1
|
Wang X, Wang W, Dai Z. The Neural Control Mechanisms of Gekkonid Adhesion Locomotion: The Effect of Spinal Cord Lesions. Biomimetics (Basel) 2022; 7:biomimetics7030098. [PMID: 35892368 PMCID: PMC9332208 DOI: 10.3390/biomimetics7030098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 11/16/2022] Open
Abstract
Objective: the role of the supraspinal system in the neural control mechanisms of adhesion locomotor pattern formation was studied in lizard Gekko gecko. Methods: the locomotor performance and adaptation of the chronically lesioned Gekko gecko was documented before and after either partial or complete spinal lesions. They were filmed moving on a flat and smooth platform that was inclined at 0°, ±45°, and ±90°, as well as the horizontal mats and the vertical oak background board in the terraria, to evaluate locomotor functional recovery. The geckos were also tested on the platform by two half and nose-up or -down rotations in steps of 15° throughout 180° to investigate the recovery of the ability to respond dynamically to external perturbations. Results: after relatively small lesions of a hemisection, the locomotor performance was largely indistinguishable from that before and after a sham operation. During the initial period of recovery after the largest lesions of a dorsal or a ventral hemisection within 1 wk, the geckos behaved essentially as the complete spinal geckos, while permanent deficits in locomotor performance remained and did not decrease afterwards for ≥6 mth. Conclusions: by analyzing the correlation among locomotor performances, and between locomotor performances and spinal cord lesions, we suggest that the dorsal spinal pathways and ventral spinal pathways participate, respectively, in the control of the limb coupling, and in the deployment and the detachment of the adhesive apparatus. The present study will provide certain neurobiological guidance for the design of bio-robots, as well as sprawling robots inspired by the geckos.
Collapse
|
2
|
He B, Sun C, Li H, Yang T, Song H, Wang Y, Wang Y. Primary culture of adult cortical neurons from reptile Gekko japonicus. J Anat 2021; 239:913-919. [PMID: 34047374 PMCID: PMC8450464 DOI: 10.1111/joa.13461] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 05/06/2021] [Accepted: 05/07/2021] [Indexed: 01/26/2023] Open
Abstract
Adult neurons of several reptiles still retain the ability of axonal regeneration in contrast to the low intrinsic regenerative capacity of those in the central nervous system (CNS) in mammals. This feature of the reptilian neurons has provided a perfect model for elucidating the regenerative mechanism lost in the mammalian counterparts. However, little information is available on the primary culture method of adult reptilian neurons, which greatly limits their valuable applications. In the present study, we introduced a simple and easy method for the isolation, culture, and identification of neurons from the cerebral cortex using the adult geckos. The cultured cells were further identified by immunofluorescence using antibodies against neuron-specific markers β-Ⅲ-tubulin and NeuN. The cortical neurons from adult gecko displayed spindle-shaped, bipolar, or multipolar morphology with a plump soma. This primary culture method for adult reptilian neurons will be beneficial for comparative studies of neuronal biology in various vertebrates.
Collapse
Affiliation(s)
- Bingqiang He
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Chunshuai Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Hui Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Ting Yang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Honghua Song
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Yongjun Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Yingjie Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| |
Collapse
|
3
|
Alibardi L. Growth associated protein 43 and neurofilament immunolabeling in the transected lumbar spinal cord of lizard indicates limited axonal regeneration. Neural Regen Res 2021; 17:1034-1041. [PMID: 34558530 PMCID: PMC8552833 DOI: 10.4103/1673-5374.324850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Previous cytological studies on the transected lumbar spinal cord of lizards have shown the presence of differentiating glial cells, few neurons and axons in the bridge region between the proximal and distal stumps of the spinal cord in some cases. A limited number of axons (20–50) can cross the bridge and re-connect the caudal stump of the spinal cord with small neurons located in the rostral stump of the spinal cord. This axonal regeneration appears to be related to the recovery of hind-limb movements after initial paralysis. The present study extends previous studies and shows that after transection of the lumbar spinal cord in lizards, a glial-connective tissue bridge that reconnects the rostral and caudal stumps of the interrupted spinal cord is formed at 11–34 days post-injury. Following an initial paralysis some recovery of hindlimb movements occurs within 1–3 months post-injury. Immunohistochemical and ultrastructural analysis for a growth associated protein 43 (GAP-43) of 48–50 kDa shows that sparse GAP-43 positive axons are present in the proximal stump of the spinal cord but their number decreased in the bridge at 11–34 days post-transection. Few immunolabeled axons with a neurofilament protein of 200–220 kDa were seen in the bridge at 11–22 days post-transection but their number increased at 34 days and 3 months post-amputation in lizards that have recovered some hindlimb movements. Numerous neurons in the rostral and caudal stumps of the spinal cord were also labeled for GAP43, a cytoplasmic protein that is trans-located into their axonal growth cones. This indicates that GAP-43 biosynthesis is related to axonal regeneration and sprouting from neurons that were damaged by the transection. Taken together, previous studies that utilized tract-tracing technique to label the present observations confirm that a limited axonal re-connection of the transected spinal cord occurs 1–3 months post-injury in lizards. The few regenerating-sprouting axons within the bridge reconnect the caudal with the rostral stumps of the spinal cord, and likely contribute to activate the neural circuits that sustain the limited but important recovery of hind-limb movements after initial paralysis. The surgical procedures utilized in the study followed the regulations on animal care and experimental procedures under the Italian Guidelines (art. 5, DL 116/92).
Collapse
Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab Padova and Department of Biology, University of Bologna, Bologna, Italy
| |
Collapse
|
4
|
Regeneration in Reptiles Generally and the New Zealand Tuatara in Particular as a Model to Analyse Organ Regrowth in Amniotes: A Review. J Dev Biol 2021; 9:jdb9030036. [PMID: 34564085 PMCID: PMC8482124 DOI: 10.3390/jdb9030036] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 08/26/2021] [Accepted: 08/27/2021] [Indexed: 01/18/2023] Open
Abstract
The ability to repair injuries among reptiles, i.e., ectothermic amniotes, is similar to that of mammals with some noteworthy exceptions. While large wounds in turtles and crocodilians are repaired through scarring, the reparative capacity involving the tail derives from a combined process of wound healing and somatic growth, the latter being continuous in reptiles. When the tail is injured in juvenile crocodilians, turtles and tortoises as well as the tuatara (Rhynchocephalia: Sphenodon punctatus, Gray 1842), the wound is repaired in these reptiles and some muscle and connective tissue and large amounts of cartilage are regenerated during normal growth. This process, here indicated as “regengrow”, can take years to produce tails with similar lengths of the originals and results in only apparently regenerated replacements. These new tails contain a cartilaginous axis and very small (turtle and crocodilians) to substantial (e.g., in tuatara) muscle mass, while most of the tail is formed by an irregular dense connective tissue containing numerous fat cells and sparse nerves. Tail regengrow in the tuatara is a long process that initially resembles that of lizards (the latter being part of the sister group Squamata within the Lepidosauria) with the formation of an axial ependymal tube isolated within a cartilaginous cylinder and surrounded by an irregular fat-rich connective tissue, some muscle bundles, and neogenic scales. Cell proliferation is active in the apical regenerative blastema, but much reduced cell proliferation continues in older regenerated tails, where it occurs mostly in the axial cartilage and scale epidermis of the new tail, but less commonly in the regenerated spinal cord, muscles, and connective tissues. The higher tissue regeneration of Sphenodon and other lepidosaurians provides useful information for attempts to improve organ regeneration in endothermic amniotes.
Collapse
|
5
|
Haspel G, Severi KE, Fauci LJ, Cohen N, Tytell ED, Morgan JR. Resilience of neural networks for locomotion. J Physiol 2021; 599:3825-3840. [PMID: 34187088 DOI: 10.1113/jp279214] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 06/22/2021] [Indexed: 01/15/2023] Open
Abstract
Locomotion is an essential behaviour for the survival of all animals. The neural circuitry underlying locomotion is therefore highly robust to a wide variety of perturbations, including injury and abrupt changes in the environment. In the short term, fault tolerance in neural networks allows locomotion to persist immediately after mild to moderate injury. In the longer term, in many invertebrates and vertebrates, neural reorganization including anatomical regeneration can restore locomotion after severe perturbations that initially caused paralysis. Despite decades of research, very little is known about the mechanisms underlying locomotor resilience at the level of the underlying neural circuits and coordination of central pattern generators (CPGs). Undulatory locomotion is an ideal behaviour for exploring principles of circuit organization, neural control and resilience of locomotion, offering a number of unique advantages including experimental accessibility and modelling tractability. In comparing three well-characterized undulatory swimmers, lampreys, larval zebrafish and Caenorhabditis elegans, we find similarities in the manifestation of locomotor resilience. To advance our understanding, we propose a comparative approach, integrating experimental and modelling studies, that will allow the field to begin identifying shared and distinct solutions for overcoming perturbations to persist in orchestrating this essential behaviour.
Collapse
Affiliation(s)
- Gal Haspel
- Federated Department of Biological Sciences, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Kristen E Severi
- Federated Department of Biological Sciences, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Lisa J Fauci
- Department of Mathematics, Tulane University, New Orleans, LA, 70118, USA
| | - Netta Cohen
- School of Computing, University of Leeds, Leeds, LS2 9JT, UK
| | - Eric D Tytell
- Department of Biology, Tufts University, Medford, MA, 02155, USA
| | - Jennifer R Morgan
- The Eugene Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA, 02543, USA
| |
Collapse
|
6
|
Du N, Li H, Sun C, He B, Yang T, Song H, Wang Y, Wang Y. Adult astrocytes from reptiles are resistant to proinflammatory activation via sustaining Vav1 expression. J Biol Chem 2021; 296:100527. [PMID: 33705794 PMCID: PMC8065226 DOI: 10.1016/j.jbc.2021.100527] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 02/25/2021] [Accepted: 03/05/2021] [Indexed: 11/17/2022] Open
Abstract
Adult mammalian astrocytes are sensitive to inflammatory stimuli in the context of neuropathology or mechanical injury, thereby affecting functional outcomes of the central nervous system (CNS). In contrast, glial cells residing in the spinal cord of regenerative vertebrates exhibit a weak astroglial reaction similar to those of mammals in embryonic stages. Macrophage migration inhibitory factor (MIF) participates in multiple neurological disorders by activation of glial and immune cells. However, the mechanism of astrocytes from regenerative species, such as gecko astrocytes (gAS), in resistance to MIF-mediated inflammation in the severed cords remains unclear. Here, we compared neural stem cell markers among gAS, as well as adult (rAS) and embryonic (eAS) rat astrocytes. We observed that gAS retained an immature phenotype resembling rat eAS. Proinflammatory activation of gAS with gecko (gMIF) or rat (rMIF) recombinant protein was unable to induce the production of inflammatory cytokines, despite its interaction with membrane CD74 receptor. Using cross-species screening of inflammation-related mediators from models of gMIF- and rMIF-induced gAS and rAS, we identified Vav1 as a key regulator in suppressing the inflammatory activation of gAS. The gAS with Vav1 deficiency displayed significantly restored sensitivity to inflammatory stimuli. Meanwhile, gMIF acts to promote the migration of gAS through regulation of CXCL8 following cord lesion. Taken together, our results suggest that Vav1 contributes to the regulation of astrocyte-mediated inflammation, which might be beneficial for the therapeutic development of neurological diseases.
Collapse
Affiliation(s)
- Nan Du
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, PR China
| | - Hui Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, PR China
| | - Chunshuai Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, PR China
| | - Bingqiang He
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, PR China
| | - Ting Yang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, PR China
| | - Honghua Song
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, PR China
| | - Yingjie Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, PR China.
| | - Yongjun Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, PR China.
| |
Collapse
|
7
|
Alibardi L. NOGO-A immunolabeling is present in glial cells and some neurons of the recovering lumbar spinal cord in lizards. J Morphol 2020; 281:1260-1270. [PMID: 32770765 DOI: 10.1002/jmor.21245] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/07/2020] [Accepted: 07/19/2020] [Indexed: 12/13/2022]
Abstract
The transected lumbar spinal cord of lizards was studied for its ability to recover after paralysis. At 34 days post-lesion about 50% of lizards were capable of walking with a limited coordination, likely due to the regeneration of few connecting axons crossing the transection site of the spinal cord. This region, indicated as "bridge", contains glial cells among which oligodendrocytes and their elongation that are immunolabeled for NOGO-A. A main reactive protein band occurs at 100-110 kDa but a weaker band is also observed around 240 kDa, suggesting fragmentation of the native protein due to extraction or to physiological processing of the original protein. Most of the cytoplasmic immunolabeling observed in oligodendrocytes is associated with vesicles of the endoplasmic reticulum. Also, the nucleus is labeled in some oligodendrocytes that are myelinating sparse axons observed within the bridge at 22-34 days post-transection. This suggests that axonal regeneration is present within the bridge region. Immunolabeling for NOGO-A shows that the protein is also present in numerous reactive neurons, in particular motor-neurons localized in the proximal stump of the transected spinal cord. Ultrastructural immunolocalization suggests that NOGO is synthesized in the ribosomes of these neurons and becomes associated with the cisternae of the endoplasmic reticulum, probably following a secretory pathway addressed toward the axon. The present observations suggest that, like for the regenerating spinal cord of fish and amphibians, also in lizard NOGO-A is present in reactive neurons and appears associated to axonal regeneration and myelination.
Collapse
Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab Padova and Department of Biology, University of Bologna, Bologna, Italy
| |
Collapse
|
8
|
Belrose JL, Prasad A, Sammons MA, Gibbs KM, Szaro BG. Comparative gene expression profiling between optic nerve and spinal cord injury in Xenopus laevis reveals a core set of genes inherent in successful regeneration of vertebrate central nervous system axons. BMC Genomics 2020; 21:540. [PMID: 32758133 PMCID: PMC7430912 DOI: 10.1186/s12864-020-06954-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 07/27/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The South African claw-toed frog, Xenopus laevis, is uniquely suited for studying differences between regenerative and non-regenerative responses to CNS injury within the same organism, because some CNS neurons (e.g., retinal ganglion cells after optic nerve crush (ONC)) regenerate axons throughout life, whereas others (e.g., hindbrain neurons after spinal cord injury (SCI)) lose this capacity as tadpoles metamorphose into frogs. Tissues from these CNS regions (frog ONC eye, tadpole SCI hindbrain, frog SCI hindbrain) were used in a three-way RNA-seq study of axotomized CNS axons to identify potential core gene expression programs for successful CNS axon regeneration. RESULTS Despite tissue-specific changes in expression dominating the injury responses of each tissue, injury-induced changes in gene expression were nonetheless shared between the two axon-regenerative CNS regions that were not shared with the non-regenerative region. These included similar temporal patterns of gene expression and over 300 injury-responsive genes. Many of these genes and their associated cellular functions had previously been associated with injury responses of multiple tissues, both neural and non-neural, from different species, thereby demonstrating deep phylogenetically conserved commonalities between successful CNS axon regeneration and tissue regeneration in general. Further analyses implicated the KEGG adipocytokine signaling pathway, which links leptin with metabolic and gene regulatory pathways, and a novel gene regulatory network with genes regulating chromatin accessibility at its core, as important hubs in the larger network of injury response genes involved in successful CNS axon regeneration. CONCLUSIONS This study identifies deep, phylogenetically conserved commonalities between CNS axon regeneration and other examples of successful tissue regeneration and provides new targets for studying the molecular underpinnings of successful CNS axon regeneration, as well as a guide for distinguishing pro-regenerative injury-induced changes in gene expression from detrimental ones in mammals.
Collapse
Affiliation(s)
- Jamie L Belrose
- Department of Biological Sciences, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY, 12222, USA
- Center for Neuroscience Research, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY, 12222, USA
| | - Aparna Prasad
- Department of Biological Sciences, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY, 12222, USA
- Center for Neuroscience Research, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY, 12222, USA
| | - Morgan A Sammons
- Department of Biological Sciences, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY, 12222, USA
| | - Kurt M Gibbs
- Department of Biology and Chemistry, Morehead State University, Morehead, KY, 40351, USA
| | - Ben G Szaro
- Department of Biological Sciences, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY, 12222, USA.
- Center for Neuroscience Research, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY, 12222, USA.
| |
Collapse
|
9
|
Cox GK, Gillis TE. Surviving anoxia: the maintenance of energy production and tissue integrity during anoxia and reoxygenation. J Exp Biol 2020; 223:223/13/jeb207613. [DOI: 10.1242/jeb.207613] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
ABSTRACT
The development of anoxia within tissues represents a significant challenge to most animals because of the decreased capacity for aerobic ATP production, the associated loss of essential cellular functions and the potential for detrimental tissue oxidation upon reoxygenation. Despite these challenges, there are many animals from multiple phyla that routinely experience anoxia and can fully recover. In this Review, we integrate knowledge gained from studies of anoxia-tolerant species across many animal taxa. We primarily focus on strategies used to reduce energy requirements, minimize the consequences of anaerobic ATP production and reduce the adverse effects of reactive oxygen species, which are responsible for tissue damage with reoxygenation. We aim to identify common strategies, as well as novel solutions, to the challenges of anoxia exposure. This Review chronologically examines the challenges faced by animals as they enter anoxia, as they attempt to maintain physiological function during prolonged anoxic exposure and, finally, as they emerge from anoxia. The capacity of animals to survive anoxia is also considered in relation to the increasing prevalence of anoxic zones within marine and freshwater environments, and the need to understand what limits survival.
Collapse
Affiliation(s)
- Georgina K. Cox
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Todd E. Gillis
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada, N1G 2W1
| |
Collapse
|
10
|
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: 29] [Impact Index Per Article: 7.3] [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.
Collapse
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
| |
Collapse
|
11
|
ASSESSMENT OF RESIDUAL VASCULARIZATION OF THE LIMB AS A PROGNOSTIC FACTOR TO AVOID SEA TURTLE FLIPPER AMPUTATION. J Wildl Dis 2020. [DOI: 10.7589/2019-02-039] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
12
|
Alibardi L. Observations on the recovering lumbar spinal cord of lizards show multiple origins of the cells forming the bridge region including immune cells. J Morphol 2019; 281:95-109. [DOI: 10.1002/jmor.21082] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/21/2019] [Accepted: 10/29/2019] [Indexed: 12/22/2022]
Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab Padova and University of Bologna Bologna Italy
| |
Collapse
|
13
|
Alibardi L. Tail regeneration in Lepidosauria as an exception to the generalized lack of organ regeneration in amniotes. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2019; 336:145-164. [PMID: 31532061 DOI: 10.1002/jez.b.22901] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 07/14/2019] [Accepted: 08/08/2019] [Indexed: 02/06/2023]
Abstract
The present review hypothesizes that during the transition from water to land, amniotes lost part of the genetic program for metamorphosis utilized in larvae of their amphibian ancestors, a program that in extant fish and amphibians allows organ regeneration. The direct development of amniotes, with their growth from embryos to adults, occurred with the elimination of larval stages, increases the efficiency of immune responses and the complexity of nervous circuits. In amniotes, T-cells and macrophages likely eliminate embryonic-larval antigens that are replaced with the definitive antigens of adult organs. Among lepidosaurians numerous lizard families during the Permian and Triassic evolved the process of tail autotomy to escape predation, followed by tail regeneration. Autotomy limits inflammation allowing the formation of a regenerative blastema rich in the immunosuppressant and hygroscopic hyaluronic acid. Expression loss of developmental genes for metamorphosis and segmentation in addition to an effective immune system, determined an imperfect regeneration of the tail. Genes involved in somitogenesis were likely lost or are inactivated and the axial skeleton and muscles of the original tail are replaced with a nonsegmented cartilaginous tube and segmental myotomes. Lack of neural genes, negative influence of immune system, and isolation of the regenerating spinal cord within the cartilaginous tube impede the production of nerve and glial cells, and a stratified spinal cord with ganglia. Tissue and organ regeneration in other body regions of lizards and other reptiles is relatively limited, like in the other amniotes, although the cartilage shows a higher regenerative capability than in mammals.
Collapse
Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab Padova and Department of Biology, University of Bologna, Bologna, Italy
| |
Collapse
|
14
|
Liu S, Chen Z. Employing Endogenous NSCs to Promote Recovery of Spinal Cord Injury. Stem Cells Int 2019; 2019:1958631. [PMID: 31191666 PMCID: PMC6525819 DOI: 10.1155/2019/1958631] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/07/2019] [Indexed: 12/15/2022] Open
Abstract
Endogenous neural stem cells (NSCs) exist in the central canal of mammalian spinal cords. Under normal conditions, these NSCs remain quiescent and express FoxJ1. After spinal cord injury (SCI), the endogenous NSCs of a heterogeneous nature are activated and proliferate and migrate towards the lesion site and mainly differentiate into astrocytes to repair the injured tissue. In vitro, spinal cord NSCs are multipotent and can differentiate into neurons, astrocytes, and oligodendrocytes. The altered microenvironments after SCI play key roles on the fate determination of activated NSCs, especially on the neuronal specification potential. Studies show that the activated spinal cord NSCs can generate interneurons when transplanted into the adult hippocampus. In addition, the spinal cord NSCs exhibit low immunogenicity in a transplantation context, thus implicating a promising therapeutic potential on SCI recovery. Here, we summarize the characteristics of spinal cord NSCs, especially their properties after injury. With a better understanding of endogenous NSCs under normal and SCI conditions, we may be able to employ endogenous NSCs for SCI repair in the future.
Collapse
Affiliation(s)
- Sumei Liu
- Cell Therapy Center, Beijing Institute of Geriatrics, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
- Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing 100053, China
| | - Zhiguo Chen
- Cell Therapy Center, Beijing Institute of Geriatrics, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
- Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing 100053, China
- Center of Neural Injury and Repair, Beijing Institute for Brain Disorders, Beijing 100069, China
- Center of Parkinson's Disease, Beijing Institute for Brain Disorders, Beijing 100069, China
| |
Collapse
|
15
|
Investigating Nrg1 Signaling in the Regenerating Axolotl Spinal Cord Using Multiplexed FISH. Dev Neurobiol 2019; 79:453-467. [DOI: 10.1002/dneu.22670] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 01/24/2019] [Accepted: 02/16/2019] [Indexed: 02/02/2023]
|
16
|
Freitas PD, Yandulskaya AS, Monaghan JR. Spinal Cord Regeneration in Amphibians: A Historical Perspective. Dev Neurobiol 2019; 79:437-452. [PMID: 30725532 DOI: 10.1002/dneu.22669] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 01/22/2019] [Accepted: 01/25/2019] [Indexed: 12/11/2022]
Abstract
In some vertebrates, a grave injury to the central nervous system (CNS) results in functional restoration, rather than in permanent incapacitation. Understanding how these animals mount a regenerative response by activating resident CNS stem cell populations is of critical importance in regenerative biology. Amphibians are of a particular interest in the field because the regenerative ability is present throughout life in urodele species, but in anuran species it is lost during development. Studying amphibians, who transition from a regenerative to a nonregenerative state, could give insight into the loss of ability to recover from CNS damage in mammals. Here, we highlight the current knowledge of spinal cord regeneration across vertebrates and identify commonalities and differences in spinal cord regeneration between amphibians.
Collapse
Affiliation(s)
- Polina D Freitas
- Department of Biology, Northeastern University, 360 Huntington Ave., 134 Mugar Hall, Boston, Massachusetts, 02115
| | - Anastasia S Yandulskaya
- Department of Biology, Northeastern University, 360 Huntington Ave., 134 Mugar Hall, Boston, Massachusetts, 02115
| | - James R Monaghan
- Department of Biology, Northeastern University, 360 Huntington Ave., 134 Mugar Hall, Boston, Massachusetts, 02115
| |
Collapse
|
17
|
Neumann B, Linton C, Giordano-Santini R, Hilliard MA. Axonal fusion: An alternative and efficient mechanism of nerve repair. Prog Neurobiol 2018; 173:88-101. [PMID: 30500382 DOI: 10.1016/j.pneurobio.2018.11.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 11/22/2018] [Accepted: 11/26/2018] [Indexed: 02/07/2023]
Abstract
Injuries to the nervous system can cause lifelong morbidity due to the disconnect that occurs between nerve cells and their cellular targets. Re-establishing these lost connections is the ultimate goal of endogenous regenerative mechanisms, as well as those induced by exogenous manipulations in a laboratory or clinical setting. Reconnection between severed neuronal fibers occurs spontaneously in some invertebrate species and can be induced in mammalian systems. This process, known as axonal fusion, represents a highly efficient means of repair after injury. Recent progress has greatly enhanced our understanding of the molecular control of axonal fusion, demonstrating that the machinery required for the engulfment of apoptotic cells is repurposed to mediate the reconnection between severed axon fragments, which are subsequently merged by fusogen proteins. Here, we review our current understanding of naturally occurring axonal fusion events, as well as those being ectopically produced with the aim of achieving better clinical outcomes.
Collapse
Affiliation(s)
- Brent Neumann
- Neuroscience Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne VIC 3800, Australia.
| | - Casey Linton
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Rosina Giordano-Santini
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Massimo A Hilliard
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
| |
Collapse
|
18
|
Spinal Cord Stem Cells In Their Microenvironment: The Ependyma as a Stem Cell Niche. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1041:55-79. [PMID: 29204829 DOI: 10.1007/978-3-319-69194-7_5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The ependyma of the spinal cord is currently proposed as a latent neural stem cell niche. This chapter discusses recent knowledge on the developmental origin and nature of the heterogeneous population of cells that compose this stem cell microenviroment, their diverse physiological properties and regulation. The chapter also reviews relevant data on the ependymal cells as a source of plasticity for spinal cord repair.
Collapse
|
19
|
Edwards-Faret G, Cebrián-Silla A, Méndez-Olivos EE, González-Pinto K, García-Verdugo JM, Larraín J. Cellular composition and organization of the spinal cord central canal during metamorphosis of the frog Xenopus laevis. J Comp Neurol 2018; 526:1712-1732. [PMID: 29603210 DOI: 10.1002/cne.24441] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 03/12/2018] [Accepted: 03/21/2018] [Indexed: 01/12/2023]
Abstract
Studying the cellular composition and morphological changes of cells lining the central canal during Xenopus laevis metamorphosis could contribute to understand postnatal development and spinal cord regeneration. Here we report the analysis of central canal cells at different stages during metamorphosis using immunofluorescence for protein markers expression, transmission and scanning electron microscopy and cell proliferation assays. The central canal was regionalized according to expression of glial markers, ultrastructure, and proliferation in dorsal, lateral, and ventral domains with differences between larvae and froglets. In regenerative larvae, all cell types were uniciliated, have a radial morphology, and elongated nuclei with lax chromatin, resembling radial glial cells. Important differences in cells of nonregenerative froglets were observed, although uniciliated cells were found, the most abundant cells had multicilia and revealed extensive changes in the maturation and differentiation state. The majority of dividing cells in larvae corresponded to uniciliated cells at dorsal and lateral domains in a cervical-lumbar gradient, correlating with undifferentiated features. Neurons contacting the lumen of the central canal were detected in both stages and revealed extensive changes in the maturation and differentiation state. However, in froglets a very low proportion of cells incorporate 5-ethynyl-2'-deoxyuridine (EdU), associated with the differentiated profile and with the increase of multiciliated cells. Our work showed progressive changes in the cell types lining the central canal of Xenopus laevis spinal cord which are correlated with the regenerative capacities.
Collapse
Affiliation(s)
- Gabriela Edwards-Faret
- Center for Aging and Regeneration, Faculty of Biological Sciences, P. Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile
| | - Arantxa Cebrián-Silla
- Laboratorio de Neurobiologia Comparada, Instituto Cavanilles, Universidad de Valencia, Valencia 46980, CIBERNED, Valencia, Spain
| | - Emilio E Méndez-Olivos
- Center for Aging and Regeneration, Faculty of Biological Sciences, P. Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile
| | - Karina González-Pinto
- Center for Aging and Regeneration, Faculty of Biological Sciences, P. Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile.,Universidad Arturo Prat del Estado de Chile, Iquique, Chile
| | - José Manuel García-Verdugo
- Laboratorio de Neurobiologia Comparada, Instituto Cavanilles, Universidad de Valencia, Valencia 46980, CIBERNED, Valencia, Spain
| | - Juan Larraín
- Center for Aging and Regeneration, Faculty of Biological Sciences, P. Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile
| |
Collapse
|
20
|
Fabbiani G, Rehermann MI, Aldecosea C, Trujillo-Cenóz O, Russo RE. Emergence of Serotonergic Neurons After Spinal Cord Injury in Turtles. Front Neural Circuits 2018; 12:20. [PMID: 29593503 PMCID: PMC5859367 DOI: 10.3389/fncir.2018.00020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 02/22/2018] [Indexed: 01/04/2023] Open
Abstract
Plasticity of neural circuits takes many forms and plays a fundamental role in regulating behavior to changing demands while maintaining stability. For example, during spinal cord development neurotransmitter identity in neurons is dynamically adjusted in response to changes in the activity of spinal networks. It is reasonable to speculate that this type of plasticity might occur also in mature spinal circuits in response to injury. Because serotonergic signaling has a central role in spinal cord functions, we hypothesized that spinal cord injury (SCI) in the fresh water turtle Trachemys scripta elegans may trigger homeostatic changes in serotonergic innervation. To test this possibility we performed immunohistochemistry for serotonin (5-HT) and key molecules involved in the determination of the serotonergic phenotype before and after SCI. We found that as expected, in the acute phase after injury the dense serotonergic innervation was strongly reduced. However, 30 days after SCI the population of serotonergic cells (5-HT+) increased in segments caudal to the lesion site. These cells expressed the neuronal marker HuC/D and the transcription factor Nkx6.1. The new serotonergic neurons did not incorporate the thymidine analog 5-bromo-2'-deoxyuridine (BrdU) and did not express the proliferating cell nuclear antigen (PCNA) indicating that novel serotonergic neurons were not newborn but post-mitotic cells that have changed their neurochemical identity. Switching towards a serotonergic neurotransmitter phenotype may be a spinal cord homeostatic mechanism to compensate for the loss of descending serotonergic neuromodulation, thereby helping the outstanding functional recovery displayed by turtles. The 5-HT1A receptor agonist (±)-8-Hydroxy-2-dipropylaminotetralin hydrobromide (8-OH-DPAT) blocked the increase in 5-HT+ cells suggesting 5-HT1A receptors may trigger the respecification process.
Collapse
Affiliation(s)
- Gabriela Fabbiani
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - María I Rehermann
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Carina Aldecosea
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Omar Trujillo-Cenóz
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Raúl E Russo
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| |
Collapse
|
21
|
Marichal N, Reali C, Rehermann MI, Trujillo-Cenóz O, Russo RE. Progenitors in the Ependyma of the Spinal Cord: A Potential Resource for Self-Repair After Injury. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1015:241-264. [DOI: 10.1007/978-3-319-62817-2_13] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
|
22
|
Valentin-Kahan A, García-Tejedor GB, Robello C, Trujillo-Cenóz O, Russo RE, Alvarez-Valin F. Gene Expression Profiling in the Injured Spinal Cord of Trachemys scripta elegans: An Amniote with Self-Repair Capabilities. Front Mol Neurosci 2017; 10:17. [PMID: 28223917 PMCID: PMC5293771 DOI: 10.3389/fnmol.2017.00017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 01/12/2017] [Indexed: 12/19/2022] Open
Abstract
Slider turtles are the only known amniotes with self-repair mechanisms of the spinal cord that lead to substantial functional recovery. Their strategic phylogenetic position makes them a relevant model to investigate the peculiar genetic programs that allow anatomical reconnection in some vertebrate groups but are absent in others. Here, we analyze the gene expression profile of the response to spinal cord injury (SCI) in the turtle Trachemys scripta elegans. We found that this response comprises more than 1000 genes affecting diverse functions: reaction to ischemic insult, extracellular matrix re-organization, cell proliferation and death, immune response, and inflammation. Genes related to synapses and cholesterol biosynthesis are down-regulated. The analysis of the evolutionary distribution of these genes shows that almost all are present in most vertebrates. Additionally, we failed to find genes that were exclusive of regenerating taxa. The comparison of expression patterns among species shows that the response to SCI in the turtle is more similar to that of mice and non-regenerative Xenopus than to Xenopus during its regenerative stage. This observation, along with the lack of conserved “regeneration genes” and the current accepted phylogenetic placement of turtles (sister group of crocodilians and birds), indicates that the ability of spinal cord self-repair of turtles does not represent the retention of an ancestral vertebrate character. Instead, our results suggest that turtles developed this capability from a non-regenerative ancestor (i.e., a lineage specific innovation) that was achieved by re-organizing gene expression patterns on an essentially non-regenerative genetic background. Among the genes activated by SCI exclusively in turtles, those related to anoxia tolerance, extracellular matrix remodeling, and axonal regrowth are good candidates to underlie functional recovery.
Collapse
Affiliation(s)
- Adrián Valentin-Kahan
- Department of Cellular and Molecular Neurophysiology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Gabriela B García-Tejedor
- Department of Cellular and Molecular Neurophysiology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Carlos Robello
- Molecular Biology Unit, Institut Pasteur de MontevideoMontevideo, Uruguay; Departamento de Bioquímica, Facultad de Medicina, Universidad de la RepublicaMontevideo, Uruguay
| | - Omar Trujillo-Cenóz
- Department of Cellular and Molecular Neurophysiology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Raúl E Russo
- Department of Cellular and Molecular Neurophysiology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Fernando Alvarez-Valin
- Sección Biomatemática, Unidad de Genómica Evolutiva, Facultad de Ciencias, Universidad de la República Montevideo, Uruguay
| |
Collapse
|
23
|
Axonal regeneration through the fibrous scar in lesioned goldfish spinal cord. Neuroscience 2015; 284:134-152. [DOI: 10.1016/j.neuroscience.2014.09.066] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 09/11/2014] [Accepted: 09/17/2014] [Indexed: 12/23/2022]
|
24
|
Observations on Lumbar Spinal Cord Recovery after Lesion in Lizards Indicates Regeneration of a Cellular and Fibrous Bridge Reconnecting the Injured Cord. J Dev Biol 2014. [DOI: 10.3390/jdb2040210] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
25
|
Bloom O. Non-mammalian model systems for studying neuro-immune interactions after spinal cord injury. Exp Neurol 2014; 258:130-40. [PMID: 25017894 PMCID: PMC4099969 DOI: 10.1016/j.expneurol.2013.12.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 12/24/2013] [Accepted: 12/26/2013] [Indexed: 01/09/2023]
Abstract
Mammals exhibit poor recovery after injury to the spinal cord, where the loss of neurons and neuronal connections can be functionally devastating. In contrast, it has long been appreciated that many non-mammalian vertebrate species exhibit significant spontaneous functional recovery after spinal cord injury (SCI). Identifying the biological responses that support an organism's inability or ability to recover function after SCI is an important scientific and medical question. While recent advances have been made in understanding the responses to SCI in mammals, we remain without an effective clinical therapy for SCI. A comparative biological approach to understanding responses to SCI in non-mammalian vertebrates will yield important insights into mechanisms that promote recovery after SCI. Presently, mechanistic studies aimed at elucidating responses, both intrinsic and extrinsic to neurons, that result in different regenerative capacities after SCI across vertebrates are just in their early stages. There are several inhibitory mechanisms proposed to impede recovery from SCI in mammals, including reactive gliosis and scarring, myelin associated proteins, and a suboptimal immune response. One hypothesis to explain the robust regenerative capacity of several non-mammalian vertebrates is a lack of some or all of these inhibitory signals. This review presents the current knowledge of immune responses to SCI in several non-mammalian species that achieve anatomical and functional recovery after SCI. This subject is of growing interest, as studies increasingly show both beneficial and detrimental roles of the immune response following SCI in mammals. A long-term goal of biomedical research in all experimental models of SCI is to understand how to promote functional recovery after SCI in humans. Therefore, understanding immune responses to SCI in non-mammalian vertebrates that achieve functional recovery spontaneously may identify novel strategies to modulate immune responses in less regenerative species and promote recovery after SCI.
Collapse
Affiliation(s)
- Ona Bloom
- The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA; The Hofstra North Shore-LIJ School of Medicine, Hempstead Turnpike, Hempstead, NY 11549, USA.
| |
Collapse
|
26
|
Alibardi L. Histochemical, Biochemical and Cell Biological aspects of tail regeneration in lizard, an amniote model for studies on tissue regeneration. ACTA ACUST UNITED AC 2014; 48:143-244. [DOI: 10.1016/j.proghi.2013.12.001] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
27
|
Trujillo-Cenóz O, Marichal N, Rehermann MI, Russo RE. The inner lining of the reptilian brain: A heterogeneous cellular mosaic. Glia 2013; 62:300-16. [DOI: 10.1002/glia.22607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 11/05/2013] [Accepted: 11/13/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Omar Trujillo-Cenóz
- Neurofisiología Celular y Molecular; Instituto de Investigaciones Biológicas Clemente Estable; Avenida Italia 3318 CP11600 Montevideo Uruguay
| | - Nicolás Marichal
- Neurofisiología Celular y Molecular; Instituto de Investigaciones Biológicas Clemente Estable; Avenida Italia 3318 CP11600 Montevideo Uruguay
| | - María Inés Rehermann
- Neurofisiología Celular y Molecular; Instituto de Investigaciones Biológicas Clemente Estable; Avenida Italia 3318 CP11600 Montevideo Uruguay
| | - Raúl E. Russo
- Neurofisiología Celular y Molecular; Instituto de Investigaciones Biológicas Clemente Estable; Avenida Italia 3318 CP11600 Montevideo Uruguay
| |
Collapse
|
28
|
Short hairpin RNA against PTEN enhances regenerative growth of corticospinal tract axons after spinal cord injury. J Neurosci 2013; 33:15350-61. [PMID: 24068802 DOI: 10.1523/jneurosci.2510-13.2013] [Citation(s) in RCA: 214] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Developing approaches to promote the regeneration of descending supraspinal axons represents an ideal strategy for rebuilding neuronal circuits to improve functional recovery after spinal cord injury (SCI). Our previous studies demonstrated that genetic deletion of phosphatase and tensin homolog (PTEN) in mouse corticospinal neurons reactivates their regenerative capacity, resulting in significant regeneration of corticospinal tract (CST) axons after SCI. However, it is unknown whether nongenetic methods of suppressing PTEN have similar effects and how regenerating axons interact with the extrinsic environment. Herein, we show that suppressing PTEN expression with short-hairpin RNA (shRNA) promotes the regeneration of injured CST axons, and these axons form anatomical synapses in appropriate areas of the cord caudal to the lesion. Importantly, this model of increased CST regrowth enables the analysis of extrinsic regulators of CST regeneration in vivo. We find that regenerating axons avoid dense clusters of fibroblasts and macrophages in the lesion, suggesting that these cell types might be key inhibitors of axon regeneration. Furthermore, most regenerating axons cross the lesion in association with astrocytes, indicating that these cells might be important for providing a permissive bridge for axon regeneration. Lineage analysis reveals that these bridge-forming astrocytes are not derived from ependymal stem cells within the spinal cord, suggesting that they are more likely derived from a subset of mature astrocytes. Overall, this study reveals insights into the critical extrinsic and intrinsic regulators of axon regeneration and establishes shRNA as a viable means to manipulate these regulators and translate findings into other mammalian models.
Collapse
|
29
|
Anatomical and electrophysiological plasticity of locomotor networks following spinal transection in the salamander. Neurosci Bull 2013; 29:467-76. [PMID: 23893431 DOI: 10.1007/s12264-013-1363-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 05/19/2013] [Indexed: 01/09/2023] Open
Abstract
Recovery of locomotor behavior following spinal cord injury can occur spontaneously in some vertebrates, such as fish, urodele amphibians, and certain reptiles. This review provides an overview of the current status of our knowledge on the anatomical and electrophysiological changes occurring within the spinal cord that lead to, or are associated with the re-expression of locomotion in spinally-transected salamanders. A better understanding of these processes will help to devise strategies for restoring locomotor function in mammals, including humans.
Collapse
|
30
|
Endogenous proliferation after spinal cord injury in animal models. Stem Cells Int 2012; 2012:387513. [PMID: 23316243 PMCID: PMC3539424 DOI: 10.1155/2012/387513] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 10/06/2012] [Accepted: 10/29/2012] [Indexed: 12/12/2022] Open
Abstract
Spinal cord injury (SCI) results in motor and sensory deficits, the severity of which depends on the level and extent of the injury. Animal models for SCI research include transection, contusion, and compression mouse models. In this paper we will discuss the endogenous stem cell response to SCI in animal models. All SCI animal models experience a similar peak of cell proliferation three days after injury; however, each specific type of injury promotes a specific and distinct stem cell response. For example, the transection model results in a strong and localized initial increase of proliferation, while in contusion and compression models, the initial level of proliferation is lower but encompasses the entire rostrocaudal extent of the spinal cord. All injury types result in an increased ependymal proliferation, but only in contusion and compression models is there a significant level of proliferation in the lateral regions of the spinal cord. Finally, the fate of newly generated cells varies from a mainly oligodendrocyte fate in contusion and compression to a mostly astrocyte fate in the transection model. Here we will discuss the potential of endogenous stem/progenitor cell manipulation as a therapeutic tool to treat SCI.
Collapse
|
31
|
García G, Libisch G, Trujillo-Cenóz O, Robello C, Russo RE. Modulation of gene expression during early stages of reconnection of the turtle spinal cord. J Neurochem 2012; 121:996-1006. [PMID: 22469052 DOI: 10.1111/j.1471-4159.2012.07750.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The spinal cord of the freshwater turtle Trachemys dorbignyi regenerates after complete transection (Rehermann et al. J. Comp. Neurol. 515, 2009, 197-214). This remarkable ability may be related to the persistence around the central canal (CC) of progenitors functionally clustered via connexin 43 (Cx43) that express brain lipid binding protein (BLBP) and the transcription factor Pax6 (Russo et al. J. Neurosci. 28, 2008, 8510-8516). Indeed, because BLBP+ cells appear in the bridge joining the rostral and caudal stumps, we speculated that progenitors contacting the central canal may play a key part in spinal cord regeneration. To test this hypothesis, we designed degenerated primers pairing conserved regions for key proteins synthesized in progenitors (BLBP, Cx43, and Pax6) and the neuronal protein HuB. Fragments of these proteins were amplified, cloned, and sequenced. Based on these sequences, we analyzed the changes in the expression levels using quantitative real-time RT-PCR with specific primers, comparing the injured spinal cord at different times after injury (4, 12, 20, and 60 days) with uninjured spinal cords. We found a transient, early increase of BLBP, Cx43 and HuB mRNA, with Pax6 remaining unchanged. These results suggest that the selected genes--active in progenitor cells--play an important part in early mechanisms of spinal cord regeneration.
Collapse
Affiliation(s)
- Gabriela García
- Neurofisiología Celular y Molecular. Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | | | | | | | | |
Collapse
|
32
|
Transforming growth factor α transforms astrocytes to a growth-supportive phenotype after spinal cord injury. J Neurosci 2011; 31:15173-87. [PMID: 22016551 DOI: 10.1523/jneurosci.3441-11.2011] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Astrocytes are both detrimental and beneficial for repair and recovery after spinal cord injury (SCI). These dynamic cells are primary contributors to the growth-inhibitory glial scar, yet they are also neuroprotective and can form growth-supportive bridges on which axons traverse. We have shown that intrathecal administration of transforming growth factor α (TGFα) to the contused mouse spinal cord can enhance astrocyte infiltration and axonal growth within the injury site, but the mechanisms of these effects are not well understood. The present studies demonstrate that the epidermal growth factor receptor (EGFR) is upregulated primarily by astrocytes and glial progenitors early after SCI. TGFα directly activates the EGFR on these cells in vitro, inducing their proliferation, migration, and transformation to a phenotype that supports robust neurite outgrowth. Overexpression of TGFα in vivo by intraparenchymal adeno-associated virus injection adjacent to the injury site enhances cell proliferation, alters astrocyte distribution, and facilitates increased axonal penetration at the rostral lesion border. To determine whether endogenous EGFR activation is required after injury, SCI was also performed on Velvet (C57BL/6J-Egfr(Vel)/J) mice, a mutant strain with defective EGFR activity. The affected mice exhibited malformed glial borders, larger lesions, and impaired recovery of function, indicating that intrinsic EGFR activation is necessary for neuroprotection and normal glial scar formation after SCI. By further stimulating precursor proliferation and modifying glial activation to promote a growth-permissive environment, controlled stimulation of EGFR at the lesion border may be considered in the context of future strategies to enhance endogenous cellular repair after injury.
Collapse
|
33
|
Barreiro-Iglesias A. 'Evorego': studying regeneration to understand evolution, the case of the serotonergic system. BRAIN, BEHAVIOR AND EVOLUTION 2011; 79:1-3. [PMID: 22142995 DOI: 10.1159/000334187] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Antón Barreiro-Iglesias
- Shriners Hospitals Pediatric Research Center, Center for Neural Repair and Rehabilitation, Temple University School of Medicine, Philadelphia, PA 19140, USA.
| |
Collapse
|
34
|
Martino G, Pluchino S, Bonfanti L, Schwartz M. Brain regeneration in physiology and pathology: the immune signature driving therapeutic plasticity of neural stem cells. Physiol Rev 2011; 91:1281-304. [PMID: 22013212 PMCID: PMC3552310 DOI: 10.1152/physrev.00032.2010] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Regenerative processes occurring under physiological (maintenance) and pathological (reparative) conditions are a fundamental part of life and vary greatly among different species, individuals, and tissues. Physiological regeneration occurs naturally as a consequence of normal cell erosion, or as an inevitable outcome of any biological process aiming at the restoration of homeostasis. Reparative regeneration occurs as a consequence of tissue damage. Although the central nervous system (CNS) has been considered for years as a "perennial" tissue, it has recently become clear that both physiological and reparative regeneration occur also within the CNS to sustain tissue homeostasis and repair. Proliferation and differentiation of neural stem/progenitor cells (NPCs) residing within the healthy CNS, or surviving injury, are considered crucial in sustaining these processes. Thus a large number of experimental stem cell-based transplantation systems for CNS repair have recently been established. The results suggest that transplanted NPCs promote tissue repair not only via cell replacement but also through their local contribution to changes in the diseased tissue milieu. This review focuses on the remarkable plasticity of endogenous and exogenous (transplanted) NPCs in promoting repair. Special attention will be given to the cross-talk existing between NPCs and CNS-resident microglia as well as CNS-infiltrating immune cells from the circulation, as a crucial event sustaining NPC-mediated neuroprotection. Finally, we will propose the concept of the context-dependent potency of transplanted NPCs (therapeutic plasticity) to exert multiple therapeutic actions, such as cell replacement, neurotrophic support, and immunomodulation, in CNS repair.
Collapse
Affiliation(s)
- Gianvito Martino
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy.
| | | | | | | |
Collapse
|
35
|
D'Amico LA, Boujard D, Coumailleau P. Proliferation, migration and differentiation in juvenile and adult Xenopus laevis brains. Brain Res 2011; 1405:31-48. [DOI: 10.1016/j.brainres.2011.06.032] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 06/10/2011] [Accepted: 06/11/2011] [Indexed: 11/25/2022]
|
36
|
Rehermann MI, Santiñaque FF, López-Carro B, Russo RE, Trujillo-Cenóz O. Cell proliferation and cytoarchitectural remodeling during spinal cord reconnection in the fresh-water turtle Trachemys dorbignyi. Cell Tissue Res 2011; 344:415-33. [PMID: 21574060 DOI: 10.1007/s00441-011-1173-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 04/11/2011] [Indexed: 01/22/2023]
Abstract
In fresh-water turtles, the bridge connecting the proximal and caudal stumps of transected spinal cords consists of regenerating axons running through a glial cellular matrix. To understand the process leading to the generation of the scaffold bridging the lesion, we analyzed the mitotic activity triggered by spinal injury in animals maintained alive for 20-30 days after spinal cord transection. Flow cytometry and bromodeoxyuridine (BrdU)-labeling experiments revealed a significant increment of cycling cells around the lesion epicenter. BrdU-tagged cells maintained a close association with regenerating axons. Most dividing cells expressed the brain lipid-binding protein (BLBP). Cells with BrdU-positive nuclei expressed glial fibrillary acidic protein. As spinal cord regeneration involves dynamic cell rearrangements, we explored the ultra-structure of the bridge and found cells with the aspect of immature oligodendrocytes forming an embryonic-like microenvironment. These cells supported and ensheathed regenerating axons that were recognized by immunocytological and electron-microscopical procedures. Since functional recovery depends on proper impulse transmission, we examined the anatomical axon-glia relationships near the lesion epicenter. Computer-assisted three-dimensional models revealed helical axon-glial junctions in which the intercellular space appeared to be reduced (5-7 nm). Serial-sectioning analysis revealed that fibril-containing processes provided myelinating axon sheaths. Thus, disruption of the ependymal layer elicits mitotic activity predominantly in radial glia expressing BLBP on the lateral aspects of the ependyma. These cycling cells seem to migrate and contribute to the bridge providing the main support and sheaths for regenerating axons.
Collapse
Affiliation(s)
- María Inés Rehermann
- Departamento de Neurofisiología Celular y Molecular, Avenida Italia 3318, Montevideo, Uruguay
| | | | | | | | | |
Collapse
|
37
|
Gibbs KM, Chittur SV, Szaro BG. Metamorphosis and the regenerative capacity of spinal cord axons in Xenopus laevis. Eur J Neurosci 2010; 33:9-25. [PMID: 21059114 DOI: 10.1111/j.1460-9568.2010.07477.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Throughout the vertebrate subphylum, the regenerative potential of central nervous system axons is greatest in embryonic stages and declines as development progresses. For example, Xenopus laevis can functionally recover from complete transection of the spinal cord as a tadpole but is unable to do so after metamorphosing into a frog. Neurons of the reticular formation and raphe nucleus are among those that regenerate axons most reliably in tadpole and that lose this ability after metamorphosis. To identify molecular factors associated with the success and failure of spinal cord axon regeneration, we pharmacologically manipulated thyroid hormone (TH) levels using methimazole or triiodothyronine, to either keep tadpoles in a permanently larval state or induce precocious metamorphosis, respectively. Following complete spinal cord transection, serotonergic axons crossed the lesion site and tadpole swimming ability was restored when metamorphosis was inhibited, but these events failed to occur when metamorphosis was prematurely induced. Thus, the metamorphic events controlled by TH led directly to the loss of regenerative potential. Microarray analysis identified changes in hindbrain gene expression that accompanied regeneration-permissive and -inhibitory conditions, including many genes in the permissive condition that have been previously associated with axon outgrowth and neuroprotection. These data demonstrate that changes in gene expression occur within regenerating neurons in response to axotomy under regeneration-permissive conditions in which normal development has been suspended, and they identify candidate genes for future studies of how central nervous system axons can successfully regenerate in some vertebrates.
Collapse
Affiliation(s)
- Kurt M Gibbs
- Department of Biological Sciences, University at Albany, State University of New York, Albany, NY 12222, USA
| | | | | |
Collapse
|
38
|
White RE, McTigue DM, Jakeman LB. Regional heterogeneity in astrocyte responses following contusive spinal cord injury in mice. J Comp Neurol 2010; 518:1370-90. [PMID: 20151365 PMCID: PMC2867111 DOI: 10.1002/cne.22282] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Astrocytes and their precursors respond to spinal cord injury (SCI) by proliferating, migrating, and altering phenotype. This contributes to glial scar formation at the lesion border and gliosis in spared gray and white matter. The present study was undertaken to evaluate astrocyte changes over time and determine when and where interventions might be targeted to alter the astrocyte response. Bromodeoxyuridine (BrdU) was administered to mice 3 days after SCI, and cells expressing BrdU and the astrocyte marker, glial fibrillary acidic protein (GFAP), were counted at 3, 7, and 49 days post-injury (DPI). BrdU-labeled cells accumulated at the lesion border by 7 DPI and approximately half of these expressed GFAP. In spared white matter, the total number of BrdU+ cells decreased, while the percentage of BrdU+ cells expressing GFAP increased at 49 DPI. Phenotypic changes were examined using the progenitor marker nestin, the radial glial marker, brain lipid binding protein (BLBP), and GFAP. Nestin was upregulated by 3 DPI and declined between 7 and 49 DPI in all regions, and GFAP increased and remained above naïve levels at all timepoints. BLBP increased early and remained high along the lesion border and spared white matter, but was expressed transiently by cells lining the central canal and in a unique population of small cells found within the lesion and in gray matter rostral and caudal to the border. The results demonstrate that the astrocyte response to SCI is regionally heterogeneous, and suggests astrocyte populations that could be targeted by interventions.
Collapse
Affiliation(s)
- Robin E White
- Neuroscience Graduate Studies Program, Ohio State University, Columbus, Ohio 43210, USA
| | | | | |
Collapse
|
39
|
Abstract
For many years the mammalian CNS has been seen as an organ that is unable to regenerate. However, it was also long known that lower vertebrate species are capable of impressive regeneration of CNS structures. How did this situation arise through evolution? Increasing cellular and molecular understanding of regeneration in different animal species coupled with studies of adult neurogenesis in mammals is providing a basis for addressing this question. Here we compare CNS regeneration among vertebrates and speculate on how this ability may have emerged or been restricted.
Collapse
|