well as reparative processes during the postraumatic period. Additionally, new data are presented on the participation of astrocytic glia in the functioning of neural circuits and animal behavior. Thus, from a molecular aspect, zebrafish radial glia cells are seen to be similar to mammalian astrocytes, and can therefore also be referred to as astroglia. However, a question exists as to if zebrafish astroglia cells interact functionally with neurons, in a similar way to their mammalian counterparts. Future studies of this fish will complement those on rodents and provide important information about the cellular and physiological processes underlying astroglial function that modulate neural activity and behavior in animals.
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Affiliation(s)
- Evgeniya Vladislavovna Pushchina
- A.V. Zhirmunsky National Scientific Center of Marine Biology, Far East Branch, Russian Academy of Sciences, 690041 Vladivostok, Russia; (I.A.K.); (G.G.K.)
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5
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Crossman SH, Khabooshan MA, Stamatis SA, Vandestadt C, Kaslin J. Mechanical Ablation of Larval Zebrafish Spinal Cord. Methods Mol Biol 2024; 2746:47-56. [PMID: 38070078 DOI: 10.1007/978-1-0716-3585-8_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Unlike mammals, adult and larval zebrafish exhibit robust regeneration following traumatic spinal cord injury. This remarkable regenerative capacity, combined with exquisite imaging capabilities and an abundance of powerful genetic techniques, has established the zebrafish as an important vertebrate model for the study of neural regeneration. Here, we describe a protocol for the complete mechanical ablation of the larval zebrafish spinal cord. With practice, this protocol can be used to reproducibly injure upward of 100 samples per hour, facilitating the high-throughput screening of factors involved in spinal cord regeneration and repair.
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Affiliation(s)
- Samuel Henry Crossman
- The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia.
| | - Mitra Amiri Khabooshan
- The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia
| | | | - Celia Vandestadt
- The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia
| | - Jan Kaslin
- The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia.
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6
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Becker CJ, Cigliola V, Gillotay P, Rich A, De Simone A, Han Y, Di Talia S, Poss KD. In toto imaging of glial JNK signaling during larval zebrafish spinal cord regeneration. Development 2023; 150:dev202076. [PMID: 37997694 PMCID: PMC10753585 DOI: 10.1242/dev.202076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 11/09/2023] [Indexed: 11/25/2023]
Abstract
Identification of signaling events that contribute to innate spinal cord regeneration in zebrafish can uncover new targets for modulating injury responses of the mammalian central nervous system. Using a chemical screen, we identify JNK signaling as a necessary regulator of glial cell cycling and tissue bridging during spinal cord regeneration in larval zebrafish. With a kinase translocation reporter, we visualize and quantify JNK signaling dynamics at single-cell resolution in glial cell populations in developing larvae and during injury-induced regeneration. Glial JNK signaling is patterned in time and space during development and regeneration, decreasing globally as the tissue matures and increasing in the rostral cord stump upon transection injury. Thus, dynamic and regional regulation of JNK signaling help to direct glial cell behaviors during innate spinal cord regeneration.
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Affiliation(s)
- Clayton J. Becker
- Duke Regeneration Center and Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Valentina Cigliola
- Duke Regeneration Center and Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
- Université Côte d’Azur, Inserm, CNRS, Institut de Biologie Valrose, 06100 Nice, France
| | - Pierre Gillotay
- Duke Regeneration Center and Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ashley Rich
- Duke Regeneration Center and Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Alessandro De Simone
- Department of Genetics and Evolution, University of Geneva, 1211 Geneva, Switzerland
| | - Yanchao Han
- Department of Cardiovascular Surgery of the First Affiliated Hospital & Institute for Cardiovascular Science, Suzhou Medical College, Soochow University, Suzhou, 215006 Jiangsu, China
| | - Stefano Di Talia
- Duke Regeneration Center and Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Kenneth D. Poss
- Duke Regeneration Center and Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
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7
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Cigliola V, Shoffner A, Lee N, Ou J, Gonzalez TJ, Hoque J, Becker CJ, Han Y, Shen G, Faw TD, Abd-El-Barr MM, Varghese S, Asokan A, Poss KD. Spinal cord repair is modulated by the neurogenic factor Hb-egf under direction of a regeneration-associated enhancer. Nat Commun 2023; 14:4857. [PMID: 37567873 PMCID: PMC10421883 DOI: 10.1038/s41467-023-40486-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 07/26/2023] [Indexed: 08/13/2023] Open
Abstract
Unlike adult mammals, zebrafish regenerate spinal cord tissue and recover locomotor ability after a paralyzing injury. Here, we find that ependymal cells in zebrafish spinal cords produce the neurogenic factor Hb-egfa upon transection injury. Animals with hb-egfa mutations display defective swim capacity, axon crossing, and tissue bridging after spinal cord transection, associated with disrupted indicators of neuron production. Local recombinant human HB-EGF delivery alters ependymal cell cycling and tissue bridging, enhancing functional regeneration. Epigenetic profiling reveals a tissue regeneration enhancer element (TREE) linked to hb-egfa that directs gene expression in spinal cord injuries. Systemically delivered recombinant AAVs containing this zebrafish TREE target gene expression to crush injuries of neonatal, but not adult, murine spinal cords. Moreover, enhancer-based HB-EGF delivery by AAV administration improves axon densities after crush injury in neonatal cords. Our results identify Hb-egf as a neurogenic factor necessary for innate spinal cord regeneration and suggest strategies to improve spinal cord repair in mammals.
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Affiliation(s)
- Valentina Cigliola
- Duke Regeneration Center, Duke University, Durham, NC, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
- Université Côte d'Azur, Inserm, CNRS, Institut de Biologie Valrose, Nice, France
| | - Adam Shoffner
- Duke Regeneration Center, Duke University, Durham, NC, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
| | - Nutishia Lee
- Duke Regeneration Center, Duke University, Durham, NC, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
| | - Jianhong Ou
- Duke Regeneration Center, Duke University, Durham, NC, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
| | - Trevor J Gonzalez
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA
| | - Jiaul Hoque
- Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA
| | - Clayton J Becker
- Duke Regeneration Center, Duke University, Durham, NC, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
| | - Yanchao Han
- Department of Cardiovascular Surgery of the First Affiliated Hospital and Institute for Cardiovascular Science, Soochow University, Suzhou, Jiangsu, China
| | - Grace Shen
- Duke Regeneration Center, Duke University, Durham, NC, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
| | - Timothy D Faw
- Duke Regeneration Center, Duke University, Durham, NC, USA
- Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA
- Duke Institute for Brain Sciences, Duke University, Durham, NC, USA
| | | | - Shyni Varghese
- Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Aravind Asokan
- Duke Regeneration Center, Duke University, Durham, NC, USA
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Kenneth D Poss
- Duke Regeneration Center, Duke University, Durham, NC, USA.
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.
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8
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Zhao Y, Wang H, He T, Ma B, Chen G, Tzeng C. Knockdown of Yap attenuates TAA-induced hepatic fibrosis by interaction with hedgehog signals. J Cell Commun Signal 2023:10.1007/s12079-023-00775-6. [PMID: 37338798 DOI: 10.1007/s12079-023-00775-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 06/05/2023] [Indexed: 06/21/2023] Open
Abstract
Liver fibrosis is an aberrant wound healing response to tissue injury characterized by excessive extracellular matrix deposition and loss of normal liver architecture. Hepatic stellate cells (HSCs) activation is regards to be the major process in liver fibrogenesis which is dynamic and reversible. Both Hippo signaling core factor Yap and Hedgehog (Hh) signaling promote HSCs transdifferentiation thereby regulating the repair process of liver injury. However, the molecular function of YAP and the regulation between Yap and Hh during fibrogenesis remain uncertain. In this study, the essential roles of Yap in liver fibrosis were investigated. Yap was detected to be increased in liver fibrotic tissue by the thioacetamide (TAA)-induced zebrafish embryonic and adult models. Inhibition of Yap by both embryonic morpholino interference and adult's inhibitor treatment was proved to alleviate TAA-induced liver lesions by and histology and gene expression examination. Transcriptomic analysis and gene expression detection showed that Yap and Hh signaling pathway have a cross talking upon TAA-induced liver fibrosis. In addition, TAA induction promoted the nuclear colocalization of YAP and Hh signaling factor GLI2α. This study demonstrates that Yap and Hh play synergistic protective roles in liver fibrotic response and provides new theoretical insight concerning the mechanisms of fibrosis progression.
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Affiliation(s)
- Ye Zhao
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, 211800, China.
| | - Huiling Wang
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, 211800, China
| | - Tianhua He
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, 211800, China
| | - Bo Ma
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, 211800, China
| | - Guoguang Chen
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, 211800, China
| | - Chimeng Tzeng
- School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361005, China.
- Translational Medicine Research Center-Key Laboratory for Cancer T-Cell Theragnostic and Clinical Translation, School of Pharmaceutical Sciences, Xiamen University, Xiamen, Fujian, China.
- Xiamen Chang Gung Hospital Medical Research Center, Xiamen, Fujian, China.
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9
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Saraswathy VM, Zhou L, Mokalled MH. Single-cell analysis of innate spinal cord regeneration identifies intersecting modes of neuronal repair. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.19.541505. [PMID: 37292638 PMCID: PMC10245778 DOI: 10.1101/2023.05.19.541505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Adult zebrafish have an innate ability to recover from severe spinal cord injury. Here, we report a comprehensive single nuclear RNA sequencing atlas that spans 6 weeks of regeneration. We identify cooperative roles for adult neurogenesis and neuronal plasticity during spinal cord repair. Neurogenesis of glutamatergic and GABAergic neurons restores the excitatory/inhibitory balance after injury. In addition, transient populations of injury-responsive neurons (iNeurons) show elevated plasticity between 1 and 3 weeks post-injury. Using cross-species transcriptomics and CRISPR/Cas9 mutagenesis, we found iNeurons are injury-surviving neurons that share transcriptional similarities with a rare population of spontaneously plastic mouse neurons. iNeurons are required for functional recovery and employ vesicular trafficking as an essential mechanism that underlies neuronal plasticity. This study provides a comprehensive resource of the cells and mechanisms that direct spinal cord regeneration and establishes zebrafish as a model of plasticity-driven neural repair.
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10
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Underwood KL, Walker WJ, Garrett PI, Linch S, Rynes TP, Mruk K. Optimizing spinal cord injury in zebrafish larvae: effects of age on the injury response. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.18.541337. [PMID: 37292959 PMCID: PMC10245662 DOI: 10.1101/2023.05.18.541337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Zebrafish are an increasingly popular model to study spinal cord injury (SCI) regeneration. The transparency of larval zebrafish makes them ideal to study cellular processes in real time. Standardized approaches, including age of injury, are not readily available making comparisons of the results with other models challenging. In this study, we systematically examined the response to spinal cord transection of larval zebrafish at three different ages (3-7 days post fertilization or dpf) to determine whether the developmental complexity of the central nervous system affects the overall response to SCI. We then used imaging and behavioral analysis to evaluate whether differences existed based on the age of injury. All ages of larval zebrafish upregulated the required genes for glial bridge formation, ctgfa and gfap, at the site of injury, consistent with studies from adult zebrafish. Though all larval ages upregulated factors required to promote glial bridging, young larval zebrafish (3 dpf) were better able to regenerate axons independent of the glial bridge, unlike older zebrafish (7 dpf). Consistent with this data, locomotor experiments demonstrated that some swimming behavior occurs independent of glial bridge formation, further highlighting the need for standardization of this model and recovery assays. Overall, we found subtle cellular differences based on the age of transection in zebrafish, underlining the importance of considering age when designing experiments aimed at understanding regeneration.
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11
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Saraswathy VM, Zhou L, McAdow AR, Burris B, Dogra D, Reischauer S, Mokalled MH. Myostatin is a negative regulator of adult neurogenesis after spinal cord injury in zebrafish. Cell Rep 2022; 41:111705. [PMID: 36417881 PMCID: PMC9742758 DOI: 10.1016/j.celrep.2022.111705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 05/16/2022] [Accepted: 11/01/2022] [Indexed: 11/23/2022] Open
Abstract
Intrinsic and extrinsic inhibition of neuronal regeneration obstruct spinal cord (SC) repair in mammals. In contrast, adult zebrafish achieve functional recovery after complete SC transection. While studies of innate SC regeneration have focused on axon regrowth as a primary repair mechanism, how local adult neurogenesis affects functional recovery is unknown. Here, we uncover dynamic expression of zebrafish myostatin b (mstnb) in a niche of dorsal SC progenitors after injury. mstnb mutants show impaired functional recovery, normal glial and axonal bridging across the lesion, and an increase in the profiles of newborn neurons. Molecularly, neuron differentiation genes are upregulated, while the neural stem cell maintenance gene fgf1b is downregulated in mstnb mutants. Finally, we show that human fibroblast growth factor 1 (FGF1) treatment rescues the molecular and cellular phenotypes of mstnb mutants. These studies uncover unanticipated neurogenic functions for mstnb and establish the importance of local adult neurogenesis for innate SC repair.
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Affiliation(s)
- Vishnu Muraleedharan Saraswathy
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Lili Zhou
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Anthony R McAdow
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Brooke Burris
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Deepika Dogra
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany; Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Sven Reischauer
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany; Medical Clinic I, (Cardiology/Angiology) and Campus Kerckhoff, Justus Liebig University, Giessen, 35392 Giessen, Germany; The Cardio-Pulmonary Institute, Frankfurt, Germany
| | - Mayssa H Mokalled
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA.
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12
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Alper SR, Dorsky RI. Unique advantages of zebrafish larvae as a model for spinal cord regeneration. Front Mol Neurosci 2022; 15:983336. [PMID: 36157068 PMCID: PMC9489991 DOI: 10.3389/fnmol.2022.983336] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/18/2022] [Indexed: 11/30/2022] Open
Abstract
The regenerative capacity of the spinal cord in mammals ends at birth. In contrast, teleost fish and amphibians retain this capacity throughout life, leading to the use of the powerful zebrafish model system to identify novel mechanisms that promote spinal cord regeneration. While adult zebrafish offer an effective comparison with non-regenerating mammals, they lack the complete array of experimental approaches that have made this animal model so successful. In contrast, the optical transparency, simple anatomy and complex behavior of zebrafish larvae, combined with the known conservation of pro-regenerative signals and cell types between larval and adult stages, suggest that they may hold even more promise as a system for investigating spinal cord regeneration. In this review, we highlight characteristics and advantages of the larval model that underlie its potential to provide future therapeutic approaches for treating human spinal cord injury.
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13
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Caron A, Trzuskot L, Lindsey BW. Uncovering the spectrum of adult zebrafish neural stem cell cycle regulators. Front Cell Dev Biol 2022; 10:941893. [PMID: 35846369 PMCID: PMC9277145 DOI: 10.3389/fcell.2022.941893] [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: 05/11/2022] [Accepted: 06/16/2022] [Indexed: 11/13/2022] Open
Abstract
Adult neural stem and progenitor cells (aNSPCs) persist lifelong in teleost models in diverse stem cell niches of the brain and spinal cord. Fish maintain developmental stem cell populations throughout life, including both neuro-epithelial cells (NECs) and radial-glial cells (RGCs). Within stem cell domains of the brain, RGCs persist in a cycling or quiescent state, whereas NECs continuously divide. Heterogeneous populations of RGCs also sit adjacent the central canal of the spinal cord, showing infrequent proliferative activity under homeostasis. With the rise of the zebrafish (Danio rerio) model to study adult neurogenesis and neuroregeneration in the central nervous system (CNS), it has become evident that aNSPC proliferation is regulated by a wealth of stimuli that may be coupled with biological function. Growing evidence suggests that aNSPCs are sensitive to environmental cues, social interactions, nutrient availability, and neurotrauma for example, and that distinct stem and progenitor cell populations alter their cell cycle activity accordingly. Such stimuli appear to act as triggers to either turn on normally dormant aNSPCs or modulate constitutive rates of niche-specific cell cycle behaviour. Defining the various forms of stimuli that influence RGC and NEC proliferation, and identifying the molecular regulators responsible, will strengthen our understanding of the connection between aNSPC activity and their biological significance. In this review, we aim to bring together the current state of knowledge on aNSPCs from studies investigating the zebrafish CNS, while highlighting emerging cell cycle regulators and outstanding questions that will help to advance this fascinating field of stem cell biology.
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Affiliation(s)
- Aurélien Caron
- Laboratory of Neural Stem Cell Plasticity and Regeneration, Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Lidia Trzuskot
- Laboratory of Neural Stem Cell Plasticity and Regeneration, Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Benjamin W Lindsey
- Laboratory of Neural Stem Cell Plasticity and Regeneration, Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
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14
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Becker T, Becker CG. Regenerative neurogenesis: the integration of developmental, physiological and immune signals. Development 2022; 149:275248. [PMID: 35502778 PMCID: PMC9124576 DOI: 10.1242/dev.199907] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In fishes and salamanders, but not mammals, neural stem cells switch back to neurogenesis after injury. The signalling environment of neural stem cells is strongly altered by the presence of damaged cells and an influx of immune, as well as other, cells. Here, we summarise our recently expanded knowledge of developmental, physiological and immune signals that act on neural stem cells in the zebrafish central nervous system to directly, or indirectly, influence their neurogenic state. These signals act on several intracellular pathways, which leads to changes in chromatin accessibility and gene expression, ultimately resulting in regenerative neurogenesis. Translational approaches in non-regenerating mammals indicate that central nervous system stem cells can be reprogrammed for neurogenesis. Understanding signalling mechanisms in naturally regenerating species show the path to experimentally promoting neurogenesis in mammals.
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Affiliation(s)
- Thomas Becker
- Center for Regenerative Therapies at the TU Dresden, Technische Universität Dresden, 01307 Dresden, Germany.,Centre for Discovery Brain Sciences, University of Edinburgh Medical School, Biomedical Science, Edinburgh, EH16 4SB, Scotland
| | - Catherina G Becker
- Center for Regenerative Therapies at the TU Dresden, Technische Universität Dresden, 01307 Dresden, Germany.,Centre for Discovery Brain Sciences, University of Edinburgh Medical School, Biomedical Science, Edinburgh, EH16 4SB, Scotland
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15
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Sanchez-Gonzalez R, Koupourtidou C, Lepko T, Zambusi A, Novoselc KT, Durovic T, Aschenbroich S, Schwarz V, Breunig CT, Straka H, Huttner HB, Irmler M, Beckers J, Wurst W, Zwergal A, Schauer T, Straub T, Czopka T, Trümbach D, Götz M, Stricker SH, Ninkovic J. Innate Immune Pathways Promote Oligodendrocyte Progenitor Cell Recruitment to the Injury Site in Adult Zebrafish Brain. Cells 2022; 11:cells11030520. [PMID: 35159329 PMCID: PMC8834209 DOI: 10.3390/cells11030520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 01/18/2022] [Accepted: 01/18/2022] [Indexed: 01/13/2023] Open
Abstract
The oligodendrocyte progenitors (OPCs) are at the front of the glial reaction to the traumatic brain injury. However, regulatory pathways steering the OPC reaction as well as the role of reactive OPCs remain largely unknown. Here, we compared a long-lasting, exacerbated reaction of OPCs to the adult zebrafish brain injury with a timely restricted OPC activation to identify the specific molecular mechanisms regulating OPC reactivity and their contribution to regeneration. We demonstrated that the influx of the cerebrospinal fluid into the brain parenchyma after injury simultaneously activates the toll-like receptor 2 (Tlr2) and the chemokine receptor 3 (Cxcr3) innate immunity pathways, leading to increased OPC proliferation and thereby exacerbated glial reactivity. These pathways were critical for long-lasting OPC accumulation even after the ablation of microglia and infiltrating monocytes. Importantly, interference with the Tlr1/2 and Cxcr3 pathways after injury alleviated reactive gliosis, increased new neuron recruitment, and improved tissue restoration.
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Affiliation(s)
- Rosario Sanchez-Gonzalez
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Department Biology II, University of Munich, 80539 München, Germany;
| | - Christina Koupourtidou
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Biomedical Center (BMC), Division of Cell Biology and Anatomy, Faculty of Medicine, LMU Munich, 80539 München, Germany
- Graduate School Systemic Neurosciences, LMU, 80539 Munich, Germany
| | - Tjasa Lepko
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Biomedical Center (BMC), Division of Cell Biology and Anatomy, Faculty of Medicine, LMU Munich, 80539 München, Germany
- Graduate School Systemic Neurosciences, LMU, 80539 Munich, Germany
| | - Alessandro Zambusi
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Biomedical Center (BMC), Division of Cell Biology and Anatomy, Faculty of Medicine, LMU Munich, 80539 München, Germany
- Graduate School Systemic Neurosciences, LMU, 80539 Munich, Germany
| | - Klara Tereza Novoselc
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Biomedical Center (BMC), Division of Cell Biology and Anatomy, Faculty of Medicine, LMU Munich, 80539 München, Germany
- Graduate School Systemic Neurosciences, LMU, 80539 Munich, Germany
| | - Tamara Durovic
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Biomedical Center (BMC), Division of Cell Biology and Anatomy, Faculty of Medicine, LMU Munich, 80539 München, Germany
- Graduate School Systemic Neurosciences, LMU, 80539 Munich, Germany
| | - Sven Aschenbroich
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Biomedical Center (BMC), Division of Cell Biology and Anatomy, Faculty of Medicine, LMU Munich, 80539 München, Germany
- Graduate School Systemic Neurosciences, LMU, 80539 Munich, Germany
| | - Veronika Schwarz
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Biomedical Center (BMC), Division of Cell Biology and Anatomy, Faculty of Medicine, LMU Munich, 80539 München, Germany
- Graduate School Systemic Neurosciences, LMU, 80539 Munich, Germany
| | - Christopher T. Breunig
- Reprogramming and Regeneration, Biomedical Center (BMC), Physiological Genomics, Faculty of Medicine, LMU Munich, 80539 München, Germany; (C.T.B.); (S.H.S.)
- Epigenetic Engineering, Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany
| | - Hans Straka
- Department Biology II, University of Munich, 80539 München, Germany;
| | - Hagen B. Huttner
- Department of Neurology, Justus-Liebig-University Giessen, Klinikstrasse 33, 35392 Giessen, Germany;
| | - Martin Irmler
- Institute of Experimental Genetics, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (M.I.); (J.B.)
| | - Johannes Beckers
- Institute of Experimental Genetics, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (M.I.); (J.B.)
- German Center for Diabetes Research (DZD e.V.), 85764 Neuherberg, Germany
- Chair of Experimental Genetics, School of Life Sciences Weihenstephan, Technical University Munich, 80333 München, Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (W.W.); (D.T.)
- Munich Cluster for Systems Neurology SYNERGY, LMU, 80539 Munich, Germany
- Chair of Developmental Genetics c/o Helmholtz Zentrum München, School of Life Sciences Weihenstephan, Technical University Munich, 80333 München, Germany
- German Center for Neurodegenerative Diseases (DZNE), Site Munich, 80539 Munich, Germany
| | - Andreas Zwergal
- Department of Neurology, Ludwig-Maximilians University, Campus Grosshadern, 81377 Munich, Germany;
| | - Tamas Schauer
- Biomedical Center (BMC), Bioinformatic Core Facility, Faculty of Medicine, LMU Munich, 80539 München, Germany; (T.S.); (T.S.)
| | - Tobias Straub
- Biomedical Center (BMC), Bioinformatic Core Facility, Faculty of Medicine, LMU Munich, 80539 München, Germany; (T.S.); (T.S.)
| | - Tim Czopka
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH8 9YL, UK;
| | - Dietrich Trümbach
- Institute of Developmental Genetics, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (W.W.); (D.T.)
| | - Magdalena Götz
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Munich Cluster for Systems Neurology SYNERGY, LMU, 80539 Munich, Germany
- Biomedical Center (BMC), Division of Physiological Genomics, Faculty of Medicine, LMU Munich, 80539 München, Germany
| | - Stefan H. Stricker
- Reprogramming and Regeneration, Biomedical Center (BMC), Physiological Genomics, Faculty of Medicine, LMU Munich, 80539 München, Germany; (C.T.B.); (S.H.S.)
- Epigenetic Engineering, Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany
| | - Jovica Ninkovic
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Oberschleißheim, Germany; (R.S.-G.); (C.K.); (T.L.); (A.Z.); (K.T.N.); (T.D.); (S.A.); (V.S.); (M.G.)
- Biomedical Center (BMC), Division of Cell Biology and Anatomy, Faculty of Medicine, LMU Munich, 80539 München, Germany
- Munich Cluster for Systems Neurology SYNERGY, LMU, 80539 Munich, Germany
- Correspondence:
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16
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Riley SE, Feng Y, Hansen CG. Hippo-Yap/Taz signalling in zebrafish regeneration. NPJ Regen Med 2022; 7:9. [PMID: 35087046 PMCID: PMC8795407 DOI: 10.1038/s41536-022-00209-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 12/14/2021] [Indexed: 12/29/2022] Open
Abstract
The extent of tissue regeneration varies widely between species. Mammals have a limited regenerative capacity whilst lower vertebrates such as the zebrafish (Danio rerio), a freshwater teleost, can robustly regenerate a range of tissues, including the spinal cord, heart, and fin. The molecular and cellular basis of this altered response is one of intense investigation. In this review, we summarise the current understanding of the association between zebrafish regeneration and Hippo pathway function, a phosphorylation cascade that regulates cell proliferation, mechanotransduction, stem cell fate, and tumorigenesis, amongst others. We also compare this function to Hippo pathway activity in the regenerative response of other species. We find that the Hippo pathway effectors Yap/Taz facilitate zebrafish regeneration and that this appears to be latent in mammals, suggesting that therapeutically promoting precise and temporal YAP/TAZ signalling in humans may enhance regeneration and hence reduce morbidity.
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Affiliation(s)
- Susanna E Riley
- University of Edinburgh Centre for Inflammation Research, Institute for Regeneration and Repair, Queen's Medical Research Institute, Edinburgh bioQuarter, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Yi Feng
- University of Edinburgh Centre for Inflammation Research, Institute for Regeneration and Repair, Queen's Medical Research Institute, Edinburgh bioQuarter, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Carsten Gram Hansen
- University of Edinburgh Centre for Inflammation Research, Institute for Regeneration and Repair, Queen's Medical Research Institute, Edinburgh bioQuarter, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK.
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17
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Prophylactic Activation of Shh Signaling Attenuates TBI-Induced Seizures in Zebrafish by Modulating Glutamate Excitotoxicity through Eaat2a. Biomedicines 2021; 10:biomedicines10010032. [PMID: 35052712 PMCID: PMC8773121 DOI: 10.3390/biomedicines10010032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/16/2021] [Accepted: 12/22/2021] [Indexed: 12/21/2022] Open
Abstract
Approximately 2 million individuals experience a traumatic brain injury (TBI) every year in the United States. Secondary injury begins within minutes after TBI, with alterations in cellular function and chemical signaling that contribute to excitotoxicity. Post-traumatic seizures (PTS) are experienced in an increasing number of TBI individuals that also display resistance to traditional anti-seizure medications (ASMs). Sonic hedgehog (Shh) is a signaling pathway that is upregulated following central nervous system damage in zebrafish and aids injury-induced regeneration. Using a modified Marmarou weight drop on adult zebrafish, we examined PTS following TBI and Shh modulation. We found that inhibiting Shh signaling by cyclopamine significantly increased PTS in TBI fish, prolonged the timeframe PTS was observed, and decreased survival across all TBI severities. Shh-inhibited TBI fish failed to respond to traditional ASMs, but were attenuated when treated with CNQX, which blocks ionotropic glutamate receptors. We found that the Smoothened agonist, purmorphamine, increased Eaat2a expression in undamaged brains compared to untreated controls, and purmorphamine treatment reduced glutamate excitotoxicity following TBI. Similarly, purmorphamine reduced PTS, edema, and cognitive deficits in TBI fish, while these pathologies were increased and/or prolonged in cyclopamine-treated TBI fish. However, the increased severity of TBI phenotypes with cyclopamine was reduced by cotreating fish with ceftriaxone, which induces Eaat2a expression. Collectively, these data suggest that Shh signaling induces Eaat2a expression and plays a role in regulating TBI-induced glutamate excitotoxicity and TBI sequelae.
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18
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Cavone L, McCann T, Drake LK, Aguzzi EA, Oprişoreanu AM, Pedersen E, Sandi S, Selvarajah J, Tsarouchas TM, Wehner D, Keatinge M, Mysiak KS, Henderson BEP, Dobie R, Henderson NC, Becker T, Becker CG. A unique macrophage subpopulation signals directly to progenitor cells to promote regenerative neurogenesis in the zebrafish spinal cord. Dev Cell 2021; 56:1617-1630.e6. [PMID: 34033756 DOI: 10.1016/j.devcel.2021.04.031] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 03/15/2021] [Accepted: 04/28/2021] [Indexed: 12/14/2022]
Abstract
Central nervous system injury re-initiates neurogenesis in anamniotes (amphibians and fishes), but not in mammals. Activation of the innate immune system promotes regenerative neurogenesis, but it is fundamentally unknown whether this is indirect through the activation of known developmental signaling pathways or whether immune cells directly signal to progenitor cells using mechanisms that are unique to regeneration. Using single-cell RNA-seq of progenitor cells and macrophages, as well as cell-type-specific manipulations, we provide evidence for a direct signaling axis from specific lesion-activated macrophages to spinal progenitor cells to promote regenerative neurogenesis in zebrafish. Mechanistically, TNFa from pro-regenerative macrophages induces Tnfrsf1a-mediated AP-1 activity in progenitors to increase regeneration-promoting expression of hdac1 and neurogenesis. This establishes the principle that macrophages directly communicate to spinal progenitor cells via non-developmental signals after injury, providing potential targets for future interventions in the regeneration-deficient spinal cord of mammals.
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Affiliation(s)
- Leonardo Cavone
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Tess McCann
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Louisa K Drake
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Erika A Aguzzi
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Ana-Maria Oprişoreanu
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Elisa Pedersen
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Soe Sandi
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Jathurshan Selvarajah
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Themistoklis M Tsarouchas
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Daniel Wehner
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK; Max Planck Institute for the Science of Light, Staudtstraße 2, Erlangen 91058, Germany; Max-Planck-Zentrum für Physik und Medizin, Staudtstraße 2, Erlangen 91058, Germany
| | - Marcus Keatinge
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Karolina S Mysiak
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Beth E P Henderson
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Ross Dobie
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Neil C Henderson
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK; MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Thomas Becker
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
| | - Catherina G Becker
- Centre for Discovery Brain Sciences, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK; Euan MacDonald Centre for Motor Neurone Disease Research University of Edinburgh, Edinburgh, UK.
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19
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Zeng CW, Kamei Y, Shigenobu S, Sheu JC, Tsai HJ. Injury-induced Cavl-expressing cells at lesion rostral side play major roles in spinal cord regeneration. Open Biol 2021; 11:200304. [PMID: 33622104 PMCID: PMC8061693 DOI: 10.1098/rsob.200304] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The extent of cellular heterogeneity involved in neuronal regeneration after spinal cord injury (SCI) remains unclear. Therefore, we established stress-responsive transgenic zebrafish embryos with SCI. As a result, we found an SCI-induced cell population, termed SCI stress-responsive regenerating cells (SrRCs), essential for neuronal regeneration post-SCI. SrRCs were mostly composed of subtypes of radial glia (RGs-SrRCs) and neuron stem/progenitor cells (NSPCs-SrRCs) that are able to differentiate into neurons, and they formed a bridge across the lesion and connected with neighbouring undamaged motor neurons post-SCI. Compared to SrRCs at the caudal side of the SCI site (caudal-SrRCs), rostral-SrRCs participated more actively in neuronal regeneration. After RNA-seq analysis, we discovered that caveolin 1 (cav1) was significantly upregulated in rostral-SrRCs and that cav1 was responsible for the axonal regrowth and regenerative capability of rostral-SrRCs. Collectively, we define a specific SCI-induced cell population, SrRCs, involved in neuronal regeneration, demonstrate that rostral-SrRCs exhibit higher neuronal differentiation capability and prove that cav1 is predominantly expressed in rostral-SrRCs, playing a major role in neuronal regeneration after SCI.
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Affiliation(s)
- Chih-Wei Zeng
- Institute of Molecular and Cellular Biology, College of Life Science, National Taiwan University, Taipei 10617, Taiwan.,Liver Disease Prevention and Treatment Research Foundation, Taipei 10008, Taiwan
| | - Yasuhiro Kamei
- Spectrography and Bioimaging Facility, National Institute for Basic Biology (NIBB), National Institutes of Natural Sciences (NINS), Okazaki 444-8585, Japan.,Department of Basic Biology, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan
| | - Shuji Shigenobu
- Department of Basic Biology, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan.,Functional Genomics Facility, NIBB, NINS, Okazaki 444-8585, Japan
| | - Jin-Chuan Sheu
- Liver Disease Prevention and Treatment Research Foundation, Taipei 10008, Taiwan
| | - Huai-Jen Tsai
- Institute of Biomedical Sciences, Mackay Medical College, New Taipei City 25245, Taiwan.,Department of Life Science, Fu Jen Catholic University, New Taipei City 242062, Taiwan
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20
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Massoz L, Dupont MA, Manfroid I. Zebra-Fishing for Regenerative Awakening in Mammals. Biomedicines 2021; 9:65. [PMID: 33445518 PMCID: PMC7827770 DOI: 10.3390/biomedicines9010065] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 02/07/2023] Open
Abstract
Regeneration is defined as the ability to regrow an organ or a tissue destroyed by degeneration or injury. Many human degenerative diseases and pathologies, currently incurable, could be cured if functional tissues or cells could be restored. Unfortunately, humans and more generally mammals have limited regenerative capabilities, capacities that are even further declining with age, contrary to simpler organisms. Initially thought to be lost during evolution, several studies have revealed that regenerative mechanisms are still present in mammals but are latent and thus they could be stimulated. To do so there is a pressing need to identify the fundamental mechanisms of regeneration in species able to efficiently regenerate. Thanks to its ability to regenerate most of its organs and tissues, the zebrafish has become a powerful model organism in regenerative biology and has recently engendered a number of studies attesting the validity of awakening the regenerative potential in mammals. In this review we highlight studies, particularly in the liver, pancreas, retina, heart, brain and spinal cord, which have identified conserved regenerative molecular events that proved to be beneficial to restore murine and even human cells and which helped clarify the real clinical translation potential of zebrafish research to mammals.
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Affiliation(s)
| | | | - Isabelle Manfroid
- Zebrafish Development and Disease Models Laboratory, GIGA-Stem Cells, University of Liège, B-4000 Liège, Belgium; (L.M.); (M.A.D.)
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21
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Giarretta I, Pola R. Arteriovenous malformations: the newest Sonic hedgehog game in the postnatal brain. Neural Regen Res 2021; 16:996-998. [PMID: 33229750 PMCID: PMC8178779 DOI: 10.4103/1673-5374.297077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Igor Giarretta
- Department of Translational Medicine and Surgery, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, School of Medicine, Rome, Italy
| | - Roberto Pola
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, School of Medicine, Rome, Italy
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22
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Hedgehog Signaling Regulates Neurogenesis in the Larval and Adult Zebrafish Hypothalamus. eNeuro 2020; 7:ENEURO.0226-20.2020. [PMID: 33106384 PMCID: PMC7769882 DOI: 10.1523/eneuro.0226-20.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 09/21/2020] [Accepted: 09/28/2020] [Indexed: 12/15/2022] Open
Abstract
Neurogenesis is now known to play a role in adult hypothalamic function, yet the cell-cell mechanisms regulating this neurogenesis remain poorly understood. Here, we show that Hedgehog (Hh)/Gli signaling positively regulates hypothalamic neurogenesis in both larval and adult zebrafish and is necessary and sufficient for normal hypothalamic proliferation rates. Hh-responsive radial glia represent a relatively highly proliferative precursor population that gives rise to dopaminergic, serotonergic, and GABAergic neurons. In situ and transgenic reporter analyses revealed substantial heterogeneity in cell-cell signaling within the hypothalamic niche, with slow cycling Nestin-expressing cells residing among distinct and overlapping populations of Sonic Hh (Shh)-expressing, Hh-responsive, Notch-responsive, and Wnt-responsive radial glia. This work shows for the first time that Hh/Gli signaling is a key component of the complex cell-cell signaling environment that regulates hypothalamic neurogenesis throughout life.
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23
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Labusch M, Mancini L, Morizet D, Bally-Cuif L. Conserved and Divergent Features of Adult Neurogenesis in Zebrafish. Front Cell Dev Biol 2020; 8:525. [PMID: 32695781 PMCID: PMC7338623 DOI: 10.3389/fcell.2020.00525] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/03/2020] [Indexed: 12/14/2022] Open
Abstract
Adult neurogenesis, i.e., the generation of neurons from neural stem cells (NSCs) in the adult brain, contributes to brain plasticity in all vertebrates. It varies, however, greatly in extent, location and physiological characteristics between species. During the last decade, the teleost zebrafish (D. rerio) was increasingly used to study the molecular and cellular properties of adult NSCs, in particular as a prominent NSC population was discovered at the ventricular surface of the dorsal telencephalon (pallium), in territories homologous to the adult neurogenic niches of rodents. This model, for its specific features (large NSC population, amenability to intravital imaging, high regenerative capacity) allowed rapid progress in the characterization of basic adult NSC features. We review here these findings, with specific comparisons with the situation in rodents. We specifically discuss the cellular nature of NSCs (astroglial or neuroepithelial cells), their heterogeneities and their neurogenic lineages, and the mechanisms controlling NSC quiescence and fate choices, which all impact the neurogenic output. We further discuss the regulation of NSC activity in response to physiological triggers and non-physiological conditions such as regenerative contexts.
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Affiliation(s)
- Miriam Labusch
- Zebrafish Neurogenetics Unit, Institut Pasteur, UMR 3738, CNRS, Team Supported by the Ligue Nationale Contre le Cancer, Paris, France.,Sorbonne Université, Collège Doctoral, Paris, France
| | - Laure Mancini
- Zebrafish Neurogenetics Unit, Institut Pasteur, UMR 3738, CNRS, Team Supported by the Ligue Nationale Contre le Cancer, Paris, France.,Sorbonne Université, Collège Doctoral, Paris, France
| | - David Morizet
- Zebrafish Neurogenetics Unit, Institut Pasteur, UMR 3738, CNRS, Team Supported by the Ligue Nationale Contre le Cancer, Paris, France.,Sorbonne Université, Collège Doctoral, Paris, France
| | - Laure Bally-Cuif
- Zebrafish Neurogenetics Unit, Institut Pasteur, UMR 3738, CNRS, Team Supported by the Ligue Nationale Contre le Cancer, Paris, France
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24
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Mruk K, Ciepla P, Piza PA, Alnaqib MA, Chen JK. Targeted cell ablation in zebrafish using optogenetic transcriptional control. Development 2020; 147:dev183640. [PMID: 32414936 PMCID: PMC7328002 DOI: 10.1242/dev.183640] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 04/22/2020] [Indexed: 12/11/2022]
Abstract
Cell ablation is a powerful method for elucidating the contributions of individual cell populations to embryonic development and tissue regeneration. Targeted cell loss in whole organisms has been typically achieved through expression of a cytotoxic or prodrug-activating gene product in the cell type of interest. This approach depends on the availability of tissue-specific promoters, and it does not allow further spatial selectivity within the promoter-defined region(s). To address this limitation, we have used the light-inducible GAVPO transactivator in combination with two genetically encoded cell-ablation technologies: the nitroreductase/nitrofuran system and a cytotoxic variant of the M2 ion channel. Our studies establish ablative methods that provide the tissue specificity afforded by cis-regulatory elements and the conditionality of optogenetics. Our studies also demonstrate differences between the nitroreductase and M2 systems that influence their efficacies for specific applications. Using this integrative approach, we have ablated cells in zebrafish embryos with both spatial and temporal control.
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Affiliation(s)
- Karen Mruk
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
- School of Pharmacy, University of Wyoming, Laramie, WY 82071, USA
| | - Paulina Ciepla
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Patrick A Piza
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Mohammad A Alnaqib
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - James K Chen
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
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25
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Cigliola V, Becker CJ, Poss KD. Building bridges, not walls: spinal cord regeneration in zebrafish. Dis Model Mech 2020; 13:13/5/dmm044131. [PMID: 32461216 PMCID: PMC7272344 DOI: 10.1242/dmm.044131] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Spinal cord injury is a devastating condition in which massive cell death and disruption of neural circuitry lead to long-term chronic functional impairment and paralysis. In mammals, spinal cord tissue has minimal capacity to regenerate after injury. In stark contrast, the regeneration of a completely transected spinal cord and accompanying reversal of paralysis in adult zebrafish is arguably one of the most spectacular biological phenomena in nature. Here, we review reports from the last decade that dissect the mechanisms of spinal cord regeneration in zebrafish. We highlight recent progress as well as areas requiring emphasis in a line of study that has great potential to uncover strategies for human spinal cord repair. Summary: Unlike mammals, teleost fish are capable of efficient, spontaneous recovery after a paralyzing spinal cord injury. Here, we highlight the major events through which laboratory model zebrafish regenerate spinal cord tissue.
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Affiliation(s)
- Valentina Cigliola
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.,Regeneration Next, Duke University, Durham, NC 27710, USA
| | - Clayton J Becker
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.,Regeneration Next, Duke University, Durham, NC 27710, USA
| | - Kenneth D Poss
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA .,Regeneration Next, Duke University, Durham, NC 27710, USA
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26
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Kakebeen AD, Chitsazan AD, Williams MC, Saunders LM, Wills AE. Chromatin accessibility dynamics and single cell RNA-Seq reveal new regulators of regeneration in neural progenitors. eLife 2020; 9:e52648. [PMID: 32338593 PMCID: PMC7250574 DOI: 10.7554/elife.52648] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 04/25/2020] [Indexed: 12/24/2022] Open
Abstract
Vertebrate appendage regeneration requires precisely coordinated remodeling of the transcriptional landscape to enable the growth and differentiation of new tissue, a process executed over multiple days and across dozens of cell types. The heterogeneity of tissues and temporally-sensitive fate decisions involved has made it difficult to articulate the gene regulatory programs enabling regeneration of individual cell types. To better understand how a regenerative program is fulfilled by neural progenitor cells (NPCs) of the spinal cord, we analyzed pax6-expressing NPCs isolated from regenerating Xenopus tropicalis tails. By intersecting chromatin accessibility data with single-cell transcriptomics, we find that NPCs place an early priority on neuronal differentiation. Late in regeneration, the priority returns to proliferation. Our analyses identify Pbx3 and Meis1 as critical regulators of tail regeneration and axon organization. Overall, we use transcriptional regulatory dynamics to present a new model for cell fate decisions and their regulators in NPCs during regeneration.
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Affiliation(s)
| | | | | | - Lauren M Saunders
- Department of Genome Sciences, University of WashingtonSeattleUnited States
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27
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28
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Sabin KZ, Echeverri K. The role of the immune system during regeneration of the central nervous system. ACTA ACUST UNITED AC 2019; 7. [PMID: 32864529 DOI: 10.1016/j.regen.2019.100023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Central nervous system damage in mammals leads to neuronal cell death, axonal degeneration, and formation of a glial scar resulting in functional and behavioral defects. Other vertebrates, like fish and salamanders, have retained the ability to functionally regenerate after central nervous system injury. To date research from many research organisms has led to a more concise understanding of the response of local neural cells to injury. However, it has become clear that non-neural cells of the immune system play an important role in determining the tissue response to injury. In this review we briefly consider the mammalian response to injury compared to organisms with the natural ability to regenerate. We then discuss similarities and differences in how cells of the innate and adaptive immune system respond and contribute to tissue repair in various species.
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Affiliation(s)
- K Z Sabin
- Eugene Bell Center for Regenerative Biology & Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA 02543 USA
| | - K Echeverri
- Eugene Bell Center for Regenerative Biology & Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA 02543 USA
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29
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Ceci M, Mariano V, Romano N. Zebrafish as a translational regeneration model to study the activation of neural stem cells and role of their environment. Rev Neurosci 2019; 30:45-66. [PMID: 30067512 DOI: 10.1515/revneuro-2018-0020] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 04/27/2018] [Indexed: 02/07/2023]
Abstract
The review is an overview of the current knowledge of neuronal regeneration properties in mammals and fish. The ability to regenerate the damaged parts of the nervous tissue has been demonstrated in all vertebrates. Notably, fish and amphibians have the highest capacity for neurogenesis, whereas reptiles and birds are able to only regenerate specific regions of the brain, while mammals have reduced capacity for neurogenesis. Zebrafish (Danio rerio) is a promising model of study because lesions in the brain or complete cross-section of the spinal cord are followed by an effective neuro-regeneration that successfully restores the motor function. In the brain and the spinal cord of zebrafish, stem cell activity is always able to re-activate the molecular programs required for central nervous system regeneration. In mammals, traumatic brain injuries are followed by reduced neurogenesis and poor axonal regeneration, often insufficient to functionally restore the nervous tissue, while spinal injuries are not repaired at all. The environment that surrounds the stem cell niche constituted by connective tissue and stimulating factors, including pro-inflammation molecules, seems to be a determinant in triggering stem cell proliferation and/or the trans-differentiation of connective elements (mainly fibroblasts). Investigating and comparing the neuronal regeneration in zebrafish and mammals may lead to a better understanding of the mechanisms behind neurogenesis, and the failure of the regenerative response in mammals, first of all, the role of inflammation, considered the main inhibitor of the neuronal regeneration.
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Affiliation(s)
- Marcello Ceci
- Department of Ecological and Biological Sciences, University of Tuscia, largo dell'Università, I-01100 Viterbo, Italy
| | - Vittoria Mariano
- Department of Fundamental Neurosciences, University of Lausanne, CH-1005 Lausanne, Switzerland
| | - Nicla Romano
- Department of Ecological and Biological Sciences, University of Tuscia, largo dell'Università, I-01100 Viterbo, Italy
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30
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Nelson CM, Lennon VA, Lee H, Krug RG, Kamalova A, Madigan NN, Clark KJ, Windebank AJ, Henley JR. Glucocorticoids Target Ependymal Glia and Inhibit Repair of the Injured Spinal Cord. Front Cell Dev Biol 2019; 7:56. [PMID: 31069223 PMCID: PMC6491705 DOI: 10.3389/fcell.2019.00056] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 03/29/2019] [Indexed: 01/16/2023] Open
Abstract
Following injury, the mammalian spinal cord forms a glial scar and fails to regenerate. In contrast, vertebrate fish spinal cord tissue regenerates significantly to restore function. Cord transection in zebrafish (Danio rerio) initially causes paralysis and neural cell death. Subsequently, ependymal glia proliferate, bipolar glia extend across the lesion, and new neurons are born; axons from spared and nascent neurons extend along trans-lesional glial bridges to restore functional connectivity. Here we report that glucocorticoids, used in the clinical management of spinal cord injury, directly inhibit neural repair by targeting ependymal glia independently of hematogenous cells and microglia. After transecting injury, the glucocorticoid receptor in ependymal glia is regulated differentially in zebrafish (becoming inactive) vs. the rat (becoming active). Glucocorticoid blockade of neural regeneration via a direct effect on ependymal glia has important therapeutic implications for the putative benefit of corticosteroids in early management of spinal cord injury.
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Affiliation(s)
- Craig M Nelson
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States.,Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States
| | - Vanda A Lennon
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.,Department of Neurology, Mayo Clinic, Rochester, MN, United States.,Department of Immunology, Mayo Clinic, Rochester, MN, United States
| | - Han Lee
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States
| | - Randall G Krug
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States
| | - Aichurok Kamalova
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States
| | | | - Karl J Clark
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States
| | | | - John R Henley
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States.,Department of Physiology and Biomedical Engineering, Mayo Graduate School, Mayo Clinic College of Medicine and Science, Rochester, MN, United States
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31
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Pushchina EV, Varaksin AA. Neurolin expression in the optic nerve and immunoreactivity of Pax6-positive niches in the brain of rainbow trout ( Oncorhynchus mykiss) after unilateral eye injury. Neural Regen Res 2019; 14:156-171. [PMID: 30531090 PMCID: PMC6263006 DOI: 10.4103/1673-5374.243721] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
In contrast to astrocytes in mammals, fish astrocytes promote axon regeneration after brain injury and actively participate in the regeneration process. Neurolin, a regeneration-associated, Zn8-labeled protein, is involved in the repair of damaged optic nerve in goldfish. At 1 week after unilateral eye injury, the expression of neurolin in the optic nerve and chiasm, and the expression of Pax6 that influences nervous system development in various brain regions in the rainbow trout (Oncorhynchus mykiss) were detected. Immunohistochemical staining revealed that the number of Zn8+ cells in the optic nerve head and intraorbital segment was obviously increased, and the increase in Zn8+ cells was also observed in the proximal and distal parts of injured optic nerve. This suggests that Zn8+ astrocytes participate in optic nerve regeneration. ELISA results revealed that Pax6 protein increased obviously at 1 week post-injury. Immunohistochemical staining revealed the appearance of Pax6+ neurogenic niches and a larger number of neural precursor cells, which are mainly from Pax6+ radial glia cells, in the nuclei of the diencephalon and optic tectum of rainbow trout (Oncorhynchus mykiss). Taken together, unilateral eye injury can cause optic nerve reaction, and the formation of neurogenic niches is likely a compensation phenomenon during the repair process of optic nerve injury in rainbow trout (Oncorhynchus mykiss).
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Affiliation(s)
- Evgeniya V Pushchina
- National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia; A.A. Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, Kiev, Ukraine
| | - Anatoly A Varaksin
- National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia
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32
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Goldshmit Y, Tang JKKY, Siegel AL, Nguyen PD, Kaslin J, Currie PD, Jusuf PR. Different Fgfs have distinct roles in regulating neurogenesis after spinal cord injury in zebrafish. Neural Dev 2018; 13:24. [PMID: 30447699 PMCID: PMC6240426 DOI: 10.1186/s13064-018-0122-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 11/08/2018] [Indexed: 11/10/2022] Open
Abstract
Background Despite conserved developmental processes and organization of the vertebrate central nervous system, only some vertebrates including zebrafish can efficiently regenerate neural damage including after spinal cord injury. The mammalian spinal cord shows very limited regeneration and neurogenesis, resulting in permanent life-long functional impairment. Therefore, there is an urgent need to identify the cellular and molecular mechanisms that can drive efficient vertebrate neurogenesis following injury. A key pathway implicated in zebrafish neurogenesis is fibroblast growth factor signaling. Methods In the present study we investigated the roles of distinct fibroblast growth factor members and their receptors in facilitating different aspects of neural development and regeneration at different timepoints following spinal cord injury. After spinal cord injury in adults and during larval development, loss and/or gain of Fgf signaling was combined with immunohistochemistry, in situ hybridization and transgenes marking motor neuron populations in in vivo zebrafish and in vitro mammalian PC12 cell culture models. Results Fgf3 drives neurogenesis of Islet1 expressing motor neuron subtypes and mediate axonogenesis in cMet expressing motor neuron subtypes. We also demonstrate that the role of Fgf members are not necessarily simple recapitulating development. During development Fgf2, Fgf3 and Fgf8 mediate neurogenesis of Islet1 expressing neurons and neuronal sprouting of both, Islet1 and cMet expressing motor neurons. Strikingly in mammalian PC12 cells, all three Fgfs increased cell proliferation, however, only Fgf2 and to some extent Fgf8, but not Fgf3 facilitated neurite outgrowth. Conclusions This study demonstrates differential Fgf member roles during neural development and adult regeneration, including in driving neural proliferation and neurite outgrowth of distinct spinal cord neuron populations, suggesting that factors including Fgf type, age of the organism, timing of expression, requirements for different neuronal populations could be tailored to best drive all of the required regenerative processes.
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Affiliation(s)
- Yona Goldshmit
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia.,Steyer School of Health Professions, Sackler School of Medicine, Tel-Aviv University, P.O. Box 39040, 6997801, Tel Aviv, Israel
| | - Jean Kitty K Y Tang
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Ashley L Siegel
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Phong D Nguyen
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Jan Kaslin
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Peter D Currie
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Patricia R Jusuf
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia. .,School of Biosciences, University of Melbourne, Parkville, VIC, 3010, Australia.
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33
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Becker CG, Becker T, Hugnot JP. The spinal ependymal zone as a source of endogenous repair cells across vertebrates. Prog Neurobiol 2018; 170:67-80. [DOI: 10.1016/j.pneurobio.2018.04.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 01/30/2018] [Accepted: 04/05/2018] [Indexed: 02/07/2023]
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34
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Ribeiro A, Monteiro JF, Certal AC, Cristovão AM, Saúde L. Foxj1a is expressed in ependymal precursors, controls central canal position and is activated in new ependymal cells during regeneration in zebrafish. Open Biol 2018; 7:rsob.170139. [PMID: 29162726 PMCID: PMC5717339 DOI: 10.1098/rsob.170139] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 10/27/2017] [Indexed: 01/06/2023] Open
Abstract
Zebrafish are able to regenerate the spinal cord and recover motor and sensory functions upon severe injury, through the activation of cells located at the ependymal canal. Here, we show that cells surrounding the ependymal canal in the adult zebrafish spinal cord express Foxj1a. We demonstrate that ependymal cells express Foxj1a from their birth in the embryonic neural tube and that Foxj1a activity is required for the final positioning of the ependymal canal. We also show that in response to spinal cord injury, Foxj1a ependymal cells actively proliferate and contribute to the restoration of the spinal cord structure. Finally, this study reveals that Foxj1a expression in the injured spinal cord is regulated by regulatory elements activated during regeneration. These data establish Foxj1a as a pan-ependymal marker in development, homeostasis and regeneration and may help identify the signals that enable this progenitor population to replace lost cells after spinal cord injury.
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Affiliation(s)
- Ana Ribeiro
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Joana F Monteiro
- Champalimaud Research, Champalimaud Centre for the Unknown, Lisboa, Portugal
| | - Ana C Certal
- Champalimaud Research, Champalimaud Centre for the Unknown, Lisboa, Portugal
| | - Ana M Cristovão
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Leonor Saúde
- Instituto de Medicina Molecular e Instituto de Histologia e Biologia do Desenvolvimento, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
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35
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Cardozo MJ, Mysiak KS, Becker T, Becker CG. Reduce, reuse, recycle – Developmental signals in spinal cord regeneration. Dev Biol 2017; 432:53-62. [DOI: 10.1016/j.ydbio.2017.05.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 02/03/2017] [Accepted: 05/11/2017] [Indexed: 02/06/2023]
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36
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Gilbert EAB, Vickaryous MK. Neural stem/progenitor cells are activated during tail regeneration in the leopard gecko (Eublepharis macularius). J Comp Neurol 2017; 526:285-309. [PMID: 28980312 DOI: 10.1002/cne.24335] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Revised: 09/16/2017] [Accepted: 09/17/2017] [Indexed: 12/15/2022]
Abstract
As for many lizards, the leopard gecko (Eublepharis macularius) can self-detach its tail to avoid predation and then regenerate a replacement. The replacement tail includes a regenerated spinal cord with a simple morphology: an ependymal layer surrounded by nerve tracts. We hypothesized that cells within the ependymal layer of the original spinal cord include populations of neural stem/progenitor cells (NSPCs) that contribute to the regenerated spinal cord. Prior to tail loss, we performed a bromodeoxyuridine pulse-chase experiment and found that a subset of ependymal layer cells (ELCs) were label-retaining after a 140-day chase period. Next, we conducted a detailed spatiotemporal characterization of these cells before, during, and after tail regeneration. Our findings show that SOX2, a hallmark protein of NSPCs, is constitutively expressed by virtually all ELCs before, during, and after regeneration. We also found that during regeneration, ELCs express an expanded panel of NSPC and lineage-restricted progenitor cell markers, including MSI-1, SOX9, and TUJ1. Using electron microscopy, we determined that multiciliated, uniciliated, and biciliated cells are present, although the latter was only observed in regenerated spinal cords. Our results demonstrate that cells within the ependymal layer of the original, regenerating and fully regenerate spinal cord represent a heterogeneous population. These include radial glia comparable to Type E and Type B cells, and a neuronal-like population of cerebrospinal fluid-contacting cells. We propose that spinal cord regeneration in geckos represents a truncation of the restorative trajectory observed in some urodeles and teleosts, resulting in the formation of a structurally distinct replacement.
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Affiliation(s)
- E A B Gilbert
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - M K Vickaryous
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
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37
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Kroehne V, Tsata V, Marrone L, Froeb C, Reinhardt S, Gompf A, Dahl A, Sterneckert J, Reimer MM. Primary Spinal OPC Culture System from Adult Zebrafish to Study Oligodendrocyte Differentiation In Vitro. Front Cell Neurosci 2017; 11:284. [PMID: 28959189 PMCID: PMC5603699 DOI: 10.3389/fncel.2017.00284] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 08/31/2017] [Indexed: 01/24/2023] Open
Abstract
Endogenous oligodendrocyte progenitor cells (OPCs) are a promising target to improve functional recovery after spinal cord injury (SCI) by remyelinating denuded, and therefore vulnerable, axons. Demyelination is the result of a primary insult and secondary injury, leading to conduction blocks and long-term degeneration of the axons, which subsequently can lead to the loss of their neurons. In response to SCI, dormant OPCs can be activated and subsequently start to proliferate and differentiate into mature myelinating oligodendrocytes (OLs). Therefore, researchers strive to control OPC responses, and utilize small molecule screening approaches in order to identify mechanisms of OPC activation, proliferation, migration and differentiation. In zebrafish, OPCs remyelinate axons of the optic tract after lysophosphatidylcholine (LPC)-induced demyelination back to full thickness myelin sheaths. In contrast to zebrafish, mammalian OPCs are highly vulnerable to excitotoxic stress, a cause of secondary injury, and remyelination remains insufficient. Generally, injury induced remyelination leads to shorter internodes and thinner myelin sheaths in mammals. In this study, we show that myelin sheaths are lost early after a complete spinal transection injury, but are re-established within 14 days after lesion. We introduce a novel, easy-to-use, inexpensive and highly reproducible OPC culture system based on dormant spinal OPCs from adult zebrafish that enables in vitro analysis. Zebrafish OPCs are robust, can easily be purified with high viability and taken into cell culture. This method enables to examine why zebrafish OPCs remyelinate better than their mammalian counterparts, identify cell intrinsic responses, which could lead to pro-proliferating or pro-differentiating strategies, and to test small molecule approaches. In this methodology paper, we show efficient isolation of OPCs from adult zebrafish spinal cord and describe culture conditions that enable analysis up to 10 days in vitro. Finally, we demonstrate that zebrafish OPCs differentiate into Myelin Basic Protein (MBP)-expressing OLs when co-cultured with human motor neurons differentiated from induced pluripotent stem cells (iPSCs). This shows that the basic mechanisms of oligodendrocyte differentiation are conserved across species and that understanding the regulation of zebrafish OPCs can contribute to the development of new treatments to human diseases.
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Affiliation(s)
- Volker Kroehne
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany
| | - Vasiliki Tsata
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany
| | - Lara Marrone
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany
| | - Claudia Froeb
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany
| | - Susanne Reinhardt
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany.,Deep Sequencing Group, Center for Molecular and Cellular Bioengineering (CMCB), Biotechnologisches Zentrum (BIOTEC), Technische Universität DresdenDresden, Germany
| | - Anne Gompf
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany
| | - Andreas Dahl
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany.,Deep Sequencing Group, Center for Molecular and Cellular Bioengineering (CMCB), Biotechnologisches Zentrum (BIOTEC), Technische Universität DresdenDresden, Germany
| | - Jared Sterneckert
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany
| | - Michell M Reimer
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence, Technische Universität DresdenDresden, Germany
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Vijayanathan Y, Lim FT, Lim SM, Long CM, Tan MP, Majeed ABA, Ramasamy K. 6-OHDA-Lesioned Adult Zebrafish as a Useful Parkinson's Disease Model for Dopaminergic Neuroregeneration. Neurotox Res 2017; 32:496-508. [PMID: 28707266 DOI: 10.1007/s12640-017-9778-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 06/14/2017] [Accepted: 06/28/2017] [Indexed: 12/16/2022]
Abstract
Conventional mammalian models of neurodegeneration are often limited by futile axonogenesis with minimal functional recuperation of severed neurons. The emergence of zebrafish, a non-mammalian model with excellent neuroregenerative properties, may address these limitations. This study aimed to establish an adult zebrafish-based, neurotoxin-induced Parkinson's disease (PD) model and subsequently validate the regenerative capability of dopaminergic neurons (DpN). The DpN of adult male zebrafish (Danio rerio) were lesioned by microinjecting 6-hydroxydopamine (6-OHDA) neurotoxin (6.25, 12.5, 18.75, 25, 37.5, 50 and 100 mg/kg) into the ventral diencephalon (Dn). This was facilitated by an optimised protocol that utilised 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanineperchlorate (DiI) dye to precisely identify the injection site. Immunostaining was utilised to identify the number of tyrosine hydroxylase immunoreactive (TH-ir) DpN in brain regions of interest (i.e. olfactory bulb, telencephalon, preoptic area, posterior tuberculum and hypothalamus). Open tank video recordings were performed for locomotor studies. The Dn was accessed by setting the injection angle of the microinjection capillary to 60° and injection depth to 1200 μm (from the exposed brain surface). 6-OHDA (25 mg/kg) successfully ablated >85% of the Dn DpN (preoptic area, posterior tuberculum and hypothalamus) whilst maintaining a 100% survival. Locomotor analysis of 5-min recordings revealed that 6-OHDA-lesioned adult zebrafish were significantly (p < 0.0001) reduced in speed (cm/s) and distance travelled (cm). Lesioned zebrafish showed full recovery of Dn DpN 30 days post-lesion. This study had successfully developed a stable 6-OHDA-induced PD zebrafish model using a straightforward and reproducible approach. Thus, this developed teleost model poses exceptional potentials to study DpN regeneration.
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Affiliation(s)
- Yuganthini Vijayanathan
- Collaborative Drug Discovery Research (CDDR) Group, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), 42300, Puncak Alam, Selangor Darul Ehsan, Malaysia.,Division of Geriatric Medicine, Department of Medicine, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Fei Tieng Lim
- Collaborative Drug Discovery Research (CDDR) Group, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), 42300, Puncak Alam, Selangor Darul Ehsan, Malaysia
| | - Siong Meng Lim
- Collaborative Drug Discovery Research (CDDR) Group, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), 42300, Puncak Alam, Selangor Darul Ehsan, Malaysia
| | - Chiau Ming Long
- School of Pharmacy, KPJ Healthcare University College, 71800, Nilai, Negeri Sembilan, Malaysia
| | - Maw Pin Tan
- Division of Geriatric Medicine, Department of Medicine, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Abu Bakar Abdul Majeed
- Collaborative Drug Discovery Research (CDDR) Group, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), 42300, Puncak Alam, Selangor Darul Ehsan, Malaysia
| | - Kalavathy Ramasamy
- Collaborative Drug Discovery Research (CDDR) Group, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), 42300, Puncak Alam, Selangor Darul Ehsan, Malaysia.
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Ma L, Shen HF, Shen YQ, Schachner M. The Adhesion Molecule-Characteristic HNK-1 Carbohydrate Contributes to Functional Recovery After Spinal Cord Injury in Adult Zebrafish. Mol Neurobiol 2017; 54:3253-3263. [PMID: 27086029 DOI: 10.1007/s12035-016-9876-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 03/18/2016] [Indexed: 02/05/2023]
Abstract
The human natural killer cell antigen-1 (HNK-1) is functionally important in development, synaptic activity, and regeneration after injury in the nervous system of several mammalian species. It contains a sulfated glucuronic acid which is carried by neural adhesion molecules and expressed in nonmammalian species, including zebrafish, which, as opposed to mammals, spontaneously regenerate after injury in the adult. To evaluate HNK-1's role in recovery of function after spinal cord injury (SCI) of adult zebrafish, we assessed the effects of the two HNK-1 synthesizing enzymes, glucuronyl transferase and HNK-1 sulfotransferase. Expression of these two enzymes was increased at the messenger RNA (mRNA) level 11 days after injury in the brainstem nuclei that are capable of regrowth of severed axons, namely, the nucleus of medial longitudinal fascicle and intermediate reticular formation, but not at earlier time points after SCI. mRNA levels of glucuronyl transferase and sulfotransferase were increased in neurons, not only of these nuclei but also in the spinal cord caudal to the injury site at 11 days. Mauthner neurons which are not capable of regeneration did not show increased levels of enzyme mRNAs after injury. Reducing protein levels of the enzymes by application of anti-sense morpholinos resulted in reduction of locomotor recovery for glucuronyl transferase, but not for HNK-1 sulfotransferase. The combined results indicate that HNK-1 is upregulated in expression only in those neurons that are intrinsically capable of regeneration and contributes to regeneration after spinal cord injury in adult zebrafish in the absence of its sulfate moiety.
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Affiliation(s)
- Liping Ma
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854, USA
| | - Hui-Fan Shen
- Center for Neuroscience, Shantou University Medical College, 22 Xin Ling Road, Shantou, Guangdong, 515041, P.R. China
| | - Yan-Qin Shen
- Center for Neuroscience, Shantou University Medical College, 22 Xin Ling Road, Shantou, Guangdong, 515041, P.R. China
- Department of Basic Medicine, Jiangnan University Medical School, Wuxi, Jiangsu, P.R. China
| | - Melitta Schachner
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854, USA.
- Center for Neuroscience, Shantou University Medical College, 22 Xin Ling Road, Shantou, Guangdong, 515041, P.R. China.
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Learning to swim, again: Axon regeneration in fish. Exp Neurol 2017; 287:318-330. [DOI: 10.1016/j.expneurol.2016.02.022] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 02/25/2016] [Accepted: 02/27/2016] [Indexed: 01/10/2023]
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The Many Hats of Sonic Hedgehog Signaling in Nervous System Development and Disease. J Dev Biol 2016; 4:jdb4040035. [PMID: 29615598 PMCID: PMC5831807 DOI: 10.3390/jdb4040035] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 11/17/2016] [Accepted: 11/29/2016] [Indexed: 02/06/2023] Open
Abstract
Sonic hedgehog (Shh) signaling occurs concurrently with the many processes that constitute nervous system development. Although Shh is mostly known for its proliferative and morphogenic action through its effects on neural stem cells and progenitors, it also contributes to neuronal differentiation, axonal pathfinding and synapse formation and function. To participate in these diverse events, Shh signaling manifests differently depending on the maturational state of the responsive cell, on the other signaling pathways regulating neural cell function and the environmental cues that surround target cells. Shh signaling is particularly dynamic in the nervous system, ranging from canonical transcription-dependent, to non-canonical and localized to axonal growth cones. Here, we review the variety of Shh functions in the developing nervous system and their consequences for neurodevelopmental diseases and neural regeneration, with particular emphasis on the signaling mechanisms underlying Shh action.
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42
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Abstract
In all vertebrate species studied thus far, the adult central nervous system harbors neural stem cells that sustain constitutive neurogenesis, as well as latent neural progenitors that can be awakened in lesional contexts. In spite of this common theme, many species differ dramatically in their ability to recruit constitutive progenitors, to awaken latent progenitors, or to enhance or bias neural progenitor fate to achieve successful neuronal repair. This Review summarizes the striking similarities in the essential molecular and cellular properties of adult neural stem cells between different vertebrate species, both under physiological and reparative conditions. It also emphasizes the differences in the reparative process across evolution and how the study of non-mammalian models can provide insights into both basic neural stem cell properties and stimulatory cues shared between vertebrates, and subsequent neurogenic events, which are abortive under reparative conditions in mammals. Summary: This Review article provides a comparative view of neuronal repair across vertebrate species, with a particular focus on the molecular pathways that enable repair in some, but not all animals.
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Affiliation(s)
- Alessandro Alunni
- Paris-Saclay Institute for Neuroscience, CNRS UMR9197 - Université Paris-Sud, Université Paris-Saclay, Team Zebrafish Neurogenetics, Avenue de la Terrasse, Building 5, Gif-sur-Yvette F-91198, France
| | - Laure Bally-Cuif
- Paris-Saclay Institute for Neuroscience, CNRS UMR9197 - Université Paris-Sud, Université Paris-Saclay, Team Zebrafish Neurogenetics, Avenue de la Terrasse, Building 5, Gif-sur-Yvette F-91198, France
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43
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Ghosh S, Hui SP. Regeneration of Zebrafish CNS: Adult Neurogenesis. Neural Plast 2016; 2016:5815439. [PMID: 27382491 PMCID: PMC4921647 DOI: 10.1155/2016/5815439] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 04/18/2016] [Indexed: 12/13/2022] Open
Abstract
Regeneration in the animal kingdom is one of the most fascinating problems that have allowed scientists to address many issues of fundamental importance in basic biology. However, we came to know that the regenerative capability may vary across different species. Among vertebrates, fish and amphibians are capable of regenerating a variety of complex organs through epimorphosis. Zebrafish is an excellent animal model, which can repair several organs like damaged retina, severed spinal cord, injured brain and heart, and amputated fins. The focus of the present paper is on spinal cord regeneration in adult zebrafish. We intend to discuss our current understanding of the cellular and molecular mechanism(s) that allows formation of proliferating progenitors and controls neurogenesis, which involve changes in epigenetic and transcription programs. Unlike mammals, zebrafish retains radial glia, a nonneuronal cell type in their adult central nervous system. Injury induced proliferation involves radial glia which proliferate, transcribe embryonic genes, and can give rise to new neurons. Recent technological development of exquisite molecular tools in zebrafish, such as cell ablation, lineage analysis, and novel and substantial microarray, together with advancement in stem cell biology, allowed us to investigate how progenitor cells contribute to the generation of appropriate structures and various underlying mechanisms like reprogramming.
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Affiliation(s)
- Sukla Ghosh
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92 A. P. C. Road, Kolkata 700009, India
| | - Subhra Prakash Hui
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92 A. P. C. Road, Kolkata 700009, India
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Parker GC, Carruthers NJ, Gratsch T, Caruso JA, Stemmer PM. Proteomic profile of embryonic stem cells with low survival motor neuron protein is consistent with developmental dysfunction. J Neural Transm (Vienna) 2016; 124:13-23. [PMID: 27145767 DOI: 10.1007/s00702-016-1520-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 02/01/2016] [Indexed: 12/22/2022]
Abstract
Spinal muscular atrophy is an autosomal recessive motor neuron disease caused by a genetic defect carried by as many as one in 75 people. Unlike most neurological disorders, we know exactly what the genetic basis is of the disorder, but in spite of this, have little understanding of why the low levels of one protein, survival motor neuron protein, results in the specific progressive die back of only one cell type in the body, the motor neuron. Given the fact that all cells in the body of a patient with spinal muscular atrophy share the same low abundance of the protein throughout development, an appropriate approach is to ask how lower levels of survival motor neuron protein affects the proteome of embryonic stem cells prior to development. Convergent biostatistical analyses of a discovery proteomic analysis of these cells provide results that are consistent with the pathomechanistic fate of the developed motor neuron.
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Affiliation(s)
- Graham C Parker
- Carman and Ann Adam Department of Pediatrics, Wayne State University, Detroit, USA.
- iBio, 6135 Woodward Ave., Suite 2128 CURES H208, Detroit, MI, 48202, USA.
| | - Nicholas J Carruthers
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, USA
| | - Theresa Gratsch
- Carman and Ann Adam Department of Pediatrics, Wayne State University, Detroit, USA
| | - Joseph A Caruso
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, USA
| | - Paul M Stemmer
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, USA
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Ohnmacht J, Yang Y, Maurer GW, Barreiro-Iglesias A, Tsarouchas TM, Wehner D, Sieger D, Becker CG, Becker T. Spinal motor neurons are regenerated after mechanical lesion and genetic ablation in larval zebrafish. Development 2016; 143:1464-74. [PMID: 26965370 PMCID: PMC4986163 DOI: 10.1242/dev.129155] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 02/25/2016] [Indexed: 01/14/2023]
Abstract
In adult zebrafish, relatively quiescent progenitor cells show lesion-induced generation of motor neurons. Developmental motor neuron generation from the spinal motor neuron progenitor domain (pMN) sharply declines at 48 hours post-fertilisation (hpf). After that, mostly oligodendrocytes are generated from the same domain. We demonstrate here that within 48 h of a spinal lesion or specific genetic ablation of motor neurons at 72 hpf, the pMN domain reverts to motor neuron generation at the expense of oligodendrogenesis. By contrast, generation of dorsal Pax2-positive interneurons was not altered. Larval motor neuron regeneration can be boosted by dopaminergic drugs, similar to adult regeneration. We use larval lesions to show that pharmacological suppression of the cellular response of the innate immune system inhibits motor neuron regeneration. Hence, we have established a rapid larval regeneration paradigm. Either mechanical lesions or motor neuron ablation is sufficient to reveal a high degree of developmental flexibility of pMN progenitor cells. In addition, we show an important influence of the immune system on motor neuron regeneration from these progenitor cells.
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Affiliation(s)
- Jochen Ohnmacht
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Yujie Yang
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Gianna W Maurer
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Antón Barreiro-Iglesias
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Themistoklis M Tsarouchas
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Daniel Wehner
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Dirk Sieger
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Catherina G Becker
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Thomas Becker
- Centre for Neuroregeneration, The University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
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46
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Meda F, Gauron C, Rampon C, Teillon J, Volovitch M, Vriz S. Nerves Control Redox Levels in Mature Tissues Through Schwann Cells and Hedgehog Signaling. Antioxid Redox Signal 2016; 24:299-311. [PMID: 26442784 PMCID: PMC4761803 DOI: 10.1089/ars.2015.6380] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AIMS Recent advances in redox biology have emphasized the role of hydrogen peroxide (H2O2) in the modulation of signaling pathways and revealed that H2O2 plays a role in cellular remodeling in adults. Thus, an understanding of the mechanisms that control H2O2 levels in mature tissue would be of great interest. RESULTS We used a denervation strategy to demonstrate that sensory neurons are responsible for controlling H2O2 levels under normal conditions and after being lesioned. Moreover, we demonstrate that severed nerves respond to appendage amputation via the induction of Hedgehog signaling and that this signaling is responsible for H2O2 production in the wounded epidermis. Finally, we show that H2O2 and nerve growth are regulated via reciprocal action in adults. INNOVATION AND CONCLUSION These data support a new paradigm for the regulation of tissue homeostasis: H2O2 attracts nerves and nerves control H2O2 levels in a positive feedback loop. This finding suggests that the peripheral nerve redox environment could be a target for manipulating cell plasticity in adults.
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Affiliation(s)
- Francesca Meda
- 1 Centre Interdisciplinaire de Recherche en Biologie (CIRB) CNRS UMR 7241/INSERM U1050/Collège de France , Paris, France .,2 École Normale Supérieure, Institute of Biology at the Ecole Normale Supérieure (IBENS) , CNRS UMR8197, INSERM U1024, Paris, France .,3 PSL Research University , Paris, France
| | - Carole Gauron
- 1 Centre Interdisciplinaire de Recherche en Biologie (CIRB) CNRS UMR 7241/INSERM U1050/Collège de France , Paris, France .,3 PSL Research University , Paris, France
| | - Christine Rampon
- 1 Centre Interdisciplinaire de Recherche en Biologie (CIRB) CNRS UMR 7241/INSERM U1050/Collège de France , Paris, France .,3 PSL Research University , Paris, France .,4 Biology Department, Université Paris Diderot , Sorbonne Paris Cité, Paris Cedex 13, France
| | - Jérémie Teillon
- 1 Centre Interdisciplinaire de Recherche en Biologie (CIRB) CNRS UMR 7241/INSERM U1050/Collège de France , Paris, France .,3 PSL Research University , Paris, France
| | - Michel Volovitch
- 1 Centre Interdisciplinaire de Recherche en Biologie (CIRB) CNRS UMR 7241/INSERM U1050/Collège de France , Paris, France .,2 École Normale Supérieure, Institute of Biology at the Ecole Normale Supérieure (IBENS) , CNRS UMR8197, INSERM U1024, Paris, France .,3 PSL Research University , Paris, France
| | - Sophie Vriz
- 1 Centre Interdisciplinaire de Recherche en Biologie (CIRB) CNRS UMR 7241/INSERM U1050/Collège de France , Paris, France .,3 PSL Research University , Paris, France .,4 Biology Department, Université Paris Diderot , Sorbonne Paris Cité, Paris Cedex 13, France
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47
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Tena TC, Philipp M. Assessing Smoothened-mediated Hedgehog signaling in zebrafish. Methods Cell Biol 2015; 132:147-64. [PMID: 26928543 DOI: 10.1016/bs.mcb.2015.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Smoothened belongs to the class of atypical G protein-coupled receptors and serves as the transducing molecule in Hedgehog (Hh) signaling. Hh proteins comprise a family of secreted, cholesterol-modified ligands, which act both as morphogens and as signaling molecules. Binding of Hh proteins to their direct receptor, the transmembrane protein Patched-1, relieves Smoothened from tonal inhibition by Patched-1 and causes the translocation of Smoothened into the cilium. Here, the Hh signaling cascade is initiated and results in transcriptional activation of Hh target genes such as gli1 or patched-1. This induces a plethora of physiological outcomes including normal embryonic development, but also cancer, which is the reason why scientists aim to develop strategies to manipulate as well as monitor Smoothened-mediated Hh signaling. The zebrafish has emerged as a valuable tool for the assessment of Smoothened-mediated Hh signaling. In this chapter we thus describe how Smoothened-mediated Hh signaling can be monitored and also quantified using zebrafish embryos.
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Affiliation(s)
- Teresa Casar Tena
- Institute for Biochemistry and Molecular Biology, Ulm University, Ulm, Germany
| | - Melanie Philipp
- Institute for Biochemistry and Molecular Biology, Ulm University, Ulm, Germany
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48
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Hui SP, Nag TC, Ghosh S. Characterization of Proliferating Neural Progenitors after Spinal Cord Injury in Adult Zebrafish. PLoS One 2015; 10:e0143595. [PMID: 26630262 PMCID: PMC4667880 DOI: 10.1371/journal.pone.0143595] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 11/06/2015] [Indexed: 12/14/2022] Open
Abstract
Zebrafish can repair their injured brain and spinal cord after injury unlike adult mammalian central nervous system. Any injury to zebrafish spinal cord would lead to increased proliferation and neurogenesis. There are presences of proliferating progenitors from which both neuronal and glial loss can be reversed by appropriately generating new neurons and glia. We have demonstrated the presence of multiple progenitors, which are different types of proliferating populations like Sox2+ neural progenitor, A2B5+ astrocyte/ glial progenitor, NG2+ oligodendrocyte progenitor, radial glia and Schwann cell like progenitor. We analyzed the expression levels of two common markers of dedifferentiation like msx-b and vimentin during regeneration along with some of the pluripotency associated factors to explore the possible role of these two processes. Among the several key factors related to pluripotency, pou5f1 and sox2 are upregulated during regeneration and associated with activation of neural progenitor cells. Uncovering the molecular mechanism for endogenous regeneration of adult zebrafish spinal cord would give us more clues on important targets for future therapeutic approach in mammalian spinal cord repair and regeneration.
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Affiliation(s)
- Subhra Prakash Hui
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, A. P. C. Road, Kolkata—700009, India
| | - Tapas Chandra Nag
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi- 110029, India
| | - Sukla Ghosh
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, A. P. C. Road, Kolkata—700009, India
- * E-mail:
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49
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Mysiak KS, Barreiro‐Iglesias A, Reimer MM, Scott AL, Yang Y, Becker T, Becker CG. ISDN2014_0175: Serotonin promotes motor neuron development and adult regeneration in zebrafish. Int J Dev Neurosci 2015. [DOI: 10.1016/j.ijdevneu.2015.04.144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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50
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Barreiro-Iglesias A, Mysiak KS, Scott AL, Reimer MM, Yang Y, Becker CG, Becker T. Serotonin Promotes Development and Regeneration of Spinal Motor Neurons in Zebrafish. Cell Rep 2015; 13:924-32. [PMID: 26565906 PMCID: PMC4635313 DOI: 10.1016/j.celrep.2015.09.050] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 06/13/2015] [Accepted: 09/17/2015] [Indexed: 12/26/2022] Open
Abstract
In contrast to mammals, zebrafish regenerate spinal motor neurons. During regeneration, developmental signals are re-deployed. Here, we show that, during development, diffuse serotonin promotes spinal motor neuron generation from pMN progenitor cells, leaving interneuron numbers unchanged. Pharmacological manipulations and receptor knockdown indicate that serotonin acts at least in part via 5-HT1A receptors. In adults, serotonin is supplied to the spinal cord mainly (90%) by descending axons from the brain. After a spinal lesion, serotonergic axons degenerate caudal to the lesion but sprout rostral to it. Toxin-mediated ablation of serotonergic axons also rostral to the lesion impaired regeneration of motor neurons only there. Conversely, intraperitoneal serotonin injections doubled numbers of new motor neurons and proliferating pMN-like progenitors caudal to the lesion. Regeneration of spinal-intrinsic serotonergic interneurons was unaltered by these manipulations. Hence, serotonin selectively promotes the development and adult regeneration of motor neurons in zebrafish.
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Affiliation(s)
- Antón Barreiro-Iglesias
- Centre for Neuroregeneration, Edinburgh Medical School, Biomedical Sciences, The Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Karolina S Mysiak
- Centre for Neuroregeneration, Edinburgh Medical School, Biomedical Sciences, The Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Angela L Scott
- Centre for Neuroregeneration, Edinburgh Medical School, Biomedical Sciences, The Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Michell M Reimer
- Centre for Neuroregeneration, Edinburgh Medical School, Biomedical Sciences, The Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, UK; Technische Universität Dresden, DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence at the TU Dresden, Fetscherstraße 105, 01307 Dresden, Germany
| | - Yujie Yang
- Centre for Neuroregeneration, Edinburgh Medical School, Biomedical Sciences, The Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Catherina G Becker
- Centre for Neuroregeneration, Edinburgh Medical School, Biomedical Sciences, The Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, UK; Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh EH16 4SB, UK.
| | - Thomas Becker
- Centre for Neuroregeneration, Edinburgh Medical School, Biomedical Sciences, The Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, UK; Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh EH16 4SB, UK.
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