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Charmarke-Askar I, Spenlé C, Bagnard D. Complementary strategies to be used in conjunction with animal models for multiple sclerosis drug discovery: adapting preclinical validation of drug candidates to the need of remyelinating strategies. Expert Opin Drug Discov 2024; 19:1115-1124. [PMID: 39039755 DOI: 10.1080/17460441.2024.2382180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 07/16/2024] [Indexed: 07/24/2024]
Abstract
INTRODUCTION The quest for novel MS therapies focuses on promoting remyelination and neuroprotection, necessitating innovative drug design paradigms and robust preclinical validation methods to ensure efficient clinical translation. The complexity of new drugs action mechanisms is strengthening the need for solid biological validation attempting to address all possible pitfalls and biases precluding access to efficient and safe drugs. AREAS COVERED In this review, the authors describe the different in vitro and in vivo models that should be used to create an integrated approach for preclinical validation of novel drugs, including the evaluation of the action mechanism. This encompasses 2D, 3D in vitro models and animal models presented in such a way to define the appropriate use in a global process of drug screening and hit validation. EXPERT OPINION None of the current available tests allow the concomitant evaluation of anti-inflammatory, immune regulators or remyelinating agents with sufficient reliability. Consequently, the collaborative efforts of academia, industry, and regulatory agencies are essential for establishing standardized protocols, validating novel methodologies, and translating preclinical findings into clinically meaningful outcomes.
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Jagielska A, Radzwill K, Espinosa-Hoyos D, Yang M, Kowsari K, Farley JE, Giera S, Byrne A, Sheng G, Fang NX, Dodge JC, Pedraza CE, Van Vliet KJ. Artificial axons as a biomimetic 3D myelination platform for the discovery and validation of promyelinating compounds. Sci Rep 2023; 13:19529. [PMID: 37945646 PMCID: PMC10636046 DOI: 10.1038/s41598-023-44675-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 10/11/2023] [Indexed: 11/12/2023] Open
Abstract
Multiple sclerosis (MS), a chronic neurodegenerative disease driven by damage to the protective myelin sheath, is currently incurable. Today, all clinically available treatments modulate the immune-mediated symptoms of the disease but they fail to stop neurodegeneration in many patients. Remyelination, the regenerative process of myelin repair by oligodendrocytes, which is considered a necessary step to protect demyelinated axons and stop neuronal death, is impaired in MS patients. One of the major obstacles to finding effective remyelinating drugs is the lack of biomimetic drug screening platforms that enable quantification of compounds' potential to stimulate 3D myelination in the physiologically relevant axon-like environment. To address this need, we built a unique myelination drug discovery platform, by expanding our previously developed technology, artificial axons (AAs), which enables 3D-printing of synthetic axon mimics with the geometry and mechanical properties closely resembling those of biological axons. This platform allows for high-throughput phenotypic myelination assay based on quantification of 3D wrapping of myelin membrane around axons in response to compounds. Here, we demonstrate quantification of 3D myelin wrapping by rat oligodendrocytes around the axon mimics in response to a small library of known pro-myelinating compounds. This assay shows pro-myelinating activity for all tested compounds consistent with the published in vitro and in vivo data, demonstrating predictive power of AA platform. We find that stimulation of myelin wrapping by these compounds is dose-dependent, providing a facile means to quantify the compounds' potency and efficacy in promoting myelin wrapping. Further, the ranking of relative efficacy among these compounds differs in this 3D axon-like environment as compared to a traditional oligodendrocyte 2D differentiation assay quantifying area of deposited myelin membrane. Together, we demonstrate that the artificial axons platform and associated phenotypic myelin wrapping assay afford direct evaluation of myelin wrapping by oligodendrocytes in response to soluble compounds in an axon-like environment, providing a predictive tool for the discovery of remyelinating therapies.
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Affiliation(s)
- Anna Jagielska
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Artificial Axon Labs, Boston, MA, USA.
| | | | - Daniela Espinosa-Hoyos
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Sanofi, Cambridge, MA, USA
| | - Mingyu Yang
- Harvard-MIT Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Kavin Kowsari
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Merck, Rahway, NJ, USA
| | - Jonathan E Farley
- Sanofi, Cambridge, MA, USA
- Alnylam Pharmaceuticals, Cambridge, MA, USA
| | | | | | | | - Nicholas X Fang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- The University of Hong Kong, Hong Kong, China
| | | | | | - Krystyn J Van Vliet
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Cornell University, Ithaca, NY, USA.
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Cakir B, Kiral FR, Park IH. Advanced in vitro models: Microglia in action. Neuron 2022; 110:3444-3457. [PMID: 36327894 DOI: 10.1016/j.neuron.2022.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/28/2022] [Accepted: 10/04/2022] [Indexed: 11/05/2022]
Abstract
In the central nervous system (CNS), microglia carry out multiple tasks related to brain development, maintenance of brain homeostasis, and function of the CNS. Recent advanced in vitro model systems allow us to perform more detailed and specific analyses of microglial functions in the CNS. The development of human pluripotent stem cells (hPSCs)-based 2D and 3D cell culture methods, particularly advancements in brain organoid models, offers a better platform to dissect microglial function in various contexts. Despite the improvement of these methods, there are still definite restrictions. Understanding their drawbacks and benefits ensures their proper use. In this primer, we review current developments regarding in vitro microglial production and characterization and their use to address fundamental questions about microglial function in healthy and diseased states, and we discuss potential future improvements with a particular emphasis on brain organoid models.
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Affiliation(s)
- Bilal Cakir
- Department of Genetics, Yale Stem Cell Center, Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA.
| | - Ferdi Ridvan Kiral
- Department of Genetics, Yale Stem Cell Center, Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - In-Hyun Park
- Department of Genetics, Yale Stem Cell Center, Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA.
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Aktories P, Petry P, Kierdorf K. Microglia in a Dish—Which Techniques Are on the Menu for Functional Studies? Front Cell Neurosci 2022; 16:908315. [PMID: 35722614 PMCID: PMC9204042 DOI: 10.3389/fncel.2022.908315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 05/11/2022] [Indexed: 12/12/2022] Open
Abstract
Microglia build the first line of defense in the central nervous system (CNS) and play central roles during development and homeostasis. Indeed, they serve a plethora of diverse functions in the CNS of which many are not yet fully described and more are still to be discovered. Research of the last decades unraveled an implication of microglia in nearly every neurodegenerative and neuroinflammatory disease, making it even more challenging to elucidate molecular mechanisms behind microglial functions and to modulate aberrant microglial behavior. To understand microglial functions and the underlying signaling machinery, many attempts were made to employ functional in vitro studies of microglia. However, the range of available cell culture models is wide and they come with different advantages and disadvantages for functional assays. Here we aim to provide a condensed summary of common microglia in vitro systems and discuss their potentials and shortcomings for functional studies in vitro.
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Affiliation(s)
- Philipp Aktories
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Philippe Petry
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Katrin Kierdorf
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
- CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- *Correspondence: Katrin Kierdorf
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Scalabrino G. Newly Identified Deficiencies in the Multiple Sclerosis Central Nervous System and Their Impact on the Remyelination Failure. Biomedicines 2022; 10:biomedicines10040815. [PMID: 35453565 PMCID: PMC9026986 DOI: 10.3390/biomedicines10040815] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/18/2022] [Accepted: 03/21/2022] [Indexed: 12/14/2022] Open
Abstract
The pathogenesis of multiple sclerosis (MS) remains enigmatic and controversial. Myelin sheaths in the central nervous system (CNS) insulate axons and allow saltatory nerve conduction. MS brings about the destruction of myelin sheaths and the myelin-producing oligodendrocytes (ODCs). The conundrum of remyelination failure is, therefore, crucial in MS. In this review, the roles of epidermal growth factor (EGF), normal prions, and cobalamin in CNS myelinogenesis are briefly summarized. Thereafter, some findings of other authors and ourselves on MS and MS-like models are recapitulated, because they have shown that: (a) EGF is significantly decreased in the CNS of living or deceased MS patients; (b) its repeated administration to mice in various MS-models prevents demyelination and inflammatory reaction; (c) as was the case for EGF, normal prion levels are decreased in the MS CNS, with a strong correspondence between liquid and tissue levels; and (d) MS cobalamin levels are increased in the cerebrospinal fluid, but decreased in the spinal cord. In fact, no remyelination can occur in MS if these molecules (essential for any form of CNS myelination) are lacking. Lastly, other non-immunological MS abnormalities are reviewed. Together, these results have led to a critical reassessment of MS pathogenesis, partly because EGF has little or no role in immunology.
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Affiliation(s)
- Giuseppe Scalabrino
- Department of Biomedical Sciences for Health, University of Milan, 20133 Milan, Italy
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Marangon D, Caporale N, Boccazzi M, Abbracchio MP, Testa G, Lecca D. Novel in vitro Experimental Approaches to Study Myelination and Remyelination in the Central Nervous System. Front Cell Neurosci 2021; 15:748849. [PMID: 34720882 PMCID: PMC8551863 DOI: 10.3389/fncel.2021.748849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/22/2021] [Indexed: 12/15/2022] Open
Abstract
Myelin is the lipidic insulating structure enwrapping axons and allowing fast saltatory nerve conduction. In the central nervous system, myelin sheath is the result of the complex packaging of multilamellar extensions of oligodendrocyte (OL) membranes. Before reaching myelinating capabilities, OLs undergo a very precise program of differentiation and maturation that starts from OL precursor cells (OPCs). In the last 20 years, the biology of OPCs and their behavior under pathological conditions have been studied through several experimental models. When co-cultured with neurons, OPCs undergo terminal maturation and produce myelin tracts around axons, allowing to investigate myelination in response to exogenous stimuli in a very simple in vitro system. On the other hand, in vivo models more closely reproducing some of the features of human pathophysiology enabled to assess the consequences of demyelination and the molecular mechanisms of remyelination, and they are often used to validate the effect of pharmacological agents. However, they are very complex, and not suitable for large scale drug discovery screening. Recent advances in cell reprogramming, biophysics and bioengineering have allowed impressive improvements in the methodological approaches to study brain physiology and myelination. Rat and mouse OPCs can be replaced by human OPCs obtained by induced pluripotent stem cells (iPSCs) derived from healthy or diseased individuals, thus offering unprecedented possibilities for personalized disease modeling and treatment. OPCs and neural cells can be also artificially assembled, using 3D-printed culture chambers and biomaterial scaffolds, which allow modeling cell-to-cell interactions in a highly controlled manner. Interestingly, scaffold stiffness can be adopted to reproduce the mechanosensory properties assumed by tissues in physiological or pathological conditions. Moreover, the recent development of iPSC-derived 3D brain cultures, called organoids, has made it possible to study key aspects of embryonic brain development, such as neuronal differentiation, maturation and network formation in temporal dynamics that are inaccessible to traditional in vitro cultures. Despite the huge potential of organoids, their application to myelination studies is still in its infancy. In this review, we shall summarize the novel most relevant experimental approaches and their implications for the identification of remyelinating agents for human diseases such as multiple sclerosis.
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Affiliation(s)
- Davide Marangon
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Nicolò Caporale
- Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
- Human Technopole, Milan, Italy
| | - Marta Boccazzi
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Maria P. Abbracchio
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Giuseppe Testa
- Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
- Human Technopole, Milan, Italy
| | - Davide Lecca
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
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Assessing the Potential of Molecular Imaging for Myelin Quantification in Organotypic Cultures. Pharmaceutics 2021; 13:pharmaceutics13070975. [PMID: 34203246 PMCID: PMC8309097 DOI: 10.3390/pharmaceutics13070975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/22/2021] [Accepted: 06/22/2021] [Indexed: 11/17/2022] Open
Abstract
Ex vivo models for the noninvasive study of myelin-related diseases represent an essential tool to understand the mechanisms of diseases and develop therapies against them. Herein, we assessed the potential of multimodal imaging traceable myelin-targeting liposomes to quantify myelin in organotypic cultures. Methods: MRI testing was used to image mouse cerebellar tissue sections and organotypic cultures. Demyelination was induced by lysolecithin treatment. Myelin-targeting liposomes were synthetized and characterized, and their capacity to quantify myelin was tested by fluorescence imaging. Results: Imaging of freshly excised tissue sections ranging from 300 µm to 1 mm in thickness was achieved with good contrast between white (WM) and gray matter (GM) using T2w MRI. The typical loss of stiffness, WM structures, and thickness of organotypic cultures required the use of diffusion-weighted methods. Designed myelin-targeting liposomes allowed for semiquantitative detection by fluorescence, but the specificity for myelin was not consistent between assays due to the unspecific binding of liposomes. Conclusions: With respect to the sensitivity, imaging of brain tissue sections and organotypic cultures by MRI is feasible, and myelin-targeting nanosystems are a promising solution to quantify myelin ex vivo. With respect to specificity, fine tuning of the probe is required. Lipid-based systems may not be suitable for this goal, due to unspecific binding to tissues.
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Baudouin L, Adès N, Kanté K, Czarnecki A, Bachelin C, Baskaran A, Langui D, Millécamps A, Gurchenkov B, Velut Y, Duarte K, Barnier JV, Nait Oumesmar B, Bouslama-Oueghlani L. Co-culture of exogenous oligodendrocytes with unmyelinated cerebella: Revisiting ex vivo models and new tools to study myelination. Glia 2021; 69:1916-1931. [PMID: 33811384 DOI: 10.1002/glia.24001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/15/2021] [Accepted: 03/18/2021] [Indexed: 12/20/2022]
Abstract
Common in vitro models used to study the mechanisms regulating myelination rely on co-cultures of oligodendrocyte precursor cells (OPCs) and neurons. In such models, myelination occurs in an environment that does not fully reflect cell-cell interactions and environmental cues present in vivo. To avoid these limitations while specifically manipulating oligodendroglial cells, we developed a reliable ex vivo model of myelination by seeding OPCs on cerebellar slices, deprived of their endogenous oligodendrocytes. We showed that exogenous OPCs seeded on unmyelinated cerebella, efficiently differentiate and form compact myelin. Spectral confocal reflectance microscopy and electron microscopy analysis revealed that the density of compacted myelin sheaths highly increases all along the culture. Importantly, we defined the appropriate culture time frame to study OPC differentiation and myelination, using accurate quantification resources we generated. Thus, this model is a powerful tool to study the cellular and molecular mechanisms of OPC differentiation and myelination. Moreover, it is suitable for the development and validation of new therapies for myelin-related disorders such as multiple sclerosis and psychiatric diseases.
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Affiliation(s)
- Lucas Baudouin
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, Sorbonne Université, Paris, France
| | - Noémie Adès
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, Sorbonne Université, Paris, France
| | - Kadia Kanté
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, Sorbonne Université, Paris, France
| | - Antonny Czarnecki
- INSERM, UMR_S 1130, CNRS, UMR 8246, Neuroscience Paris Seine, Institute of Biology Paris Seine, Sorbonne University, Paris, France
| | - Corinne Bachelin
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, Sorbonne Université, Paris, France
| | - Asha Baskaran
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, ICM Quant, Sorbonne Université, Paris, France
| | - Dominique Langui
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, ICM Quant, Sorbonne Université, Paris, France
| | - Aymeric Millécamps
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, ICM Quant, Sorbonne Université, Paris, France
| | - Basile Gurchenkov
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, ICM Quant, Sorbonne Université, Paris, France
| | - Yoan Velut
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université de Paris, Paris, France
| | - Kévin Duarte
- Paris-Saclay Neuroscience Institute (Neuro-PSI), UMR 9197, CNRS, University of Paris-Sud, University of Paris-Saclay, Orsay, France
| | - Jean-Vianney Barnier
- Paris-Saclay Neuroscience Institute (Neuro-PSI), UMR 9197, CNRS, University of Paris-Sud, University of Paris-Saclay, Orsay, France
| | - Brahim Nait Oumesmar
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, Sorbonne Université, Paris, France
| | - Lamia Bouslama-Oueghlani
- Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, Sorbonne Université, Paris, France
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de Oliveira LG, Angelo YDS, Iglesias AH, Peron JPS. Unraveling the Link Between Mitochondrial Dynamics and Neuroinflammation. Front Immunol 2021; 12:624919. [PMID: 33796100 PMCID: PMC8007920 DOI: 10.3389/fimmu.2021.624919] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 02/25/2021] [Indexed: 12/13/2022] Open
Abstract
Neuroinflammatory and neurodegenerative diseases are a major public health problem worldwide, especially with the increase of life-expectancy observed during the last decades. For many of these diseases, we still lack a full understanding of their etiology and pathophysiology. Nonetheless their association with mitochondrial dysfunction highlights this organelle as an important player during CNS homeostasis and disease. Markers of Parkinson (PD) and Alzheimer (AD) diseases are able to induce innate immune pathways induced by alterations in mitochondrial Ca2+ homeostasis leading to neuroinflammation. Additionally, exacerbated type I IFN responses triggered by mitochondrial DNA (mtDNA), failures in mitophagy, ER-mitochondria communication and mtROS production promote neurodegeneration. On the other hand, regulation of mitochondrial dynamics is essential for CNS health maintenance and leading to the induction of IL-10 and reduction of TNF-α secretion, increased cell viability and diminished cell injury in addition to reduced oxidative stress. Thus, although previously solely seen as power suppliers to organelles and molecular processes, it is now well established that mitochondria have many other important roles, including during immune responses. Here, we discuss the importance of these mitochondrial dynamics during neuroinflammation, and how they correlate either with the amelioration or worsening of CNS disease.
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Affiliation(s)
- Lilian Gomes de Oliveira
- Neuroimmune Interactions Laboratory, Immunology Department - Institute of Biomedical Sciences (ICB) IV, University of São Paulo (USP), São Paulo, Brazil
- Neuroimmunology of Arboviruses Laboratory, Scientific Platform Pasteur-USP, University of São Paulo (USP), São Paulo, Brazil
| | - Yan de Souza Angelo
- Neuroimmune Interactions Laboratory, Immunology Department - Institute of Biomedical Sciences (ICB) IV, University of São Paulo (USP), São Paulo, Brazil
- Neuroimmunology of Arboviruses Laboratory, Scientific Platform Pasteur-USP, University of São Paulo (USP), São Paulo, Brazil
| | - Antonio H Iglesias
- Loyola University Medical Center, Stritch School of Medicine, Loyola University Chicago, Chicago, IL, United States
| | - Jean Pierre Schatzmann Peron
- Neuroimmune Interactions Laboratory, Immunology Department - Institute of Biomedical Sciences (ICB) IV, University of São Paulo (USP), São Paulo, Brazil
- Neuroimmunology of Arboviruses Laboratory, Scientific Platform Pasteur-USP, University of São Paulo (USP), São Paulo, Brazil
- Loyola University Medical Center, Stritch School of Medicine, Loyola University Chicago, Chicago, IL, United States
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Tian C, Li S, He L, Han X, Tang F, Huang R, Lin Z, Deng S, Xu J, Huang H, Zhao H, Li Z. Transient receptor potential ankyrin 1 contributes to the lysophosphatidylcholine-induced oxidative stress and cytotoxicity in OLN-93 oligodendrocyte. Cell Stress Chaperones 2020; 25:955-968. [PMID: 32572784 PMCID: PMC7591684 DOI: 10.1007/s12192-020-01131-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/22/2020] [Accepted: 06/17/2020] [Indexed: 12/13/2022] Open
Abstract
Transient receptor potential ankyrin 1 (TRPA1), the non-selective cation channel, was found that can mediate the generation of multiple sclerosis, while the mechanism is still controversial. Lysophosphatidylcholine (LPC) is a critical trigger of multiple sclerosis which results from the syndrome of neuronal inflammation and demyelination. In this work, we suggested that TRPA1 can mediate the LPC-induced oxidative stress and cytotoxicity in OLN-93 oligodendrocyte. The expression of TRPA1 in OLN-93 was detected by using quantitative real-time PCR (qRT-PCR) and immunofluorescence. The calcium overload induced by LPC via TRPA1 was detected by calcium imaging. The mechanism of LPC-induced mitochondrial reactive oxygen species (mtROS) generation, mitochondria membrane depolarization, nitric oxide (NO) increase, and development of superoxide production via TRPA1 was verified by using confocal imaging. The cell injury elicited by LPC via TRPA1 was confirmed by both CCK-8 and LDH cytotoxicity detection. These results indicate that TRPA1 plays an important role of the LPC-induced oxidative stress and cell damage in OLN-93 oligodendrocyte. Therefore, inhibition of TRPA1 may protect the LPC-induced demyelination.
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Affiliation(s)
- Chao Tian
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Guangzhou JYK Biotechnology Company Limited, Guangzhou, Guangdong, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China
| | - Shuai Li
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China
| | - Lang He
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xiaobo Han
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China
| | - Feng Tang
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Guangzhou JYK Biotechnology Company Limited, Guangzhou, Guangdong, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China
| | - Rongqi Huang
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China
| | - Zuoxian Lin
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China
| | - Sihao Deng
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, China
| | - Junjie Xu
- Guangzhou JYK Biotechnology Company Limited, Guangzhou, Guangdong, China
| | - Hualin Huang
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China
| | - Huifang Zhao
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China
| | - Zhiyuan Li
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong, China.
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, China.
- Guangzhou JYK Biotechnology Company Limited, Guangzhou, Guangdong, China.
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, Guangdong, China.
- GZMU-GIBH Joint School of Life Sciences, Guangzhou Medical University, Guangzhou, Guangdong, China.
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11
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Tian Z, Chu T, Shields LBE, Zhu Q, Zhang YP, Kong M, Barnes GN, Wang Y, Shields CB, Cai J. Platelet-Activating Factor Deteriorates Lysophosphatidylcholine-Induced Demyelination Via Its Receptor-Dependent and -Independent Effects. Mol Neurobiol 2020; 57:4069-4081. [PMID: 32661728 DOI: 10.1007/s12035-020-02003-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 06/26/2020] [Indexed: 11/30/2022]
Abstract
Accumulating evidence suggests that platelet-activating factor (PAF) increases the inflammatory response in demyelinating diseases such as multiple sclerosis. However, PAF receptor (PAFR) antagonists do not show therapeutic efficacy for MS, and its underlying mechanisms remain poorly understood. In the present study, we investigated the effects of PAF on an ex vivo demyelination cerebellar model following lysophosphatidylcholine (LPC, 0.5 mg/mL) application using wild-type and PAFR conventional knockout (PAFR-KO) mice. Demyelination was induced in cerebellar slices that were cultured with LPC for 18 h. Exogenous PAF (1 μM) acting on cerebellar slices alone did not cause demyelination but increased the severity of LPC-induced demyelination in both wild-type and PAFR-KO mice. LPC inhibited the expression of PAF-AH, MBP, TNF-α, and TGF-β1 but facilitated the expression of IL-1β and IL-6 in wild-type preparations. Of note, exogenous PAF stimulated microglial activation in both wild-type and PAFR-KO mice. The subsequent inflammatory cytokines TNFα, IL-1β, and IL-6 as well as the anti-inflammatory cytokine TGF-β1 demonstrated a diverse transcriptional profile with or without LPC treatment. PAF promoted TNF-α expression and suppressed TGF-β1 expression indiscriminately in wild-type and knockout slices; however, transcription of IL-1β and IL-6 was not significantly affected in both slices. The syntheses of IL-1β and IL-6 were significantly increased in LPC-induced demyelination preparations without PAF but showed a redundancy in PAF-treated wild-type and knockout slices. These data suggest that PAF can play a detrimental role in LPC-induced demyelination probably due to a redundant response of PAFR-dependent and PAFR-independent effects on inflammatory cytokines.
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Affiliation(s)
- Zhisen Tian
- Department of Orthopedics, China-Japan Union Hospital of Jilin University, Changchun, 130033, People's Republic of China.,Pediatric Research Institute, Department of Pediatrics, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Tianci Chu
- Pediatric Research Institute, Department of Pediatrics, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Lisa B E Shields
- Norton Neuroscience Institute, Norton Healthcare, Louisville, KY, 40202, USA
| | - Qingsan Zhu
- Department of Orthopedics, China-Japan Union Hospital of Jilin University, Changchun, 130033, People's Republic of China.
| | - Yi Ping Zhang
- Norton Neuroscience Institute, Norton Healthcare, Louisville, KY, 40202, USA
| | - Maiying Kong
- Department of Bioinformatics and Biostatistics, University of Louisville School of Public Health & Information Sciences, Louisville, KY, 40202, USA
| | - Gregory N Barnes
- Pediatric Research Institute, Department of Pediatrics, University of Louisville School of Medicine, Louisville, KY, 40202, USA.,Department of Neurology, University of Louisville School of Medicine, Louisville, KY, 40202, USA.,Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Yuanyi Wang
- Department of Spine Surgery, The First Hospital of Jilin University, Changchun, 130021, People's Republic of China.
| | - Christopher B Shields
- Norton Neuroscience Institute, Norton Healthcare, Louisville, KY, 40202, USA.,Department of Neurosurgery, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Jun Cai
- Pediatric Research Institute, Department of Pediatrics, University of Louisville School of Medicine, Louisville, KY, 40202, USA. .,Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
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12
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Zhang Y, Li X, Ciric B, Curtis MT, Chen WJ, Rostami A, Zhang GX. A dual effect of ursolic acid to the treatment of multiple sclerosis through both immunomodulation and direct remyelination. Proc Natl Acad Sci U S A 2020; 117:9082-9093. [PMID: 32253301 PMCID: PMC7183235 DOI: 10.1073/pnas.2000208117] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Current multiple sclerosis (MS) medications are mainly immunomodulatory, having little or no effect on neuroregeneration of damaged central nervous system (CNS) tissue; they are thus primarily effective at the acute stage of disease, but much less so at the chronic stage. An MS therapy that has both immunomodulatory and neuroregenerative effects would be highly beneficial. Using multiple in vivo and in vitro strategies, in the present study we demonstrate that ursolic acid (UA), an antiinflammatory natural triterpenoid, also directly promotes oligodendrocyte maturation and CNS myelin repair. Oral treatment with UA significantly decreased disease severity and CNS inflammation and demyelination in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. Importantly, remyelination and neural repair in the CNS were observed even after UA treatment was started on day 60 post immunization when EAE mice had full-blown demyelination and axonal damage. UA treatment also enhanced remyelination in a cuprizone-induced demyelination model in vivo and brain organotypic slice cultures ex vivo and promoted oligodendrocyte maturation in vitro, indicating a direct myelinating capacity. Mechanistically, UA induced promyelinating neurotrophic factor CNTF in astrocytes by peroxisome proliferator-activated receptor γ(PPARγ)/CREB signaling, as well as by up-regulation of myelin-related gene expression during oligodendrocyte maturation via PPARγ activation. Together, our findings demonstrate that UA has significant potential as an oral antiinflammatory and neural repair agent for MS, especially at the chronic-progressive stage.
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Affiliation(s)
- Yuan Zhang
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19107
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Xing Li
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19107
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Bogoljub Ciric
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19107
| | - Mark T Curtis
- Department of Pathology, Thomas Jefferson University, Philadelphia, PA 19107
| | - Wan-Jun Chen
- Mucosal Immunology Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892
| | | | - Guang-Xian Zhang
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19107;
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13
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Makhija EP, Espinosa-Hoyos D, Jagielska A, Van Vliet KJ. Mechanical regulation of oligodendrocyte biology. Neurosci Lett 2019; 717:134673. [PMID: 31838017 DOI: 10.1016/j.neulet.2019.134673] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 11/25/2019] [Accepted: 12/01/2019] [Indexed: 12/27/2022]
Abstract
Oligodendrocytes (OL) are a subset of glial cells in the central nervous system (CNS) comprising the brain and spinal cord. The CNS environment is defined by complex biochemical and biophysical cues during development and response to injury or disease. In the last decade, significant progress has been made in understanding some of the key biophysical factors in the CNS that modulate OL biology, including their key role in myelination of neurons. Taken together, those studies offer translational implications for remyelination therapies, pharmacological research, identification of novel drug targets, and improvements in methods to generate human oligodendrocyte progenitor cells (OPCs) and OLs from donor stem cells in vitro. This review summarizes current knowledge of how various physical and mechanical cues affect OL biology and its implications for disease, therapeutic approaches, and generation of human OPCs and OLs.
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Affiliation(s)
- Ekta P Makhija
- BioSystems & Micromechanics (BioSyM) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, Singapore 138602; Critical Analytics for Manufacturing Personalized-Medicine (CAMP) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, 138602, Singapore
| | - Daniela Espinosa-Hoyos
- BioSystems & Micromechanics (BioSyM) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, Singapore 138602; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Anna Jagielska
- BioSystems & Micromechanics (BioSyM) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, Singapore 138602; Department of Materials Science & Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA.
| | - Krystyn J Van Vliet
- BioSystems & Micromechanics (BioSyM) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, Singapore 138602; Critical Analytics for Manufacturing Personalized-Medicine (CAMP) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, 138602, Singapore; Department of Materials Science & Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA.
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14
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Rivera FJ, de la Fuente AG, Zhao C, Silva ME, Gonzalez GA, Wodnar R, Feichtner M, Lange S, Errea O, Priglinger E, O'Sullivan A, Romanelli P, Jadasz JJ, Brachtl G, Greil R, Tempfer H, Traweger A, Bátiz LF, Küry P, Couillard‐Despres S, Franklin RJM, Aigner L. Aging restricts the ability of mesenchymal stem cells to promote the generation of oligodendrocytes during remyelination. Glia 2019; 67:1510-1525. [PMID: 31038798 PMCID: PMC6618006 DOI: 10.1002/glia.23624] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 03/26/2019] [Accepted: 03/29/2019] [Indexed: 12/17/2022]
Abstract
Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) that leads to severe neurological deficits. Due to their immunomodulatory and neuroprotective activities and their ability to promote the generation of oligodendrocytes, mesenchymal stem cells (MSCs) are currently being developed for autologous cell therapy in MS. As aging reduces the regenerative capacity of all tissues, it is of relevance to investigate whether MSCs retain their pro-oligodendrogenic activity with increasing age. We demonstrate that MSCs derived from aged rats have a reduced capacity to induce oligodendrocyte differentiation of adult CNS stem/progenitor cells. Aging also abolished the ability of MSCs to enhance the generation of myelin-like sheaths in demyelinated cerebellar slice cultures. Finally, in a rat model for CNS demyelination, aging suppressed the capability of systemically transplanted MSCs to boost oligodendrocyte progenitor cell (OPC) differentiation during remyelination. Thus, aging restricts the ability of MSCs to support the generation of oligodendrocytes and consequently inhibits their capacity to enhance the generation of myelin-like sheaths. These findings may impact on the design of therapies using autologous MSCs in older MS patients.
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Affiliation(s)
- Francisco J. Rivera
- Laboratory of Stem Cells and Neuroregeneration, Institute of Anatomy, Histology and PathologyFaculty of Medicine, Universidad Austral de ChileValdiviaChile
- Center for Interdisciplinary Studies on the Nervous System (CISNe)Universidad Austral de ChileValdiviaChile
- Institute of Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
- Wellcome‐MRC Cambridge Stem Cell Institute & Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Alerie G. de la Fuente
- Wellcome‐MRC Cambridge Stem Cell Institute & Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Chao Zhao
- Wellcome‐MRC Cambridge Stem Cell Institute & Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Maria E. Silva
- Laboratory of Stem Cells and Neuroregeneration, Institute of Anatomy, Histology and PathologyFaculty of Medicine, Universidad Austral de ChileValdiviaChile
- Center for Interdisciplinary Studies on the Nervous System (CISNe)Universidad Austral de ChileValdiviaChile
- Institute of Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
- Wellcome‐MRC Cambridge Stem Cell Institute & Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
- Institute of Pharmacy, Faculty of SciencesUniversidad Austral de ChileValdiviaChile
| | - Ginez A. Gonzalez
- Wellcome‐MRC Cambridge Stem Cell Institute & Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Roman Wodnar
- Institute of Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
| | - Martina Feichtner
- Institute of Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
| | - Simona Lange
- Institute of Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
| | - Oihana Errea
- Wellcome‐MRC Cambridge Stem Cell Institute & Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Eleni Priglinger
- Institute of Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
- Ludwig Boltzmann Institute for Experimental and Clinical TraumatologyAUVA Research CenterLinz/ViennaAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
| | - Anna O'Sullivan
- Institute of Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
- Institute of Experimental NeuroregenerationParacelsus Medical University SalzburgSalzburgAustria
| | - Pasquale Romanelli
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
- Institute of Experimental NeuroregenerationParacelsus Medical University SalzburgSalzburgAustria
| | - Janusz J. Jadasz
- Laboratory of Experimental Ophthalmology, Department of OphthalmologyUniversity Hospital Düsseldorf, Heinrich‐Heine‐UniversityDüsseldorfGermany
| | - Gabriele Brachtl
- Laboratory for Immunological and Molecular Cancer Research, 3rd Medical Department for Hematology, Medical Oncology, Hemostasiology, Infectious Diseases, and RheumatologyFederal Hospital of Salzburg and Paracelsus Medical UniversitySalzburgAustria
- Experimental and Clinical Cell Therapy InstituteParacelsus Medical UniversitySalzburgAustria
| | - Richard Greil
- Laboratory for Immunological and Molecular Cancer Research, 3rd Medical Department for Hematology, Medical Oncology, Hemostasiology, Infectious Diseases, and RheumatologyFederal Hospital of Salzburg and Paracelsus Medical UniversitySalzburgAustria
| | - Herbert Tempfer
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
- Institute of Tendon and Bone RegenerationParacelsus Medical UniversitySalzburgAustria
| | - Andreas Traweger
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
- Institute of Tendon and Bone RegenerationParacelsus Medical UniversitySalzburgAustria
| | - Luis F. Bátiz
- Center for Interdisciplinary Studies on the Nervous System (CISNe)Universidad Austral de ChileValdiviaChile
- Centro de Investigación Biomédica (CIB), Facultad de MedicinaUniversidad de los AndesSantiagoChile
| | - Patrick Küry
- Department of Neurology, Medical FacultyHeinrich‐Heine‐UniversityDüsseldorfGermany
| | - Sebastien Couillard‐Despres
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
- Institute of Experimental NeuroregenerationParacelsus Medical University SalzburgSalzburgAustria
| | - Robin J. M. Franklin
- Wellcome‐MRC Cambridge Stem Cell Institute & Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Ludwig Aigner
- Institute of Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI‐TReCS)Paracelsus Medical UniversitySalzburgAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
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15
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Abstract
The preparation of oligodendrocytes and neurons independently in vitro has provided substantial insight into the biology of the process of myelin sheath formation. This chapter describes a myelination system of dorsal root ganglion neurons by independent isolation of oligodendrocyte progenitor cells from either rat or mouse cortex. This in vitro assay can be used to examine the molecular determinants of myelin sheath formation.
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Affiliation(s)
- Matthew Swire
- MRC Centre for Regenerative Medicine, The Multiple Sclerosis Research Centre, The University of Edinburgh, Edinburgh, UK.
| | - Charles Ffrench-Constant
- MRC Centre for Regenerative Medicine, The Multiple Sclerosis Research Centre, The University of Edinburgh, Edinburgh, UK
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16
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Xu YKT, Chitsaz D, Brown RA, Cui QL, Dabarno MA, Antel JP, Kennedy TE. Deep learning for high-throughput quantification of oligodendrocyte ensheathment at single-cell resolution. Commun Biol 2019; 2:116. [PMID: 30937398 PMCID: PMC6435748 DOI: 10.1038/s42003-019-0356-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 01/30/2019] [Indexed: 01/20/2023] Open
Abstract
High-throughput quantification of oligodendrocyte myelination is a challenge that, if addressed, would facilitate the development of therapeutics to promote myelin protection and repair. Here, we established a high-throughput method to assess oligodendrocyte ensheathment in-vitro, combining nanofiber culture devices and automated imaging with a heuristic approach that informed the development of a deep learning analytic algorithm. The heuristic approach was developed by modeling general characteristics of oligodendrocyte ensheathments, while the deep learning neural network employed a UNet architecture and a single-cell training method to associate ensheathed segments with individual oligodendrocytes. Reliable extraction of multiple morphological parameters from individual cells, without heuristic approximations, allowed the UNet to match the accuracy of expert-human measurements. The capacity of this technology to perform multi-parametric analyses at the level of individual cells, while reducing manual labor and eliminating human variability, permits the detection of nuanced cellular differences to accelerate the discovery of new insights into oligodendrocyte physiology.
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Affiliation(s)
- Yu Kang T. Xu
- McGill Program in Neuroengineering, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, H3A 2B4 Montreal, QC Canada
| | - Daryan Chitsaz
- McGill Program in Neuroengineering, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, H3A 2B4 Montreal, QC Canada
| | - Robert A. Brown
- McGill Program in Neuroengineering, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, H3A 2B4 Montreal, QC Canada
| | - Qiao Ling Cui
- McGill Program in Neuroengineering, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, H3A 2B4 Montreal, QC Canada
| | - Matthew A. Dabarno
- McGill Program in Neuroengineering, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, H3A 2B4 Montreal, QC Canada
| | - Jack P. Antel
- McGill Program in Neuroengineering, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, H3A 2B4 Montreal, QC Canada
| | - Timothy E. Kennedy
- McGill Program in Neuroengineering, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, H3A 2B4 Montreal, QC Canada
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17
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Zhang Y, Lu XY, Ye ZQ, Ciric B, Ma CG, Rostami A, Li X, Zhang GX. Combination Therapy With Fingolimod and Neural Stem Cells Promotes Functional Myelination in vivo Through a Non-immunomodulatory Mechanism. Front Cell Neurosci 2019; 13:14. [PMID: 30804753 PMCID: PMC6371042 DOI: 10.3389/fncel.2019.00014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 01/15/2019] [Indexed: 01/03/2023] Open
Abstract
Myelination, which occurs predominantly postnatally and continues throughout life, is important for proper neurologic function of the mammalian central nervous system (CNS). We have previously demonstrated that the combination therapy of fingolimod (FTY720) and transplanted neural stem cells (NSCs) had a significantly enhanced therapeutic effect on the chronic stage of experimental autoimmune encephalomyelitis, an animal model of CNS autoimmunity, compared to using either one of them alone. However, reduced disease severity may be secondary to the immunomodulatory effects of FTY720 and NSCs, while whether this therapy directly affects myelinogenesis remains unknown. To investigate this important question, we used three myelination models under minimal or non-inflammatory microenvironments. Our results showed that FTY720 drives NSCs to differentiate into oligodendrocytes and promotes myelination in an ex vivo brain slice culture model, and in the developing CNS of healthy postnatal mice in vivo. Elevated levels of neurotrophic factors, e.g., brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor, were observed in the CNS of the treated infant mice. Further, FTY720 and NSCs efficiently prolonged the survival and improved sensorimotor function of shiverer mice. Together, these data demonstrate a direct effect of FTY720, beyond its known immunomodulatory capacity, in NSC differentiation and myelin development as a novel mechanism underlying its therapeutic effect in demyelinating diseases.
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Affiliation(s)
- Yuan Zhang
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, United States,National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, Shaanxi Normal University, Xi'an, China
| | - Xin-Yu Lu
- National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, Shaanxi Normal University, Xi'an, China
| | - Ze-Qin Ye
- National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, Shaanxi Normal University, Xi'an, China
| | - Bogoljub Ciric
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, United States
| | - Cun-Gen Ma
- Department of Neurology, Institute of Brain Science, Shanxi Datong University Medical School, Datong, China
| | - Abdolmohamad Rostami
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, United States
| | - Xing Li
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, United States,National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, Shaanxi Normal University, Xi'an, China,*Correspondence: Xing Li
| | - Guang-Xian Zhang
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, United States,Guang-Xian Zhang
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18
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Abstract
Important advances in our understanding of oligodendrocyte precursor cell biology and differentiation have stemmed from in vitro experiments using cultures of isolated primary oligodendrocyte precursor cells. To examine the process of myelination in the final stages of oligodendrocyte development, experimental systems have previously been limited to models utilizing neurons. Recent advances in three-dimensional culture systems, however, have opened the possibility to observe myelin sheath formation with only one cell type, the oligodendrocyte precursor cell. In this chapter, such a method is described for examining oligodendrocyte myelin sheath formation with isolated oligodendrocytes in the absence of neurons. This assay is ideal for gaining mechanistic insight into oligodendrocyte-specific regulation of myelin sheath formation. Oligodendrocyte heterogeneity can be readily assessed, determining whether different oligodendrocyte sources influence myelin sheath formation. As well, the direct impact of both physical and molecular cues on oligodendrocytes can be determined in this defined system. This assay extends the capability of two-dimensional oligodendrocyte cultures, permitting post-differentiation analysis of myelinating oligodendrocytes, the number of sheaths formed by individual oligodendrocytes, as well as the lengths of myelin sheaths formed.
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Affiliation(s)
- Marie E Bechler
- MRC Centre for Regenerative Medicine, MS Society Edinburgh Centre for MS Research, The University of Edinburgh, Edinburgh, UK.
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19
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Sekizar S, Williams A. Ex Vivo Slice Cultures to Study Myelination, Demyelination, and Remyelination in Mouse Brain and Spinal Cord. Methods Mol Biol 2019; 1936:169-183. [PMID: 30820899 DOI: 10.1007/978-1-4939-9072-6_10] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In vitro culture systems have been invaluable in understanding the cell biology of oligodendrocytes; the monoculture of primary oligodendroglia has helped characterize different stages of oligodendrocyte maturation in the absence of neurons. However, oligodendrocyte monocultures do not model the interaction of oligodendrocytes with neurons where they form myelin wraps. To circumvent this problem, coculture systems were developed; oligodendrocytes and neurons are cultured together, facilitating the study of myelin wraps and the interaction between the two cell types. However, this coculture system also has limitations, as other cells are not present and it does not represent the three-dimensional multicellular structure seen in vivo. Some of these limitations are resolved by using ex vivo slice cultures to serve as a three-dimensional culture system that is more similar to in vivo and can be used to study myelination, demyelination, and remyelination, over extended periods of time. Slice cultures are economical compared to in vivo studies and live imaging using them is less challenging. The focus of this chapter is to describe how to culture brain and spinal cord slices of mice and use them to study myelination, demyelination, and remyelination.
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Affiliation(s)
- Sowmya Sekizar
- MRC Centre for Regenerative Medicine and MS Society Edinburgh Centre, Edinburgh bioQuarter, The University of Edinburgh, Edinburgh, UK
| | - Anna Williams
- MRC Centre for Regenerative Medicine and MS Society Edinburgh Centre, Edinburgh bioQuarter, The University of Edinburgh, Edinburgh, UK.
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20
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Abstract
Myelin sheaths are crucial for the survival and maintenance of the axons and the rapid propagation of the action potential. The glial cells involved are Schwann cells in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS). One oligodendrocyte may myelinate over 40 axons. In the CNS, myelin is composed of several layers of cytoplasmic membrane from oligodendrocytes stabilized by structural myelin-specific proteins such as proteolipid protein (PLP) and myelin basic protein (MBP). Those genes are expressed during myelination and then silenced. They can be re-expressed after demyelinating episodes, where they contribute to remyelination. Demyelination occurs after injuries of the CNS such as traumatic brain injury or during acute episodes of neurodegeneration observed in demyelinating and neurodegenerative diseases. Remyelination process is achieved by oligodendrocytes newly generated following the recruitment and differentiation of oligodendrocyte precursor cells (OPCs). Failure of remyelination process leads to irreversible axonal loss, functional impairment, and finally decreased cognitive performances. Several techniques have been described to study myelination and remyelination in culture systems. In this chapter, we explain how we can study myelin genes' expression in oligodendrocytes by real-time polymerase chain reaction (RT-PCR) using specific primers for plp and mbp. This technique can be crucial and prompt to determine the effect of specific chemicals (such as pesticides) on the myelination process in oligodendrocytes.
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Affiliation(s)
- Diala El Khoury
- Department of Biology Louaize Lebanon, NDU Natural and Applied Sciences, Notre Dame University, Zouk Mosbeh, Lebanon.
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21
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Ulc A, Zeug A, Bauch J, van Leeuwen S, Kuhlmann T, ffrench-Constant C, Ponimaskin E, Faissner A. The guanine nucleotide exchange factor Vav3 modulates oligodendrocyte precursor differentiation and supports remyelination in white matter lesions. Glia 2018; 67:376-392. [DOI: 10.1002/glia.23548] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 09/03/2018] [Accepted: 09/04/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Annika Ulc
- Department of Cell Morphology and Molecular Neurobiology; Ruhr-University Bochum; Germany
| | - Andre Zeug
- Cellular Neurophysiology, Centre for Physiology; Hannover Medical School; Hannover Germany
| | - Juliane Bauch
- Department of Cell Morphology and Molecular Neurobiology; Ruhr-University Bochum; Germany
| | - Simon van Leeuwen
- Department of Cell Morphology and Molecular Neurobiology; Ruhr-University Bochum; Germany
| | - Tanja Kuhlmann
- Institute of Neuropathology; University Hospital Münster; Germany
| | | | - Evgeni Ponimaskin
- Cellular Neurophysiology, Centre for Physiology; Hannover Medical School; Hannover Germany
| | - Andreas Faissner
- Department of Cell Morphology and Molecular Neurobiology; Ruhr-University Bochum; Germany
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22
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Treichel AJ, Hines JH. Development of an Embryonic Zebrafish Oligodendrocyte-Neuron Mixed Coculture System. Zebrafish 2018; 15:586-596. [PMID: 30300571 DOI: 10.1089/zeb.2018.1625] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
During vertebrate neural development, oligodendrocytes insulate nerve axons with myelin sheaths. Zebrafish (Danio rerio) has emerged as a useful model organism for studying oligodendrocyte development. However, the absence of an in vitro culture system necessitates in vivo manipulations and analyses, which, in some instances, limits the questions that can be addressed. To fill this gap we developed a mixed coculture system for embryonic zebrafish neurons and oligodendrocyte-lineage cells. Cultures harvested from embryos ≥30 hours postfertilization (hpf) yielded oligodendrocyte progenitor cells (OPCs) positive for olig2 and sox10 transgenic reporters. Cultured OPCs exhibited dynamic, exploratory membrane processes, and cell morphologies resembled those established in vivo. Cells harvested from advanced stage embryos possessed more arborized processes than those from early stage embryos. Advanced stage (>60 hpf) embryo culture produced differentiated, mbp+ oligodendrocytes. Genetically tractable neuron subtypes extended neurites when harvested from embryos ≥19 hpf. Coculture produced juxtaposed oligodendrocytes and neurons, demonstrating the practical usefulness of this technique for future studies examining axon-oligodendrocyte interactions under defined conditions. We expect that zebrafish oligodendrocyte culture will complement existing in vivo strengths and may facilitate future studies elucidating the mechanisms of oligodendrocyte specification, proliferation, differentiation, motility, and axon-oligodendrocyte interactions that shape adult myelination patterns.
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Affiliation(s)
| | - Jacob H Hines
- Department of Biology, Winona State University , Winona, Minnesota
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23
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Threshold-based segmentation of fluorescent and chromogenic images of microglia, astrocytes and oligodendrocytes in FIJI. J Neurosci Methods 2018; 295:87-103. [DOI: 10.1016/j.jneumeth.2017.12.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 12/01/2017] [Accepted: 12/04/2017] [Indexed: 01/31/2023]
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24
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Harboe M, Torvund-Jensen J, Kjaer-Sorensen K, Laursen LS. Ephrin-A1-EphA4 signaling negatively regulates myelination in the central nervous system. Glia 2018; 66:934-950. [PMID: 29350423 DOI: 10.1002/glia.23293] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 12/28/2017] [Accepted: 01/02/2018] [Indexed: 11/07/2022]
Abstract
During development of the central nervous system not all axons are myelinated, and axons may have distinct myelination patterns. Furthermore, the number of myelin sheaths formed by each oligodendrocyte is highly variable. However, our current knowledge about the axo-glia communication that regulates the formation of myelin sheaths spatially and temporally is limited. By using axon-mimicking microfibers and a zebrafish model system, we show that axonal ephrin-A1 inhibits myelination. Ephrin-A1 interacts with EphA4 to activate the ephexin1-RhoA-Rock-myosin 2 signaling cascade and causes inhibition of oligodendrocyte process extension. Both in myelinating co-cultures and in zebrafish larvae, activation of EphA4 decreases myelination, whereas myelination is increased by inhibition of EphA4 signaling at different levels of the pathway, or by receptor knockdown. Mechanistically, the enhanced myelination is a result of a higher number of myelin sheaths formed by each oligodendrocyte, not an increased number of mature cells. Thus, we have identified EphA4 and ephrin-A1 as novel negative regulators of myelination. Our data suggest that activation of an EphA4-RhoA pathway in oligodendrocytes by axonal ephrin-A1 inhibits stable axo-glia interaction required for generating a myelin sheath.
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Affiliation(s)
- Mette Harboe
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, Aarhus C, 8000, Denmark
| | - Julie Torvund-Jensen
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, Aarhus C, 8000, Denmark
| | - Kasper Kjaer-Sorensen
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, Aarhus C, 8000, Denmark
| | - Lisbeth S Laursen
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, Aarhus C, 8000, Denmark
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25
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Espinosa-Hoyos D, Jagielska A, Homan KA, Du H, Busbee T, Anderson DG, Fang NX, Lewis JA, Van Vliet KJ. Engineered 3D-printed artificial axons. Sci Rep 2018; 8:478. [PMID: 29323240 PMCID: PMC5765144 DOI: 10.1038/s41598-017-18744-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 12/16/2017] [Indexed: 12/02/2022] Open
Abstract
Myelination is critical for transduction of neuronal signals, neuron survival and normal function of the nervous system. Myelin disorders account for many debilitating neurological diseases such as multiple sclerosis and leukodystrophies. The lack of experimental models and tools to observe and manipulate this process in vitro has constrained progress in understanding and promoting myelination, and ultimately developing effective remyelination therapies. To address this problem, we developed synthetic mimics of neuronal axons, representing key geometric, mechanical, and surface chemistry components of biological axons. These artificial axons exhibit low mechanical stiffness approaching that of a human axon, over unsupported spans that facilitate engagement and wrapping by glial cells, to enable study of myelination in environments reflecting mechanical cues that neurons present in vivo. Our 3D printing approach provides the capacity to vary independently the complex features of the artificial axons that can reflect specific states of development, disease, or injury. Here, we demonstrate that oligodendrocytes' production and wrapping of myelin depend on artificial axon stiffness, diameter, and ligand coating. This biofidelic platform provides direct visualization and quantification of myelin formation and myelinating cells' response to both physical cues and pharmacological agents.
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Affiliation(s)
- Daniela Espinosa-Hoyos
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Biosystems & Micromechanics Interdisciplinary Research Group (BioSyM), Singapore-MIT Alliance in Research & Technology (SMART), Singapore, Singapore
| | - Anna Jagielska
- Biosystems & Micromechanics Interdisciplinary Research Group (BioSyM), Singapore-MIT Alliance in Research & Technology (SMART), Singapore, Singapore
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Kimberly A Homan
- Wyss Institute for Biologically Inspired Engineering, Cambridge, MA, 02138, USA
- School of Engineering and Applied Sciences, Harvard University, Harvard, MA, 02138, USA
| | - Huifeng Du
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Travis Busbee
- Wyss Institute for Biologically Inspired Engineering, Cambridge, MA, 02138, USA
- School of Engineering and Applied Sciences, Harvard University, Harvard, MA, 02138, USA
| | - Daniel G Anderson
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Harvard-MIT Division of Health Sciences & Technology, Cambridge, MA, 02139, USA
| | - Nicholas X Fang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Jennifer A Lewis
- Wyss Institute for Biologically Inspired Engineering, Cambridge, MA, 02138, USA
- School of Engineering and Applied Sciences, Harvard University, Harvard, MA, 02138, USA
| | - Krystyn J Van Vliet
- Biosystems & Micromechanics Interdisciplinary Research Group (BioSyM), Singapore-MIT Alliance in Research & Technology (SMART), Singapore, Singapore.
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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26
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Healy S, McMahon J, FitzGerald U. Seeing the wood for the trees: towards improved quantification of glial cells in central nervous system tissue. Neural Regen Res 2018; 13:1520-1523. [PMID: 30127105 PMCID: PMC6126125 DOI: 10.4103/1673-5374.235222] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The following mini-review attempts to guide researchers in the quantification of fluorescently-labelled proteins within cultured thick or chromogenically-stained proteins within thin sections of brain tissue. It follows from our examination of the utility of Fiji ImageJ thresholding and binarization algorithms. Describing how we identified the maximum intensity projection as the best of six tested for two dimensional (2D)-rendering of three-dimensional (3D) images derived from a series of z-stacked micrographs, the review summarises our comparison of 16 global and 9 local algorithms for their ability to accurately quantify the expression of astrocytic glial fibrillary acidic protein (GFAP), microglial ionized calcium binding adapter molecule 1 (IBA1) and oligodendrocyte lineage Olig2 within fixed cultured rat hippocampal brain slices. The application of these algorithms to chromogenically-stained GFAP and IBA1 within thin tissue sections, is also described. Fiji’s BioVoxxel plugin allowed categorisation of algorithms according to their sensitivity, specificity accuracy and relative quality. The Percentile algorithm was deemed best for quantifying levels of GFAP, the Li algorithm was best when quantifying IBA expression, while the Otsu algorithm was optimum for Olig2 staining, albeit with over-quantification of oligodendrocyte number when compared to a stereological approach. Also, GFAP and IBA expression in 3,3′-diaminobenzidine (DAB)/haematoxylin-stained cerebellar tissue was best quantified with Default, Isodata and Moments algorithms. The workflow presented in Figure 1 could help to improve the quality of research outcomes that are based on the quantification of protein with brain tissue.
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Affiliation(s)
- Sinéad Healy
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Jill McMahon
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Una FitzGerald
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
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27
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Plemel JR, Michaels NJ, Weishaupt N, Caprariello AV, Keough MB, Rogers JA, Yukseloglu A, Lim J, Patel VV, Rawji KS, Jensen SK, Teo W, Heyne B, Whitehead SN, Stys PK, Yong VW. Mechanisms of lysophosphatidylcholine-induced demyelination: A primary lipid disrupting myelinopathy. Glia 2017; 66:327-347. [PMID: 29068088 DOI: 10.1002/glia.23245] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 08/28/2017] [Accepted: 09/25/2017] [Indexed: 12/21/2022]
Abstract
For decades lysophosphatidylcholine (LPC, lysolecithin) has been used to induce demyelination, without a clear understanding of its mechanisms. LPC is an endogenous lysophospholipid so it may cause demyelination in certain diseases. We investigated whether known receptor systems, inflammation or nonspecific lipid disruption mediates LPC-demyelination in mice. We found that LPC nonspecifically disrupted myelin lipids. LPC integrated into cellular membranes and rapidly induced cell membrane permeability; in mice, LPC injury was phenocopied by other lipid disrupting agents. Interestingly, following its injection into white matter, LPC was cleared within 24 hr but by five days there was an elevation of endogenous LPC that was not associated with damage. This elevation of LPC in the absence of injury raises the possibility that the brain has mechanisms to buffer LPC. In support, LPC injury in culture was significantly ameliorated by albumin buffering. These results shed light on the mechanisms of LPC injury and homeostasis.
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Affiliation(s)
- Jason R Plemel
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Nathan J Michaels
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Nina Weishaupt
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, Western University, London, Ontario, N6A5C1, Canada
| | - Andrew V Caprariello
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Michael B Keough
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - James A Rogers
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Aran Yukseloglu
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Jaehyun Lim
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Vikas V Patel
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, Western University, London, Ontario, N6A5C1, Canada
| | - Khalil S Rawji
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Samuel K Jensen
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Wulin Teo
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Belinda Heyne
- Department of Chemistry, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - Shawn N Whitehead
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, Western University, London, Ontario, N6A5C1, Canada
| | - Peter K Stys
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
| | - V Wee Yong
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, T2N4N4, Canada
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28
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Choi JH, Cho HY, Choi JW. Microdevice Platform for In Vitro Nervous System and Its Disease Model. Bioengineering (Basel) 2017; 4:E77. [PMID: 28952555 PMCID: PMC5615323 DOI: 10.3390/bioengineering4030077] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 09/07/2017] [Accepted: 09/07/2017] [Indexed: 01/09/2023] Open
Abstract
The development of precise microdevices can be applied to the reconstruction of in vitro human microenvironmental systems with biomimetic physiological conditions that have highly tunable spatial and temporal features. Organ-on-a-chip can emulate human physiological functions, particularly at the organ level, as well as its specific roles in the body. Due to the complexity of the structure of the central nervous system and its intercellular interaction, there remains an urgent need for the development of human brain or nervous system models. Thus, various microdevice models have been proposed to mimic actual human brain physiology, which can be categorized as nervous system-on-a-chip. Nervous system-on-a-chip platforms can prove to be promising technologies, through the application of their biomimetic features to the etiology of neurodegenerative diseases. This article reviews the microdevices for nervous system-on-a-chip platform incorporated with neurobiology and microtechnology, including microfluidic designs that are biomimetic to the entire nervous system. The emulation of both neurodegenerative disorders and neural stem cell behavior patterns in micro-platforms is also provided, which can be used as a basis to construct nervous system-on-a-chip.
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Affiliation(s)
- Jin-Ha Choi
- Department of Chemical & Biomolecular Engineering, Sogang University, 35 Baekbeom-ro, Mapo-Gu, Seoul 04107, Korea.
| | - Hyeon-Yeol Cho
- Department of Chemical & Biomolecular Engineering, Sogang University, 35 Baekbeom-ro, Mapo-Gu, Seoul 04107, Korea.
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, NJ 08854, USA.
| | - Jeong-Woo Choi
- Department of Chemical & Biomolecular Engineering, Sogang University, 35 Baekbeom-ro, Mapo-Gu, Seoul 04107, Korea.
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29
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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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30
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Prasad A, Teh DBL, Blasiak A, Chai C, Wu Y, Gharibani PM, Yang IH, Phan TT, Lim KL, Yang H, Liu X, All AH. Static Magnetic Field Stimulation Enhances Oligodendrocyte Differentiation and Secretion of Neurotrophic Factors. Sci Rep 2017; 7:6743. [PMID: 28751716 PMCID: PMC5532210 DOI: 10.1038/s41598-017-06331-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 06/12/2017] [Indexed: 02/02/2023] Open
Abstract
The cellular-level effects of low/high frequency oscillating magnetic field on excitable cells such as neurons are well established. In contrast, the effects of a homogeneous, static magnetic field (SMF) on Central Nervous System (CNS) glial cells are less investigated. Here, we have developed an in vitro SMF stimulation set-up to investigate the genomic effects of SMF exposure on oligodendrocyte differentiation and neurotrophic factors secretion. Human oligodendrocytes precursor cells (OPCs) were stimulated with moderate intensity SMF (0.3 T) for a period of two weeks (two hours/day). The differential gene expression of cell activity marker (c-fos), early OPC (Olig1, Olig2. Sox10), and mature oligodendrocyte markers (CNP, MBP) were quantified. The enhanced myelination capacity of the SMF stimulated oligodendrocytes was validated in a dorsal root ganglion microfluidics chamber platform. Additionally, the effects of SMF on the gene expression and secretion of neurotrophic factors- BDNF and NT3 was quantified. We also report that SMF stimulation increases the intracellular calcium influx in OPCs as well as the gene expression of L-type channel subunits-CaV1.2 and CaV1.3. Our findings emphasize the ability of glial cells such as OPCs to positively respond to moderate intensity SMF stimulation by exhibiting enhanced differentiation, functionality as well as neurotrophic factor release.
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Affiliation(s)
- Ankshita Prasad
- Department of Biomedical Engineering, National University of Singapore, E4, 4 Engineering Drive 3, Singapore, 117583, Singapore
| | - Daniel B Loong Teh
- Singapore Institute of Neurotechnology (SINAPSE), National University of Singapore, 28 Medical Drive, 5-COR, Singapore, 117456, Singapore
| | - Agata Blasiak
- Singapore Institute of Neurotechnology (SINAPSE), National University of Singapore, 28 Medical Drive, 5-COR, Singapore, 117456, Singapore
| | - Chou Chai
- National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore
| | - Yang Wu
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
| | - Payam M Gharibani
- Department of Biomedical Engineering, John Hopkins School of Medicine, 701C Rutland Avenue 720, Baltimore, MD, 21205, USA
| | - In Hong Yang
- Singapore Institute of Neurotechnology (SINAPSE), National University of Singapore, 28 Medical Drive, 5-COR, Singapore, 117456, Singapore.,Department of Biomedical Engineering, John Hopkins School of Medicine, 701C Rutland Avenue 720, Baltimore, MD, 21205, USA
| | - Thang T Phan
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119228, Singapore
| | - Kah Leong Lim
- National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore.,Department of Physiology, 2 Medical Drive, MD9, National University of Singapore, 117593, Singapore, Singapore.,Duke-NUS Medical School. 8 College Road, 169857, Singapore, Singapore
| | - Hyunsoo Yang
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
| | - Xiaogang Liu
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore.
| | - Angelo H All
- Department of Biomedical Engineering, John Hopkins School of Medicine, 701C Rutland Avenue 720, Baltimore, MD, 21205, USA. .,Department of Neurology, John Hopkins School of Medicine, 701C Rutland Avenue 720, Baltimore, MD, 21205, USA.
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31
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Doussau F, Dupont JL, Neel D, Schneider A, Poulain B, Bossu JL. Organotypic cultures of cerebellar slices as a model to investigate demyelinating disorders. Expert Opin Drug Discov 2017; 12:1011-1022. [PMID: 28712329 DOI: 10.1080/17460441.2017.1356285] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
INTRODUCTION Demyelinating disorders, characterized by a chronic or episodic destruction of the myelin sheath, are a leading cause of neurological disability in young adults in western countries. Studying the complex mechanisms involved in axon myelination, demyelination and remyelination requires an experimental model preserving the neuronal networks and neuro-glial interactions. Organotypic cerebellar slice cultures appear to be the best alternative to in vivo experiments and the most commonly used model for investigating etiology or novel therapeutic strategies in multiple sclerosis. Areas covered: This review gives an overview of slice culture techniques and focuses on the use of organotypic cerebellar slice cultures on semi-permeable membranes for studying many aspects of axon myelination and cerebellar functions. Expert opinion: Cerebellar slice cultures are probably the easiest way to faithfully reproduce all stages of axon myelination/demyelination/remyelination in a three-dimensional neuronal network. However, in the cerebellum, neurological disability in multiple sclerosis also results from channelopathies which induce changes in Purkinje cell excitability. Cerebellar cultures offer easy access to electrophysiological approaches which are largely untapped and we believe that these cultures might be of great interest when studying changes in neuronal excitability, axonal conduction or synaptic properties that likely occur during multiple sclerosis.
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Affiliation(s)
- Frédéric Doussau
- a Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 , Université de Strasbourg , Strasbourg , France
| | - Jean-Luc Dupont
- a Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 , Université de Strasbourg , Strasbourg , France
| | - Dorine Neel
- a Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 , Université de Strasbourg , Strasbourg , France
| | - Aline Schneider
- a Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 , Université de Strasbourg , Strasbourg , France
| | - Bernard Poulain
- a Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 , Université de Strasbourg , Strasbourg , France
| | - Jean Louis Bossu
- a Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 , Université de Strasbourg , Strasbourg , France
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32
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Cole KLH, Early JJ, Lyons DA. Drug discovery for remyelination and treatment of MS. Glia 2017; 65:1565-1589. [PMID: 28618073 DOI: 10.1002/glia.23166] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/20/2017] [Accepted: 04/24/2017] [Indexed: 12/19/2022]
Abstract
Glia constitute the majority of the cells in our nervous system, yet there are currently no drugs that target glia for the treatment of disease. Given ongoing discoveries of the many roles of glia in numerous diseases of the nervous system, this is likely to change in years to come. Here we focus on the possibility that targeting the oligodendrocyte lineage to promote regeneration of myelin (remyelination) represents a therapeutic strategy for the treatment of the demyelinating disease multiple sclerosis, MS. We discuss how hypothesis driven studies have identified multiple targets and pathways that can be manipulated to promote remyelination in vivo, and how this work has led to the first ever remyelination clinical trials. We also highlight how recent chemical discovery screens have identified a host of small molecule compounds that promote oligodendrocyte differentiation in vitro. Some of these compounds have also been shown to promote myelin regeneration in vivo, with one already being trialled in humans. Promoting oligodendrocyte differentiation and remyelination represents just one potential strategy for the treatment of MS. The pathology of MS is complex, and its complete amelioration may require targeting multiple biological processes in parallel. Therefore, we present an overview of new technologies and models for phenotypic analyses and screening that can be exploited to study complex cell-cell interactions in in vitro and in vivo systems. Such technological platforms will provide insight into fundamental mechanisms and increase capacities for drug-discovery of relevance to glia and currently intractable disorders of the CNS.
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Affiliation(s)
- Katy L H Cole
- Centre for Neuroregeneration, MS Society Centre for Translational Research, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, United Kingdom
| | - Jason J Early
- Centre for Neuroregeneration, MS Society Centre for Translational Research, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, United Kingdom
| | - David A Lyons
- Centre for Neuroregeneration, MS Society Centre for Translational Research, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, United Kingdom
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33
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Zhang ZH, Zhao WQ, Ma FF, Zhang H, Xu XH. Rab10 Disruption Results in Delayed OPC Maturation. Cell Mol Neurobiol 2017; 37:1303-1310. [DOI: 10.1007/s10571-017-0465-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 01/16/2017] [Indexed: 12/14/2022]
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34
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Ramamurthy P, White JB, Yull Park J, Hume RI, Ebisu F, Mendez F, Takayama S, Barald KF. Concomitant differentiation of a population of mouse embryonic stem cells into neuron-like cells and schwann cell-like cells in a slow-flow microfluidic device. Dev Dyn 2017; 246:7-27. [PMID: 27761977 PMCID: PMC5159187 DOI: 10.1002/dvdy.24466] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 09/16/2016] [Accepted: 09/30/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND To send meaningful information to the brain, an inner ear cochlear implant (CI) must become closely coupled to as large and healthy a population of remaining spiral ganglion neurons (SGN) as possible. Inner ear gangliogenesis depends on macrophage migration inhibitory factor (MIF), a directionally attractant neurotrophic cytokine made by both Schwann and supporting cells (Bank et al., 2012). MIF-induced mouse embryonic stem cell (mESC)-derived "neurons" could potentially substitute for lost or damaged SGN. mESC-derived "Schwann cells" produce MIF, as do all Schwann cells (Huang et al., a; Roth et al., 2007; Roth et al., 2008) and could attract SGN to a "cell-coated" implant. RESULTS Neuron- and Schwann cell-like cells were produced from a common population of mESCs in an ultra-slow-flow microfluidic device. As the populations interacted, "neurons" grew over the "Schwann cell" lawn, and early events in myelination were documented. Blocking MIF on the Schwann cell side greatly reduced directional neurite outgrowth. MIF-expressing "Schwann cells" were used to coat a CI: Mouse SGN and MIF-induced "neurons" grew directionally to the CI and to a wild-type but not MIF-knockout organ of Corti explant. CONCLUSIONS Two novel stem cell-based approaches for treating the problem of sensorineural hearing loss are described. Developmental Dynamics 246:7-27, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Poornapriya Ramamurthy
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Joshua B White
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan
| | - Joong Yull Park
- School of Mechanical Engineering, College of Engineering, Chung-Ang University, Seoul, Republic of Korea
| | - Richard I Hume
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan
| | - Fumi Ebisu
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Flor Mendez
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Shuichi Takayama
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan
| | - Kate F Barald
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan
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Rab27b is Involved in Lysosomal Exocytosis and Proteolipid Protein Trafficking in Oligodendrocytes. Neurosci Bull 2016; 32:331-40. [PMID: 27325508 DOI: 10.1007/s12264-016-0045-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/31/2016] [Indexed: 12/14/2022] Open
Abstract
Myelination by oligodendrocytes in the central nervous system requires coordinated exocytosis and endocytosis of the major myelin protein, proteolipid protein (PLP). Here, we demonstrated that a small GTPase, Rab27b, is involved in PLP trafficking in oligodendrocytes. We showed that PLP co-localized with Rab27b in late endosomes/lysosomes in oligodendrocytes. Short hairpin-mediated knockdown of Rab27b not only reduced lysosomal exocytosis but also greatly diminished the surface expression of PLP in oligodendrocytes. In addition, knockdown of Rab27b reduced the myelin-like membranes induced by co-culture of oligodendrocytes and neurons. Our data suggest that Rab27b is involved in myelin biogenesis by regulating PLP transport from late endosomes/lysosomes to the cell membrane in oligodendrocytes.
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Abstract
In the nervous system, axons transmit information in the form of electrical impulses over long distances. The speed of impulse conduction is enhanced by myelin, a lipid-rich membrane that wraps around axons. Myelin also is required for the long-term health of axons by providing metabolic support. Accordingly, myelin deficiencies are implicated in a wide range of neurodevelopmental and neuropsychiatric disorders, intellectual disabilities, and neurodegenerative conditions. Central nervous system myelin is formed by glial cells called oligodendrocytes. During development, oligodendrocyte precursor cells migrate from their origins to their target axons, extend long membrane processes that wrap axons, and produce the proteins and lipids that provide myelin membrane with its unique characteristics. Myelination is a dynamic process that involves intricate interactions between multiple cell types. Therefore, an in vivo myelination model, such as the zebrafish, which allows for live observation of cell dynamics and cell-to-cell interactions, is well suited for investigating oligodendrocyte development. Zebrafish offer several advantages to investigating myelination, including the use of transgenic reporter lines, live imaging, forward genetic screens, chemical screens, and reverse genetic approaches. This chapter will describe how these tools and approaches have provided new insights into the regulatory mechanisms that guide myelination.
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Affiliation(s)
- E S Mathews
- University of Colorado School of Medicine, Aurora, CO, United States
| | - B Appel
- University of Colorado School of Medicine, Aurora, CO, United States
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de la Fuente AG, Errea O, van Wijngaarden P, Gonzalez GA, Kerninon C, Jarjour AA, Lewis HJ, Jones CA, Nait-Oumesmar B, Zhao C, Huang JK, ffrench-Constant C, Franklin RJM. Vitamin D receptor-retinoid X receptor heterodimer signaling regulates oligodendrocyte progenitor cell differentiation. J Cell Biol 2015; 211:975-85. [PMID: 26644513 PMCID: PMC4674280 DOI: 10.1083/jcb.201505119] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 10/27/2015] [Indexed: 02/03/2023] Open
Abstract
The mechanisms regulating differentiation of oligodendrocyte (OLG) progenitor cells (OPCs) into mature OLGs are key to understanding myelination and remyelination. Signaling via the retinoid X receptor γ (RXR-γ) has been shown to be a positive regulator of OPC differentiation. However, the nuclear receptor (NR) binding partner of RXR-γ has not been established. In this study we show that RXR-γ binds to several NRs in OPCs and OLGs, one of which is vitamin D receptor (VDR). Using pharmacological and knockdown approaches we show that RXR-VDR signaling induces OPC differentiation and that VDR agonist vitamin D enhances OPC differentiation. We also show expression of VDR in OLG lineage cells in multiple sclerosis. Our data reveal a role for vitamin D in the regenerative component of demyelinating disease and identify a new target for remyelination medicines.
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Affiliation(s)
- Alerie Guzman de la Fuente
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge CB2 0AH, England, UK
| | - Oihana Errea
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge CB2 0AH, England, UK
| | - Peter van Wijngaarden
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge CB2 0AH, England, UK Centre for Eye Research, University of Melbourne, Royal Victorian Eye and Ear Hospital, Victoria 3002, Australia
| | - Ginez A Gonzalez
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge CB2 0AH, England, UK
| | - Christophe Kerninon
- Institut du Cerveau et de la Moelle Epinière, Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche 1127, 75651 Paris, France
| | - Andrew A Jarjour
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, Scotland, UK
| | | | | | - Brahim Nait-Oumesmar
- Institut du Cerveau et de la Moelle Epinière, Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche 1127, 75651 Paris, France
| | - Chao Zhao
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge CB2 0AH, England, UK
| | - Jeffrey K Huang
- Department of Biology, Georgetown University, Washington, DC 20057
| | - Charles ffrench-Constant
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, Scotland, UK
| | - Robin J M Franklin
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge CB2 0AH, England, UK
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Wei W, Wang Y, Dong J, Wang Y, Min H, Song B, Shan Z, Teng W, Xi Q, Chen J. Hypothyroxinemia induced by maternal mild iodine deficiency impairs hippocampal myelinated growth in lactational rats. ENVIRONMENTAL TOXICOLOGY 2015; 30:1264-1274. [PMID: 24753110 DOI: 10.1002/tox.21997] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 04/01/2014] [Accepted: 04/04/2014] [Indexed: 06/03/2023]
Abstract
Hypothyroxinemia induced by maternal mild iodine deficiency causes neurological deficits and impairments of brain function in offspring. Hypothyroxinemia is prevalent in developing and developed countries alike. However, the mechanism underlying these deficits remains less well known. Given that the myelin plays an important role in learning and memory function, we hypothesize that hippocampal myelinated growth may be impaired in rat offspring exposed to hypothyroxinemia induced by maternal mild iodine deficiency. To test this hypothesis, the female Wistar rats were used and four experimental groups were prepared: (1) control; (2) maternal mild iodine deficiency diet inducing hypothyroxinemia; (3) hypothyroidism induced by maternal severe iodine deficiency diet; (4) hypothyroidism induced by maternal methimazole water. The rats were fed the diet from 3 months before pregnancy to the end of lactation. Our results showed that the physiological changes occuring in the hippocampal myelin were altered in the mild iodine deficiency group as indicated by the results of immunofluorescence of myelin basic proteins on postnatal day 14 and postnatal day 21. Moreover, hypothyroxinemia reduced the expressions of oligodendrocyte lineage transcription factor 2 and myelin-related proteins in the treatments on postnatal day 14 and postnatal day 21. Our data suggested that hypothyroxinemia induced by maternal mild iodine deficiency may impair myelinated growth of the offspring.
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Affiliation(s)
- Wei Wei
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Yi Wang
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Jing Dong
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Yuan Wang
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
| | - Hui Min
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
| | - Binbin Song
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
| | - Zhongyan Shan
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Weiping Teng
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
| | - Qi Xi
- Department of Physiology, the University of Tennessee Health Science Center, Memphis, Tennessee, 38163, USA
| | - Jie Chen
- Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, People's Republic of China
- Department of Endocrinology and Metabolism and Liaoning Provincial Key Laboratory of Endocrine Diseases, the First Hospital of China Medical University, Shenyang, People's Republic of China
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Rassul SM, Neely RK, Fulton D. Live-imaging in the CNS: New insights on oligodendrocytes, myelination, and their responses to inflammation. Neuropharmacology 2015; 110:594-604. [PMID: 26407765 DOI: 10.1016/j.neuropharm.2015.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 07/31/2015] [Accepted: 09/08/2015] [Indexed: 11/18/2022]
Abstract
The formation and repair of myelin involves alterations in the molecular and physical properties of oligodendrocytes, and highly coordinated interactions with their target axons. Characterising the nature and timing of these events at the molecular and cellular levels illuminates the fundamental events underlying myelin formation, and provides opportunities for the development of therapies to replace myelin lost through traumatic injury and inflammation. The dynamic nature of these events requires that live-imaging methods be used to capture this information accurately and completely. Developments in imaging technologies, and model systems suitable for their application to myelination, have advanced the study of myelin formation, injury and repair. Similarly, new techniques for single molecule imaging, and novel imaging probes, are providing opportunities to resolve the dynamics of myelin proteins during myelination. Here, we explore these developments in the context of myelin formation and injury, identify unmet needs within the field where progress can be advanced through live-imaging approaches, identify technical challenges that are limiting this progress, and highlight practical applications for these approaches that could lead to therapies for the protection of oligodendrocytes and myelin from injury, and restore myelin lost through injury and disease. This article is part of the Special Issue entitled 'Oligodendrocytes in Health and Disease'.
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Affiliation(s)
- Sayed Muhammed Rassul
- Physical Sciences of Imaging in the Biomedical Sciences Training Programme, University of Birmingham, Birmingham, UK
| | - Robert K Neely
- School of Chemistry, University of Birmingham, Birmingham, UK
| | - Daniel Fulton
- Neurotrauma Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
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40
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Preston MA, Macklin WB. Zebrafish as a model to investigate CNS myelination. Glia 2014; 63:177-93. [PMID: 25263121 DOI: 10.1002/glia.22755] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 09/12/2014] [Indexed: 12/18/2022]
Abstract
Myelin plays a critical role in proper neuronal function by providing trophic and metabolic support to axons and facilitating energy-efficient saltatory conduction. Myelination is influenced by numerous molecules including growth factors, hormones, transmembrane receptors and extracellular molecules, which activate signaling cascades that drive cellular maturation. Key signaling molecules and downstream signaling cascades controlling myelination have been identified in cell culture systems. However, in vitro systems are not able to faithfully replicate the complex in vivo signaling environment that occurs during development or following injury. Currently, it remains time-consuming and expensive to investigate myelination in vivo in rodents, the most widely used model for studying mammalian myelination. As such, there is a need for alternative in vivo myelination models, particularly ones that can test molecular mechanisms without removing oligodendrocyte lineage cells from their native signaling environment or disrupting intercellular interactions with other cell types present during myelination. Here, we review the ever-increasing role of zebrafish in studies uncovering novel mechanisms controlling vertebrate myelination. These innovative studies range from observations of the behavior of single cells during in vivo myelination as well as mutagenesis- and pharmacology-based screens in whole animals. Additionally, we discuss recent efforts to develop novel models of demyelination and oligodendrocyte cell death in adult zebrafish for the study of cellular behavior in real time during repair and regeneration of damaged nervous systems.
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Affiliation(s)
- Marnie A Preston
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado
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41
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El Waly B, Macchi M, Cayre M, Durbec P. Oligodendrogenesis in the normal and pathological central nervous system. Front Neurosci 2014; 8:145. [PMID: 24971048 PMCID: PMC4054666 DOI: 10.3389/fnins.2014.00145] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 05/23/2014] [Indexed: 12/26/2022] Open
Abstract
Oligodendrocytes (OLGs) are generated late in development and myelination is thus a tardive event in the brain developmental process. It is however maintained whole life long at lower rate, and myelin sheath is crucial for proper signal transmission and neuronal survival. Unfortunately, OLGs present a high susceptibility to oxidative stress, thus demyelination often takes place secondary to diverse brain lesions or pathologies. OLGs can also be the target of immune attacks, leading to primary demyelination lesions. Following oligodendrocytic death, spontaneous remyelination may occur to a certain extent. In this review, we will mainly focus on the adult brain and on the two main sources of progenitor cells that contribute to oligodendrogenesis: parenchymal oligodendrocyte precursor cells (OPCs) and subventricular zone (SVZ)-derived progenitors. We will shortly come back on the main steps of oligodendrogenesis in the postnatal and adult brain, and summarize the key factors involved in the determination of oligodendrocytic fate. We will then shed light on the main causes of demyelination in the adult brain and present the animal models that have been developed to get insight on the demyelination/remyelination process. Finally, we will synthetize the results of studies searching for factors able to modulate spontaneous myelin repair.
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Affiliation(s)
- Bilal El Waly
- CNRS, Institut de Biologie du Développement de Marseille UMR 7288, Aix Marseille Université Marseille, France
| | - Magali Macchi
- CNRS, Institut de Biologie du Développement de Marseille UMR 7288, Aix Marseille Université Marseille, France
| | - Myriam Cayre
- CNRS, Institut de Biologie du Développement de Marseille UMR 7288, Aix Marseille Université Marseille, France
| | - Pascale Durbec
- CNRS, Institut de Biologie du Développement de Marseille UMR 7288, Aix Marseille Université Marseille, France
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42
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Goudriaan A, Camargo N, Carney KE, Oliet SHR, Smit AB, Verheijen MHG. Novel cell separation method for molecular analysis of neuron-astrocyte co-cultures. Front Cell Neurosci 2014; 8:12. [PMID: 24523672 PMCID: PMC3906515 DOI: 10.3389/fncel.2014.00012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 01/08/2014] [Indexed: 11/15/2022] Open
Abstract
Over the last decade, the importance of astrocyte-neuron communication in neuronal development and synaptic plasticity has become increasingly clear. Since neuron-astrocyte interactions represent highly dynamic and reciprocal processes, we hypothesized that many astrocyte genes may be regulated as a consequence of their interactions with maturing neurons. In order to identify such neuron-responsive astrocyte genes in vitro, we sought to establish an expedited technique for separation of neurons from co-cultured astrocytes. Our newly established method makes use of cold jet, which exploits different adhesion characteristics of subpopulations of cells (Jirsova etal., 1997), and is rapid, performed under ice-cold conditions and avoids protease-mediated isolation of astrocytes or time-consuming centrifugation, yielding intact astrocyte mRNA with approximately 90% of neuronal RNA removed. Using this purification method, we executed genome-wide profiling in which RNA derived from astrocyte-only cultures was compared with astrocyte RNA derived from differentiating neuron-astrocyte co-cultures. Data analysis determined that many astrocytic mRNAs and biological processes are regulated by neuronal interaction. Our results validate the cold jet as an efficient method to separate astrocytes from neurons in co-culture, and reveals that neurons induce robust gene-expression changes in co-cultured astrocytes.
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Affiliation(s)
- Andrea Goudriaan
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Amsterdam Amsterdam, Netherlands
| | - Nutabi Camargo
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Amsterdam Amsterdam, Netherlands
| | - Karen E Carney
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Amsterdam Amsterdam, Netherlands ; INSERM U862, Neurocentre Magendie Bordeaux, France ; Université de Bordeaux Bordeaux, France
| | - Stéphane H R Oliet
- INSERM U862, Neurocentre Magendie Bordeaux, France ; Université de Bordeaux Bordeaux, France
| | - August B Smit
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Amsterdam Amsterdam, Netherlands
| | - Mark H G Verheijen
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Amsterdam Amsterdam, Netherlands
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Kolaric KV, Thomson G, Edgar JM, Brown AM. Focal axonal swellings and associated ultrastructural changes attenuate conduction velocity in central nervous system axons: a computer modeling study. Physiol Rep 2013; 1:e00059. [PMID: 24303138 PMCID: PMC3835014 DOI: 10.1002/phy2.59] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 07/22/2013] [Accepted: 07/25/2013] [Indexed: 12/11/2022] Open
Abstract
The constancy of action potential conduction in the central nervous system (CNS) relies on uniform axon diameter coupled with fidelity of the overlying myelin providing high-resistance, low capacitance insulation. Whereas the effects of demyelination on conduction have been extensively studied/modeled, equivalent studies on the repercussions for conduction of axon swelling, a common early pathological feature of (potentially reversible) axonal injury, are lacking. The recent description of experimentally acquired morphological and electrical properties of small CNS axons and oligodendrocytes prompted us to incorporate these data into a computer model, with the aim of simulating the effects of focal axon swelling on action potential conduction. A single swelling on an otherwise intact axon, as occurs in optic nerve axons of Cnp1 null mice caused a small decrease in conduction velocity. The presence of single swellings on multiple contiguous internodal regions (INR), as likely occurs in advanced disease, caused qualitatively similar results, except the dimensions of the swellings required to produce equivalent attenuation of conduction were significantly decreased. Our simulations of the consequences of metabolic insult to axons, namely, the appearance of multiple swollen regions, accompanied by perturbation of overlying myelin and increased axolemmal permeability, contained within a single INR, revealed that conduction block occurred when the dimensions of the simulated swellings were within the limits of those measured experimentally, suggesting that multiple swellings on a single axon could contribute to axonal dysfunction, and that increased axolemmal permeability is the decisive factor that promotes conduction block.
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Affiliation(s)
- Katarina V Kolaric
- School of Biomedical Sciences, Queens Medical Centre, University of Nottingham Nottingham, NG7 2UH, U.K
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44
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Mathew A, Pakan JMP, Collin EC, Wang W, McDermott KW, Fitzgerald U, Reynolds R, Pandit AS. An ex-vivo multiple sclerosis model of inflammatory demyelination using hyperbranched polymer. Biomaterials 2013; 34:5872-82. [PMID: 23660252 DOI: 10.1016/j.biomaterials.2013.04.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 04/04/2013] [Indexed: 12/16/2022]
Abstract
Multiple sclerosis (MS) is characterized by the presence of inflammatory demyelinating foci throughout the brain and spinal cord, accompanied by axonal and neuronal damage. Although inflammatory processes are thought to underlie the pathological changes, the individual mediators of this damage are unclear. In order to study the role of pro-inflammatory cytokines in demyelination in the central nervous system, we have utilized a hyperbranched poly(2-dimethyl-aminoethylmethacrylate) based non-viral gene transfection system to establish an inflammatory demyelinating model of MS in an ex-vivo environment. The synthesized non-viral gene transfection system was optimized for efficient transfection with minimal cytotoxicity. Organotypic brain slices were then successfully transfected with the TNF or IFNγ genes. TNF and IFNγ expression and release in cerebellar slices via non-viral gene delivery approach resulted in inflammation mediated myelin loss, thus making it a promising ex-vivo approach for studying the underlying mechanisms of demyelination in myelin-related diseases such as MS.
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Affiliation(s)
- Asha Mathew
- Network of Excellence for Functional Biomaterials, National University of Ireland, Galway, Ireland
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45
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Harauz G, Boggs JM. Myelin management by the 18.5-kDa and 21.5-kDa classic myelin basic protein isoforms. J Neurochem 2013; 125:334-61. [PMID: 23398367 DOI: 10.1111/jnc.12195] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 02/05/2013] [Accepted: 02/05/2013] [Indexed: 12/15/2022]
Abstract
The classic myelin basic protein (MBP) splice isoforms range in nominal molecular mass from 14 to 21.5 kDa, and arise from the gene in the oligodendrocyte lineage (Golli) in maturing oligodendrocytes. The 18.5-kDa isoform that predominates in adult myelin adheres the cytosolic surfaces of oligodendrocyte membranes together, and forms a two-dimensional molecular sieve restricting protein diffusion into compact myelin. However, this protein has additional roles including cytoskeletal assembly and membrane extension, binding to SH3-domains, participation in Fyn-mediated signaling pathways, sequestration of phosphoinositides, and maintenance of calcium homeostasis. Of the diverse post-translational modifications of this isoform, phosphorylation is the most dynamic, and modulates 18.5-kDa MBP's protein-membrane and protein-protein interactions, indicative of a rich repertoire of functions. In developing and mature myelin, phosphorylation can result in microdomain or even nuclear targeting of the protein, supporting the conclusion that 18.5-kDa MBP has significant roles beyond membrane adhesion. The full-length, early-developmental 21.5-kDa splice isoform is predominantly karyophilic due to a non-traditional P-Y nuclear localization signal, with effects such as promotion of oligodendrocyte proliferation. We discuss in vitro and recent in vivo evidence for multifunctionality of these classic basic proteins of myelin, and argue for a systematic evaluation of the temporal and spatial distributions of these protein isoforms, and their modified variants, during oligodendrocyte differentiation.
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Affiliation(s)
- George Harauz
- Department of Molecular and Cellular Biology, Biophysics Interdepartmental Group and Collaborative Program in Neuroscience, University of Guelph, Guelph, Ontario, Canada.
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Park YM, Lee WT, Bokara KK, Seo SK, Park SH, Kim JH, Yenari MA, Park KA, Lee JE. The multifaceted effects of agmatine on functional recovery after spinal cord injury through Modulations of BMP-2/4/7 expressions in neurons and glial cells. PLoS One 2013; 8:e53911. [PMID: 23349763 PMCID: PMC3549976 DOI: 10.1371/journal.pone.0053911] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 12/04/2012] [Indexed: 11/29/2022] Open
Abstract
Presently, few treatments for spinal cord injury (SCI) are available and none have facilitated neural regeneration and/or significant functional improvement. Agmatine (Agm), a guanidinium compound formed from decarboxylation of L-arginine by arginine decarboxylase, is a neurotransmitter/neuromodulator and been reported to exert neuroprotective effects in central nervous system injury models including SCI. The purpose of this study was to demonstrate the multifaceted effects of Agm on functional recovery and remyelinating events following SCI. Compression SCI in mice was produced by placing a 15 g/mm2 weight for 1 min at thoracic vertebra (Th) 9 segment. Mice that received an intraperitoneal (i.p.) injection of Agm (100 mg/kg/day) within 1 hour after SCI until 35 days showed improvement in locomotor recovery and bladder function. Emphasis was made on the analysis of remyelination events, neuronal cell preservation and ablation of glial scar area following SCI. Agm treatment significantly inhibited the demyelination events, neuronal loss and glial scar around the lesion site. In light of recent findings that expressions of bone morphogenetic proteins (BMPs) are modulated in the neuronal and glial cell population after SCI, we hypothesized whether Agm could modulate BMP- 2/4/7 expressions in neurons, astrocytes, oligodendrocytes and play key role in promoting the neuronal and glial cell survival in the injured spinal cord. The results from computer assisted stereological toolbox analysis (CAST) demonstrate that Agm treatment dramatically increased BMP- 2/7 expressions in neurons and oligodendrocytes. On the other hand, BMP- 4 expressions were significantly decreased in astrocytes and oligodendrocytes around the lesion site. Together, our results reveal that Agm treatment improved neurological and histological outcomes, induced oligodendrogenesis, protected neurons, and decreased glial scar formation through modulating the BMP- 2/4/7 expressions following SCI.
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Affiliation(s)
- Yu Mi Park
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
- BK 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Won Taek Lee
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Kiran Kumar Bokara
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Su Kyoung Seo
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
- BK 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Seung Hwa Park
- Department of Anatomy, Konkuk University College of Medicine, Seoul, Republic of Korea
| | - Jae Hwan Kim
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Midori A. Yenari
- Department of Neurology, University of California San Francisco and Veterans Affairs Medical Center, San Francisco, California, United States of America
| | - Kyung Ah Park
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jong Eun Lee
- Department of Anatomy, Yonsei University College of Medicine, Seoul, Republic of Korea
- BK 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
- * E-mail:
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47
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Live imaging of targeted cell ablation in Xenopus: a new model to study demyelination and repair. J Neurosci 2012; 32:12885-95. [PMID: 22973012 DOI: 10.1523/jneurosci.2252-12.2012] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Live imaging studies of the processes of demyelination and remyelination have so far been technically limited in mammals. We have thus generated a Xenopus laevis transgenic line allowing live imaging and conditional ablation of myelinating oligodendrocytes throughout the CNS. In these transgenic pMBP-eGFP-NTR tadpoles the myelin basic protein (MBP) regulatory sequences, specific to mature oligodendrocytes, are used to drive expression of an eGFP (enhanced green fluorescent protein) reporter fused to the Escherichia coli nitroreductase (NTR) selection enzyme. This enzyme converts the innocuous prodrug metronidazole (MTZ) to a cytotoxin. Using two-photon imaging in vivo, we show that pMBP-eGFP-NTR tadpoles display a graded oligodendrocyte ablation in response to MTZ, which depends on the exposure time to MTZ. MTZ-induced cell death was restricted to oligodendrocytes, without detectable axonal damage. After cessation of MTZ treatment, remyelination proceeded spontaneously, but was strongly accelerated by retinoic acid. Altogether, these features establish the Xenopus pMBP-eGFP-NTR line as a novel in vivo model for the study of demyelination/remyelination processes and for large-scale screens of therapeutic agents promoting myelin repair.
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Ravikumar M, Jain S, Miller RH, Capadona JR, Selkirk SM. An organotypic spinal cord slice culture model to quantify neurodegeneration. J Neurosci Methods 2012; 211:280-8. [PMID: 22975474 DOI: 10.1016/j.jneumeth.2012.09.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 08/19/2012] [Accepted: 09/04/2012] [Indexed: 02/07/2023]
Abstract
Activated microglia cells have been implicated in the neurodegenerative process of Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and multiple sclerosis; however, the precise roles of microglia in disease progression are unclear. Despite these diseases having been described for more than a century, current FDA approved therapeutics are symptomatic in nature with little evidence to supporting a neuroprotective effect. Furthermore, identifying novel therapeutics remains challenging due to undetermined etiology, a variable disease course, and the paucity of validated targets. Here, we describe the use of a novel ex vivo spinal cord culture system that offers the ability to screen potential neuroprotective agents, while maintaining the complexity of the in vivo environment. To this end, we treated spinal cord slice cultures with lipopolysaccharide and quantified neuron viability in culture using measurements of axon length and FluoroJadeC intensity. To simulate a microglia-mediated response to cellular debris, antigens, or implanted materials/devices, we supplemented the culture media with increasing densities of microspheres, facilitating microglia-mediated phagocytosis of the particles, which demonstrated a direct correlation between the phagocytic activities of microglia and neuronal health. To validate our model's capacity to accurately depict neuroprotection, cultures were treated with resveratrol, which demonstrated enhanced neuronal health. Our results successfully demonstrate the use of this model to reproducibly quantify the extent of neurodegeneration through the measurement of axon length and FluoroJadeC intensity, and we suggest this model will allow for accurate, high-throughput screening, which could result in expedited success in translational efficacy of therapeutic agents to clinical trials.
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Affiliation(s)
- Madhumitha Ravikumar
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 Martin Luther King Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA
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Murphy RP, Murphy KJ, Pickering M. The development of myelin repair agents for treatment of multiple sclerosis: progress and challenges. Bioengineered 2012; 4:140-6. [PMID: 23147071 DOI: 10.4161/bioe.22835] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Multiple Sclerosis (MS) is an inflammatory demyelinating disorder which affects the central nervous system. Multiple sclerosis treatment has traditionally focused on preventing inflammatory damage to the myelin sheath. Indeed, all currently available disease modifying agents are immunomodulators. However, the limitations of this approach are becoming increasingly clear, leading to the exploration of other potential therapeutic strategies. In particular, targeting the endogenous remyelination system to promote replacement of the lost myelin sheath has shown much promise. As our understanding of remyelination biology advances, the realization of a remyelinating therapeutic comes closer to fruition. In our review, we aim to summarize the limitations of the current immune focused treatment strategy and discuss the potential of remyelination as a new treatment method. Finally, we aim to highlight the challenges in the identification and development of such therapeutics.
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Affiliation(s)
- Robert P Murphy
- Neurotherapeutics Research Group, UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
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Abstract
Astrocytes are the most abundant cell type in the adult central nervous system (CNS), and their functional diversity in response to injury is now being appreciated. Astrocytes have long been considered the main player in the inhibition of CNS repair via the formation of the gliotic scar, but now it is accepted that astrocyte can play an important role in CNS repair and remyelination. Interest in the relationship between astrocytes and myelination focused initially on attempts to understand how the development of plaques of astroglial scar tissue in multiple sclerosis was related to the failure of these lesions to remyelinate. It is now considered that this is an end stage pathological response to injury, and that normally astrocytes play important roles in supporting the development and maintenance of CNS myelin. This review will focus on how this new understanding may be exploited to develop new strategies to enhance remyelination in multiple sclerosis and other diseases.
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Affiliation(s)
- Susan C Barnett
- Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, UK.
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