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O'Donnell BL, Penuela S. Skin in the game: pannexin channels in healthy and cancerous skin. Biochem J 2023; 480:1929-1949. [PMID: 38038973 DOI: 10.1042/bcj20230176] [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: 09/29/2023] [Revised: 11/15/2023] [Accepted: 11/20/2023] [Indexed: 12/02/2023]
Abstract
The skin is a highly organized tissue composed of multiple layers and cell types that require coordinated cell to cell communication to maintain tissue homeostasis. In skin cancer, this organized structure and communication is disrupted, prompting the malignant transformation of healthy cells into melanoma, basal cell carcinoma or squamous cell carcinoma tumours. One such family of channel proteins critical for cellular communication is pannexins (PANX1, PANX2, PANX3), all of which are present in the skin. These heptameric single-membrane channels act as conduits for small molecules and ions like ATP and Ca2+ but have also been shown to have channel-independent functions through their interacting partners or action in signalling pathways. Pannexins have diverse roles in the skin such as in skin development, aging, barrier function, keratinocyte differentiation, inflammation, and wound healing, which were discovered through work with pannexin knockout mice, organotypic epidermis models, primary cells, and immortalized cell lines. In the context of cutaneous cancer, PANX1 is present at high levels in melanoma tumours and functions in melanoma carcinogenesis, and both PANX1 and PANX3 expression is altered in non-melanoma skin cancer. PANX2 has thus far not been implicated in any skin cancer. This review will discuss pannexin isoforms, structure, trafficking, post-translational modifications, interactome, and channel activity. We will also outline the expression, localization, and function of pannexin channels within the diverse cell types of the epidermis, dermis, hypodermis, and adnexal structures of the skin, and how these properties are exploited or abrogated in instances of skin cancer.
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Affiliation(s)
- Brooke L O'Donnell
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada N6A 5C1
| | - Silvia Penuela
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada N6A 5C1
- Department of Oncology, Division of Experimental Oncology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada N6A 5C1
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2
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Vinken M. Toxic talk: pannexin1 channel communication as an emerging mechanism of toxicity. Toxicology 2022; 478:153295. [PMID: 35998787 DOI: 10.1016/j.tox.2022.153295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 10/15/2022]
Abstract
Pannexin1 channels facilitate the extracellular release of a number of messengers, including adenosine triphosphate. Although fulfilling some physiological functions, pannexin1 channel communication has to date been primarily studied in the context of inflammation and cell death. In the past decade, a variety of chemical substances have been reported to induce pannexin1 channel opening, including metals, chelating agents, particulate matter, nanoparticles and drugs. While the pathophysiological aspects of pannexin1 channel communication have been reviewed on many previous occasions, the present paper intends to provide a short perspective in order to motivate research that will advance mechanistic understanding of the roles of pannexin1 signaling in chemical toxicity.
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Affiliation(s)
- Mathieu Vinken
- Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium.
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3
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Neurodegeneration in Multiple Sclerosis: The Role of Nrf2-Dependent Pathways. Antioxidants (Basel) 2022; 11:antiox11061146. [PMID: 35740042 PMCID: PMC9219619 DOI: 10.3390/antiox11061146] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/06/2022] [Accepted: 06/08/2022] [Indexed: 12/10/2022] Open
Abstract
Multiple sclerosis (MS) encompasses a chronic, irreversible, and predominantly immune-mediated disease of the central nervous system that leads to axonal degeneration, neuronal death, and several neurological symptoms. Although various immune therapies have reduced relapse rates and the severity of symptoms in relapsing-remitting MS, there is still no cure for this devastating disease. In this brief review, we discuss the role of mitochondria dysfunction in the progression of MS, focused on the possible role of Nrf2 signaling in orchestrating the impairment of critical cellular and molecular aspects such as reactive oxygen species (ROS) management, under neuroinflammation and neurodegeneration in MS. In this scenario, we propose a new potential downstream signaling of Nrf2 pathway, namely the opening of hemichannels and pannexons. These large-pore channels are known to modulate glial/neuronal function and ROS production as they are permeable to extracellular Ca2+ and release potentially harmful transmitters to the synaptic cleft. In this way, the Nrf2 dysfunction impairs not only the bioenergetics and metabolic properties of glial cells but also the proper antioxidant defense and energy supply that they provide to neurons.
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Marenna S, Huang SC, Dalla Costa G, d’Isa R, Castoldi V, Rossi E, Comi G, Leocani L. Visual Evoked Potentials to Monitor Myelin Cuprizone-Induced Functional Changes. Front Neurosci 2022; 16:820155. [PMID: 35495042 PMCID: PMC9051229 DOI: 10.3389/fnins.2022.820155] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 03/07/2022] [Indexed: 11/17/2022] Open
Abstract
The visual system is one of the most accessible routes to study the central nervous system under pathological conditions, such as in multiple sclerosis (MS). Non-invasive visual evoked potential (VEP) and optical coherence tomography (OCT) were used to assess visual function and neuroretinal thickness in C57BL/6 taking 0.2% cuprizone for 7 weeks and at 5, 8, 12, and 15 days after returning to a normal diet. VEPs were significantly delayed starting from 4 weeks on cuprizone, with progressive recovery off cuprizone, becoming significant at day 8, complete at day 15. In contrast, OCT and neurofilament staining showed no significant axonal thinning. Optic nerve histology indicated that whilst there was significant myelin loss at 7 weeks on the cuprizone diet compared with healthy mice, at 15 days off cuprizone diet demyelination was significantly less severe. The number of Iba 1+ cells was found increased in cuprizone mice at 7 weeks on and 15 days off cuprizone. The combined use of VEPs and OCT allowed us to characterize non-invasively, in vivo, the functional and structural changes associated with demyelination and remyelination in a preclinical model of MS. This approach contributes to the non-invasive study of possible effective treatments to promote remyelination in demyelinating pathologies.
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Affiliation(s)
- Silvia Marenna
- Experimental Neurophysiology Unit, Institute of Experimental Neurology (INSPE), IRCCS-Scientific Institute San Raffaele, Milan, Italy
| | - Su-Chun Huang
- Experimental Neurophysiology Unit, Institute of Experimental Neurology (INSPE), IRCCS-Scientific Institute San Raffaele, Milan, Italy
| | - Gloria Dalla Costa
- Experimental Neurophysiology Unit, Institute of Experimental Neurology (INSPE), IRCCS-Scientific Institute San Raffaele, Milan, Italy
- Faculty of Medicine, Vita-Salute San Raffaele University, Milan, Italy
| | - Raffaele d’Isa
- Experimental Neurophysiology Unit, Institute of Experimental Neurology (INSPE), IRCCS-Scientific Institute San Raffaele, Milan, Italy
| | - Valerio Castoldi
- Experimental Neurophysiology Unit, Institute of Experimental Neurology (INSPE), IRCCS-Scientific Institute San Raffaele, Milan, Italy
| | - Elena Rossi
- Experimental Neurophysiology Unit, Institute of Experimental Neurology (INSPE), IRCCS-Scientific Institute San Raffaele, Milan, Italy
| | - Giancarlo Comi
- Faculty of Medicine, Vita-Salute San Raffaele University, Milan, Italy
- Casa di Cura Privata del Policlinico, Milan, Italy
| | - Letizia Leocani
- Experimental Neurophysiology Unit, Institute of Experimental Neurology (INSPE), IRCCS-Scientific Institute San Raffaele, Milan, Italy
- Faculty of Medicine, Vita-Salute San Raffaele University, Milan, Italy
- *Correspondence: Letizia Leocani,
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Enrich-Bengoa J, Manich G, Valente T, Sanchez-Molina P, Almolda B, Solà C, Saura J, González B, Castellano B, Perálvarez-Marín A. TRPV2: A Key Player in Myelination Disorders of the Central Nervous System. Int J Mol Sci 2022; 23:ijms23073617. [PMID: 35408977 PMCID: PMC8999035 DOI: 10.3390/ijms23073617] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 01/27/2023] Open
Abstract
Transient potential receptor vanilloid 2 (TRPV2) is widely expressed through the nervous system and specifically found in neuronal subpopulations and some glial cells. TRPV2 is known to be sensitized by methionine oxidation, which results from inflammation. Here we aim to characterize the expression and regulation of TRPV2 in myelination pathologies, such as hypomyelination and demyelination. We validated the interaction between TRPV2 and its putative interactor Opalin, an oligodendrocyte marker, in mixed glial cultures under pro- and anti-inflammatory conditions. Then, we characterized TRPV2 time-course expression in experimental animal models of hypomyelination (jimpy mice) and de-/remyelination (cuprizone intoxication and experimental autoimmune encephalomyelitis (EAE)). TRPV2 showed upregulation associated with remyelination, inflammation in cuprizone and EAE models, and downregulation in hypomyelinated jimpy mice. TRPV2 expression was altered in human samples of multiple sclerosis (MS) patients. Additionally, we analyzed the expression of methionine sulfoxide reductase A (MSRA), an enzyme that reduces oxidated methionines in TRPV2, which we found increased in inflammatory conditions. These results suggest that TRPV2 may be a key player in myelination in accordance with the recapitulation hypothesis, and that it may become an interesting clinical target in the treatment of demyelination disorders.
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Affiliation(s)
- Jennifer Enrich-Bengoa
- Biophysics Unit, Department of Biochemistry and Molecular Biology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain;
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
| | - Gemma Manich
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Tony Valente
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
- Research Group on Methodology, Methods, Models and Outcomes of Health and Social Sciences (M3O), Experimental Sciences and Methodological Department, Faculty of Health Sciences and Welfare, University of Vic-Central University of Catalonia (UVic-UCC), 08500 Vic, Catalonia, Spain
| | - Paula Sanchez-Molina
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Beatriz Almolda
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Carme Solà
- Department of Cerebral Ischemia and Neurodegeneration, Institut D’Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones Científicas (CSIC), Institut D’Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS), 08036 Barcelona, Catalonia, Spain;
| | - Josep Saura
- Biochemistry and Molecular Biology Unit, School of Medicine, Institut D’Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS), University of Barcelona, 08036 Barcelona, Catalonia, Spain;
| | - Berta González
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Bernardo Castellano
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Alex Perálvarez-Marín
- Biophysics Unit, Department of Biochemistry and Molecular Biology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain;
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Correspondence: ; Tel.: +34-93-581-4504
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Caufriez A, Böck D, Martin C, Ballet S, Vinken M. Peptide-based targeting of connexins and pannexins for therapeutic purposes. Expert Opin Drug Discov 2020; 15:1213-1222. [PMID: 32539572 DOI: 10.1080/17460441.2020.1773787] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
INTRODUCTION Connexin and pannexin (hemi)channels play an important role in paracrine and autocrine signaling pathways. The opening of these cellular pores is linked to a wide range of diseases. Therefore, pharmacological closing of connexin and pannexin (hemi)channels seems a promising therapeutic strategy. However, the currently available inhibitors cope with recurring problems concerning selectivity, specificity, stability and/or solubility. AREAS COVERED A number of peptides that mimic specific regions in the native sequence of connexins and pannexins have the potential to overcome some of these hurdles. In this paper, an overview is provided on these peptide-based inhibitors of connexin and pannexin (hemi)channels for therapeutic purposes. The authors also provide the reader with their expert perspectives on the future of these peptide-based inhibitors. EXPERT OPINION Peptide mimetics can become valuable tools in the treatment of connexin-related and pannexin-related diseases. This can be made possible provided that available peptides are optimized, and new peptide mimetics are designed based on knowledge of the mechanisms underlying the gating control of connexin and pannexin (hemi)channels.
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Affiliation(s)
- Anne Caufriez
- Department of in Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel , 1090, Brussels, Belgium
| | - Denise Böck
- Department of in Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel , 1090, Brussels, Belgium
| | - Charlotte Martin
- Department of Organic Chemistry, Vrije Universiteit Brussel , 1050, Brussels, Belgium
| | - Steven Ballet
- Department of Organic Chemistry, Vrije Universiteit Brussel , 1050, Brussels, Belgium
| | - Mathieu Vinken
- Department of in Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel , 1090, Brussels, Belgium
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Ortiz FC, Puebla C. Pannexin 1-based channels activity as a novel regulator of multiple sclerosis progression. Neural Regen Res 2020; 15:65-66. [PMID: 31535649 PMCID: PMC6862397 DOI: 10.4103/1673-5374.264450] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Fernando C Ortiz
- Mechanisms on Myelin Formation and Repair Laboratory, Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
| | - Carlos Puebla
- Cellular Physiology Laboratory, Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
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8
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Vejar S, Oyarzún JE, Retamal MA, Ortiz FC, Orellana JA. Connexin and Pannexin-Based Channels in Oligodendrocytes: Implications in Brain Health and Disease. Front Cell Neurosci 2019; 13:3. [PMID: 30760982 PMCID: PMC6361860 DOI: 10.3389/fncel.2019.00003] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/07/2019] [Indexed: 11/13/2022] Open
Abstract
Oligodendrocytes are the myelin forming cells in the central nervous system (CNS). In addition to this main physiological function, these cells play key roles by providing energy substrates to neurons as well as information required to sustain proper synaptic transmission and plasticity at the CNS. The latter requires a fine coordinated intercellular communication with neurons and other glial cell types, including astrocytes. In mammals, tissue synchronization is mainly mediated by connexins and pannexins, two protein families that underpin the communication among neighboring cells through the formation of different plasma membrane channels. At one end, gap junction channels (GJCs; which are exclusively formed by connexins in vertebrates) connect the cytoplasm of contacting cells allowing electrical and metabolic coupling. At the other end, hemichannels and pannexons (which are formed by connexins and pannexins, respectively) communicate the intra- and extracellular compartments, serving as diffusion pathways of ions and small molecules. Here, we briefly review the current knowledge about the expression and function of hemichannels, pannexons and GJCs in oligodendrocytes, as well as the evidence regarding the possible role of these channels in metabolic and synaptic functions at the CNS. In particular, we focus on oligodendrocyte-astrocyte coupling during axon metabolic support and its implications in brain health and disease.
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Affiliation(s)
- Sebastián Vejar
- Mechanisms of Myelin Formation and Repair Laboratory, Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
| | - Juan E Oyarzún
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Investigación y Estudio del Consumo de Alcohol en Adolescentes, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mauricio A Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile.,Department of Cell Physiology and Molecular Biophysics, and Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Fernando C Ortiz
- Mechanisms of Myelin Formation and Repair Laboratory, Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
| | - Juan A Orellana
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Investigación y Estudio del Consumo de Alcohol en Adolescentes, Pontificia Universidad Católica de Chile, Santiago, Chile
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Hainz N, Wolf S, Beck A, Wagenpfeil S, Tschernig T, Meier C. Probenecid arrests the progression of pronounced clinical symptoms in a mouse model of multiple sclerosis. Sci Rep 2017; 7:17214. [PMID: 29222419 PMCID: PMC5722901 DOI: 10.1038/s41598-017-17517-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 11/27/2017] [Indexed: 12/05/2022] Open
Abstract
While it has been established that Probenecid (PBN) prevents the onset of experimental autoimmune encephalomyelitis (EAE) in mice, it is not clear whether it has any effect on already manifest EAE. The aim of this study was therefore to analyze the therapeutic effect of PBN in pronounced EAE. Mice with manifest clinical symptoms of EAE were either treated with PBN or solvent for 20 days, or they were left untreated. The clinical symptoms were monitored daily. Inflammation, demyelination and oligodendrocyte numbers were determined in the spinal cord. We were able to demonstrate that PBN not only significantly prolonged survival but also prevented the progression of clinical symptoms in the EAE model of multiple sclerosis. In addition, we were able to show that PBN reduced inflammation, T cell infiltration and oligodendrocyte cell loss. PBN was previously shown to inhibit – among other targets – pannexin channels. As pannexin channels provide conduits for ATP, are associated with the inflammasome, and act as “find me-signals” in the process of apoptosis, inhibition of pannexins via PBN might contribute to the PBN-effects observed in this study. The beneficial and therapeutic effects of PBN in the context of EAE demonstrate an intriguing link between PBN and neuroinflammation, which might foster translational interest.
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Affiliation(s)
- Nadine Hainz
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Sandra Wolf
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Artjom Beck
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Stefan Wagenpfeil
- Institute for Medical Biometry, Epidemiology & Medical Informatics, Saarland University, Homburg/Saar, Germany
| | - Thomas Tschernig
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Carola Meier
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany.
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