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Passarelli JP, Nimjee SM, Townsend KL. Stroke and Neurogenesis: Bridging Clinical Observations to New Mechanistic Insights from Animal Models. Transl Stroke Res 2024; 15:53-68. [PMID: 36462099 DOI: 10.1007/s12975-022-01109-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 12/04/2022]
Abstract
Stroke was the 2nd leading cause of death and a major cause of morbidity. Unfortunately, there are limited means to promote neurological recovery post-stroke, but research has unearthed potential targets for therapies to encourage post-stroke neurogenesis and neuroplasticity. The occurrence of neurogenesis in adult mammalian brains, including humans, was not widely accepted until the 1990s. Now, adult neurogenesis has been extensively studied in human and mouse neurogenic brain niches, of which the subventricular zone of the lateral ventricles and subgranular zone of the dentate gyrus are best studied. Numerous other niches are under investigation for neurogenic potential. This review offers a basic overview to stroke in the clinical setting, a focused summary of recent and foundational research literature on cortical neurogenesis and post-stroke brain plasticity, and insights regarding how the meninges and choroid plexus have emerged as key players in neurogenesis and neuroplasticity in the context of focal cerebral ischemia disrupting the anterior circulation. The choroid plexus and meninges are vital as they are integral sites for neuroimmune interactions, glymphatic perfusion, and niche signaling pertinent to neural stem cells and neurogenesis. Modulating neuroimmune interactions with a focus on astrocyte activity, potentially through manipulation of the choroid plexus and meningeal niches, may reduce the exacerbation of stroke by inflammatory mediators and create an environment conducive to neurorecovery. Furthermore, addressing impaired glymphatic perfusion after ischemic stroke likely supports a neurogenic environment by clearing out inflammatory mediators, neurotoxic metabolites, and other accumulated waste. The meninges and choroid plexus also contribute more directly to promoting neurogenesis: the meninges are thought to harbor neural stem cells and are a niche amenable to neural stem/progenitor cell migration. Additionally, the choroid plexus has secretory functions that directly influences stem cells through signaling mechanisms and growth factor actions. More research to better understand the functions of the meninges and choroid plexus may lead to novel approaches for stimulating neuronal recovery after ischemic stroke.
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Affiliation(s)
| | - Shahid M Nimjee
- Department of Neurological Surgery, The Ohio State University Wexner Medical Center, Biomedical Research Tower, 460 W 12th Avenue, Columbus, OH, 43210, USA
| | - Kristy L Townsend
- Department of Neurological Surgery, The Ohio State University Wexner Medical Center, Biomedical Research Tower, 460 W 12th Avenue, Columbus, OH, 43210, USA.
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Zhai Q, Zhang Y, Ye M, Zhu S, Sun J, Wang Y, Deng B, Ma D, Wang Q. Reducing complement activation during sleep deprivation yields cognitive improvement by dexmedetomidine. Br J Anaesth 2023; 131:542-555. [PMID: 37517957 DOI: 10.1016/j.bja.2023.04.044] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 04/24/2023] [Accepted: 04/25/2023] [Indexed: 08/01/2023] Open
Abstract
BACKGROUND Sleep loss and its associated conditions (e.g. cognitive deficits) represent a large societal burden, but the underlying mechanisms of these cognitive deficits remain unknown. This study assessed the effect of dexmedetomidine (DEX) on cognitive decline induced by sleep loss. METHODS C57BL/6 mice were subjected to chronic sleep restriction (CSR) for 20 h (5 pm-1 pm the next day) daily for 7 days, and cognitive tests were subsequently carried out. The neuromolecular and cellular changes that occurred in the presence and absence of DEX (100 μg kg-1, i.v., at 1 pm and 3 pm every day) were also investigated. RESULTS CSR mice displayed a decline in learning and memory by 12% (P<0.05) in the Y-maze and by 18% (P<0.01) in the novel object recognition test; these changes were associated with increases in microglial activation, CD68+ microglial phagosome counts, astrocyte-derived complement C3 secretion, and microglial C3a receptor expression (all P<0.05). Synapse elimination, as indicated by a 66% decrease in synaptophysin expression (P=0.0004) and a 45% decrease in postsynaptic density protein-95 expression (P=0.0003), was associated with the occurrence of cognitive deficits. DEX activated astrocytic α2A adrenoceptors and inhibited astrocytic complement C3 release to attenuate synapse elimination through microglial phagocytosis. DEX restored synaptic connections and reversed cognitive deficits induced by CSR. CONCLUSIONS The results demonstrate that complement pathway activation associated with synapse elimination contributes to sleep loss-related cognitive deficits and that dexmedetomidine protects against sleep deprivation-induced complement activation. Dexmedetomidine holds potential for preventing cognitive deficits associated with sleep loss, which warrants further study.
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Affiliation(s)
- Qian Zhai
- Department of Anaesthesiology and Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Ying Zhang
- Department of Anaesthesiology and Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Mao Ye
- Department of Anaesthesiology and Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Shan Zhu
- Department of Anaesthesiology and Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Jianyu Sun
- Department of Anaesthesiology and Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Yue Wang
- Department of Anaesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Bin Deng
- Department of Anaesthesiology and Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Daqing Ma
- Division of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea & Westminster Hospital, London, UK; Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
| | - Qiang Wang
- Department of Anaesthesiology and Center for Brain Science, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China.
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Pekna M, Siqin S, de Pablo Y, Stokowska A, Torinsson Naluai Å, Pekny M. Astrocyte Responses to Complement Peptide C3a are Highly Context-Dependent. Neurochem Res 2023; 48:1233-1241. [PMID: 36097103 PMCID: PMC10030406 DOI: 10.1007/s11064-022-03743-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 07/07/2022] [Accepted: 08/29/2022] [Indexed: 11/27/2022]
Abstract
Astrocytes perform a range of homeostatic and regulatory tasks that are critical for normal functioning of the central nervous system. In response to an injury or disease, astrocytes undergo a pronounced transformation into a reactive state that involves changes in the expression of many genes and dramatically changes astrocyte morphology and functions. This astrocyte reactivity is highly dependent on the initiating insult and pathological context. C3a is a peptide generated by the proteolytic cleavage of the third complement component. C3a has been shown to exert neuroprotective effects, stimulate neural plasticity and promote astrocyte survival but can also contribute to synapse loss, Alzheimer's disease type neurodegeneration and blood-brain barrier dysfunction. To test the hypothesis that C3a elicits differential effects on astrocytes depending on their reactivity state, we measured the expression of Gfap, Nes, C3ar1, C3, Ngf, Tnf and Il1b in primary mouse cortical astrocytes after chemical ischemia, after exposure to lipopolysaccharide (LPS) as well as in control naïve astrocytes. We found that C3a down-regulated the expression of Gfap, C3 and Nes in astrocytes after ischemia. Further, C3a increased the expression of Tnf and Il1b in naive astrocytes and the expression of Nes in astrocytes exposed to LPS but did not affect the expression of C3ar1 or Ngf. Jointly, these results provide the first evidence that the complement peptide C3a modulates the responses of astrocytes in a highly context-dependent manner.
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Affiliation(s)
- Marcela Pekna
- Laboratory of Regenerative Neuroimmunology, Department of Clinical Neuroscience, Center for Brain Repair, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 405 30, Göteborg, Sweden.
| | - Sumen Siqin
- Laboratory of Regenerative Neuroimmunology, Department of Clinical Neuroscience, Center for Brain Repair, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 405 30, Göteborg, Sweden
- Division of Episomal Persistent DNA in Cancer and Chronic Diseases, German Cancer Research Centre (DKFZ), 69120, Heidelberg, Germany
| | - Yolanda de Pablo
- Laboratory of Astrocyte Biology and CNS Regeneration, Department of Clinical Neuroscience, Center for Brain Repair, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 405 30, Göteborg, Sweden
| | - Anna Stokowska
- Laboratory of Regenerative Neuroimmunology, Department of Clinical Neuroscience, Center for Brain Repair, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 405 30, Göteborg, Sweden
| | - Åsa Torinsson Naluai
- Department of Laboratory Medicine, Institute of Biomedicine, Sahlgrenska Academy at the University of Gothenburg, Göteborg, Sweden
| | - Milos Pekny
- Laboratory of Astrocyte Biology and CNS Regeneration, Department of Clinical Neuroscience, Center for Brain Repair, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 405 30, Göteborg, Sweden.
- Florey Institute of Neuroscience and and Mental Health, Parkville, Melbourne, Australia.
- University of Newcastle, Newcastle, NSW, Australia.
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Gong B, Guo D, Zheng C, Ma Z, Zhang J, Qu Y, Li X, Li G, Zhang L, Wang Y. Complement C3a activates astrocytes to promote medulloblastoma progression through TNF-α. J Neuroinflammation 2022; 19:159. [PMID: 35725556 PMCID: PMC9208237 DOI: 10.1186/s12974-022-02516-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 06/05/2022] [Indexed: 12/16/2022] Open
Abstract
Background Medulloblastoma (MB) is the most common malignant brain tumor in children. Approximately one-third of MB patients remain incurable. Understanding the molecular mechanism of MB tumorigenesis is, therefore, critical for developing specific and effective treatment strategies. Our previous work demonstrated that astrocytes constitute the tumor microenvironment (TME) of MB and play an indispensable role in MB progression. However, the underlying mechanisms by which astrocytes are regulated and activated to promote MB remain elusive. Methods By taking advantage of Math1-Cre/Ptch1loxp/loxp mice, which spontaneously develop MB, primary MB cells and astrocytes were isolated and then subjected to administration and coculture in vitro. Immunohistochemistry was utilized to determine the presence of C3a in MB sections. MB cell proliferation was evaluated by immunofluorescent staining. GFAP and cytokine expression levels in C3a-stimulated astrocytes were assessed by immunofluorescent staining, western blotting, q-PCR and ELISA. C3a receptor and TNF-α receptor expression was determined by PCR and immunofluorescent staining. p38 MAPK pathway activation was detected by western blotting. Transplanted MB mice were treated with a C3a receptor antagonist or TNF-α receptor antagonist to investigate their role in MB progression in vivo. Results We found that complement C3a, a fragment released from intact complement C3 following complement activation, was enriched in both human and murine MB tumor tissue, and its receptor was highly expressed on tumor-associated astrocytes (TAAs). We demonstrated that C3a activated astrocytes and promoted MB cell proliferation via the p38 MAPK pathway. Moreover, we discovered that C3a upregulated the production of proinflammatory cytokines, such as IL-6 and TNF-α in astrocytes. Application of the conditioned medium of C3a-stimulated astrocytes promoted MB cell proliferation, which was abolished by preincubation with a TNF-α receptor antagonist, indicating a TNF-α-dependent event. Indeed, we further demonstrated that administration of a selective C3a receptor or TNF-α receptor antagonist to mice subcutaneously transplanted with MB suppressed tumor progression in vivo. Conclusions C3a was released during MB development. C3a triggered astrocyte activation and TNF-α production via the p38 pathway, which promoted MB cell proliferation. Our findings revealed the novel role of C3a-mediated TNF-α production by astrocytes in MB progression. These findings imply that targeting C3a and TNF-α may represent a potential novel therapeutic approach for human MB. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02516-9.
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Affiliation(s)
- Biao Gong
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Duancheng Guo
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Chaonan Zheng
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Zhen Ma
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Jie Zhang
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Yanghui Qu
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Xinhua Li
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Gen Li
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Li Zhang
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China.
| | - Yuan Wang
- Laboratory of Molecular Neuropathology, Pediatric Cancer Center, College of Pharmaceutical Sciences, Soochow University, Suzhou, China.
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Pozo-Rodrigálvarez A, Li Y, Stokowska A, Wu J, Dehm V, Sourkova H, Steinbusch H, Mallard C, Hagberg H, Pekny M, Pekna M. C3a Receptor Signaling Inhibits Neurodegeneration Induced by Neonatal Hypoxic-Ischemic Brain Injury. Front Immunol 2022; 12:768198. [PMID: 34975856 PMCID: PMC8718687 DOI: 10.3389/fimmu.2021.768198] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/04/2021] [Indexed: 11/13/2022] Open
Abstract
Hypoxic-ischemic neonatal encephalopathy due to perinatal asphyxia is the leading cause of brain injury in newborns. Clinical data suggest that brain inflammation induced by perinatal insults can persist for years. We previously showed that signaling through the receptor for complement peptide C3a (C3aR) protects against cognitive impairment induced by experimental perinatal asphyxia. To investigate the long-term neuropathological effects of hypoxic-ischemic injury to the developing brain and the role of C3aR signaling therein, we subjected wildtype mice, C3aR deficient mice, and mice expressing biologically active C3a in the CNS to mild hypoxic-ischemic brain injury on postnatal day 9. We found that such injury triggers neurodegeneration and pronounced reactive gliosis in the ipsilesional hippocampus both of which persist long into adulthood. Transgenic expression of C3a in reactive astrocytes reduced hippocampal neurodegeneration and reactive gliosis. In contrast, neurodegeneration and microglial cell density increased in mice lacking C3aR. Intranasal administration of C3a for 3 days starting 1 h after induction of hypoxia-ischemia reduced neurodegeneration and reactive gliosis in the hippocampus of wildtype mice. We conclude that neonatal hypoxic-ischemic brain injury leads to long-lasting neurodegeneration. This neurodegeneration is substantially reduced by treatment with C3aR agonists, conceivably through modulation of reactive gliosis.
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Affiliation(s)
- Andrea Pozo-Rodrigálvarez
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - YiXian Li
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Anna Stokowska
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Jingyun Wu
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.,Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Verena Dehm
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Hana Sourkova
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Harry Steinbusch
- Department of Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastrich, Netherlands.,Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Carina Mallard
- Centre of Perinatal Medicine & Health, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Hagberg
- Centre of Perinatal Medicine & Health, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Centre for the Developing Brain, King's College, London, United Kingdom
| | - Milos Pekny
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Marcela Pekna
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
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Pekna M, Stokowska A, Pekny M. Targeting Complement C3a Receptor to Improve Outcome After Ischemic Brain Injury. Neurochem Res 2021. [PMID: 34379293 DOI: 10.1007/s11064-021-03419-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 06/30/2021] [Accepted: 07/19/2021] [Indexed: 02/08/2023]
Abstract
Ischemic stroke is a major cause of disability. No efficient therapy is currently available, except for the removal of the occluding blood clot during the first hours after symptom onset. Loss of function after stroke is due to cell death in the infarcted tissue, cell dysfunction in the peri-infarct region, as well as dysfunction and neurodegeneration in remote brain areas. Plasticity responses in spared brain regions are a major contributor to functional recovery, while secondary neurodegeneration in remote regions is associated with depression and impedes the long-term outcome after stroke. Hypoxic-ischemic encephalopathy due to birth asphyxia is the leading cause of neurological disability resulting from birth complications. Despite major progress in neonatal care, approximately 50% of survivors develop complications such as mental retardation, cerebral palsy or epilepsy. The C3a receptor (C3aR) is expressed by many cell types including neurons and glia. While there is a body of evidence for its deleterious effects in the acute phase after ischemic injury to the adult brain, C3aR signaling contributes to better outcome in the post-acute and chronic phase after ischemic stroke in adults and in the ischemic immature brain. Here we discuss recent insights into the novel roles of C3aR signaling in the ischemic brain with focus on the therapeutic opportunities of modulating C3aR activity to improve the outcome after ischemic stroke and birth asphyxia.
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Pekna M, Pekny M. The Complement System: A Powerful Modulator and Effector of Astrocyte Function in the Healthy and Diseased Central Nervous System. Cells 2021; 10:cells10071812. [PMID: 34359981 PMCID: PMC8303424 DOI: 10.3390/cells10071812] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/08/2021] [Accepted: 07/14/2021] [Indexed: 12/11/2022] Open
Abstract
The complement system, an effector arm of the innate immune system that plays a critical role in tissue inflammation, the elimination of pathogens and the clearance of dead cells and cell debris, has emerged as a regulator of many processes in the central nervous system, including neural cell genesis and migration, control of synapse number and function, and modulation of glial cell responses. Complement dysfunction has also been put forward as a major contributor to neurological disease. Astrocytes are neuroectoderm-derived glial cells that maintain water and ionic homeostasis, and control cerebral blood flow and multiple aspects of neuronal functioning. By virtue of their expression of soluble as well as membrane-bound complement proteins and receptors, astrocytes are able to both send and receive complement-related signals. Here we review the current understanding of the multiple functions of the complement system in the central nervous system as they pertain to the modulation of astrocyte activity, and how astrocytes use the complement system to affect their environment in the healthy brain and in the context of neurological disease.
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Affiliation(s)
- Marcela Pekna
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, 40530 Gothenburg, Sweden
- Florey Institute of Neuroscience and Mental Health, Parkville, Melbourne 3010, Australia
- School of Medicine and Public Health, University of Newcastle, Newcastle 2308, Australia
- Correspondence: ; Tel.: +46-31-786-3581
| | - Milos Pekny
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, 40530 Gothenburg, Sweden;
- Florey Institute of Neuroscience and Mental Health, Parkville, Melbourne 3010, Australia
- School of Medicine and Public Health, University of Newcastle, Newcastle 2308, Australia
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Patabendige A, Singh A, Jenkins S, Sen J, Chen R. Astrocyte Activation in Neurovascular Damage and Repair Following Ischaemic Stroke. Int J Mol Sci 2021; 22:4280. [PMID: 33924191 PMCID: PMC8074612 DOI: 10.3390/ijms22084280] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 04/11/2021] [Accepted: 04/15/2021] [Indexed: 12/11/2022] Open
Abstract
Transient or permanent loss of tissue perfusion due to ischaemic stroke can lead to damage to the neurovasculature, and disrupt brain homeostasis, causing long-term motor and cognitive deficits. Despite promising pre-clinical studies, clinically approved neuroprotective therapies are lacking. Most studies have focused on neurons while ignoring the important roles of other cells of the neurovascular unit, such as astrocytes and pericytes. Astrocytes are important for the development and maintenance of the blood-brain barrier, brain homeostasis, structural support, control of cerebral blood flow and secretion of neuroprotective factors. Emerging data suggest that astrocyte activation exerts both beneficial and detrimental effects following ischaemic stroke. Activated astrocytes provide neuroprotection and contribute to neurorestoration, but also secrete inflammatory modulators, leading to aggravation of the ischaemic lesion. Astrocytes are more resistant than other cell types to stroke pathology, and exert a regulative effect in response to ischaemia. These roles of astrocytes following ischaemic stroke remain incompletely understood, though they represent an appealing target for neurovascular protection following stroke. In this review, we summarise the astrocytic contributions to neurovascular damage and repair following ischaemic stroke, and explore mechanisms of neuroprotection that promote revascularisation and neurorestoration, which may be targeted for developing novel therapies for ischaemic stroke.
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Affiliation(s)
- Adjanie Patabendige
- Brain Barriers Group, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2321, Australia;
- Priority Research Centre for Stroke and Brain Injury, and Priority Research Centre for Brain & Mental Health, University of Newcastle, Callaghan, NSW 2321, Australia
- Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
- Institute of Infection & Global Health, University of Liverpool, Liverpool L7 3EA, UK
| | - Ayesha Singh
- School of Pharmacy and Bioengineering, Keele University, Staffordshire ST5 5BG, UK;
| | - Stuart Jenkins
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (S.J.); (J.S.)
- Neural Tissue Engineering: Keele (NTEK), Keele University, Staffordshire ST5 5BG, UK
| | - Jon Sen
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (S.J.); (J.S.)
- Clinical Informatics and Neurosurgery Fellow, The Cleveland Clinic, 33 Grosvenor Square, London SW1X 7HY, UK
| | - Ruoli Chen
- School of Pharmacy and Bioengineering, Keele University, Staffordshire ST5 5BG, UK;
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Rojas-Colón LA, Dash PK, Morales-Vías FA, Lebrón-Dávila M, Ferchmin PA, Redell JB, Maldonado-Martínez G, Vélez-Torres WI. 4R-cembranoid confers neuroprotection against LPS-induced hippocampal inflammation in mice. J Neuroinflammation 2021; 18:95. [PMID: 33874954 PMCID: PMC8054431 DOI: 10.1186/s12974-021-02136-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 03/22/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Chronic brain inflammation has been implicated in the pathogenesis of various neurodegenerative diseases and disorders. For example, overexpression of pro-inflammatory cytokines has been associated with impairments in hippocampal-dependent memory. Lipopolysaccharide (LPS) injection is a widely used model to explore the pathobiology of inflammation. LPS injection into mice causes systemic inflammation, neuronal damage, and poor memory outcomes if the inflammation is not controlled. Activation of the alpha-7 nicotinic receptor (α7) plays an anti-inflammatory role in the brain through vagal efferent nerve signaling. 4R-cembranoid (4R) is a natural compound that crosses the blood-brain barrier, induces neuronal survival, and has been shown to modulate the activity of nicotinic receptors. The purpose of this study is to determine whether 4R reduces the deleterious effects of LPS-induced neuroinflammation and whether the α7 receptor plays a role in mediating these beneficial effects. METHODS Ex vivo population spike recordings were performed in C57BL/6J wild-type (WT) and alpha-7-knockout (α7KO) mouse hippocampal slices in the presence of 4R and nicotinic receptor inhibitors. For in vivo studies, WT and α7KO mice were injected with LPS for 2 h, followed by 4R or vehicle for 22 h. Analyses of IL-1β, TNF-α, STAT3, CREB, Akt1, and the long-term novel object recognition test (NORT) were performed for both genotypes. In addition, RNA sequencing and RT-qPCR analyses were carried out for 12 mRNAs related to neuroinflammation and their modification by 4R. RESULTS 4R confers neuroprotection after NMDA-induced neurotoxicity in both WT and α7KO mice. Moreover, hippocampal TNF-α and IL-1β levels were decreased with 4R treatment following LPS exposure in both strains of mice. 4R restored LPS-induced cognitive decline in NORT. There was a significant increase in the phosphorylation of STAT3, CREB, and Akt1 with 4R treatment in the WT mouse hippocampus following LPS exposure. In α7KO mice, only pAkt levels were significantly elevated in the cortex. 4R significantly upregulated mRNA levels of ORM2, GDNF, and C3 following LPS exposure. These proteins are known to play a role in modulating microglial activation, neuronal survival, and memory. CONCLUSION Our results indicate that 4R decreases the levels of pro-inflammatory cytokines; improves memory function; activates STAT3, Akt1, and CREB phosphorylation; and upregulates the mRNA levels of ORM2, GDNF, and C3. These effects are independent of the α7 nicotinic receptor.
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Affiliation(s)
- Luis A Rojas-Colón
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Av. Sta. Juanita, Bayamón, 00960, Puerto Rico
| | - Pramod K Dash
- Department of Neurobiology and Anatomy, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Fabiola A Morales-Vías
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Av. Sta. Juanita, Bayamón, 00960, Puerto Rico
| | - Madeline Lebrón-Dávila
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Av. Sta. Juanita, Bayamón, 00960, Puerto Rico
| | - Pedro A Ferchmin
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Av. Sta. Juanita, Bayamón, 00960, Puerto Rico
| | - John B Redell
- Department of Neurobiology and Anatomy, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Geronimo Maldonado-Martínez
- University of Puerto Rico Molecular Science Research Center, Av. Juan Ponce de León, San Juan, 00926, Puerto Rico
| | - Wanda I Vélez-Torres
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Av. Sta. Juanita, Bayamón, 00960, Puerto Rico.
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10
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Shinjyo N, Nakayama H, Li L, Ishimaru K, Hikosaka K, Suzuki N, Yoshida H, Norose K. Hypericum perforatum extract and hyperforin inhibit the growth of neurotropic parasite Toxoplasma gondii and infection-induced inflammatory responses of glial cells in vitro. J Ethnopharmacol 2021; 267:113525. [PMID: 33129946 DOI: 10.1016/j.jep.2020.113525] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 09/19/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Hypericum perforatum L. has been widely used as a natural antidepressant. However, it is unknown whether it is effective in treating infection-induced neuropsychiatric disorders. AIM OF THE STUDY In order to evaluate the effectiveness of H. perforatum against infection with neurotropic parasite Toxoplasma gondii, which has been linked to neuropsychiatric disorders, this study investigated the anti-Toxoplasma activity using in vitro models. MATERIALS AND METHODS Dried alcoholic extracts were prepared from three Hypericum species: H. perforatum, H. erectum, and H. ascyron. H. perforatum extract was further separated by solvent-partitioning. Hyperforin and hypericin levels in the extracts and fractions were analyzed by high resolution LC-MS. Anti-Toxoplasma activities were tested in vitro, using cell lines (Vero and Raw264), murine primary mixed glia, and primary neuron-glia. Toxoplasma proliferation and stage conversion were analyzed by qPCR. Infection-induced damages to the host cells were analyzed by Sulforhodamine B cytotoxicity assay (Vero) and immunofluorescent microscopy (neurons). Infection-induced inflammatory responses in glial cells were analysed by qPCR and immunofluorescent microscopy. RESULTS Hyperforin was identified only in H. perforatum among the three tested species, whereas hypericin was present in H. perforatum and H. erectum. H. perforatum extract and hyperforin-enriched fraction, as well as hyperforin, exhibited significant anti-Toxoplasma property as well as inhibitory activity against infection-induced inflammatory responses in glial cells. In addition, H. perforatum-derived hyperforin-enriched fraction restored neuro-supportive environment in mixed neuron-glia culture. CONCLUSIONS H. perforatum and its major constituent hyperforin are promising anti-Toxoplasma agents that could potentially protect neurons and glial cells against infection-induced damages. Further study is warranted to establish in vivo efficacy.
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Affiliation(s)
- Noriko Shinjyo
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan; School of Tropical Medicine and Global Health, Nagasaki University, 1-12-4, Sakamoto, Nagasaki, 852-8523, Japan.
| | - Hideyuki Nakayama
- Saga Prefectural Institute of Public Health and Pharmaceutical Research, 1-20 Hacchounawate, Saga, 849-0925, Japan
| | - Li Li
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan
| | - Kanji Ishimaru
- Department of Biological Resource Sciences, Faculty of Agriculture, Saga University, 1 Honjo, Saga, 840-8502, Japan
| | - Kenji Hikosaka
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan
| | - Noriyuki Suzuki
- Department of Toxicology and Environmental Health, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan
| | - Hiroki Yoshida
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga, 849-8501, Japan
| | - Kazumi Norose
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan
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11
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Pozo-Rodrigálvarez A, Ollaranta R, Skoog J, Pekny M, Pekna M. Hyperactive Behavior and Altered Brain Morphology in Adult Complement C3a Receptor Deficient Mice. Front Immunol 2021; 12:604812. [PMID: 33692783 PMCID: PMC7937871 DOI: 10.3389/fimmu.2021.604812] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 02/01/2021] [Indexed: 01/04/2023] Open
Abstract
The C3a receptor (C3aR) is a seven trans-membrane domain G-protein coupled receptor with a range of immune modulatory functions. C3aR is activated by the third complement component (C3) activation derived peptide C3a and a neuropeptide TLQP-21. In the central nervous system (CNS), C3aR is expressed by neural progenitors, neurons as well as glial cells. The non-immune functions of C3aR in the adult CNS include regulation of basal neurogenesis, injury-induced neural plasticity, and modulation of glial cell activation. In the developing brain, C3aR and C3 have been shown to play a role in neural progenitor cell proliferation and neuronal migration with potential implications for autism spectrum disorder, and adult C3aR deficient (C3aR−/−) mice were reported to exhibit subtle deficit in recall memory. Here, we subjected 3 months old male C3aR−/− mice to a battery of behavioral tests and examined their brain morphology. We found that the C3aR−/− mice exhibit a short-term memory deficit and increased locomotor activity, but do not show any signs of autistic behavior as assessed by self-grooming behavior. We also found regional differences between the C3aR−/− and wild-type (WT) mice in the morphology of motor and somatosensory cortex, as well as amygdala and hippocampus. In summary, constitutive absence of C3aR signaling in mice leads to neurodevelopmental abnormalities that persist into adulthood and are associated with locomotive hyperactivity and altered cognitive functions.
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Affiliation(s)
- Andrea Pozo-Rodrigálvarez
- Laboratory of Regenerative Neuroimmunology, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Roosa Ollaranta
- Laboratory of Regenerative Neuroimmunology, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Jenny Skoog
- Laboratory of Regenerative Neuroimmunology, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Milos Pekny
- Laboratory of Astrocyte Biology and CNS Regeneration, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.,Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,University of Newcastle, Newcastle, NSW, Australia
| | - Marcela Pekna
- Laboratory of Regenerative Neuroimmunology, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.,Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,University of Newcastle, Newcastle, NSW, Australia
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12
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Shinjyo N, Hikosaka K, Kido Y, Yoshida H, Norose K. Toxoplasma Infection Induces Sustained Up-Regulation of Complement Factor B and C5a Receptor in the Mouse Brain via Microglial Activation: Implication for the Alternative Complement Pathway Activation and Anaphylatoxin Signaling in Cerebral Toxoplasmosis. Front Immunol 2021; 11:603924. [PMID: 33613523 PMCID: PMC7892429 DOI: 10.3389/fimmu.2020.603924] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/21/2020] [Indexed: 01/01/2023] Open
Abstract
Toxoplasma gondii is a neurotropic protozoan parasite, which is linked to neurological manifestations in immunocompromised individuals as well as severe neurodevelopmental sequelae in congenital toxoplasmosis. While the complement system is the first line of host defense that plays a significant role in the prevention of parasite dissemination, Toxoplasma artfully evades complement-mediated clearance via recruiting complement regulatory proteins to their surface. On the other hand, the details of Toxoplasma and the complement system interaction in the brain parenchyma remain elusive. In this study, infection-induced changes in the mRNA levels of complement components were analyzed by quantitative PCR using a murine Toxoplasma infection model in vivo and primary glial cells in vitro. In addition to the core components C3 and C1q, anaphylatoxin C3a and C5a receptors (C3aR and C5aR1), as well as alternative complement pathway components properdin (CFP) and factor B (CFB), were significantly upregulated 2 weeks after inoculation. Two months post-infection, CFB, C3, C3aR, and C5aR1 expression remained higher than in controls, while CFP upregulation was transient. Furthermore, Toxoplasma infection induced significant increase in CFP, CFB, C3, and C5aR1 in mixed glial culture, which was abrogated when microglial activation was inhibited by pre-treatment with minocycline. This study sheds new light on the roles for the complement system in the brain parenchyma during Toxoplasma infection, which may lead to the development of novel therapeutic approaches to Toxoplasma infection-induced neurological disorders.
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MESH Headings
- Animals
- Brain/immunology
- Brain/metabolism
- Brain/parasitology
- Cells, Cultured
- Complement Factor B/genetics
- Complement Factor B/metabolism
- Complement Pathway, Alternative
- Disease Models, Animal
- Host-Parasite Interactions
- Male
- Mice, Inbred C57BL
- Microglia/immunology
- Microglia/metabolism
- Microglia/parasitology
- Receptor, Anaphylatoxin C5a/genetics
- Receptor, Anaphylatoxin C5a/metabolism
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Signal Transduction
- Time Factors
- Toxoplasma/immunology
- Toxoplasma/pathogenicity
- Toxoplasmosis, Animal/genetics
- Toxoplasmosis, Animal/immunology
- Toxoplasmosis, Animal/metabolism
- Toxoplasmosis, Animal/parasitology
- Toxoplasmosis, Cerebral/genetics
- Toxoplasmosis, Cerebral/immunology
- Toxoplasmosis, Cerebral/metabolism
- Toxoplasmosis, Cerebral/parasitology
- Up-Regulation
- Mice
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Affiliation(s)
- Noriko Shinjyo
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Japan
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
- Department of Parasitology & Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka City University, Osaka, Japan
| | - Kenji Hikosaka
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Yasutoshi Kido
- Department of Parasitology & Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka City University, Osaka, Japan
| | - Hiroki Yoshida
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga, Japan
| | - Kazumi Norose
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Japan
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13
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Abstract
The complement cascade is a critical effector mechanism of the innate immune system that contributes to the rapid clearance of pathogens and dead or dying cells, as well as contributing to the extent and limit of the inflammatory immune response. In addition, some of the early components of this cascade have been clearly shown to play a beneficial role in synapse elimination during the development of the nervous system, although excessive complement-mediated synaptic pruning in the adult or injured brain may be detrimental in multiple neurogenerative disorders. While many of these later studies have been in mouse models, observations consistent with this notion have been reported in human postmortem examination of brain tissue. Increasing awareness of distinct roles of C1q, the initial recognition component of the classical complement pathway, that are independent of the rest of the complement cascade, as well as the relationship with other signaling pathways of inflammation (in the periphery as well as the central nervous system), highlights the need for a thorough understanding of these molecular entities and pathways to facilitate successful therapeutic design, including target identification, disease stage for treatment, and delivery in specific neurologic disorders. Here, we review the evidence for both beneficial and detrimental effects of complement components and activation products in multiple neurodegenerative disorders. Evidence for requisite co-factors for the diverse consequences are reviewed, as well as the recent studies that support the possibility of successful pharmacological approaches to suppress excessive and detrimental complement-mediated chronic inflammation, while preserving beneficial effects of complement components, to slow the progression of neurodegenerative disease.
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Affiliation(s)
- Nicole D. Schartz
- Department of Molecular Biology and Biochemistry, University of California Irvine, 3205 McGaugh Hall, Irvine, CA 92697 USA
| | - Andrea J. Tenner
- Department of Molecular Biology and Biochemistry, University of California Irvine, 3205 McGaugh Hall, Irvine, CA 92697 USA
- Department of Neurobiology and Behavior, University of California Irvine, 3205 McGaugh Hall, Irvine, CA 92697 USA
- Department of Pathology and Laboratory Medicine, University of California Irvine, 3205 McGaugh Hall, Irvine, CA 92697 USA
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14
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Zheng JM, Wang SS, Tian X, Che DJ. Sustained activation of C3aR in a human podocyte line impairs the morphological maturation of the cells. Mol Med Rep 2020; 22:5326-5338. [PMID: 33174024 PMCID: PMC7646996 DOI: 10.3892/mmr.2020.11626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 09/02/2020] [Indexed: 12/03/2022] Open
Abstract
The C3a receptor (C3aR) has been reported to be involved in various physiological and pathological processes, including the regulation of cellular structure development. Expression of C3aR has been reported in podocytes; however, data concerning the role of C3aR in podocyte morphology is scarce. The aim of the present study was to examine the effect of C3aR activation on the architectural development of podocytes. An immortal human podocyte line (HPC) was transfected with a C3a expression lentivirus vector or recombinant C3a. SB290157 was used to block the activation of C3aR. The expression of C3a in HPC cells was analyzed by reverse transcription-quantitative PCR (RT-qPCR) and ELISAs. Phase contrast and fluorescence microscopy were used to observe the morphology of the podocytes. The adhesive ability of HPC cells was analyzed using an attachment assay. RT-qPCR, cyto-immunofluorescence and western blotting were used to determine the expression levels of the adhesion-associated genes. The expression levels of carboxypeptidases in HPC cells was also detected by RT-qPCR. Compared with the untransfected and control virus-transfected HPC cells, the C3a-overexpressing cells (HPC-C3a) failed to expand their cell bodies and develop an arborized appearance in the process of maturation, which the control cells exhibited. In addition, HPC-C3a cells presented with decreased adhesive capacity, altered focal adhesion (FA) plaques and decreased expression of FA-associated genes. These effects were blocked by a C3aR antagonist; however, the addition of purified C3a could not completely mimic the effects of C3a overexpression. Furthermore, HPC cells expressed carboxypeptidases, which have been reported to be able to inactivate C3a. In summary, the results demonstrated that sustained C3aR activation impaired the morphological maturation of HPC cells, which may be associated with the altered expression of FA-associated genes and impaired FA. Since chronic complement activation has been reported in renal diseases, which indicate sustained C3aR activation in renal cells, including podocytes and podocyte progenitors, the possible role of C3aR in the dysregulation of podocyte architecture and podocyte regeneration requires further research.
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Affiliation(s)
- Jing-Min Zheng
- Department of Nephrology, Taizhou Hospital, Wenzhou Medical University, Linhai, Zhejiang 317000, P.R. China
| | - Sha-Sha Wang
- Department of Nephrology, Taizhou Hospital, Wenzhou Medical University, Linhai, Zhejiang 317000, P.R. China
| | - Xiong Tian
- Department of Nephrology, Taizhou Hospital, Wenzhou Medical University, Linhai, Zhejiang 317000, P.R. China
| | - De-Jun Che
- Department of Nephrology, Taizhou Hospital, Wenzhou Medical University, Linhai, Zhejiang 317000, P.R. China
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15
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Tonon MC, Vaudry H, Chuquet J, Guillebaud F, Fan J, Masmoudi-Kouki O, Vaudry D, Lanfray D, Morin F, Prevot V, Papadopoulos V, Troadec JD, Leprince J. Endozepines and their receptors: Structure, functions and pathophysiological significance. Pharmacol Ther 2020; 208:107386. [DOI: 10.1016/j.pharmthera.2019.06.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 06/20/2019] [Indexed: 02/06/2023]
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16
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Abstract
Ischemic stroke, which accounts for 75-80% of all strokes, is the predominant cause of morbidity and mortality worldwide. The post-stroke immune response has recently emerged as a new breakthrough target in the treatment strategy for ischemic stroke. Glial cells, including microglia, astrocytes, and oligodendrocytes, are the primary components of the peri-infarct environment in the central nervous system (CNS) and have been implicated in post-stroke immune regulation. However, increasing evidence suggests that glial cells exert beneficial and detrimental effects during ischemic stroke. Microglia, which survey CNS homeostasis and regulate innate immune responses, are rapidly activated after ischemic stroke. Activated microglia release inflammatory cytokines that induce neuronal tissue injury. By contrast, anti-inflammatory cytokines and neurotrophic factors secreted by alternatively activated microglia are beneficial for recovery after ischemic stroke. Astrocyte activation and reactive gliosis in ischemic stroke contribute to limiting brain injury and re-establishing CNS homeostasis. However, glial scarring hinders neuronal reconnection and extension. Neuroinflammation affects the demyelination and remyelination of oligodendrocytes. Myelin-associated antigens released from oligodendrocytes activate peripheral T cells, thereby resulting in the autoimmune response. Oligodendrocyte precursor cells, which can differentiate into oligodendrocytes, follow an ischemic stroke and may result in functional recovery. Herein, we discuss the mechanisms of post-stroke immune regulation mediated by glial cells and the interaction between glial cells and neurons. In addition, we describe the potential roles of various glial cells at different stages of ischemic stroke and discuss future intervention targets.
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Affiliation(s)
- Shenbin Xu
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jianan Lu
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Anwen Shao
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - John H Zhang
- Department of Physiology and Pharmacology, School of Medicine, Loma Linda University, Loma Linda, CA, United States.,Department of Anesthesiology, School of Medicine, Loma Linda University, Loma Linda, CA, United States.,Department of Neurosurgery, School of Medicine, Loma Linda University, Loma Linda, CA, United States
| | - Jianmin Zhang
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Brain Research Institute, Zhejiang University, Hangzhou, China.,Collaborative Innovation Center for Brain Science, Zhejiang University, Hangzhou, China
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17
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Woo JJ, Pouget JG, Zai CC, Kennedy JL. The complement system in schizophrenia: where are we now and what's next? Mol Psychiatry 2020; 25:114-130. [PMID: 31439935 DOI: 10.1038/s41380-019-0479-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 02/06/2019] [Accepted: 02/11/2019] [Indexed: 12/24/2022]
Abstract
The complement system is a set of immune proteins involved in first-line defense against pathogens and removal of waste materials. Recent evidence has implicated the complement cascade in diseases involving the central nervous system, including schizophrenia. Here, we provide an up-to-date narrative review and critique of the literature on the relationship between schizophrenia and complement gene polymorphisms, gene expression, protein concentration, and pathway activity. A literature search identified 23 new studies since the first review on this topic in 2008. Overall complement pathway activity appears to be elevated in schizophrenia. Recent studies have identified complement component 4 (C4) and CUB and Sushi Multiple Domains 1 (CSMD1) as potential genetic markers of schizophrenia. In particular, there is some evidence of higher rates of C4B/C4S deficiency, reduced peripheral C4B concentration, and elevated brain C4A mRNA expression in schizophrenia patients compared to controls. To better elucidate the additive effects of multiple complement genotypes, we also conducted gene- and gene-set analysis through MAGMA which supported the role of Human Leukocyte Antigen class (HLA) III genes and, to a lesser extent, CSMD1 in schizophrenia; however, the HLA-schizophrenia association was likely driven by the C4 gene. Lastly, we identified several limitations of the literature on the complement system and schizophrenia, including: small sample sizes, inconsistent methodologies, limited measurements of neural concentrations of complement proteins, little exploration of the link between complement and schizophrenia phenotype, and lack of studies exploring schizophrenia treatment response. Overall, recent findings highlight complement components-in particular, C4 and CSMD1-as potential novel drug targets in schizophrenia. Given the growing availability of complement-targeted therapies, future clinical studies evaluating their efficacy in schizophrenia hold the potential to accelerate treatment advances.
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Affiliation(s)
- Julia J Woo
- Tanenbaum Centre for Pharmacogenetics, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada
| | - Jennie G Pouget
- Tanenbaum Centre for Pharmacogenetics, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada
| | - Clement C Zai
- Tanenbaum Centre for Pharmacogenetics, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada
| | - James L Kennedy
- Tanenbaum Centre for Pharmacogenetics, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada.
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18
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de Pablo Y, Marasek P, Pozo-Rodrigálvarez A, Wilhelmsson U, Inagaki M, Pekna M, Pekny M. Vimentin Phosphorylation Is Required for Normal Cell Division of Immature Astrocytes. Cells 2019; 8:cells8091016. [PMID: 31480524 PMCID: PMC6769829 DOI: 10.3390/cells8091016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/20/2019] [Accepted: 08/28/2019] [Indexed: 12/17/2022] Open
Abstract
Vimentin (VIM) is an intermediate filament (nanofilament) protein expressed in multiple cell types, including astrocytes. Mice with VIM mutations of serine sites phosphorylated during mitosis (VIMSA/SA) show cytokinetic failure in fibroblasts and lens epithelial cells, chromosomal instability, facilitated cell senescence, and increased neuronal differentiation of neural progenitor cells. Here we report that in vitro immature VIMSA/SA astrocytes exhibit cytokinetic failure and contain vimentin accumulations that co-localize with mitochondria. This phenotype is transient and disappears with VIMSA/SA astrocyte maturation and expression of glial fibrillary acidic protein (GFAP); it is also alleviated by the inhibition of cell proliferation. To test the hypothesis that GFAP compensates for the effect of VIMSA/SA in astrocytes, we crossed the VIMSA/SA and GFAP−/− mice. Surprisingly, the fraction of VIMSA/SA immature astrocytes with abundant vimentin accumulations was reduced when on GFAP−/− background. This indicates that the disappearance of vimentin accumulations and cytokinetic failure in mature astrocyte cultures are independent of GFAP expression. Both VIMSA/SA and VIMSA/SAGFAP−/− astrocytes showed normal mitochondrial membrane potential and vulnerability to H2O2, oxygen/glucose deprivation, and chemical ischemia. Thus, mutation of mitotic phosphorylation sites in vimentin triggers formation of vimentin accumulations and cytokinetic failure in immature astrocytes without altering their vulnerability to oxidative stress.
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Affiliation(s)
- Yolanda de Pablo
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, 40530 Gothenburg, Sweden
| | - Pavel Marasek
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, 40530 Gothenburg, Sweden
| | - Andrea Pozo-Rodrigálvarez
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, 40530 Gothenburg, Sweden
| | - Ulrika Wilhelmsson
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, 40530 Gothenburg, Sweden
| | - Masaki Inagaki
- Department of Physiology, Mie University Graduate School of Medicine, Mie 5148507, Japan
| | - Marcela Pekna
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, 40530 Gothenburg, Sweden
- Florey Institute of Neuroscience and Mental Health, Parkville, Victoria 3052, Australia
- University of Newcastle, New South Wales 2308, Australia
| | - Milos Pekny
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, 40530 Gothenburg, Sweden.
- Florey Institute of Neuroscience and Mental Health, Parkville, Victoria 3052, Australia.
- University of Newcastle, New South Wales 2308, Australia.
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19
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Clarke AR, Christophe BR, Khahera A, Sim JL, Connolly ES. Therapeutic Modulation of the Complement Cascade in Stroke. Front Immunol 2019; 10:1723. [PMID: 31417544 PMCID: PMC6682670 DOI: 10.3389/fimmu.2019.01723] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/09/2019] [Indexed: 01/22/2023] Open
Abstract
Stroke is a leading cause of death and disability worldwide and an increasing number of ischemic stroke patients are undergoing pharmacological and mechanical reperfusion. Both human and experimental models of reperfused ischemic stroke have implicated the complement cascade in secondary tissue injury. Most data point to the lectin and alternative pathways as key to activation, and C3a and C5a binding of their receptors as critical effectors of injury. During periods of thrombolysis use to treat stroke, acute experimental complement cascade blockade has been found to rescue tissue and improves functional outcome. Blockade of the complement cascade during the period of tissue reorganization, repair, and recovery is by contrast not helpful and in fact is likely to be deleterious with emerging data suggesting downstream upregulation of the cascade might even facilitate recovery. Successful clinical translation will require the right clinical setting and pharmacologic strategies that are capable of targeting the key effectors early while not inhibiting delayed repair. Early reports in a variety of disease states suggest that such pharmacologic strategies appear to have a favorable risk profile and offer substantial hope for patients.
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Affiliation(s)
- Alison R Clarke
- Cerebrovascular Research Laboratory, Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY, United States
| | - Brandon R Christophe
- Cerebrovascular Research Laboratory, Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY, United States
| | - Anadjeet Khahera
- Cerebrovascular Research Laboratory, Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY, United States
| | - Justin L Sim
- Cerebrovascular Research Laboratory, Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY, United States
| | - E Sander Connolly
- Cerebrovascular Research Laboratory, Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY, United States
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20
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Ma Y, Liu Y, Zhang Z, Yang GY. Significance of Complement System in Ischemic Stroke: A Comprehensive Review. Aging Dis 2019; 10:429-462. [PMID: 31011487 PMCID: PMC6457046 DOI: 10.14336/ad.2019.0119] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/19/2019] [Indexed: 12/14/2022] Open
Abstract
The complement system is an essential part of innate immunity, typically conferring protection via eliminating pathogens and accumulating debris. However, the defensive function of the complement system can exacerbate immune, inflammatory, and degenerative responses in various pathological conditions. Cumulative evidence indicates that the complement system plays a critical role in the pathogenesis of ischemic brain injury, as the depletion of certain complement components or the inhibition of complement activation could reduce ischemic brain injury. Although multiple candidates modulating or inhibiting complement activation show massive potential for the treatment of ischemic stroke, the clinical availability of complement inhibitors remains limited. The complement system is also involved in neural plasticity and neurogenesis during cerebral ischemia. Thus, unexpected side effects could be induced if the systemic complement system is inhibited. In this review, we highlighted the recent concepts and discoveries of the roles of different kinds of complement components, such as C3a, C5a, and their receptors, in both normal brain physiology and the pathophysiology of brain ischemia. In addition, we comprehensively reviewed the current development of complement-targeted therapy for ischemic stroke and discussed the challenges of bringing these therapies into the clinic. The design of future experiments was also discussed to better characterize the role of complement in both tissue injury and recovery after cerebral ischemia. More studies are needed to elucidate the molecular and cellular mechanisms of how complement components exert their functions in different stages of ischemic stroke to optimize the intervention of targeting the complement system.
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Affiliation(s)
- Yuanyuan Ma
- 1Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Yanqun Liu
- 3Department of Neurology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Zhijun Zhang
- 2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Guo-Yuan Yang
- 1Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
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21
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Yin P, Wei Y, Wang X, Zhu M, Feng J. Roles of Specialized Pro-Resolving Lipid Mediators in Cerebral Ischemia Reperfusion Injury. Front Neurol 2018; 9:617. [PMID: 30131754 PMCID: PMC6090140 DOI: 10.3389/fneur.2018.00617] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 07/10/2018] [Indexed: 12/14/2022] Open
Abstract
Ischemic stroke contributes to ~80% of all stroke cases. Recanalization with thrombolysis or endovascular thrombectomy are currently critical therapeutic strategies for rebuilding the blood supply following ischemic stroke. However, recanalization is often accompanied by cerebral ischemia reperfusion injury that is mediated by oxidative stress and inflammation. Resolution of inflammation belongs to the end stage of inflammation where inflammation is terminated and the repair of damaged tissue is started. Resolution of inflammation is mediated by a group of newly discovered lipid mediators called specialized pro-resolving lipid mediators (SPMs). Accumulating evidence suggests that SPMs decrease leukocyte infiltration, enhance efferocytosis, reduce local neuronal injury, and decrease both oxidative stress and the production of inflammatory cytokines in various in vitro and in vivo models of ischemic stroke. In this review, we summarize the mechanisms of reperfusion injury and the various roles of SPMs in stroke therapy.
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Affiliation(s)
- Ping Yin
- Department of Neurology and Neuroscience Center, First Hospital of Jilin University, Changchun, China.,First Department of Neurology and Neuroscience Center, Heilongjiang Provincial Hospital, Harbin, China
| | - Yafen Wei
- First Department of Neurology and Neuroscience Center, Heilongjiang Provincial Hospital, Harbin, China
| | - Xu Wang
- Department of Neurology and Neuroscience Center, First Hospital of Jilin University, Changchun, China
| | - Mingqin Zhu
- Department of Neurology and Neuroscience Center, First Hospital of Jilin University, Changchun, China
| | - Jiachun Feng
- Department of Neurology and Neuroscience Center, First Hospital of Jilin University, Changchun, China
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22
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Pekny M, Wilhelmsson U, Tatlisumak T, Pekna M. Astrocyte activation and reactive gliosis-A new target in stroke? Neurosci Lett 2018; 689:45-55. [PMID: 30025833 DOI: 10.1016/j.neulet.2018.07.021] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 07/03/2018] [Accepted: 07/14/2018] [Indexed: 11/27/2022]
Abstract
Stroke is an acute insult to the central nervous system (CNS) that triggers a sequence of responses in the acute, subacute as well as later stages, with prominent involvement of astrocytes. Astrocyte activation and reactive gliosis in the acute stage of stroke limit the tissue damage and contribute to the restoration of homeostasis. Astrocytes also control many aspects of neural plasticity that is the basis for functional recovery. Here, we discuss the concept of intermediate filaments (nanofilaments) and the complement system as two handles on the astrocyte responses to injury that both present attractive opportunities for novel treatment strategies modulating astrocyte functions and reactive gliosis.
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Affiliation(s)
- Milos Pekny
- Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530 Gothenburg, Sweden; Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia; University of Newcastle, Newcastle, NSW, Australia.
| | - Ulrika Wilhelmsson
- Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530 Gothenburg, Sweden
| | - Turgut Tatlisumak
- Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530 Gothenburg, Sweden; Department of Neurology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Marcela Pekna
- Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530 Gothenburg, Sweden; Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia; University of Newcastle, Newcastle, NSW, Australia
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23
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Gao M, Dong Q, Lu Y, Yao H, Zou M, Yang Y, Zhu J, Yang Z, Xu M, Xu R. Induced neural stem cell-derived astrocytes modulate complement activation and mediate neuroprotection following closed head injury. Cell Death Dis 2018; 9:101. [PMID: 29367701 DOI: 10.1038/s41419-017-0172-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 10/25/2017] [Accepted: 11/22/2017] [Indexed: 11/09/2022]
Abstract
The complement system is a crucial component of immunity, and its activation has critical roles in neuroinflammatory response and cellular damage following closed head injury (CHI). We previously demonstrated that systemically injected induced neural stem cells (iNSCs) could modulate complement activation to ameliorate neuronal apoptosis in mouse CHI models. However, it remains unknown whether iNSC derivatives can regulate complement activation. In the present study, after CHI mouse serum treatment, we found dramatic decreases in the cellular viabilities of differentiated iNSCs. Interestingly, following CHI mouse serum treatment, the death of astrocytes derived from iNSCs which were pre-treated with CHI mouse serum was significantly decreased. Meanwhile, the deposition of C3 (C3d) and C5b-9 in these astrocytes was substantially reduced. Remarkably, we detected increased expression of complement receptor type 1-related protein y (Crry) in these astrocytes. Moreover, these astrocytes could reduce the numbers of apoptotic neurons via Crry expression post-CHI mouse serum treatment. Additionally, intracerebral-transplanted iNSCs, pre-treated with CHI mouse serum, significantly increased the levels of Crry expression in astrocytes to reduce the accumulation of C3d and C9 and the death of neurons in the brains of CHI mice. In summary, iNSCs receiving CHI mouse serum pre-treatment could enhance the expression of Crry in iNSC-derived astrocytes to modulate complement activation and mediate neuroprotection following CHI.
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24
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Abstract
Astrocytes are neural cells of ectodermal, neuroepithelial origin that provide for homeostasis and defense of the central nervous system (CNS). Astrocytes are highly heterogeneous in morphological appearance; they express a multitude of receptors, channels, and membrane transporters. This complement underlies their remarkable adaptive plasticity that defines the functional maintenance of the CNS in development and aging. Astrocytes are tightly integrated into neural networks and act within the context of neural tissue; astrocytes control homeostasis of the CNS at all levels of organization from molecular to the whole organ.
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Affiliation(s)
- Alexei Verkhratsky
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
| | - Maiken Nedergaard
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
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25
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Reginia A, Kucharska-Mazur J, Jabłoński M, Budkowska M, Dołȩgowska B, Sagan L, Misiak B, Ratajczak MZ, Rybakowski JK, Samochowiec J. Assessment of Complement Cascade Components in Patients With Bipolar Disorder. Front Psychiatry 2018; 9:614. [PMID: 30538645 PMCID: PMC6277457 DOI: 10.3389/fpsyt.2018.00614] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 11/01/2018] [Indexed: 12/14/2022] Open
Abstract
Introduction: The immune system is undoubtedly involved in the pathogenesis of various psychiatric disorders, such as schizophrenia, bipolar disorder, or depression. Although its role is not fully understood, it appears that this area of research can help to understand the etiology of mental illness. One of the components of the human immune system is the complement system, which forms a part of the innate immune response. Physiologically, except for its essential protective role, it is a vital element in the regeneration processes, including neurogenesis. To date, few studies have tried to clarify the role of the complement cascade in mental disorders. Materials and Methods: We evaluated concentrations of C3a, C5a, and C5b-9 complement cascade components in the peripheral blood of 30 patients suffering from bipolar disorder (BD) for at least 10 years, in euthymia, who were not treated with lithium salts. In addition, we divided our study sample into BD type I (BD-I, 22 persons), and BD type II (BD-II, 8 patients). The control group consisted of 30 healthy volunteers matched for age, sex, BMI, and smoking habits. Results: Compared to healthy controls, BD patients had elevated concentrations of all the investigated components. Furthermore, in patients with BD-II, we observed higher concentrations of C5b-9 as compared to patients with BD-I. However, there was a significant effect of BD diagnosis only on the levels of C3a and C5a but not on the level of C5b-9 after adjustment for potential confounding factors. Conclusions: Increased concentrations of components C3a and C5a of the complement system in the investigated group as compared to healthy controls suggest involvement of the complement cascade in the pathogenesis of BD, and provides further evidence of immune system dysregulation in BD patients.
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Affiliation(s)
- Artur Reginia
- Department of Psychiatry, Pomeranian Medical University, Szczecin, Poland
| | | | - Marcin Jabłoński
- Department of Psychiatry, Pomeranian Medical University, Szczecin, Poland
| | - Marta Budkowska
- Department of Medical Analytics, Pomeranian Medical University, Szczecin, Poland
| | - Barbara Dołȩgowska
- Department of Laboratory Medicine, Pomeranian Medical University, Szczecin, Poland
| | - Leszek Sagan
- Department of Neurosurgery, Pomeranian Medical University, Szczecin, Poland
| | - Błazej Misiak
- Department of Genetics, Wroclaw Medical University, Wrocław, Poland
| | - Mariusz Z Ratajczak
- Stem Cell Institute at James Graham Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - Janusz K Rybakowski
- Department of Adult Psychiatry, Poznan University of Medical Sciences, Poznan, Poland
| | - Jerzy Samochowiec
- Department of Psychiatry, Pomeranian Medical University, Szczecin, Poland
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26
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Abstract
Astrocytes are neural cells of ectodermal, neuroepithelial origin that provide for homeostasis and defense of the central nervous system (CNS). Astrocytes are highly heterogeneous in morphological appearance; they express a multitude of receptors, channels, and membrane transporters. This complement underlies their remarkable adaptive plasticity that defines the functional maintenance of the CNS in development and aging. Astrocytes are tightly integrated into neural networks and act within the context of neural tissue; astrocytes control homeostasis of the CNS at all levels of organization from molecular to the whole organ.
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Affiliation(s)
- Alexei Verkhratsky
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
| | - Maiken Nedergaard
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
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27
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Chen M, Puschmann TB, Marasek P, Inagaki M, Pekna M, Wilhelmsson U, Pekny M. Increased Neuronal Differentiation of Neural Progenitor Cells Derived from Phosphovimentin-Deficient Mice. Mol Neurobiol 2017; 55:5478-5489. [PMID: 28956310 PMCID: PMC5994207 DOI: 10.1007/s12035-017-0759-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Accepted: 08/27/2017] [Indexed: 01/06/2023]
Abstract
Vimentin is an intermediate filament (also known as nanofilament) protein expressed in several cell types of the central nervous system, including astrocytes and neural stem/progenitor cells. Mutation of the vimentin serine sites that are phosphorylated during mitosis (VIMSA/SA) leads to cytokinetic failures in fibroblasts and lens epithelial cells, resulting in chromosomal instability and increased expression of cell senescence markers. In this study, we investigated morphology, proliferative capacity, and motility of VIMSA/SA astrocytes, and their effect on the differentiation of neural stem/progenitor cells. VIMSA/SA astrocytes expressed less vimentin and more GFAP but showed a well-developed intermediate filament network, exhibited normal cell morphology, proliferation, and motility in an in vitro wound closing assay. Interestingly, we found a two- to fourfold increased neuronal differentiation of VIMSA/SA neurosphere cells, both in a standard 2D and in Bioactive3D cell culture systems, and determined that this effect was neurosphere cell autonomous and not dependent on cocultured astrocytes. Using BrdU in vivo labeling to assess neural stem/progenitor cell proliferation and differentiation in the hippocampus of adult mice, one of the two major adult neurogenic regions, we found a modest increase (by 8%) in the fraction of newly born and surviving neurons. Thus, mutation of the serine sites phosphorylated in vimentin during mitosis alters intermediate filament protein expression but has no effect on astrocyte morphology or proliferation, and leads to increased neuronal differentiation of neural progenitor cells.
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Affiliation(s)
- Meng Chen
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530, Gothenburg, Sweden
| | - Till B Puschmann
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530, Gothenburg, Sweden
| | - Pavel Marasek
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530, Gothenburg, Sweden
| | - Masaki Inagaki
- Department of Physiology, Mie University Graduate School of Medicine, Mie, Japan
| | - Marcela Pekna
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.,Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,University of Newcastle, Newcastle, NSW, Australia
| | - Ulrika Wilhelmsson
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530, Gothenburg, Sweden
| | - Milos Pekny
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Box 440, 40530, Gothenburg, Sweden. .,Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia. .,University of Newcastle, Newcastle, NSW, Australia.
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28
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Hooshmand MJ, Nguyen HX, Piltti KM, Benavente F, Hong S, Flanagan L, Uchida N, Cummings BJ, Anderson AJ. Neutrophils Induce Astroglial Differentiation and Migration of Human Neural Stem Cells via C1q and C3a Synthesis. J Immunol 2017; 199:1069-1085. [PMID: 28687659 DOI: 10.4049/jimmunol.1600064] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/31/2017] [Indexed: 12/23/2022]
Abstract
Inflammatory processes play a key role in pathophysiology of many neurologic diseases/trauma, but the effect of immune cells and factors on neurotransplantation strategies remains unclear. We hypothesized that cellular and humoral components of innate immunity alter fate and migration of human neural stem cells (hNSC). In these experiments, conditioned media collected from polymorphonuclear leukocytes (PMN) selectively increased hNSC astrogliogenesis and promoted cell migration in vitro. PMN were shown to generate C1q and C3a; exposure of hNSC to PMN-synthesized concentrations of these complement proteins promoted astrogliogenesis and cell migration. Furthermore, in vitro, Abs directed against C1q and C3a reversed the fate and migration effects observed. In a proof-of-concept in vivo experiment, blockade of C1q and C3a transiently altered hNSC migration and reversed astroglial fate after spinal cord injury. Collectively, these data suggest that modulation of the innate/humoral inflammatory microenvironment may impact the potential of cell-based therapies for recovery and repair following CNS pathology.
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Affiliation(s)
- Mitra J Hooshmand
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697; .,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697.,Department of Anatomy and Neurobiology, University of California, Irvine, Irvine, CA 92697
| | - Hal X Nguyen
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697.,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697.,Department of Physical Medicine and Rehabilitation, University of California, Irvine, Irvine, CA 92697
| | - Katja M Piltti
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697.,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697.,Department of Anatomy and Neurobiology, University of California, Irvine, Irvine, CA 92697
| | - Francisca Benavente
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697.,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697.,Department of Anatomy and Neurobiology, University of California, Irvine, Irvine, CA 92697
| | - Samuel Hong
- Bridges to Stem Cell Research Program, California State University, Fullerton, Fullerton, CA 92834; and
| | - Lisa Flanagan
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697
| | | | - Brian J Cummings
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697.,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697.,Department of Anatomy and Neurobiology, University of California, Irvine, Irvine, CA 92697.,Department of Physical Medicine and Rehabilitation, University of California, Irvine, Irvine, CA 92697
| | - Aileen J Anderson
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697.,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697.,Department of Anatomy and Neurobiology, University of California, Irvine, Irvine, CA 92697.,Department of Physical Medicine and Rehabilitation, University of California, Irvine, Irvine, CA 92697
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29
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Liu X, Wang X, Li R, Jia S, Sun P, Zhao M, Fang C. Recent progress in the understanding of complement activation and its role in tumor growth and anti-tumor therapy. Biomed Pharmacother 2017; 91:446-56. [DOI: 10.1016/j.biopha.2017.04.101] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 04/18/2017] [Accepted: 04/23/2017] [Indexed: 02/07/2023] Open
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30
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Morán J, Stokowska A, Walker FR, Mallard C, Hagberg H, Pekna M. Intranasal C3a treatment ameliorates cognitive impairment in a mouse model of neonatal hypoxic-ischemic brain injury. Exp Neurol 2017; 290:74-84. [PMID: 28062175 DOI: 10.1016/j.expneurol.2017.01.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 12/12/2016] [Accepted: 01/02/2017] [Indexed: 10/20/2022]
Abstract
Perinatal asphyxia-induced brain injury is often associated with irreversible neurological complications such as intellectual disability and cerebral palsy but available therapies are limited. Novel neuroprotective therapies as well as approaches stimulating neural plasticity mechanism that can compensate for cell death after hypoxia-ischemia (HI) are urgently needed. We previously reported that single i.c.v. injection of complement-derived peptide C3a 1h after HI induction prevented HI-induced cognitive impairment when mice were tested as adults. Here, we tested the effects of intranasal treatment with C3a on HI-induced cognitive deficit. Using the object recognition test, we found that intranasal C3a treated mice were protected from HI-induced impairment of memory function assessed 6weeks after HI induction. C3a treatment ameliorated HI-induced reactive gliosis in the hippocampus, while it did not affect the extent of hippocampal tissue loss, neuronal cell density, expression of the pan-synaptic marker synapsin I or the expression of growth associated protein 43. In conclusion, our results reveal that brief pharmacological treatment with C3a using a clinically feasible non-invasive mode of administration ameliorates HI-induced cognitive impairment. Intranasal administration is a plausible route to deliver C3a into the brain of asphyxiated infants at high risk of developing hypoxic-ischemic encephalopathy.
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Affiliation(s)
- Javier Morán
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Anna Stokowska
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Frederik R Walker
- School of Biomedical Sciences and Pharmacy, University of Newcastle, New South Wales, Australia
| | - Carina Mallard
- Perinatal Center, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Hagberg
- Perinatal Center, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Centre for the Developing Brain, King's College, London, UK; Department of Obstetrics and Gynecology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Marcela Pekna
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia; Hunter Medical Research Institute, University of Newcastle, New South Wales, Australia.
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31
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Stokowska A, Atkins AL, Morán J, Pekny T, Bulmer L, Pascoe MC, Barnum SR, Wetsel RA, Nilsson JA, Dragunow M, Pekna M. Complement peptide C3a stimulates neural plasticity after experimental brain ischaemia. Brain 2016; 140:353-369. [PMID: 27956400 DOI: 10.1093/brain/aww314] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 10/19/2016] [Accepted: 10/20/2016] [Indexed: 11/12/2022] Open
Abstract
Ischaemic stroke induces endogenous repair processes that include proliferation and differentiation of neural stem cells and extensive rewiring of the remaining neural connections, yet about 50% of stroke survivors live with severe long-term disability. There is an unmet need for drug therapies to improve recovery by promoting brain plasticity in the subacute to chronic phase after ischaemic stroke. We previously showed that complement-derived peptide C3a regulates neural progenitor cell migration and differentiation in vitro and that C3a receptor signalling stimulates neurogenesis in unchallenged adult mice. To determine the role of C3a-C3a receptor signalling in ischaemia-induced neural plasticity, we subjected C3a receptor-deficient mice, GFAP-C3a transgenic mice expressing biologically active C3a in the central nervous system, and their respective wild-type controls to photothrombotic stroke. We found that C3a overexpression increased, whereas C3a receptor deficiency decreased post-stroke expression of GAP43 (P < 0.01), a marker of axonal sprouting and plasticity, in the peri-infarct cortex. To verify the translational potential of these findings, we used a pharmacological approach. Daily intranasal treatment of wild-type mice with C3a beginning 7 days after stroke induction robustly increased synaptic density (P < 0.01) and expression of GAP43 in peri-infarct cortex (P < 0.05). Importantly, the C3a treatment led to faster and more complete recovery of forepaw motor function (P < 0.05). We conclude that C3a-C3a receptor signalling stimulates post-ischaemic neural plasticity and intranasal treatment with C3a receptor agonists is an attractive approach to improve functional recovery after ischaemic brain injury.
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Affiliation(s)
- Anna Stokowska
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Alison L Atkins
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Javier Morán
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Tulen Pekny
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Linda Bulmer
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Michaela C Pascoe
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Scott R Barnum
- Department of Microbiology, University of Alabama, Birmingham, Alabama, USA
| | - Rick A Wetsel
- Research Center for Immunology and Autoimmune Diseases, Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas-Houston, Houston, Texas, USA
| | - Jonas A Nilsson
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Mike Dragunow
- Department of Pharmacology and Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Marcela Pekna
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden .,Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia.,Hunter Medical Research Institute, University of Newcastle, New South Wales, Australia
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Pekny M, Pekna M, Messing A, Steinhäuser C, Lee JM, Parpura V, Hol EM, Sofroniew MV, Verkhratsky A. Astrocytes: a central element in neurological diseases. Acta Neuropathol 2016; 131:323-45. [PMID: 26671410 DOI: 10.1007/s00401-015-1513-1] [Citation(s) in RCA: 523] [Impact Index Per Article: 65.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 10/28/2015] [Accepted: 11/21/2015] [Indexed: 12/18/2022]
Abstract
The neurone-centred view of the past disregarded or downplayed the role of astroglia as a primary component in the pathogenesis of neurological diseases. As this concept is changing, so is also the perceived role of astrocytes in the healthy and diseased brain and spinal cord. We have started to unravel the different signalling mechanisms that trigger specific molecular, morphological and functional changes in reactive astrocytes that are critical for repairing tissue and maintaining function in CNS pathologies, such as neurotrauma, stroke, or neurodegenerative diseases. An increasing body of evidence shows that the effects of astrogliosis on the neural tissue and its functions are not uniform or stereotypic, but vary in a context-specific manner from astrogliosis being an adaptive beneficial response under some circumstances to a maladaptive and deleterious process in another context. There is a growing support for the concept of astrocytopathies in which the disruption of normal astrocyte functions, astrodegeneration or dysfunctional/maladaptive astrogliosis are the primary cause or the main factor in neurological dysfunction and disease. This review describes the multiple roles of astrocytes in the healthy CNS, discusses the diversity of astroglial responses in neurological disorders and argues that targeting astrocytes may represent an effective therapeutic strategy for Alexander disease, neurotrauma, stroke, epilepsy and Alzheimer's disease as well as other neurodegenerative diseases.
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