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Momeni HR, Jarahzadeh M, Farjad E. Glutamate Excitotoxicity; a Possible Mechanism for Apoptosis of Motoneurons in Adult Mouse Spinal Cord Slices. NEUROPHYSIOLOGY+ 2021. [DOI: 10.1007/s11062-021-09898-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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2
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Wood CR, Juárez EH, Ferrini F, Myint P, Innes J, Lossi L, Merighi A, Johnson WEB. Mesenchymal stem cell conditioned medium increases glial reactivity and decreases neuronal survival in spinal cord slice cultures. Biochem Biophys Rep 2021; 26:100976. [PMID: 33718633 PMCID: PMC7933697 DOI: 10.1016/j.bbrep.2021.100976] [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: 12/07/2020] [Revised: 02/22/2021] [Accepted: 02/22/2021] [Indexed: 12/13/2022] Open
Abstract
Ex vivo spinal cord slice cultures (SCSC) allow study of spinal cord circuitry, maintaining stimuli responses comparable to live animals. Previously, we have shown that mesenchymal stem/stromal cell (MSC) transplantation in vivo reduced inflammation and increased nerve regeneration but MSC survival was short-lived, highlighting that beneficial action may derive from the secretome. Previous in vitro studies of MSC conditioned medium (CM) have also shown increased neuronal growth. In this study, murine SCSC were cultured in canine MSC CM (harvested from the adipose tissue of excised inguinal fat) and cell phenotypes analysed via immunohistochemistry and confocal microscopy. SCSC in MSC CM displayed enhanced viability after propidium iodide staining. GFAP immunoreactivity was significantly increased in SCSC in MSC CM compared to controls, but with no change in proteoglycan (NG2) immunoreactivity. In contrast, culture in MSC CM significantly decreased the prevalence of βIII-tubulin immunoreactive neurites, whilst Ca2+ transients per cell were significantly increased. These ex vivo results contradict previous in vitro and in vivo reports of how MSC and their secretome may affect the microenvironment of the spinal cord after injury and highlight the importance of a careful comparison of the different experimental conditions used to assess the potential of cell therapies for the treatment of spinal cord injury. Treatment of spinal slices with conditioned medium caused cell phenotypic changes. Resident astrocytes become hypertrophic, yet neuronal axonal outgrowth reduced. Signalling cells reduced in number but increased their signalling activity. Highlights importance of simulation systems and systemic factors in CNS models.
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Affiliation(s)
- Chelsea R Wood
- Department of Biological Sciences, University of Chester, Parkgate Road, Chester, CH1 4BJ, UK
| | - Esri H Juárez
- Department of Veterinary Sciences, University of Turin, Largo Paolo Braccini 2, I-10095, Grugliasco, TO, Italy
| | - Francesco Ferrini
- Department of Veterinary Sciences, University of Turin, Largo Paolo Braccini 2, I-10095, Grugliasco, TO, Italy.,Université Laval, Department of Psychiatry and Neuroscience, G1K 7P4, Québec, Canada
| | - Peter Myint
- Veterinary Tissue Bank Ltd., No.1 The Long Barn, Brynkinalt Business Centre, Chirk, Wrexham, LL14 5NS, UK
| | - John Innes
- Veterinary Tissue Bank Ltd., No.1 The Long Barn, Brynkinalt Business Centre, Chirk, Wrexham, LL14 5NS, UK
| | - Laura Lossi
- Department of Veterinary Sciences, University of Turin, Largo Paolo Braccini 2, I-10095, Grugliasco, TO, Italy
| | - Adalberto Merighi
- Department of Veterinary Sciences, University of Turin, Largo Paolo Braccini 2, I-10095, Grugliasco, TO, Italy
| | - William E B Johnson
- Department of Biological Sciences, University of Chester, Parkgate Road, Chester, CH1 4BJ, UK
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3
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Santi S, Corridori I, Pugno NM, Motta A, Migliaresi C. Injectable Scaffold-Systems for the Regeneration of Spinal Cord: Advances of the Past Decade. ACS Biomater Sci Eng 2021; 7:983-999. [PMID: 33523634 DOI: 10.1021/acsbiomaterials.0c01779] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Nowadays, whenever is possible and as an alternative to open spine surgery, minimally invasive procedures are preferred to treat spinal cord injuries (SCI), with percutaneous injections or small incisions, that are faster, less traumatic, and require less recovery time. Injectable repair systems are based on materials that can be injected in the lesion site, can eventually be loaded with drugs or even cells, and act as scaffolds for the lesion repair. The review analyzes papers written from 2010 onward on injectable materials/systems used/proposed for the regenerative and combinatorial therapies of SCI and discusses the in vivo models that have been used to validate them.
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Affiliation(s)
- Sofia Santi
- BIOTech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento, Via delle Regole 101, 38123 Trento, Italy.,Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Ilaria Corridori
- Laboratory of Bio-inspired, Bionic, Nano, Meta Materials & Mechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento, Italy
| | - Nicola M Pugno
- Laboratory of Bio-inspired, Bionic, Nano, Meta Materials & Mechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento, Italy.,School of Engineering and Material Science, Queen Mary University of London, Mile End Road, E1 4NS London, United Kingdom
| | - Antonella Motta
- BIOTech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento, Via delle Regole 101, 38123 Trento, Italy.,Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Claudio Migliaresi
- BIOTech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento, Via delle Regole 101, 38123 Trento, Italy.,Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
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Singh NK, Khaliq S, Patel M, Wheeler N, Vedula S, Freeman JW, Firestein BL. Uric acid released from poly(ε-caprolactone) fibers as a treatment platform for spinal cord injury. J Tissue Eng Regen Med 2021; 15:14-23. [PMID: 33175472 PMCID: PMC7864535 DOI: 10.1002/term.3153] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 09/28/2020] [Accepted: 10/12/2020] [Indexed: 01/19/2023]
Abstract
Spinal cord injury (SCI) is characterized by a primary mechanical phase of injury, resulting in physical tissue damage, and a secondary pathological phase, characterized by biochemical processes contributing to inflammation, neuronal death, and axonal demyelination. Glutamate-induced excitotoxicity (GIE), in which excess glutamate is released into synapses and overstimulates glutamate receptors, is a major event in secondary SCI. GIE leads to mitochondrial damage and dysfunction, release of reactive oxygen species (ROS), DNA damage, and cell death. There is no clinical treatment that targets GIE after SCI, and there is a need for therapeutic targets for secondary damage in patients. Uric acid (UA) acts as an antioxidant and scavenges free radicals, upregulates glutamate transporters on astrocytes, and preserves neuronal viability in in vitro and in vivo SCI models, making it a promising therapeutic candidate. However, development of a drug release platform that delivers UA locally to the injured region in a controlled manner is crucial, as high systemic UA concentrations can be detrimental. Here, we used the electrospinning technique to synthesize UA-containing poly(ɛ-caprolactone) fiber mats that are biodegradable, biocompatible, and have a tunable degradation rate. We optimized delivery of UA as a burst within 20 min from uncoated fibers and sustained release over 2 h with poly(ethylene glycol) diacrylate coating. We found that both of these fibers protected neurons and decreased ROS generation from GIE in organotypic spinal cord slice culture. Thus, fiber mats represent a promising therapeutic for UA release to treat patients who have suffered a SCI.
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Affiliation(s)
- Nisha K. Singh
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Molecular Biosciences Graduate Program, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Salman Khaliq
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
- Biomedical Engineering Graduate Program, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Mann Patel
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - N’Dea Wheeler
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Sudeepti Vedula
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Joseph W. Freeman
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Bonnie L. Firestein
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
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Hodges NA, Barr RW, Murfee WL. The maintenance of adult peripheral adult nerve and microvascular networks in the rat mesentery culture model. J Neurosci Methods 2020; 346:108923. [PMID: 32888964 DOI: 10.1016/j.jneumeth.2020.108923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/23/2020] [Accepted: 08/24/2020] [Indexed: 11/18/2022]
Abstract
BACKGROUND Neurovascular patterning is an emerging area of microvascular research. While overlapping molecular signals highlight links between angiogenesis and neurogenesis, advancing our understanding is limited by a lack of in vitro models containing both systems. One potential model is the rat mesentery culture model, which our laboratory has recently introduced as an ex vivo tool to investigate cellular dynamics during angiogenesis in a microvascular network scenario. The objective of this study was to demonstrate the use of the rat mesentery culture model as an ex vivo platform for maintaining the spatiotemporal relationship between blood vessels and peripheral nerves during angiogenesis in adult microvascular networks. METHODS Adult male Wistar rat mesenteric tissue windows were harvested, rinsed in sterile DPBS and medium and then cultured per group: 1) MEM alone and 2) NBM with NGF and 20 % FBS (nerve culture medium). On day 3 post culture tissues were labeled for endothelial (PECAM) and neural (class III β-tubulin, NG2, tyrosine hydroxylase, CGRP) markers. RESULTS In MEM alone tissues nerve segment degeneration was supported by discontinuous nerve or absence of nerve marker labeling. Nerve presence at the arteriole level and capillary level was maintained for the nerve culture medium group compared to day 0, non-cultured control group (unstimulated). COMPARISON WITH EXISTING METHODS AND CONCLUSIONS The results support the use of specific medium types to maintain nerve presence across cultured microvascular networks and implicates the rat mesentery culture model as a novel ex vivo tool for investigating neurovascular patterning in adult tissues.
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Affiliation(s)
- Nicholas A Hodges
- Tulane University, Department of Biomedical Engineering, New Orleans, LA, 70118, United States; University of Florida, Department of Biomedical Engineering, Gainesville, FL, 32611, United States
| | - Ryan W Barr
- Tulane University, Department of Biomedical Engineering, New Orleans, LA, 70118, United States
| | - Walter L Murfee
- Tulane University, Department of Biomedical Engineering, New Orleans, LA, 70118, United States; University of Florida, Department of Biomedical Engineering, Gainesville, FL, 32611, United States.
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Lin C, Calzarossa C, Fernandez-Zafra T, Liu J, Li X, Ekblad-Nordberg Å, Vazquez-Juarez E, Codeluppi S, Holmberg L, Lindskog M, Uhlén P, Åkesson E. Human ex vivo spinal cord slice culture as a useful model of neural development, lesion, and allogeneic neural cell therapy. Stem Cell Res Ther 2020; 11:320. [PMID: 32727554 PMCID: PMC7390865 DOI: 10.1186/s13287-020-01771-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/18/2020] [Accepted: 06/12/2020] [Indexed: 12/14/2022] Open
Abstract
Background There are multiple promising treatment strategies for central nervous system trauma and disease. However, to develop clinically potent and safe treatments, models of human-specific conditions are needed to complement in vitro and in vivo animal model-based studies. Methods We established human brain stem and spinal cord (cross- and longitudinal sections) organotypic cultures (hOCs) from first trimester tissues after informed consent by donor and ethical approval by the Regional Human Ethics Committee, Stockholm (lately referred to as Swedish Ethical Review Authority), and The National Board of Health and Welfare, Sweden. We evaluated the stability of hOCs with a semi-quantitative hOC score, immunohistochemistry, flow cytometry, Ca2+ signaling, and electrophysiological analysis. We also applied experimental allogeneic human neural cell therapy after injury in the ex vivo spinal cord slices. Results The spinal cord hOCs presented relatively stable features during 7–21 days in vitro (DIV) (except a slightly increased cell proliferation and activated glial response). After contusion injury performed at 7 DIV, a significant reduction of the hOC score, increase of the activated caspase-3+ cell population, and activated microglial populations at 14 days postinjury compared to sham controls were observed. Such elevation in the activated caspase-3+ population and activated microglial population was not observed after allogeneic human neural cell therapy. Conclusions We conclude that human spinal cord slice cultures have potential for future structural and functional studies of human spinal cord development, injury, and treatment strategies.
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Affiliation(s)
- Chenhong Lin
- Department of Neurobiology, Care Sciences and Society, Div. of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
| | - Cinzia Calzarossa
- Department of Neurobiology, Care Sciences and Society, Div. of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden.,Department of Neurology and Laboratory of Neuroscience, Università degli Studi diMilan, Milan, Italy
| | - Teresa Fernandez-Zafra
- Division of Molecular Neurobiology, Departmentof Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Jia Liu
- Department of Neurobiology, Care Sciences and Society, Div. of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden.,Department of Neurology, Shengjing Hospital of China Medical University, Shenyang, People's Republic of China
| | - Xiaofei Li
- Department of Neurobiology, Care Sciences and Society, Div. of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
| | - Åsa Ekblad-Nordberg
- Department of Clinical Science, Intervention and Technology, Div. of Obstetrics and Gynecology, Karolinska Institutet, Stockholm, Sweden
| | - Erika Vazquez-Juarez
- Department of Neurobiology, Care Sciences and Society, Div. of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
| | - Simone Codeluppi
- Division of Molecular Neurobiology, Departmentof Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Lena Holmberg
- Department of Neurobiology, Care Sciences and Society, Div. of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
| | - Maria Lindskog
- Department of Neurobiology, Care Sciences and Society, Div. of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
| | - Per Uhlén
- Division of Molecular Neurobiology, Departmentof Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Elisabet Åkesson
- Department of Neurobiology, Care Sciences and Society, Div. of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden. .,The R&D Unit, Stockholms Sjukhem, Stockholm, Sweden.
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7
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Patar A, Dockery P, McMahon S, Howard L. Ex Vivo Rat Transected Spinal Cord Slices as a Model to Assess Lentiviral Vector Delivery of Neurotrophin-3 and Short Hairpin RNA against NG2. BIOLOGY 2020; 9:biology9030054. [PMID: 32183469 PMCID: PMC7150802 DOI: 10.3390/biology9030054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 03/11/2020] [Accepted: 03/13/2020] [Indexed: 01/06/2023]
Abstract
The failure of the spinal cord to regenerate can be attributed both to a lack of trophic support for regenerating axons and to upregulation of inhibitory factors such as chondroitin sulphate proteoglycans including NG2 following injury. Lentiviral vector-mediated gene therapy is a possible strategy for treating spinal cord injury (SCI). This study investigated the effect of lentiviral vectors expressing Neurotrophin-3 (NT-3) and short-hairpin RNA against NG2 (NG2 sh) to enhance neurite outgrowth in in vitro and ex vivo transection injury models. Conditioned medium from cells transduced with NT-3 or shNG2 lentiviruses caused a significant increase in neurite length of primary dorsal root ganglia neurons compared to the control group in vitro. In an ex vivo organotypic slice culture (OSC) transduction with Lenti-NT-3 promoted axonal growth. Transducing OSCs with a combination of Lenti-NT-3/NG2 sh lead to a further increase in axonal growth but only in injured slices and only within the region adjacent to the site of injury. These findings suggest that the combination of lentiviral NT-3 and NG2 sh reduced NG2 levels and provided a more favourable microenvironment for neuronal regeneration after SCI. This study also shows that OSCs may be a useful platform for studying glial scarring and potential SCI treatments.
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Affiliation(s)
- Azim Patar
- Discipline of Anatomy, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, H91 YR71 Galway, Ireland; (A.P.); (P.D.)
- Department of Neuroscience, School of Medical Sciences, Universiti Sains Malaysia, Gelugor 11800, Malaysia
| | - Peter Dockery
- Discipline of Anatomy, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, H91 YR71 Galway, Ireland; (A.P.); (P.D.)
| | - Siobhan McMahon
- Discipline of Anatomy, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, H91 YR71 Galway, Ireland; (A.P.); (P.D.)
- Correspondence: (S.M.); (L.H.); Tel.: +353-91495268 (L.H.)
| | - Linda Howard
- Regenerative Medicine Institute (REMEDI), College of Medicine Nursing and Health Sciences, National University of Ireland Galway, H91 YR71 Galway, Ireland
- Correspondence: (S.M.); (L.H.); Tel.: +353-91495268 (L.H.)
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Mobini S, Song YH, McCrary MW, Schmidt CE. Advances in ex vivo models and lab-on-a-chip devices for neural tissue engineering. Biomaterials 2019; 198:146-166. [PMID: 29880219 PMCID: PMC6957334 DOI: 10.1016/j.biomaterials.2018.05.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 04/25/2018] [Accepted: 05/07/2018] [Indexed: 02/08/2023]
Abstract
The technologies related to ex vivo models and lab-on-a-chip devices for studying the regeneration of brain, spinal cord, and peripheral nerve tissues are essential tools for neural tissue engineering and regenerative medicine research. The need for ex vivo systems, lab-on-a-chip technologies and disease models for neural tissue engineering applications are emerging to overcome the shortages and drawbacks of traditional in vitro systems and animal models. Ex vivo models have evolved from traditional 2D cell culture models to 3D tissue-engineered scaffold systems, bioreactors, and recently organoid test beds. In addition to ex vivo model systems, we discuss lab-on-a-chip devices and technologies specifically for neural tissue engineering applications. Finally, we review current commercial products that mimic diseased and normal neural tissues, and discuss the future directions in this field.
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Affiliation(s)
- Sahba Mobini
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Young Hye Song
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Michaela W McCrary
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Christine E Schmidt
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA.
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Pandamooz S, Salehi MS, Zibaii MI, Safari A, Nabiuni M, Ahmadiani A, Dargahi L. Modeling traumatic injury in organotypic spinal cord slice culture obtained from adult rat. Tissue Cell 2019; 56:90-97. [DOI: 10.1016/j.tice.2019.01.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/04/2018] [Accepted: 01/08/2019] [Indexed: 12/16/2022]
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Llufriu-Dabén G, Meffre D, Massaad C, Jafarian-Tehrani M. A novel model of trauma-induced cerebellar injury and myelin loss in mouse organotypic cerebellar slice cultures using live imaging. J Neurosci Methods 2019; 311:385-393. [DOI: 10.1016/j.jneumeth.2018.09.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 09/13/2018] [Accepted: 09/18/2018] [Indexed: 12/16/2022]
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Patar A, Dockery P, Howard L, McMahon SS. Cell viability in three ex vivo rat models of spinal cord injury. J Anat 2018; 234:244-251. [PMID: 30417349 DOI: 10.1111/joa.12909] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/2018] [Indexed: 12/18/2022] Open
Abstract
Spinal cord injury (SCI) is a devastating disorder that has a poor prognosis of recovery. Animal models of SCI are useful to understand the pathophysiology of SCI and the potential use of therapeutic strategies for human SCI. Ex vivo models of central nervous system (CNS) trauma, particularly mechanical trauma, have become important tools to complement in vivo models of injury in order to reproduce the sequelae of human CNS injury. Ex vivo organotypic slice cultures (OSCs) provide a reliable model platform for the study of cell dynamics and therapeutic intervention following SCI. In addition, these ex vivo models support the 3R concept of animal use in SCI research - replacement, reduction and refinement. Ex vivo models cannot be used to monitor functional recovery, nor do they have the intact blood supply of the in vivo model systems. However, the ex vivo models appear to reproduce many of the post traumatic events including acute and secondary injury mechanisms. Several well-established OSC models have been developed over the past few years for experimental spinal injuries ex vivo in order to understand the biological response to injury. In this study, we investigated cell viability in three ex vivo OSC models of SCI: stab injury, transection injury and contusion injury. Injury was inflicted in postnatal day 4 rat spinal cord slices. Stab injury was performed using a needle on transverse slices of spinal cord. Transection injury was performed on longitudinal slices of spinal cord using a double blade technique. Contusion injury was performed on longitudinal slices of spinal cord using an Infinite Horizon impactor device. At days 3 and 10 post-injury, viability was measured using dual staining for propidium iodide and fluorescein diacetate. In all ex vivo SCI models, the slices showed more live cells than dead cells over 10 days in culture, with higher cell viability in control slices compared with injured slices. Although no change in cell viability was observed between time-points in stab- and contusion-injured OSCs, a reduction in cell viability was observed over time in transection-injured OSCs. Taken together, ex vivo SCI models are a useful and reliable research tool that reduces the cost and time involved in carrying out animal studies. The use of OSC models provides a simple way to study the cellular consequences following SCI, and they can also be used to investigate potential therapeutics regimes for the treatment of SCI.
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Affiliation(s)
- Azim Patar
- Discipline of Anatomy and NCBES Galway Neuroscience Centre, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Galway, Ireland.,Department of Neuroscience, School of Medical Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Peter Dockery
- Discipline of Anatomy, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Galway, Ireland
| | - Linda Howard
- Regenerative Medicine Institute (REMEDI), College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Galway, Ireland
| | - Siobhan S McMahon
- Discipline of Anatomy and NCBES Galway Neuroscience Centre, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Galway, Ireland
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12
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Patar A, Dockery P, Howard L, McMahon S. Analysis of reactive astrocytes and NG2 proteoglycan in ex vivo rat models of spinal cord injury. J Neurosci Methods 2018; 311:418-425. [PMID: 30267723 DOI: 10.1016/j.jneumeth.2018.09.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 09/25/2018] [Accepted: 09/25/2018] [Indexed: 12/22/2022]
Abstract
BACKGROUND The use of animals to model spinal cord injury (SCI) requires extensive post-operative care and can be expensive, which makes an alternative model extremely attractive. The use ofex vivo slice cultures is an alternative way to study the pathophysiological changes that can mimic in vivo conditions and support the 3Rs (replacement, reduction and refinement) of animal use in SCI research models. NEW METHOD In this study the presence of reactive astrocytes and NG2 proteoglycans was investigated in two ex vivo models of SCI; stab injury and transection injury. Stereological analysis to measure immunohistochemical staining was performed on the scar and injury zones to detect astrocytes and the chondroitin sulphate proteoglycan NG2. RESULTS The volume fraction (Vv) of reactive astrocytes and NG2 proteoglycans increased significantly between day 3 and day 10 post injury in both ex vivo models. This data shows how ex vivo SCI models are a useful research tool allowing reduction of research cost and time involved in carrying out animal studies, as well as reducing the numbers of animals used. COMPARISON WITH EXISTING METHOD This is the first evidence of an ex vivo stab injury model of SCI and also the first comparison of immunohistochemical staining for injury markers within stab injured and transection injured ex vivo slice cultures. CONCLUSIONS The use of organotypic slice culture models provide a simple way to study the cellular consequences following SCI and they can also be used as a platform for potential therapeutics regimes for the treatment of SCI.
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Affiliation(s)
- Azim Patar
- Discipline of Anatomy and NCBES Galway Neuroscience Centre, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Ireland; Department of Neuroscience, School of Medical Sciences, Universiti Sains Malaysia, Malaysia
| | - Peter Dockery
- Discipline of Anatomy, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Ireland
| | - Linda Howard
- Regenerative Medicine Institute (REMEDI), College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Ireland
| | - Siobhan McMahon
- Discipline of Anatomy and NCBES Galway Neuroscience Centre, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Ireland.
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13
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Pandamooz S, Salehi MS, Zibaii MI, Ahmadiani A, Nabiuni M, Dargahi L. Epidermal neural crest stem cell-derived glia enhance neurotrophic elements in an ex vivo model of spinal cord injury. J Cell Biochem 2018; 119:3486-3496. [PMID: 29143997 DOI: 10.1002/jcb.26520] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 11/13/2017] [Indexed: 01/09/2023]
Abstract
Growing evidence that cell-based therapies can improve recovery outcome in spinal cord injury (SCI) models substantiates their application for treatment of human with SCI. To address the effectiveness of these stem cells, potential candidates should be evaluated in proper SCI platform that allows direct real-time monitoring. In this study, the role of epidermal neural crest stem cells (EPI-NCSCs) was elucidated in an ex vivo model of SCI, and valproic acid (VPA) was administered to ameliorate the inhospitable context of injury for grafted EPI-NCSCs. Here the contusion was induced in organotypic spinal cord slice culture at day seven in vitro using a weight drop device and one hour post injury the GFP- expressing EPI-NCSCs were grafted followed by VPA administration. The evaluation of treated slices seven days after injury revealed that grafted stem cells survived on the injured slices and expressed GFAP, whereas they did not express any detectable levels of the neural progenitor marker doublecortin (DCX), which was expressed prior to transplantation. Immunoblotting data demonstrated that the expression of GFAP, BDNF, neurotrophin-3 (NT3), and Bcl2 increased significantly in stem cell treated slices. This study illustrated that the fate of transplanted stem cells has been directed to the glial lineage in the ex vivo context of injury and EPI-NCSCs may ameliorate the SCI condition through releasing neurotrophic factors directly and/or via inducing resident spinal cord cells.
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Affiliation(s)
- Sareh Pandamooz
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Mohammad S Salehi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad I Zibaii
- Laser and Plasma Research institute, Shahid Beheshti University, Tehran, Iran
| | - Abolhassan Ahmadiani
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Nabiuni
- Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Leila Dargahi
- NeuroBiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Liu JJ, Ding XY, Xiang L, Zhao F, Huang SL. A novel method for oxygen glucose deprivation model in organotypic spinal cord slices. Brain Res Bull 2017; 135:163-169. [DOI: 10.1016/j.brainresbull.2017.10.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 10/10/2017] [Accepted: 10/12/2017] [Indexed: 12/20/2022]
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15
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Tan GA, Furber KL, Thangaraj MP, Sobchishin L, Doucette JR, Nazarali AJ. Organotypic Cultures from the Adult CNS: A Novel Model to Study Demyelination and Remyelination Ex Vivo. Cell Mol Neurobiol 2017; 38:317-328. [DOI: 10.1007/s10571-017-0529-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 07/31/2017] [Indexed: 12/11/2022]
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16
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Fernandez-Zafra T, Codeluppi S, Uhlén P. An ex vivo spinal cord injury model to study ependymal cells in adult mouse tissue. Exp Cell Res 2017; 357:236-242. [DOI: 10.1016/j.yexcr.2017.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 05/31/2017] [Accepted: 06/01/2017] [Indexed: 12/24/2022]
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17
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Pandamooz S, Salehi MS, Nabiuni M, Dargahi L. Valproic acid preserves motoneurons following contusion in organotypic spinal cord slice culture. J Spinal Cord Med 2017; 40:100-106. [PMID: 27576744 PMCID: PMC5376140 DOI: 10.1080/10790268.2016.1213518] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
OBJECTIVE Spinal cord injury (SCI) is a devastating condition causing neuronal loss. A key challenge in treatment of SCI is how to retain neurons after injury. Valproic acid (VPA) is a drug recently has been appreciated for its neuroprotective and neurotrophic properties in various SCI models. In this study the role of VPA was assessed in organotypic spinal cord slice culture following the contusion. DESIGN The lumbar enlargement of adult rat was cut transversely and slices were cultured. Seven days after culturing, injury was induced by dropping a 0.5 gram weight from 3 cm height on the slice surface. One hour after injury, the VPA was administered at 1, 5 and 10 µM concentrations. Afterward, at day 1 and 3 post injury (DPI: 1 and 3) propidium iodide (PI) and immunohistochemistry staining were performed to evaluate the cell death, NeuN and β-Tubulin expression, respectively. RESULTS The PI staining of slices at DPI: 1 and 3 following treatment with VPA revealed significant decreases in the cell death in all three concentrations comparing to the non-treated group. Also immunostaining showed VPA only at 5 µM concentration considerably rescued ventral horn' MNs from death and protected the neuronal integrity. CONCLUSION The results of this study indicate applying VPA one hour after injury can prevent the death of a majority of cells, importantly MNs and preserve the neuronal integrity. Since the first 24 hours after SCI is a critical period for employing any treatment, VPA can be considered as an option for further evaluation.
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Affiliation(s)
- Sareh Pandamooz
- Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran,Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran,Correspondence to: Sareh Pandamooz Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran.
| | - Mohammad Saied Salehi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Nabiuni
- Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Leila Dargahi
- NeuroBiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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18
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Obien MEJ, Gong W, Frey U, Bakkum DJ. CMOS-Based High-Density Microelectrode Arrays: Technology and Applications. SERIES IN BIOENGINEERING 2017. [DOI: 10.1007/978-981-10-3957-7_1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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19
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Al-Ali H, Beckerman SR, Bixby JL, Lemmon VP. In vitro models of axon regeneration. Exp Neurol 2016; 287:423-434. [PMID: 26826447 DOI: 10.1016/j.expneurol.2016.01.020] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 01/20/2016] [Accepted: 01/25/2016] [Indexed: 12/31/2022]
Abstract
A variety of in vitro models have been developed to understand the mechanisms underlying the regenerative failure of central nervous system (CNS) axons, and to guide pre-clinical development of regeneration-promoting therapeutics. These range from single-cell based assays that typically focus on molecular mechanisms to organotypic assays that aim to recapitulate in vivo behavior. By utilizing a combination of models, researchers can balance the speed, convenience, and mechanistic resolution of simpler models with the biological relevance of more complex models. This review will discuss a number of models that have been used to build our understanding of the molecular mechanisms of CNS axon regeneration.
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Affiliation(s)
- Hassan Al-Ali
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Samuel R Beckerman
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - John L Bixby
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Center for Computational Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Molecular & Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| | - Vance P Lemmon
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Center for Computational Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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20
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Pandamooz S, Nabiuni M, Miyan J, Ahmadiani A, Dargahi L. Organotypic Spinal Cord Culture: a Proper Platform for the Functional Screening. Mol Neurobiol 2015; 53:4659-74. [PMID: 26310972 DOI: 10.1007/s12035-015-9403-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 08/17/2015] [Indexed: 12/11/2022]
Abstract
Recent improvements in organotypic slice culturing and its accompanying technological innovations have made this biological preparation increasingly useful ex vivo experimental model. Among organotypic slice cultures obtained from various central nervous regions, spinal cord slice culture is an absorbing model that represents several unique advantages over other current in vitro and in vivo models. The culture of developing spinal cord slices, as allows real-time observation of embryonic cells behaviors, is an instrumental platform for developmental investigation. Importantly, due to the ability of ex vivo models to recapitulate different aspects of corresponding in vivo conditions, these models have been subject of various manipulations to derive disease-relevant slice models. Moreover spinal cord slice cultures represent a potential platform for screening of different pharmacological agents and evaluation of cell transplantation and neuroregenerative materials. In this review, we will focus on studies carried out using the ex vivo model of spinal cord slice cultures and main advantages linked to practicality of these slices in both normal and neuropathological diseases and summarize them in different categories based on application.
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Affiliation(s)
- Sareh Pandamooz
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Mohammad Nabiuni
- Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Jaleel Miyan
- Neurobiology Research Group, Faculty of Life Sciences, The University of Manchester, Manchester, UK
| | - Abolhassan Ahmadiani
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Leila Dargahi
- NeuroBiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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21
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Abstract
Organotypic hippocampal slice cultures (OHSCs) have been used as a powerful ex vivo model for decades. They have been used successfully in studies of neuronal death, microglial activation, mossy fiber regeneration, neurogenesis, and drug screening. As a pre-animal experimental phase for physiologic and pathologic brain research, OHSCs offer outcomes that are relatively closer to those of whole-animal studies than outcomes obtained from cell culture in vitro. At the same time, mechanisms can be studied more precisely in OHSCs than they can be in vivo. Here, we summarize stroke and traumatic brain injury research that has been carried out in OHSCs and review classic experimental applications of OHSCs and its limitations.
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22
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Glazova MV, Pak ES, Murashov AK. Neurogenic potential of spinal cord organotypic culture. Neurosci Lett 2015; 594:60-5. [PMID: 25805458 DOI: 10.1016/j.neulet.2015.03.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 03/19/2015] [Accepted: 03/20/2015] [Indexed: 11/25/2022]
Abstract
There are several neurogenic niches in the adult mammalian central nervous system. In the central nervous system, neural stem cells (NSC) localize not only to the periventricular area, but are also diffusely distributed in the parenchyma. Here, we assessed neurogenic potential of organotypic cultures prepared from adult mouse spinal cord. Slices were placed on Millipore inserts for organotypic culture and incubated in neurobasal media supplemented with B27 and N2 for up to 9 weeks. After 3-4 weeks, the cell's aggregates formed in the slices. The aggregate's cells were BrdU-uptake, nestin and alkaline phosphatase positive. At the later stage of incubation, we observed Oct3/4 in the inner mass of the neurospheres as well as expression of Dppa1, which is an Oct-4 downstream target gene and a marker for pluripotency. To check differentiation, the formed neurospheres were isolated and cultured for several days in differentiation media. The obtained data demonstrated the cells from isolated neurospheres differentiate into astrocytes and MAP2-positive neurons. Immunostaining for HB9 and Lim2 revealed subsequent differentiation of MAP2-positive cells into motor neurons and interneurons, respectively. We hypothesized neuronal loss and/or long-term culturing of spinal cord slices may trigger a reset of the internal cell program and promote proliferation and further differentiation of NSC.
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Affiliation(s)
- Margarita V Glazova
- Departments of Physiology, The Brody School of Medicine, East Carolina University School of Medicine, Brody Building, 600 Moye Boulevard, Greenville, NC 27834, USA.
| | - Elena S Pak
- Departments of Physiology, The Brody School of Medicine, East Carolina University School of Medicine, Brody Building, 600 Moye Boulevard, Greenville, NC 27834, USA
| | - Alexander K Murashov
- Departments of Physiology, The Brody School of Medicine, East Carolina University School of Medicine, Brody Building, 600 Moye Boulevard, Greenville, NC 27834, USA
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23
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Hopkins AM, DeSimone E, Chwalek K, Kaplan DL. 3D in vitro modeling of the central nervous system. Prog Neurobiol 2015; 125:1-25. [PMID: 25461688 PMCID: PMC4324093 DOI: 10.1016/j.pneurobio.2014.11.003] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2014] [Revised: 10/12/2014] [Accepted: 11/15/2014] [Indexed: 12/15/2022]
Abstract
There are currently more than 600 diseases characterized as affecting the central nervous system (CNS) which inflict neural damage. Unfortunately, few of these conditions have effective treatments available. Although significant efforts have been put into developing new therapeutics, drugs which were promising in the developmental phase have high attrition rates in late stage clinical trials. These failures could be circumvented if current 2D in vitro and in vivo models were improved. 3D, tissue-engineered in vitro systems can address this need and enhance clinical translation through two approaches: (1) bottom-up, and (2) top-down (developmental/regenerative) strategies to reproduce the structure and function of human tissues. Critical challenges remain including biomaterials capable of matching the mechanical properties and extracellular matrix (ECM) composition of neural tissues, compartmentalized scaffolds that support heterogeneous tissue architectures reflective of brain organization and structure, and robust functional assays for in vitro tissue validation. The unique design parameters defined by the complex physiology of the CNS for construction and validation of 3D in vitro neural systems are reviewed here.
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Affiliation(s)
- Amy M Hopkins
- Department of Biomedical Engineering, Tufts University, Science & Technology Center, 4 Colby Street, Medford, MA 02155, USA
| | - Elise DeSimone
- Department of Biomedical Engineering, Tufts University, Science & Technology Center, 4 Colby Street, Medford, MA 02155, USA
| | - Karolina Chwalek
- Department of Biomedical Engineering, Tufts University, Science & Technology Center, 4 Colby Street, Medford, MA 02155, USA
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Science & Technology Center, 4 Colby Street, Medford, MA 02155, USA.
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24
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Spitzbarth I, Cana A, Hahn K, Hansmann F, Baumgärtner W. Associated occurrence of p75 neurotrophin receptor expressing aldynoglia and microglia/macrophages in long term organotypic murine brain slice cultures. Brain Res 2014; 1595:29-42. [PMID: 25446435 DOI: 10.1016/j.brainres.2014.11.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 11/03/2014] [Accepted: 11/07/2014] [Indexed: 11/17/2022]
Abstract
Growth-promoting aldynoglia, characterized by the expression of the prototype immature Schwann cell marker p75 neurotrophin receptor (NTR) have been shown to occur in some demyelinating diseases. However, the mechanisms determining the emergence and fate of such cells are largely unknown. This study aimed at the identification of such cells and potential triggering factors using an in vitro slice culture approach. Organotypic cerebrum and brain stem slices of adult mice were cultivated for up to 18 days in vitro. Immunohistochemistry for the detection of p75(NTR), CD107b, periaxin, growth associated protein (GAP)-43, and glial fibrillary acidic protein (GFAP) was performed. The results for p75(NTR) were substantiated by the use of in situ hybridization. Cultivation was associated with a progressively increasing spontaneous occurrence of bi- to multipolar p75(NTR)-positive, but periaxin-negative glia, indicative of aldynoglial Schwann cell like cells. Similar cells stained intensely positive for GAP-43, a marker for non-myelinating Schwann cells. The number of p75(NTR) positive glia did not correlate with GFAP expression, but showed a strong correlation with a remarkable spontaneous response of CD107b positive phagocytic microglia/macrophages. Moreover, aldynoglial p75(NTR) immunoreactivity negatively correlated to neuronal p75(NTR) expression, which was lost during culturing. The present results demonstrate that the cultivation of organotypic murine brain slices is accompanied by a spontaneous response of both microglia/macrophages and p75(NTR) positive cells, suggestive of Schwann cell like aldynoglia. The findings highlights the role of microglia/macrophages, which seem to be an important triggering factor, facilitating the occurrence of this unique type of macroglia.
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Affiliation(s)
- I Spitzbarth
- Department of Pathology, University of Veterinary Medicine, Buenteweg 17, D-30559 Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| | - A Cana
- Department of Pathology, University of Veterinary Medicine, Buenteweg 17, D-30559 Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - K Hahn
- Department of Pathology, University of Veterinary Medicine, Buenteweg 17, D-30559 Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - F Hansmann
- Department of Pathology, University of Veterinary Medicine, Buenteweg 17, D-30559 Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - W Baumgärtner
- Department of Pathology, University of Veterinary Medicine, Buenteweg 17, D-30559 Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
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25
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Neurite-J: An Image-J plug-in for axonal growth analysis in organotypic cultures. J Neurosci Methods 2014; 236:26-39. [DOI: 10.1016/j.jneumeth.2014.08.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 07/29/2014] [Accepted: 08/05/2014] [Indexed: 11/23/2022]
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26
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O'Carroll SJ, Becker DL, Davidson JO, Gunn AJ, Nicholson LFB, Green CR. The use of connexin-based therapeutic approaches to target inflammatory diseases. Methods Mol Biol 2014; 1037:519-46. [PMID: 24029957 DOI: 10.1007/978-1-62703-505-7_31] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Alterations in Connexin43 (Cx43) expression levels have been shown to play a role in inflammatory processes including skin wounding and neuroinflammation. Cx43 protein levels increase following a skin wound and can inhibit wound healing. Increased Cx43 has been observed following stroke, epilepsy, ischemia, optic nerve damage, and spinal cord injury with gap junctional communication and hemichannel opening leading to increased secondary damage via the inflammatory response. Connexin43 modulation has been identified as a potential target for protection and repair in neuroinflammation and skin wound repair. This review describes the use of a Cx43 specific antisense oligonucleotide (Cx43 AsODN) and peptide mimetics of the connexin extracellular loop domain to modulate Cx43 expression and/or function in inflammatory disorders of the skin and central nervous system. An overview of the role of connexin43 in inflammatory conditions, how antisense and peptide have allowed us to elucidate the role of Cx43 in these diseases, create models of diseases to test interventions and their potential for use clinically or in current clinical trials is presented. Antisense oligonucleotides are applied topically and have been used to improve wound healing following skin injury. They have also been used to develop ex vivo models of neuroinflammatory diseases that will allow testing of intervention strategies. The connexin mimetic peptides have shown potential in a number of neuroinflammatory disorders in ex vivo models as well as in vivo when delivered directly to the injury site or when delivered systemically.
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Affiliation(s)
- Simon J O'Carroll
- Department of Anatomy with Radiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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New aspects of the pathogenesis of canine distemper leukoencephalitis. Viruses 2014; 6:2571-601. [PMID: 24992230 PMCID: PMC4113784 DOI: 10.3390/v6072571] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 06/11/2014] [Accepted: 06/17/2014] [Indexed: 12/13/2022] Open
Abstract
Canine distemper virus (CDV) is a member of the genus morbillivirus, which is known to cause a variety of disorders in dogs including demyelinating leukoencephalitis (CDV-DL). In recent years, substantial progress in understanding the pathogenetic mechanisms of CDV-DL has been made. In vivo and in vitro investigations provided new insights into its pathogenesis with special emphasis on axon-myelin-glia interaction, potential endogenous mechanisms of regeneration, and astroglial plasticity. CDV-DL is characterized by lesions with a variable degree of demyelination and mononuclear inflammation accompanied by a dysregulated orchestration of cytokines as well as matrix metalloproteinases and their inhibitors. Despite decades of research, several new aspects of the neuropathogenesis of CDV-DL have been described only recently. Early axonal damage seems to represent an initial and progressive lesion in CDV-DL, which interestingly precedes demyelination. Axonopathy may, thus, function as a potential trigger for subsequent disturbed axon-myelin-glia interactions. In particular, the detection of early axonal damage suggests that demyelination is at least in part a secondary event in CDV-DL, thus challenging the dogma of CDV as a purely primary demyelinating disease. Another unexpected finding refers to the appearance of p75 neurotrophin (NTR)-positive bipolar cells during CDV-DL. As p75NTR is a prototype marker for immature Schwann cells, this finding suggests that Schwann cell remyelination might represent a so far underestimated endogenous mechanism of regeneration, though this hypothesis still remains to be proven. Although it is well known that astrocytes represent the major target of CDV infection in CDV-DL, the detection of infected vimentin-positive astrocytes in chronic lesions indicates a crucial role of this cell population in nervous distemper. While glial fibrillary acidic protein represents the characteristic intermediate filament of mature astrocytes, expression of vimentin is generally restricted to immature or reactive astrocytes. Thus, vimentin-positive astrocytes might constitute an important cell population for CDV persistence and spread, as well as lesion progression. In vitro models, such as dissociated glial cell cultures, as well as organotypic brain slice cultures have contributed to a better insight into mechanisms of infection and certain morphological and molecular aspects of CDV-DL. Summarized, recent in vivo and in vitro studies revealed remarkable new aspects of nervous distemper. These new perceptions substantially improved our understanding of the pathogenesis of CDV-DL and might represent new starting points to develop novel treatment strategies.
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28
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An in vitro spinal cord injury model to screen neuroregenerative materials. Biomaterials 2014; 35:3756-65. [DOI: 10.1016/j.biomaterials.2014.01.022] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 01/08/2014] [Indexed: 02/06/2023]
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29
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Stirling DP, Cummins K, Wayne Chen SR, Stys P. Axoplasmic reticulum Ca(2+) release causes secondary degeneration of spinal axons. Ann Neurol 2014; 75:220-9. [PMID: 24395428 DOI: 10.1002/ana.24099] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 11/29/2013] [Accepted: 12/26/2013] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Transected axons of the central nervous system fail to regenerate and instead die back away from the lesion site, resulting in permanent disability. Although both intrinsic (eg, microtubule instability, calpain activation) and extrinsic (ie, macrophages) processes are implicated in axonal dieback, the underlying mechanisms remain uncertain. Furthermore, the precise mechanisms that cause delayed "bystander" loss of spinal axons, that is, ones that were not directly damaged by the initial insult, but succumbed to secondary degeneration, remain unclear. Our goal was to evaluate the role of intra-axonal Ca(2+) stores in secondary axonal degeneration following spinal cord injury. METHODS We developed a 2-photon laser-induced spinal cord injury model to follow morphological and Ca(2+) changes in live myelinated spinal axons acutely following injury. RESULTS Transected axons "died back" within swollen myelin or underwent synchronous pan-fragmentation associated with robust Ca(2+) increases. Spared fibers underwent delayed secondary bystander degeneration. Reducing Ca(2+) release from axonal stores mediated by ryanodine and inositol triphosphate receptors significantly decreased axonal dieback and bystander injury. Conversely, a gain-of-function ryanodine receptor 2 mutant or pharmacological treatments that promote axonal store Ca(2+) release worsened these events. INTERPRETATION Ca(2+) release from intra-axonal Ca(2+) stores, distributed along the length of the axon, contributes significantly to secondary degeneration of axons. This refocuses our approach to protecting spinal white matter tracts, where emphasis has been placed on limiting Ca(2+) entry from the extracellular space across cell membranes, and emphasizes that modulation of axonal Ca(2+) stores may be a key pharmacotherapeutic goal in spinal cord injury.
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Affiliation(s)
- David P Stirling
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Kentucky Spinal Cord Injury Research Center and Departments of Neurological Surgery, Microbiology and Immunology, University of Louisville, Louisville, KY
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Optimized heterologous transfection of viable adult organotypic brain slices using an enhanced gene gun. BMC Res Notes 2013; 6:544. [PMID: 24354851 PMCID: PMC3878247 DOI: 10.1186/1756-0500-6-544] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 12/16/2013] [Indexed: 12/24/2022] Open
Abstract
Background Organotypic brain slices (OTBS) are an excellent experimental compromise between the facility of working with cell cultures and the biological relevance of using animal models where anatomical, morphological, and cellular function of specific brain regions can be maintained. The biological characteristics of OTBS can subsequently be examined under well-defined conditions. They do, however, have a number of limitations; most brain slices are derived from neonatal animals, as it is difficult to properly prepare and maintain adult OTBS. There are ample problems with tissue integrity as OTBS are delicate and frequently become damaged during the preparative stages. Notwithstanding these obstacles, the introduced exogenous proteins into both neuronal cells, and cells imbedded within tissues, have been consistently difficult to achieve. Results Following the ex vivo extraction of adult mouse brains, mounted inside a medium-agarose matrix, we have exploited a precise slicing procedure using a custom built vibroslicer. To transfect these slices we used an improved biolistic transfection method using a custom made low-pressure barrel and novel DNA-coated nanoparticles (40 nm), which are drastically smaller than traditional microparticles. These nanoparticles also minimize tissue damage as seen by a significant reduction in lactate dehydrogenase activity as well as propidium iodide (PI) and dUTP labelling compared to larger traditional gold particles used on these OTBS. Furthermore, following EYFP exogene delivery by gene gun, the 40 nm treated OTBS displayed a significantly larger number of viable NeuN and EYFP positive cells. These OTBS expressed the exogenous proteins for many weeks. Conclusions Our described methodology of producing OTBS, which results in better reproducibility with less tissue damage, permits the exploitation of mature fully formed adult brains for advanced neurobiological studies. The novel 40 nm particles are ideal for the viable biolistic transfection of OTBS by reducing tissue stress while maintaining long term exogene expression.
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Neuroprotection by steroids after neurotrauma in organotypic spinal cord cultures: A key role for progesterone receptors and steroidal modulators of GABAA receptors. Neuropharmacology 2013; 71:46-55. [DOI: 10.1016/j.neuropharm.2013.03.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 02/21/2013] [Accepted: 03/03/2013] [Indexed: 11/23/2022]
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32
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Liu Y, Wang L, Long ZY, Wu YM, Wan Q, Jiang JX, Wang ZG. Inhibiting PTEN protects hippocampal neurons against stretch injury by decreasing membrane translocation of AMPA receptor GluR2 subunit. PLoS One 2013; 8:e65431. [PMID: 23799014 PMCID: PMC3684616 DOI: 10.1371/journal.pone.0065431] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 04/29/2013] [Indexed: 11/18/2022] Open
Abstract
The AMPA type of glutamate receptors (AMPARs)-mediated excitotoxicity is involved in the secondary neuronal death following traumatic brain injury (TBI). But the underlying cellular and molecular mechanisms remain unclear. In this study, the role of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in GluR2-lacking AMPARs mediated neuronal death was investigated through an in vitro stretch injury model of neurons. It was indicated that both the mRNA and protein levels of PTEN were increased in cultured hippocampal neurons after stretch injury, which was associated with the decreasing expression of GluR2 subunits on the surface of neuronal membrane. Inhibition of PTEN activity by its inhibitor can promote the survival of neurons through preventing reduction of GluR2 on membrane. Moreover, the effect of inhibiting GluR2-lacking AMPARs was similar to PTEN suppression-mediated neuroprotective effect in stretch injury-induced neuronal death. Further evidence identified that the total GluR2 protein of neurons was not changed in all groups. So inhibition of PTEN or blockage of GluR2-lacking AMPARs may attenuate the death of hippocampal neurons post injury through decreasing the translocation of GluR2 subunit on the membrane effectively.
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Affiliation(s)
- Yuan Liu
- Department of Research Institute of Surgery, Daping Hospital, the Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing, China
| | - Li Wang
- Department of Research Institute of Surgery, Daping Hospital, the Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing, China
| | - Zai-yun Long
- Department of Research Institute of Surgery, Daping Hospital, the Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing, China
| | - Ya-min Wu
- Department of Research Institute of Surgery, Daping Hospital, the Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing, China
| | - Qi Wan
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Jian-xin Jiang
- Department of Research Institute of Surgery, Daping Hospital, the Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing, China
| | - Zheng-guo Wang
- Department of Research Institute of Surgery, Daping Hospital, the Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing, China
- * E-mail:
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Schizas N, Rojas R, Kootala S, Andersson B, Pettersson J, Hilborn J, Hailer NP. Hyaluronic acid-based hydrogel enhances neuronal survival in spinal cord slice cultures from postnatal mice. J Biomater Appl 2013; 28:825-36. [DOI: 10.1177/0885328213483636] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Numerous biomaterials based on extracellular matrix-components have been developed. It was our aim to investigate whether a hyaluronic acid–based hydrogel improves neuronal survival and tissue preservation in organotypic spinal cord slice cultures. Organotypic spinal cord slice cultures were cultured for 4 days in vitro (div), either on hyaluronic acid–based hydrogel (hyaluronic acid–gel group), collagen gel (collagen group), directly on polyethylene terephthalate membrane inserts (control group), or in the presence of soluble hyaluronic acid (soluble hyaluronic acid group). Cultures were immunohistochemically stained against neuronal antigen NeuN and analyzed by confocal laser scanning microscopy. Histochemistry for choline acetyltransferance, glial fibrillary acidic protein, and Griffonia simplicifolia isolectin B4 followed by quantitative analysis was performed to assess motorneurons and different glial populations. Confocal microscopic analysis showed a 4-fold increase in the number of NeuN-positive neurons in the hyaluronic acid–gel group compared to both collagen ( p < 0.001) and control groups ( p < 0.001). Compared to controls, organotypic spinal cord slice cultures maintained on hyaluronic acid–based hydrogel showed 5.9-fold increased survival of choline acetyltransferance-positive motorneurons ( p = 0.008), 2-fold more numerous resting microglial cells in the white matter ( p = 0.031), and a 61.4% reduction in the number of activated microglial cells within the grey matter ( p = 0.05). Hyaluronic acid–based hydrogel had a shear modulus (G′) of ≈1200 Pascals (Pa), which was considerably higher than the ≈25 Pa measured for collagen gel. Soluble hyaluronic acid failed to improve tissue preservation. In conclusion, hyaluronic acid–based hydrogel improves neuronal and – most notably – motorneuron survival in organotypic spinal cord slice cultures and microglial activation is limited. The positive effects of hyaluronic acid–based hydrogel may at least in part be due to its mechanical properties.
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Affiliation(s)
- Nikos Schizas
- The SpineLab, Institute of Surgical Sciences, Department of Orthopaedics, Uppsala University, Uppsala, Sweden
| | - Ramiro Rojas
- Division of Polymer Chemistry, Department of Materials Chemistry, The Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Sujit Kootala
- Division of Polymer Chemistry, Department of Materials Chemistry, The Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Brittmarie Andersson
- The SpineLab, Institute of Surgical Sciences, Department of Orthopaedics, Uppsala University, Uppsala, Sweden
| | - Jennie Pettersson
- The SpineLab, Institute of Surgical Sciences, Department of Orthopaedics, Uppsala University, Uppsala, Sweden
| | - Jons Hilborn
- Division of Polymer Chemistry, Department of Materials Chemistry, The Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Nils P Hailer
- The SpineLab, Institute of Surgical Sciences, Department of Orthopaedics, Uppsala University, Uppsala, Sweden
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Bock P, Spitzbarth I, Haist V, Stein VM, Tipold A, Puff C, Beineke A, Baumgärtner W. Spatio-temporal development of axonopathy in canine intervertebral disc disease as a translational large animal model for nonexperimental spinal cord injury. Brain Pathol 2012; 23:82-99. [PMID: 22805224 DOI: 10.1111/j.1750-3639.2012.00617.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 07/08/2012] [Indexed: 12/15/2022] Open
Abstract
Spinal cord injury (SCI) represents a devastating central nervous system disease that still lacks sufficient therapies. Here, dogs are increasingly recognized as a preclinical animal model for the development of future therapies. The aim of this study was a detailed characterization of axonopathy in canine intervertebral disc disease, which produces a mixed contusive and compressive injury and functions as a spontaneous translational animal model for human SCI. The results revealed an early occurrence of ultrastructurally distinct axonal swelling. Immunohistochemically, enhanced axonal expression of β-amyloid precursor protein, non-phosphorylated neurofilament (n-NF) and growth-associated protein-43 was detected in the epicenter during acute canine SCI. Indicative of a progressive axonopathy, these changes showed a cranial and caudally accentuated spatial progression in the subacute disease phase. In canine spinal cord slice cultures, immunoreactivity of axons was confined to n-NF. Real-time quantitative polymerase chain reaction of naturally traumatized tissue and slice cultures revealed a temporally distinct dysregulation of the matrix metalloproteinases (MMP)-2 and MMP-9 with a dominating expression of the latter. Contrasting to early axonopathy, diminished myelin basic protein immunoreactivity and phagocytosis were delayed. The results present a basis for assessing new therapies in the canine animal model for translational research that might allow partial extrapolation to human SCI.
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Affiliation(s)
- Patricia Bock
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
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35
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Schlüter A, Espinosa L, Fourcade S, Galino J, López E, Ilieva E, Morató L, Asheuer M, Cook T, McLaren A, Reid J, Kelly F, Bates S, Aubourg P, Galea E, Pujol A. Functional genomic analysis unravels a metabolic-inflammatory interplay in adrenoleukodystrophy. Hum Mol Genet 2011; 21:1062-77. [PMID: 22095690 PMCID: PMC3277307 DOI: 10.1093/hmg/ddr536] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder characterized by axonopathy and demyelination in the central nervous system and adrenal insufficiency. Main X-ALD phenotypes are: (i) an adult adrenomyeloneuropathy (AMN) with axonopathy in spinal cords, (ii) cerebral AMN with brain demyelination (cAMN) and (iii) a childhood variant, cALD, characterized by severe cerebral demyelination. Loss of function of the ABCD1 peroxisomal fatty acid transporter and subsequent accumulation of very-long-chain fatty acids (VLCFAs) are the common culprits to all forms of X-ALD, an aberrant microglial activation accounts for the cerebral forms, whereas inflammation allegedly plays no role in AMN. How VLCFA accumulation leads to neurodegeneration and what factors account for the dissimilar clinical outcomes and prognosis of X-ALD variants remain elusive. To gain insights into these questions, we undertook a transcriptomic approach followed by a functional-enrichment analysis in spinal cords of the animal model of AMN, the Abcd1− null mice, and in normal-appearing white matter of cAMN and cALD patients. We report that the mouse model shares with cAMN and cALD a common signature comprising dysregulation of oxidative phosphorylation, adipocytokine and insulin signaling pathways, and protein synthesis. Functional validation by quantitative polymerase chain reaction, western blots and assays in spinal cord organotypic cultures confirmed the interplay of these pathways through IkB kinase, being VLCFA in excess a causal, upstream trigger promoting the altered signature. We conclude that X-ALD is, in all its variants, a metabolic/inflammatory syndrome, which may offer new targets in X-ALD therapeutics.
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Affiliation(s)
- Agatha Schlüter
- Neurometabolic Diseases Laboratory and Institut de Neuropatologia de Bellvitge, L’Hospitalet de Llobregat, 08908 Barcelona, Spain
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Prominent Microglial Activation in the Early Proinflammatory Immune Response in Naturally Occurring Canine Spinal Cord Injury. J Neuropathol Exp Neurol 2011; 70:703-14. [DOI: 10.1097/nen.0b013e3182270f8e] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Kuzhandaivel A, Nistri A, Mazzone GL, Mladinic M. Molecular Mechanisms Underlying Cell Death in Spinal Networks in Relation to Locomotor Activity After Acute Injury in vitro. Front Cell Neurosci 2011; 5:9. [PMID: 21734866 PMCID: PMC3119860 DOI: 10.3389/fncel.2011.00009] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 06/08/2011] [Indexed: 12/12/2022] Open
Abstract
Understanding the pathophysiological changes triggered by an acute spinal cord injury is a primary goal to prevent and treat chronic disability with a mechanism-based approach. After the primary phase of rapid cell death at the injury site, secondary damage occurs via autodestruction of unscathed tissue through complex cell-death mechanisms that comprise caspase-dependent and caspase-independent pathways. To devise novel neuroprotective strategies to restore locomotion, it is, therefore, necessary to focus on the death mechanisms of neurons and glia within spinal locomotor networks. To this end, the availability of in vitro preparations of the rodent spinal cord capable of expressing locomotor-like oscillatory patterns recorded electrophysiologically from motoneuron pools offers the novel opportunity to correlate locomotor network function with molecular and histological changes long after an acute experimental lesion. Distinct forms of damage to the in vitro spinal cord, namely excitotoxic stimulation or severe metabolic perturbation (with oxidative stress, hypoxia/aglycemia), can be applied with differential outcome in terms of cell types and functional loss. In either case, cell death is a delayed phenomenon developing over several hours. Neurons are more vulnerable to excitotoxicity and more resistant to metabolic perturbation, while the opposite holds true for glia. Neurons mainly die because of hyperactivation of poly(ADP-ribose) polymerase-1 (PARP-1) with subsequent DNA damage and mitochondrial energy collapse. Conversely, glial cells die predominantly by apoptosis. It is likely that early neuroprotection against acute spinal injury may require tailor-made drugs targeted to specific cell-death processes of certain cell types within the locomotor circuitry. Furthermore, comparison of network size and function before and after graded injury provides an estimate of the minimal network membership to express the locomotor program.
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38
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In vitro comparison of motor and sensory neuron outgrowth in a 3D collagen matrix. J Neurosci Methods 2011; 198:53-61. [DOI: 10.1016/j.jneumeth.2011.03.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 02/07/2011] [Accepted: 03/08/2011] [Indexed: 02/01/2023]
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Morrison B, Cullen DK, LaPlaca M. In Vitro Models for Biomechanical Studies of Neural Tissues. NEURAL TISSUE BIOMECHANICS 2011. [DOI: 10.1007/8415_2011_79] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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40
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Lein PJ, Barnhart CD, Pessah IN. Acute hippocampal slice preparation and hippocampal slice cultures. Methods Mol Biol 2011; 758:115-34. [PMID: 21815062 DOI: 10.1007/978-1-61779-170-3_8] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
A major advantage of hippocampal slice preparations is that the cytoarchitecture and synaptic circuits of the hippocampus are largely retained. In neurotoxicology research, organotypic hippocampal slices have mostly been used as acute ex vivo preparations for investigating the effects of neurotoxic chemicals on synaptic function. More recently, hippocampal slice cultures, which can be maintained for several weeks to several months in vitro, have been employed to study how neurotoxic chemicals influence the structural and functional plasticity in hippocampal neurons. This chapter provides protocols for preparing hippocampal slices to be used acutely for electrophysiological measurements using glass microelectrodes or microelectrode arrays or to be cultured for morphometric assessments of individual neurons labeled using biolistics.
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Affiliation(s)
- Pamela J Lein
- Department of Molecular Biosciences, School of Veterinary Medicine and Center for Children's Environmental Health, University of California, Davis, CA, USA.
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41
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Purkinje cell death after uptake of anti-Yo antibodies in cerebellar slice cultures. J Neuropathol Exp Neurol 2010; 69:997-1007. [PMID: 20838245 DOI: 10.1097/nen.0b013e3181f0c82b] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Paraneoplastic cerebellar degeneration accompanying gynecological and breast cancers is characteristically accompanied by a serum and cerebrospinal fluid (CSF) antibody response, termed "anti-Yo," which reacts with cytoplasmic proteins of cerebellar Purkinje cells. Because these antibodies interact with cytoplasmic rather than cell surface membrane proteins, their role in causing Purkinje cell death has been questioned. To address this issue, we studied the interaction of anti-Yo antibodies with Purkinje cells in slice (organotypic) cultures of rat cerebellum. We incubated cultures with immunoglobulin G (IgG)-containing anti-Yo antibodies using titers of anti-Yo antibody equivalent to those found in CSF of affected patients. Cultures were then studied in real time and after fixation for potential uptake of antibody and induction of cell death. Anti-Yo antibodies delivered in serum, CSF, or purified IgG were taken up by viable Purkinje cells, accumulated intracellularly, and were associated with cell death. Normal IgG was also taken up by Purkinje cells but did not accumulate and did not affect cell viability. These findings indicate that autoantibodies directed against intracellular Purkinje cell proteins can be taken up to cause cell death and suggest that anti-Yo antibody may be directly involved in the pathogenesis of paraneoplastic cerebellar degeneration.
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Zhang J, O'Carroll SJ, Wu A, Nicholson LFB, Green CR. A model for ex vivo spinal cord segment culture--a tool for analysis of injury repair strategies. J Neurosci Methods 2010; 192:49-57. [PMID: 20654650 DOI: 10.1016/j.jneumeth.2010.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Revised: 06/18/2010] [Accepted: 07/11/2010] [Indexed: 11/28/2022]
Abstract
Most spinal cord injury research is undertaken using in vivo animal models but the extensive care associated with spinalized animals, inherent variability between animals, and complex surgeries makes alternative models especially valuable. Here we present a novel ex vivo model that enables culture of intact post-natal spinal cord segments for up to five days and the assessment of peripheral nerve grafting repair, enhanced with connexin43 antisense oligodeoxynucleotides (Cx43 AsODN), in this model. Down-regulating Cx43 expression with Cx43 AsODN in cultured spinal cord segments prevents cell death and inhibits inflammation spreading from the site of injury to neighbouring tissue, hence maintaining culture viability. Reduction in segment swelling and improvement in neuron survival were evident after Cx43 AsODN treatment. Furthermore, the combination of Cx43 AsODN with peripheral nerve graft implants into cultured spinal cords promoted axon sprouting from the spinal cord into the peripheral nerve graft. This ex vivo spinal cord segment culture model provides a valuable addition to tools currently available for spinal cord injury research.
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Affiliation(s)
- Jie Zhang
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
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43
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Cho S, Wood A, Bowlby MR. Brain slices as models for neurodegenerative disease and screening platforms to identify novel therapeutics. Curr Neuropharmacol 2010; 5:19-33. [PMID: 18615151 DOI: 10.2174/157015907780077105] [Citation(s) in RCA: 172] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Revised: 12/07/2006] [Accepted: 01/01/2007] [Indexed: 11/22/2022] Open
Abstract
Recent improvements in brain slice technology have made this biological preparation increasingly useful for examining pathophysiology of brain diseases in a tissue context. Brain slices maintain many aspects of in vivo biology, including functional local synaptic circuitry with preserved brain architecture, while allowing good experimental access and precise control of the extracellular environment, making them ideal platforms for dissection of molecular pathways underlying neuronal dysfunction. Importantly, these ex vivo systems permit direct treatment with pharmacological agents modulating these responses and thus provide surrogate therapeutic screening systems without recourse to whole animal studies. Virus or particle mediated transgenic expression can also be accomplished relatively easily to study the function of novel genes in a normal or injured brain tissue context.In this review we will discuss acute brain injury models in organotypic hippocampal and co-culture systems and the effects of pharmacological modulation on neurodegeneration. The review will also cover the evidence of developmental plasticity in these ex vivo models, demonstrating emergence of injury-stimulated neuronal progenitor cells, and neurite sprouting and axonal regeneration following pathway lesioning. Neuro-and axo-genesis are emerging as significant factors contributing to brain repair following many acute and chronic neurodegenerative disorders. Therefore brain slice models may provide a critical contextual experimental system to explore regenerative mechanisms in vitro.
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Affiliation(s)
- Seongeun Cho
- Discovery Neuroscience, Wyeth Research, CN8000, Princeton, NJ 08543, USA.
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Torres B, Silva C, Almeida Á, Caldeira F, Gomes M, Alves E, Silva S, Melo E. Modelo experimental de trauma medular agudo produzido por aparelho estereotáxico modificado. ARQ BRAS MED VET ZOO 2010. [DOI: 10.1590/s0102-09352010000100013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Foram utilizados 55 ratos machos da espécie Rattus novergicus, variedade Wistar, com o objetivo de propor um modelo experimental de trauma medular produzido por aparelho estereotáxico modificado, capaz de reproduzir clinicamente lesões medulares padronizadas. Após realização de laminectomia dorsal de T13, utilizou-se peso compressivo de 50,5g (25 animais - grupo I) ou 70,5g (30 animais - grupo II), durante cinco minutos, comprimindo a medula espinhal. Os animais foram assistidos durante oito dias, por meio de testes comportamentais para avaliar a sensibilidade dolorosa, a capacidade motora, o posicionamento tátil e proprioceptivo e a capacidade de manter-se em plano inclinado. No grupo I, observaram-se déficits neurológicos moderados e transitórios, que variaram entre os animais. No grupo II, foi possível obter um trauma padronizado, caracterizado por paraplegia bilateral e simétrica dos membros posteriores, perda de propriocepção e da sensibilidade dolorosa de todos os animais. A utilização do aparelho estereotáxico desenvolvido permite reproduzir clinicamente trauma medular padronizado em ratos, de maneira simples, econômica e satisfatória, o que poderá proporcionar avanços nas investigações terapêuticas, abrangendo doenças neurodegenerativas, como é o caso do trauma medular agudo.
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45
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Cell death and proliferation in acute slices and organotypic cultures of mammalian CNS. Prog Neurobiol 2009; 88:221-45. [DOI: 10.1016/j.pneurobio.2009.01.002] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 12/09/2008] [Accepted: 01/07/2009] [Indexed: 11/24/2022]
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46
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Systemic polyethylene glycol promotes neurological recovery and tissue sparing in rats after cervical spinal cord injury. J Neuropathol Exp Neurol 2009; 68:661-76. [PMID: 19458542 DOI: 10.1097/nen.0b013e3181a72605] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Polyethylene glycol (PEG) has been reported to possess fusogenic properties that may confer neuroprotection after spinal cord injury (SCI), but there is uncertainty regarding the mechanisms of PEG in vivo and the robustness of its protective effects. We hypothesized that PEG promotes preservation of cytoskeletal proteins associated with white matter protection and neurobehavioral recovery after SCI. In proof-of-principle experiments using a pin-drop organotypic culture model of SCI, PEG attenuated neural cell death. Adult rats underwent 35-g clip compression SCI at C8 and were randomized postinjury to receive intravenous 30% PEG or sterile Ringer's lactate solution. Confocal microscopy and high-performance liquid chromatography of fluorescein-conjugated PEG permitted in vivo quantification of PEG concentrations in the injured and uninjured spinal cord. Western blot, immunohistochemistry, and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling staining demonstrated that PEG reduced 200-kd neurofilament degradation and apoptotic cell death. Polyethylene glycol also promoted spinal cord tissue sparing based on retrograde axonal Fluoro-Gold tracing and morphometric histological assessment. Polyethylene glycol also promoted significant, although modest, neurobehavioral recovery after SCI. Collectively, these results indicate that PEG protects key axonal cytoskeletal proteins after SCI, and that the protection is associated with axonal preservation. The modest extent of locomotor recovery after treatment with PEG suggests, however, that this compound may notconfer sufficient neuroprotection to be used clinically as a single treatment.
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47
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Akhtar AZ, Pippin JJ, Sandusky CB. Animal studies in spinal cord injury: a systematic review of methylprednisolone. Altern Lab Anim 2009; 37:43-62. [PMID: 19292575 DOI: 10.1177/026119290903700108] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The objective of this study was to examine whether animal studies can reliably be used to determine the usefulness of methylprednisolone (MP) and other treatments for acute spinal cord injury (SCI) in humans. This was achieved by performing a systematic review of animal studies on the effects of MP administration on the functional outcome of acute SCI. Data were extracted from the published articles relating to: outcome; MP dosing regimen; species/strain; number of animals; methodological quality; type of injury induction; use of anaesthesia; functional scale used; and duration of follow-up. Subgroup analyses were performed, based on species or strain, injury method, MP dosing regimen, functional outcome measured, and methodological quality. Sixty-two studies were included, which involved a wide variety of animal species and strains. Overall, beneficial effects of MP administration were obtained in 34% of the studies, no effects in 58%, and mixed results in 8%. The results were inconsistent both among and within species, even when attempts were made to detect any patterns in the results through subgroup analyses. The results of this study demonstrate the barriers to the accurate prediction from animal studies of the effectiveness of MP in the treatment of acute SCI in humans. This underscores the need for the development and implementation of validated testing methods.
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Affiliation(s)
- Aysha Z Akhtar
- Physicians Committee for Responsible Medicine, Washington, DC, USA.
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48
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Cho JS, Park HW, Park SK, Roh S, Kang SK, Paik KS, Chang MS. Transplantation of mesenchymal stem cells enhances axonal outgrowth and cell survival in an organotypic spinal cord slice culture. Neurosci Lett 2009; 454:43-8. [DOI: 10.1016/j.neulet.2009.02.024] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 01/21/2009] [Accepted: 02/12/2009] [Indexed: 01/01/2023]
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Rambani K, Vukasinovic J, Glezer A, Potter SM. Culturing thick brain slices: an interstitial 3D microperfusion system for enhanced viability. J Neurosci Methods 2009; 180:243-54. [PMID: 19443039 DOI: 10.1016/j.jneumeth.2009.03.016] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2008] [Revised: 03/18/2009] [Accepted: 03/18/2009] [Indexed: 01/08/2023]
Abstract
Brain slice preparations are well-established models for a wide spectrum of in vitro investigations in the neuroscience discipline. However, these investigations are limited to acute preparations or thin organotypic culture preparations due to the lack of a successful method that allows culturing of thick organotypic brain slices. Thick brain slice cultures suffer necrosis due to ischemia deep in the tissue resulting from a destroyed circulatory system and subsequent diffusion-limited supply of nutrients and oxygen. Although thin organotypic brain slice cultures can be successfully cultured using a well-established roller-tube method (a monolayer organotypic culture) (Gahwiler B H. Organotypic monolayer cultures of nervous tissue. J Neurosci Methods. 1981; 4: 329-342) or a membrane-insert method (up to 1-4 cell layers, <150 microm) (Stoppini L, Buchs PA, Muller D. A simple method for organotypic cultures of neural tissue. J Neurosci Methods 1991; 37: 173-182), these methods fail to support thick tissue preparations. A few perfusion methods (using submerged or interface/microfluidic chambers) have been reported to enhance the longevity (up to few hours) of acute slice preparations (up to 600 microm thick) (Hass HL, Schaerer B, Vosmansky M. A simple perfusion chamber for study of nervous tissue slices in vitro. J Neurosci Methods 1979; 1: 323-325; Nicoll RA, Alger BE. A simple chamber for recording from submerged brain slices. J Neurosci Methods 1981; 4: 153-156; Passeraub PA, Almeida AC, Thakor NV. Design, microfabrication and characterization of a microfluidic chamber for the perfusion of brain tissue slices. J Biomed Dev 2003; 5: 147-155). Here, we report a unique interstitial microfluidic perfusion technique to culture thick (700 microm) organotypic brain slices. The design of the custom-made microperfusion chamber facilitates laminar, interstitial perfusion of oxygenated nutrient medium throughout the tissue thickness with concomitant removal of depleted medium and catabolites. We examined the utility of this perfusion method to enhance the viability of the thick organotypic brain slice cultures after 2 days and 5 days in vitro (DIV). We investigated the range of amenable flow rates that enhance the viability of 700 microm thick organotypic brain slices compared to the unperfused control cultures. Our perfusion method allows up to 84.6% viability (p<0.01) and up to 700 microm thickness, even after 5 DIV. Our results also confirm that these cultures are functionally active and have their in vivo cyto-architecture preserved. Prolonged viability of thick organotypic brain slice cultures will benefit scientists investigating network properties of intact organotypic neuronal networks in a reliable and repeatable manner.
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Affiliation(s)
- Komal Rambani
- Laboratory for Neuroengineering, Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive, NW, Atlanta, GA 30332, USA
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Bakota L, Brandt R. Chapter 2 Live‐Cell Imaging in the Study of Neurodegeneration. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 276:49-103. [DOI: 10.1016/s1937-6448(09)76002-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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