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Su Y, Verkhratsky A, Yi C. Targeting connexins: possible game changer in managing neuropathic pain? Trends Mol Med 2024:S1471-4914(24)00064-9. [PMID: 38594094 DOI: 10.1016/j.molmed.2024.03.009] [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: 01/23/2024] [Revised: 03/08/2024] [Accepted: 03/18/2024] [Indexed: 04/11/2024]
Abstract
Neuropathic pain is a chronic debilitating condition caused by nerve injury or a variety of diseases. At the core of neuropathic pain lies the aberrant neuronal excitability in the peripheral and/or central nervous system (PNS and CNS). Enhanced connexin expression and abnormal activation of connexin-assembled gap junctional channels are prominent in neuropathic pain along with reactive gliosis, contributing to neuronal hypersensitivity and hyperexcitability. In this review, we delve into the current understanding of how connexin expression and function contribute to the pathogenesis and pathophysiology of neuropathic pain and argue for connexins as potential therapeutic targets for neuropathic pain management.
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Affiliation(s)
- Yixun Su
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
| | - Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK; Achucarro Center for Neuroscience, IKERBASQUE, Bilbao, Spain; Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania; Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China.
| | - Chenju Yi
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Guangzhou, China; Shenzhen Key Laboratory of Chinese Medicine Active substance screening and Translational Research, Shenzhen, China.
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2
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Alarcon-Martinez L, Shiga Y, Villafranca-Baughman D, Cueva Vargas JL, Vidal Paredes IA, Quintero H, Fortune B, Danesh-Meyer H, Di Polo A. Neurovascular dysfunction in glaucoma. Prog Retin Eye Res 2023; 97:101217. [PMID: 37778617 DOI: 10.1016/j.preteyeres.2023.101217] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/23/2023] [Accepted: 09/25/2023] [Indexed: 10/03/2023]
Abstract
Retinal ganglion cells, the neurons that die in glaucoma, are endowed with a high metabolism requiring optimal provision of oxygen and nutrients to sustain their activity. The timely regulation of blood flow is, therefore, essential to supply firing neurons in active areas with the oxygen and glucose they need for energy. Many glaucoma patients suffer from vascular deficits including reduced blood flow, impaired autoregulation, neurovascular coupling dysfunction, and blood-retina/brain-barrier breakdown. These processes are tightly regulated by a community of cells known as the neurovascular unit comprising neurons, endothelial cells, pericytes, Müller cells, astrocytes, and microglia. In this review, the neurovascular unit takes center stage as we examine the ability of its members to regulate neurovascular interactions and how their function might be altered during glaucomatous stress. Pericytes receive special attention based on recent data demonstrating their key role in the regulation of neurovascular coupling in physiological and pathological conditions. Of particular interest is the discovery and characterization of tunneling nanotubes, thin actin-based conduits that connect distal pericytes, which play essential roles in the complex spatial and temporal distribution of blood within the retinal capillary network. We discuss cellular and molecular mechanisms of neurovascular interactions and their pathophysiological implications, while highlighting opportunities to develop strategies for vascular protection and regeneration to improve functional outcomes in glaucoma.
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Affiliation(s)
- Luis Alarcon-Martinez
- Department of Neuroscience, Université de Montréal, PO Box 6128, Station centre-ville, Montreal, QC, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montreal, QC, Canada; Centre for Eye Research Australia, University of Melbourne, Melbourne, Australia
| | - Yukihiro Shiga
- Department of Neuroscience, Université de Montréal, PO Box 6128, Station centre-ville, Montreal, QC, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montreal, QC, Canada
| | - Deborah Villafranca-Baughman
- Department of Neuroscience, Université de Montréal, PO Box 6128, Station centre-ville, Montreal, QC, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montreal, QC, Canada
| | - Jorge L Cueva Vargas
- Department of Neuroscience, Université de Montréal, PO Box 6128, Station centre-ville, Montreal, QC, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montreal, QC, Canada
| | - Isaac A Vidal Paredes
- Department of Neuroscience, Université de Montréal, PO Box 6128, Station centre-ville, Montreal, QC, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montreal, QC, Canada
| | - Heberto Quintero
- Department of Neuroscience, Université de Montréal, PO Box 6128, Station centre-ville, Montreal, QC, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montreal, QC, Canada
| | - Brad Fortune
- Discoveries in Sight Research Laboratories, Devers Eye Institute and Legacy Research Institute, Legacy Healthy, Portland, OR, USA
| | - Helen Danesh-Meyer
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Adriana Di Polo
- Department of Neuroscience, Université de Montréal, PO Box 6128, Station centre-ville, Montreal, QC, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montreal, QC, Canada.
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3
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Huang Q, Sha W, Gu Q, Wang J, Zhu Y, Xu T, Xu Z, Yan F, Lin X, Tian S. Inhibition of Connexin43 Improves the Recovery of Spinal Cord Injury Against Ferroptosis via the SLC7A11/GPX4 Pathway. Neuroscience 2023; 526:121-134. [PMID: 37391124 DOI: 10.1016/j.neuroscience.2023.06.017] [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: 02/24/2023] [Revised: 06/15/2023] [Accepted: 06/20/2023] [Indexed: 07/02/2023]
Abstract
Ferroptosis plays a key role in the process of spinal cord injury (SCI). As a signal amplifier, connexin 43 (CX43) participates in cell death signal transduction and aggravates the propagation of injury. However, it remains unclear whether CX43 plays a regulatory role in ferroptosis after SCI. The SCI rat model was established by an Infinite Vertical Impactor to investigate the role of CX43 in SCI-induced ferroptosis. Ferrostatin-1 (Fer-1), an inhibitor of ferroptosis, and a CX43-specific inhibitor (Gap27) were administered by intraperitoneal injection. Behavioral analysis was assessed according to the Basso-Beattie-Bresnahan (BBB) Motor Rating Scale and the inclined plate test. The levels of ferroptosis-related proteins were estimated by qRT-PCR and western blotting, while the histopathology of neuronal injury induced by SCI was evaluated by immunofluorescence, Nissl, FJB and Perl's Blue staining. Meanwhile, transmission electron microscopy was used to observe the ultrastructural changes characteristic of ferroptosis. Gap27 strongly inhibited ferroptosis and therefore improved the functional recovery of SCI, which was similar to the treatment of Fer-1. Notably, the inhibition of CX43 decreased P-mTOR/mTOR expression and reversed the decrease in SLC7A11 induced by SCI. As a result, the levels of GPX4 and glutathione (GSH) increased, while the levels of the lipid peroxidation products 4-hydroxynonenal (4-HNE) and malondialdehyde (MDA) decreased. Together, inhibition of CX43 could alleviate ferroptosis after SCI. These findings reveal a potential mechanism of the neuroprotective role of CX43 after SCI and provide a new theoretical basis for clinical transformation and application.
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Affiliation(s)
- Qun Huang
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China; Orthopaedics Laboratory, The First People's Hospital of Zhangjiagang City, Suzhou 215600, China
| | - Weiping Sha
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China; Orthopaedics Laboratory, The First People's Hospital of Zhangjiagang City, Suzhou 215600, China
| | - Qi Gu
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China; Orthopaedics Laboratory, The First People's Hospital of Zhangjiagang City, Suzhou 215600, China
| | - Jin Wang
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China; Orthopaedics Laboratory, The First People's Hospital of Zhangjiagang City, Suzhou 215600, China
| | - Yi Zhu
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China; Orthopaedics Laboratory, The First People's Hospital of Zhangjiagang City, Suzhou 215600, China
| | - Tianli Xu
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China; Orthopaedics Laboratory, The First People's Hospital of Zhangjiagang City, Suzhou 215600, China
| | - Zhenhua Xu
- Department of Anesthesiology, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China
| | - Fei Yan
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China
| | - Xiaolong Lin
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China; Orthopaedics Laboratory, The First People's Hospital of Zhangjiagang City, Suzhou 215600, China.
| | - Shoujin Tian
- Department of Orthopaedic Surgery, Zhangjiagang Hospital affiliated to Soochow University, Suzhou 215600, China; Orthopaedics Laboratory, The First People's Hospital of Zhangjiagang City, Suzhou 215600, China.
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4
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Rodriguez-Jimenez FJ, Jendelova P, Erceg S. The activation of dormant ependymal cells following spinal cord injury. Stem Cell Res Ther 2023; 14:175. [PMID: 37408068 DOI: 10.1186/s13287-023-03395-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 06/02/2023] [Indexed: 07/07/2023] Open
Abstract
Ependymal cells, a dormant population of ciliated progenitors found within the central canal of the spinal cord, undergo significant alterations after spinal cord injury (SCI). Understanding the molecular events that induce ependymal cell activation after SCI represents the first step toward controlling the response of the endogenous regenerative machinery in damaged tissues. This response involves the activation of specific signaling pathways in the spinal cord that promotes self-renewal, proliferation, and differentiation. We review our current understanding of the signaling pathways and molecular events that mediate the SCI-induced activation of ependymal cells by focusing on the roles of some cell adhesion molecules, cellular membrane receptors, ion channels (and their crosstalk), and transcription factors. An orchestrated response regulating the expression of receptors and ion channels fine-tunes and coordinates the activation of ependymal cells after SCI or cell transplantation. Understanding the major players in the activation of ependymal cells may help us to understand whether these cells represent a critical source of cells contributing to cellular replacement and tissue regeneration after SCI. A more complete understanding of the role and function of individual signaling pathways in endogenous spinal cord progenitors may foster the development of novel targeted therapies to induce the regeneration of the injured spinal cord.
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Affiliation(s)
- Francisco Javier Rodriguez-Jimenez
- Stem Cell Therapies in Neurodegenerative Diseases Lab, Research Center "Principe Felipe", C/Eduardo Primo Yúfera 3, 46012, Valencia, Spain.
| | - Pavla Jendelova
- Department of Neuroregeneration, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czech Republic
| | - Slaven Erceg
- Stem Cell Therapies in Neurodegenerative Diseases Lab, Research Center "Principe Felipe", C/Eduardo Primo Yúfera 3, 46012, Valencia, Spain.
- National Stem Cell Bank - Valencia Node, Research Center "Principe Felipe", C/Eduardo Primo Yúfera 3, 46012, Valencia, Spain.
- Department of Neuroregeneration, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czech Republic.
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Maran JJ, Adesina MM, Green CR, Kwakowsky A, Mugisho OO. The central role of the NLRP3 inflammasome pathway in the pathogenesis of age-related diseases in the eye and the brain. Ageing Res Rev 2023; 88:101954. [PMID: 37187367 DOI: 10.1016/j.arr.2023.101954] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/08/2023] [Accepted: 05/12/2023] [Indexed: 05/17/2023]
Abstract
With increasing age, structural changes occur in the eye and brain. Neuronal death, inflammation, vascular disruption, and microglial activation are among many of the pathological changes that can occur during ageing. Furthermore, ageing individuals are at increased risk of developing neurodegenerative diseases in these organs, including Alzheimer's disease (AD), Parkinson's disease (PD), glaucoma and age-related macular degeneration (AMD). Although these diseases pose a significant global public health burden, current treatment options focus on slowing disease progression and symptomatic control rather than targeting underlying causes. Interestingly, recent investigations have proposed an analogous aetiology between age-related diseases in the eye and brain, where a process of chronic low-grade inflammation is implicated. Studies have suggested that patients with AD or PD are also associated with an increased risk of AMD, glaucoma, and cataracts. Moreover, pathognomonic amyloid-β and α-synuclein aggregates, which accumulate in AD and PD, respectively, can be found in ocular parenchyma. In terms of a common molecular pathway that underpins these diseases, the nucleotide-binding domain, leucine-rich-containing family, and pyrin domain-containing-3 (NLRP3) inflammasome is thought to play a vital role in the manifestation of all these diseases. This review summarises the current evidence regarding cellular and molecular changes in the brain and eye with age, similarities between ocular and cerebral age-related diseases, and the role of the NLRP3 inflammasome as a critical mediator of disease propagation in the eye and the brain during ageing.
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Affiliation(s)
- Jack J Maran
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology and the New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Moradeke M Adesina
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology and the New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Colin R Green
- Department of Ophthalmology and the New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Andrea Kwakowsky
- Pharmacology and Therapeutics, School of Medicine, Galway Neuroscience Centre, University of Galway, Galway, Ireland
| | - Odunayo O Mugisho
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology and the New Zealand National Eye Centre, University of Auckland, New Zealand.
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Yang Q, Jiang M, Xu S, Yang L, Yang P, Song Y, Zhu H, Wang Y, Sun Y, Yan C, Yuan Z, Liu X, Bai Z. Mirror image pain mediated by D2 receptor regulation of astrocytic Cx43 phosphorylation and channel opening. Biochim Biophys Acta Mol Basis Dis 2023; 1869:166657. [PMID: 36716897 DOI: 10.1016/j.bbadis.2023.166657] [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: 09/26/2022] [Revised: 12/21/2022] [Accepted: 01/20/2023] [Indexed: 01/29/2023]
Abstract
Mirror image pain (MIP), a clinical syndrome of contralateral pain hypersensitivity caused by unilateral injury, has been identified in various neuropathological conditions. Gap junctional protein Connexin 43 (Cx43), its phosphorylation levels and dopamine D2 receptor (DRD2) play key integrating roles in pain processing. We presume D2DR activity may affect Cx43 hemichannel opening via Cx43 phosphorylation levels to regulate MIP. This study shows that spinal astrocytic Cx43 directly interacts with DRD2 to mediate MIP. DRD2 and Cx43 expression levels were asymmetrically elevated in bilateral spinal during MIP, and DRD2 modulated the opening of primary astrocytic Cx43 hemichannels. Furthermore, Cx43 phosphorylation at Ser373 was increased during MIP, but decreased in DRD2 knockout (KO) mice. Finally, activation of spinal protein kinase A (PKA) altered the expression of Cx43 and its phosphorylation bilaterally, thus reversing the analgesic effect in DRD2 KO mice. Together, these data reveal that spinal Cx43 phosphorylation and channel opening are regulated by DRD2 via PKA activation, and that spinal Cx43 and DRD2 are key molecular sensors mediating mirror image pain.
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Affiliation(s)
- Qinghu Yang
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China; Yanan Engineering & Technological Research Centre for Resource Peptide Drugs, Yanan 716000, China; Yanan Key Laboratory for Neural Immuno-Tumor and Stem Cell, Yanan 716000, China
| | - Ming Jiang
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China; Yanan Engineering & Technological Research Centre for Resource Peptide Drugs, Yanan 716000, China; Yanan Key Laboratory for Neural Immuno-Tumor and Stem Cell, Yanan 716000, China
| | - Sen Xu
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China
| | - Liang Yang
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China; Yanan Engineering & Technological Research Centre for Resource Peptide Drugs, Yanan 716000, China; Yanan Key Laboratory for Neural Immuno-Tumor and Stem Cell, Yanan 716000, China
| | - Pan Yang
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China
| | - Yutian Song
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China
| | - Hongni Zhu
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China
| | - Yu Wang
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China
| | - Yahan Sun
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China
| | - Chengxiang Yan
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China
| | - Zhaoyue Yuan
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China
| | - Xia Liu
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China; Yanan Engineering & Technological Research Centre for Resource Peptide Drugs, Yanan 716000, China; Yanan Key Laboratory for Neural Immuno-Tumor and Stem Cell, Yanan 716000, China.
| | - Zhantao Bai
- School of Life Science & Research Center for Natural Peptide Drugs, Shaanxi Engineering & Technological Research Centre for Conservation & Utilization of Regional Biological Resources, Yanan University, Yanan 716000, China; Yanan Engineering & Technological Research Centre for Resource Peptide Drugs, Yanan 716000, China; Yanan Key Laboratory for Neural Immuno-Tumor and Stem Cell, Yanan 716000, China.
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7
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Crystal Chan SH, Griffin JM, Clemett CA, Brimble MA, O’Carroll SJ, Harris PWR. Synthesis and Biological Evaluation of Termini-Modified and Cyclic Variants of the Connexin43 Inhibitor Peptide5. Front Chem 2022; 10:877618. [PMID: 36176893 PMCID: PMC9513234 DOI: 10.3389/fchem.2022.877618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 05/20/2022] [Indexed: 11/25/2022] Open
Abstract
Peptide5 is a 12–amino acid mimetic peptide that corresponds to a region of the extracellular loop 2 (EL2) of connexin43. Peptide5 regulates both cellular communication with the cytoplasm (hemichannels) and cell-to-cell communication (gap junctions), and both processes are implicated in neurological pathologies. To address the poor in vivo stability of native peptide5 and to improve its activity, twenty-five novel peptide5 mimetics were designed and synthesized. All the analogues underwent biological evaluation as a hemichannel blocker and as a gap junction disruptor, and several were assessed for stability in human serum. From this study, it was established that several acylations on the N-terminus were tolerated in the hemichannel assay. However, the replacement of the L-Lys with an N-methylated L-Lys to give H-VDCFLSRPTE-N-MeKT-OH showed good hemichannel and gap junction activity and was more stable in human serum. The cyclic peptide variants generally were not tolerated in either the hemichannel and gap junction assay although several possessed outstanding stability in human serum.
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Affiliation(s)
| | - Jarred M. Griffin
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Connor A. Clemett
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Margaret A. Brimble
- School of Chemical Sciences, The University of Auckland, Auckland, New Zealand
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland, New Zealand
| | - Simon J. O’Carroll
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- *Correspondence: Simon J. O’Carroll, ; Paul W. R. Harris,
| | - Paul W. R. Harris
- School of Chemical Sciences, The University of Auckland, Auckland, New Zealand
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland, New Zealand
- *Correspondence: Simon J. O’Carroll, ; Paul W. R. Harris,
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Peng B, Xu C, Wang S, Zhang Y, Li W. The Role of Connexin Hemichannels in Inflammatory Diseases. BIOLOGY 2022; 11:biology11020237. [PMID: 35205103 PMCID: PMC8869213 DOI: 10.3390/biology11020237] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 01/28/2022] [Accepted: 02/01/2022] [Indexed: 02/04/2023]
Abstract
The connexin protein family consists of approximately 20 members, and is well recognized as the structural unit of the gap junction channels that perforate the plasma membranes of coupled cells and, thereby, mediate intercellular communication. Gap junctions are assembled by two preexisting hemichannels on the membranes of apposing cells. Non-junctional connexin hemichannels (CxHC) provide a conduit between the cell interior and the extracellular milieu, and are believed to be in a protectively closed state under physiological conditions. The development and characterization of the peptide mimetics of the amino acid sequences of connexins have resulted in the development of a panel of blockers with a higher selectivity for CxHC, which have become important tools for defining the role of CxHC in various biological processes. It is increasingly clear that CxHC can be induced to open by pathogen-associated molecular patterns. The opening of CxHC facilitates the release of damage-associated molecular patterns, a class of endogenous molecules that are critical for the pathogenesis of inflammatory diseases. The blockade of CxHC leads to attenuated inflammation, reduced tissue injury and improved organ function in human and animal models of about thirty inflammatory diseases and disorders. These findings demonstrate that CxHC may contribute to the intensification of inflammation, and serve as a common target in the treatments of various inflammatory diseases. In this review, we provide an update on the progress in the understanding of CxHC, with a focus on the role of these channels in inflammatory diseases.
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Affiliation(s)
| | | | | | - Yijie Zhang
- Correspondence: (Y.Z.); (W.L.); Tel.: +86-13903782431 (Y.Z.); +86-17839250252 (W.L.)
| | - Wei Li
- Correspondence: (Y.Z.); (W.L.); Tel.: +86-13903782431 (Y.Z.); +86-17839250252 (W.L.)
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King DR, Sedovy MW, Leng X, Xue J, Lamouille S, Koval M, Isakson BE, Johnstone SR. Mechanisms of Connexin Regulating Peptides. Int J Mol Sci 2021; 22:ijms221910186. [PMID: 34638526 PMCID: PMC8507914 DOI: 10.3390/ijms221910186] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/16/2021] [Accepted: 09/17/2021] [Indexed: 12/22/2022] Open
Abstract
Gap junctions (GJ) and connexins play integral roles in cellular physiology and have been found to be involved in multiple pathophysiological states from cancer to cardiovascular disease. Studies over the last 60 years have demonstrated the utility of altering GJ signaling pathways in experimental models, which has led to them being attractive targets for therapeutic intervention. A number of different mechanisms have been proposed to regulate GJ signaling, including channel blocking, enhancing channel open state, and disrupting protein-protein interactions. The primary mechanism for this has been through the design of numerous peptides as therapeutics, that are either currently in early development or are in various stages of clinical trials. Despite over 25 years of research into connexin targeting peptides, the overall mechanisms of action are still poorly understood. In this overview, we discuss published connexin targeting peptides, their reported mechanisms of action, and the potential for these molecules in the treatment of disease.
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Affiliation(s)
- D. Ryan King
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
| | - Meghan W. Sedovy
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
- Translational Biology, Medicine, and Health Graduate Program, Virginia Tech, Blacksburg, VA 24061, USA
| | - Xinyan Leng
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
| | - Jianxiang Xue
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA; (J.X.); (B.E.I.)
| | - Samy Lamouille
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
- Center for Vascular and Heart Research, Virginia Tech, Roanoke, VA 24016, USA
| | - Michael Koval
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA;
| | - Brant E. Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA; (J.X.); (B.E.I.)
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Scott R. Johnstone
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
- Center for Vascular and Heart Research, Virginia Tech, Roanoke, VA 24016, USA
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
- Correspondence:
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Prieto-Villalobos J, Alvear TF, Liberona A, Lucero CM, Martínez-Araya CJ, Balmazabal J, Inostroza CA, Ramírez G, Gómez GI, Orellana JA. Astroglial Hemichannels and Pannexons: The Hidden Link between Maternal Inflammation and Neurological Disorders. Int J Mol Sci 2021; 22:ijms22179503. [PMID: 34502412 PMCID: PMC8430734 DOI: 10.3390/ijms22179503] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 08/30/2021] [Accepted: 08/30/2021] [Indexed: 12/11/2022] Open
Abstract
Maternal inflammation during pregnancy causes later-in-life alterations of the offspring’s brain structure and function. These abnormalities increase the risk of developing several psychiatric and neurological disorders, including schizophrenia, intellectual disability, bipolar disorder, autism spectrum disorder, microcephaly, and cerebral palsy. Here, we discuss how astrocytes might contribute to postnatal brain dysfunction following maternal inflammation, focusing on the signaling mediated by two families of plasma membrane channels: hemi-channels and pannexons. [Ca2+]i imbalance linked to the opening of astrocytic hemichannels and pannexons could disturb essential functions that sustain astrocytic survival and astrocyte-to-neuron support, including energy and redox homeostasis, uptake of K+ and glutamate, and the delivery of neurotrophic factors and energy-rich metabolites. Both phenomena could make neurons more susceptible to the harmful effect of prenatal inflammation and the experience of a second immune challenge during adulthood. On the other hand, maternal inflammation could cause excitotoxicity by producing the release of high amounts of gliotransmitters via astrocytic hemichannels/pannexons, eliciting further neuronal damage. Understanding how hemichannels and pannexons participate in maternal inflammation-induced brain abnormalities could be critical for developing pharmacological therapies against neurological disorders observed in the offspring.
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Affiliation(s)
- Juan Prieto-Villalobos
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8330024, Chile; (J.P.-V.); (T.F.A.); (A.L.); (C.J.M.-A.); (J.B.); (C.A.I.); (G.R.)
| | - Tanhia F. Alvear
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8330024, Chile; (J.P.-V.); (T.F.A.); (A.L.); (C.J.M.-A.); (J.B.); (C.A.I.); (G.R.)
| | - Andrés Liberona
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8330024, Chile; (J.P.-V.); (T.F.A.); (A.L.); (C.J.M.-A.); (J.B.); (C.A.I.); (G.R.)
| | - Claudia M. Lucero
- Institute of Biomedical Sciences, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago 8910060, Chile; (C.M.L.); (G.I.G.)
| | - Claudio J. Martínez-Araya
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8330024, Chile; (J.P.-V.); (T.F.A.); (A.L.); (C.J.M.-A.); (J.B.); (C.A.I.); (G.R.)
| | - Javiera Balmazabal
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8330024, Chile; (J.P.-V.); (T.F.A.); (A.L.); (C.J.M.-A.); (J.B.); (C.A.I.); (G.R.)
| | - Carla A. Inostroza
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8330024, Chile; (J.P.-V.); (T.F.A.); (A.L.); (C.J.M.-A.); (J.B.); (C.A.I.); (G.R.)
| | - Gigliola Ramírez
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8330024, Chile; (J.P.-V.); (T.F.A.); (A.L.); (C.J.M.-A.); (J.B.); (C.A.I.); (G.R.)
| | - Gonzalo I. Gómez
- Institute of Biomedical Sciences, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago 8910060, Chile; (C.M.L.); (G.I.G.)
| | - Juan A. Orellana
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8330024, Chile; (J.P.-V.); (T.F.A.); (A.L.); (C.J.M.-A.); (J.B.); (C.A.I.); (G.R.)
- Correspondence: ; Tel.: +56-23548105
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11
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Retamal MA, Fernandez-Olivares A, Stehberg J. Over-activated hemichannels: A possible therapeutic target for human diseases. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166232. [PMID: 34363932 DOI: 10.1016/j.bbadis.2021.166232] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 07/21/2021] [Accepted: 07/26/2021] [Indexed: 12/14/2022]
Abstract
In our body, all the cells are constantly sharing chemical and electrical information with other cells. This intercellular communication allows them to respond in a concerted way to changes in the extracellular milieu. Connexins are transmembrane proteins that have the particularity of forming two types of channels; hemichannels and gap junction channels. Under normal conditions, hemichannels allow the controlled release of signaling molecules to the extracellular milieu. However, under certain pathological conditions, over-activated hemichannels can induce and/or exacerbate symptoms. In the last decade, great efforts have been put into developing new tools that can modulate these over-activated hemichannels. Small molecules, antibodies and mimetic peptides have shown a potential for the treatment of human diseases. In this review, we summarize recent findings in the field of hemichannel modulation via specific tools, and how these tools could improve patient outcome in certain pathological conditions.
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Affiliation(s)
- Mauricio A Retamal
- Universidad del Desarrollo, Programa de Comunicación Celular en Cáncer, Santiago, Chile; Universidad del Desarrollo, Centro de Fisiología Celular e Integrativa, Santiago, Chile.
| | | | - Jimmy Stehberg
- Laboratorio de Neurobiología, Instituto de Ciencias Biomédicas, Facultad de medicina y Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
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12
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Shome A, Mugisho OO, Niederer RL, Rupenthal ID. Blocking the inflammasome: A novel approach to treat uveitis. Drug Discov Today 2021; 26:2839-2857. [PMID: 34229084 DOI: 10.1016/j.drudis.2021.06.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/24/2021] [Accepted: 06/30/2021] [Indexed: 12/11/2022]
Abstract
Uveitis is a complex ocular inflammatory disease often accompanied by bacterial or viral infections (infectious uveitis) or underlying autoimmune diseases (non-infectious uveitis). Treatment of the underlying infection along with corticosteroid-mediated suppression of acute inflammation usually resolves infectious uveitis. However, to develop more effective therapies for non-infectious uveitis and to better address acute inflammation in infectious disease, an improved understanding of the underlying inflammatory pathways is needed. In this review, we discuss the disease aetiology, preclinical in vitro and in vivo uveitis models, the role of inflammatory pathways, as well as current and future therapies. In particular, we highlight the involvement of the inflammasome in the development of non-infectious uveitis and how it could be a future target for effective treatment of the disease.
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Affiliation(s)
- Avik Shome
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Odunayo O Mugisho
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Rachael L Niederer
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand; Auckland District Health Board, Auckland, New Zealand
| | - Ilva D Rupenthal
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand.
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13
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Al Mamun A, Wu Y, Monalisa I, Jia C, Zhou K, Munir F, Xiao J. Role of pyroptosis in spinal cord injury and its therapeutic implications. J Adv Res 2021; 28:97-109. [PMID: 33364048 PMCID: PMC7753222 DOI: 10.1016/j.jare.2020.08.004] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 08/05/2020] [Accepted: 08/08/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Currently, spinal cord injury (SCI) is a pathological incident that triggers several neuropathological conditions, leading to the initiation of neuronal damage with several pro-inflammatory mediators' release. However, pyroptosis is recognized as a new programmed cell death mechanism regulated by the stimulation of caspase-1 and/or caspase-11/-4/-5 signaling pathways with a series of inflammatory responses. AIM Our current review concisely summarizes the potential role of pyroptosis-regulated programmed cell death in SCI, according to several molecular and pathophysiological mechanisms. This review also highlights the targeting of pyroptosis signaling pathways and inflammasome components and its therapeutic implications for the treatment of SCI. KEY SCIENTIFIC CONCEPTS Multiple pieces of evidence have illustrated that pyroptosis plays significant roles in cell swelling, plasma membrane lysis, chromatin fragmentation and intracellular pro-inflammatory factors including IL-18 and IL-1β release. In addition, pyroptosis is directly mediated by the recently discovered family of pore-forming protein known as GSDMD. Current investigations have documented that pyroptosis-regulated cell death plays a critical role in the pathogenesis of multiple neurological disorders as well as SCI. Our narrative article suggests that inhibiting the pyroptosis-regulated cell death and inflammasome components could be a promising therapeutic approach for the treatment of SCI in the near future.
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Key Words
- AIM2, Absent in melanoma 2
- ASC, apoptosis-associated speck-like protein
- ATP, Adenosine triphosphate
- BBG, Brilliant blue G
- CCK-8, Cell Counting Kit-8
- CNS, central nervous system
- CO, Carbon monoxide
- CORM-3, Carbon monoxide releasing molecle-3
- Caspase-1
- Cx43, Connexin 43
- DAMPs, Damage-associated molecular patterns
- DRD1, Dopamine Receptor D1
- ECH, Echinacoside
- GSDMD, Gasdermin D
- Gal-3, Galectin-3
- H2O2, Hydrogen peroxide
- HO-1, Heme oxygenase-1
- IL-18, Interleukin-18
- IL-1β, Interleukin-1 beta
- IRE1, Inositol requiring enzyme 1
- JOA, Japanese orthopedics association
- LPS, Lipopolysaccharide
- NDI, Neck data index
- NF-κB, Nuclear factor-kappa B
- NLRP1, NOD-like receptor protein 1
- NLRP1b, NOD-like receptor protein 1b
- NLRP3
- NLRP3, Nucleotide-binding domain-like receptor protein 3
- Neuroinflammation
- Nrf2, Nuclear factor erythroid 2-related factor 2
- OPCs, Oligodendrocyte progenitor cells
- PAMPs, Pathogen-associated molecular patterns
- PRRs, Pattern recognition receptors
- Pyroptosis
- ROS, Reactive oxygen species
- Spinal cord injury
- TLR4, Toll-like receptor 4
- TXNIP, Thioredoxin-interacting protein
- Therapeutic implications
- double stranded DNAIR, Ischemia reperfusion
- si-RNA, Small interfering RNA
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Affiliation(s)
- Abdullah Al Mamun
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035 Zhejiang Province, China
| | - Yanqing Wu
- Institute of Life Sciences, Wenzhou University, Wenzhou, 325035 Zhejiang Province, China
| | - Ilma Monalisa
- Department of Pharmacy, Southeast University, Banani, Dhaka 1213, Bangladesh
| | - Chang Jia
- Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, 325027 Zhejiang Province, China
| | - Kailiang Zhou
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, 325027 Zhejiang Province, China
| | - Fahad Munir
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000 Zhejiang Province, China
| | - Jian Xiao
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035 Zhejiang Province, China
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14
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Acosta ML, Mat Nor MN, Guo CX, Mugisho OO, Coutinho FP, Rupenthal ID, Green CR. Connexin therapeutics: blocking connexin hemichannel pores is distinct from blocking pannexin channels or gap junctions. Neural Regen Res 2021; 16:482-488. [PMID: 32985469 PMCID: PMC7996017 DOI: 10.4103/1673-5374.290097] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Compounds that block the function of connexin and pannexin protein channels have been suggested to be valuable therapeutics for a range of diseases. Some of these compounds are now in clinical trials, but for many of them, the literature is inconclusive about the molecular effect on the tissue, despite evidence of functional recovery. Blocking the different channel types has distinct physiological and pathological implications and this review describes current knowledge of connexin and pannexin protein channels, their function as channels and possible mechanisms of the channel block effect for the latest therapeutic compounds. We summarize the evidence implicating pannexins and connexins in disease, considering their homeostatic versus pathological roles, their contribution to excesive ATP release linked to disease onset and progression.
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Affiliation(s)
- Monica L Acosta
- School of Optometry and Vision Science; New Zealand National Eye Centre, University of Auckland; Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland; Brain Research New Zealand-Rangahau Roro Aotearoa, Auckland, New Zealand
| | - Mohd N Mat Nor
- School of Optometry and Vision Science, University of Auckland, Auckland, New Zealand; Faculty of Medicine, Universiti Sultan Zainal Abidin, Terengganu, Malaysia
| | - Cindy X Guo
- School of Optometry and Vision Science, University of Auckland, Auckland, New Zealand
| | - Odunayo O Mugisho
- Department of Ophthalmology, University of Auckland; Buchanan Ocular Therapeutics Unit, Department of Ophthalmology; New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Frazer P Coutinho
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand
| | - Ilva D Rupenthal
- Department of Ophthalmology, University of Auckland; Buchanan Ocular Therapeutics Unit, Department of Ophthalmology; New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Colin R Green
- Department of Ophthalmology; New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
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15
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Al Mamun A, Monalisa I, Tul Kubra K, Akter A, Akter J, Sarker T, Munir F, Wu Y, Jia C, Afrin Taniya M, Xiao J. Advances in immunotherapy for the treatment of spinal cord injury. Immunobiology 2020; 226:152033. [PMID: 33321368 DOI: 10.1016/j.imbio.2020.152033] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 10/19/2020] [Accepted: 11/18/2020] [Indexed: 12/11/2022]
Abstract
Spinal cord injury (SCI) is a leading cause of morbidity and disability in the world. Over the past few decades, the exact molecular mechanisms describing secondary, persistent injuries, as well as primary and transient injuries, have attracted massive attention to the clinicians and researchers. Recent investigations have distinctly shown the critical roles of innate and adaptive immune responses in regulating sterile neuroinflammation and functional outcomes after SCI. In past years, some promising advances in immunotherapeutic options have efficaciously been identified for the treatment of SCI. In our narrative review, we have mainly focused on the new therapeutic strategies such as the maturation and apoptosis of immune cells by several agents, mesenchymal stem cells (MSCs) as well as multi-factor combination therapy, which have recently provided novel ideas and prospects for the future treatment of SCI. This article also illustrates the latest progress in clarifying the potential roles of innate and adaptive immune responses in SCI, the progression and specification of prospective immunotherapy and outstanding issues in the area.
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Affiliation(s)
- Abdullah Al Mamun
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035 Zhejiang Province, China
| | - Ilma Monalisa
- Department of Pharmacy, Southeast University, Banani, Dhaka 1213, Bangladesh
| | - Khadija Tul Kubra
- Department of Pharmacy, University of Development Alternative, Dhaka 1209, Bangladesh
| | - Afroza Akter
- Department of Microbiology, Noakhali Science and Technology University, Noakhali 3814, Bangladesh
| | - Jaheda Akter
- Department of Pharmacy, International Islamic University Chittagong, Kumira, Chattogram-4318, Chittagong, Bangladesh
| | - Tamanna Sarker
- Department of Pharmacy, University of Asia Pacific, Dhaka 1205, Bangladesh
| | - Fahad Munir
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000 Zhejiang Province, China
| | - Yanqing Wu
- Institute of Life Sciences, Wenzhou University, Wenzhou, 325035 Zhejiang Province, China
| | - Chang Jia
- Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, 325027 Zhejiang Province, China
| | - Masuma Afrin Taniya
- Department of Life Sciences, School of Environment and Life Sciences, Independent University, Bangladesh, Dhaka 1229, Bangladesh
| | - Jian Xiao
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035 Zhejiang Province, China.
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16
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Huang SS, Cao S, Lu CE, Qin YB, Yang JP. Effects of nicorandil on p120 expression in the spinal cord and dorsal root ganglion of rats with chronic postsurgical pain. Mol Med Rep 2020; 22:4821-4827. [PMID: 33173987 PMCID: PMC7646919 DOI: 10.3892/mmr.2020.11546] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 08/21/2020] [Indexed: 01/25/2023] Open
Abstract
Chronic postsurgical pain (CPSP) has a high incidence, but the underlying mechanism is not well understood. Accumulating evidence has suggested that central sensitization is the main mechanism of pain. To study the role of p120 in CPSP, a skin/muscle incision and retraction (SMIR) model was established, and immunofluorescence staining and western blotting were performed to analyze the expression of p120 in the spinal cord and dorsal root ganglion (DRG). The results demonstrated that SMIR increased the expression of p120 in the DRG and the spinal cord compared with the naive group. Furthermore, it was demonstrated that p120 was mainly distributed in the glial fibrillary acidic protein-positive astrocytes in the spinal cord, and in the neurofilament 200-positive medium and large neurons in the DRG. Our previous studies have shown that adenosine triphosphate-sensitive potassium channel (KATP) agonists can reduce postoperative pain in rats. Therefore, the changes in p120 were observed in the DRG and spinal cord of rats following the intraperitoneal injection of nicorandil, a KATP agonist. It was demonstrated that nicorandil administration could relieve mechanical pain experienced following SMIR in rats, and decrease the expression of p120 in the DRG and spinal cord. The results revealed that p120 may contribute to the prophylactic analgesic effect of nicorandil, thus providing a novel insight into the mechanism of CPSP prevention.
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Affiliation(s)
- Sai-Sai Huang
- Department of Anesthesiology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215000, P.R. China
| | - Su Cao
- Department of Anesthesiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Cui E Lu
- Department of Anesthesiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Yi-Bin Qin
- Department of Anesthesiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Jian-Ping Yang
- Department of Anesthesiology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215000, P.R. China
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17
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Yang SH, Clemett CA, Brimble MA, O'Carroll SJ, Harris PWR. Synthesis and biological evaluation of S-lipidated lipopeptides of a connexin 43 channel inhibitory peptide. RSC Med Chem 2020; 11:1041-1047. [PMID: 33479696 DOI: 10.1039/d0md00172d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 06/18/2020] [Indexed: 01/08/2023] Open
Abstract
The synthesis and biological activity of 42 novel S-lipidated analogues of a connexin 43 channel inhibitory Peptide5 is described. Unmodified Peptide5 moderates hemichannels and gap junctions that are both implicated in the progression of neurological disease. Peptide5 was site-specifically modified with a cysteine residue, which then underwent thiol-ene mediated S-lipidation to afford S-lipidated Peptide5 analogues containing straight-chain, branched, or aromatic lipids. The modified peptides were assessed for their effect on hemichannel opening and the most promising candidates were evaluated in serum stability studies.
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Affiliation(s)
- Sung-Hyun Yang
- School of Chemical Sciences , The University of Auckland , 23 Symonds St , Auckland , New Zealand . .,School of Biological Sciences , The University of Auckland , 3a Symonds St, Private Bag 92019 , Auckland , New Zealand
| | - Connor A Clemett
- Department of Anatomy Medical Imaging , School of Medical Sciences , Faculty of Medical and Health Sciences, and Centre for Brain Research , University of Auckland , Private Bag 92019 , Auckland , New Zealand .
| | - Margaret A Brimble
- School of Chemical Sciences , The University of Auckland , 23 Symonds St , Auckland , New Zealand . .,School of Biological Sciences , The University of Auckland , 3a Symonds St, Private Bag 92019 , Auckland , New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery , The University of Auckland , 3a Symonds St , Auckland , New Zealand
| | - Simon J O'Carroll
- Department of Anatomy Medical Imaging , School of Medical Sciences , Faculty of Medical and Health Sciences, and Centre for Brain Research , University of Auckland , Private Bag 92019 , Auckland , New Zealand .
| | - Paul W R Harris
- School of Chemical Sciences , The University of Auckland , 23 Symonds St , Auckland , New Zealand . .,School of Biological Sciences , The University of Auckland , 3a Symonds St, Private Bag 92019 , Auckland , New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery , The University of Auckland , 3a Symonds St , Auckland , New Zealand
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18
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Mat Nor MN, Rupenthal ID, Green CR, Acosta ML. Connexin Hemichannel Block Using Orally Delivered Tonabersat Improves Outcomes in Animal Models of Retinal Disease. Neurotherapeutics 2020; 17:371-387. [PMID: 31637594 PMCID: PMC7007471 DOI: 10.1007/s13311-019-00786-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Increased Connexin43 hemichannel opening is associated with inflammasome pathway activation and inflammation in a range of pathologies including ocular disorders, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR). In this study, the effect on retinal function and morphology of clinically safe doses of orally delivered tonabersat, a small molecule connexin hemichannel blocker, was investigated in the light-damaged retina animal model of dry AMD and in a spontaneous rat model of DR. Clinical parameters (fundus imaging, optical coherence tomography (OCT), and electroretinography) and inflammatory markers (immunohistochemistry for Iba-1 microglial marker, astrocyte marker glial fibrillary acidic protein, and Connexin43 protein expression) were assessed. Tonabersat treatment reduced inflammation in the retina in parallel with preservation of retinal photoreceptor function when assessed up to 3 months post light damage in the dry AMD model. In the DR model, clinical signs, including the presence of aneurysms confirmed using Evans blue dye perfusion, were reduced after daily tonabersat treatment for 2 weeks. Inflammation was also reduced and retinal electrical function restored. Tonabersat regulates assembly of the inflammasome (NLRP3) through Connexin43 hemichannel block, with the potential to reduce inflammation, restore vascular integrity and improve anatomical along with some functional outcomes in retinal disease.
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Affiliation(s)
- Mohd Nasir Mat Nor
- School of Optometry and Vision Science and New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
- Faculty of Medicine, University of Sultan Zainal Abidin, Kuala Terengganu, Malaysia
| | - Ilva D Rupenthal
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, and New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
- Department of Ophthalmology and New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Colin R Green
- Department of Ophthalmology and New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Monica L Acosta
- School of Optometry and Vision Science and New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand.
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19
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The gap junction inhibitor INI-0602 attenuates mechanical allodynia and depression-like behaviors induced by spared nerve injury in rats. Neuroreport 2019; 30:369-377. [PMID: 30741784 DOI: 10.1097/wnr.0000000000001209] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Gap junctions (GJs) are novel molecular targets for pain therapeutics due to their pain-promoting function. INI-0602, a new GJ inhibitor, exerts a neuroprotective role, while its role in neuropathic pain is unclear. The objective was to investigate the analgesic role and mechanisms of INI-0602 in neuropathic pain induced by spared nerve injury (SNI), and whether INI-0602 attenuated pain-induced depression-like behaviors. Rats were randomly assigned to saline treatment groups (sham+NS and SNI+NS) or INI-0602 treatment groups (sham+INI-0602 and SNI+INI-0602). The von Frey test was used to assess pain behavior, and the sucrose preference test, the forced swimming test, and the tail suspension test were used to assess depression-like behaviors. Gap junction intercellular communication (GJIC) was measured by parachute assay. Western blots were used to determine the protein expression. In vitro, INI-0602 significantly suppressed GJIC by decreasing connexin43 and connexin32 expression. In vivo, INI-0602 significantly suppressed mechanical allodynia during initiation (7 days after SNI) and the maintenance phase (21 days after SNI) and simultaneously attenuated accompanying depression-like behaviors. Furthermore, INI-0602 markedly suppressed the activation of astrocytes and microglia on days 7 and 21 by reducing GJIC. Finally, INI-0602 reversed the changes in the brain-derived neurotrophic factor and Nr2b subunits of the N-methyl-D-aspartate receptor in SNI rats, suggesting that these effects of INI-0602 were related to its analgesic effect. Our findings demonstrated that blocking GJs with INI-0602 attenuated mechanical pain hypersensitivity and related depression-like behaviors in SNI rats by reducing glial activation.
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Brocardo L, Acosta LE, Piantanida AP, Rela L. Beneficial and Detrimental Remodeling of Glial Connexin and Pannexin Functions in Rodent Models of Nervous System Diseases. Front Cell Neurosci 2019; 13:491. [PMID: 31780897 PMCID: PMC6851021 DOI: 10.3389/fncel.2019.00491] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/17/2019] [Indexed: 01/30/2023] Open
Abstract
A variety of glial cell functions are supported by connexin and pannexin proteins. These functions include the modulation of synaptic gain, the control of excitability through regulation of the ion and neurotransmitter composition of the extracellular milieu and the promotion of neuronal survival. Connexins and pannexins support these functions through diverse molecular mechanisms, including channel and non-channel functions. The former comprise the formation of gap junction-mediated networks supported by connexin intercellular channels and the formation of pore-like membrane structures or hemichannels formed by both connexins and pannexins. Non-channel functions involve adhesion properties and the participation in signaling intracellular cascades. Pathological conditions of the nervous system such as ischemia, neurodegeneration, pathogen infection, trauma and tumors are characterized by distinctive remodeling of connexin expression and function. However, whether these changes can be interpreted as part of the pathogenesis, or as beneficial compensatory effects, remains under debate. Here we review the available evidence addressing this matter with a special emphasis in mouse models with selective manipulation of glial connexin and pannexin proteins in vivo. We postulate that the beneficial vs. detrimental effects of glial connexin remodeling in pathological conditions depend on the impact of remodeling on the different connexin and pannexin channel and non-channel functions, on the characteristics of the inflammatory environment and on the type of interaction among glial cells types.
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Affiliation(s)
- Lucila Brocardo
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Luis Ernesto Acosta
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ana Paula Piantanida
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Lorena Rela
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
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Mugisho OO, Rupenthal ID, Paquet-Durand F, Acosta ML, Green CR. Targeting connexin hemichannels to control the inflammasome: the correlation between connexin43 and NLRP3 expression in chronic eye disease. Expert Opin Ther Targets 2019; 23:855-863. [PMID: 31554417 DOI: 10.1080/14728222.2019.1673368] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Introduction: Chronic inflammatory diseases, including retinal diseases that are a major cause of vision loss, are associated with activation of the nucleotide-binding domain and leucine-rich repeat containing (NLR) protein-3 (NLRP3) inflammasome pathway. In chronic disease, the inflammasome becomes self-perpetuating, indicating a common pathway in such diseases irrespective of underlying etiology, and implying a shared solution is feasible. Connexin43 hemichannels correlate directly with NLRP3 inflammasome complex assembly (shown here in models of retinal disease). Connexin43 hemichannel-mediated ATP release is proposed to be the principal activator signal for inflammasome complex assembly in primary signal-sensitized cells. Connexin hemichannel block on its own is sufficient to inhibit the inflammasome pathway. Areas covered: We introduce chronic retinal disease, discuss available preclinical models and examine findings from these models regarding the targeting of connexin43 hemichannels and its effects on the inflammasome. Expert opinion: In over 25 animal disease models, connexin hemichannel regulation has shown therapeutic benefit, and one oral connexin hemichannel blocker, tonabersat (Xiflam), is Phase II ready with safety evidence in over 1000 patients. Regulating the connexin hemichannel provides a means to move quickly into clinical trials designed to ameliorate the progression of devastating chronic diseases of the eye, but also elsewhere in the body.
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Affiliation(s)
- Odunayo O Mugisho
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland , New Zealand
| | - Ilva D Rupenthal
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland , New Zealand
| | - Francois Paquet-Durand
- Cell Death Mechanisms Lab, Institute for Ophthalmic Research, University of Tübingen , Tübingen , Germany
| | - Monica L Acosta
- School of Optometry and Vision Science and the New Zealand National Eye Centre, University of Auckland , Auckland , New Zealand
| | - Colin R Green
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland , Auckland , New Zealand
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22
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Xing L, Yang T, Cui S, Chen G. Connexin Hemichannels in Astrocytes: Role in CNS Disorders. Front Mol Neurosci 2019; 12:23. [PMID: 30787868 PMCID: PMC6372977 DOI: 10.3389/fnmol.2019.00023] [Citation(s) in RCA: 122] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 01/21/2019] [Indexed: 12/19/2022] Open
Abstract
In the central nervous system (CNS), astrocytes form networks interconnected by gap junctions made from connexins of the subtypes Cx30 and Cx43. When unopposed by an adjoining hemichannel, astrocytic connexins can act as hemichannels to control the release of small molecules such as ATP and glutamate into the extracellular space. Accruing evidence indicates that astrocytic connexins are crucial for the coordination and maintenance of physiologic CNS activity. Here we provide an update on the role of astrocytic connexins in neurodegenerative disorders, glioma, and ischemia. In addition, we address the regulation of Cx43 in chronic pain.
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Affiliation(s)
- LingYan Xing
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Tuo Yang
- Department of Hand Surgery, China-Japan Union Hospital of Jilin University, Changchun, China
| | - ShuSen Cui
- Department of Hand Surgery, China-Japan Union Hospital of Jilin University, Changchun, China
| | - Gang Chen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China.,Department of Anesthesiology, Affiliated Hospital of Nantong University, Nantong, China
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The Role of Connexin-43 in the Inflammatory Process: A New Potential Therapy to Influence Keratitis. J Ophthalmol 2019; 2019:9312827. [PMID: 30805212 PMCID: PMC6360563 DOI: 10.1155/2019/9312827] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 11/12/2018] [Accepted: 11/19/2018] [Indexed: 12/22/2022] Open
Abstract
The studies outlined in this review highlight the relationship between inflammatory signaling molecules and connexin-43 (Cx43). Gap junction (GJ) channels and hemichannels (HCs) participate in the metabolic activity between intra- and extracellular space. Some ions and small molecules are exchanged from cell to cell or cell to extracellular space to affect the process of inflammation via GJ. We analyzed the effects of signaling molecules, such as innate immunity messengers, transcription factors, LPS, cytokine, inflammatory chemokines, and MMPs, on Cx43 expression during the inflammatory process. At the same time, we found that these signaling molecules play a critical role in the pathogenesis of keratitis. Thus, we assessed the function of Cx43 during inflammatory corneal disease. Corneal healing plays an essential role in the late stage of keratitis. We found that Cx43 is involved in wound healing. Studies have shown that the decrease of Cx43 can decrease the time of healing. We also report several Cx43 mimic peptides which can inhibit the activity of Cx43 Hc to mediate the releasing of adenosine triphosphate (ATP), which may in turn influence the inflammatory process.
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24
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Connexin43 hemichannel block protects against the development of diabetic retinopathy signs in a mouse model of the disease. J Mol Med (Berl) 2018; 97:215-229. [DOI: 10.1007/s00109-018-1727-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/25/2018] [Accepted: 11/30/2018] [Indexed: 12/22/2022]
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25
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Therapeutic Targeting of Connexin Channels: New Views and Challenges. Trends Mol Med 2018; 24:1036-1053. [PMID: 30424929 DOI: 10.1016/j.molmed.2018.10.005] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 10/09/2018] [Accepted: 10/11/2018] [Indexed: 12/22/2022]
Abstract
Connexins, in particular connexin 43 (Cx43), function as gap junction channels (GJCs) and hemichannels (HCs). Only recently, specific tools have been developed to study their pleiotropic functions. Based on various protein interaction sites, distinct connexin-mimetic peptides have been established that enable discrimination between the function of HCs and GJCs. Although the precise mechanism of action of most of these peptides is still a matter of debate, an increasing number of studies report on important effects of those compounds in disease models. In this review, we summarize the structure, life cycle, and the most important physiological and pathological functions of both connexin GJCs and HCs. We provide a critical overview on the use of connexin-targeting peptides, in particular targeting Cx43, with a special focus on the remaining questions and hurdles to be taken in the research field of connexin channels.
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26
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Lu X, Perera TH, Aria AB, Callahan LAS. Polyethylene glycol in spinal cord injury repair: a critical review. J Exp Pharmacol 2018; 10:37-49. [PMID: 30100766 PMCID: PMC6067622 DOI: 10.2147/jep.s148944] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Polyethylene glycol (PEG) is a synthetic biocompatible polymer with many useful properties for developing therapeutics to treat spinal cord injury. Direct application of PEG as a fusogen to the injury site can repair cell membranes, mitigate oxidative stress, and promote axonal regeneration to restore motor function. PEG can be covalently or noncovalently conjugated to proteins, peptides, and nanoparticles to limit their clearance by the reticuloendothelial system, reduce their immunogenicity, and facilitate crossing the blood-brain barrier. Cross-linking PEG produces hydrogels that can act as delivery vehicles for bioactive molecules including growth factors and cells such as bone marrow stromal cells, which can modulate the inflammatory response and support neural tissue regeneration. PEG hydrogels can be cross-linked in vitro or delivered as an injectable formulation that can gel in situ at the site of injury. Chemical and mechanical properties of PEG hydrogels are tunable and must be optimized for creating the most favorable delivery environment. Peptides mimicking extracellular matrix protein such as laminin and n-cadherin can be incorporated into PEG hydrogels to promote neural differentiation and axonal extensions. Different hydrogel cross-linking densities and stiffness will also affect the differentiation process. PEG hydrogels with a gradient of peptide concentrations or Young's modulus have been developed to systematically study these factors. This review will describe these and other recent advancements of PEG in the field of spinal cord injury in greater detail.
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Affiliation(s)
- Xi Lu
- Department of Neurosurgery, Center for Stem Cells and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA,
| | - T Hiran Perera
- Department of Neurosurgery, Center for Stem Cells and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA,
| | - Alexander B Aria
- Department of Neurosurgery, Center for Stem Cells and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA,
| | - Laura A Smith Callahan
- Department of Neurosurgery, Center for Stem Cells and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA,
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27
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Mat Nor N, Guo CX, Rupenthal ID, Chen YS, Green CR, Acosta ML. Sustained Connexin43 Mimetic Peptide Release From Loaded Nanoparticles Reduces Retinal and Choroidal Photodamage. Invest Ophthalmol Vis Sci 2018; 59:3682-3693. [PMID: 30029255 DOI: 10.1167/iovs.17-22829] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Purpose To evaluate the long-term effect on inflammation and inflammasome activation of intravitreally delivered connexin43 mimetic peptide (Cx43MP) in saline or incorporated within nanoparticles (NPs) for the treatment of the light-damaged rat eye. Methods Light-induced damage to the retina was created by exposure of adult albino Sprague-Dawley rats to intense light for 24 hours. A single dose of Cx43MP, Cx43MP-NPs, or saline was injected intravitreally at 2 hours after onset of light damage. Fluorescein isothiocyanate (FITC)-labelled Cx43MP-NPs were intravitreally injected to confirm delivery into the retina. Electroretinogram (ERG) recordings were performed at 24 hours, 1 week, and 2 weeks post cessation of light damage. The retinal and choroidal layers were analyzed in vivo using optical coherence tomography (OCT) and immunohistochemistry was performed on harvested tissues using glial fibrillary acidic protein (GFAP), leukocyte common antigen (CD45), and Cx43 antibodies. Results FITC was visualized 30 minutes after injection in the ganglion cell layer and in the choroid. Cx43MP and Cx43MP-NP treatments improved a-wave and b-wave function of the ERG compared with saline-injected eyes at 1 week and 2 weeks post treatment, and prevented photoreceptor loss by 2 weeks post treatment. Inflammation was also reduced and this was in parallel with downregulation of Cx43 expression. Conclusions The slow release of Cx43MP incorporated into NPs is more effective at treating retinal injury than a single dose of native Cx43MP in solution by reducing inflammation and maintaining both retinal structure and function. This NP preparation has clinical relevance as it reduces possible ocular complications associated with repeated intravitreal injections.
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Affiliation(s)
- Nasir Mat Nor
- School of Optometry and Vision Science, University of Auckland, Auckland, New Zealand.,Faculty of Medicine, University of Sultan Zainal Abidin, Kuala Terengganu, Malaysia.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Cindy X Guo
- School of Optometry and Vision Science, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Ilva D Rupenthal
- New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand.,Department of Ophthalmology, University of Auckland, Auckland, New Zealand.,Buchanan Ocular Therapeutics Unit, University of Auckland, Auckland, New Zealand
| | - Ying-Shan Chen
- New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand.,Department of Ophthalmology, University of Auckland, Auckland, New Zealand.,Buchanan Ocular Therapeutics Unit, University of Auckland, Auckland, New Zealand
| | - Colin R Green
- New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand.,Department of Ophthalmology, University of Auckland, Auckland, New Zealand
| | - Monica L Acosta
- School of Optometry and Vision Science, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
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Rhett JM, Yeh ES. The Potential for Connexin Hemichannels to Drive Breast Cancer Progression through Regulation of the Inflammatory Response. Int J Mol Sci 2018; 19:ijms19041043. [PMID: 29601539 PMCID: PMC5979453 DOI: 10.3390/ijms19041043] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 03/27/2018] [Accepted: 03/28/2018] [Indexed: 12/12/2022] Open
Abstract
Over the past few decades, connexin hemichannels have become recognized as major players in modulating the inflammatory response. Chronic inflammation is documented to promote tumorigenesis and is a critical component of tumor progression. Furthermore, inflammation is strongly linked to angiogenesis, immunotolerance, invasiveness, metastasis, and resistance in breast cancers. In this review, the literature on the role of connexin hemichannels in inflammation is summarized, and the potential role for hemichannel-mediated inflammation in driving breast cancer progression is discussed. Lastly, the potential for connexin-based therapeutics to modulate the inflammatory component of the tumor microenvironment as an avenue for the treatment of breast cancer is also discussed.
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Affiliation(s)
- J Matthew Rhett
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, Charleston, SC 29412, USA.
| | - Elizabeth S Yeh
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, Charleston, SC 29412, USA.
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30
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Mugisho OO, Green CR, Kho DT, Zhang J, Graham ES, Acosta ML, Rupenthal ID. The inflammasome pathway is amplified and perpetuated in an autocrine manner through connexin43 hemichannel mediated ATP release. Biochim Biophys Acta Gen Subj 2018; 1862:385-393. [DOI: 10.1016/j.bbagen.2017.11.015] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/30/2017] [Accepted: 11/16/2017] [Indexed: 12/20/2022]
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31
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Ziaei M, Greene C, Green CR. Wound healing in the eye: Therapeutic prospects. Adv Drug Deliv Rev 2018; 126:162-176. [PMID: 29355667 DOI: 10.1016/j.addr.2018.01.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 10/06/2017] [Accepted: 01/10/2018] [Indexed: 02/07/2023]
Abstract
In order to maintain a smooth optical surface the corneal epithelium has to continuously renew itself so as to maintain its function as a barrier to fluctuating external surroundings and various environmental insults. After trauma, the cornea typically re-epithelializes promptly thereby minimizing the risk of infection, opacification or perforation. A persistent epithelial defect (PED) is usually referred to as a non-healing epithelial lesion after approximately two weeks of treatment with standard therapies to no avail. They occur following exposure to toxic agents, mechanical injury, and ocular surface infections and are associated with significant clinical morbidity in patients, resulting in discomfort or visual loss. In the case of deeper corneal injury and corneal pathology the wound healing cascade can also extend to the corneal stroma, the layer below the epithelium. Although significant progress has been made in recent years, pharmaco-therapeutic agents that promote corneal healing remain limited. This article serves as a review of current standard therapies, recently introduced alternative therapies gaining in popularity, and a look into the newest developments into ocular wound healing.
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Mugisho OO, Green CR, Zhang J, Binz N, Acosta ML, Rakoczy E, Rupenthal ID. Immunohistochemical Characterization of Connexin43 Expression in a Mouse Model of Diabetic Retinopathy and in Human Donor Retinas. Int J Mol Sci 2017; 18:ijms18122567. [PMID: 29186067 PMCID: PMC5751170 DOI: 10.3390/ijms18122567] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 11/21/2017] [Accepted: 11/24/2017] [Indexed: 12/25/2022] Open
Abstract
Diabetic retinopathy (DR) develops due to hyperglycemia and inflammation-induced vascular disruptions in the retina with connexin43 expression patterns in the disease still debated. Here, the effects of hyperglycemia and inflammation on connexin43 expression in vitro in a mouse model of DR and in human donor tissues were evaluated. Primary human retinal microvascular endothelial cells (hRMECs) were exposed to high glucose (HG; 25 mM) or pro-inflammatory cytokines IL-1β and TNF-α (10 ng/mL each) or both before assessing connexin43 expression. Additionally, connexin43, glial fibrillary acidic protein (GFAP), and plasmalemma vesicular associated protein (PLVAP) were labeled in wild-type (C57BL/6), Akita (diabetic), and Akimba (DR) mouse retinas. Finally, connexin43 and GFAP expression in donor retinas with confirmed DR was compared to age-matched controls. Co-application of HG and cytokines increased connexin43 expression in hRMECs in line with results seen in mice, with no significant difference in connexin43 or GFAP expression in Akita but higher expression in Akimba compared to wild-type mice. On PLVAP-positive vessels, connexin43 was higher in Akimba but unchanged in Akita compared to wild-type mice. Connexin43 expression appeared higher in donor retinas with confirmed DR compared to age-matched controls, similar to the distribution seen in Akimba mice and correlating with the in vitro results. Although connexin43 expression seems reduced in diabetes, hyperglycemia and inflammation present in the pathology of DR seem to increase connexin43 expression, suggesting a causal role of connexin43 channels in the disease progression.
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Affiliation(s)
- Odunayo O Mugisho
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland 1142, New Zealand.
- School of Optometry and Vision Science, New Zealand National Eye Centre, University of Auckland, Auckland 1142, New Zealand.
| | - Colin R Green
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland 1142, New Zealand.
| | - Jie Zhang
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland 1142, New Zealand.
| | - Nicolette Binz
- Centre for Ophthalmology and Visual Science, University of Western Australia, Perth 6009, Western Australia, Australia.
| | - Monica L Acosta
- School of Optometry and Vision Science, New Zealand National Eye Centre, University of Auckland, Auckland 1142, New Zealand.
| | - Elizabeth Rakoczy
- Centre for Ophthalmology and Visual Science, University of Western Australia, Perth 6009, Western Australia, Australia.
| | - Ilva D Rupenthal
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland 1142, New Zealand.
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Attenuation of mechanical pain hypersensitivity by treatment with Peptide5, a connexin-43 mimetic peptide, involves inhibition of NLRP3 inflammasome in nerve-injured mice. Exp Neurol 2017; 300:1-12. [PMID: 29055716 DOI: 10.1016/j.expneurol.2017.10.016] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 09/22/2017] [Accepted: 10/17/2017] [Indexed: 02/07/2023]
Abstract
Connexin43 (Cx43) hemichannels in spinal cord astrocytes are implicated in the maintenance of neuropathic pain following peripheral nerve injury. Peptide5 is a Cx43 mimetic peptide that blocks hemichannels. In this study, we investigated the effects of spinal delivery of Peptide5 on mechanical pain hypersensitivity in two mouse models of neuropathic pain, peripheral nerve injury and chemotherapy-induced peripheral neuropathy (CIPN). We demonstrated that 10days following a chronic constriction injury (CCI) of the sciatic nerve, Cx43 expression, co-localised predominantly with astrocytes, was increased in the ipsilateral L3-L5 lumbar spinal cord. An intrathecal injection of Peptide5 into nerve-injured mice, on day 10 when pain was well-established, caused significant improvement in mechanical pain hypersensitivity 8h after injection. Peptide5 treatment resulted in significantly reduced Cx43, and microglial and astrocyte activity in the dorsal horn of the spinal cord, as compared to control saline-treated CCI mice. Further in vitro investigations on primary astrocyte cultures showed that 1h pre-treatment with Peptide5 significantly reduced adenosine triphosphate (ATP) release in response to extracellular calcium depletion. Since ATP is a known activator of the NOD-like receptor protein 3 (NLRP3) inflammasome complex, a key mediator of neuroinflammation, we examined the effects of Peptide5 treatment on NLRP3 inflammasome expression. We found that NLRP3, its adaptor apoptosis-associated spec-like protein (ASC) and caspase-1 protein were increased in the ipsilateral spinal cord of CCI mice and reduced to naïve levels following Peptide5 treatment. In the models of oxaliplatin- and paclitaxel-induced peripheral neuropathy, treatment with Peptide5 had no effect on mechanical pain hypersensitivity. Interestingly, in these CIPN models, although spinal Cx43 expression was significantly increased at day 13 following chemotherapy, NLRP3 expression was not altered. These results suggest that the analgesic effect of Peptide5 is specifically achieved by reducing NLRP3 expression. Together, our findings demonstrate that blocking Cx43 hemichannels with Peptide5 after nerve injury attenuates mechanical pain hypersensitivity by specifically targeting the NLRP3 inflammasome in the spinal cord.
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Leybaert L, Lampe PD, Dhein S, Kwak BR, Ferdinandy P, Beyer EC, Laird DW, Naus CC, Green CR, Schulz R. Connexins in Cardiovascular and Neurovascular Health and Disease: Pharmacological Implications. Pharmacol Rev 2017; 69:396-478. [PMID: 28931622 PMCID: PMC5612248 DOI: 10.1124/pr.115.012062] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Connexins are ubiquitous channel forming proteins that assemble as plasma membrane hemichannels and as intercellular gap junction channels that directly connect cells. In the heart, gap junction channels electrically connect myocytes and specialized conductive tissues to coordinate the atrial and ventricular contraction/relaxation cycles and pump function. In blood vessels, these channels facilitate long-distance endothelial cell communication, synchronize smooth muscle cell contraction, and support endothelial-smooth muscle cell communication. In the central nervous system they form cellular syncytia and coordinate neural function. Gap junction channels are normally open and hemichannels are normally closed, but pathologic conditions may restrict gap junction communication and promote hemichannel opening, thereby disturbing a delicate cellular communication balance. Until recently, most connexin-targeting agents exhibited little specificity and several off-target effects. Recent work with peptide-based approaches has demonstrated improved specificity and opened avenues for a more rational approach toward independently modulating the function of gap junctions and hemichannels. We here review the role of connexins and their channels in cardiovascular and neurovascular health and disease, focusing on crucial regulatory aspects and identification of potential targets to modify their function. We conclude that peptide-based investigations have raised several new opportunities for interfering with connexins and their channels that may soon allow preservation of gap junction communication, inhibition of hemichannel opening, and mitigation of inflammatory signaling.
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Affiliation(s)
- Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Paul D Lampe
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Stefan Dhein
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Brenda R Kwak
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Peter Ferdinandy
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Eric C Beyer
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Dale W Laird
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Christian C Naus
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Colin R Green
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Rainer Schulz
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
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35
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Kim Y, Griffin JM, Nor MNM, Zhang J, Freestone PS, Danesh-Meyer HV, Rupenthal ID, Acosta M, Nicholson LFB, O'Carroll SJ, Green CR. Tonabersat Prevents Inflammatory Damage in the Central Nervous System by Blocking Connexin43 Hemichannels. Neurotherapeutics 2017; 14:1148-1165. [PMID: 28560708 PMCID: PMC5722754 DOI: 10.1007/s13311-017-0536-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The cis benzopyran compound tonabersat (SB-220453) has previously been reported to inhibit connexin26 expression in the brain by attenuating the p38-mitogen-activated protein kinase pathway. We show here that tonabersat directly inhibits connexin43 hemichannel opening. Connexin43 hemichannels have been called "pathological pores" based upon their role in secondary lesion spread, edema, inflammation, and neuronal loss following central nervous system injuries, as well as in chronic inflammatory disease. Both connexin43 hemichannels and pannexin channels released adenosine triphosphate (ATP) during ischemia in an in vitro ischemia model, but only connexin43 hemichannels contributed to ATP release during reperfusion. Tonabersat inhibited connexin43 hemichannel-mediated ATP release during both ischemia and reperfusion phases, with direct channel block confirmed using electrophysiology. Tonabersat also reduced connexin43 gap junction coupling in vitro, but only at higher concentrations, with junctional plaques internalized and degraded via the lysosomal pathway. Systemic delivery of tonabersat in a rat bright-light retinal damage model (a model for dry age-related macular degeneration) resulted in significantly improved functional outcomes assessed using electroretinography. Tonabersat also prevented thinning of the retina, especially the outer nuclear layer and choroid, assessed using optical coherence tomography. We conclude that tonabersat, already given orally to over 1000 humans in clinical trials (as a potential treatment for, and prophylactic treatment of, migraine because it was thought to inhibit cortical spreading depression), is a connexin hemichannel inhibitor and may have the potential to be a novel treatment of central nervous system injury and chronic neuroinflammatory disease.
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Affiliation(s)
- Yeri Kim
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
- New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Jarred M Griffin
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Mohd N Mat Nor
- New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
- School of Optometry and Vision Science, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
- Faculty of Medicine, University Sultan Zainal Abidin, Kuala Terengganu, Malaysia
| | - Jie Zhang
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
- New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Peter S Freestone
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Helen V Danesh-Meyer
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
- New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Ilva D Rupenthal
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
- New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
- Buchanan Ocular Therapeutics Unit, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Monica Acosta
- New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
- School of Optometry and Vision Science, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Louise F B Nicholson
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Simon J O'Carroll
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Colin R Green
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand.
- New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand.
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36
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Mao Y, Nguyen T, Tonkin RS, Lees JG, Warren C, O'Carroll SJ, Nicholson LFB, Green CR, Moalem-Taylor G, Gorrie CA. Characterisation of Peptide5 systemic administration for treating traumatic spinal cord injured rats. Exp Brain Res 2017; 235:3033-3048. [PMID: 28725925 DOI: 10.1007/s00221-017-5023-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 07/03/2017] [Indexed: 11/27/2022]
Abstract
Systemic administration of a Connexin43 mimetic peptide, Peptide5, has been shown to reduce secondary tissue damage and improve functional recovery after spinal cord injury (SCI). This study investigated safety measures and potential off-target effects of Peptide5 systemic administration. Rats were subjected to a mild contusion SCI using the New York University impactor. One cohort was injected intraperitoneally with a single dose of fluorescently labelled Peptide5 and euthanised at 2 or 4 h post-injury for peptide distribution analysis. A second cohort received intraperitoneal injections of Peptide5 or a scrambled peptide and was culled at 8 or 24 h post-injury for the analysis of connexin proteins and systemic cytokine profile. We found that Peptide5 did not cross the blood-spinal cord barrier in control animals, but reached the lesion area in the spinal cord-injured animals without entering non-injured tissue. There was no evidence that the systemic administration of Peptide5 modulates Connexin43 protein expression or hemichannel closure in the heart and lung tissue of SCI animals. The expression levels of other major connexin proteins including Connexin30 in astrocytes, Connexin36 in neurons and Connexin47 in oligodendrocytes were also unaltered by systemic delivery of Peptide5 in either the injured or non-injured spinal cords. In addition, systemic delivery of Peptide5 had no significant effect on the plasma levels of cytokines, chemokines or growth factors. These data indicate that the systemic delivery of Peptide5 is unlikely to cause any off-target or adverse effects and may thus be a safe treatment option for traumatic SCI.
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Affiliation(s)
- Yilin Mao
- Neural Injury Research Unit, School of Life Sciences, Faculty of Science, University of Technology Sydney, P.O. Box 123, Broadway, NSW, 2007, Australia
| | - Tara Nguyen
- Neural Injury Research Unit, School of Life Sciences, Faculty of Science, University of Technology Sydney, P.O. Box 123, Broadway, NSW, 2007, Australia
| | - Ryan S Tonkin
- Neuropathic Pain Research Group, Translational Neuroscience Facility, School of Medical Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Justin G Lees
- Neuropathic Pain Research Group, Translational Neuroscience Facility, School of Medical Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Caitlyn Warren
- Neural Injury Research Unit, School of Life Sciences, Faculty of Science, University of Technology Sydney, P.O. Box 123, Broadway, NSW, 2007, Australia
| | - Simon J O'Carroll
- Department of Anatomy and Medical Imaging and The Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Louise F B Nicholson
- Department of Anatomy and Medical Imaging and The Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Colin R Green
- Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Gila Moalem-Taylor
- Neuropathic Pain Research Group, Translational Neuroscience Facility, School of Medical Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Catherine A Gorrie
- Neural Injury Research Unit, School of Life Sciences, Faculty of Science, University of Technology Sydney, P.O. Box 123, Broadway, NSW, 2007, Australia.
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37
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Yi C, Ezan P, Fernández P, Schmitt J, Sáez JC, Giaume C, Koulakoff A. Inhibition of glial hemichannels by boldine treatment reduces neuronal suffering in a murine model of Alzheimer's disease. Glia 2017; 65:1607-1625. [PMID: 28703353 DOI: 10.1002/glia.23182] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 05/04/2017] [Accepted: 05/30/2017] [Indexed: 01/06/2023]
Abstract
The contribution of reactive gliosis to the pathological phenotype of Alzheimer's disease (AD) opened the way for therapeutic strategies targeting glial cells instead of neurons. In such context, connexin hemichannels were proposed recently as potential targets since neuronal suffering is alleviated when connexin expression is genetically suppressed in astrocytes of a murine model of AD. Here, we show that boldine, an alkaloid from the boldo tree, inhibited hemichannel activity in astrocytes and microglia without affecting gap junctional communication in culture and acute hippocampal slices. Long-term oral administration of boldine in AD mice prevented the increase in glial hemichannel activity, astrocytic Ca2+ signal, ATP and glutamate release and alleviated hippocampal neuronal suffering. These findings highlight the important pathological role of hemichannels in AD mice. The neuroprotective effect of boldine treatment might provide the basis for future pharmacological strategies that target glial hemichannels to reduce neuronal damage in neurodegenerative diseases.
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Affiliation(s)
- Chenju Yi
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, 75005, France
| | - Pascal Ezan
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, 75005, France
| | - Paola Fernández
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro Interdisciplinario de Neurociencias de Valparaíso, Valparaíso, Chile
| | - Julien Schmitt
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Neurosciences Paris Seine, Institut de Biologie Paris Seine (NPS-IBPS), Cerebellum Navigation and Memory team (CeZaMe), Paris, 75005, France
| | - Juan C Sáez
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro Interdisciplinario de Neurociencias de Valparaíso, Valparaíso, Chile
| | - Christian Giaume
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, 75005, France
| | - Annette Koulakoff
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, 75005, France
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