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Chen Y, Luan P, Liu J, Wei Y, Wang C, Wu R, Wu Z, Jing M. Spatiotemporally selective astrocytic ATP dynamics encode injury information sensed by microglia following brain injury in mice. Nat Neurosci 2024; 27:1522-1533. [PMID: 38862791 DOI: 10.1038/s41593-024-01680-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 05/13/2024] [Indexed: 06/13/2024]
Abstract
Injuries to the brain result in tunable cell responses paired with stimulus properties, suggesting the existence of intrinsic processes that encode and transmit injury information; however, the molecular mechanism of injury information encoding is unclear. Here, using ATP fluorescent indicators, we identify injury-evoked spatiotemporally selective ATP dynamics, Inflares, in adult mice of both sexes. Inflares are actively released from astrocytes and act as the internal representations of injury. Inflares encode injury intensity and position at their population level through frequency changes and are further decoded by microglia, driving changes in their activation state. Mismatches between Inflares and injury severity lead to microglia dysfunction and worsening of injury outcome. Blocking Inflares in ischemic stroke in mice reduces secondary damage and improves recovery of function. Our results suggest that astrocytic ATP dynamics encode injury information and are sensed by microglia.
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Affiliation(s)
- Yue Chen
- Chinese Institute for Brain Research, Beijing, China
| | - Pengwei Luan
- Chinese Institute for Brain Research, Beijing, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Juan Liu
- Chinese Institute for Brain Research, Beijing, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Yelan Wei
- Chinese Institute for Brain Research, Beijing, China
- Department of College of Physical Education and Sport, Beijing Normal University, Beijing, China
| | - Chenyu Wang
- Chinese Institute for Brain Research, Beijing, China
- Capital Medical University, Basic Medical Sciences, Beijing, China
| | - Rui Wu
- Chinese Institute for Brain Research, Beijing, China
- China Agricultural University, Beijing, China
| | - Zhaofa Wu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
- PKU-IDG/McGovern Institute for Brain Research, Beijing, China
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Miao Jing
- Chinese Institute for Brain Research, Beijing, China.
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2
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Liu Y, Chen L, Lin L, Xu C, Xiong Y, Qiu H, Li X, Li S, Cao H. Unveiling the hidden pathways: Exploring astrocytes as a key target for depression therapy. J Psychiatr Res 2024; 174:101-113. [PMID: 38626560 DOI: 10.1016/j.jpsychires.2024.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 03/07/2024] [Accepted: 04/02/2024] [Indexed: 04/18/2024]
Abstract
Depressive disorders are widely debilitating psychiatric disease. Despite the considerable progress in the field of depression therapy, extensive research spanning many decades has failed to uncover pathogenic pathways that might aid in the creation of long-acting and rapid-acting antidepressants. Consequently, it is imperative to reconsider existing approaches and explore other targets to improve this area of study. In contemporary times, several scholarly investigations have unveiled that persons who have received a diagnosis of depression, as well as animal models employed to study depression, demonstrate a decrease in both the quantity as well as density of astrocytes, accompanied by alterations in gene expression and morphological attributes. Astrocytes rely on a diverse array of channels and receptors to facilitate their neurotransmitter transmission inside tripartite synapses. This study aimed to investigate the potential processes behind the development of depression, specifically focusing on astrocyte-associated neuroinflammation and the involvement of several molecular components such as connexin 43, potassium channel Kir4.1, aquaporin 4, glutamatergic aspartic acid transporter protein, SLC1A2 or GLT-1, glucocorticoid receptors, 5-hydroxytryptamine receptor 2B, and autophagy, that localized on the surface of astrocytes. The study also explores novel approaches in the treatment of depression, with a focus on astrocytes, offering innovative perspectives on potential antidepressant medications.
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Affiliation(s)
- Ying Liu
- Department of Psychiatry, The School of Clinical Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China; Department of Psychiatry, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
| | - Lu Chen
- Department of Gastroenterology, The School of Clinical Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China; Department of Gastroenterology, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
| | - Lin Lin
- Scientific Research Management Department, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
| | - Caijuan Xu
- Department of Psychiatry, The School of Clinical Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China; Department of Psychiatry, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
| | - Yifan Xiong
- Department of Psychiatry, The School of Clinical Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China; Department of Psychiatry, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
| | - Huiwen Qiu
- Department of Psychiatry, The School of Clinical Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China; Department of Psychiatry, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
| | - Xinyu Li
- Department of Psychiatry, The School of Clinical Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China; Department of Psychiatry, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
| | - Sixin Li
- Department of Psychiatry, The School of Clinical Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China; Department of Psychiatry, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
| | - Hui Cao
- Department of Psychiatry, The School of Clinical Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China; Department of Psychiatry, Brain Hospital of Hunan Province (The Second People's Hospital of Hunan Province), Changsha, Hunan, 410007, China.
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3
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Mokhtari T, Irandoost E, Sheikhbahaei F. Stress, pain, anxiety, and depression in endometriosis-Targeting glial activation and inflammation. Int Immunopharmacol 2024; 132:111942. [PMID: 38565045 DOI: 10.1016/j.intimp.2024.111942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Revised: 03/24/2024] [Accepted: 03/25/2024] [Indexed: 04/04/2024]
Abstract
Endometriosis (EM) is a gynecological inflammatory disease often accompanied by stress, chronic pelvic pain (CPP), anxiety, and depression, leading to a diminished quality of life. This review aims to discuss the relationship between systemic and local inflammatory responses in the central nervous system (CNS), focusing on glial dysfunctions (astrocytes and microglia) as in critical brain regions involved in emotion, cognition, pain processing, anxiety, and depression. The review presents that EM is connected to increased levels of pro-inflammatory cytokines in the circulation. Additionally, chronic stress and CPP as stressors may contribute to the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, depleting the production of inflammatory mediators in the circulatory system and the brain. The systemic cytokines cause blood-brain barrier (BBB) breakdown, activate microglia in the brain, and lead to neuroinflammation. Furthermore, CPP may induce neuronal morphological alterations in critical regions through central sensitization and the activation of glial cells. The activation of glial cells, particularly the polarization of microglia, leads to the activation of the NLRP3 inflammasome and the overproduction of inflammatory cytokines. These inflammatory cytokines interact with the signaling pathways involved in neural plasticity. Additionally, persistent inflammatory conditions in the brain lead to neuronal death, which is correlated with a reduced volume of key brain regions such as the hippocampus. This review highlights the involvement of glial cells in the pathogenesis of the mental comorbidities of EM (i.e., pain, anxiety, and depression) and to discuss potential therapeutic approaches for targeting the inflammation and activation of microglia in key brain regions.
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Affiliation(s)
- Tahmineh Mokhtari
- Department of Pharmacology, Hubei University of Medicine, Shiyan, China; Department of Histology and Embryology, Faculty of Basic Medical Sciences, Hubei University of Medicine, Shiyan, China
| | - Elnaz Irandoost
- Sarem Women's Hospital, Iran University of Medical Sciences (IUMS), Tehran, Iran.
| | - Fatemeh Sheikhbahaei
- Department of Anatomy, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran.
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Chamaa F, Magistretti PJ, Fiumelli H. Astrocyte-derived lactate in stress disorders. Neurobiol Dis 2024; 192:106417. [PMID: 38296112 DOI: 10.1016/j.nbd.2024.106417] [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: 08/27/2023] [Revised: 12/04/2023] [Accepted: 01/23/2024] [Indexed: 02/05/2024] Open
Abstract
Stress disorders are psychiatric disorders arising following stressful or traumatic events. They could deleteriously affect an individual's health because they often co-occur with mental illnesses. Considerable attention has been focused on neurons when considering the neurobiology of stress disorders. However, like other mental health conditions, recent studies have highlighted the importance of astrocytes in the pathophysiology of stress-related disorders. In addition to their structural and homeostatic support role, astrocytes actively serve several functions in regulating synaptic transmission and plasticity, protecting neurons from toxic compounds, and providing metabolic support for neurons. The astrocyte-neuron lactate shuttle model sets forth the importance of astrocytes in providing lactate for the metabolic supply of neurons under intense activity. Lactate also plays a role as a signaling molecule and has been recently studied regarding its antidepressant activity. This review discusses the involvement of astrocytes and brain energy metabolism in stress and further reflects on the importance of lactate as an energy supply in the brain and its emerging antidepressant role in stress-related disorders.
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Affiliation(s)
- Farah Chamaa
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia
| | - Pierre J Magistretti
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia
| | - Hubert Fiumelli
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia.
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Gong L, Liang J, Xie L, Zhang Z, Mei Z, Zhang W. Metabolic Reprogramming in Gliocyte Post-cerebral Ischemia/ Reperfusion: From Pathophysiology to Therapeutic Potential. Curr Neuropharmacol 2024; 22:1672-1696. [PMID: 38362904 DOI: 10.2174/1570159x22666240131121032] [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: 08/21/2023] [Revised: 12/08/2023] [Accepted: 12/13/2023] [Indexed: 02/17/2024] Open
Abstract
Ischemic stroke is a leading cause of disability and death worldwide. However, the clinical efficacy of recanalization therapy as a preferred option is significantly hindered by reperfusion injury. The transformation between different phenotypes of gliocytes is closely associated with cerebral ischemia/ reperfusion injury (CI/RI). Moreover, gliocyte polarization induces metabolic reprogramming, which refers to the shift in gliocyte phenotype and the overall transformation of the metabolic network to compensate for energy demand and building block requirements during CI/RI caused by hypoxia, energy deficiency, and oxidative stress. Within microglia, the pro-inflammatory phenotype exhibits upregulated glycolysis, pentose phosphate pathway, fatty acid synthesis, and glutamine synthesis, whereas the anti-inflammatory phenotype demonstrates enhanced mitochondrial oxidative phosphorylation and fatty acid oxidation. Reactive astrocytes display increased glycolysis but impaired glycogenolysis and reduced glutamate uptake after CI/RI. There is mounting evidence suggesting that manipulation of energy metabolism homeostasis can induce microglial cells and astrocytes to switch from neurotoxic to neuroprotective phenotypes. A comprehensive understanding of underlying mechanisms and manipulation strategies targeting metabolic pathways could potentially enable gliocytes to be reprogrammed toward beneficial functions while opening new therapeutic avenues for CI/RI treatment. This review provides an overview of current insights into metabolic reprogramming mechanisms in microglia and astrocytes within the pathophysiological context of CI/RI, along with potential pharmacological targets. Herein, we emphasize the potential of metabolic reprogramming of gliocytes as a therapeutic target for CI/RI and aim to offer a novel perspective in the treatment of CI/RI.
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Affiliation(s)
- Lipeng Gong
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Junjie Liang
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Letian Xie
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Zhanwei Zhang
- Department of Neurosurgery, First Affiliated Hospital of Hunan University of Traditional Chinese Medicine, Changsha, Hunan 410007, China
| | - Zhigang Mei
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
- Third-Grade Pharmacological Laboratory on Chinese Medicine Approved by State Administration of Traditional Chinese Medicine, College of Medicine and Health Sciences, China Three Gorges University, Yichang, Hubei 443002, China
| | - Wenli Zhang
- School of Pharmacy, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
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Gonzalez H, Narasipura SD, Shull T, Shetty A, Teppen TL, Naqib A, Al-Harthi L. An Efficient and Cost-Effective Approach to Generate Functional Human Inducible Pluripotent Stem Cell-Derived Astrocytes. Cells 2023; 12:2357. [PMID: 37830571 PMCID: PMC10571578 DOI: 10.3390/cells12192357] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/11/2023] [Accepted: 09/16/2023] [Indexed: 10/14/2023] Open
Abstract
Human inducible pluripotent stem cell (hiPSC)-derived astrocytes (iAs) are critical to study astrocytes in health and disease. They provide several advantages over human fetal astrocytes in research, which include consistency, availability, disease modeling, customization, and ethical considerations. The generation of iAs is hampered by the requirement of Matrigel matrix coating for survival and proliferation. We provide a protocol demonstrating that human iAs cultured in the absence of Matrigel are viable and proliferative. Further, through a side-by-side comparison of cultures with and without Matrigel, we show significant similarities in astrocyte-specific profiling, including morphology (shape and structure), phenotype (cell-specific markers), genotype (transcriptional expression), metabolic (respiration), and functional aspects (glutamate uptake and cytokine response). In addition, we report that, unlike other CNS cell types, such as neuronal progenitor cells and neurons, iAs can withstand the absence of Matrigel coating. Our study demonstrates that Matrigel is dispensable for the culture of human iPSC-derived astrocytes, facilitating an easy, streamlined, and cost-effective method of generating these cells.
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Affiliation(s)
- Hemil Gonzalez
- Department of Internal Medicine, Division of Infectious Diseases, Rush University Medical Center, Chicago, IL 60612, USA
- Department of Microbial Pathogens and Immunity, Rush Medical College, Chicago, IL 60612, USA; (S.D.N.); (T.S.)
| | - Srinivas D. Narasipura
- Department of Microbial Pathogens and Immunity, Rush Medical College, Chicago, IL 60612, USA; (S.D.N.); (T.S.)
| | - Tanner Shull
- Department of Microbial Pathogens and Immunity, Rush Medical College, Chicago, IL 60612, USA; (S.D.N.); (T.S.)
- Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois, Chicago, IL 60608, USA
| | - Amogh Shetty
- Illinois Mathematics and Science Academy, Aurora, IL 60506, USA
| | - Tara L. Teppen
- Molecular Neurobiology Division, Rush Alzheimer’s Disease Center, Rush University, Chicago, IL 60612, USA
| | - Ankur Naqib
- Genome Core Facility, Rush University, Chicago, IL 60612, USA;
| | - Lena Al-Harthi
- Department of Microbial Pathogens and Immunity, Rush Medical College, Chicago, IL 60612, USA; (S.D.N.); (T.S.)
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Skiöldebrand E, Adepu S, Lützelschwab C, Nyström S, Lindahl A, Abrahamsson-Aurell K, Hansson E. A randomized, triple-blinded controlled clinical study with a novel disease-modifying drug combination in equine lameness-associated osteoarthritis. OSTEOARTHRITIS AND CARTILAGE OPEN 2023; 5:100381. [PMID: 37416846 PMCID: PMC10320210 DOI: 10.1016/j.ocarto.2023.100381] [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: 06/02/2023] [Revised: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 07/08/2023] Open
Abstract
Objective This study aimed to test a novel treatment combination (TC) (equivalent to sildenafil, mepivacaine, and glucose) with disease-modifying properties compared to Celestone® bifas® (CB) in a randomized triple-blinded phase III clinical study in horses with mild osteoarthritis (OA). Joint biomarkers (reflecting the articular cartilage and subchondral bone remodelling) and clinical lameness were used as readouts to evaluate the treatment efficacy. Methods Twenty horses with OA-associated lameness in the carpal joint were included in the study and received either TC (n = 10) or CB (n = 10) drug intra-articularly-twice in the middle carpal joint with an interval of 2 weeks (visit 1 & 2). Clinical lameness was assessed both objectively (Lameness locator) and subjectively (visually). Synovial fluid and serum were sampled for quantification of the extracellular matrix (ECM) neo-epitope joint biomarkers represented by biglycan (BGN262) and cartilage oligomeric matrix protein (COMP156). Another two weeks later clinical lameness was recorded, and serum was collected for biomarkers analysis. The overall health status was compared pre and post-intervention by interviewing the trainer. Results Post-intervention, SF BGN262 levels significantly declined in TC (P = 0.002) and COMP156 levels significantly increased in CB (P = 0.002). The flexion test scores improved in the TC compared to CB (P =0.033) and also had an improved trotting gait quality (P =0.044). No adverse events were reported. Conclusion This is the first clinical study presenting companion diagnostics assisting in identifying OA phenotype and evaluating the efficacy and safety of a novel disease-modifying osteoarthritic drug.
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Affiliation(s)
- E. Skiöldebrand
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - S. Adepu
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - C. Lützelschwab
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - S. Nyström
- Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska University Hospital, Gothenburg University, Gothenburg, Sweden
| | - A. Lindahl
- Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska University Hospital, Gothenburg University, Gothenburg, Sweden
| | - K. Abrahamsson-Aurell
- Hallands Djursjukhus Kungsbacka Hästklinik, Älvsåkers Byväg 20, 434 95 Kungsbacka, Sweden
| | - E. Hansson
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Mustafa S, Bajic JE, Barry B, Evans S, Siemens KR, Hutchinson MR, Grace PM. One immune system plays many parts: The dynamic role of the immune system in chronic pain and opioid pharmacology. Neuropharmacology 2023; 228:109459. [PMID: 36775098 PMCID: PMC10015343 DOI: 10.1016/j.neuropharm.2023.109459] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023]
Abstract
The transition from acute to chronic pain is an ongoing major problem for individuals, society and healthcare systems around the world. It is clear chronic pain is a complex multidimensional biological challenge plagued with difficulties in pain management, specifically opioid use. In recent years the role of the immune system in chronic pain and opioid pharmacology has come to the forefront. As a highly dynamic and versatile network of cells, tissues and organs, the immune system is perfectly positioned at the microscale level to alter nociception and drive structural adaptations that underpin chronic pain and opioid use. In this review, we highlight the need to understand the dynamic and adaptable characteristics of the immune system and their role in the transition, maintenance and resolution of chronic pain. The complex multidimensional interplay of the immune system with multiple physiological systems may provide new transformative insight for novel targets for clinical management and treatment of chronic pain. This article is part of the Special Issue on "Opioid-induced changes in addiction and pain circuits".
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Affiliation(s)
- Sanam Mustafa
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia; Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, The University of Adelaide, Adelaide, SA, Australia; Davies Livestock Research Centre, The University of Adelaide, Roseworthy, SA, Australia.
| | - Juliana E Bajic
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia; Davies Livestock Research Centre, The University of Adelaide, Roseworthy, SA, Australia
| | - Benjamin Barry
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia
| | - Samuel Evans
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia; Davies Livestock Research Centre, The University of Adelaide, Roseworthy, SA, Australia
| | - Kariel R Siemens
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia
| | - Mark R Hutchinson
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia; Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, The University of Adelaide, Adelaide, SA, Australia; Davies Livestock Research Centre, The University of Adelaide, Roseworthy, SA, Australia
| | - Peter M Grace
- Laboratories of Neuroimmunology, Department of Symptom Research, University of Texas MD Anderson Cancer Center, Houston, TX, USA; MD Anderson Pain Research Consortium, Houston, TX, USA
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Cheung G, Chever O, Rollenhagen A, Quenech'du N, Ezan P, Lübke JHR, Rouach N. Astroglial Connexin 43 Regulates Synaptic Vesicle Release at Hippocampal Synapses. Cells 2023; 12:cells12081133. [PMID: 37190042 DOI: 10.3390/cells12081133] [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: 02/17/2023] [Revised: 04/01/2023] [Accepted: 04/03/2023] [Indexed: 05/17/2023] Open
Abstract
Connexin 43, an astroglial gap junction protein, is enriched in perisynaptic astroglial processes and plays major roles in synaptic transmission. We have previously found that astroglial Cx43 controls synaptic glutamate levels and allows for activity-dependent glutamine release to sustain physiological synaptic transmissions and cognitiogns. However, whether Cx43 is important for the release of synaptic vesicles, which is a critical component of synaptic efficacy, remains unanswered. Here, using transgenic mice with a glial conditional knockout of Cx43 (Cx43-/-), we investigate whether and how astrocytes regulate the release of synaptic vesicles from hippocampal synapses. We report that CA1 pyramidal neurons and their synapses develop normally in the absence of astroglial Cx43. However, a significant impairment in synaptic vesicle distribution and release dynamics were observed. In particular, the FM1-43 assays performed using two-photon live imaging and combined with multi-electrode array stimulation in acute hippocampal slices, revealed a slower rate of synaptic vesicle release in Cx43-/- mice. Furthermore, paired-pulse recordings showed that synaptic vesicle release probability was also reduced and is dependent on glutamine supply via Cx43 hemichannel (HC). Taken together, we have uncovered a role for Cx43 in regulating presynaptic functions by controlling the rate and probability of synaptic vesicle release. Our findings further highlight the significance of astroglial Cx43 in synaptic transmission and efficacy.
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Affiliation(s)
- Giselle Cheung
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| | - Oana Chever
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| | - Astrid Rollenhagen
- Institute for Neuroscience and Medicine INM-10, Research Center Jülich, 52428 Jülich, Germany
- Jülich-Aachen Research Alliance Translational Brain Medicine, 52056 Aachen, Germany
| | - Nicole Quenech'du
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| | - Pascal Ezan
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
| | - Joachim H R Lübke
- Institute for Neuroscience and Medicine INM-10, Research Center Jülich, 52428 Jülich, Germany
- Jülich-Aachen Research Alliance Translational Brain Medicine, 52056 Aachen, Germany
- Department of Psychiatry, Psychotherapy and Psychosomatics, Rheinisch-Westfaelische Technische Hochschule Aachen University, 52056 Aachen, Germany
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, 75231 Paris, France
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10
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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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11
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Xu J, Li P, Lu F, Chen Y, Guo Q, Yang Y. Domino reaction of neurovascular unit in neuropathic pain after spinal cord injury. Exp Neurol 2023; 359:114273. [PMID: 36375510 DOI: 10.1016/j.expneurol.2022.114273] [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: 08/22/2022] [Revised: 10/25/2022] [Accepted: 11/08/2022] [Indexed: 11/12/2022]
Abstract
The mechanism of neuropathic pain after spinal cord injury is complex, and the communication between neurons, glia, and blood vessels in neurovascular units significantly affects the occurrence and development of neuropathic pain. After spinal cord injury, a domino chain reaction occurs in the neuron-glia-vessel, which affects the permeability of the blood-spinal cord barrier and jointly promotes the development of neuroinflammation. This article discusses the signal transduction between neuro-glial-endothelial networks from a multidimensional point of view and reviews its role in neuropathic pain after spinal cord injury.
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Affiliation(s)
- Jingmei Xu
- Department of Anesthesiology, Xiangya Hospital, Central South University, 87th Xiangya Road, Kaifu District, Changsha, Hunan, China
| | - Ping Li
- National Clinical Research Center for Geriatric Disorders,Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Department of Obstetrics, Xiangya Hospital, Central South University, 87th Xiangya Road, Kaifu District, Changsha, Hunan, China
| | - Feng Lu
- Department of Anesthesiology, First Affiliated Hospital of Gannan medical university, Ganzhou 341000, China
| | - Yulu Chen
- Department of Anesthesiology, Xiangya Hospital, Central South University, 87th Xiangya Road, Kaifu District, Changsha, Hunan, China
| | - Qulian Guo
- Department of Anesthesiology, Xiangya Hospital, Central South University, 87th Xiangya Road, Kaifu District, Changsha, Hunan, China; National Clinical Research Center for Geriatric Disorders,Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China
| | - Yong Yang
- Department of Anesthesiology, Xiangya Hospital, Central South University, 87th Xiangya Road, Kaifu District, Changsha, Hunan, China; National Clinical Research Center for Geriatric Disorders,Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China.
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12
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Yang H, Tenorio Lopes L, Barioni NO, Roeske J, Incognito AV, Baker J, Raj SR, Wilson RJA. The molecular makeup of peripheral and central baroreceptors: stretching a role for Transient Receptor Potential (TRP), Epithelial Sodium Channel (ENaC), Acid Sensing Ion Channel (ASIC), and Piezo channels. Cardiovasc Res 2022; 118:3052-3070. [PMID: 34734981 DOI: 10.1093/cvr/cvab334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 09/27/2021] [Accepted: 10/29/2021] [Indexed: 12/16/2022] Open
Abstract
The autonomic nervous system maintains homeostasis of cardiovascular, respiratory, gastrointestinal, urinary, immune, and thermoregulatory function. Homeostasis involves a variety of feedback mechanisms involving peripheral afferents, many of which contain molecular receptors sensitive to mechanical deformation, termed mechanosensors. Here, we focus on the molecular identity of mechanosensors involved in the baroreflex control of the cardiovascular system. Located within the walls of the aortic arch and carotid sinuses, and/or astrocytes in the brain, these mechanosensors are essential for the rapid moment-to-moment feedback regulation of blood pressure (BP). Growing evidence suggests that these mechanosensors form a co-existing system of peripheral and central baroreflexes. Despite the importance of these molecules in cardiovascular disease and decades of research, their precise molecular identity remains elusive. The uncertainty surrounding the identity of these mechanosensors presents a major challenge in understanding basic baroreceptor function and has hindered the development of novel therapeutic targets for conditions with known arterial baroreflex impairments. Therefore, the purpose of this review is to (i) provide a brief overview of arterial and central baroreflex control of BP, (ii) review classes of ion channels currently proposed as the baroreflex mechanosensor, namely Transient Receptor Potential (TRP), Epithelial Sodium Channel (ENaC), Acid Sensing Ion Channel (ASIC), and Piezo, along with additional molecular candidates that serve mechanotransduction in other organ systems, and (iii) summarize the potential clinical implications of impaired baroreceptor function in the pathophysiology of cardiovascular disease.
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Affiliation(s)
- Hannah Yang
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada
| | - Luana Tenorio Lopes
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada
| | - Nicole O Barioni
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada
| | - Jamie Roeske
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada
| | - Anthony V Incognito
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada
| | - Jacquie Baker
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada
| | - Satish R Raj
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada
| | - Richard J A Wilson
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada.,Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. N.W., Calgary, AB T2N4N1, Canada
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13
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Rangel B, Mesentier-Louro LA, Lowe LL, Shariati AM, Dalal R, Imventarza JA, Liao YJ. Upregulation of retinal VEGF and connexin 43 in murine nonarteritic anterior ischemic optic neuropathy induced with 577 nm laser. Exp Eye Res 2022; 225:109139. [PMID: 35691373 PMCID: PMC10870834 DOI: 10.1016/j.exer.2022.109139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/08/2022] [Accepted: 06/01/2022] [Indexed: 12/29/2022]
Abstract
Nonarteritic anterior ischemic optic neuropathy (NAION) is a common acute optic neuropathy and cause of irreversible vision loss in those older than 50 years of age. There is currently no effective treatment for NAION and the biological mechanisms leading to neuronal loss are not fully understood. Promising novel targets include glial cells activation and intercellular communication mediated by molecules such as gap junction protein Connexin 43 (Cx43), which modulate neuronal fate in central nervous system disorders. In this study, we investigated retinal glial changes and neuronal loss following a novel NAION animal model using a 577 nm yellow laser. We induced unilateral photochemical thrombosis using rose bengal at the optic nerve head vasculature in adult C57BL/6 mice using a 577 nm laser and performed morphometric analysis of the retinal structure using serial in vivo optical coherence tomography (OCT) and histology for glial and neuronal markers. One day after experimental NAION, in acute phase, OCT imaging revealed peripapillary thickening of the retinal ganglion cell complex (GCC, baseline: 79.5 ± 1.0 μm, n = 8; NAION: 93.0 ± 2.5 μm, n = 8, P < 0.01) and total retina (baseline: 202.9 ± 2.4 μm, n = 8; NAION: 228.1 ± 6.8 μm, n = 8, P < 0.01). Twenty-one days after ischemia, at a chronic phase, there was significant GCC thinning (baseline 78.3 ± 2.1 μm, n = 6; NAION: 72.2 ± 1.9 μm, n = 5, P < 0.05), mimicking human disease. Examination of molecular changes in the retina one day after ischemia revealed that NAION induced a significant increase in retinal VEGF levels (control: 2319 ± 195, n = 5; NAION: 4549 ± 683 gray mean value, n = 5, P < 0.05), which highly correlated with retinal thickness (r = 0.89, P < 0.05). NAION also led to significant increase in mRNA level for Cx43 (Gj1a) at day 1 (control: 1.291 ± 0.38; NAION: 3.360 ± 0.58 puncta/mm2, n = 5, P < 0.05), but not of glial fibrillary acidic protein (Gfap) at the same time (control: 2,800 ± 0.59; NAION: 4,690 ± 0.90 puncta/mm2 n = 5, P = 0.19). Retinal ganglion cell loss at day 21 was confirmed by a 30% decrease in Brn3a+ cells (control: 2,844 ± 235; NAION: 2,001 ± 264 cells/mm2, n = 4, P < 0.05). We described a novel protocol of NAION induction by photochemical thrombosis using a 577 nm laser, leading to retinal edema and VEGF increase at day 1 and RGCs loss at day 21 after injury, consistent with the pathophysiology of human NAION. Early changes in glial cells intercommunication revealed by increased Cx43+ gap junctions are consistent with a retinal glial role in mediating cell-to-cell signaling after an ischemic insult. Our study demonstrates an early glial response in a novel NAION animal model and reveals glial intercommunication molecules such as Cx43 as a promising therapeutic target in acute NAION.
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Affiliation(s)
- Barbara Rangel
- Department of Ophthalmology, Stanford University School of Medicine, Stanford, CA, 94303, USA
| | | | - Lauryn L Lowe
- Department of Ophthalmology, Stanford University School of Medicine, Stanford, CA, 94303, USA
| | - Ali Mohammad Shariati
- Department of Ophthalmology, Stanford University School of Medicine, Stanford, CA, 94303, USA
| | - Roopa Dalal
- Department of Ophthalmology, Stanford University School of Medicine, Stanford, CA, 94303, USA
| | - Joel A Imventarza
- Department of Ophthalmology, Stanford University School of Medicine, Stanford, CA, 94303, USA
| | - Yaping Joyce Liao
- Department of Ophthalmology, Stanford University School of Medicine, Stanford, CA, 94303, USA; Department of Neurology, Stanford University School of Medicine, Stanford, CA, 94304, USA.
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14
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Aghighi Z, Ghorbani Z, Moghaddam MH, Fathi M, Abdollahifar MA, Soleimani M, Karimzadeh F, Rasoolijazi H, Aliaghaei A. Melittin ameliorates motor function and prevents autophagy-induced cell death and astrogliosis in rat models of cerebellar ataxia induced by 3-acetylpyridine. Neuropeptides 2022; 96:102295. [PMID: 36280441 DOI: 10.1016/j.npep.2022.102295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022]
Abstract
BACKGROUND Cerebellar ataxia (CA) is a form of ataxia that adversely affects the cerebellum. This study aims to investigate the therapeutic effects of melittin (MEL) on a 3-acetylpyridine-induced (3-AP) cerebellar ataxia (CA) rat model. METHODS Initially, CA rat models were generated by 3-AP administration followed by the subcutaneous injection of MEL. The open-field test was used for the evaluation of locomotion and anxiety. Immunohistochemistry was also conducted for the autophagy markers of LC3 and Beclin1. In the next step, the morphology of the astrocyte, the cell responsible for maintaining homeostasis in the CNS, was evaluated by the Sholl analysis. RESULTS The findings suggested that the administration of MEL in a 3-AP model of ataxia improved locomotion and anxiety (P < 0.001), decreased the expression of LC3 (P < 0.01) and Beclin1 (P < 0.05), increased astrocyte complexity (P < 0.05) and reduced astrocyte cell soma size (P < 0.001). CONCLUSIONS Overall, the findings imply that the MEL attenuates the 3-AP-induced autophagy, causes cell death and improves motor function. As such, it could be used as a therapeutic procedure for CA due to its neuroprotective effects.
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Affiliation(s)
- Zahra Aghighi
- Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Zeynab Ghorbani
- Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Meysam Hassani Moghaddam
- Department of Anatomical Sciences, Faculty of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Mobina Fathi
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad-Amin Abdollahifar
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mansoureh Soleimani
- Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Fariba Karimzadeh
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Homa Rasoolijazi
- Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Abbas Aliaghaei
- Hearing Disorders Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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15
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Cheng T, Xu Z, Ma X. The role of astrocytes in neuropathic pain. Front Mol Neurosci 2022; 15:1007889. [PMID: 36204142 PMCID: PMC9530148 DOI: 10.3389/fnmol.2022.1007889] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 08/30/2022] [Indexed: 11/23/2022] Open
Abstract
Neuropathic pain, whose symptoms are characterized by spontaneous and irritation-induced painful sensations, is a condition that poses a global burden. Numerous neurotransmitters and other chemicals play a role in the emergence and maintenance of neuropathic pain, which is strongly correlated with common clinical challenges, such as chronic pain and depression. However, the mechanism underlying its occurrence and development has not yet been fully elucidated, thus rendering the use of traditional painkillers, such as non-steroidal anti-inflammatory medications and opioids, relatively ineffective in its treatment. Astrocytes, which are abundant and occupy the largest volume in the central nervous system, contribute to physiological and pathological situations. In recent years, an increasing number of researchers have claimed that astrocytes contribute indispensably to the occurrence and progression of neuropathic pain. The activation of reactive astrocytes involves a variety of signal transduction mechanisms and molecules. Signal molecules in cells, including intracellular kinases, channels, receptors, and transcription factors, tend to play a role in regulating post-injury pain once they exhibit pathological changes. In addition, astrocytes regulate neuropathic pain by releasing a series of mediators of different molecular weights, actively participating in the regulation of neurons and synapses, which are associated with the onset and general maintenance of neuropathic pain. This review summarizes the progress made in elucidating the mechanism underlying the involvement of astrocytes in neuropathic pain regulation.
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16
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Fatoyinbo HO, Brown RG, Simpson DJW, van Brunt B. Pattern Formation in a Spatially Extended Model of Pacemaker Dynamics in Smooth Muscle Cells. Bull Math Biol 2022; 84:86. [PMID: 35804271 PMCID: PMC9270316 DOI: 10.1007/s11538-022-01043-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 06/16/2022] [Indexed: 11/30/2022]
Abstract
Spatiotemporal patterns are common in biological systems. For electrically coupled cells, previous studies of pattern formation have mainly used applied current as the primary bifurcation parameter. The purpose of this paper is to show that applied current is not needed to generate spatiotemporal patterns for smooth muscle cells. The patterns can be generated solely by external mechanical stimulation (transmural pressure). To do this we study a reaction-diffusion system involving the Morris-Lecar equations and observe a wide range of spatiotemporal patterns for different values of the model parameters. Some aspects of these patterns are explained via a bifurcation analysis of the system without coupling - in particular Type I and Type II excitability both occur. We show the patterns are not due to a Turing instability and that the spatially extended model exhibits spatiotemporal chaos. We also use travelling wave coordinates to analyse travelling waves.
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Affiliation(s)
- H O Fatoyinbo
- School of Mathematical and Computational Sciences, Massey University, Palmerston North, New Zealand.
| | - R G Brown
- School of Mathematical and Computational Sciences, Massey University, Palmerston North, New Zealand
| | - D J W Simpson
- School of Mathematical and Computational Sciences, Massey University, Palmerston North, New Zealand
| | - B van Brunt
- School of Mathematical and Computational Sciences, Massey University, Palmerston North, New Zealand
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17
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CXCR4/CX43 Regulate Diabetic Neuropathic Pain via Intercellular Interactions between Activated Neurons and Dysfunctional Astrocytes during Late Phase of Diabetes in Rats and the Effects of Antioxidant N-Acetyl-L-Cysteine. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:8547563. [PMID: 35799894 PMCID: PMC9256426 DOI: 10.1155/2022/8547563] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 06/15/2022] [Indexed: 12/12/2022]
Abstract
Growing evidence suggests that the interactions between astrocytes and neurons exert important functions in the central sensitization of the spinal cord dorsal horn in rodents with diabetes and neuropathic pain (DNP). However, it still remains unclear how signal transmission occurs in the spinal cord dorsal horn between astrocytes and neurons, especially in subjects with DNP. Chemokine CXC receptor 4 (CXCR4) plays critical roles in DNP, and connexin 43 (CX43), which is also primarily expressed by astrocytes, contributes to the development of neuropathy. We thus postulated that astrocytic and neuronal CXCR4 induces and produces inflammatory factors under persistent peripheral noxious stimulation in DNP, while intercellular CX43 can transmit inflammatory stimulation signals. The results showed that streptozotocin-induced type 1 diabetic rats developed heat hyperalgesia and mechanical allodynia. Diabetes led to persistent neuropathic pain. Diabetic rats developed peripheral sensitization at the early phase (2 weeks) and central sensitization at the late phase (5 weeks) after diabetes induction. Both CXCR4 and CX43, which are localized and coexpressed in neurons and astrocytes, were enhanced significantly in the dorsal horn of spinal cord in rats undergoing DNP during late phase of diabetes, and the CXCR4 antagonist AMD3100 reduced the expression of CX43. The nociceptive behavior was reversed, respectively, by AMD3100 at the early phase and by the antioxidant N-acetyl-L-cysteine (NAC) at the late phase. Furthermore, rats with DNP demonstrated downregulation of glial fibrillary acidic protein (GFAP) as well as upregulation of c-fos in the spinal cord dorsal horn at the late phase compared to the controls, and upregulation of GFAP and downregulation of c-fos were observed upon treatment with NAC. Given that GFAP and c-fos are, respectively, makers of astrocyte and neuronal activation, our findings suggest that CXCR4 as an inflammatory stimulation protein and CX43 as an intercellular signal transmission protein both may induce neurons excitability and astrocytes dysfunction in developing DNP.
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18
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Miguel-Hidalgo JJ. Astroglia in the Vulnerability to and Maintenance of Stress-Mediated Neuropathology and Depression. Front Cell Neurosci 2022; 16:869779. [PMID: 35530179 PMCID: PMC9074831 DOI: 10.3389/fncel.2022.869779] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 04/01/2022] [Indexed: 12/28/2022] Open
Abstract
Significant stress exposure and psychiatric depression are associated with morphological, biochemical, and physiological disturbances of astrocytes in specific brain regions relevant to the pathophysiology of those disorders, suggesting that astrocytes are involved in the mechanisms underlying the vulnerability to or maintenance of stress-related neuropathology and depression. To understand those mechanisms a variety of studies have probed the effect of various modalities of stress exposure on the metabolism, gene expression and plasticity of astrocytes. These studies have uncovered the participation of various cellular pathways, such as those for intracellular calcium regulation, neuroimmune responses, extracellular ionic regulation, gap junctions-based cellular communication, and regulation of neurotransmitter and gliotransmitter release and uptake. More recently epigenetic modifications resulting from exposure to chronic forms of stress or to early life adversity have been suggested to affect not only neuronal mechanisms but also gene expression and physiology of astrocytes and other glial cells. However, much remains to be learned to understand the specific role of those and other modifications in the astroglial contribution to the vulnerability to and maintenance of stress-related disorders and depression, and for leveraging that knowledge to achieve more effective psychiatric therapies.
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Fang X, Wang H, Zhuo Z, Tian P, Chen Z, Wang Y, Cheng X. miR-141-3p inhibits the activation of astrocytes and the release of inflammatory cytokines in bacterial meningitis through down-regulating HMGB1. Brain Res 2021; 1770:147611. [PMID: 34403663 DOI: 10.1016/j.brainres.2021.147611] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 07/13/2021] [Accepted: 08/06/2021] [Indexed: 12/22/2022]
Abstract
BACKGROUND Bacterial meningitis (BM) is a serious infectious disease of the central nervous system that often occurs in children and adolescents. Many studies have suggested that microRNAs (miRNAs) are involved in BM. This study aimed to address the effects of miR-141-3p on astrocyte activation and inflammatory response in BM through HMGB1. METHODS The 3-week-old rats were injected with Streptococcus pneumoniae (SP) into the lateral ventricle to establish a BM model. Loeffler scoring method was used to evaluate the recovery of neurological function. Brain pathological damage was observed by hematoxylin and eosin (H&E) staining. Primary astrocytes were isolated from brain tissues of BM or non-infected SD rats. The levels of TNF-α, IL-1β, and IL-6 in brain tissues and astrocyte culture supernatant were measured by enzyme-linked immunosorbent assay (ELISA). The targeting relationship between miR-141-3p and HMGB1 was tested using dual-luciferase reporter assay. The expression of miR-141-3p, HMGB1, and the astrocytic marker glial fibrillary acidic protein (GFAP) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blotting. Methylation-specific PCR (MSP) analysis was performed to measure the methylation status of miR-141 promoter. RESULTS The results showed that lower Loeffler scores were exhibited in rats with BM. The subarachnoid space of brain tissues of BM rats was widened, and obvious inflammatory cells were observed. miR-141-3p expression was reduced in BM rats and SP-treated astrocytes. Additionally, we found that overexpression of miR-141-3p led to the downregulation of HMGB1, GFAP, and inflammatory cytokines (TNF-α, IL-1β, and IL-6) in astrocytes. Furthermore, the results of dual-luciferase reporter assay confirmed that miR-141-3p directly targeted HMGB1. Overexpression of miR-141-3p inhibited the levels of GFAP, TNF-α, IL-1β, and IL-6 in astrocytes, which was eliminated by the up-regulation of HMGB1. The results of MSP analysis indicated that miR-141 promoter was highly methylated in brain tissues and astrocytes. DNMT1 was involved in the methylation of miR-141 promoter in BM. CONCLUSION The present study verified that miR-141-3p affected inflammatory response by suppressing HMGB1 in SP-induced astrocytes and BM rat model.
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Affiliation(s)
- Xiao Fang
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Huaili Wang
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Zhihong Zhuo
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Peichao Tian
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Zheng Chen
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Yue Wang
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Xiuyong Cheng
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
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20
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Lim EY, Ye L, Paukert M. Potential and Realized Impact of Astroglia Ca 2 + Dynamics on Circuit Function and Behavior. Front Cell Neurosci 2021; 15:682888. [PMID: 34163330 PMCID: PMC8215280 DOI: 10.3389/fncel.2021.682888] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/03/2021] [Indexed: 11/13/2022] Open
Abstract
Astroglia display a wide range of spontaneous and behavioral state-dependent Ca2+ dynamics. During heightened vigilance, noradrenergic signaling leads to quasi-synchronous Ca2+ elevations encompassing soma and processes across the brain-wide astroglia network. Distinct from this vigilance-associated global Ca2+ rise are apparently spontaneous fluctuations within spatially restricted microdomains. Over the years, several strategies have been pursued to shed light on the physiological impact of these signals including deletion of endogenous ion channels or receptors and reduction of intracellular Ca2+ through buffering, extrusion or inhibition of release. Some experiments that revealed the most compelling behavioral alterations employed chemogenetic and optogenetic manipulations to modify astroglia Ca2+ signaling. However, there is considerable contrast between these findings and the comparatively modest effects of inhibiting endogenous sources of Ca2+. In this review, we describe the underlying mechanisms of various forms of astroglia Ca2+ signaling as well as the functional consequences of their inhibition. We then discuss how the effects of exogenous astroglia Ca2+ modification combined with our knowledge of physiological mechanisms of astroglia Ca2+ activation could guide further refinement of behavioral paradigms that will help elucidate the natural Ca2+-dependent function of astroglia.
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Affiliation(s)
- Eunice Y. Lim
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States,Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Liang Ye
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Martin Paukert
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States,Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States,*Correspondence: Martin Paukert,
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21
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Omega-3 PUFAs Suppress IL-1β-Induced Hyperactivity of Immunoproteasomes in Astrocytes. Int J Mol Sci 2021; 22:ijms22115410. [PMID: 34063751 PMCID: PMC8196670 DOI: 10.3390/ijms22115410] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/16/2021] [Accepted: 05/19/2021] [Indexed: 12/14/2022] Open
Abstract
The role of immunoproteasome (iP) in astroglia, the cellular component of innate immunity, has not been clarified. The results so far indicate that neuroinflammation, a prominent hallmark of Alzheimer’s disease, strongly activates the iP subunits expression. Since omega-3 PUFAs possess anti-inflammatory and pro-resolving activity in the brain, we investigated the effect of DHA and EPA on the gene expression of constitutive (β1 and β5) and inducible (iβ1/LMP2 and iβ5/LMP7) proteasome subunits and proteasomal activity in IL-1β-stimulated astrocytes. We found that both PUFAs downregulated the expression of IL-1β-induced the iP subunits, but not the constitutive proteasome subunits. The chymotrypsin-like activity was inhibited in a dose-dependent manner by DHA, and much strongly in the lower concentration by EPA. Furthermore, we established that C/EBPα and C/EBPβ transcription factors, being the cis-regulatory element of the transcription complex, frequently activated by inflammatory mediators, participate in a reduction in the iP subunits’ expression. Moreover, the expression of connexin 43 the major gap junction protein in astrocytes, negatively regulated by IL-1β was markedly increased in PUFA-treated cells. These findings indicate that omega-3 PUFAs attenuate inflammation-induced hyperactivity of iPs in astrocytes and have a beneficial effect on preservation of interastrocytic communication by gap junctions.
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22
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Mesnil M, Defamie N, Naus C, Sarrouilhe D. Brain Disorders and Chemical Pollutants: A Gap Junction Link? Biomolecules 2020; 11:51. [PMID: 33396565 PMCID: PMC7824109 DOI: 10.3390/biom11010051] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 02/07/2023] Open
Abstract
The incidence of brain pathologies has increased during last decades. Better diagnosis (autism spectrum disorders) and longer life expectancy (Parkinson's disease, Alzheimer's disease) partly explain this increase, while emerging data suggest pollutant exposures as a possible but still underestimated cause of major brain disorders. Taking into account that the brain parenchyma is rich in gap junctions and that most pollutants inhibit their function; brain disorders might be the consequence of gap-junctional alterations due to long-term exposures to pollutants. In this article, this hypothesis is addressed through three complementary aspects: (1) the gap-junctional organization and connexin expression in brain parenchyma and their function; (2) the effect of major pollutants (pesticides, bisphenol A, phthalates, heavy metals, airborne particles, etc.) on gap-junctional and connexin functions; (3) a description of the major brain disorders categorized as neurodevelopmental (autism spectrum disorders, attention deficit hyperactivity disorders, epilepsy), neurobehavioral (migraines, major depressive disorders), neurodegenerative (Parkinson's and Alzheimer's diseases) and cancers (glioma), in which both connexin dysfunction and pollutant involvement have been described. Based on these different aspects, the possible involvement of pollutant-inhibited gap junctions in brain disorders is discussed for prenatal and postnatal exposures.
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Affiliation(s)
- Marc Mesnil
- Laboratoire STIM, ERL7003 CNRS-Université de Poitiers, 1 rue G. Bonnet–TSA 51 106, 86073 Poitiers, France; (M.M.); (N.D.)
| | - Norah Defamie
- Laboratoire STIM, ERL7003 CNRS-Université de Poitiers, 1 rue G. Bonnet–TSA 51 106, 86073 Poitiers, France; (M.M.); (N.D.)
| | - Christian Naus
- Faculty of Medicine, Department of Cellular & Physiological Sciences, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T1Z3, Canada;
| | - Denis Sarrouilhe
- Laboratoire de Physiologie Humaine, Faculté de Médecine et Pharmacie, 6 rue de La Milétrie, bât D1, TSA 51115, 86073 Poitiers, France
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23
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Donnelly CR, Andriessen AS, Chen G, Wang K, Jiang C, Maixner W, Ji RR. Central Nervous System Targets: Glial Cell Mechanisms in Chronic Pain. Neurotherapeutics 2020; 17:846-860. [PMID: 32820378 PMCID: PMC7609632 DOI: 10.1007/s13311-020-00905-7] [Citation(s) in RCA: 133] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Interactions between central glial cells and neurons in the pain circuitry are critical contributors to the pathogenesis of chronic pain. In the central nervous system (CNS), two major glial cell types predominate: astrocytes and microglia. Injuries or pathological conditions which evoke pain are concurrently associated with the presence of a reactive microglia or astrocyte state, which is characterized by a variety of changes in the morphological, molecular, and functional properties of these cells. In this review, we highlight the changes that reactive microglia and astrocytes undergo following painful injuries and insults and discuss the critical and interactive role these two cell types play in the initiation and maintenance of chronic pain. Additionally, we focus on several crucial mechanisms by which microglia and astrocytes contribute to chronic pain and provide commentary on the therapeutic promise of targeting these pathways. In particular, we discuss how the inflammasome in activated microglia drives maturation and release of key pro-inflammatory cytokines, which drive pain through neuronal- and glial regulations. Moreover, we highlight several potentially-druggable hemichannels and proteases produced by reactive microglia and astrocytes in pain states and discuss how these pathways regulate distinct phases during pain pathogenesis. We also review two emerging areas in chronic pain research: 1) sexually dimorphic glial cell signaling and 2) the role of oligodendrocytes. Finally, we highlight important considerations for potential pain therapeutics targeting glial cell mediators as well as questions that remain in our conceptual understanding of glial cell activation in pain states.
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Affiliation(s)
- Christopher R Donnelly
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC, 27710, USA.
| | - Amanda S Andriessen
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Gang Chen
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Kaiyuan Wang
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Changyu Jiang
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - William Maixner
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Ru-Rong Ji
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC, 27710, USA.
- Department of Neurobiology, Duke University Medical Center, Durham, NC, 27710, USA.
- Department of Cell Biology, Duke University Medical Center, Durham, NC, 27710, USA.
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24
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Limanjaya I, Hsu TI, Chuang JY, Kao TJ. L-selectin activation regulates Rho GTPase activity via Ca +2 influx in Sertoli cell line, ASC-17D cells. Biochem Biophys Res Commun 2020; 525:1011-1017. [PMID: 32178872 DOI: 10.1016/j.bbrc.2020.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 03/03/2020] [Indexed: 12/31/2022]
Abstract
In seminiferous epithelium, tight junctions (TJs) between adjacent Sertoli cells constitute the blood-testis barrier and must change synchronically for germ cells to translocate from the basal to the adluminal compartment during the spermatogenic cycle. Rho GTPase activation through stimulation with specific L-selectin ligands has been proposed to modulate tight junctional dynamics. However, little is known regarding the role of Ca+2 dynamics in Sertoli cell and how Ca+2 relays L-selectin signals to modulate Rho GTPase activity in Sertoli cells, thus prompting us to investigate the Ca+2 flux induced by L-selectin ligand in ASC-17D cells. Using fluorescent real-time image, we first demonstrated the increase of intracellular Ca+2 level following L-selectin ligand stimulation. This Ca+2 increase was inhibited in ASC-17D cells pretreated with nifedipine, the L-type voltage-operated Ca+2 channel (VOCC) blocker, but not mibefradil, the T-type VOCC blocker. We then demonstrated the up-regulation of Rho and Rac1 in ASC-17D cells following the administration of L-selectin ligand, and the pre-treatment with nifedipine, but not mibefradil, prior to L-selectin ligand-binding abolished the activation of both Rho and Rac1. Together, we conclude that the activation of L-selectin induces Ca+2 influx through the L-type VOCC, which up-regulates Rho and Rac1 proteins, in ASC-17D cells.
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Affiliation(s)
- Ivan Limanjaya
- College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Tsung-I Hsu
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan; College of Medical Science and Technology, Taipei Medical University and National Health Research Institutes, Taipei, Taiwan; Research Center of Neuroscience, Taipei Medical University, Taipei, Taiwan; TMU Research Center of Cancer Translational Medicine, Taipei Medical University, Taipei, Taiwan
| | - Jian-Ying Chuang
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan; College of Medical Science and Technology, Taipei Medical University and National Health Research Institutes, Taipei, Taiwan; Research Center of Neuroscience, Taipei Medical University, Taipei, Taiwan; TMU Research Center of Cancer Translational Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Tzu-Jen Kao
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan; College of Medical Science and Technology, Taipei Medical University and National Health Research Institutes, Taipei, Taiwan; Research Center of Neuroscience, Taipei Medical University, Taipei, Taiwan; TMU Research Center of Cancer Translational Medicine, Taipei Medical University, Taipei, Taiwan.
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25
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Giaume C, Naus CC, Sáez JC, Leybaert L. Glial Connexins and Pannexins in the Healthy and Diseased Brain. Physiol Rev 2020; 101:93-145. [PMID: 32326824 DOI: 10.1152/physrev.00043.2018] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Over the past several decades a large amount of data have established that glial cells, the main cell population in the brain, dynamically interact with neurons and thus impact their activity and survival. One typical feature of glia is their marked expression of several connexins, the membrane proteins forming intercellular gap junction channels and hemichannels. Pannexins, which have a tetraspan membrane topology as connexins, are also detected in glial cells. Here, we review the evidence that connexin and pannexin channels are actively involved in dynamic and metabolic neuroglial interactions in physiological as well as in pathological situations. These features of neuroglial interactions open the way to identify novel non-neuronal aspects that allow for a better understanding of behavior and information processing performed by neurons. This will also complement the "neurocentric" view by facilitating the development of glia-targeted therapeutic strategies in brain disease.
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Affiliation(s)
- Christian Giaume
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France; University Pierre et Marie Curie, Paris, France; MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France; Department of Cellular & Physiological Sciences, Life Sciences Institute, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; Departamento de Fisiología, Pontificia Universidad Católica de Chile, Santiago, Chile; Instituo de Neurociencias, Centro Interdisciplinario de Neurociencias, Universidad de Valparaíso, Valparaíso, Chile; Physiology Group, Department of Basic and Applied Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Christian C Naus
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France; University Pierre et Marie Curie, Paris, France; MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France; Department of Cellular & Physiological Sciences, Life Sciences Institute, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; Departamento de Fisiología, Pontificia Universidad Católica de Chile, Santiago, Chile; Instituo de Neurociencias, Centro Interdisciplinario de Neurociencias, Universidad de Valparaíso, Valparaíso, Chile; Physiology Group, Department of Basic and Applied Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Juan C Sáez
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France; University Pierre et Marie Curie, Paris, France; MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France; Department of Cellular & Physiological Sciences, Life Sciences Institute, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; Departamento de Fisiología, Pontificia Universidad Católica de Chile, Santiago, Chile; Instituo de Neurociencias, Centro Interdisciplinario de Neurociencias, Universidad de Valparaíso, Valparaíso, Chile; Physiology Group, Department of Basic and Applied Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Luc Leybaert
- Collège de France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241/Institut National de la Santé et de la Recherche Médicale U1050, Paris, France; University Pierre et Marie Curie, Paris, France; MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France; Department of Cellular & Physiological Sciences, Life Sciences Institute, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; Departamento de Fisiología, Pontificia Universidad Católica de Chile, Santiago, Chile; Instituo de Neurociencias, Centro Interdisciplinario de Neurociencias, Universidad de Valparaíso, Valparaíso, Chile; Physiology Group, Department of Basic and Applied Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
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26
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Lagos-Cabré R, Burgos-Bravo F, Avalos AM, Leyton L. Connexins in Astrocyte Migration. Front Pharmacol 2020; 10:1546. [PMID: 32009957 PMCID: PMC6974553 DOI: 10.3389/fphar.2019.01546] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 11/29/2019] [Indexed: 12/18/2022] Open
Abstract
Astrocytes have long been considered the supportive cells of the central nervous system, but during the last decades, they have gained much more attention because of their active participation in the modulation of neuronal function. For example, after brain damage, astrocytes become reactive and undergo characteristic morphological and molecular changes, such as hypertrophy and increase in the expression of glial fibrillary acidic protein (GFAP), in a process known as astrogliosis. After severe damage, astrocytes migrate to the lesion site and proliferate, which leads to the formation of a glial scar. At this scar-forming stage, astrocytes secrete many factors, such as extracellular matrix proteins, cytokines, growth factors and chondroitin sulfate proteoglycans, stop migrating, and the process is irreversible. Although reactive gliosis is a normal physiological response that can protect brain cells from further damage, it also has detrimental effects on neuronal survival, by creating a hostile and non-permissive environment for axonal repair. The transformation of astrocytes from reactive to scar-forming astrocytes highlights migration as a relevant regulator of glial scar formation, and further emphasizes the importance of efficient communication between astrocytes in order to orchestrate cell migration. The coordination between astrocytes occurs mainly through Connexin (Cx) channels, in the form of direct cell-cell contact (gap junctions, GJs) or contact between the extracellular matrix and the astrocytes (hemichannels, HCs). Reactive astrocytes increase the expression levels of several proteins involved in astrocyte migration, such as αvβ3 Integrin, Syndecan-4 proteoglycan, the purinergic receptor P2X7, Pannexin1, and Cx43 HCs. Evidence has indicated that Cx43 HCs play a role in regulating astrocyte migration through the release of small molecules to the extracellular space, which then activate receptors in the same or adjacent cells to continue the signaling cascades required for astrocyte migration. In this review, we describe the communication of astrocytes through Cxs, the role of Cxs in inflammation and astrocyte migration, and discuss the molecular mechanisms that regulate Cx43 HCs, which may provide a therapeutic window of opportunity to control astrogliosis and the progression of neurodegenerative diseases.
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Affiliation(s)
- Raúl Lagos-Cabré
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies on Exercise, Metabolism and Cancer (CEMC), Facultad de Medicina, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Francesca Burgos-Bravo
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies on Exercise, Metabolism and Cancer (CEMC), Facultad de Medicina, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
| | - Ana María Avalos
- Facultad de Ciencias de la Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Lisette Leyton
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies on Exercise, Metabolism and Cancer (CEMC), Facultad de Medicina, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile, Santiago, Chile
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27
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Miterauer B, Baer W. Disorders of human consciousness in the Tri-partite synapses. Med Hypotheses 2020; 136:109523. [PMID: 31927223 DOI: 10.1016/j.mehy.2019.109523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 12/04/2019] [Accepted: 12/08/2019] [Indexed: 01/10/2023]
Abstract
Conscious Action Theory extends quantum theory to macroscopic phenomena and suggests physical correlates of consciousness occur at the intersection of external measurement signals and internally generated signals from memories that model the outside world. This physical theory predicts conscious phenomena happen at all scales and differ only by the size and complexity of material organizations involved. At the scale of the human "Brain" consciousness is predicted to happen where the processing loop of activity in the Glial network interfaces with the real world input-output processing loop of the Nuronal network. This happens at the Tripartite synapses creating an intersection plenum in biological systems that produces the experience of empty space and the objects it contains. Analysis of the transmitter-receptor strengths implementing the control and feedback between the Glial and Neuronal networks indicate imbalances can be directly related to schizophrenia, mania, epilepsy, and depression. This paper addresses three topics supporting the above mechanisms for normal consciousness functioning and its medical deviations. First we preset the architecture of a pan-psychic physical theory, which supports the hypothesis that tri-partite synapses are the location of human conscious experience. Second we discuss the inner workings of the Glial network to support long term memory and control functions corresponding to the inner feeling of the "I" self. Third, we consider the relation between psychiatric conditions and the balance states between the number of neuronal transmitters and astrocytic receptors.
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Affiliation(s)
- B Miterauer
- University of Salzburg, Volitronics-Institute, Wals, Austria
| | - W Baer
- Naval Postgraduate School, Monterey, CA, USA
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28
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Abstract
Astrocytes are critical for maintaining the homeostasis of the CNS. Increasing evidence suggests that a number of neurological and neuropsychiatric disorders, including chronic pain, may result from astrocyte 'gliopathy'. Indeed, in recent years there has been substantial progress in our understanding of how astrocytes can regulate nociceptive synaptic transmission via neuronal-glial and glial-glial cell interactions, as well as the involvement of spinal and supraspinal astrocytes in the modulation of pain signalling and the maintenance of neuropathic pain. A role of astrocytes in the pathogenesis of chronic itch is also emerging. These developments suggest that targeting the specific pathways that are responsible for astrogliopathy may represent a novel approach to develop therapies for chronic pain and chronic itch.
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29
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Hansson E, Skiöldebrand E. Low-grade inflammation causes gap junction-coupled cell dysfunction throughout the body, which can lead to the spread of systemic inflammation. Scand J Pain 2019; 19:639-649. [PMID: 31251727 DOI: 10.1515/sjpain-2019-0061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 05/21/2019] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND AIMS Gap junction-coupled cells form networks in different organs in the body. These networks can be affected by inflammatory stimuli and become dysregulated. Cell signaling is also changed through connexin-linked gap junctions. This alteration affects the surrounding cells and extracellular matrix in organs. These changes can cause the spread of inflammatory substances, thus affecting other network-linked cells in other organs in the body, which can give rise to systemic inflammation, which in turn can lead to pain that can turn into chronic. METHODS This is a review based on literature search and our own research data of inflammatory stimuli that can affect different organs and particularly gap-junction-coupled cells throughout the body. CONCLUSIONS A remaining question is which cell type or tissue is first affected by inflammatory stimuli. Can endotoxin exposure through the air, water and body start the process and are mast cells the first target cells that have the capacity to alter the physiological status of gap junction-coupled cells, thereby causing breakdown of different barrier systems? IMPLICATIONS Is it possible to address the right cellular and biochemical parameters and restore inflammatory systems to a normal physiological level by therapeutic strategies?
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Affiliation(s)
- Elisabeth Hansson
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Blå Stråket 7, 3rd Floor, SE 413 45 Gothenburg, Sweden, Phone: +46-31-786 3363
| | - Eva Skiöldebrand
- Section of Pathology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.,Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska University Hospital, Gothenburg University, Gothenburg, Sweden
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30
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Diverse Actions of Astrocytes in GABAergic Signaling. Int J Mol Sci 2019; 20:ijms20122964. [PMID: 31216630 PMCID: PMC6628243 DOI: 10.3390/ijms20122964] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 06/10/2019] [Accepted: 06/14/2019] [Indexed: 01/06/2023] Open
Abstract
An imbalance of excitatory and inhibitory neurotransmission leading to over excitation plays a crucial role in generating seizures, while enhancing GABAergic mechanisms are critical in terminating seizures. In recent years, it has been reported in many studies that astrocytes are deeply involved in synaptic transmission. Astrocytes form a critical component of the “tripartite” synapses by wrapping around the pre- and post-synaptic elements. From this location, astrocytes are known to greatly influence the dynamics of ions and transmitters in the synaptic cleft. Despite recent extensive research on excitatory tripartite synapses, inhibitory tripartite synapses have received less attention, even though they influence inhibitory synaptic transmission by affecting chloride and GABA concentration dynamics. In this review, we will discuss the diverse actions of astrocytic chloride and GABA homeostasis at GABAergic tripartite synapses. We will then consider the pathophysiological impacts of disturbed GABA homeostasis at the tripartite synapse.
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31
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Beiersdorfer A, Scheller A, Kirchhoff F, Lohr C. Panglial gap junctions between astrocytes and olfactory ensheathing cells mediate transmission of Ca 2+ transients and neurovascular coupling. Glia 2019; 67:1385-1400. [PMID: 30883940 DOI: 10.1002/glia.23613] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 02/22/2019] [Accepted: 02/25/2019] [Indexed: 12/13/2022]
Abstract
Astrocytes are arranged in highly organized gap junction-coupled networks, communicating via the propagation of Ca2+ waves. Astrocytes are gap junction-coupled not only to neighboring astrocytes, but also to oligodendrocytes, forming so-called panglial syncytia. It is not known, however, whether glial cells in panglial syncytia transmit information using Ca2+ signaling. We used confocal Ca2+ imaging to study intercellular communication between astrocytes and olfactory ensheathing glial cells (OECs) in in-toto preparations of the mouse olfactory bulb. Our results demonstrate that Ca2+ transients in juxtaglomerular astrocytes, evoked by local photolysis of "caged" ATP and "caged" tACPD, led to subsequent Ca2+ responses in OECs. This transmission of Ca2+ responses from astrocytes to OECs persisted in the presence of neuronal inhibition, but was absent when gap junctional coupling was suppressed with carbenoxolone. When Ca2+ transients were directly evoked in OECs by puff application of DHPG, they resulted in delayed Ca2+ responses in juxtaglomerular astrocytes, indicating that panglial transmission of Ca2+ signals occurred in a bidirectional manner. In addition, panglial transmission of Ca2+ signals from astrocytes to OECs resulted in vasoconstriction of OEC-associated blood vessels in the olfactory nerve layer. Our results demonstrate functional transmission of Ca2+ signals between different classes of glial cells within gap junction-coupled panglial networks and the resulting regulation of blood vessel diameter in the olfactory bulb.
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Affiliation(s)
| | - Anja Scheller
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Frank Kirchhoff
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Christian Lohr
- Division of Neurophysiology, University of Hamburg, Hamburg, Germany
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32
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Abstract
The gap junctions (GJs), which form intercellular communicating channels between two apposing cells or form hemichannel with extracellular environment, perform crucial functions to maintain small molecule homeostasis. The central nervous system (CNS) GJs are important for maintenance of myelin sheath and neuronal activity. Connexin (Cx) proteins are building blocks of GJs. Recent cell-biological investigations show that amongst the CNS specific Cxs, the most abundant Cx protein, Cx43 and its oligodendrocytic coupling partner Cx47 primarily important for maintenance of CNS myelin. Recent investigations elucidate that the expression of Cx43 and Cx47 is very important to maintain K+ buffering and nutrient homeostasis in oligodendrocytes, CNS myelin and oligodendrocyte function. The investigations on Multiple Sclerosis (MS) patient samples and EAE hypothesized that the functional loss of Cx43/Cx47 could be associated with spread of chronic MS lesions. Exploring the mechanism of initial GJ alteration and its effect on demyelination in this model of MS might play a primary role to understand the basis of altered CNS homeostasis, observed during MS. In this review, we mainly discuss the role of CNS GJs, specifically the Cx43/Cx47 axis in the perspective of demyelination.
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33
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Lallouette J, De Pittà M, Berry H. Astrocyte Networks and Intercellular Calcium Propagation. SPRINGER SERIES IN COMPUTATIONAL NEUROSCIENCE 2019. [DOI: 10.1007/978-3-030-00817-8_7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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34
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Ichkova A, Fukuda AM, Nishiyama N, Paris G, Obenaus A, Badaut J. Small Interference RNA Targeting Connexin-43 Improves Motor Function and Limits Astrogliosis After Juvenile Traumatic Brain Injury. ASN Neuro 2019; 11:1759091419847090. [PMID: 31194577 PMCID: PMC6566476 DOI: 10.1177/1759091419847090] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/28/2019] [Accepted: 03/29/2019] [Indexed: 01/22/2023] Open
Abstract
Juvenile traumatic brain injury (jTBI) is the leading cause of death and disability for children and adolescents worldwide, but there are no pharmacological treatments available. Aquaporin 4 (AQP4), an astrocytic perivascular protein, is increased after jTBI, and inhibition of its expression with small interference RNA mitigates edema formation and reduces the number of reactive astrocytes after jTBI. Due to the physical proximity of AQP4 and gap junctions, coregulation of AQP4 and connexin 43 (Cx43) expressions, and the possibility of water diffusion via gap junctions, we decided to address the potential role of astrocytic gap junctions in jTBI pathophysiology. We evaluated the role of Cx43 in the spread of the secondary injuries via the astrocyte network, such as edema formation associated with blood–brain barrier dysfunctions, astrogliosis, and behavioral outcome. We observed that Cx43 was altered after jTBI with increased expression in the perilesional cortex and in the hippocampus at several days post injury. In a second set of experiments, cortical injection of small interference RNA against Cx43 decreased Cx43 protein expression, improved motor function recovery, and decreased astrogliosis but did not result in differences in edema formation as measured via T2-weighted imaging or diffusion-weighted imaging at 1 day or 3 days. Based on our findings, we can speculate that while decreasing Cx43 has beneficial roles, it likely does not contribute to the spread of edema early after jTBI.
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Affiliation(s)
| | - Andrew M. Fukuda
- Department of Physiology, Loma Linda University, CA, USA
- Department of Pediatrics, Loma Linda University Medical Center, CA, USA
- Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA
| | - Nina Nishiyama
- Department of Pediatrics, Loma Linda University Medical Center, CA, USA
| | - Germaine Paris
- Department of Pediatrics, Loma Linda University Medical Center, CA, USA
| | - Andre Obenaus
- Department of Pediatrics, Loma Linda University Medical Center, CA, USA
- Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, University of California, Riverside, CA, USA
- Department of Pediatrics, University of California, Irvine, CA, USA
| | - Jerome Badaut
- CNRS UMR5287, University of Bordeaux, France
- Department of Physiology, Loma Linda University, CA, USA
- Department of Pediatrics, Loma Linda University Medical Center, CA, USA
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Basu R, Sarma JDAS. Connexin 43/47 channels are important for astrocyte/ oligodendrocyte cross-talk in myelination and demyelination. J Biosci 2018; 43:1055-1068. [PMID: 30541963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2022]
Abstract
The gap junctions (GJs), which form intercellular communicating channels between two apposing cells or form hemichannel with extracellular environment, perform crucial functions to maintain small molecule homeostasis. The central nervous system (CNS) GJs are important for maintenance of myelin sheath and neuronal activity. Connexin (Cx) proteins are building blocks of GJs. Recent cell-biological investigations show that amongst the CNS specific Cxs, the most abundant Cx protein, Cx43 and its oligodendrocytic coupling partner Cx47 primarily important for maintenance of CNS myelin. Recent investigations elucidate that the expression of Cx43 and Cx47 is very important to maintain K? buffering and nutrient homeostasis in oligodendrocytes, CNS myelin and oligodendrocyte function. The investigations on Multiple Sclerosis (MS) patient samples and EAE hypothesized that the functional loss of Cx43/Cx47 could be associated with spread of chronic MS lesions. Exploring the mechanism of initial GJ alteration and its effect on demyelination in this model of MS might play a primary role to understand the basis of altered CNS homeostasis, observed during MS. In this review, we mainly discuss the role of CNS GJs, specifically the Cx43/Cx47 axis in the perspective of demyelination.
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Affiliation(s)
- Rahul Basu
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
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Dave S, Chen L, Yu C, Seaton M, Khodr CE, Al-Harthi L, Hu XT. Methamphetamine decreases K + channel function in human fetal astrocytes by activating the trace amine-associated receptor type-1. J Neurochem 2018; 148:29-45. [PMID: 30295919 DOI: 10.1111/jnc.14606] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 09/28/2018] [Accepted: 10/03/2018] [Indexed: 12/22/2022]
Abstract
Methamphetamine (Meth) is a potent and commonly abused psychostimulant. Meth alters neuron and astrocyte activity; yet the underlying mechanism(s) is not fully understood. Here we assessed the impact of acute Meth on human fetal astrocytes (HFAs) using whole-cell patch-clamping. We found that HFAs displayed a large voltage-gated K+ efflux (IKv ) through Kv /Kv -like channels during membrane depolarization, and a smaller K+ influx (Ikir ) via inward-rectifying Kir /Kir -like channels during membrane hyperpolarization. Meth at a 'recreational' (20 μM) or toxic/fatal (100 μM) concentration depolarized resting membrane potential (RMP) and suppressed IKv/Kv-like . These changes were associated with a decreased time constant (Ƭ), and mimicked by blocking the two-pore domain K+ (K2P )/K2P -like and Kv /Kv -like channels, respectively. Meth also diminished IKir/Kir-like , but only at toxic/fatal levels. Given that Meth is a potent agonist for the trace amine-associated receptor type-1 (TAAR1), and TAAR1-coupled cAMP/cAMP-activated protein kinase (PKA) cascade, we further evaluated whether the Meth impact on K+ efflux was mediated by this pathway. We found that antagonizing TAAR1 with N-(3-Ethoxyphenyl)-4-(1-pyrrolidinyl)-3-(trifluoromethyl)benzamide (EPPTB) reversed Meth-induced suppression of IKv/Kv-like ; and inhibiting PKA activity by H89 abolished Meth effects on suppressing IKv/Kv-like . Antagonizing TAAR1 might also attenuate Meth-induced RMP depolarization. Voltage-gated Ca2+ currents were not detected in HFAs. These novel findings demonstrate that Meth suppresses IKv/Kv-like by facilitating the TAAR1/Gs /cAMP/PKA cascade and altering the kinetics of Kv /Kv -like channel gating, but reduces K2P /K2P -like channel activity through other pathway(s), in HFAs. Given that Meth-induced decrease in astrocytic K+ efflux through K2P /K2P -like and Kv /Kv -like channels reduces extracellular K+ levels, such reduction could consequently contribute to a decreased excitability of surrounding neurons. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Sonya Dave
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, Illinois, USA
| | - Lihua Chen
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, Illinois, USA
| | - Chunjiang Yu
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, Illinois, USA
| | - Melanie Seaton
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, Illinois, USA
| | - Christina E Khodr
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, Illinois, USA
| | - Lena Al-Harthi
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, Illinois, USA
| | - Xiu-Ti Hu
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, Illinois, USA
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Robertson JM. The Gliocentric Brain. Int J Mol Sci 2018; 19:ijms19103033. [PMID: 30301132 PMCID: PMC6212929 DOI: 10.3390/ijms19103033] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 09/23/2018] [Accepted: 09/28/2018] [Indexed: 01/10/2023] Open
Abstract
The Neuron Doctrine, the cornerstone of research on normal and abnormal brain functions for over a century, has failed to discern the basis of complex cognitive functions. The location and mechanisms of memory storage and recall, consciousness, and learning, remain enigmatic. The purpose of this article is to critically review the Neuron Doctrine in light of empirical data over the past three decades. Similarly, the central role of the synapse and associated neural networks, as well as ancillary hypotheses, such as gamma synchrony and cortical minicolumns, are critically examined. It is concluded that each is fundamentally flawed and that, over the past three decades, the study of non-neuronal cells, particularly astrocytes, has shown that virtually all functions ascribed to neurons are largely the result of direct or indirect actions of glia continuously interacting with neurons and neural networks. Recognition of non-neural cells in higher brain functions is extremely important. The strict adherence of purely neurocentric ideas, deeply ingrained in the great majority of neuroscientists, remains a detriment to understanding normal and abnormal brain functions. By broadening brain information processing beyond neurons, progress in understanding higher level brain functions, as well as neurodegenerative and neurodevelopmental disorders, will progress beyond the impasse that has been evident for decades.
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Kumar J, Solaiman A, Mahakkanukrauh P, Mohamed R, Das S. Sleep Related Epilepsy and Pharmacotherapy: An Insight. Front Pharmacol 2018; 9:1088. [PMID: 30319421 PMCID: PMC6171479 DOI: 10.3389/fphar.2018.01088] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 09/07/2018] [Indexed: 01/26/2023] Open
Abstract
In the last several decades, sleep-related epilepsy has drawn considerable attention among epileptologists and neuroscientists in the interest of new paradigms of the disease etiology, pathogenesis and management. Sleep-related epilepsy is nocturnal seizures that manifest solely during the sleep state. Sleep comprises two distinct stages i.e., non-rapid eye movement (NREM) and rapid eye movement (REM) that alternate every 90 min with NREM preceding REM. Current findings indicate that the sleep-related epilepsy manifests predominantly during the synchronized stages of sleep; NREM over REM stage. Sleep related hypermotor epilepsy (SHE), benign partial epilepsy with centrotemporal spikes or benign rolandic epilepsy (BECTS), and Panayiotopoulos Syndrome (PS) are three of the most frequently implicated epilepsies occurring during the sleep state. Although some familial types are described, others are seemingly sporadic occurrences. In the present review, we aim to discuss the predominance of sleep-related epilepsy during NREM, established familial links to the pathogenesis of SHE, BECTS and PS, and highlight the present available pharmacotherapy options.
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Affiliation(s)
- Jaya Kumar
- Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Amro Solaiman
- Department of Anatomy, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Pasuk Mahakkanukrauh
- Department of Anatomy, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Excellence Centre in Forensic Osteology Research Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Rashidi Mohamed
- Department of Familty Medicine, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Srijit Das
- Department of Anatomy, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
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Dong A, Liu S, Li Y. Gap Junctions in the Nervous System: Probing Functional Connections Using New Imaging Approaches. Front Cell Neurosci 2018; 12:320. [PMID: 30283305 PMCID: PMC6156252 DOI: 10.3389/fncel.2018.00320] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 09/03/2018] [Indexed: 11/13/2022] Open
Abstract
Gap junctions are channels that physically connect adjacent cells, mediating the rapid exchange of small molecules, and playing an essential role in a wide range of physiological processes in nearly every system in the body, including the nervous system. Thus, altered function of gap junctions has been linked with a plethora of diseases and pathological conditions. Being able to measure and characterize the distribution, function, and regulation of gap junctions in intact tissue is therefore essential for understanding the physiological and pathophysiological roles that gap junctions play. In recent decades, several robust in vitro and in vivo methods have been developed for detecting and characterizing gap junctions. Here, we review the currently available methods with respect to invasiveness, signal-to-noise ratio, temporal resolution and others, highlighting the recently developed chemical tracers and hybrid imaging systems that use novel chemical compounds and/or genetically encoded enzymes, transporters, channels, and fluorescent proteins in order to map gap junctions. Finally, we discuss possible avenues for further improving existing techniques in order to achieve highly sensitive, cell type-specific, non-invasive measures of in vivo gap junction function with high throughput and high spatiotemporal resolution.
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Affiliation(s)
- Ao Dong
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Simin Liu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
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40
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Biochemical alterations in inflammatory reactive chondrocytes: evidence for intercellular network communication. Heliyon 2018; 4:e00525. [PMID: 29560438 PMCID: PMC5857518 DOI: 10.1016/j.heliyon.2018.e00525] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/04/2018] [Accepted: 01/23/2018] [Indexed: 12/24/2022] Open
Abstract
Chondrocytes are effectively involved in the pathophysiological processes of inflammation in joints. They form cellular processes in the superficial layer of the articular cartilage and form gap junction coupled syncytium to facilitate cell-to-cell communication. However, very little is known about their physiological cellular identity and communication. The aim with the present work is to evaluate the physiological behavior after stimulation with the inflammatory inducers interleukin-1β and lipopolysaccharide. The cytoskeleton integrity and intracellular Ca2+ release were assessed as indicators of inflammatory state. Cytoskeleton integrity was analyzed through cartilage oligomeric matrix protein and actin labeling with an Alexa 488-conjugated phalloidin probe. Ca2+ responses were assessed through the Ca2+ sensitive fluorophore Fura-2/AM. Western blot analyses of several inflammatory markers were performed. The results show reorganization of the actin filaments. Glutamate, 5-hydoxytryptamine, and ATP evoked intracellular Ca2+ release changed from single peaks to oscillations after inflammatory induction in the chondrocytes. The expression of toll-like receptor 4, the glutamate transporters GLAST and GLT-1, and the matrix metalloproteinase-13 increased. This work demonstrates that chondrocytes are a key part in conditions that lead to inflammation in the cartilage. The inflammatory inducers modulate the cytoskeleton, the Ca2+ signaling, and several inflammatory parameters. In conclusion, our data show that the cellular responses to inflammatory insults from healthy and inflammatory chondrocytes resemble those previously observed in astrocyte and cardiac fibroblasts networks.
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41
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Chen W, Guo Y, Yang W, Chen L, Ren D, Wu C, He B, Zheng P, Tong W. Phosphorylation of connexin 43 induced by traumatic brain injury promotes exosome release. J Neurophysiol 2017; 119:305-311. [PMID: 29046426 DOI: 10.1152/jn.00654.2017] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Traumatic brain injury (TBI) caused by the external force leads to the neuronal dysfunction and even death. TBI has been reported to significantly increase the phosphorylation of glial gap junction protein connexin 43 (Cx43), which in turn propagates damages into surrounding brain tissues. However, the neuroprotective and anti-apoptosis effects of glia-derived exosomes have also been implicated in recent studies. Therefore, we detected whether TBI-induced phosphorylation of Cx43 would promote exosome release in rat brain. To generate TBI model, adult male Sprague-Dawley rats were subjected to lateral fluid percussion injury. Phosphorylated Cx43 protein levels and exosome activities were quantified using Western blot analysis following TBI. Long-term potentiation (LTP) was also tested in rat hippocampal slices. TBI significantly increased the phosphorylated Cx43 and exosome markers expression in rat ipsilateral hippocampus, but not cortex. Blocking the activity of Cx43 or ERK, but not JNK, significantly suppressed TBI-induced exosome release in hippocampus. Furthermore, TBI significantly inhibited the induction of LTP in hippocampal slices, which could be partially but significantly restored by pretreatment with exosomes. The results imply that TBI-activated Cx43 could mediate a nociceptive effect by propagating the brain damages, as well as a neuroprotective effect by promoting exosome release. NEW & NOTEWORTHY We have demonstrated in rat traumatic brain injury (TBI) models that both phosphorylated connexin 43 (p-Cx43) expression and exosome release were elevated in the hippocampus following TBI. The promoted exosome release depends on the phosphorylation of Cx43 and requires ERK signaling activation. Exosome treatment could partially restore the attenuated long-term potentiation. Our results provide new insight for future therapeutic direction on the functional recovery of TBI by promoting p-Cx43-dependent exosome release but limiting the gap junction-mediated bystander effect.
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Affiliation(s)
- Wei Chen
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
| | - Yijun Guo
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
| | - Wenjin Yang
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
| | - Lei Chen
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
| | - Dabin Ren
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
| | - Chenxing Wu
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
| | - Bin He
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
| | - Ping Zheng
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
| | - Wusong Tong
- The People's Hospital of Pu Dong New Area, Chuansha New Town, Shanghai , People's Republic of China
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42
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Liu B, Teschemacher AG, Kasparov S. Astroglia as a cellular target for neuroprotection and treatment of neuro-psychiatric disorders. Glia 2017; 65:1205-1226. [PMID: 28300322 PMCID: PMC5669250 DOI: 10.1002/glia.23136] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 02/15/2017] [Accepted: 02/17/2017] [Indexed: 12/12/2022]
Abstract
Astrocytes are key homeostatic cells of the central nervous system. They cooperate with neurons at several levels, including ion and water homeostasis, chemical signal transmission, blood flow regulation, immune and oxidative stress defense, supply of metabolites and neurogenesis. Astroglia is also important for viability and maturation of stem-cell derived neurons. Neurons critically depend on intrinsic protective and supportive properties of astrocytes. Conversely, all forms of pathogenic stimuli which disturb astrocytic functions compromise neuronal functionality and viability. Support of neuroprotective functions of astrocytes is thus an important strategy for enhancing neuronal survival and improving outcomes in disease states. In this review, we first briefly examine how astrocytic dysfunction contributes to major neurological disorders, which are traditionally associated with malfunctioning of processes residing in neurons. Possible molecular entities within astrocytes that could underpin the cause, initiation and/or progression of various disorders are outlined. In the second section, we explore opportunities enhancing neuroprotective function of astroglia. We consider targeting astrocyte-specific molecular pathways which are involved in neuroprotection or could be expected to have a therapeutic value. Examples of those are oxidative stress defense mechanisms, glutamate uptake, purinergic signaling, water and ion homeostasis, connexin gap junctions, neurotrophic factors and the Nrf2-ARE pathway. We propose that enhancing the neuroprotective capacity of astrocytes is a viable strategy for improving brain resilience and developing new therapeutic approaches.
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Affiliation(s)
- Beihui Liu
- School of Physiology, Pharmacology and NeuroscienceUniversity of Bristol, University WalkBS8 1TDUnited Kingdom
| | - Anja G. Teschemacher
- School of Physiology, Pharmacology and NeuroscienceUniversity of Bristol, University WalkBS8 1TDUnited Kingdom
| | - Sergey Kasparov
- School of Physiology, Pharmacology and NeuroscienceUniversity of Bristol, University WalkBS8 1TDUnited Kingdom
- Institute for Chemistry and BiologyBaltic Federal UniversityKaliningradRussian Federation
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43
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Gao Q, Katakowski M, Chen X, Li Y, Chopp M. Human Marrow Stromal Cells Enhance Connexin43 Gap Junction Intercellular Communication in Cultured Astrocytes. Cell Transplant 2017; 14:109-17. [PMID: 15881420 DOI: 10.3727/000000005783983205] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Human marrow stromal cells (hMSCs) provide functional benefit in rats subjected to stroke. Astrocytes are coupled into a cellular network via gap junction channels, predominantly composed of connexin-43 (Cx43) proteins. Astrocytes are believed to play a vital role in neuroprotection by providing energy substrates to neurons and by regulating the concentrations of K+ and neurotransmitters via gap junctions. We therefore investigated the effect of factors secreted by hMSCs on gap junction intercellular communication (GJIC), expression of Cx43, and phosphorylation of Cx43 in an astrocyte cell culture system. Exposing rat cortical astrocytes to various concentrations of hMSC conditioned medium, we demonstrate that hMSCs produce soluble factors that significantly increase astrocytic GJIC, measured by the scrape-loading dye transfer method. Immunohistochemistry and Western blot showed increased Cx43 expression concomitant with altered GJIC. As the PI3K/Akt signaling pathway has been demonstrated to alter gap junction expression and GJIC, we selectively blocked phosphoinositide 3-kinase (PI3K). Addition of the PI3K inhibitor LY294002 decreased GJIC and Cx43 expression in astrocytes. These inhibitory effects of LY294002 were countered by the addition of hMSC conditioned media. Furthermore, coculturing hMSCs with rat astrocytes increased astrocyte GJIC in a manner dependent upon the hMSC/astrocyte ratio. These findings demonstrate that hMSCs secrete soluble factors that increase GJIC of astrocytes through upregulation of Cx43, and indicate a mechanistic role for PI3K.
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Affiliation(s)
- Qi Gao
- Department of Neurology, Henry Ford Health Sciences Center, Detroit, MI 48202, USA
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44
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Charvériat M, Naus CC, Leybaert L, Sáez JC, Giaume C. Connexin-Dependent Neuroglial Networking as a New Therapeutic Target. Front Cell Neurosci 2017; 11:174. [PMID: 28694772 PMCID: PMC5483454 DOI: 10.3389/fncel.2017.00174] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 06/08/2017] [Indexed: 12/12/2022] Open
Abstract
Astrocytes and neurons dynamically interact during physiological processes, and it is now widely accepted that they are both organized in plastic and tightly regulated networks. Astrocytes are connected through connexin-based gap junction channels, with brain region specificities, and those networks modulate neuronal activities, such as those involved in sleep-wake cycle, cognitive, or sensory functions. Additionally, astrocyte domains have been involved in neurogenesis and neuronal differentiation during development; they participate in the “tripartite synapse” with both pre-synaptic and post-synaptic neurons by tuning down or up neuronal activities through the control of neuronal synaptic strength. Connexin-based hemichannels are also involved in those regulations of neuronal activities, however, this feature will not be considered in the present review. Furthermore, neuronal processes, transmitting electrical signals to chemical synapses, stringently control astroglial connexin expression, and channel functions. Long-range energy trafficking toward neurons through connexin-coupled astrocytes and plasticity of those networks are hence largely dependent on neuronal activity. Such reciprocal interactions between neurons and astrocyte networks involve neurotransmitters, cytokines, endogenous lipids, and peptides released by neurons but also other brain cell types, including microglial and endothelial cells. Over the past 10 years, knowledge about neuroglial interactions has widened and now includes effects of CNS-targeting drugs such as antidepressants, antipsychotics, psychostimulants, or sedatives drugs as potential modulators of connexin function and thus astrocyte networking activity. In physiological situations, neuroglial networking is consequently resulting from a two-way interaction between astrocyte gap junction-mediated networks and those made by neurons. As both cell types are modulated by CNS drugs we postulate that neuroglial networking may emerge as new therapeutic targets in neurological and psychiatric disorders.
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Affiliation(s)
| | - Christian C Naus
- Department of Cellular and Physiological Science, Life Science Institute, University of British ColumbiaVancouver, BC, Canada
| | - Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent UniversityGhent, Belgium
| | - Juan C Sáez
- Departamento de Fisiología, Pontificia Universidad Católica de ChileSantiago, Chile.,Centro Interdisciplinario de Neurociencias de Valparaíso, Instituto MilenioValparaíso, Chile
| | - Christian Giaume
- Center of Interdisciplinary Research in Biology, Collège de FranceParis, France
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Abstract
In a career that has spanned 45 years and shows no signs of slowing down, Dr Bruce Ransom has devoted considerable time and energy to studying regulation of interstitial K+. When Bruce commenced his studies in 1969 virtually nothing was known of the functions of glial cells, but Bruce’s research contributed to the physiological assignation of function to mammalian astrocytes, namely interstitial K+ buffering. The experiments that I describe in this review concern the response of the membrane potential (Em) of in vivo cat cortical astrocytes to changes in [K+]o, an experimental manoeuvre that was achieved in two different ways. The first involved recording the Em of an astrocyte while the initial aCSF was switched to one with different K+, whereas in the second series of experiments the cortex was stimulated and the response of the astrocyte Em to the K+ released from neighbouring neurons was recorded. The astrocytes responded in a qualitatively predictable manner, but quantitatively the changes were not as predicted by the Nernst equation. Elevations in interstitial K+ are not sustained and K+ returns to baseline rapidly due to the buffering capacity of astrocytes, a phenomenon studied by Bruce, and his son Chris, published 27 years after Bruce’s initial publications. Thus, a lifetime spent investigating K+ buffering has seen enormous advances in glial research, from the time cells were identified as ‘presumed’ glial cells or ‘silent cells’, to the present day, where glial cells are recognised as contributing to every important physiological brain function.
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Affiliation(s)
- Angus M Brown
- School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK. .,Department of Neurology, University of Washington, Seattle, WA, 98195, USA.
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46
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Basu R, Bose A, Thomas D, Das Sarma J. Microtubule-assisted altered trafficking of astrocytic gap junction protein connexin 43 is associated with depletion of connexin 47 during mouse hepatitis virus infection. J Biol Chem 2017; 292:14747-14763. [PMID: 28566289 DOI: 10.1074/jbc.m117.786491] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 05/16/2017] [Indexed: 11/06/2022] Open
Abstract
Gap junctions (GJs) are important for maintenance of CNS homeostasis. GJ proteins, connexin 43 (Cx43) and connexin 47 (Cx47), play a crucial role in production and maintenance of CNS myelin. Cx43 is mainly expressed by astrocytes in the CNS and forms gap junction intercellular communications between astrocytes-astrocytes (Cx43-Cx43) and between astrocytes-oligodendrocytes (Cx43-Cx47). Mutations of these connexin (Cx) proteins cause dysmyelinating diseases in humans. Previously, it has been shown that Cx43 localization and expression is altered due to mouse hepatitis virus (MHV)-A59 infection both in vivo and in vitro; however, its mechanism and association with loss of myelin protein was not elaborated. Thus, we explored potential mechanisms by which MHV-A59 infection alters Cx43 localization and examined the effects of viral infection on Cx47 expression and its association with loss of the myelin marker proteolipid protein. Immunofluorescence and total internal reflection fluorescence microscopy confirmed that MHV-A59 used microtubules (MTs) as a conduit to reach the cell surface and restricted MT-mediated Cx43 delivery to the cell membrane. Co-immunoprecipitation experiments demonstrated that Cx43-β-tubulin molecular interaction was depleted due to protein-protein interaction between viral particles and MTs. During acute MHV-A59 infection, oligodendrocytic Cx47, which is mainly stabilized by Cx43 in vivo, was down-regulated, and its characteristic staining remained disrupted even at chronic phase. The loss of Cx47 was associated with loss of proteolipid protein at the chronic stage of MHV-A59 infection.
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Affiliation(s)
- Rahul Basu
- From the Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, India
| | - Abhishek Bose
- From the Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, India
| | - Deepthi Thomas
- From the Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, India
| | - Jayasri Das Sarma
- From the Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, India
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47
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Wang Q, Jie W, Liu JH, Yang JM, Gao TM. An astroglial basis of major depressive disorder? An overview. Glia 2017; 65:1227-1250. [DOI: 10.1002/glia.23143] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 02/26/2017] [Accepted: 02/27/2017] [Indexed: 12/11/2022]
Affiliation(s)
- Qian Wang
- State Key Laboratory of Organ Failure Research, Key Laboratory of Psychiatric Disorders of Guangdong Province, Collaborative Innovation Center for Brain Science, Department of Neurobiology, Southern Medical University; Guangzhou 510515 China
| | - Wei Jie
- State Key Laboratory of Organ Failure Research, Key Laboratory of Psychiatric Disorders of Guangdong Province, Collaborative Innovation Center for Brain Science, Department of Neurobiology, Southern Medical University; Guangzhou 510515 China
| | - Ji-Hong Liu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Psychiatric Disorders of Guangdong Province, Collaborative Innovation Center for Brain Science, Department of Neurobiology, Southern Medical University; Guangzhou 510515 China
| | - Jian-Ming Yang
- State Key Laboratory of Organ Failure Research, Key Laboratory of Psychiatric Disorders of Guangdong Province, Collaborative Innovation Center for Brain Science, Department of Neurobiology, Southern Medical University; Guangzhou 510515 China
| | - Tian-Ming Gao
- State Key Laboratory of Organ Failure Research, Key Laboratory of Psychiatric Disorders of Guangdong Province, Collaborative Innovation Center for Brain Science, Department of Neurobiology, Southern Medical University; Guangzhou 510515 China
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48
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Hossain MZ, Shinoda M, Unno S, Ando H, Masuda Y, Iwata K, Kitagawa J. Involvement of microglia and astroglia in modulation of the orofacial motor functions in rats with neuropathic pain. J Oral Biosci 2017. [DOI: 10.1016/j.job.2016.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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49
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Harris JJ, Reynell C. How do antidepressants influence the BOLD signal in the developing brain? Dev Cogn Neurosci 2016; 25:45-57. [PMID: 28089656 PMCID: PMC6987820 DOI: 10.1016/j.dcn.2016.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 12/12/2016] [Accepted: 12/12/2016] [Indexed: 11/21/2022] Open
Abstract
Depression is a highly prevalent life-threatening disorder, with its first onset commonly occurring during adolescence. Adolescent depression is increasingly being treated with antidepressants, such as fluoxetine. The use of medication during this sensitive period of physiological and cognitive brain development produces neurobiological changes, some of which may outlast the course of treatment. In this review, we look at how antidepressant treatment in adolescence is likely to alter neurovascular coupling and brain energy use and how these changes, in turn, affect our ability to identify neuronal activity changes between participant groups. BOLD (blood oxygen level dependent) fMRI (functional magnetic resonance imaging), the method most commonly used to record brain activity in humans, is an indirect measure of neuronal activity. This means that between-group comparisons – adolescent versus adult, depressed versus healthy, medicated versus non-medicated – rely upon a stable relationship existing between neuronal activity and the BOLD response across these groups. We use data from animal studies to detail the ways in which fluoxetine may alter this relationship, and explore how these alterations may influence the interpretation of BOLD signal differences between groups that have been treated with fluoxetine and those that have not.
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Affiliation(s)
- Julia J Harris
- Life Sciences Department, Imperial College London, SW7 2AZ, UK; Francis Crick Institute, Midland Road, London, NW1 1AT, UK.
| | - Clare Reynell
- Département de Neurosciences, Université de Montréal, H3C 3J7, Canada.
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50
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Quinolinic acid neurotoxicity: Differential roles of astrocytes and microglia via FGF-2-mediated signaling in redox-linked cytoskeletal changes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:3001-3014. [PMID: 27663072 DOI: 10.1016/j.bbamcr.2016.09.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/12/2016] [Accepted: 09/17/2016] [Indexed: 11/24/2022]
Abstract
QUIN is a glutamate agonist playing a role in the misregulation of the cytoskeleton, which is associated with neurodegeneration in rats. In this study, we focused on microglial activation, FGF2/Erk signaling, gap junctions (GJs), inflammatory parameters and redox imbalance acting on cytoskeletal dynamics of the in QUIN-treated neural cells of rat striatum. FGF-2/Erk signaling was not altered in QUIN-treated primary astrocytes or neurons, however cytoskeleton was disrupted. In co-cultured astrocytes and neurons, QUIN-activated FGF2/Erk signaling prevented the cytoskeleton from remodeling. In mixed cultures (astrocyte, neuron, microglia), QUIN-induced FGF-2 increased level failed to activate Erk and promoted cytoskeletal destabilization. The effects of QUIN in mixed cultures involved redox imbalance upstream of Erk activation. Decreased connexin 43 (Cx43) immunocontent and functional GJs, was also coincident with disruption of the cytoskeleton in primary astrocytes and mixed cultures. We postulate that in interacting astrocytes and neurons the cytoskeleton is preserved against the insult of QUIN by activation of FGF-2/Erk signaling and proper cell-cell interaction through GJs. In mixed cultures, the FGF-2/Erk signaling is blocked by the redox imbalance associated with microglial activation and disturbed cell communication, disrupting the cytoskeleton. Thus, QUIN signal activates differential mechanisms that could stabilize or destabilize the cytoskeleton of striatal astrocytes and neurons in culture, and glial cells play a pivotal role in these responses preserving or disrupting a combination of signaling pathways and cell-cell interactions. Taken together, our findings shed light into the complex role of the active interaction of astrocytes, neurons and microglia in the neurotoxicity of QUIN.
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