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Han N, Liu Y, Li X, Du J, Guo L, Liu Y. Reuterin isolated from the probiotic Lactobacillus reuteri promotes periodontal tissue regeneration by inhibiting Cx43-mediated the intercellular transmission of endoplasmic reticulum stress. J Periodontal Res 2024; 59:552-564. [PMID: 38193526 DOI: 10.1111/jre.13233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 12/06/2023] [Accepted: 12/20/2023] [Indexed: 01/10/2024]
Abstract
OBJECTIVE The present study aimed to evaluate the effects of reuterin, a bioactive isolated from the probiotic Lactobacillus reuteri (L. reuteri) on periodontal tissue regeneration, and provide a new strategy for periodontitis treatment in the future. BACKGROUND Data discussing the present state of the field: Probiotics are essential for maintaining oral microecological balance. Our previous study confirmed that probiotic L. reuteri extracts could rescue the function of mesenchymal stem cells (MSCs) and promote soft tissue wound healing by neutralizing inflammatory Porphyromonas gingivalis-LPS. Periodontitis is a chronic inflammatory disease caused by bacteria seriously leading to tooth loss. In this study, we isolated and purified reuterin from an extract of L. reuteri to characterize from the extracts of L. reuteri to characterize its role in promoting periodontal tissue regeneration and controlling inflammation in periodontitis. METHODS Chromatographic analysis was used to isolate and purify reuterin from an extract of L. reuteri, and HNMR was used to characterize its structure. The inflammatory cytokine TNFα was used to simulate the inflammatory environment. Periodontal ligament stem cells (PDLSCs) were treated with TNFα and reuterin after which their effects were characterized using scratch wound cell migration assays to determine the concentration of reuterin, an experimental periodontitis model in rats was used to investigate the function of reuterin in periodontal regeneration and inflammation control in vivo. Real-time PCR, dye transfer experiments, image analysis, alkaline phosphatase activity, Alizarin red staining, cell proliferation, RNA-sequencing and Western Blot assays were used to detect the function of PDLSCs. RESULTS In vivo, local injection of reuterin promoted periodontal tissue regeneration of experimental periodontitis in rats and reduced local inflammatory response. Moreover, we found that TNFα stimulation caused endoplasmic reticulum (ER) stress in PDLSCs, which resulted in decreased osteogenic differentiation. Treatment with reuterin inhibited the ER stress state of PDLSCs caused by the inflammatory environment and restored the osteogenic differentiation and cell proliferation functions of inflammatory PDLSCs. Mechanistically, we found that reuterin restored the functions of inflammatory PDLSCs by inhibiting the intercellular transmission of ER stress mediated by Cx43 in inflammatory PDLSCs and regulated osteogenic differentiation capacity. CONCLUSION Our findings identified reuterin isolated from extracts of the probiotic L. reuteri, which improves tissue regeneration and controls inflammation, thus providing a new therapeutic method for treating periodontitis.
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Affiliation(s)
- Nannan Han
- Laboratory of Tissue Regeneration and Immunology and Department of Periodontics, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, School of Stomatology, Capital Medical University, Beijing, P. R. China
- Immunology Research Center for Oral and Systemic Health, Beijing Friendship Hospital, Capital Medical University, Beijing, P. R. China
| | - Yitong Liu
- Laboratory of Tissue Regeneration and Immunology and Department of Periodontics, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, School of Stomatology, Capital Medical University, Beijing, P. R. China
- Immunology Research Center for Oral and Systemic Health, Beijing Friendship Hospital, Capital Medical University, Beijing, P. R. China
| | - Xiaoyan Li
- Laboratory of Tissue Regeneration and Immunology and Department of Periodontics, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, School of Stomatology, Capital Medical University, Beijing, P. R. China
- Immunology Research Center for Oral and Systemic Health, Beijing Friendship Hospital, Capital Medical University, Beijing, P. R. China
| | - Juan Du
- Laboratory of Tissue Regeneration and Immunology and Department of Periodontics, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, School of Stomatology, Capital Medical University, Beijing, P. R. China
- Immunology Research Center for Oral and Systemic Health, Beijing Friendship Hospital, Capital Medical University, Beijing, P. R. China
| | - Lijia Guo
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, P. R. China
| | - Yi Liu
- Laboratory of Tissue Regeneration and Immunology and Department of Periodontics, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, School of Stomatology, Capital Medical University, Beijing, P. R. China
- Immunology Research Center for Oral and Systemic Health, Beijing Friendship Hospital, Capital Medical University, Beijing, P. R. China
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Mavridis T, Mavridi A, Karampela E, Galanos A, Gkiokas G, Iacovidou N, Xanthos T. Sovateltide (ILR-1620) Improves Motor Function and Reduces Hyperalgesia in a Rat Model of Spinal Cord Injury. Neurocrit Care 2024:10.1007/s12028-024-01950-2. [PMID: 38443708 DOI: 10.1007/s12028-024-01950-2] [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: 10/23/2023] [Accepted: 01/26/2024] [Indexed: 03/07/2024]
Abstract
BACKGROUND Spinal cord injury (SCI) presents a major global health challenge, with rising incidence rates and substantial disability. Although progress has been made in understanding SCI's pathophysiology and early management, there is still a lack of effective treatments to mitigate long-term consequences. This study investigates the potential of sovateltide, a selective endothelin B receptor agonist, in improving clinical outcomes in an acute SCI rat model. METHODS Thirty male Sprague-Dawley rats underwent sham surgery (group A) or SCI and treated with vehicle (group B) or sovateltide (group C). Clinical tests, including Basso, Beattie, and Bresnahan scoring, inclined plane, and allodynia testing with von Frey hair, were performed at various time points. Statistical analyses assessed treatment effects. RESULTS Sovateltide administration significantly improved motor function, reducing neurological deficits and enhancing locomotor recovery compared with vehicle-treated rats, starting from day 7 post injury. Additionally, the allodynic threshold improved, suggesting antinociceptive properties. Notably, the sovateltide group demonstrated sustained recovery, and even reached preinjury performance levels, whereas the vehicle group plateaued. CONCLUSIONS This study suggests that sovateltide may offer neuroprotective effects, enhancing neurogenesis and angiogenesis. Furthermore, it may possess anti-inflammatory and antinociceptive properties. Future clinical trials are needed to validate these findings, but sovateltide shows promise as a potential therapeutic strategy to improve functional outcomes in SCI. Sovateltide, an endothelin B receptor agonist, exhibits neuroprotective properties, enhancing motor recovery and ameliorating hyperalgesia in a rat SCI model. These findings could pave the way for innovative pharmacological interventions for SCI in clinical settings.
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Affiliation(s)
- Theodoros Mavridis
- First Department of Neurology, Eginition Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
- Department of Neurology, Tallaght University Hospital (TUH)/The Adelaide and Meath Hospital, Dublin, Incorporating the National Children's Hospital (AMNCH), Dublin, Ireland.
| | - Artemis Mavridi
- First Department of Pediatrics, Medical School, Aghia Sophia Children's Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | | | - Antonis Galanos
- Laboratory for Research of the Musculoskeletal System, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - George Gkiokas
- Second Department of Surgery, Aretaieion University Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Nicoletta Iacovidou
- Department of Neonatology, Aretaieio Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Theodoros Xanthos
- School of Health and Caring Sciences, University of West Attica, Athens, Greece
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Kwek MSY, Thangaveloo M, Madden LE, Phillips ARJ, Becker DL. Targeting Cx43 to Reduce the Severity of Pressure Ulcer Progression. Cells 2023; 12:2856. [PMID: 38132176 PMCID: PMC10741864 DOI: 10.3390/cells12242856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/07/2023] [Accepted: 12/15/2023] [Indexed: 12/23/2023] Open
Abstract
In the skin, repeated incidents of ischemia followed by reperfusion can result in the breakdown of the skin and the formation of a pressure ulcer. Here we gently applied paired magnets to the backs of mice to cause ischemia for 1.5 h and then removed them to allow reperfusion. The sterile inflammatory response generated within 4 h causes a stage 1 pressure ulcer with an elevation of the gap junction protein Cx43 in the epidermis. If this process is repeated the insult will result in a more severe stage 2 pressure ulcer with a breakdown of the epidermis 2-3 days later. After a single pinch, the elevation of Cx43 in the epidermis is associated with the inflammatory response with an increased number of neutrophils, HMGB1 (marker of necrosis) and RIP3 (responsible for necroptosis). Delivering Cx43 specific antisense oligonucleotides sub-dermally after a single insult, was able to significantly reduce the elevation of epidermal Cx43 protein expression and reduce the number of neutrophils and prevent the elevation of HMGB1 and RIP3. In a double pinch model, the Cx43 antisense treatment was able to reduce the level of inflammation, necroptosis, and the extent of tissue damage and progression to an open wound. This approach may be useful in reducing the progression of stage 1 pressure ulcers to stage 2.
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Affiliation(s)
- Milton Sheng Yi Kwek
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Clinical Sciences Building, 11, Mandalay Road, Singapore 308232, Singapore (M.T.); (L.E.M.)
- Skin Research Institute Singapore, Clinical Sciences Building, 11, Mandalay Road, Singapore 308232, Singapore
| | - Moogaambikai Thangaveloo
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Clinical Sciences Building, 11, Mandalay Road, Singapore 308232, Singapore (M.T.); (L.E.M.)
- Skin Research Institute Singapore, Clinical Sciences Building, 11, Mandalay Road, Singapore 308232, Singapore
| | - Leigh E. Madden
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Clinical Sciences Building, 11, Mandalay Road, Singapore 308232, Singapore (M.T.); (L.E.M.)
- Skin Research Institute Singapore, Clinical Sciences Building, 11, Mandalay Road, Singapore 308232, Singapore
| | | | - David L. Becker
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Clinical Sciences Building, 11, Mandalay Road, Singapore 308232, Singapore (M.T.); (L.E.M.)
- Skin Research Institute Singapore, Clinical Sciences Building, 11, Mandalay Road, Singapore 308232, Singapore
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Eitelmann S, Everaerts K, Petersilie L, Rose CR, Stephan J. Ca 2+-dependent rapid uncoupling of astrocytes upon brief metabolic stress. Front Cell Neurosci 2023; 17:1151608. [PMID: 37886111 PMCID: PMC10598858 DOI: 10.3389/fncel.2023.1151608] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 08/23/2023] [Indexed: 10/28/2023] Open
Abstract
Astrocytic gap junctional coupling is a major element in neuron-glia interaction. There is strong evidence that impaired coupling is involved in neurological disorders. Reduced coupling was, e.g., demonstrated for core regions of ischemic stroke that suffer from massive cell death. In the surrounding penumbra, cells may recover, but recovery is hampered by spreading depolarizations, which impose additional metabolic stress onto the tissue. Spreading depolarizations are characterized by transient breakdown of cellular ion homeostasis, including pH and Ca2+, which might directly affect gap junctional coupling. Here, we exposed acute mouse neocortical tissue slices to brief metabolic stress and examined its effects on the coupling strength between astrocytes. Changes in gap junctional coupling were assessed by recordings of the syncytial isopotentiality. Moreover, quantitative ion imaging was performed in astrocytes to analyze the mechanisms triggering the observed changes. Our experiments show that a 2-minute perfusion of tissue slices with blockers of glycolysis and oxidative phosphorylation causes a rapid uncoupling in half of the recorded cells. They further indicate that uncoupling is not mediated by the accompanying (moderate) intracellular acidification. Dampening large astrocytic Ca2+ loads by removal of extracellular Ca2+ or blocking Ca2+ influx pathways as well as a pharmacological inhibition of calmodulin, however, prevent the uncoupling. Taken together, we conclude that astrocytes exposed to brief episodes of metabolic stress can undergo a rapid, Ca2+/calmodulin-dependent uncoupling. Such uncoupling may help to confine and reduce cellular damage in the ischemic penumbra in vivo.
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Affiliation(s)
| | | | | | - Christine R. Rose
- Institute of Neurobiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jonathan Stephan
- Institute of Neurobiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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Chatchavalvanich S, Boomsma RA, Tietema JM, Geenen DL. Inhibition of Gap Junction Formation Prior to Implantation of Bone Marrow-Derived Mesenchymal Cells Improves Function in the Ischemic Myocardium. Int J Mol Sci 2023; 24:9653. [PMID: 37298612 PMCID: PMC10253678 DOI: 10.3390/ijms24119653] [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: 04/28/2023] [Revised: 05/22/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
Bone marrow-derived mesenchymal stem cells (BM-MSC) are reported to induce beneficial effects in the heart following ischemia, but a loss of these cells within hours of implantation could significantly diminish their long-term effect. We hypothesized that early coupling between BM-MSC and ischemic cardiomyocytes through gap junctions (GJ) may play an important role in stem cell survival and retention in the acute phase of myocardial ischemia. To determine the effect of GJ inhibition on murine BM-MSC in vivo, we induced ischemia in mice using 90 min left anterior descending coronary artery (LAD) occlusion followed by BM-MSC implantation and reperfusion. The inhibition of GJ coupling prior to BM-MSC implantation led to early improvement in cardiac function compared to mice in which GJ coupling was not inhibited. Our results with in vitro studies also demonstrated increased survival in BM-MSCs subjected to hypoxia after inhibition of GJ. While functional GJ are critical for the long-term integration of stem cells within the myocardium, early GJ communication may represent a novel paradigm whereby ischemic cardiomyocytes induce a "bystander effect" when coupled to newly transplanted BM-MSC and thus impair cell retention and survival.
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Affiliation(s)
- Santipongse Chatchavalvanich
- Department of Basic Biomedical Sciences, Dr. William M. Scholl College of Podiatric Medicine, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA;
| | - Robert A. Boomsma
- Biology Department, Trinity Christian College, Palos Heights, IL 60463, USA;
| | - Jack M. Tietema
- Michigan State University College of Human Medicine, Grand Rapids, MI 49503, USA;
| | - David L. Geenen
- Physician Assistant Studies Department, College of Health Professions, Grand Valley State University, Grand Rapids, MI 49503, USA
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Horhat A, Fischer P, Nicoara-Farcau O, Rusu I, Morar C, Bumbu A, Ignat M, Procopet B, Socaciu C, Sparchez Z, Stefanescu H. Enhanced diagnosis and prognosis of severe alcoholic hepatitis using novel metabolomic biomarkers. Alcohol Alcohol 2023:7152893. [PMID: 37154612 DOI: 10.1093/alcalc/agad034] [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: 02/13/2023] [Revised: 04/11/2023] [Accepted: 04/14/2023] [Indexed: 05/10/2023] Open
Abstract
AIM Differentiating alcoholic hepatitis (AH) from acute decompensation of alcoholic cirrhosis (DC) is challenging, as the presentation and biochemistry are similar. We aimed to identify potential metabolomic biomarkers to differentiate between AH and DC, and to predict short-term mortality. METHODS We included consecutive biopsy proven AH and DC patients, which were managed according to current guidelines and followed up until the end of the study. Untargeted metabolomics was assessed in all patients at baseline. Specific analyses were successively performed to identify potential biomarkers, which were further semi-quantitatively analysed against relevant clinical endpoints. RESULTS Thirty-four patients with AH and 37 with DC were included. UHPLC-MS analysis identified 83 molecules potentially differentiating between AH and DC. C16-Sphinganine-1P (S1P) was the most increased, whereas Prostaglandin E2 (PGE2) was the most decreased. The PGE2/S1P ratio < 1.03 excellently discriminates between AH and DC: AUC 0.965 (p < 0.001), Se 90%, Sp 100%, PPV 0.91, NPV 1, and diagnostic accuracy 95%. This ratio is not influenced by the presence of infection (AUC 0.967 vs. 0.962), correlates with the Lille score at 7 days (r = -0.60; P = 0.022) and tends to be lower in corticosteroid non-responders as compared with patients who responded [0.85(±0.02) vs. 0.89(±0.05), P = 0.069]. Additionally, decreased ursodeoxycholic acid levels are correlated with MELD and Maddrey scores and predict mortality with a 77.27% accuracy (NPV = 100%). CONCLUSION This study suggests the PGE2 (decreased)/S1P (increased) ratio as a biomarker to differentiate AH from DC. The study also finds that low levels of ursodeoxycholic acid could predict increased mortality in AH.
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Affiliation(s)
- Adelina Horhat
- Hepatology Unit, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca 400162, Romania
- Third Medical Clinic, Department of Internal Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca 400347, Romania
- Liver Research Club, Cluj-Napoca 400162, Romania
| | - Petra Fischer
- Hepatology Unit, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca 400162, Romania
- Liver Research Club, Cluj-Napoca 400162, Romania
| | - Oana Nicoara-Farcau
- Hepatology Unit, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca 400162, Romania
- Third Medical Clinic, Department of Internal Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca 400347, Romania
- Liver Research Club, Cluj-Napoca 400162, Romania
| | - Ioana Rusu
- Pathology Unit, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca 400162, Romania
| | - Corina Morar
- Research Centre for Applied Biotechnology in Diagnosis and Molecular Therapy BIODIATECH, Cluj-Napoca 400478, Romania
| | - Andreea Bumbu
- Liver Research Club, Cluj-Napoca 400162, Romania
- First Medical Clinic, Department of Internal Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca 400347, Romania
| | - Mina Ignat
- Hepatology Unit, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca 400162, Romania
- Liver Research Club, Cluj-Napoca 400162, Romania
| | - Bogdan Procopet
- Hepatology Unit, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca 400162, Romania
- Third Medical Clinic, Department of Internal Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca 400347, Romania
- Liver Research Club, Cluj-Napoca 400162, Romania
| | - Carmen Socaciu
- Research Centre for Applied Biotechnology in Diagnosis and Molecular Therapy BIODIATECH, Cluj-Napoca 400478, Romania
| | - Zeno Sparchez
- Hepatology Unit, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca 400162, Romania
- Third Medical Clinic, Department of Internal Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca 400347, Romania
| | - Horia Stefanescu
- Hepatology Unit, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca 400162, Romania
- Liver Research Club, Cluj-Napoca 400162, Romania
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D'Amico D, Barone R, Di Felice V, Ances B, Prideaux B, Eugenin EA. Chronic brain damage in HIV-infected individuals under antiretroviral therapy is associated with viral reservoirs, sulfatide release, and compromised cell-to-cell communication. Cell Mol Life Sci 2023; 80:116. [PMID: 37016051 PMCID: PMC11071786 DOI: 10.1007/s00018-023-04757-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 03/11/2023] [Accepted: 03/13/2023] [Indexed: 04/06/2023]
Abstract
HIV infection has become a chronic and manageable disease due to the effective use of antiretroviral therapies (ART); however, several chronic aging-related comorbidities, including cognitive impairment, remain a major public health issue. However, these mechanisms are unknown. Here, we identified that glial and myeloid viral reservoirs are associated with local myelin damage and the release of several myelin components, including the lipid sulfatide. Soluble sulfatide compromised gap junctional communication and calcium wave coordination, essential for proper cognition. We propose that soluble sulfatide could be a potential biomarker and contributor to white matter compromise observed in HIV-infected individuals even in the current ART era.
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Affiliation(s)
- Daniela D'Amico
- Department of Neurobiology, The University of Texas Medical Branch (UTMB), Research Building 17, Fifth Floor, 11Th Street, Galveston, TX, 77555, USA
- Department of Biomedicine, Neuroscience, and Advanced Diagnostics (BiND), University of Palermo, Palermo, Italy
| | - Rosario Barone
- Department of Biomedicine, Neuroscience, and Advanced Diagnostics (BiND), University of Palermo, Palermo, Italy
| | - Valentina Di Felice
- Department of Biomedicine, Neuroscience, and Advanced Diagnostics (BiND), University of Palermo, Palermo, Italy
| | - Beau Ances
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Brendan Prideaux
- Department of Neurobiology, The University of Texas Medical Branch (UTMB), Research Building 17, Fifth Floor, 11Th Street, Galveston, TX, 77555, USA.
| | - Eliseo A Eugenin
- Department of Neurobiology, The University of Texas Medical Branch (UTMB), Research Building 17, Fifth Floor, 11Th Street, Galveston, TX, 77555, USA.
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Aten S, Du Y, Taylor O, Dye C, Collins K, Thomas M, Kiyoshi C, Zhou M. Chronic Stress Impairs the Structure and Function of Astrocyte Networks in an Animal Model of Depression. Neurochem Res 2023; 48:1191-1210. [PMID: 35796915 PMCID: PMC9823156 DOI: 10.1007/s11064-022-03663-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 06/18/2022] [Indexed: 01/11/2023]
Abstract
Now astrocytes appear to be the key contributors to the pathophysiology of major depression. Evidence in rodents shows that chronic stress is associated with a decreased expression of astrocytic GFAP-immunoreactivity within the cortex in addition to changes in the complexity and length of astrocyte processes. Furthermore, postmortem brains of individuals with depression have revealed a decrease in astrocyte density. Notably, astrocytes are extensively coupled to one another through gap junctions to form a network, or syncytium, and we have previously demonstrated that syncytial isopotentiality is a mechanism by which astrocytes function as an efficient system with respect to brain homeostasis. Interestingly, the question of how astrocyte network function changes following chronic stress is yet to be elucidated. Here, we sought to examine the effects of chronic stress on network-level astrocyte (dys)function. Using a transgenic aldh1l1-eGFP astrocyte reporter mouse, a six-week unpredictable chronic mild stress (UCMS) paradigm as a rodent model of major depression, and immunohistochemical approaches, we show that the morphology of individual astrocytes is altered by chronic stress exposure. Additionally, in astrocyte syncytial isopotentiality measurement, we found that UCMS impairs the syncytial coupling strength of astrocytes within the hippocampus and prefrontal cortex-two brain regions that have been implicated in the regulation of mood. Together, these findings reveal that chronic stress leads to astrocyte atrophy and impaired gap junction coupling, raising the prospect that both individual and network-level astrocyte functionality are important in the etiology of major depression and other neuropsychiatric disorders.
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Affiliation(s)
- Sydney Aten
- Department of Neuroscience, Ohio State University Wexner Medical Center, Graves Hall, Rm 4066C, 333 W. 10th Ave, Columbus, OH, 43210, USA
- Department of Neurology, Division of Sleep Medicine, and Program in Neuroscience, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Yixing Du
- Department of Neuroscience, Ohio State University Wexner Medical Center, Graves Hall, Rm 4066C, 333 W. 10th Ave, Columbus, OH, 43210, USA
| | - Olivia Taylor
- Department of Neuroscience, Ohio State University Wexner Medical Center, Graves Hall, Rm 4066C, 333 W. 10th Ave, Columbus, OH, 43210, USA
| | - Courtney Dye
- Department of Neuroscience, Ohio State University Wexner Medical Center, Graves Hall, Rm 4066C, 333 W. 10th Ave, Columbus, OH, 43210, USA
| | - Kelsey Collins
- Department of Neuroscience, Ohio State University Wexner Medical Center, Graves Hall, Rm 4066C, 333 W. 10th Ave, Columbus, OH, 43210, USA
| | - Matthew Thomas
- Department of Neuroscience, Ohio State University Wexner Medical Center, Graves Hall, Rm 4066C, 333 W. 10th Ave, Columbus, OH, 43210, USA
| | - Conrad Kiyoshi
- Department of Neuroscience, Ohio State University Wexner Medical Center, Graves Hall, Rm 4066C, 333 W. 10th Ave, Columbus, OH, 43210, USA
- Northern Marianas College, Saipan, MP, USA
| | - Min Zhou
- Department of Neuroscience, Ohio State University Wexner Medical Center, Graves Hall, Rm 4066C, 333 W. 10th Ave, Columbus, OH, 43210, USA.
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VanderZwaag J, Halvorson T, Dolhan K, Šimončičová E, Ben-Azu B, Tremblay MÈ. The Missing Piece? A Case for Microglia's Prominent Role in the Therapeutic Action of Anesthetics, Ketamine, and Psychedelics. Neurochem Res 2023; 48:1129-1166. [PMID: 36327017 DOI: 10.1007/s11064-022-03772-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 08/25/2022] [Accepted: 09/27/2022] [Indexed: 11/06/2022]
Abstract
There is much excitement surrounding recent research of promising, mechanistically novel psychotherapeutics - psychedelic, anesthetic, and dissociative agents - as they have demonstrated surprising efficacy in treating central nervous system (CNS) disorders, such as mood disorders and addiction. However, the mechanisms by which these drugs provide such profound psychological benefits are still to be fully elucidated. Microglia, the CNS's resident innate immune cells, are emerging as a cellular target for psychiatric disorders because of their critical role in regulating neuroplasticity and the inflammatory environment of the brain. The following paper is a review of recent literature surrounding these neuropharmacological therapies and their demonstrated or hypothesized interactions with microglia. Through investigating the mechanism of action of psychedelics, such as psilocybin and lysergic acid diethylamide, ketamine, and propofol, we demonstrate a largely under-investigated role for microglia in much of the emerging research surrounding these pharmacological agents. Among others, we detail sigma-1 receptors, serotonergic and γ-aminobutyric acid signalling, and tryptophan metabolism as pathways through which these agents modulate microglial phagocytic activity and inflammatory mediator release, inducing their therapeutic effects. The current review includes a discussion on future directions in the field of microglial pharmacology and covers bidirectional implications of microglia and these novel pharmacological agents in aging and age-related disease, glial cell heterogeneity, and state-of-the-art methodologies in microglial research.
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Affiliation(s)
- Jared VanderZwaag
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Torin Halvorson
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
- BC Children's Hospital Research Institute, Vancouver, BC, Canada
| | - Kira Dolhan
- Department of Psychology, University of Victoria, Vancouver, BC, Canada
- Department of Biology, University of Victoria, Vancouver, BC, Canada
| | - Eva Šimončičová
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Benneth Ben-Azu
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Department of Pharmacology, Faculty of Basic Medical Sciences, College of Health Sciences, Delta State University, Abraka, Delta State, Nigeria
| | - Marie-Ève Tremblay
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada.
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada.
- Axe Neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada.
- Neurology and Neurosurgery Department, McGill University, Montreal, QC, Canada.
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
- Institute for Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
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Chin JS, Milbreta U, Becker DL, Chew SY. Targeting connexin 43 expression via scaffold mediated delivery of antisense oligodeoxynucleotide preserves neurons, enhances axonal extension, reduces astrocyte and microglial activation after spinal cord injury. J Tissue Eng 2023; 14:20417314221145789. [PMID: 36798907 PMCID: PMC9926388 DOI: 10.1177/20417314221145789] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Accepted: 12/01/2022] [Indexed: 02/12/2023] Open
Abstract
Injury to the central nervous system (CNS) provokes an inflammatory reaction and secondary damage that result in further tissue damage and destruction of neurons away from the injury site. Upon injury, expression of connexin 43 (Cx43), a gap junction protein, upregulates and is responsible for the spread and amplification of cell death signals through these gap junctions. In this study, we hypothesise that the downregulation of Cx43 by scaffold-mediated controlled delivery of antisense oligodeoxynucleotide (asODN), would minimise secondary injuries and cell death, and thereby support tissue regeneration after nerve injuries. Specifically, using spinal cord injury (SCI) as a proof-of-principle, we utilised a fibre-hydrogel scaffold for sustained delivery of Cx43asODN, while providing synergistic topographical cues to guide axonal ingrowth. Correspondingly, scaffolds loaded with Cx43asODN, in the presence of NT-3, suppressed Cx43 up-regulation after complete transection SCI in rats. These scaffolds facilitated the sustained release of Cx43asODN for up to 25 days. Importantly, asODN treatment preserved neurons around the injury site, promoted axonal extension, decreased glial scarring, and reduced microglial activation after SCI. Our results suggest that implantation of such scaffold-mediated asODN delivery platform could serve as an effective alternative SCI therapeutic approach.
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Affiliation(s)
- Jiah Shin Chin
- Nanyang Institute of Health Technologies, Interdisciplinary Graduate School, Nanyang Technological University, Singapore,School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore
| | - Ulla Milbreta
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore
| | - David L Becker
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore,Skin Research Institute Singapore, Clinical Sciences Building, Singapore
| | - Sing Yian Chew
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore,School of Materials Science and Engineering, Nanyang Technological University, Singapore,Sing Yian Chew, School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 62 Nanyang Drive, 639798, Singapore.
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11
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Old and Promising Markers Related to Autophagy in Traumatic Brain Injury. Int J Mol Sci 2022; 24:ijms24010072. [PMID: 36613513 PMCID: PMC9820105 DOI: 10.3390/ijms24010072] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/15/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
Traumatic brain injury (TBI) is one of the first causes of death and disability in the world. Because of the lack of macroscopical or histologic evidence of the damage, the forensic diagnosis of TBI could be particularly difficult. Considering that the activation of autophagy in the brain after a TBI is well documented in literature, the aim of this review is to find all autophagy immunohistological protein markers that are modified after TBI to propose a method to diagnose this eventuality in the brain of trauma victims. A systematic literature review on PubMed following PRISMA 2020 guidelines has enabled the identification of 241 articles. In all, 21 of these were enrolled to identify 24 markers that could be divided into two groups. The first consisted of well-known markers that could be considered for a first diagnosis of TBI. The second consisted of new markers recently proposed in the literature that could be used in combination with the markers of the first group to define the elapsed time between trauma and death. However, the use of these markers has to be validated in the future in human tissue by further studies, and the influence of other diseases affecting the victims before death should be explored.
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12
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Zhang NN, Zhang Y, Wang ZZ, Chen NH. Connexin 43: insights into candidate pathological mechanisms of depression and its implications in antidepressant therapy. Acta Pharmacol Sin 2022; 43:2448-2461. [PMID: 35145238 PMCID: PMC9525669 DOI: 10.1038/s41401-022-00861-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 01/06/2022] [Indexed: 11/09/2022] Open
Abstract
Major depressive disorder (MDD), a chronic and recurrent disease characterized by anhedonia, pessimism or even suicidal thought, remains a major chronic mental concern worldwide. Connexin 43 (Cx43) is the most abundant connexin expressed in astrocytes and forms the gap junction channels (GJCs) between astrocytes, the most abundant and functional glial cells in the brain. Astrocytes regulate neurons' synaptic strength and function by expressing receptors and regulating various neurotransmitters. Astrocyte dysfunction causes synaptic abnormalities, which are related to various mood disorders, e.g., depression. Increasing evidence suggests a crucial role of Cx43 in the pathogenesis of depression. Depression down-regulates Cx43 expression in humans and rats, and dysfunction of Cx43 also induces depressive behaviors in rats and mice. Recently Cx43 has received considerable critical attention and is highly implicated in the onset of depression. However, the pathological mechanisms of depression-like behavior associated with Cx43 still remain ambiguous. In this review we summarize the recent progress regarding the underlying mechanisms of Cx43 in the etiology of depression-like behaviors including gliotransmission, metabolic disorders, and neuroinflammation. We also discuss the effects of antidepressants (monoamine antidepressants and ketamine) on Cx43. The clarity of the candidate pathological mechanisms of depression-like behaviors associated with Cx43 and its potential pharmacological roles for antidepressants will benefit the exploration of a novel antidepressant target.
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Affiliation(s)
- Ning-Ning Zhang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
| | - Yi Zhang
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 102488, China
| | - Zhen-Zhen Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China.
| | - Nai-Hong Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China.
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13
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He T, Yang GY, Zhang Z. Crosstalk of Astrocytes and Other Cells during Ischemic Stroke. LIFE (BASEL, SWITZERLAND) 2022; 12:life12060910. [PMID: 35743941 PMCID: PMC9228674 DOI: 10.3390/life12060910] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/04/2022] [Accepted: 06/07/2022] [Indexed: 12/27/2022]
Abstract
Stroke is a leading cause of death and long-term disability worldwide. Astrocytes structurally compose tripartite synapses, blood–brain barrier, and the neurovascular unit and perform multiple functions through cell-to-cell signaling of neurons, glial cells, and vasculature. The crosstalk of astrocytes and other cells is complicated and incompletely understood. Here we review the role of astrocytes in response to ischemic stroke, both beneficial and detrimental, from a cell–cell interaction perspective. Reactive astrocytes provide neuroprotection through antioxidation and antiexcitatory effects and metabolic support; they also contribute to neurorestoration involving neurogenesis, synaptogenesis, angiogenesis, and oligodendrogenesis by crosstalk with stem cells and cell lineage. In the meantime, reactive astrocytes also play a vital role in neuroinflammation and brain edema. Glial scar formation in the chronic phase hinders functional recovery. We further discuss astrocyte enriched microRNAs and exosomes in the regulation of ischemic stroke. In addition, the latest notion of reactive astrocyte subsets and astrocytic activity revealed by optogenetics is mentioned. This review discusses the current understanding of the intimate molecular conversation between astrocytes and other cells and outlines its potential implications after ischemic stroke. “Neurocentric” strategies may not be sufficient for neurological protection and recovery; future therapeutic strategies could target reactive astrocytes.
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Affiliation(s)
- Tingting He
- Department of Neurology, Shanghai Tenth People’s Hospital, Tongji University, Shanghai 200072, China;
- Neuroscience and Neuroengineering Center, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Guo-Yuan Yang
- Neuroscience and Neuroengineering Center, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
- Correspondence: (G.-Y.Y.); (Z.Z.); Tel.: +86-21-62933186 (G.-Y.Y.); Fax: +86-21-62932302 (G.-Y.Y.)
| | - Zhijun Zhang
- Neuroscience and Neuroengineering Center, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
- Correspondence: (G.-Y.Y.); (Z.Z.); Tel.: +86-21-62933186 (G.-Y.Y.); Fax: +86-21-62932302 (G.-Y.Y.)
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14
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Zong P, Lin Q, Feng J, Yue L. A Systemic Review of the Integral Role of TRPM2 in Ischemic Stroke: From Upstream Risk Factors to Ultimate Neuronal Death. Cells 2022; 11:491. [PMID: 35159300 PMCID: PMC8834171 DOI: 10.3390/cells11030491] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 01/26/2022] [Accepted: 01/29/2022] [Indexed: 02/04/2023] Open
Abstract
Ischemic stroke causes a heavy health burden worldwide, with over 10 million new cases every year. Despite the high prevalence and mortality rate of ischemic stroke, the underlying molecular mechanisms for the common etiological factors of ischemic stroke and ischemic stroke itself remain unclear, which results in insufficient preventive strategies and ineffective treatments for this devastating disease. In this review, we demonstrate that transient receptor potential cation channel, subfamily M, member 2 (TRPM2), a non-selective ion channel activated by oxidative stress, is actively involved in all the important steps in the etiology and pathology of ischemic stroke. TRPM2 could be a promising target in screening more effective prophylactic strategies and therapeutic medications for ischemic stroke.
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Affiliation(s)
- Pengyu Zong
- Department of Cell Biology, Calhoun Cardiology Center, University of Connecticut School of Medicine (UConnHealth), Farmington, CT 06030, USA; (P.Z.); (J.F.)
| | - Qiaoshan Lin
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA;
| | - Jianlin Feng
- Department of Cell Biology, Calhoun Cardiology Center, University of Connecticut School of Medicine (UConnHealth), Farmington, CT 06030, USA; (P.Z.); (J.F.)
| | - Lixia Yue
- Department of Cell Biology, Calhoun Cardiology Center, University of Connecticut School of Medicine (UConnHealth), Farmington, CT 06030, USA; (P.Z.); (J.F.)
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15
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Gap Junctions and Hemichannels Composed of Connexins and Pannexins Mediate the Secondary Brain Injury Following Intracerebral Hemorrhage. BIOLOGY 2021; 11:biology11010027. [PMID: 35053024 PMCID: PMC8772966 DOI: 10.3390/biology11010027] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 12/19/2021] [Accepted: 12/24/2021] [Indexed: 12/15/2022]
Abstract
Simple Summary Intracerebral hemorrhage (ICH) is a leading medical problem without effective treatment options. The poor prognosis is attributed to the primary brain injury of the mechanical compression caused by hematoma, and secondary brain injury (SBI) that includes inflammation, glutamate excitotoxicity, oxidative stress and disruption of the blood brain barrier (BBB). Evidences suggests that gap junctions and hemichannels composed of connexins and pannexins regulate the inflammation and excitotoxicity insult in the pathological process of central nervous system disease, such as cerebral ischemia and neurodegeneration disease. In this manuscript, we discuss the fact that connexins- and pannexins-based channels could be involved in secondary brain injury of ICH, particularly through mediating inflammation, oxidative stress, BBB disruption and cell death. The details provided in this manuscript may help develop potential targets for therapeutic intervention of ICH. Abstract Intracerebral hemorrhage (ICH) is a devastating disease with high mortality and morbidity; the mortality rate ranges from 40% at 1 month to 54% at 1 year; only 12–39% achieve good outcomes and functional independence. ICH affects nearly 2 million patients worldwide annually. In ICH development, the blood leakage from ruptured vessels generates sequelae of secondary brain injury (SBI). This mechanism involves activated astrocytes and microglia, generation of reactive oxygen species (ROS), the release of reactive nitrogen species (RNS), and disrupted blood brain barrier (BBB). In addition, inflammatory cytokines and chemokines, heme compounds, and products of hematoma are accumulated in the extracellular spaces, thereby resulting in the death of brain cells. Recent evidence indicates that connexins regulate microglial activation and their phenotypic transformation. Moreover, communications between neurons and glia via gap junctions have crucial roles in neuroinflammation and cell death. A growing body of evidence suggests that, in addition to gap junctions, hemichannels (composed of connexins and pannexins) play a key role in ICH pathogenesis. However, the precise connection between connexin and pannexin channels and ICH remains to be resolved. This review discusses the pathological roles of gap junctions and hemichannels in SBI following ICH, with the intent of discovering effective therapeutic options of strategies to treat ICH.
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16
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Toychiev AH, Batsuuri K, Srinivas M. Gap Junctional Coupling Between Retinal Astrocytes Exacerbates Neuronal Damage in Ischemia-Reperfusion Injury. Invest Ophthalmol Vis Sci 2021; 62:27. [PMID: 34846518 PMCID: PMC8648063 DOI: 10.1167/iovs.62.14.27] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Purpose Retinal astrocytes abundantly express connexin 43 (Cx43), a transmembrane protein that forms gap junction (GJ) channels and unopposed hemichannels. While it is well established that Cx43 is upregulated in retinal injuries, it is unclear whether astrocytic Cx43 plays a role in retinal ganglion cell (RGC) loss associated with injury. Here, we investigated the effect of astrocyte-specific deletion of Cx43 (Cx43KO) and channel inhibitors on RGC loss in retinal ischemia/reperfusion (I/R) injury and assessed changes in expression and GJ channel and hemichannel function that occur in I/R injury. The effect of Cx43 deletion on neural function in the uninjured retina was also assessed. Methods Cx43 expression, astrocyte density and morphology, and RGC death in wild-type and Cx43KO mice after I/R injury were determined using immunohistochemistry and Western blotting. Visual function was assessed using ERG recordings. GJ coupling and hemichannel activity were evaluated using tracer coupling and uptake studies, respectively. Results Loss of RGCs in I/R injury was accompanied by an increase of Cx43 expression in astrocytes. Functional studies indicated that I/R injury augmented astrocytic GJ coupling but not Cx43 hemichannel activity. Importantly, deletion of astrocytic Cx43 improved neuronal survival in acute ischemia but did not affect RGC function in the absence of injury. In support, pharmacologic inhibition of GJ coupling provided neuroprotection in I/R injury. Conclusions The increase in Cx43 expression and GJ coupling during acute I/R injury exacerbates RGC loss. Inhibition of astrocytic Cx43 channels might represent a useful strategy to promote RGC survival in pathologic conditions.
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Affiliation(s)
- Abduqodir H Toychiev
- Department of Biological and Vision Sciences, SUNY College of Optometry, New York, NY, United States
| | - Khulan Batsuuri
- Department of Biological and Vision Sciences, SUNY College of Optometry, New York, NY, United States
| | - Miduturu Srinivas
- Department of Biological and Vision Sciences, SUNY College of Optometry, New York, NY, United States
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17
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Qing C, Xinyi Z, Xuefei Y, Xindong X, Jianhua F. The Specific Connexin 43-Inhibiting Peptide Gap26 Improved Alveolar Development of Neonatal Rats With Hyperoxia Exposure. Front Pharmacol 2021; 12:587267. [PMID: 34290603 PMCID: PMC8287833 DOI: 10.3389/fphar.2021.587267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 04/20/2021] [Indexed: 11/13/2022] Open
Abstract
Bronchopulmonary dysplasia (BPD) is a common devastating pulmonary complication in preterm infants. Alveolar maldevelopment is the crucial pathological change of BPD highly associated with oxidative stress–mediated excessive apoptosis. Cellular injury can be propagated and amplified by gap junction (GJ)–mediated intercellular communication. Connexin 43 (Cx43) is the most ubiquitous and critical GJ protein. Gap26 is a specific Cx43 mimic peptide, playing as a Cx43-GJ inhibitor. We hypothesized that Cx43-GJ was involved in alveolar maldevelopment of BPD via amplifying oxidative stress signaling and inducing excessive apoptosis. Neonatal Sprague Dawley rats were kept in either normoxia (21% O2) or hyperoxia (85% O2) continuously from postnatal day (PN) 1 to 14 in the presence or absence of Gap26. Moreover, RLE-6TN cells (type II alveolar epithelial cells of rats) were cultured in vitro under normoxia (21% O2) or hyperoxia (85% O2). RLE-6TN cells were treated by N-acetyl cysteine (NAC) (a kind of reactive oxygen species (ROS) scavenger) or Gap26. Morphological properties of lung tissue are detected. Markers associated with Cx43 expression, ROS production, the activity of the ASK1-JNK/p38 signaling pathway, and apoptotic level are detected in vivo and in vitro, respectively. In vitro, the ability of GJ-mediated intercellular communication was examined by dye-coupling assay. In vitro, our results demonstrated ROS increased Cx43 expression and GJ-mediated intercellular communication and Gap26 treatment decreased ROS production, inhibited ASK1-JNK/p38 signaling, and decreased apoptosis. In vivo, we found that hyperoxia exposure resulted in increased ROS production and Cx43 expression, activated ASK1-JNK/p38 signaling, and induced excessive apoptosis. However, Gap26 treatment reversed these changes, thus improving alveolar development in neonatal rats with hyperoxia exposure. In summary, oxidative stress increased Cx43 expression and Cx43-GJ–mediated intercellular communication. And Cx43-GJ–mediated intercellular communication amplified oxidative stress signaling, inducing excessive apoptosis via the ASK1-JNK/p38 signaling pathway. The specific connexin 43–inhibiting peptide Gap26 was a novel therapeutic strategy to improve the alveolar development of BPD.
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Affiliation(s)
- Cai Qing
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Zhao Xinyi
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Yu Xuefei
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Xue Xindong
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Fu Jianhua
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
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18
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Astrocyte Networks as Therapeutic Targets in Glaucomatous Neurodegeneration. Cells 2021; 10:cells10061368. [PMID: 34199470 PMCID: PMC8228804 DOI: 10.3390/cells10061368] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/28/2021] [Accepted: 05/30/2021] [Indexed: 11/22/2022] Open
Abstract
Astrocytes are intimately involved in the response to neurodegenerative stress and have become an attractive target for the development of neuroprotective therapies. However, studies often focus on astrocytes as single-cell units. Astrocytes are densely interconnected by gap junctions that are composed primarily of the protein connexin-43 (Cx43) and can function as a broader network of cells. Such networks contribute to a number of important processes, including metabolite distribution and extracellular ionic buffering, and are likely to play an important role in the progression of neurodegenerative disease. This review will focus on the pro-degenerative and pro-survival influence of astrocyte Cx43 in disease progression, with a focus on the roles of gap junctions and hemichannels in the spread of degenerative stress. Finally, we will highlight the specific evidence for targeting these networks in the treatment of glaucomatous neurodegeneration and other optic neuropathies.
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19
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Abstract
Neurotrophic Keratitis (NK) is a degenerative disorder of the cornea characterized by decreased or absent sensory corneal innervation, corneal epitheliopathy and impaired healing.The clinical presentation of NK can range from persistent epithelial defects to corneal perforation and management is often both challenging and protracted. Historically, the management of NK has consisted of non-specific strategies to facilitate corneal epithelial healing such as lubrication, bandage contact lenses and tarsorrhaphy. Recent advances in the development of therapeutics for NK have provided new and efficacious targeted strategies for its management.In this article, we review recombinant human nerve growth factor (Cenegermin), currently approved for clinical use in the United States and Europe, as well as other promising therapeutic options that are in pre-clinical development such as thymosine β4, connexin43 inhibitors, and artificial extracellular matrix components.
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Affiliation(s)
- Thomas H Dohlman
- Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Rohan Bir Singh
- Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Reza Dana
- Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
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20
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Tan MLL, Kwong HL, Ang CC, Tey HL, Lee JSS, Becker DL. Changes in connexin 43 in inflammatory skin disorders: Eczema, psoriasis, and Steven-Johnson syndrome/toxic epidermal necrolysis. Health Sci Rep 2021; 4:e247. [PMID: 33659713 PMCID: PMC7895532 DOI: 10.1002/hsr2.247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 12/23/2020] [Accepted: 01/14/2021] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Connexin 43 (Cx43) plays a central role in the inflammatory response and wound healing. Targeting Cx43 expression reduces inflammation in a variety of injuries. The expression pattern of Cx43 has not been described for many inflammatory skin diseases. OBJECTIVES To describe the expression patterns of Cx43 in eczema, psoriasis, Steven-Johnson syndrome/toxic epidermal necrolysis. METHODS Archival skin biopsies from patients with eczema, psoriasis, and Steven-Johnson syndrome/toxic epidermal necrosis were identified and examined, with sister sections stained for Cx43 and imaged by confocal microscopy. All samples were compared to age and site-matched normal skin controls. RESULTS Epidermal Cx43 is reduced in acute eczema, absent in regions of spongiosis, and is highly elevated in subacute and chronic eczema. In plaque psoriasis, Cx43 is overexpressed in areas with psoriasiform hyperplasia with a fish-scale-like appearance but is lost in regions surrounding neutrophil microabscesses. Cx43 staining is strong in the neutrophils within these microabscesses. In SJS/TEN, Cx43 expression is elevated in areas bordering normal tissue but is rapidly lost in areas of keratinocyte necrosis. CONCLUSIONS Dynamic changes in Cx43 levels are seen in inflammatory skin diseases and may represent future potential therapeutic targets.
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Affiliation(s)
- Mandy L. L. Tan
- Lee Kong Chian School of MedicineNanyang Technological UniversitySingaporeSingapore
- Interdisciplinary Graduate SchoolNanyang Technological UniversitySingaporeSingapore
| | - Hui L. Kwong
- National Skin CentreSingaporeSingapore
- Department of DermatologyChangi General HospitalSingaporeSingapore
| | - Chia C. Ang
- Department of DermatologyChangi General HospitalSingaporeSingapore
| | - Hong L. Tey
- Lee Kong Chian School of MedicineNanyang Technological UniversitySingaporeSingapore
- National Skin CentreSingaporeSingapore
- Yong Loo Lin School of MedicineNational University of SingaporeSingaporeSingapore
| | | | - David L. Becker
- Lee Kong Chian School of MedicineNanyang Technological UniversitySingaporeSingapore
- Skin Research Institute SingaporeSingaporeSingapore
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21
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Tirosh A, Tuncman G, Calay ES, Rathaus M, Ron I, Tirosh A, Yalcin A, Lee YG, Livne R, Ron S, Minsky N, Arruda AP, Hotamisligil GS. Intercellular Transmission of Hepatic ER Stress in Obesity Disrupts Systemic Metabolism. Cell Metab 2021; 33:319-333.e6. [PMID: 33340456 PMCID: PMC7858244 DOI: 10.1016/j.cmet.2020.11.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 07/30/2020] [Accepted: 11/12/2020] [Indexed: 12/22/2022]
Abstract
Endoplasmic reticulum stress (ERS) has a pathophysiological role in obesity-associated insulin resistance. Yet, the coordinated tissue response to ERS remains unclear. Increased connexin 43 (Cx43)-mediated intercellular communication has been implicated in tissue-adaptive and -maladaptive response to various chronic stresses. Here, we demonstrate that in hepatocytes, ERS results in increased Cx43 expression and cell-cell coupling. Co-culture of ER-stressed "donor" cells resulted in intercellular transmission of ERS and dysfunction to ERS-naive "recipient" cells ("bystander response"), which could be prevented by genetic or pharmacologic suppression of Cx43. Hepatocytes from obese mice were able to transmit ERS to hepatocytes from lean mice, and mice lacking liver Cx43 were protected from diet-induced ERS, insulin resistance, and hepatosteatosis. Taken together, our results indicate that in obesity, the increased Cx43-mediated cell-cell coupling allows intercellular propagation of ERS. This novel maladaptive response to over-nutrition exacerbates the tissue ERS burden, promoting hepatosteatosis and impairing whole-body glucose metabolism.
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Affiliation(s)
- Amir Tirosh
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Boston, MA 02115, USA; Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Harvard Medical School, Boston, MA 02115, USA.
| | - Gurol Tuncman
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Ediz S Calay
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Moran Rathaus
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Idit Ron
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Amit Tirosh
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Abdullah Yalcin
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Adnan Menderes Üniversitesi Medical School, Department of Medical Biology, 09100 Aydin, Turkey
| | - Yankun G Lee
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Rinat Livne
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sophie Ron
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Neri Minsky
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ana Paula Arruda
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Gökhan S Hotamisligil
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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22
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How Repair-or-Dispose Decisions Under Stress Can Initiate Disease Progression. iScience 2020; 23:101701. [PMID: 33235980 PMCID: PMC7670198 DOI: 10.1016/j.isci.2020.101701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 07/17/2020] [Accepted: 10/15/2020] [Indexed: 11/20/2022] Open
Abstract
Glia, the helper cells of the brain, are essential in maintaining neural resilience across time and varying challenges: By reacting to changes in neuronal health glia carefully balance repair or disposal of injured neurons. Malfunction of these interactions is implicated in many neurodegenerative diseases. We present a reductionist model that mimics repair-or-dispose decisions to generate a hypothesis for the cause of disease onset. The model assumes four tissue states: healthy and challenged tissue, primed tissue at risk of acute damage propagation, and chronic neurodegeneration. We discuss analogies to progression stages observed in the most common neurodegenerative conditions and to experimental observations of cellular signaling pathways of glia-neuron crosstalk. The model suggests that the onset of neurodegeneration can result as a compromise between two conflicting goals: short-term resilience to stressors versus long-term prevention of tissue damage.
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Courtney CD, Christian-Hinman C. Assessin' the Vexin' Connexin Between Severity of Epilepsy and Hippocampal Gliosis. Epilepsy Curr 2020; 20:294-296. [PMID: 34025243 PMCID: PMC7653651 DOI: 10.1177/1535759720944924] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Constitutive Deletion of Astrocytic Connexins Aggravates Kainate-Induced Epilepsy Deshpande T, Li T, Henning L, Wu Z, Mueller JAL, Seifert G, Steinhäuser C, Bedner P. Glia. 2020. doi:10.1002/glia.23832 The astroglial gap junctional network formed by connexin (Cx) channels plays a central role in regulating neuronal activity and network synchronization. However, its involvement in the development and progression of epilepsy is not yet understood. Loss of interastrocytic gap junction (GJ) coupling has been observed in the sclerotic hippocampus of patients with mesial temporal lobe epilepsy (MTLE) and in mouse models of MTLE, leading to the suggestion that it plays a causative role in the pathogenesis. To further elucidate this clinically relevant question, we investigated consequences of astrocyte disconnection on the time course and severity of kainate-induced MTLE with hippocampal sclerosis (HS) by comparing mice deficient for astrocytic Cx proteins with wild-type (WT) mice. Continuous telemetric EEG recordings and video monitoring performed over a period of 4 weeks after epilepsy induction revealed substantially higher seizure and interictal spike activity during the chronic phase in Cx deficient versus WT mice, while the severity of status epilepticus was not different. Immunohistochemical analysis showed that, despite the elevated chronic seizure activity, astrocyte disconnection did not aggravate the severity of HS. Indeed, the extent of CA1 pyramidal cell loss was similar between the experimental groupsx, while astrogliosis, granule cell dispersion, angiogenesis, and microglia activation were even reduced in Cx deficient as compared to WT mice. Interestingly, seizure-induced neurogenesis in the adult dentate gyrus was also independent of astrocytic Cxs. Together, our data indicate that constitutive loss of GJ coupling between astrocytes promotes neuronal hyperexcitability and attenuates seizure-induced histopathological outcomes.
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Pulpal upregulation of connexin 43 during pulpitis. Clin Oral Investig 2020; 25:1327-1335. [PMID: 32623525 DOI: 10.1007/s00784-020-03439-6] [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: 03/30/2020] [Accepted: 06/26/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVES Connexins are building blocks of membranous channels that form gap junctions and hemichannels. These channels are essential portals for information exchange and coordination during inflammation. Pathologic levels of these conduits may result in excessive inflammation and collateral destruction. This study aimed to analyse temporospatial levels of connexin 43 (Cx43) during pulpitis in extracted human teeth and in a rodent model. A specific interest was directed at the pulpal stroma as it is conserved during vital pulp therapy. MATERIALS AND METHODS Pulpal tissues were attained from human extracted teeth of various pulpal inflammatory stages and fixed for cryosections. Pulpal exposures were created in bilateral maxillary molars in Sprague-Dawley rats. Rats were sacrificed at days 1 to 5 post-exposure. Immunofluorescence histology was performed to detect Cx43, markers for inflammation, and cell death. Immunofluorescent levels in the pulpal stroma at 3 sites (wound/near/far) were matched to pulpal condition (human) or days post-exposure (rodent). RESULTS Cx43 upregulation was observed with increased severity of pulpitis both in humans and rodent model. The upregulation appeared to be global and included distant regions. Elevated levels of neutrophils were present in advanced pulpitis. Apoptosis and necroptosis seem to be upregulated in human samples as Cx43 levels rose. CONCLUSIONS We observed a disseminated upregulation of Cx43 throughout the pulpal stroma as inflammation became advanced. This observation may facilitate cell death signal transfer or represent overt levels of purinergic signalling that leads to pro-inflammatory conditions. CLINICAL RELEVANCE Cx43 downregulation may represent a potential therapeutic approach to enable resolution of pulpal inflammation.
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Kiyoshi C, Tedeschi A. Axon growth and synaptic function: A balancing act for axonal regeneration and neuronal circuit formation in CNS trauma and disease. Dev Neurobiol 2020; 80:277-301. [PMID: 32902152 PMCID: PMC7754183 DOI: 10.1002/dneu.22780] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 12/13/2022]
Abstract
Axons in the adult mammalian central nervous system (CNS) fail to regenerate inside out due to intrinsic and extrinsic neuronal determinants. During CNS development, axon growth, synapse formation, and function are tightly regulated processes allowing immature neurons to effectively grow an axon, navigate toward target areas, form synaptic contacts and become part of information processing networks that control behavior in adulthood. Not only immature neurons are able to precisely control the expression of a plethora of genes necessary for axon extension and pathfinding, synapse formation and function, but also non-neuronal cells such as astrocytes and microglia actively participate in sculpting the nervous system through refinement, consolidation, and elimination of synaptic contacts. Recent evidence indicates that a balancing act between axon regeneration and synaptic function may be crucial for rebuilding functional neuronal circuits after CNS trauma and disease in adulthood. Here, we review the role of classical and new intrinsic and extrinsic neuronal determinants in the context of CNS development, injury, and disease. Moreover, we discuss strategies targeting neuronal and non-neuronal cell behaviors, either alone or in combination, to promote axon regeneration and neuronal circuit formation in adulthood.
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Affiliation(s)
- Conrad Kiyoshi
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Andrea Tedeschi
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
- Discovery Theme on Chronic Brain Injury, The Ohio State University, Columbus, OH 43210, USA
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Rozas-Villanueva MF, Casanello P, Retamal MA. Role of ROS/RNS in Preeclampsia: Are Connexins the Missing Piece? Int J Mol Sci 2020; 21:ijms21134698. [PMID: 32630161 PMCID: PMC7369723 DOI: 10.3390/ijms21134698] [Citation(s) in RCA: 7] [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: 05/29/2020] [Revised: 06/18/2020] [Accepted: 06/28/2020] [Indexed: 12/15/2022] Open
Abstract
Preeclampsia is a pregnancy complication that appears after 20 weeks of gestation and is characterized by hypertension and proteinuria, affecting both mother and offspring. The cellular and molecular mechanisms that cause the development of preeclampsia are poorly understood. An important feature of preeclampsia is an increase in oxygen and nitrogen derived free radicals (reactive oxygen species/reactive nitrogen species (ROS/RNS), which seem to be central players setting the development and progression of preeclampsia. Cell-to-cell communication may be disrupted as well. Connexins (Cxs), a family of transmembrane proteins that form hemichannels and gap junction channels (GJCs), are essential in paracrine and autocrine cell communication, allowing the movement of signaling molecules between cells as well as between the cytoplasm and the extracellular media. GJCs and hemichannels are fundamental for communication between endothelial and smooth muscle cells and, therefore, in the control of vascular contraction and relaxation. In systemic vasculature, the activity of GJCs and hemichannels is modulated by ROS and RNS. Cxs participate in the development of the placenta and are expressed in placental vasculature. However, it is unknown whether Cxs are modulated by ROS/RNS in the placenta, or whether this potential modulation contributes to the pathogenesis of preeclampsia. Our review addresses the possible role of Cxs in preeclampsia, and the plausible modulation of Cxs-formed channels by ROS and RNS. We suggest these factors may contribute to the development of preeclampsia.
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Affiliation(s)
- María F. Rozas-Villanueva
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago 7690000, Chile;
- Programa de Doctorado en Ciencias e Innovación en Medicina, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago 7690000, Chile
| | - Paola Casanello
- Department of Obstetrics, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 7690000, Chile;
- Department of Neonatology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 7690000, Chile
| | - Mauricio A. Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago 7690000, Chile;
- Programa de Comunicación Celular de Cáncer, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago 7690000, Chile
- Correspondence:
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Feng J, Thangaveloo M, Ong YS, Chong SJ, Joethy JV, Becker DL. Connexin 43 upregulation in burns promotes burn conversion through spread of apoptotic death signals. Burns 2020; 46:1389-1397. [PMID: 32362363 DOI: 10.1016/j.burns.2020.03.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 03/04/2020] [Accepted: 03/20/2020] [Indexed: 11/18/2022]
Abstract
BACKGROUND Burn wounds continue to worsen after initial injury in a process known as burn conversion, which lasts about 3-5 days. It causes burn wounds to enlarge and deepen, leading to greater morbidity. Apoptosis is one of the factors contributing to the conversion of the zone of stasis into the zone of coagulation. Suppression of apoptosis has been associated with reducing burn conversion. Connexin 43 (Cx43) gap junctions facilitate the spread of apoptotic signals from dying cells to healthy neighbouring cells in injured tissues through the bystander effect. OBJECTIVES The study is to understand the role of Cx43 in burn conversion. METHODS In our study, 15 burn tissue samples were arranged into three groups as early (beginning of burn conversion), intermediate (extensive burn conversion) and late (established burn conversion) burns. RESULTS We found a striking increase in the amount of Cx43 protein expressed in the dermal fibroblasts (identified with heat shock protein 47 (HSP47) staining) in the zone of stasis in early and intermediate burns. These dermal fibroblasts also express high levels of cleaved-Caspase 3 indicating on-going apoptosis. CONCLUSIONS Our findings suggest that elevation of Cx43 may play an active role in burn conversion spreading apoptosis in the early and intermediate burn wound.
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Affiliation(s)
- Jiajun Feng
- Department of Plastic, Reconstructive & Aesthetic Surgery, Singapore General Hospital, Singapore.
| | - Moogaambikai Thangaveloo
- Lee Kong Chian School of Medicine, Clinical Sciences Building, Nanyang Technological University 11, Mandalay Road, 308232 Singapore
| | - Yee Siang Ong
- Department of Plastic, Reconstructive & Aesthetic Surgery, Singapore General Hospital, Singapore
| | - Si Jack Chong
- Department of Plastic, Reconstructive & Aesthetic Surgery, Singapore General Hospital, Singapore
| | - Janna-Vale Joethy
- Department of Plastic, Reconstructive & Aesthetic Surgery, Singapore General Hospital, Singapore
| | - David L Becker
- Lee Kong Chian School of Medicine, Clinical Sciences Building, Nanyang Technological University 11, Mandalay Road, 308232 Singapore; Skin Research Institute Singapore, Clinical Sciences Building, 11, Mandalay Road, 308232 Singapore
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Traiffort E, Kassoussi A, Zahaf A, Laouarem Y. Astrocytes and Microglia as Major Players of Myelin Production in Normal and Pathological Conditions. Front Cell Neurosci 2020; 14:79. [PMID: 32317939 PMCID: PMC7155218 DOI: 10.3389/fncel.2020.00079] [Citation(s) in RCA: 101] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 03/19/2020] [Indexed: 12/13/2022] Open
Abstract
Myelination is an essential process that consists of the ensheathment of axons by myelin. In the central nervous system (CNS), myelin is synthesized by oligodendrocytes. The proliferation, migration, and differentiation of oligodendrocyte precursor cells constitute a prerequisite before mature oligodendrocytes extend their processes around the axons and progressively generate a multilamellar lipidic sheath. Although myelination is predominately driven by oligodendrocytes, the other glial cells including astrocytes and microglia, also contribute to this process. The present review is an update of the most recent emerging mechanisms involving astrocyte and microglia in myelin production. The contribution of these cells will be first described during developmental myelination that occurs in the early postnatal period and is critical for the proper development of cognition and behavior. Then, we will report the novel findings regarding the beneficial or deleterious effects of astroglia and microglia, which respectively promote or impair the endogenous capacity of oligodendrocyte progenitor cells (OPCs) to induce spontaneous remyelination after myelin loss. Acute delineation of astrocyte and microglia activities and cross-talk should uncover the way towards novel therapeutic perspectives aimed at recovering proper myelination during development or at breaking down the barriers impeding the regeneration of the damaged myelin that occurs in CNS demyelinating diseases.
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Affiliation(s)
| | | | - Amina Zahaf
- U1195 Inserm, University Paris-Saclay, Kremlin-Bicêtre, France
| | - Yousra Laouarem
- U1195 Inserm, University Paris-Saclay, Kremlin-Bicêtre, France
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HIV gp120 Protein Increases the Function of Connexin 43 Hemichannels and Pannexin-1 Channels in Astrocytes: Repercussions on Astroglial Function. Int J Mol Sci 2020; 21:ijms21072503. [PMID: 32260308 PMCID: PMC7178136 DOI: 10.3390/ijms21072503] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/24/2020] [Accepted: 03/27/2020] [Indexed: 11/17/2022] Open
Abstract
At least half of human immunodeficiency virus (HIV)-infected individuals suffer from a wide range of cognitive, behavioral and motor deficits, collectively known as HIV-associated neurocognitive disorders (HAND). The molecular mechanisms that amplify damage within the brain of HIV-infected individuals are unknown. Recently, we described that HIV augments the opening of connexin-43 (Cx43) hemichannels in cultured human astrocytes, which result in the collapse of neuronal processes. Whether HIV soluble viral proteins such as gp120, can regulate hemichannel opening in astrocytes is still ignored. These channels communicate the cytosol with the extracellular space during pathological conditions. We found that gp120 enhances the function of both Cx43 hemichannels and pannexin-1 channels in mouse cortical astrocytes. These effects depended on the activation of IL-1β/TNF-α, p38 MAP kinase, iNOS, cytoplasmic Ca2+ and purinergic signaling. The gp120-induced channel opening resulted in alterations in Ca2+ dynamics, nitric oxide production and ATP release. Although the channel opening evoked by gp120 in astrocytes was reproduced in ex vivo brain preparations, these responses were heterogeneous depending on the CA1 region analyzed. We speculate that soluble gp120-induced activation of astroglial Cx43 hemichannels and pannexin-1 channels could be crucial for the pathogenesis of HAND.
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30
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Deshpande T, Li T, Henning L, Wu Z, Müller J, Seifert G, Steinhäuser C, Bedner P. Constitutive deletion of astrocytic connexins aggravates kainate-induced epilepsy. Glia 2020; 68:2136-2147. [PMID: 32240558 DOI: 10.1002/glia.23832] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/17/2020] [Accepted: 03/17/2020] [Indexed: 01/08/2023]
Abstract
The astroglial gap junctional network formed by connexin (Cx) channels plays a central role in regulating neuronal activity and network synchronization. However, its involvement in the development and progression of epilepsy is not yet understood. Loss of interastrocytic gap junction (GJ) coupling has been observed in the sclerotic hippocampus of patients with mesial temporal lobe epilepsy (MTLE) and in mouse models of MTLE, leading to the suggestion that it plays a causative role in the pathogenesis. To further elucidate this clinically relevant question, we investigated consequences of astrocyte disconnection on the time course and severity of kainate-induced MTLE with hippocampal sclerosis (HS) by comparing mice deficient for astrocytic Cx proteins with wild-type mice (WT). Continuous telemetric EEG recordings and video monitoring performed over a period of 4 weeks after epilepsy induction revealed substantially higher seizure and interictal spike activity during the chronic phase in Cx deficient versus WT mice, while the severity of status epilepticus was not different. Immunohistochemical analysis showed that, despite the elevated chronic seizure activity, astrocyte disconnection did not aggravate the severity of HS. Indeed, the extent of CA1 pyramidal cell loss was similar between the experimental groups, while astrogliosis, granule cell dispersion, angiogenesis, and microglia activation were even reduced in Cx deficient as compared to WT mice. Interestingly, seizure-induced neurogenesis in the adult dentate gyrus was also independent of astrocytic Cxs. Together, our data indicate that constitutive loss of GJ coupling between astrocytes promotes neuronal hyperexcitability and attenuates seizure-induced histopathological outcomes.
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Affiliation(s)
- Tushar Deshpande
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Tingsong Li
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Lukas Henning
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Zhou Wu
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Julia Müller
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Gerald Seifert
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Peter Bedner
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
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Abstract
Traumatic brain injury (TBI) is the leading cause of morbidity and mortality worldwide. Although TBI leads to mechanical damage during initial impact, secondary damage also occurs as results from delayed neurochemical process and intracellular signaling pathways. Accumulated animal and human studies demonstrated that apoptotic mechanism contributes to overall pathology of TBI. Apoptotic cell death has been identified within contusional brain lesion at acute phase of TBI and in region remote from the site directly injured in days to weeks after trauma. TBI is also dynamic conditions that cause neuronal decline overtime and is likely due to neurodegenerative mechanisms years after trauma. Current studies have even suggested association of neuronal damage through apoptotic pathway with mild TBI, which contributes chronic persistent neurological symptoms and cognitive deficits. Thus, a better understanding of the acute and chronic consequences of apoptosis following TBI is required. The purpose of this review is to describe (1) neuronal apoptotic pathway following TBI, (2) contribution of apoptosis to acute and chronic phase of TBI, and (3) current treatment targeting on apoptotic pathway.
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Affiliation(s)
- Yosuke Akamatsu
- Division of Neurosurgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Department of Neurosurgery, Iwate Medical University, Morioka, Japan
| | - Khalid A Hanafy
- Department of Neurology, Harvard Medical School, Boston, MA, USA.
- Division of Neurointensive Care, Beth Israel Deaconess Medical Center, Harvard Medical School, 3 Blackfan Circle Rm 639, Boston, MA, 02115, USA.
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Zheng RF, Du YW, Zeng C, Wang HF, Xing JG, Xu M. Total flavones of Dracocephalum moldavica L. protect astrocytes against H 2O 2-induced apoptosis through a mitochondria-dependent pathway. BMC Complement Med Ther 2020; 20:78. [PMID: 32164676 PMCID: PMC7076740 DOI: 10.1186/s12906-020-2846-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Accepted: 02/09/2020] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The active components of Dracocephalum moldavica L. (TFDM) can inhibit myocardial ischemia by inhibiting oxidative stress. However, the effects of TFDM on astrocytes have not been investigated in vitro. The current study aimed to explore whether TFDM protects astrocytes against H2O2-induced apoptosis through a mitochondria-dependent pathway. METHODS The human glioma cell line U87 was used to investigate the ability of TFDM to protect astrocytes against H2O2-induced apoptosis. The cell counting kit-8 assay and flow cytometry were used to detect cell viability, apoptosis, MMP, Ca2+ influx and reactive oxygen species (ROS). Lactate dehydrogenase (LDH) and malonic dialdehyde (MDA) levels were measured by ELISA. In addition, protein and mRNA expression changes were detected by Western blotting and qRT-PCR. RESULTS TFDM (0.78~200 μg/ml) had limited cytotoxic effects on the viability of U87 cells. Compared with the model group (treated with H2O2 only), cells treated with medium- and high-dose TFDM exhibited reduced MDA concentrations (P < 0.05) and ROS production (P < 0.05) and decreased MMP (P < 0.05) and reduced apoptosis (P < 0.05). The percentage of annexin V-FITC-stained cells was markedly suppressed by TFDM, confirming its anti-apoptotic properties. WB results showed that protein expression of Bcl-2-associated X protein (BAX), Caspase-3, Caspase-9, Caspase-12, and B-cell leukemia/lymphoma 2 (Bcl2) was reduced in the TFDM group compared with that in the model group (P < 0.05) and that expression of these proteins was normalized by TFDM treatment in a dose-dependent manner. According to RT-qPCR results, TFDM pretreatment resulted in reduced mRNA expression of BAX, Caspase-9, Caspase-12, p38MAPK, and CaMKII and increased mRNA expression of mTOR compared with the model group. CONCLUSIONS The current study revealed the protective effects of TFDM on U87 cells under oxidative stress conditions through the inhibition of a mitochondria-dependent pathway that is associated with the CaMKII/P38MAPK/ERK1/2 and PI3K/AKT/mTOR pathways.
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Affiliation(s)
- Rui-Fang Zheng
- Xinjiang Key Laboratory of Uighur Medicines, Xinjiang Institute of Materia Medica, 140 Xinhua South Road, Urumchi, 830004, Xinjiang, China
| | - Yan-Wen Du
- Xinjiang Medical University, Urumchi, 830000, Xinjiang, China.,Xinjiang Key Laboratory of Uighur Medicines, Xinjiang Institute of Materia Medica, 140 Xinhua South Road, Urumchi, 830004, Xinjiang, China
| | - Cheng Zeng
- Xinjiang Medical University, Urumchi, 830000, Xinjiang, China.,Xinjiang Key Laboratory of Uighur Medicines, Xinjiang Institute of Materia Medica, 140 Xinhua South Road, Urumchi, 830004, Xinjiang, China
| | - Hui-Fang Wang
- Department of Clinical Pharmacy, China Pharmaceutical University, 24 Tong jia Lane, P.O. Box 076, Nanjing, 210009, China
| | - Jian-Guo Xing
- Xinjiang Key Laboratory of Uighur Medicines, Xinjiang Institute of Materia Medica, 140 Xinhua South Road, Urumchi, 830004, Xinjiang, China.
| | - Ming Xu
- Department of Clinical Pharmacy, China Pharmaceutical University, 24 Tong jia Lane, P.O. Box 076, Nanjing, 210009, China.
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Cardinal von Widdern J, Hohmann T, Dehghani F. Abnormal Cannabidiol Affects Production of Pro-Inflammatory Mediators and Astrocyte Wound Closure in Primary Astrocytic-Microglial Cocultures. Molecules 2020; 25:E496. [PMID: 31979350 PMCID: PMC7037200 DOI: 10.3390/molecules25030496] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 12/13/2022] Open
Abstract
Abnormal cannabidiol (abn-CBD) exerts neuroprotective effects in vivo and in vitro. In the present study, we investigated the impact of abn-CBD on the glial production of proinflammatory mediators and scar formation within in vitro models. Primary astrocytic-microglial cocultures and astrocytic cultures from neonatal C57BL/6 mice and CB2 receptor knockout mice were stimulated with lipopolysaccharide (LPS), and the concentrations of tumor necrosis factor α (TNFα), interleukin-6 (IL-6) and nitrite were determined. Furthermore, we performed a live cell microscopy-based scratch-wound assay. After LPS stimulation, TNFα, IL-6 and nitrite production was more strongly increased in cocultures than in isolated astrocytes. Abn-CBD treatment attenuated the LPS-induced production of TNFα and nitrite in cocultures, while IL-6 production remained unaltered. In isolated astrocytes, only LPS-induced TNFα production was reduced by abn-CBD. Similar effects were observed after abn-CBD application in cocultures of CB2 knockout mice. Interestingly, LPS-induced TNFα and nitrite levels were far lower in CB2 knockout cultures compared to wildtypes, while IL-6 levels did not differ. In the scratch-wound assay, treatment with abn-CBD decelerated wound closure when microglial cells were present. Our data shows a differential role of abn-CBD for modulation of glial inflammation and astrocytic scar formation. These findings provide new explanations for mechanisms behind the neuroprotective potential of abn-CBD.
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Affiliation(s)
| | | | - Faramarz Dehghani
- Department of Anatomy and Cell Biology, Martin Luther University Halle-Wittenberg, 06097 Halle (Saale), Germany; (J.C.v.W.); (T.H.)
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Wang M, Qin C, Luo X, Wang J, Wang X, Xie M, Hu J, Cao J, Hu T, Goldman SA, Nedergaard M, Wang W. Astrocytic connexin 43 potentiates myelin injury in ischemic white matter disease. Am J Cancer Res 2019; 9:4474-4493. [PMID: 31285774 PMCID: PMC6599652 DOI: 10.7150/thno.31942] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 04/19/2019] [Indexed: 01/05/2023] Open
Abstract
Rational: Myelin loss is a characteristic feature of both ischemic white matter disease and its associated vascular dementia, and is a hallmark of chronic cerebral hypoperfusion due to carotid artery stenosis. Yet the cellular mechanisms involved in ischemic dysmyelination are not well-understood, and no effective treatment has emerged to prevent or slow hypoperfusion-related demyelination. In a study employing the bilateral common carotid artery stenosis (BCAS) mouse model, we found reduced cerebral blood flow velocity and arteriolar pulsatility, and confirmed that prolonged BCAS provoked myelin disruption. These pathological features were associated with marked cognitive decline, in the absence of evident damage to axons. Methods: To assess the role of astroglial communication in BCAS-associated demyelination, we investigated the effect of deleting or inhibiting connexin 43 (Cx43), a constituent of astroglial gap junctions and hemichannels. Results: Genetic deletion and pharmacological inhibition of gap junctions both protected myelin integrity and rescued cognitive decline in the BCAS-treated mice. Gap junction inhibition also suppressed the transient increase in extracellular glutamate observed in the callosal white matter of wild-type mice exposed to BCAS. Conclusion: These findings suggest that astrocytic Cx43 may be a viable target for attenuating the demyelination and cognitive decline associated with chronic cerebral hypoperfusion.
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Abbasi Y, Shabani R, Mousavizadeh K, Soleimani M, Mehdizadeh M. Neuroprotective effect of ethanol and Modafinil on focal cerebral ischemia in rats. Metab Brain Dis 2019; 34:805-819. [PMID: 30644018 DOI: 10.1007/s11011-018-0378-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 12/26/2018] [Indexed: 01/08/2023]
Abstract
Ethanol is known as an effective agent against cerebral lesions after ischemia. Modafinil is a stimulant of the central nervous system (CNS) with antioxidant properties. We assessed the neuroprotective effect of modafinil in combination with ethanol after focal cerebral ischemia. Male wistar rats weighing 280-300 g were divided into nine groups (n = 12 each group): The groups consisted of the MCAO (middle cerebral artery occlusion) group (i.e. ischemia without treatment); the vehicle group(Dimethylsulfoxide); the modafinil group including three subgroups which pretreated with Modafinil (10, 30, 100 mg/kg), respectively, for seven days prior to the induction of MCAO; the ethanol group which received 1.5g/kg ethanol at the time of reperfusion; and modafinil+ethanol group which was divided into three subgroups that received three doses of modanifil (10, 30,100 mg/kg), respectively, for seven days prior to MCAO as well as ethanol at the time of reperfusion. Transient cerebral ischemia was induced by 60-min intraluminal occlusion of the right middle cerebral artery. Edema, infarct volume, glial scar formation (gliosis) and apoptosis were analyzed. The ethanol alone treatment (with a less significant effect), modafinil (in a dose-dependent way), and the combination of modafinil and ethanol significantly decreased the brain infarct volume, edema, apoptosis, and gliosis (P ≤ 0.05). Additionally, modafinil+ethanol mediated the restoration of aerobic metabolism and hyper-glycolysis suppress, thereby resulting in an increase in pyruvate dehydrogenase and a decrease in lactate dehydrogenase activity, respectively, which ultimately reduced oxidative reperfusion injury. These results demonstrate that pretreatment with modafinil (100 mg/kg) and modafinil+ethanol(1.5 g/kg) may prevent ischemic brain injuries.
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Affiliation(s)
- Yusef Abbasi
- Department of Anatomy, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Ronak Shabani
- Department of Anatomy, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
- Cellular and Molecular Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Kazem Mousavizadeh
- Cellular and Molecular Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
- Department of Molecular Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mansoureh Soleimani
- Department of Anatomy, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
- Cellular and Molecular Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mehdi Mehdizadeh
- Department of Anatomy, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
- Cellular and Molecular Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
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36
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Hernández-Guerra M, Hadjihambi A, Jalan R. Gap junctions in liver disease: Implications for pathogenesis and therapy. J Hepatol 2019; 70:759-772. [PMID: 30599172 DOI: 10.1016/j.jhep.2018.12.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 12/03/2018] [Accepted: 12/12/2018] [Indexed: 02/07/2023]
Abstract
In the normal liver, cells interact closely through gap junctions. By providing a pathway for the trafficking of low molecular mass molecules, these channels contribute to tissue homeostasis and maintenance of hepatic function. Thus, dysfunction of gap junctions affects a wide variety of liver processes, such as differentiation, cell death, inflammation and fibrosis. In fact, dysfunctional gap junctions have been implicated, for more than a decade, in cholestatic disease, hepatic cancer and cirrhosis. Additionally, in recent years there is an increasing body of evidence that these channels are also involved in other relevant and prevalent liver pathological processes, such as non-alcoholic fatty liver disease, acute liver injury and portal hypertension. In parallel to these new clinical implications the available data include controversial observations. Thus, a comprehensive overview is required to better understand the functional complexity of these pores. This paper will review the most recent knowledge concerning gap junction dysfunction, with a special focus on the role of these channels in the pathogenesis of relevant clinical entities and on potential therapeutic targets that are amenable to modification by drugs.
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Affiliation(s)
| | | | - Rajiv Jalan
- UCL Institute for Liver and Digestive Health, Royal Free Medical School, London, UK
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37
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Tang N, Cai Z, Chen H, Cao L, Chen B, Lin B. Involvement of gap junctions in propylthiouracil-induced cytotoxicity in BRL-3A cells. Exp Ther Med 2019; 17:2799-2806. [PMID: 30906468 DOI: 10.3892/etm.2019.7244] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 01/14/2019] [Indexed: 12/27/2022] Open
Abstract
Gap junctions (GJs), which are important plasma membrane channels for the transfer of signaling molecules between adjacent cells, have been implicated in drug-induced liver injury. However, the influence and the underlying mechanisms of GJs in propylthiouracil (PTU)-induced hepatotoxicity are unclear. In the present study, distinct manipulations were performed to regulate GJ function in the BRL-3A rat liver cell line. The results indicated that the toxic effect of PTU in BRL-3A cells was mediated by GJ intercellular communication, as cell death was significantly attenuated in the absence of functional GJ channels. Furthermore, the specific knockdown of connexin-32 (Cx32; a major GJ component protein in hepatocytes) using small interfering RNA was observed to decrease necrosis, intracellular PTU content and the level of reactive oxygen species (ROS) following PTU exposure. These observations demonstrated that suppressing GJ Cx32 could confer protection against PTU-induced cytotoxicity through decreasing the accumulation of PTU and ROS. To the best of our knowledge, the present study is the first to demonstrate the role and possible underlying mechanisms of GJs in the regulation of PTU-induced toxicity in BRL-3A rat liver cells.
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Affiliation(s)
- Nan Tang
- School of Pharmacy, Guangdong Medical University, Dongguan, Guangdong 523808, P.R. China
| | - Ziqing Cai
- School of Pharmacy, Guangdong Medical University, Dongguan, Guangdong 523808, P.R. China
| | - Hongpeng Chen
- School of Information Engineering, Guangdong Medical University, Dongguan, Guangdong 523808, P.R. China
| | - Longbin Cao
- School of Basic Medical Sciences, Guangdong Medical University, Dongguan, Guangdong 523808, P.R. China
| | - Bo Chen
- School of Basic Medical Sciences, Guangdong Medical University, Dongguan, Guangdong 523808, P.R. China
| | - Bihua Lin
- School of Basic Medical Sciences, Guangdong Medical University, Dongguan, Guangdong 523808, P.R. China
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38
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Dispelling myths about connexins, pannexins and P2X7 in hypoxic-ischemic central nervous system. Neurosci Lett 2019; 695:76-85. [PMID: 29195910 DOI: 10.1016/j.neulet.2017.11.044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 10/07/2017] [Accepted: 11/21/2017] [Indexed: 01/17/2023]
Abstract
In membrane physiology, as in other fields, myths or speculations may be repeated so often and so widely that they are perceived as facts. To some extent, this has occurred with regard to gap junctions, hemichannels, pannexin channels and P2X7 (ionotropic receptors), especially concerning the interpretation of the individual role of these channels in hypoxic-ischemic CNS since these channels may be closed by the same pharmacological blockers. Significance of existing controversial data are highlighted and contradictory views from different groups are critically discussed herein.
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39
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Macro scale modelling of cortical spreading depression and the role of astrocytic gap junctions. J Theor Biol 2018; 458:78-91. [DOI: 10.1016/j.jtbi.2018.09.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 08/08/2018] [Accepted: 09/07/2018] [Indexed: 12/22/2022]
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40
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De Paepe C, Aberkane A, Dewandre D, Essahib W, Sermon K, Geens M, Verheyen G, Tournaye H, Van de Velde H. BMP4 plays a role in apoptosis during human preimplantation development. Mol Reprod Dev 2018; 86:53-62. [DOI: 10.1002/mrd.23081] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 10/24/2018] [Indexed: 01/04/2023]
Affiliation(s)
- C. De Paepe
- Research Group of Reproduction and Genetics, Vrije Universiteit Brussel (VUB); Brussels Belgium
| | - A. Aberkane
- Research Group of Reproduction and Immunology, Vrije Universiteit Brussel (VUB); Brussels Belgium
| | - D. Dewandre
- Research Group of Reproduction and Genetics, Vrije Universiteit Brussel (VUB); Brussels Belgium
| | - W. Essahib
- Research Group of Reproduction and Immunology, Vrije Universiteit Brussel (VUB); Brussels Belgium
| | - K. Sermon
- Research Group of Reproduction and Genetics, Vrije Universiteit Brussel (VUB); Brussels Belgium
| | - M. Geens
- Research Group of Reproduction and Genetics, Vrije Universiteit Brussel (VUB); Brussels Belgium
| | - G. Verheyen
- Centre for Reproductive Medicine (CRG), UZ Brussel; Brussels Belgium
| | - H. Tournaye
- Centre for Reproductive Medicine (CRG), UZ Brussel; Brussels Belgium
| | - H. Van de Velde
- Research Group of Reproduction and Genetics, Vrije Universiteit Brussel (VUB); Brussels Belgium
- Research Group of Reproduction and Immunology, Vrije Universiteit Brussel (VUB); Brussels Belgium
- Centre for Reproductive Medicine (CRG), UZ Brussel; Brussels Belgium
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41
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Yin X, Feng L, Ma D, Yin P, Wang X, Hou S, Hao Y, Zhang J, Xin M, Feng J. Roles of astrocytic connexin-43, hemichannels, and gap junctions in oxygen-glucose deprivation/reperfusion injury induced neuroinflammation and the possible regulatory mechanisms of salvianolic acid B and carbenoxolone. J Neuroinflammation 2018; 15:97. [PMID: 29587860 PMCID: PMC5872583 DOI: 10.1186/s12974-018-1127-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/12/2018] [Indexed: 02/07/2023] Open
Abstract
Background Glia-mediated neuroinflammation is related to brain injury exacerbation after cerebral ischemia/reperfusion (I/R) injury. Astrocytic hemichannels or gap junctions, which were mainly formed by connexin-43, have been implicated in I/R damage. However, the exact roles of astrocytic hemichannels and gap junction in neuroinflammatory responses induced by I/R injury remain unknown. Methods Primary cultured astrocytes were subjected to OGD/R injury, an in vitro model of I/R injury. Salvianolic acid B (SalB) or carbenoxolone (CBX) were applied for those astrocytes. Besides, Cx43 mimetic peptides Gap19 or Gap26 were also applied during OGD/R injury; Cx43 protein levels were determined by western blot and cytoimmunofluorescene staining, hemichannel activities by Ethidium bromide uptake and ATP concentration detection, and gap junction intercellular communication (GJIC) permeability by parachute assay. Further, astrocyte-conditioned medium (ACM) was collected and incubated with microglia. Meanwhile, ATP or apyrase were applied to explore the role of ATP during OGD/R injury. Microglial activation, M1/M2 phenotypes, and M1/M2-related cytokines were detected. Also, microglia-conditioned medium (MEM) was collected and incubated with astrocytes to further investigate its influence on astrocytic hemichannel activity and GJIC permeability. Lastly, effects of ACM and MCM on neuronal viability were detected by flow cytometry. Results We found that OGD/R induced abnormally opened hemichannels with increased ATP release and EtBr uptake but reduced GJIC permeability. WB tests showed decreased astrocytic plasma membrane’s Cx43, while showing an increase in cytoplasma. Treating OGD/R-injured microglia with ATP or OGD/R-ACM induced further microglial activation and secondary pro-inflammatory cytokine release, with the M1 phenotype predominating. Conversely, astrocytes incubated with OGD/R-MCM exhibited increased hemichannel opening but reduced GJIC coupling. Both SalB and CBX inhibited abnormal astrocytic hemichannel opening and ATP release and switched the activated microglial phenotype from M1 to M2, thus providing effective neuroprotection. Application of Gap19 or Gap26 showed similar results with CBX. We also found that OGD/R injury caused both plasma membrane p-Cx43(Ser265) and p-Src(Tyr416) significantly upregulated; application of SalB may be inhibiting Src kinase and attenuating Cx43 internalization. Meanwhile, CBX treatment induced obviously downregulation of p-Cx43(Ser368) and p-PKC(Ser729) protein levels in plasma membrane. Conclusions We propose a vicious cycle exists between astrocytic hemichannel and microglial activation after OGD/R injury, which would aggravate neuroinflammatory responses and neuronal damage. Astrocytic Cx43, hemichannels, and GJIC play critical roles in OGD/R injury-induced neuroinflammatory responses; treatment differentially targeting astrocytic Cx43, hemichannels, and GJIC may provide novel avenues for therapeutics during cerebral I/R injury. Electronic supplementary material The online version of this article (10.1186/s12974-018-1127-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xiang Yin
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Liangshu Feng
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Di Ma
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Ping Yin
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Xinyu Wang
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Shuai Hou
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Yulei Hao
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Jingdian Zhang
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Meiying Xin
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China
| | - Jiachun Feng
- Department of Neurology and Neuroscience Center, the First Hospital of Jilin University, Changchun, Jilin Province, 130021, People's Republic of China.
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42
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Smith NA, Kress BT, Lu Y, Chandler-Militello D, Benraiss A, Nedergaard M. Fluorescent Ca 2+ indicators directly inhibit the Na,K-ATPase and disrupt cellular functions. Sci Signal 2018; 11:11/515/eaal2039. [PMID: 29382785 DOI: 10.1126/scisignal.aal2039] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Fluorescent Ca2+ indicators have been essential for the analysis of Ca2+ signaling events in various cell types. We showed that chemical Ca2+ indicators, but not a genetically encoded Ca2+ indicator, potently suppressed the activity of Na+- and K+-dependent adenosine triphosphatase (Na,K-ATPase), independently of their Ca2+ chelating activity. Loading of commonly used Ca2+ indicators, including Fluo-4 acetoxymethyl (AM), Rhod-2 AM, and Fura-2 AM, and of the Ca2+ chelator BAPTA AM into cultured mouse or human neurons, astrocytes, cardiomyocytes, or kidney proximal tubule epithelial cells suppressed Na,K-ATPase activity by 30 to 80%. Ca2+ indicators also suppressed the agonist-induced activation of the Na,K-ATPase, altered metabolic status, and caused a dose-dependent loss of cell viability. Loading of Ca2+ indicators into mice, which is carried out for two-photon imaging, markedly altered brain extracellular concentrations of K+ and ATP. These results suggest that a critical review of data obtained with chemical Ca2+ indicators may be necessary.
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Affiliation(s)
- Nathan A Smith
- Center for Translational Neuromedicine, Departments of Neurosurgery and Neurology, University of Rochester Medical Center, Rochester, NY 14642, USA.,Center for Neuroscience Research, Children's Research Institute, Children's National Health System, Washington, DC 20010, USA
| | - Benjamin T Kress
- Center for Translational Neuromedicine, Departments of Neurosurgery and Neurology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Yuan Lu
- Center for Translational Neuromedicine, Departments of Neurosurgery and Neurology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Devin Chandler-Militello
- Center for Translational Neuromedicine, Departments of Neurosurgery and Neurology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Abdellatif Benraiss
- Center for Translational Neuromedicine, Departments of Neurosurgery and Neurology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, Departments of Neurosurgery and Neurology, University of Rochester Medical Center, Rochester, NY 14642, USA.
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43
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Garciarena CD, Malik A, Swietach P, Moreno AP, Vaughan-Jones RD. Distinct moieties underlie biphasic H + gating of connexin43 channels, producing a pH optimum for intercellular communication. FASEB J 2018; 32:1969-1981. [PMID: 29183963 PMCID: PMC5893178 DOI: 10.1096/fj.201700876r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Most mammalian cells can intercommunicate via connexin-assembled, gap-junctional channels. To regulate signal transmission, connexin (Cx) channel permeability must respond dynamically to physiological and pathophysiological stimuli. One key stimulus is intracellular pH (pHi), which is modulated by a tissue’s metabolic and perfusion status. Our understanding of the molecular mechanism of H+ gating of Cx43 channels—the major isoform in the heart and brain—is incomplete. To interrogate the effects of acidic and alkaline pHi on Cx43 channels, we combined voltage-clamp electrophysiology with pHi imaging and photolytic H+ uncaging, performed over a range of pHi values. We demonstrate that Cx43 channels expressed in HeLa or N2a cell pairs are gated biphasically by pHivia a process that consists of activation by H+ ions at alkaline pHi and inhibition at more acidic pHi. For Cx43 channel–mediated solute/ion transmission, the ensemble of these effects produces a pHi optimum, near resting pHi. By using Cx43 mutants, we demonstrate that alkaline gating involves cysteine residues of the C terminus and is independent of motifs previously implicated in acidic gating. Thus, we present a molecular mechanism by which cytoplasmic acid–base chemistry fine tunes intercellular communication and establishes conditions for the optimal transmission of solutes and signals in tissues, such as the heart and brain.—Garciarena, C. D., Malik, A., Swietach, P., Moreno, A. P., Vaughan-Jones, R. D. Distinct moieties underlie biphasic H+ gating of connexin43 channels, producing a pH optimum for intercellular communication.
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Affiliation(s)
- Carolina D Garciarena
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, United Kingdom.,Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Akif Malik
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, United Kingdom
| | - Pawel Swietach
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, United Kingdom
| | - Alonso P Moreno
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah, USA
| | - Richard D Vaughan-Jones
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, United Kingdom
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44
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Johnson AM, Roach JP, Hu A, Stamatovic SM, Zochowski MR, Keep RF, Andjelkovic AV. Connexin 43 gap junctions contribute to brain endothelial barrier hyperpermeability in familial cerebral cavernous malformations type III by modulating tight junction structure. FASEB J 2018; 32:2615-2629. [PMID: 29295866 DOI: 10.1096/fj.201700699r] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Familial cerebral cavernous malformations type III (fCCM3) is a disease of the cerebrovascular system caused by loss-of-function mutations in ccm3 that result in dilated capillary beds that are susceptible to hemorrhage. Before hemorrhage, fCCM3 lesions are characterized by a hyperpermeable blood-brain barrier (BBB), the key pathologic feature of fCCM3. We demonstrate that connexin 43 (Cx43), a gap junction (GJ) protein that is incorporated into the BBB junction complex, is up-regulated in lesions of a murine model of fCCM3. Small interfering RNA-mediated ccm3 knockdown (CCM3KD) in brain endothelial cells in vitro increased Cx43 protein expression, GJ plaque size, GJ intracellular communication (GJIC), and barrier permeability. CCM3KD hyperpermeability was rescued by GAP27, a peptide gap junction and hemichannel inhibitor of Cx43 GJIC. Tight junction (TJ) protein, zonula occludens 1 (ZO-1), accumulated at Cx43 GJs in CCM3KD cells and displayed fragmented staining at TJs. The GAP27-mediated inhibition of Cx43 GJs in CCM3KD cells restored ZO-1 to TJ structures and reduced plaque accumulation at Cx43 GJs. The TJ protein, Claudin-5, was also fragmented at TJs in CCM3KD cells, and GAP27 treatment lengthened TJ-associated fragments and increased Claudin 5-Claudin 5 transinteraction. Overall, we demonstrate that Cx43 GJs are aberrantly increased in fCCM3 and regulate barrier permeability by a TJ-dependent mechanism.-Johnson, A. M., Roach, J. P., Hu, A., Stamatovic, S. M., Zochowski, M. R., Keep, R. F., Andjelkovic, A. V. Connexin 43 gap junctions contribute to brain endothelial barrier hyperpermeability in familial cerebral cavernous malformations type III by modulating tight junction structure.
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Affiliation(s)
- Allison M Johnson
- Department of Pathology, Medical School, University of Michigan, Ann Arbor, Michigan, USA
| | - James P Roach
- Neuroscience Graduate Program, Medical School, University of Michigan, Ann Arbor, Michigan, USA
| | - Anna Hu
- Department of Pathology, Medical School, University of Michigan, Ann Arbor, Michigan, USA
| | - Svetlana M Stamatovic
- Department of Pathology, Medical School, University of Michigan, Ann Arbor, Michigan, USA
| | - Michal R Zochowski
- Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan, USA
| | - Richard F Keep
- Department of Neurosurgery, Medical School, University of Michigan, Ann Arbor, Michigan, USA.,Department of Molecular and Integrative Physiology, Medical School, University of Michigan, Ann Arbor, Michigan, USA
| | - Anuska V Andjelkovic
- Department of Pathology, Medical School, University of Michigan, Ann Arbor, Michigan, USA.,Department of Neurosurgery, Medical School, University of Michigan, Ann Arbor, Michigan, USA
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45
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Vicario N, Zappalà A, Calabrese G, Gulino R, Parenti C, Gulisano M, Parenti R. Connexins in the Central Nervous System: Physiological Traits and Neuroprotective Targets. Front Physiol 2017; 8:1060. [PMID: 29326598 PMCID: PMC5741605 DOI: 10.3389/fphys.2017.01060] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/04/2017] [Indexed: 01/22/2023] Open
Abstract
Cell-to-cell interaction and cell-to-extracellular environment communication are emerging as new therapeutic targets in neurodegenerative disorders. Dynamic expression of connexins leads to distinctive hemichannels and gap junctions, characterized by cell-specific conduction, exchange of stimuli or metabolites, and particular channel functions. Herein, we briefly reviewed classical physiological traits and functions of connexins, hemichannels, and gap junctions, in order to discuss the controversial role of these proteins and their mediated interactions during neuroprotection, with a particular focus on Cx43-based channels. We pointed out the contribution of connexins in neural cells populations during neurodegenerative processes to explore potential neuroprotective therapeutic applications.
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Affiliation(s)
- Nunzio Vicario
- Section of Physiology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Agata Zappalà
- Section of Physiology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Giovanna Calabrese
- Section of Physiology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Rosario Gulino
- Section of Physiology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Carmela Parenti
- Department of Drug Sciences, University of Catania, Catania, Italy
| | - Massimo Gulisano
- Section of Physiology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy.,Department of Drug Sciences, University of Catania, Catania, Italy
| | - Rosalba Parenti
- Section of Physiology, Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
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46
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JAK2/STAT3 pathway is involved in the protective effects of epidermal growth factor receptor activation against cerebral ischemia/reperfusion injury in rats. Neurosci Lett 2017; 662:219-226. [PMID: 29061394 DOI: 10.1016/j.neulet.2017.10.037] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 10/16/2017] [Accepted: 10/19/2017] [Indexed: 12/14/2022]
Abstract
Cerebral ischemia and reperfusion is a common pathophysiologic process, which is involved in stroke and brain trauma. Recent studies revealed that activating epidermal growth factor receptor (EGFR) ameliorates cerebral ischemia/reperfusion (I/R) injury, however, the precise mechanisms remain to be illuminated. In this study, the neurological behavior was evaluated by Longa score. The infarct volume was performed by 2, 3, 5-triphenyltetrazolium chloride (TTC) staining and the expression of p-EGFR, p-STAT3, connexin (Cx43), Bax and Bcl-2 were detected by Western blot. The neurological behavior and infarct volume were increased in rats with cerebral I/R injury. Epidermal growth factor (EGF) pretreatment significantly decreased neurological deficit and infarct volume. However, the antagonist of EGFR, AG1478 attenuated the EGF-induced reduction of neurological deficit and infarct volume. Moreover, the inhibitor of JAK2/STAT3, AG490 undermined the protective effects stimulated by activating EGFR in rats with I/R injury. In addition, EGF pretreatment increased the expression of Bcl-2 and reduced the expression of Bax and Cx43, and the effects were abolished after using AG1478 and AG490. These findings implicate that JAK2/STAT3 pathway plays the vital role in I/R injury protection from activating EGFR. And the neuroprotective effects may associate with inhibiting the Cx43 expression and the inhibition of apoptosis.
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47
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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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48
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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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49
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Neuhaus AA, Couch Y, Hadley G, Buchan AM. Neuroprotection in stroke: the importance of collaboration and reproducibility. Brain 2017. [DOI: 10.1093/brain/awx126] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Ain A Neuhaus
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Yvonne Couch
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Gina Hadley
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Alastair M Buchan
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Medical Sciences Division, University of Oxford, Oxford, UK
- Acute Vascular Imaging Centre, University of Oxford, Oxford University Hospitals, Oxford, UK
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50
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Rodríguez-Sinovas A, Ruiz-Meana M, Denuc A, García-Dorado D. Mitochondrial Cx43, an important component of cardiac preconditioning. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017. [PMID: 28642043 DOI: 10.1016/j.bbamem.2017.06.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Connexin 43 (Cx43) forms gap junction channels that are essential for the propagation of electrical depolarization in cardiomyocytes, but also with important roles in the pathophysiology of reperfusion injury. However, more recent studies have shown that Cx43 has also important functions independent from intercellular communication between adjacent cardiomyocytes. Some of these actions have been related to the presence of Cx43 in the mitochondria of these cells (mitoCx43). The functions of mitoCx43 have not been completely elucidated, but there is strong evidence indicating that mitoCx43 modulates mitochondrial respiration at respiratory complex I, production of radical oxygen species and ATP synthesis. These functions of mitoCx43 modulate mitochondrial and cellular tolerance to reperfusion after prolonged ischemia and are necessary for the cardioprotective effect of ischemic preconditioning. In the present review article we discuss available knowledge on these functions of mitoCx43 in relation to reperfusion injury, the molecular mechanisms involved and explore the possibility that mitoCx43 may constitute a new pharmacological target in patients with ST-segment elevation myocardial infarction (STEMI). This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Antonio Rodríguez-Sinovas
- Cardiovascular Diseases Research Group, Department of Cardiology, Vall d'Hebron University Hospital and Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Cardiovasculares (CIBERCV), Spain
| | - Marisol Ruiz-Meana
- Cardiovascular Diseases Research Group, Department of Cardiology, Vall d'Hebron University Hospital and Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Cardiovasculares (CIBERCV), Spain
| | - Amanda Denuc
- Cardiovascular Diseases Research Group, Department of Cardiology, Vall d'Hebron University Hospital and Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - David García-Dorado
- Cardiovascular Diseases Research Group, Department of Cardiology, Vall d'Hebron University Hospital and Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Cardiovasculares (CIBERCV), Spain.
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