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Sheng Y, Hu W, Chen S, Zhu X. Efferocytosis by macrophages in physiological and pathological conditions: regulatory pathways and molecular mechanisms. Front Immunol 2024; 15:1275203. [PMID: 38779685 PMCID: PMC11109379 DOI: 10.3389/fimmu.2024.1275203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 04/17/2024] [Indexed: 05/25/2024] Open
Abstract
Efferocytosis is defined as the highly effective phagocytic removal of apoptotic cells (ACs) by professional or non-professional phagocytes. Tissue-resident professional phagocytes ("efferocytes"), such as macrophages, have high phagocytic capacity and are crucial to resolve inflammation and aid in homeostasis. Recently, numerous exciting discoveries have revealed divergent (and even diametrically opposite) findings regarding metabolic immune reprogramming associated with efferocytosis by macrophages. In this review, we highlight the key metabolites involved in the three phases of efferocytosis and immune reprogramming of macrophages under physiological and pathological conditions. The next decade is expected to yield further breakthroughs in the regulatory pathways and molecular mechanisms connecting immunological outcomes to metabolic cues as well as avenues for "personalized" therapeutic intervention.
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Affiliation(s)
- Yan−Ran Sheng
- Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Wen−Ting Hu
- Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Siman Chen
- Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Xiao−Yong Zhu
- Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
- Key Laboratory of Reproduction Regulation of NPFPC, SIPPR, IRD, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Fudan University, Shanghai, China
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Xie XD, Dong SS, Liu RJ, Shi LL, Zhu T. Mechanism of Efferocytosis in Determining Ischaemic Stroke Resolution-Diving into Microglia/Macrophage Functions and Therapeutic Modality. Mol Neurobiol 2024:10.1007/s12035-024-04060-4. [PMID: 38409642 DOI: 10.1007/s12035-024-04060-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/17/2024] [Indexed: 02/28/2024]
Abstract
After ischaemic cerebral vascular injury, efferocytosis-a process known as the efficient clearance of apoptotic cells (ACs) by various phagocytes in both physiological and pathological states-is crucial for maintaining central nervous system (CNS) homeostasis and regaining prognosis. The mechanisms of efferocytosis in ischaemic stroke and its influence on preventing inflammation progression from secondary injury were still not fully understood, despite the fact that the fundamental process of efferocytosis has been described in a series of phases, including AC recognition, phagocyte engulfment, and subsequent degradation. The genetic reprogramming of macrophages and brain-resident microglia after an ischaemic stroke has been equated by some researchers to that of the peripheral blood and brain. Based on previous studies, some molecules, such as signal transducer and activator of transcription 6 (STAT6), peroxisome proliferator-activated receptor γ (PPARG), CD300A, and sigma non-opioid intracellular receptor 1 (SIGMAR1), were discovered to be largely associated with aspects of apoptotic cell elimination and accompanying neuroinflammation, such as inflammatory cytokine release, phenotype transformation, and suppressing of antigen presentation. Exacerbated stroke outcomes are brought on by defective efferocytosis and improper modulation of pertinent signalling pathways in blood-borne macrophages and brain microglia, which also results in subsequent tissue inflammatory damage. This review focuses on recent researches which contain a number of recently discovered mechanisms, such as studies on the relationship between benign efferocytosis and the regulation of inflammation in ischaemic stroke, the roles of some risk factors in disease progression, and current immune approaches that aim to promote efferocytosis to treat some autoimmune diseases. Understanding these pathways provides insight into novel pathophysiological processes and fresh characteristics, which can be used to build cerebral ischaemia targeting techniques.
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Affiliation(s)
- Xiao-Di Xie
- Department of Pathophysiology, School of Basic Medicine, Institute of Neuroregeneration & Neurorehabilitation, Qingdao University, No. 308 Ningxia Road, Qingdao, China
| | - Shan-Shan Dong
- Department of Pathophysiology, School of Basic Medicine, Institute of Neuroregeneration & Neurorehabilitation, Qingdao University, No. 308 Ningxia Road, Qingdao, China
- Department of Rehabilitation Medicine, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Ru-Juan Liu
- Department of Pathophysiology, School of Basic Medicine, Institute of Neuroregeneration & Neurorehabilitation, Qingdao University, No. 308 Ningxia Road, Qingdao, China
- Department of Rehabilitation Medicine, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Liu-Liu Shi
- Department of Pathophysiology, School of Basic Medicine, Institute of Neuroregeneration & Neurorehabilitation, Qingdao University, No. 308 Ningxia Road, Qingdao, China
- Department of Neurosurgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Ting Zhu
- Department of Pathophysiology, School of Basic Medicine, Institute of Neuroregeneration & Neurorehabilitation, Qingdao University, No. 308 Ningxia Road, Qingdao, China.
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Demirtaş N, Mazlumoğlu BŞ, Palabıyık Yücelik ŞS. Role of NLRP3 Inflammasomes in Neurodegenerative Diseases. Eurasian J Med 2023; 55:98-105. [PMID: 39109852 PMCID: PMC11075041 DOI: 10.5152/eurasianjmed.2023.23349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 12/24/2023] [Indexed: 08/11/2024] Open
Abstract
Large-scale neuronal degeneration in the human brain is a hallmark of neurodegenerative diseases. These diseases range in location and cause, but they all have neurodegenerative characteristics in common. Neurodegenerative diseases, which have almost no efective treatment options, tend to progress irreversibly and cause large socioeconomic and healthcare costs. In recent years, due to the increase in the elderly population, neurodegenerative diseases that have a risk factor with aging are becoming increasingly common. Evidence that neurodegenerative diseases, which have an important place in public health, may be caused by neuroinflammation, has led to comprehensive investigation of neurodegenerative diseases in this regard. Inflammasomes are innate immune system-associated multiproteins that regulate caspase-1 activation and induce inflammation. The NLRP3 inflammasome is the most researched inflammasome and also located in microglia, its activation mediates the maturation and secretion of the inflammatory cytokines interleukin1beta (IL-1β) and IL-18, thus exerting its efects in the central nervous system. Within the scope of this review, experimental and human studies evaluating the role of NLRP3 inflammasome activation and the efects of its inhibition in neurodegenerative diseases frequently encountered in society have been compiled with studies from past to present.
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Affiliation(s)
- Nagihan Demirtaş
- Department of Pharmaceutical Toxicology, Atatürk University Faculty of Pharmacy, Erzurum, Turkey
| | - Büşra Şahin Mazlumoğlu
- Department of Pharmaceutical Toxicology, Atatürk University Faculty of Pharmacy, Erzurum, Turkey
| | - Şaziye Sezin Palabıyık Yücelik
- Department of Pharmaceutical Toxicology, Atatürk University Faculty of Pharmacy, Erzurum, Turkey
- Clinical Research, Development and Design Application and Research Center, Atatürk University, Erzurum, Turkey
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Yamasaki R. Connexins Control Glial Inflammation in Various Neurological Diseases. Int J Mol Sci 2023; 24:16879. [PMID: 38069203 PMCID: PMC10706219 DOI: 10.3390/ijms242316879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 11/25/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Connexins (Cxs) form gap junctions through homotypic/heterotypic oligomerization. Cxs are initially synthesized in the endoplasmic reticulum, then assembled as hexamers in the Golgi apparatus before being integrated into the cell membrane as hemichannels. These hemichannels remain closed until they combine to create gap junctions, directly connecting neighboring cells. Changes in the intracellular or extracellular environment are believed to trigger the opening of hemichannels, creating a passage between the inside and outside of the cell. The size of the channel pore depends on the Cx isoform and cellular context-specific effects such as posttranslational modifications. Hemichannels allow various bioactive molecules, under ~1 kDa, to move in and out of the host cell in the direction of the electrochemical gradient. In this review, we explore the fundamental roles of Cxs and their clinical implications in various neurological dysfunctions, including hereditary diseases, ischemic brain disorders, degenerative conditions, demyelinating disorders, and psychiatric illnesses. The influence of Cxs on the pathomechanisms of different neurological disorders varies depending on the circumstances. Hemichannels are hypothesized to contribute to proinflammatory effects by releasing ATP, adenosine, glutamate, and other bioactive molecules, leading to neuroglial inflammation. Modulating Cxs' hemichannels has emerged as a promising therapeutic approach.
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Affiliation(s)
- Ryo Yamasaki
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
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Van Campenhout R, De Groof TWM, Kadam P, Kwak BR, Muyldermans S, Devoogdt N, Vinken M. Nanobody-based pannexin1 channel inhibitors reduce inflammation in acute liver injury. J Nanobiotechnology 2023; 21:371. [PMID: 37821897 PMCID: PMC10566086 DOI: 10.1186/s12951-023-02137-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 09/29/2023] [Indexed: 10/13/2023] Open
Abstract
BACKGROUND The opening of pannexin1 channels is considered as a key event in inflammation. Pannexin1 channel-mediated release of adenosine triphosphate triggers inflammasome signaling and activation of immune cells. By doing so, pannexin1 channels play an important role in several inflammatory diseases. Although pannexin1 channel inhibition could represent a novel clinical strategy for treatment of inflammatory disorders, therapeutic pannexin1 channel targeting is impeded by the lack of specific, potent and/or in vivo-applicable inhibitors. The goal of this study is to generate nanobody-based inhibitors of pannexin1 channels. RESULTS Pannexin1-targeting nanobodies were developed as potential new pannexin1 channel inhibitors. We identified 3 cross-reactive nanobodies that showed affinity for both murine and human pannexin1 proteins. Flow cytometry experiments revealed binding capacities in the nanomolar range. Moreover, the pannexin1-targeting nanobodies were found to block pannexin1 channel-mediated release of adenosine triphosphate. The pannexin1-targeting nanobodies were also demonstrated to display anti-inflammatory effects in vitro through reduction of interleukin 1 beta amounts. This anti-inflammatory outcome was reproduced in vivo using a human-relevant mouse model of acute liver disease relying on acetaminophen overdosing. More specifically, the pannexin1-targeting nanobodies lowered serum levels of inflammatory cytokines and diminished liver damage. These effects were linked with alteration of the expression of several NLRP3 inflammasome components. CONCLUSIONS This study introduced for the first time specific, potent and in vivo-applicable nanobody-based inhibitors of pannexin1 channels. As demonstrated for the case of liver disease, the pannexin1-targeting nanobodies hold great promise as anti-inflammatory agents, yet this should be further tested for extrahepatic inflammatory disorders. Moreover, the pannexin1-targeting nanobodies represent novel tools for fundamental research regarding the role of pannexin1 channels in pathological and physiological processes.
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Affiliation(s)
- Raf Van Campenhout
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, 1090, Brussels, Belgium
| | - Timo W M De Groof
- In Vivo Cellular and Molecular Imaging Laboratory, Department of Molecular Imaging, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Prashant Kadam
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, 1090, Brussels, Belgium
| | - Brenda R Kwak
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, CH-1211, Geneva, Switzerland
- Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, CH-1211, Geneva, Switzerland
| | - Serge Muyldermans
- Laboratory of Cellular and Molecular Immunology, Bioengineering Sciences Department, Vrije Universiteit Brussel, 1050, Brussels, Belgium
| | - Nick Devoogdt
- In Vivo Cellular and Molecular Imaging Laboratory, Department of Molecular Imaging, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Mathieu Vinken
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, 1090, Brussels, Belgium.
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Role of DAMPs and cell death in autoimmune diseases: the example of multiple sclerosis. Genes Immun 2023; 24:57-70. [PMID: 36750753 DOI: 10.1038/s41435-023-00198-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 01/06/2023] [Accepted: 01/23/2023] [Indexed: 02/09/2023]
Abstract
Multiple sclerosis is a chronic neuroinflammatory demyelinating disease of the central nervous system (CNS) of unknown etiology and still incompletely clarified pathogenesis. The disease is generally considered a disorder resulting from a complex interplay between environmental risk factors and predisposing causal genetic variants. To examine the etiopathogenesis of the disease, two complementary pre-clinical models are currently discussed: the "outside-in" model proposing a peripherally elicited inflammatory/autoimmune attack against degraded myelin as the cause of the disease, and the "inside-out" paradigm implying a primary cytodegenerative process of cells in the CNS that triggers secondary reactive inflammatory/autoimmune responses against myelin debris. In this review, the integrating pathogenetic role of damage-associated molecular patterns (DAMPs) in these two scenario models is examined by focusing on the origin and sources of these molecules, which are known to promote neuroinflammation and, via activation of pattern recognition receptor-bearing antigen-presenting cells, drive and shape autoimmune responses. In particular, environmental factors are discussed that are conceptually defined as agents which produce endogenous DAMPs via induction of regulated cell death (RCD) or act themselves as exogenous DAMPs. Indeed, in the field of autoimmune diseases, including multiple sclerosis, recent research has focused on environmental triggers that cause secondary events in terms of subroutines of RCD, which have been identified as prolific sources of DAMPs. Finally, a model of a DAMP-driven positive feed-forward loop of chronic inflammatory demyelinating processes is proposed, aimed at reconciling the competing "inside-out" and "outside-in" paradigms.
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Obot P, Subah G, Schonwald A, Pan J, Velíšek L, Velíšková J, Stanton PK, Scemes E. Astrocyte and neuronal Panx1 support long-term reference memory in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.16.524236. [PMID: 36711845 PMCID: PMC9882221 DOI: 10.1101/2023.01.16.524236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Pannexin 1 (Panx1) are ubiquitously expressed proteins that form plasma membrane channels permeable to anions and moderate sized signaling molecules (e.g., ATP, glutamate). In the nervous system, activation of Panx1 channels have been extensively shown to contribute to distinct neurological disorders (epilepsy, chronic pain, migraine, neuroAIDS, etc.) but knowledge of extent to which these channels have a physiological role remains restricted to three studies supporting their involvement in hippocampus dependent learning. Given that Panx1 channels may provide an important mechanism for activity-dependent neuron-glia interaction, we used Panx1 transgenic mice with global and cell-type specific deletions of Panx1 to interrogate their participation in working and reference memory. Using the 8-arm radial maze, we show that long-term spatial reference memory, but not spatial working memory, is deficient in Panx1-null mice and that both astrocyte and neuronal Panx1 contribute to the consolidation of long-term spatial memory. Field potential recordings in hippocampal slices of Panx1-null mice revealed an attenuation of both long-term potentiation (LTP) of synaptic strength and long-term depression (LTD) at Schaffer collateral - CA1 synapses without alterations basal synaptic transmission or pre-synaptic paired-pulse facilitation. Our results implicate both neuronal and astrocyte Panx1 channels as critical players for the development and maintenance of long-term spatial reference memory in mice.
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Obot P, Subah G, Schonwald A, Pan J, Velíšek L, Velíšková J, Stanton PK, Scemes E. Astrocyte and Neuronal Panx1 Support Long-Term Reference Memory in Mice. ASN Neuro 2023; 15:17590914231184712. [PMID: 37365910 DOI: 10.1177/17590914231184712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023] Open
Abstract
Pannexin 1 (Panx1) is an ubiquitously expressed protein that forms plasma membrane channels permeable to anions and moderate-sized signaling molecules (e.g., ATP, glutamate). In the nervous system, activation of Panx1 channels has been extensively shown to contribute to distinct neurological disorders (epilepsy, chronic pain, migraine, neuroAIDS, etc.), but knowledge of the extent to which these channels have a physiological role remains restricted to three studies supporting their involvement in hippocampus dependent learning. Given that Panx1 channels may provide an important mechanism for activity-dependent neuron-glia interaction, we used Panx1 transgenic mice with global and cell-type specific deletions of Panx1 to interrogate their participation in working and reference memory. Using the eight-arm radial maze, we show that long-term spatial reference memory, but not spatial working memory, is deficient in Panx1-null mice and that both astrocyte and neuronal Panx1 contribute to the consolidation of long-term spatial memory. Field potential recordings in hippocampal slices of Panx1-null mice revealed an attenuation of both long-term potentiation (LTP) of synaptic strength and long-term depression (LTD) at Schaffer collateral-CA1 synapses without alterations of basal synaptic transmission or pre-synaptic paired-pulse facilitation. Our results implicate both neuronal and astrocyte Panx1 channels as critical players for the development and maintenance of long-term spatial reference memory in mice.
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Affiliation(s)
- Price Obot
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
- Department of Emergency Medicine, Penn State Hershey Medical Center, Hershey, PA, USA
| | - Galadu Subah
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
| | - Antonia Schonwald
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
| | - Jian Pan
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
| | - Libor Velíšek
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
- Department of Pediatrics, Penn State Hershey Medical Center, Hershey, PA, USA
- Department of Neurology, New York Medical College, Valhalla, NY, USA
| | - Jana Velíšková
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
- Department of Obstetrics and Gynecology, New York Medical College, Valhalla, NY, USA
| | - Patric K Stanton
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
- Department of Neurology, New York Medical College, Valhalla, NY, USA
| | - Eliana Scemes
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
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Alnafisah R, Lundh A, Asah SM, Hoeflinger J, Wolfinger A, Hamoud AR, McCullumsmith RE, O'Donovan SM. Altered purinergic receptor expression in the frontal cortex in schizophrenia. SCHIZOPHRENIA (HEIDELBERG, GERMANY) 2022; 8:96. [PMID: 36376358 PMCID: PMC9663420 DOI: 10.1038/s41537-022-00312-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/03/2022] [Indexed: 04/27/2023]
Abstract
ATP functions as a neurotransmitter, acting on the ubiquitously expressed family of purinergic P2 receptors. In schizophrenia (SCZ), the pathways that modulate extracellular ATP and its catabolism to adenosine are dysregulated. However, the effects of altered ATP availability on P2 receptor expression in the brain in SCZ have not been assessed. We assayed P2 receptor mRNA and protein expression in the DLPFC and ACC in subjects diagnosed with SCZ and matched, non-psychiatrically ill controls (n = 20-22/group). P2RX7, P2RX4 and male P2RX5 mRNA expression were significantly increased (p < 0.05) in the DLPFC in SCZ. Expression of P2RX7 protein isoform was also significantly increased (p < 0.05) in the DLPFC in SCZ. Significant increases in P2RX4 and male P2RX5 mRNA expression may be associated with antipsychotic medication effects. We found that P2RX4 and P2RX7 mRNA are significantly correlated with the inflammatory marker SERPINA3, and may suggest an association between upregulated P2XR and neuroinflammation in SCZ. These findings lend support for brain-region dependent dysregulation of the purinergic system in SCZ.
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Affiliation(s)
- Rawan Alnafisah
- Department of Neurosciences, University of Toledo, Toledo, OH, USA
| | - Anna Lundh
- Department of Neurosciences, University of Toledo, Toledo, OH, USA
| | - Sophie M Asah
- Department of Neurosciences, University of Toledo, Toledo, OH, USA
| | - Julie Hoeflinger
- Department of Neurosciences, University of Toledo, Toledo, OH, USA
| | - Alyssa Wolfinger
- Department of Neurosciences, University of Toledo, Toledo, OH, USA
| | | | - Robert E McCullumsmith
- Department of Neurosciences, University of Toledo, Toledo, OH, USA
- Neurosciences Institute, Promedica, Toledo, OH, USA
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Cai X, Li H, Wang M, Chu E, Wei N, Lin J, Hu Y, Dai J, Chen A, Zheng H, Zhang Q, Zhong Y, Chang R, Wu S, Xiao Y, Liu C. mTOR Participates in the Formation, Maintenance, and Function of Memory CD8 +T Cells Regulated by Glycometabolism. Biochem Pharmacol 2022; 204:115197. [PMID: 35926651 DOI: 10.1016/j.bcp.2022.115197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/21/2022] [Accepted: 07/27/2022] [Indexed: 11/02/2022]
Abstract
Memory CD8+T cells participate in the fight against infection and tumorigenesis as well as in autoimmune disease progression because of their efficient and rapid immune response, long-term survival, and continuous differentiation. At each stage of their formation, maintenance, and function, the cell metabolism must be adjusted to match the functional requirements of the specific stage. Notably, enhanced glycolytic metabolism can generate sufficient levels of adenosine triphosphate (ATP) to form memory CD8+T cells, countering the view that glycolysis prevents the formation of memory CD8+T cells. This review focuses on how glycometabolism regulates memory CD8+T cells and highlights the key mechanisms through which the mammalian target of rapamycin (mTOR) signaling pathway affects memory CD8+T cell formation, maintenance, and function by regulating glycometabolism. In addition, different subpopulations of memory CD8+T cells exhibit different metabolic flexibility during their formation, survival, and functional stages, during which the energy metabolism may be critical. These findings which may explain why enhanced glycolytic metabolism can give rise to memory CD8+T cells. Modulating the metabolism of memory CD8+T cells to influence specific cell fates may be useful for disease treatment.
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Affiliation(s)
- Xuepei Cai
- Department of Orthodontics, Stomatological Hospital, Southern Medical University, Guangzhou, China
| | - Haokun Li
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Manyi Wang
- Department of Orthodontics, Stomatological Hospital, Southern Medical University, Guangzhou, China
| | - Edward Chu
- Department of Oncology and Cancer Therapeutics Program, Albert Einstein Cancer Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Ning Wei
- Department of Oncology and Cancer Therapeutics Program, Albert Einstein Cancer Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Jiayu Lin
- Department of Orthodontics, Stomatological Hospital, Southern Medical University, Guangzhou, China
| | - Yun Hu
- Department of Orthodontics, Stomatological Hospital, Southern Medical University, Guangzhou, China
| | - Jingtao Dai
- Department of Orthodontics, Stomatological Hospital, Southern Medical University, Guangzhou, China
| | - Aijie Chen
- Stomatological Hospital, Southern Medical University, Guangzhou, China
| | - Hua Zheng
- Department of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qianbing Zhang
- Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Yuxia Zhong
- Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Ruoshui Chang
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Sha Wu
- Department of Immunology, School of Basic Medical Sciences, Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Functional Proteomics of Guangdong Province, Guangzhou, China; National Demonstration Center for Experimental Education of Basic Medical Sciences of China, Guangzhou, China.
| | - Yaomu Xiao
- Department of Orthodontics, Stomatological Hospital, Southern Medical University, Guangzhou, China.
| | - Chufeng Liu
- Department of Orthodontics, Stomatological Hospital, Southern Medical University, Guangzhou, China.
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11
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Nobili P, Shen W, Milicevic K, Bogdanovic Pristov J, Audinat E, Nikolic L. Therapeutic Potential of Astrocyte Purinergic Signalling in Epilepsy and Multiple Sclerosis. Front Pharmacol 2022; 13:900337. [PMID: 35586058 PMCID: PMC9109958 DOI: 10.3389/fphar.2022.900337] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Epilepsy and multiple sclerosis (MS), two of the most common neurological diseases, are characterized by the establishment of inflammatory environment in the central nervous system that drives disease progression and impacts on neurodegeneration. Current therapeutic approaches in the treatments of epilepsy and MS are targeting neuronal activity and immune cell response, respectively. However, the lack of fully efficient responses to the available treatments obviously shows the need to search for novel therapeutic candidates that will not exclusively target neurons or immune cells. Accumulating knowledge on epilepsy and MS in humans and analysis of relevant animal models, reveals that astrocytes are promising therapeutic candidates to target as they participate in the modulation of the neuroinflammatory response in both diseases from the initial stages and may play an important role in their development. Indeed, astrocytes respond to reactive immune cells and contribute to the neuronal hyperactivity in the inflamed brain. Mechanistically, these astrocytic cell to cell interactions are fundamentally mediated by the purinergic signalling and involve metabotropic P2Y1 receptors in case of astrocyte interactions with neurons, while ionotropic P2X7 receptors are mainly involved in astrocyte interactions with autoreactive immune cells. Herein, we review the potential of targeting astrocytic purinergic signalling mediated by P2Y1 and P2X7 receptors to develop novel approaches for treatments of epilepsy and MS at very early stages.
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Affiliation(s)
- Paola Nobili
- Institute of Functional Genomics (IGF), University of Montpellier, CNRS, INSERM, Montpellier, France
| | - Weida Shen
- School of Medicine, Zhejiang University City College, Hangzhou, China
| | - Katarina Milicevic
- Center for Laser Microscopy, Institute of Physiology and Biochemistry “Ivan Djaja”, University of Belgrade, Faculty of Biology, Belgrade, Serbia
| | - Jelena Bogdanovic Pristov
- Department of Life Sciences, University of Belgrade, Institute for Multidisciplinary Research, Belgrade, Serbia
| | - Etienne Audinat
- Institute of Functional Genomics (IGF), University of Montpellier, CNRS, INSERM, Montpellier, France
| | - Ljiljana Nikolic
- Department of Neurophysiology, University of Belgrade, Institute for Biological Research Siniša Stanković, National Institute of Republic of Serbia, Belgrade, Serbia
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12
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Zhao J, Zhang W, Wu T, Wang H, Mao J, Liu J, Zhou Z, Lin X, Yan H, Wang Q. Efferocytosis in the Central Nervous System. Front Cell Dev Biol 2021; 9:773344. [PMID: 34926460 PMCID: PMC8678611 DOI: 10.3389/fcell.2021.773344] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 10/25/2021] [Indexed: 11/23/2022] Open
Abstract
The effective clearance of apoptotic cells is essential for maintaining central nervous system (CNS) homeostasis and restoring homeostasis after injury. In most cases of physiological apoptotic cell death, efferocytosis prevents inflammation and other pathological conditions. When apoptotic cells are not effectively cleared, destruction of the integrity of the apoptotic cell membrane integrity, leakage of intracellular contents, and secondary necrosis may occur. Efferocytosis is the mechanism by which efferocytes quickly remove apoptotic cells from tissues before they undergo secondary necrosis. Cells with efferocytosis functions, mainly microglia, help to eliminate apoptotic cells from the CNS. Here, we discuss the impacts of efferocytosis on homeostasis, the mechanism of efferocytosis, the associations of efferocytosis failure and CNS diseases, and the current clinical applications of efferocytosis. We also identify efferocytosis as a novel potential target for exploring the causes and treatments of CNS diseases.
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Affiliation(s)
- Jiayi Zhao
- Department of Anesthesia, Zhejiang Hospital, Hangzhou, China
| | - Weiqi Zhang
- The First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Tingting Wu
- The First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Hongyi Wang
- The First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Jialiang Mao
- The First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Jian Liu
- The First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Ziheng Zhou
- The First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Xianfeng Lin
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Huige Yan
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Qingqing Wang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
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13
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Koval M, Cwiek A, Carr T, Good ME, Lohman AW, Isakson BE. Pannexin 1 as a driver of inflammation and ischemia-reperfusion injury. Purinergic Signal 2021; 17:521-531. [PMID: 34251590 PMCID: PMC8273370 DOI: 10.1007/s11302-021-09804-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 06/24/2021] [Indexed: 02/06/2023] Open
Abstract
Pannexin 1 (Panx1) is a ubiquitously expressed protein forming large conductance channels that are central to many distinct inflammation and injury responses. There is accumulating evidence showing ATP released from Panx1 channels, as well as metabolites, provide effective paracrine and autocrine signaling molecules that regulate different elements of the injury response. As channels with a broad range of permselectivity, Panx1 channels mediate the secretion and uptake of multiple solutes, ranging from calcium to bacterial derived molecules. In this review, we describe how Panx1 functions in response to different pro-inflammatory stimuli, focusing mainly on signaling coordinated by the vasculature. How Panx1 mediates ATP release by injured cells is also discussed. The ability of Panx1 to serve as a central component of many diverse physiologic responses has proven to be critically dependent on the context of expression, post-translational modification, interacting partners, and the mode of stimulation.
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Affiliation(s)
- Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, 205 Whitehead Building, 615 Michael Street, Atlanta, GA, 30322, USA.
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Aleksandra Cwiek
- Department of Cell Biology, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - Thomas Carr
- Department of Cell Biology and Anatomy, University of Calgary Cumming School of Medicine, Calgary, AB, Canada
- Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Miranda E Good
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA, USA
| | - Alexander W Lohman
- Department of Cell Biology and Anatomy, University of Calgary Cumming School of Medicine, Calgary, AB, Canada
- Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, School of Medicine, University of Virginia, PO Box 801394, Charlottesville, VA, 22908, USA.
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA.
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14
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Boscia F, Elkjaer ML, Illes Z, Kukley M. Altered Expression of Ion Channels in White Matter Lesions of Progressive Multiple Sclerosis: What Do We Know About Their Function? Front Cell Neurosci 2021; 15:685703. [PMID: 34276310 PMCID: PMC8282214 DOI: 10.3389/fncel.2021.685703] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 05/23/2021] [Indexed: 12/19/2022] Open
Abstract
Despite significant advances in our understanding of the pathophysiology of multiple sclerosis (MS), knowledge about contribution of individual ion channels to axonal impairment and remyelination failure in progressive MS remains incomplete. Ion channel families play a fundamental role in maintaining white matter (WM) integrity and in regulating WM activities in axons, interstitial neurons, glia, and vascular cells. Recently, transcriptomic studies have considerably increased insight into the gene expression changes that occur in diverse WM lesions and the gene expression fingerprint of specific WM cells associated with secondary progressive MS. Here, we review the ion channel genes encoding K+, Ca2+, Na+, and Cl- channels; ryanodine receptors; TRP channels; and others that are significantly and uniquely dysregulated in active, chronic active, inactive, remyelinating WM lesions, and normal-appearing WM of secondary progressive MS brain, based on recently published bulk and single-nuclei RNA-sequencing datasets. We discuss the current state of knowledge about the corresponding ion channels and their implication in the MS brain or in experimental models of MS. This comprehensive review suggests that the intense upregulation of voltage-gated Na+ channel genes in WM lesions with ongoing tissue damage may reflect the imbalance of Na+ homeostasis that is observed in progressive MS brain, while the upregulation of a large number of voltage-gated K+ channel genes may be linked to a protective response to limit neuronal excitability. In addition, the altered chloride homeostasis, revealed by the significant downregulation of voltage-gated Cl- channels in MS lesions, may contribute to an altered inhibitory neurotransmission and increased excitability.
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Affiliation(s)
- Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", Naples, Italy
| | - Maria Louise Elkjaer
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Zsolt Illes
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Neurology, Odense University Hospital, Odense, Denmark
| | - Maria Kukley
- Achucarro Basque Center for Neuroscience, Leioa, Spain.,Ikerbasque Basque Foundation for Science, Bilbao, Spain
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15
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Seo JH, Dalal MS, Contreras JE. Pannexin-1 Channels as Mediators of Neuroinflammation. Int J Mol Sci 2021; 22:ijms22105189. [PMID: 34068881 PMCID: PMC8156193 DOI: 10.3390/ijms22105189] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/04/2021] [Accepted: 05/06/2021] [Indexed: 02/06/2023] Open
Abstract
Neuroinflammation is a major component of central nervous system (CNS) injuries and neurological diseases, including Alzheimer’s disease, multiple sclerosis, neuropathic pain, and brain trauma. The activation of innate immune cells at the damage site causes the release of pro-inflammatory cytokines and chemokines, which alter the functionality of nearby tissues and might mediate the recruitment of leukocytes to the injury site. If this process persists or is exacerbated, it prevents the adequate resolution of the inflammation, and ultimately enhances secondary damage. Adenosine 5′ triphosphate (ATP) is among the molecules released that trigger an inflammatory response, and it serves as a chemotactic and endogenous danger signal. Extracellular ATP activates multiple purinergic receptors (P2X and P2Y) that have been shown to promote neuroinflammation in a variety of CNS diseases. Recent studies have shown that Pannexin-1 (Panx1) channels are the principal conduits of ATP release from dying cells and innate immune cells in the brain. Herein, we review the emerging evidence that directly implicates Panx-1 channels in the neuroinflammatory response in the CNS.
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Affiliation(s)
- Joon Ho Seo
- Department of Neurology and Nash Family, Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine, Mount Sinai, New York, NY 10029, USA;
| | - Miloni S. Dalal
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, Newark, NJ 07103, USA;
| | - Jorge E. Contreras
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, Newark, NJ 07103, USA;
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA 95616, USA
- Correspondence: ; Tel.: +1-530-754-2770
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16
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Paracellular and Transcellular Leukocytes Diapedesis Are Divergent but Interconnected Evolutionary Events. Genes (Basel) 2021; 12:genes12020254. [PMID: 33578809 PMCID: PMC7916592 DOI: 10.3390/genes12020254] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 02/03/2021] [Accepted: 02/06/2021] [Indexed: 12/15/2022] Open
Abstract
Infiltration of the endothelial layer of the blood-brain barrier by leukocytes plays a critical role in health and disease. When passing through the endothelial layer during the diapedesis process lymphocytes can either follow a paracellular route or a transcellular one. There is a debate whether these two processes constitute one mechanism, or they form two evolutionary distinct migration pathways. We used artificial intelligence, phylogenetic analysis, HH search, ancestor sequence reconstruction to investigate further this intriguing question. We found that the two systems share several ancient components, such as RhoA protein that plays a critical role in controlling actin movement in both mechanisms. However, some of the key components differ between these two transmigration processes. CAV1 genes emerged during Trichoplax adhaerens, and it was only reported in transcellular process. Paracellular process is dependent on PECAM1. PECAM1 emerged from FASL5 during Zebrafish divergence. Lastly, both systems employ late divergent genes such as ICAM1 and VECAM1. Taken together, our results suggest that these two systems constitute two different mechanical sensing mechanisms of immune cell infiltrations of the brain, yet these two systems are connected. We postulate that the mechanical properties of the cellular polarity is the main driving force determining the migration pathway. Our analysis indicates that both systems coevolved with immune cells, evolving to a higher level of complexity in association with the evolution of the immune system.
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17
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P2X7 Receptors Amplify CNS Damage in Neurodegenerative Diseases. Int J Mol Sci 2020; 21:ijms21175996. [PMID: 32825423 PMCID: PMC7504621 DOI: 10.3390/ijms21175996] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/07/2020] [Accepted: 08/17/2020] [Indexed: 12/11/2022] Open
Abstract
ATP is a (co)transmitter and signaling molecule in the CNS. It acts at a multitude of ligand-gated cationic channels termed P2X to induce rapid depolarization of the cell membrane. Within this receptor-channel family, the P2X7 receptor (R) allows the transmembrane fluxes of Na+, Ca2+, and K+, but also allows the slow permeation of larger organic molecules. This is supposed to cause necrosis by excessive Ca2+ influx, as well as depletion of intracellular ions and metabolites. Cell death may also occur by apoptosis due to the activation of the caspase enzymatic cascade. Because P2X7Rs are localized in the CNS preferentially on microglia, but also at a lower density on neuroglia (astrocytes, oligodendrocytes) the stimulation of this receptor leads to the release of neurodegeneration-inducing bioactive molecules such as pro-inflammatory cytokines, chemokines, proteases, reactive oxygen and nitrogen molecules, and the excitotoxic glutamate/ATP. Various neurodegenerative reactions of the brain/spinal cord following acute harmful events (mechanical CNS damage, ischemia, status epilepticus) or chronic neurodegenerative diseases (neuropathic pain, Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, amyotrophic lateral sclerosis) lead to a massive release of ATP via the leaky plasma membrane of neural tissue. This causes cellular damage superimposed on the original consequences of neurodegeneration. Hence, blood-brain-barrier permeable pharmacological antagonists of P2X7Rs with excellent bioavailability are possible therapeutic agents for these diseases. The aim of this review article is to summarize our present state of knowledge on the involvement of P2X7R-mediated events in neurodegenerative illnesses endangering especially the life quality and duration of the aged human population.
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18
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Andrejew R, Oliveira-Giacomelli Á, Ribeiro DE, Glaser T, Arnaud-Sampaio VF, Lameu C, Ulrich H. The P2X7 Receptor: Central Hub of Brain Diseases. Front Mol Neurosci 2020; 13:124. [PMID: 32848594 PMCID: PMC7413029 DOI: 10.3389/fnmol.2020.00124] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/17/2020] [Indexed: 12/27/2022] Open
Abstract
The P2X7 receptor is a cation channel activated by high concentrations of adenosine triphosphate (ATP). Upon long-term activation, it complexes with membrane proteins forming a wide pore that leads to cell death and increased release of ATP into the extracellular milieu. The P2X7 receptor is widely expressed in the CNS, such as frontal cortex, hippocampus, amygdala and striatum, regions involved in neurodegenerative diseases and psychiatric disorders. Despite P2X7 receptor functions in glial cells have been extensively studied, the existence and roles of this receptor in neurons are still controversially discussed. Regardless, P2X7 receptors mediate several processes observed in neuropsychiatric disorders and brain tumors, such as activation of neuroinflammatory response, stimulation of glutamate release and neuroplasticity impairment. Moreover, P2X7 receptor gene polymorphisms have been associated to depression, and isoforms of P2X7 receptors are implicated in neuropsychiatric diseases. In view of that, the P2X7 receptor has been proposed to be a potential target for therapeutic intervention in brain diseases. This review discusses the molecular mechanisms underlying P2X7 receptor-mediated signaling in neurodegenerative diseases, psychiatric disorders, and brain tumors. In addition, it highlights the recent advances in the development of P2X7 receptor antagonists that are able of penetrating the central nervous system.
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Affiliation(s)
- Roberta Andrejew
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | - Deidiane Elisa Ribeiro
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Talita Glaser
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | - Claudiana Lameu
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Henning Ulrich
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
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19
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Papaneophytou C, Georgiou E, Kleopa KA. The role of oligodendrocyte gap junctions in neuroinflammation. Channels (Austin) 2020; 13:247-263. [PMID: 31232168 PMCID: PMC6602578 DOI: 10.1080/19336950.2019.1631107] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Gap junctions (GJs) provide channels for direct cell-to-cell connectivity serving the homeostasis in several organs of vertebrates including the central (CNS) and peripheral (PNS) nervous systems. GJs are composed of connexins (Cx), which show a highly distinct cellular and subcellular expression pattern. Oligodendrocytes, the myelinating cells of the CNS, are characterized by extensive GJ connectivity with each other as well as with astrocytes. The main oligodendrocyte connexins forming these GJ channels are Cx47 and Cx32. The importance of these channels has been highlighted by the discovery of human diseases caused by mutations in oligodendrocyte connexins, manifesting with leukodystrophy or transient encephalopathy. Experimental models have provided further evidence that oligodendrocyte GJs are essential for CNS myelination and homeostasis, while a strong inflammatory component has been recognized in the absence of oligodendrocyte connexins. Further studies revealed that connexins are also disrupted in multiple sclerosis (MS) brain, and in experimental models of induced inflammatory demyelination. Moreover, induced demyelination was more severe and associated with higher degree of CNS inflammation in models with oligodendrocyte GJ deficiency, suggesting that disrupted connexin expression in oligodendrocytes is not only a consequence but can also drive a pro-inflammatory environment in acquired demyelinating disorders such as MS. In this review, we summarize the current insights from human disorders as well as from genetic and acquired models of demyelination related to oligodendrocyte connexins, with the remaining challenges and perspectives.
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Affiliation(s)
- Christos Papaneophytou
- a Neuroscience Laboratory, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine , Nicosia , Cyprus.,b Department of Life and Health Sciences, School of Sciences and Engineering , University of Nicosia , Nicosia , Cyprus
| | - Elena Georgiou
- a Neuroscience Laboratory, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine , Nicosia , Cyprus
| | - Kleopas A Kleopa
- a Neuroscience Laboratory, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine , Nicosia , Cyprus.,c Neurology Clinics , the Cyprus Institute of Neurology and Genetics, and the Cyprus School of Molecular Medicine , Nicosia , Cyprus
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20
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Yavarpour-Bali H, Ghasemi-Kasman M. The role of inflammasomes in multiple sclerosis. Mult Scler 2020; 27:1323-1331. [PMID: 32539629 DOI: 10.1177/1352458520932776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Multiple sclerosis (MS) is considered as an inflammatory autoimmune disease of the central nervous system (CNS), with a complex and heterogenic etiology. However, the involvement of inflammation in its pathophysiology is well documented and current therapies for MS are mainly immunosuppressive drugs. Although the available drugs reduce new lesions and relapses, their long-term outcome is not completely satisfactory. Inflammasomes are multimeric protein complexes that play a critical role in the inflammatory process. Several lines of evidence suggest an association between inflammasome activation and MS. In this paper, we have reviewed current studies that demonstrate the involvement of inflammasomes in MS development, in both animal model and MS patients. Furthermore, prior studies about the effect of inflammasome inhibitor drugs on development and progression of MS are discussed.
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Affiliation(s)
| | - Maryam Ghasemi-Kasman
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran/Neuroscience Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
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21
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Yeung AK, Patil CS, Jackson MF. Pannexin‐1 in the CNS: Emerging concepts in health and disease. J Neurochem 2020; 154:468-485. [DOI: 10.1111/jnc.15004] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/26/2020] [Accepted: 03/09/2020] [Indexed: 12/15/2022]
Affiliation(s)
- Albert K. Yeung
- Department of Pharmacology and Therapeutics Max Rady College of Medicine Rady Faculty of Health Sciences University of Manitoba Winnipeg Manitoba Canada
- Neuroscience Research Program Kleysen Institute for Advanced Medicine University of Manitoba Winnipeg Manitoba Canada
| | - Chetan S. Patil
- Department of Pharmacology and Therapeutics Max Rady College of Medicine Rady Faculty of Health Sciences University of Manitoba Winnipeg Manitoba Canada
- Neuroscience Research Program Kleysen Institute for Advanced Medicine University of Manitoba Winnipeg Manitoba Canada
| | - Michael F. Jackson
- Department of Pharmacology and Therapeutics Max Rady College of Medicine Rady Faculty of Health Sciences University of Manitoba Winnipeg Manitoba Canada
- Neuroscience Research Program Kleysen Institute for Advanced Medicine University of Manitoba Winnipeg Manitoba Canada
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22
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Boada-Romero E, Martinez J, Heckmann BL, Green DR. The clearance of dead cells by efferocytosis. Nat Rev Mol Cell Biol 2020; 21:398-414. [PMID: 32251387 DOI: 10.1038/s41580-020-0232-1] [Citation(s) in RCA: 380] [Impact Index Per Article: 95.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2020] [Indexed: 02/06/2023]
Abstract
Multiple modes of cell death have been identified, each with a unique function and each induced in a setting-dependent manner. As billions of cells die during mammalian embryogenesis and daily in adult organisms, clearing dead cells and associated cellular debris is important in physiology. In this Review, we present an overview of the phagocytosis of dead and dying cells, a process known as efferocytosis. Efferocytosis is performed by macrophages and to a lesser extent by other 'professional' phagocytes (such as monocytes and dendritic cells) and 'non-professional' phagocytes, such as epithelial cells. Recent discoveries have shed light on this process and how it functions to maintain tissue homeostasis, tissue repair and organismal health. Here, we outline the mechanisms of efferocytosis, from the recognition of dying cells through to phagocytic engulfment and homeostatic resolution, and highlight the pathophysiological consequences that can arise when this process is abrogated.
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Affiliation(s)
- Emilio Boada-Romero
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Jennifer Martinez
- Inflammation & Autoimmunity Group, National Institute for Environmental Health Sciences, Research Triangle Park, Durham, NC, USA
| | - Bradlee L Heckmann
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA.
| | - Douglas R Green
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA.
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23
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Surface Grafted MSI-78A Antimicrobial Peptide has High Potential for Gastric Infection Management. Sci Rep 2019; 9:18212. [PMID: 31796755 PMCID: PMC6890677 DOI: 10.1038/s41598-019-53918-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 10/14/2019] [Indexed: 12/20/2022] Open
Abstract
As we approach the end of the antibiotic era, newer therapeutic options, such as antimicrobial peptides (AMPs), are in urgent demand. AMP surface grafting onto biomaterials has been described as a good strategy to overcome problems associated with their in vivo stability. Helicobacter pylori is among the bacteria that pose greatest threat to human health, being MSI-78A one of the few bactericidal AMPs against this bacterium. Here, we report that MSI-78A grafted onto model surfaces (Self-Assembled Monolayers –SAMs), in a concentration of 30.3 ± 1.2 ng/cm2 determined by quartz crystal microbalance with dissipation (QCM-D), was able to kill, by contact, 98% of planktonic H. pylori in only 2 h. This fact was not verified against the control bacteria (Staphylococcus epidermidis), although the minimal inhibitory concentration (MIC) of MSI-78A in solution is much lower for S. epidermidis (2 μg/mL) than for H. pylori (64 μg/mL). Our results also demonstrated that, in opposite to other bacteria, H. pylori cells were attracted to ethylene glycol terminated (antiadhesive) surfaces, which can explain the high bactericidal potential of grafted MSI-78A. This proof of concept study establishes the foundations for development of MSI-78A grafted nanoparticles for gastric infection management within a targeted nanomedicine concept.
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24
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Brocardo L, Acosta LE, Piantanida AP, Rela L. Beneficial and Detrimental Remodeling of Glial Connexin and Pannexin Functions in Rodent Models of Nervous System Diseases. Front Cell Neurosci 2019; 13:491. [PMID: 31780897 PMCID: PMC6851021 DOI: 10.3389/fncel.2019.00491] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/17/2019] [Indexed: 01/30/2023] Open
Abstract
A variety of glial cell functions are supported by connexin and pannexin proteins. These functions include the modulation of synaptic gain, the control of excitability through regulation of the ion and neurotransmitter composition of the extracellular milieu and the promotion of neuronal survival. Connexins and pannexins support these functions through diverse molecular mechanisms, including channel and non-channel functions. The former comprise the formation of gap junction-mediated networks supported by connexin intercellular channels and the formation of pore-like membrane structures or hemichannels formed by both connexins and pannexins. Non-channel functions involve adhesion properties and the participation in signaling intracellular cascades. Pathological conditions of the nervous system such as ischemia, neurodegeneration, pathogen infection, trauma and tumors are characterized by distinctive remodeling of connexin expression and function. However, whether these changes can be interpreted as part of the pathogenesis, or as beneficial compensatory effects, remains under debate. Here we review the available evidence addressing this matter with a special emphasis in mouse models with selective manipulation of glial connexin and pannexin proteins in vivo. We postulate that the beneficial vs. detrimental effects of glial connexin remodeling in pathological conditions depend on the impact of remodeling on the different connexin and pannexin channel and non-channel functions, on the characteristics of the inflammatory environment and on the type of interaction among glial cells types.
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Affiliation(s)
- Lucila Brocardo
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Luis Ernesto Acosta
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ana Paula Piantanida
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Lorena Rela
- Grupo de Neurociencia de Sistemas, Facultad de Medicina, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
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25
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Gheibi Hayat SM, Bianconi V, Pirro M, Sahebkar A. Efferocytosis: molecular mechanisms and pathophysiological perspectives. Immunol Cell Biol 2018; 97:124-133. [DOI: 10.1111/imcb.12206] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 09/15/2018] [Accepted: 09/16/2018] [Indexed: 12/28/2022]
Affiliation(s)
| | - Vanessa Bianconi
- Unit of Internal Medicine, Angiology and Arteriosclerosis Diseases; Department of Medicine; University of Perugia; Perugia Italy
| | - Matteo Pirro
- Unit of Internal Medicine, Angiology and Arteriosclerosis Diseases; Department of Medicine; University of Perugia; Perugia Italy
| | - Amirhossein Sahebkar
- Biotechnology Research Center; Pharmaceutical Technology Institute; Mashhad University of Medical Sciences; Mashhad Iran
- Neurogenic Inflammation Research Center; Mashhad University of Medical Sciences; Mashhad Iran
- School of Pharmacy; Mashhad University of Medical Sciences; Mashhad Iran
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26
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Pacheco-Costa R, Davis HM, Atkinson EG, Dilley JE, Byiringiro I, Aref MW, Allen MR, Bellido T, Plotkin LI. Reversal of loss of bone mass in old mice treated with mefloquine. Bone 2018; 114:22-31. [PMID: 29879544 PMCID: PMC6056320 DOI: 10.1016/j.bone.2018.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/16/2018] [Accepted: 06/04/2018] [Indexed: 11/16/2022]
Abstract
Aging is accompanied by imbalanced bone remodeling, elevated osteocyte apoptosis, and decreased bone mass and mechanical properties; and improved pharmacologic approaches to counteract bone deterioration with aging are needed. We examined herein the effect of mefloquine, a drug used to treat malaria and systemic lupus erythematosus and shown to ameliorate bone loss in glucocorticoid-treated patients, on bone mass and mechanical properties in young and old mice. Young 3.5-month-old and old 21-month-old female C57BL/6 mice received daily injections of 5 mg/kg/day mefloquine for 14 days. Aging resulted in the expected changes in bone volume and mechanical properties. In old mice mefloquine administration reversed the lower vertebral cancellous bone volume and bone formation; and had modest effects on cortical bone volume, thickness, and moment of inertia. Mefloquine administration did not change the levels of the circulating bone formation markers P1NP or alkaline phosphatase, whereas levels of the resorption marker CTX showed trends towards increase with mefloquine treatment. In addition, and as expected, aging bones exhibited an accumulation of active caspase3-expressing osteocytes and higher expression of apoptosis-related genes compared to young mice, which were not altered by mefloquine administration at either age. In young animals, mefloquine induced higher periosteal bone formation, but lower endocortical bone formation. Further, osteoclast numbers were higher on the endocortical bone surface and circulating CTX levels were increased, in mefloquine- compared to vehicle-treated young mice. Consistent with this, addition of mefloquine to bone marrow cells isolated from young mice led to increased osteoclastic gene expression and a tendency towards increased osteoclast numbers in vitro. Taken together our findings identify the age and bone-site specific skeletal effects of mefloquine. Further, our results highlight a beneficial effect of mefloquine administration on vertebral cancellous bone mass in old animals, raising the possibility of using this pharmacologic inhibitor to preserve skeletal health with aging.
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Affiliation(s)
- Rafael Pacheco-Costa
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Hannah M Davis
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Emily G Atkinson
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Julian E Dilley
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Innocent Byiringiro
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Mohammad W Aref
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Matthew R Allen
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Roudebush Veterans Administration Medical Center, Indianapolis, IN 46202, USA.
| | - Teresita Bellido
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Roudebush Veterans Administration Medical Center, Indianapolis, IN 46202, USA; Division of Endocrinology, Department of Internal Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Lilian I Plotkin
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Roudebush Veterans Administration Medical Center, Indianapolis, IN 46202, USA.
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Seref-Ferlengez Z, Urban-Maldonado M, Sun HB, Schaffler MB, Suadicani SO, Thi MM. Role of pannexin 1 channels in load-induced skeletal response. Ann N Y Acad Sci 2018; 1442:79-90. [PMID: 29952014 DOI: 10.1111/nyas.13914] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 05/18/2018] [Accepted: 06/01/2018] [Indexed: 12/31/2022]
Abstract
The pannexin 1 (Panx1) channel is a mechanosensitive channel that interacts with P2X7 receptors (P2X7R) to form a functional complex that has been shown in vitro to play an essential role in osteocyte mechanosignaling. While the participation of P2X7R in skeletal responses to mechanical loading has been demonstrated, the role of Panx1 and its interplay with P2X7R still remain to be determined. In this study, we use a global Panx1-/- mouse model and in vivo mechanical loading to demonstrate that Panx1 channels play an essential role in load-induced skeletal responses. We found that absence of Panx1 not only disrupts the P2X7R-Panx1 signaling complex, but also alters load-induced regulation of P2X7R expression. Moreover, lack of Panx1 completely abolished load-induced periosteal bone formation. Load-induced regulation of β-catenin and sclerostin expression was dysregulated in Panx1-/- , compared to wild-type, bone. This finding suggests that Panx1 deficiency disrupts Wnt/β-catenin signaling by lowering β-catenin while favoring inhibition of bone formation by increasing load-induced sclerostin expression. This study demonstrates the existence of a Panx1-dependent mechanosensitive mechanism that not only modulates ATP signaling but also coordinates Wnt/β-catenin signaling that is essential for proper skeletal response to mechanical loading.
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Affiliation(s)
- Zeynep Seref-Ferlengez
- Department of Orthopaedic Surgery.,Laboratories of Musculoskeletal Orthopedic Research at Einstein-Montefiore (MORE)
| | - Marcia Urban-Maldonado
- Department of Orthopaedic Surgery.,Laboratories of Musculoskeletal Orthopedic Research at Einstein-Montefiore (MORE).,Department of Urology
| | - Hui B Sun
- Department of Orthopaedic Surgery.,Laboratories of Musculoskeletal Orthopedic Research at Einstein-Montefiore (MORE).,Department of Radiation Oncology
| | - Mitchell B Schaffler
- Department of Biomedical Engineering, City College of New York, New York, New York
| | - Sylvia O Suadicani
- Laboratories of Musculoskeletal Orthopedic Research at Einstein-Montefiore (MORE).,Department of Urology.,Department of Neuroscience, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
| | - Mia M Thi
- Department of Orthopaedic Surgery.,Laboratories of Musculoskeletal Orthopedic Research at Einstein-Montefiore (MORE).,Department of Neuroscience, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
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Makarenkova HP, Shah SB, Shestopalov VI. The two faces of pannexins: new roles in inflammation and repair. J Inflamm Res 2018; 11:273-288. [PMID: 29950881 PMCID: PMC6016592 DOI: 10.2147/jir.s128401] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Pannexins belong to a family of ATP-release channels expressed in almost all cell types. An increasing body of literature on pannexins suggests that these channels play dual and sometimes contradictory roles, contributing to normal cell function, as well as to the pathological progression of disease. In this review, we summarize our understanding of pannexin "protective" and "harmful" functions in inflammation, regeneration and mechanical signaling. We also suggest a possible basis for pannexin's dual roles, related to extracellular ATP and K+ levels and the activation of various types of P2 receptors that are associated with pannexin. Finally, we speculate upon therapeutic strategies related to pannexin using eyes, lacrimal glands, and peripheral nerves as examples of interesting therapeutic targets.
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Affiliation(s)
| | - Sameer B Shah
- Departments of Orthopaedic Surgery and Bioengineering, University of California.,Research Division, Veterans Affairs San Diego Healthcare System, San Diego, CA
| | - Valery I Shestopalov
- Bascom Eye Institute, Department of Ophthalmology, University of Miami, Miami, FL, USA.,Vavilov Institute for General Genetics, Russian Academy of Sciences.,Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia
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29
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Role of Inflammasomes in Neuroimmune and Neurodegenerative Diseases: A Systematic Review. Mediators Inflamm 2018; 2018:1549549. [PMID: 29849483 PMCID: PMC5932495 DOI: 10.1155/2018/1549549] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 12/26/2017] [Accepted: 01/01/2018] [Indexed: 12/31/2022] Open
Abstract
Inflammasomes are multiprotein complexes that can sense pathogen-associated molecular patterns and damage-associated molecular signals. They are involved in the initiation and development of inflammation via activation of IL-1β and IL-18. Many recent studies suggest a strong correlation between inflammasomes and neurological diseases, such as multiple sclerosis (MS), Alzheimer's disease (AD), and Parkinson's disease (PD). Several components of inflammasomes, such as nucleotide-binding oligomerization domain- (NOD-) like receptor, absent in melanoma 2- (AIM2-) like receptors (ALRs), apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and caspase-1, as well as the upstream factors and downstream effectors, are associated with the initiation and development of MS and its animal model, experimental autoimmune encephalomyelitis. Additionally, inflammasomes affect the efficacy of interferon-β therapy in patients with MS. Finally, the strong association of inflammasomes with AD and PD needs to be further studied. In this review of latest literatures, we comprehensively tease out diverse roles of different kinds of inflammasomes in neuroimmune and neurodegenerative diseases, especially in the perspective of double roles involved in pathogenesis, and identify future research priorities.
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30
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Barclay W, Shinohara ML. Inflammasome activation in multiple sclerosis and experimental autoimmune encephalomyelitis (EAE). Brain Pathol 2018; 27:213-219. [PMID: 27997058 DOI: 10.1111/bpa.12477] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 12/14/2016] [Indexed: 12/19/2022] Open
Abstract
The aptly named inflammasomes are powerful signaling complexes that sense inflammatory signals under a myriad of conditions, including those from infections and endogenous sources. The inflammasomes promote inflammation by maturation and release of the pro-inflammatory cytokines, IL-1β and IL-18. Several inflammasomes have been identified so far, but this review focuses mainly on the NLRP3 inflammasome. By still ill-defined activation mechanisms, a sensor molecule, NLRP3 (NACHT, LRR and PYD domains-containing protein 3), responds to danger signals and rapidly recruits ASC (apoptosis-associated speck-like protein containing a CARD) and pro-caspase-1 to form a large oligomeric signaling platform-the inflammasome. Involvement of the NLRP3 inflammasome in infections, metabolic disorders, autoinflammation, and autoimmunity, underscores its position as a central player in sensing microbial and damage signals and coordinating pro-inflammatory immune responses. Indeed, evidence in patients with multiple sclerosis (MS) suggests inflammasome activation occurs during disease. Experiments with the mouse model of MS, experimental autoimmune encephalomyelitis (EAE), specifically describe the NLRP3 inflammasome as critical and necessary to disease development. This review discusses recent studies in EAE and MS which describe associations of inflammasome activation with promotion of T cell pathogenicity, infiltration of cells into the central nervous system (CNS) and direct neurodegeneration during EAE and MS.
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Affiliation(s)
- William Barclay
- Department of Immunology, Duke University Medical School, Durham, NC
| | - Mari L Shinohara
- Department of Immunology, Duke University Medical School, Durham, NC.,Department of Molecular Genetics and Microbiology, Duke University Medical School, Durham, NC
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31
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Colombo F, Bastoni M, Nigro A, Podini P, Finardi A, Casella G, Ramesh M, Farina C, Verderio C, Furlan R. Cytokines Stimulate the Release of Microvesicles from Myeloid Cells Independently from the P2X7 Receptor/Acid Sphingomyelinase Pathway. Front Immunol 2018; 9:204. [PMID: 29467770 PMCID: PMC5808348 DOI: 10.3389/fimmu.2018.00204] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 01/24/2018] [Indexed: 11/28/2022] Open
Abstract
Microvesicles (MVs) are membrane particles of 200–500 nm released by all cell types constitutively. MVs of myeloid origin are found increased in the cerebrospinal fluid (CSF) of patients suffering from neuroinflammatory disorders, although the factors triggering their production have never been defined. Here, we report that both pro- and anti-inflammatory cytokines, specifically interferon-γ and interleukin-4, are equally able to stimulate the production of MVs from microglia cells and monocytes. Additionally, we found this process to be independent from the best characterized molecular pathway so far described for membrane shedding, which is centered on the purinergic receptor P2X7, whose activation by high concentrations of extracellular ATP (exATP) results in membrane blebbing operated by the secreted enzyme acid sphingomyelinase (ASMase). Moreover, a potent inhibitor of ASMase, injected in a mouse model of multiple sclerosis, failed to reduce the number of MVs in their CSF. This suggests that cytokines, rather than exATP, may exert a long-term control of MV production in the context of chronic inflammation, where both pro- and anti-inflammatory factors play coordinated roles.
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Affiliation(s)
- Federico Colombo
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
| | - Mattia Bastoni
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
| | - Annamaria Nigro
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
| | - Paola Podini
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
| | - Annamaria Finardi
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
| | - Giacomo Casella
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
| | - Menon Ramesh
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
| | - Cinthia Farina
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
| | | | - Roberto Furlan
- Department of Neuroscience and INSPE, San Raffaele Scientific Institute, Milano, Italy
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32
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Hainz N, Wolf S, Beck A, Wagenpfeil S, Tschernig T, Meier C. Probenecid arrests the progression of pronounced clinical symptoms in a mouse model of multiple sclerosis. Sci Rep 2017; 7:17214. [PMID: 29222419 PMCID: PMC5722901 DOI: 10.1038/s41598-017-17517-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 11/27/2017] [Indexed: 12/05/2022] Open
Abstract
While it has been established that Probenecid (PBN) prevents the onset of experimental autoimmune encephalomyelitis (EAE) in mice, it is not clear whether it has any effect on already manifest EAE. The aim of this study was therefore to analyze the therapeutic effect of PBN in pronounced EAE. Mice with manifest clinical symptoms of EAE were either treated with PBN or solvent for 20 days, or they were left untreated. The clinical symptoms were monitored daily. Inflammation, demyelination and oligodendrocyte numbers were determined in the spinal cord. We were able to demonstrate that PBN not only significantly prolonged survival but also prevented the progression of clinical symptoms in the EAE model of multiple sclerosis. In addition, we were able to show that PBN reduced inflammation, T cell infiltration and oligodendrocyte cell loss. PBN was previously shown to inhibit – among other targets – pannexin channels. As pannexin channels provide conduits for ATP, are associated with the inflammasome, and act as “find me-signals” in the process of apoptosis, inhibition of pannexins via PBN might contribute to the PBN-effects observed in this study. The beneficial and therapeutic effects of PBN in the context of EAE demonstrate an intriguing link between PBN and neuroinflammation, which might foster translational interest.
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Affiliation(s)
- Nadine Hainz
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Sandra Wolf
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Artjom Beck
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Stefan Wagenpfeil
- Institute for Medical Biometry, Epidemiology & Medical Informatics, Saarland University, Homburg/Saar, Germany
| | - Thomas Tschernig
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany
| | - Carola Meier
- Dept. of Anatomy and Cell Biology, Saarland University, Homburg/Saar, Germany.
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33
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Basova LV, Tang X, Umasume T, Gromova A, Zyrianova T, Shmushkovich T, Wolfson A, Hawley D, Zoukhri D, Shestopalov VI, Makarenkova HP. Manipulation of Panx1 Activity Increases the Engraftment of Transplanted Lacrimal Gland Epithelial Progenitor Cells. Invest Ophthalmol Vis Sci 2017; 58:5654-5665. [PMID: 29098296 PMCID: PMC5678547 DOI: 10.1167/iovs.17-22071] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Purpose Sjögren's syndrome is a systemic chronic autoimmune inflammatory disease that primarily targets the salivary and lacrimal glands (LGs). Currently there is no cure; therefore, cell-based regenerative therapy may be a viable option. LG inflammation is facilitated by extracellular ATP and mediated by the Pannexin-1 (Panx1) membrane channel glycoprotein. We propose that suppression of inflammation through manipulation of Panx1 activity can stimulate epithelial cell progenitor (EPCP) engraftment. Methods The expression of pannexins in the mouse and human LG was assayed by qRT-PCR and immunostaining. Acute LG inflammation was induced by interleukin-1α (IL1α) injection. Prior to EPCP transplantation, IL1α-injured or chronically inflamed LGs of thrombospondin-1–null mice (TSP-1−/−) were treated with the Panx1-specific blocking peptide (10panx) or the self-deliverable RNAi (sdRNAi). The efficacy of cell engraftment and the area of inflammation were analyzed by microscopy. Results Panx1 and Panx2 were detected in the mouse and human LGs. Panx1 and proinflammatory factors were upregulated during acute inflammation at days 1 to 3 after the IL1α injection. The analysis of EPCP engraftment demonstrated a significant and reproducible positive correlation between the 10panx peptide or Panx1 sdRNAi treatment and the number of engrafted cells. Similarly, treatment of the LG of the TSP-1−/− mouse (mouse model of chronic LG inflammation) by either Panx1 or Caspase-4 (also known as Casp11) sdRNAi showed a significant decrease in expression of proinflammatory markers and the lymphocyte infiltration. Conclusions Our results suggest that blocking Panx1 and/or Casp4 activities is a beneficial strategy to enhance donor cell engraftment and LG regeneration through the reduction of inflammation.
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Affiliation(s)
- Liana V Basova
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Xin Tang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Takeshi Umasume
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Anastasia Gromova
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Tatiana Zyrianova
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | | | | | - Dillon Hawley
- Department of Comprehensive Care, Tufts University School of Dental Medicine, Boston, Massachusetts, United States
| | - Driss Zoukhri
- Department of Comprehensive Care, Tufts University School of Dental Medicine, Boston, Massachusetts, United States.,Department of Ophthalmology, Tufts University School of Medicine, Boston, Massachusetts, United States
| | - Valery I Shestopalov
- Bascom Palmer Eye Institute Department of Ophthalmology, University of Miami School of Medicine, Miami, Florida, United States.,Department of Cell Biology, University of Miami School of Medicine, Miami, Florida, United States
| | - Helen P Makarenkova
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
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34
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Lecca D, Fumagalli M, Ceruti S, Abbracchio MP. Intertwining extracellular nucleotides and their receptors with Ca2+ in determining adult neural stem cell survival, proliferation and final fate. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0433. [PMID: 27377726 DOI: 10.1098/rstb.2015.0433] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2016] [Indexed: 02/07/2023] Open
Abstract
In the central nervous system (CNS), during both brain and spinal cord development, purinergic and pyrimidinergic signalling molecules (ATP, UTP and adenosine) act synergistically with peptidic growth factors in regulating the synchronized proliferation and final specification of multipotent neural stem cells (NSCs) to neurons, astrocytes or oligodendrocytes, the myelin-forming cells. Some NSCs still persist throughout adulthood in both specific 'neurogenic' areas and in brain and spinal cord parenchyma, retaining the potentiality to generate all the three main types of adult CNS cells. Once CNS anatomical structures are defined, purinergic molecules participate in calcium-dependent neuron-to-glia communication and also control the behaviour of adult NSCs. After development, some purinergic mechanisms are silenced, but can be resumed after injury, suggesting a role for purinergic signalling in regeneration and self-repair also via the reactivation of adult NSCs. In this respect, at least three different types of adult NSCs participate in the response of the adult brain and spinal cord to insults: stem-like cells residing in classical neurogenic niches, in particular, in the ventricular-subventricular zone (V-SVZ), parenchymal oligodendrocyte precursor cells (OPCs, also known as NG2-glia) and parenchymal injury-activated astrocytes (reactive astrocytes). Here, we shall review and discuss the purinergic regulation of these three main adult NSCs, with particular focus on how and to what extent modulation of intracellular calcium levels by purinoceptors is mandatory to determine their survival, proliferation and final fate.This article is part of the themed issue 'Evolution brings Ca(2+) and ATP together to control life and death'.
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Affiliation(s)
- Davide Lecca
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy
| | - Marta Fumagalli
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy
| | - Stefania Ceruti
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy
| | - Maria P Abbracchio
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, 20133 Milan, Italy
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35
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Molica F, Meens MJ, Dubrot J, Ehrlich A, Roth CL, Morel S, Pelli G, Vinet L, Braunersreuther V, Ratib O, Chanson M, Hugues S, Scemes E, Kwak BR. Pannexin1 links lymphatic function to lipid metabolism and atherosclerosis. Sci Rep 2017; 7:13706. [PMID: 29057961 PMCID: PMC5651868 DOI: 10.1038/s41598-017-14130-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 10/06/2017] [Indexed: 12/29/2022] Open
Abstract
Extracellular ATP is a central signaling molecule in inflammatory responses. Pannexin1 (Panx1) channels release ATP in a controlled manner and have been implicated in various inflammatory pathologies, but their role in atherogenesis remains elusive. Using atherosclerosis-susceptible mouse models with ubiquitous deletion of Panx1 (Panx1−/−Apoe−/−) or with Cre recombinase-mediated deletion of Panx1 in endothelial cells and monocytes (Tie2-CreTgPanx1fl/flApoe−/−; Panx1delApoe−/−), we identified a novel role for Panx1 in the lymphatic vasculature. Atherosclerotic lesion development in response to high-cholesterol diet was enhanced in Panx1delApoe−/− mice, pointing to an atheroprotective role for Panx1 in endothelial and/or monocytic cells. Unexpectedly, atherogenesis was not changed in mice with ubiquitous Panx1 deletion, but Panx1−/−Apoe−/− mice displayed reduced body weight, serum cholesterol, triglycerides and free fatty acids, suggesting altered lipid metabolism in these Panx1-deficient mice. Mechanistically, Panx1−/−Apoe−/− mice showed impairment of lymphatic vessel function with decreased drainage of interstitial fluids and reduced dietary fat absorption. Thus, the detrimental effect of Panx1 deletion in endothelial and/or monocytic cells during atherogenesis is counterbalanced by an opposite effect resulting from impaired lymphatic function in ubiquitous Panx1-deficient mice. Collectively, our findings unveil a pivotal role of Panx1 in linking lymphatic function to lipid metabolism and atherosclerotic plaque development.
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Affiliation(s)
- Filippo Molica
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland
| | - Merlijn J Meens
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland
| | - Juan Dubrot
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland
| | - Avigail Ehrlich
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland
| | - Christel L Roth
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland
| | - Sandrine Morel
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland
| | - Graziano Pelli
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland
| | - Laurent Vinet
- Geneva University Hospitals, Department of Radiology and Medical Informatics, Geneva, CH-1211, Switzerland.,University of Geneva and Lausanne, School of Pharmaceutical Sciences, Geneva, CH-1211, Switzerland
| | | | - Osman Ratib
- Geneva University Hospitals, Department of Radiology and Medical Informatics, Geneva, CH-1211, Switzerland
| | - Marc Chanson
- Geneva University Hospitals and University of Geneva, Department of Pediatrics and of Cell Physiology and Metabolism, Geneva, CH-1211, Switzerland
| | - Stephanie Hugues
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland
| | - Eliana Scemes
- Albert Einstein College of Medicine, Department of Neuroscience, New York, NY, 10461, USA
| | - Brenda R Kwak
- University of Geneva, Department of Pathology and Immunology, Geneva, CH-1211, Switzerland. .,University of Geneva, Department of Medical Specializations - Cardiology, Geneva, CH-1211, Switzerland.
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36
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Shestopalov VI, Panchin Y, Tarasova OS, Gaynullina D, Kovalzon VM. Pannexins Are Potential New Players in the Regulation of Cerebral Homeostasis during Sleep-Wake Cycle. Front Cell Neurosci 2017; 11:210. [PMID: 28769767 PMCID: PMC5511838 DOI: 10.3389/fncel.2017.00210] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 07/03/2017] [Indexed: 12/18/2022] Open
Abstract
During brain homeostasis, both neurons and astroglia release ATP that is rapidly converted to adenosine in the extracellular space. Pannexin-1 (Panx1) hemichannels represent a major conduit of non-vesicular ATP release from brain cells. Previous studies have shown that Panx1−/− mice possess severe disruption of the sleep-wake cycle. Here, we review experimental data supporting the involvement of pannexins (Panx) in the coordination of fundamental sleep-associated brain processes, such as neuronal activity and regulation of cerebrovascular tone. Panx1 hemichannels are likely implicated in the regulation of the sleep-wake cycle via an indirect effect of released ATP on adenosine receptors and through interaction with other somnogens, such as IL-1β, TNFα and prostaglandin D2. In addition to the recently established role of Panx1 in the regulation of endothelium-dependent arterial dilation, similar signaling pathways are the major cellular component of neurovascular coupling. The new discovered role of Panx in sleep regulation may have broad implications in coordinating neuronal activity and homeostatic housekeeping processes during the sleep-wake cycle.
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Affiliation(s)
- Valery I Shestopalov
- Institute for Information Transmission Problems, Russian Academy of SciencesMoscow, Russia.,Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of MedicineMiami, FL, United States.,Microbiology and Bioengineering Laboratory, Department of Genomics and Biotechnology, Vavilov Institute of General Genetics, Russian Academy of SciencesMoscow, Russia
| | - Yuri Panchin
- Institute for Information Transmission Problems, Russian Academy of SciencesMoscow, Russia.,Department of Mathematical Methods in Biology, Belozersky Institute, M.V. Lomonosov Moscow State UniversityMoscow, Russia
| | - Olga S Tarasova
- Institute for Information Transmission Problems, Russian Academy of SciencesMoscow, Russia.,Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State UniversityMoscow, Russia.,State Research Center of the Russian Federation, Institute for Biomedical Problems, Russian Academy of SciencesMoscow, Russia
| | - Dina Gaynullina
- Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State UniversityMoscow, Russia.,Department of Physiology, Russian National Research Medical UniversityMoscow, Russia
| | - Vladimir M Kovalzon
- Institute for Information Transmission Problems, Russian Academy of SciencesMoscow, Russia.,Severtsov Institute Ecology and Evolution, Russian Academy of SciencesMoscow, Russia
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FGF-1 Triggers Pannexin-1 Hemichannel Opening in Spinal Astrocytes of Rodents and Promotes Inflammatory Responses in Acute Spinal Cord Slices. J Neurosci 2017; 36:4785-801. [PMID: 27122036 DOI: 10.1523/jneurosci.4195-15.2016] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/16/2016] [Indexed: 12/30/2022] Open
Abstract
UNLABELLED We show here that the growth factor FGF-1 is proinflammatory in the spinal cord and explore the inflammatory mechanisms. FGF-1 applied to rat spinal astrocytes in culture initiates calcium signaling and induces secretion of ATP that within minutes increases membrane permeability to ethidium (Etd(+)) and Ca(2+) by activating P2X7 receptors (P2X7Rs) that open pannexin hemichannels (Px1 HCs) that release further ATP; by 7 h treatment, connexin 43 hemichannels (Cx43 HCs) are also opened. In acute mouse spinal cord slices ex vivo, we found that FGF-1 treatment for 1 h increases the percentage of GFAP-positive astrocytes that show enhanced Px1 HC-mediated Etd(+) uptake. This response to FGF-1 was not observed in astrocytes in slices of cerebral cortex. FGF-1-induced dye uptake by astrocytes is prevented by BAPTA-AM or a phospholipase C (PLC) inhibitor. Furthermore, in spinal cord slices, P2X7R antagonists (BBG and A740003) and Px1 HC blockers ((10)Panx1 and carbenoxolone) prevent the increase in Etd(+) uptake by astrocytes, whereas Gap19, a selective Cx43 HC blocker, has no effect on dye uptake at this time. Microglia are not required for the increase in Etd(+) uptake by astrocytes induced by FGF-1, although they are activated by FGF-1 treatment. The morphological signs of microglia activation are inhibited by P2X7R antagonists and (10)Panx1 and are associated with elevated levels of proinflammatory cytokines in cord slices treated with FGF-1. The FGF-1 initiated cascade may play an important role in spinal cord inflammation in vivo SIGNIFICANCE STATEMENT We find that FGF-1 elevates [Ca(2+)]i in spinal astrocytes, which causes vesicular release of ATP and activation of P2X7Rs to trigger opening of Px1 HCs, which release further ATP. This regenerative response occurs in astrocyte cultures and in acute spinal cord slices. In the latter, FGF-1 application promotes the activation of microglia and increases the production of proinflammatory cytokines through mechanisms depending on P2X7 receptors and Px1 HCs. This proinflammatory microenvironment may favor recruitment of leukocytes into the spinal cord and impacts negatively on neuronal structure and function in vivo Any step in these processes provides a potential therapeutic target for treatment of secondary damage in various spinal cord pathologies.
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Endothelial Wnt/β-catenin signaling reduces immune cell infiltration in multiple sclerosis. Proc Natl Acad Sci U S A 2017; 114:E1168-E1177. [PMID: 28137846 DOI: 10.1073/pnas.1609905114] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Disruption of the blood-brain barrier (BBB) is a defining and early feature of multiple sclerosis (MS) that directly damages the central nervous system (CNS), promotes immune cell infiltration, and influences clinical outcomes. There is an urgent need for new therapies to protect and restore BBB function, either by strengthening endothelial tight junctions or suppressing endothelial vesicular transcytosis. Although wingless integrated MMTV (Wnt)/β-catenin signaling plays an essential role in BBB formation and maintenance in healthy CNS, its role in BBB repair in neurologic diseases such as MS remains unclear. Using a Wnt/β-catenin reporter mouse and several downstream targets, we demonstrate that the Wnt/β-catenin pathway is up-regulated in CNS endothelial cells in both human MS and the mouse model experimental autoimmune encephalomyelitis (EAE). Increased Wnt/β-catenin activity in CNS blood vessels during EAE progression correlates with up-regulation of neuronal Wnt3 expression, as well as breakdown of endothelial cell junctions. Genetic inhibition of the Wnt/β-catenin pathway in CNS endothelium before disease onset exacerbates the clinical presentation of EAE, CD4+ T-cell infiltration into the CNS, and demyelination by increasing expression of vascular cell adhesion molecule-1 and the transcytosis protein Caveolin-1 and promoting endothelial transcytosis. However, Wnt signaling attenuation does not affect the progressive degradation of tight junction proteins or paracellular BBB leakage. These results suggest that reactivation of Wnt/β-catenin signaling in CNS vessels during EAE/MS partially restores functional BBB integrity and limits immune cell infiltration into the CNS.
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Hainz N, Wolf S, Tschernig T, Meier C. Probenecid Application Prevents Clinical Symptoms and Inflammation in Experimental Autoimmune Encephalomyelitis. Inflammation 2016; 39:123-128. [PMID: 26276126 DOI: 10.1007/s10753-015-0230-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system. Neurological impairments are caused by axonal damage due to demyelination and neuroinflammation within the central nervous system. T cells mediate the neuroinflammation. The activation of T cells is induced by the release of adenosine triphosphate and involves purinergic receptors as well as pannexin (Panx) proteins. As Panx1 is expressed on T cells, we here propose that application of probenecid, a known Panx inhibitor, will prevent the onset of clinical symptoms in a mouse model of MS, the experimental autoimmune encephalomyelitis (EAE) model. EAE-induced mice received daily injections of probenecid. Disease scores, T cell numbers, and microglia activation were compared between experimental groups. Probenecid treatment resulted in lower disease scores as compared to EAE animals. Probenecid-treated animals also displayed fewer inflammatory lesions. Microglia activation was not altered by treatment. In conclusion, probenecid prevented the onset of EAE.
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Affiliation(s)
- Nadine Hainz
- Department of Anatomy and Cell Biology, Saarland University, Building 61, 66421, Homburg, Saar, Germany
| | - Sandra Wolf
- Department of Anatomy and Cell Biology, Saarland University, Building 61, 66421, Homburg, Saar, Germany
| | - Thomas Tschernig
- Department of Anatomy and Cell Biology, Saarland University, Building 61, 66421, Homburg, Saar, Germany
| | - Carola Meier
- Department of Anatomy and Cell Biology, Saarland University, Building 61, 66421, Homburg, Saar, Germany.
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40
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Diezmos EF, Bertrand PP, Liu L. Purinergic Signaling in Gut Inflammation: The Role of Connexins and Pannexins. Front Neurosci 2016; 10:311. [PMID: 27445679 PMCID: PMC4925662 DOI: 10.3389/fnins.2016.00311] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/20/2016] [Indexed: 12/13/2022] Open
Abstract
Purinergic receptors play an important role in inflammation, and can be activated by ATP released via pannexin channels and/or connexin hemichannels. The purinergic P2X7 receptor (P2X7R) is of interest since it is involved in apoptosis when activated. Most studies focus on the influence of pannexin-1 (Panx1) and connexin 43 (Cx43) on ATP release and how it affects P2X7R function during inflammation. Inflammatory bowel disease (IBD) is characterized by uncontrolled inflammation within the gastrointestinal system. At present, the pathophysiology of this disease remains largely unknown but it may involve the interplay between P2X7R, Panx1, and Cx43. There are two main types of IBD, ulcerative colitis and Crohn's disease, that are classified by their location and frequency of inflammation. Current research suggests that alterations to normal functioning of innate and adaptive immunity may be a factor in disease progression. The involvement of purinergic receptors, connexins, and pannexins in IBD is a relatively novel notion in the context of gastrointestinal inflammation, and has been explored by various research groups. Thus, the present review focuses on the current research involving connexins, pannexins, and purinergic receptors within the gut and enteric nervous system, and will examine their involvement in inflammation and the pathophysiology of IBD.
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Affiliation(s)
- Erica F Diezmos
- School of Medical Sciences, University of New South Wales Sydney, NSW, Australia
| | - Paul P Bertrand
- School of Medical Sciences, University of New South WalesSydney, NSW, Australia; School of Medical Sciences, RMIT UniversityBundoora, VIC, Australia
| | - Lu Liu
- School of Medical Sciences, University of New South Wales Sydney, NSW, Australia
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Abstract
Communication among cells via direct cell-cell contact by connexin gap junctions, or between cell and extracellular environment via pannexin channels or connexin hemichannels, is a key factor in cell function and tissue homeostasis. Upon malignant transformation in different cancer types, the dysregulation of these connexin and pannexin channels and their effect in cellular communication, can either enhance or suppress tumorigenesis and metastasis. In this review, we will highlight the latest reports on the role of the well characterized connexin family and its ability to form gap junctions and hemichannels in cancer. We will also introduce the more recently discovered family of pannexin channels and our current knowledge about their involvement in cancer progression.
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Affiliation(s)
- Jean X Jiang
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, 78229, USA
| | - Silvia Penuela
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, N6A5C1, Canada.
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42
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Velasquez S, Malik S, Lutz SE, Scemes E, Eugenin EA. Pannexin1 Channels Are Required for Chemokine-Mediated Migration of CD4+ T Lymphocytes: Role in Inflammation and Experimental Autoimmune Encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2016; 196:4338-47. [PMID: 27076682 DOI: 10.4049/jimmunol.1502440] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 03/09/2016] [Indexed: 12/19/2022]
Abstract
Pannexin1 (Panx1) channels are large high conductance channels found in all vertebrates that can be activated under several physiological and pathological conditions. Our published data indicate that HIV infection results in the extended opening of Panx1 channels (5-60 min), allowing for the secretion of ATP through the channel pore with subsequent activation of purinergic receptors, which facilitates HIV entry and replication. In this article, we demonstrate that chemokines, which bind CCR5 and CXCR4, especially SDF-1α/CXCL12, result in a transient opening (peak at 5 min) of Panx1 channels found on CD4(+) T lymphocytes, which induces ATP secretion, focal adhesion kinase phosphorylation, cell polarization, and subsequent migration. Increased migration of immune cells is key for the pathogenesis of several inflammatory diseases including multiple sclerosis (MS). In this study, we show that genetic deletion of Panx1 reduces the number of the CD4(+) T lymphocytes migrating into the spinal cord of mice subjected to experimental autoimmune encephalomyelitis, an animal model of MS. Our results indicate that opening of Panx1 channels in response to chemokines is required for CD4(+) T lymphocyte migration, and we propose that targeting Panx1 channels could provide new potential therapeutic approaches to decrease the devastating effects of MS and other inflammatory diseases.
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Affiliation(s)
- Stephani Velasquez
- Public Health Research Institute, Rutgers New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ 07103; Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ 07103
| | - Shaily Malik
- Public Health Research Institute, Rutgers New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ 07103; Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ 07103
| | - Sarah E Lutz
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697; and
| | - Eliana Scemes
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Eliseo A Eugenin
- Public Health Research Institute, Rutgers New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ 07103; Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ 07103;
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43
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The clearance of dying cells: table for two. Cell Death Differ 2016; 23:915-26. [PMID: 26990661 PMCID: PMC4987729 DOI: 10.1038/cdd.2015.172] [Citation(s) in RCA: 191] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 12/15/2015] [Accepted: 12/16/2015] [Indexed: 12/19/2022] Open
Abstract
Phagocytic cells of the immune system must constantly survey for, recognize, and efficiently clear the billions of cellular corpses that arise as a result of development, stress, infection, or normal homeostasis. This process, termed efferocytosis, is critical for the prevention of autoimmune and inflammatory disorders, and persistence of dead cells in tissue is characteristic of many human autoimmune diseases, notably systemic lupus erythematosus. The most notable characteristic of the efferocytosis of apoptotic cells is its ‘immunologically silent' response. Although the mechanisms by which phagocytes facilitate engulfment of dead cells has been a well-studied area, the pathways that coordinate to process the ingested corpse and direct the subsequent immune response is an area of growing interest. The recently described pathway of LC3 (microtubule-associated protein 1A/1B-light chain 3)-associated phagocytosis (LAP) has shed some light on this issue. LAP is triggered when an extracellular particle, such as a dead cell, engages an extracellular receptor during phagocytosis, induces the translocation of autophagy machinery, and ultimately LC3 to the cargo-containing phagosome, termed the LAPosome. In this review, we will examine efferocytosis and the impact of LAP on efferocytosis, allowing us to reimagine the impact of the autophagy machinery on innate host defense mechanisms.
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Do not let death do us part: 'find-me' signals in communication between dying cells and the phagocytes. Cell Death Differ 2016; 23:979-89. [PMID: 26891690 DOI: 10.1038/cdd.2016.13] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 01/04/2016] [Accepted: 01/07/2016] [Indexed: 12/12/2022] Open
Abstract
The turnover and clearance of cells is an essential process that is part of many physiological and pathological processes. Improper or deficient clearance of apoptotic cells can lead to excessive inflammation and autoimmune disease. The steps involved in cell clearance include: migration of the phagocyte toward the proximity of the dying cells, specific recognition and internalization of the dying cell, and degradation of the corpse. The ability of phagocytes to recognize and react to dying cells to perform efficient and immunologically silent engulfment has been well-characterized in vitro and in vivo. However, how apoptotic cells themselves initiate the corpse removal and also influence the cells within the neighboring environment during clearance was less understood. Recent exciting observations suggest that apoptotic cells can attract phagocytes through the regulated release of 'find-me' signals. More recent studies also suggest that these find-me signals can have additional roles outside of phagocyte attraction to help orchestrate engulfment. This review will discuss our current understanding of the different find-me signals released by apoptotic cells, how they may be relevant in vivo, and their additional roles in facilitating engulfment.
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45
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Central nervous system myeloid cells as drug targets: current status and translational challenges. Nat Rev Drug Discov 2015; 15:110-24. [DOI: 10.1038/nrd.2015.14] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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46
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Emerging role of P2X7 receptors in CNS health and disease. Ageing Res Rev 2015; 24:328-42. [PMID: 26478005 DOI: 10.1016/j.arr.2015.10.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 10/05/2015] [Indexed: 12/11/2022]
Abstract
Purinergic signalling in the brain is becoming an important focus in the study of CNS health and disease. Various purinergic receptors are found to be present in different brain cells in varying extent, which get activated upon binding of ATP or its analogues. Conventionally, ATP was considered only as a major metabolic fuel of the cell but its recognition as a neurotransmitter in early 1970s, brought meaningful insights in neuron glia crosstalk, participating in various physiological functions in the brain. P2X7R, a member of ligand gated purinergic receptor (P2X) family, is gaining attention in the field of neuroscience because of its emerging role in broad spectrum of ageing and age related neurological disorders. The aim of this review is to provide an overview about the structure and function of P2X7R highlighting its unique features which distinguish it from the other members of its family. This review critically analyzes the literature mentioning the details about the agonist and antagonist of the P2X7R. It also emphasizes the advancements in understanding the dual role of P2X7R in brain development and disorders inviting meaningful insights about its involvement in Alzheimer's disease, Huntington's disease, Multiple Sclerosis, Neuropathic pain, Spinal Cord Injury and NeuroAIDS. Exploring the roles of P2X7R in detail is critical to identify its therapeutic potential in the treatment of acute and chronic neurodegenerative diseases. Moreover, this review also helps to raise more interest in the neurobiology of the purinergic receptors and thus providing new avenues for future research.
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P2X and P2Y receptors—role in the pathophysiology of the nervous system. Int J Mol Sci 2014; 15:23672-704. [PMID: 25530618 PMCID: PMC4284787 DOI: 10.3390/ijms151223672] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 12/03/2014] [Accepted: 12/06/2014] [Indexed: 12/16/2022] Open
Abstract
Purinergic signalling plays a crucial role in proper functioning of the nervous system. Mechanisms depending on extracellular nucleotides and their P2 receptors also underlie a number of nervous system dysfunctions. This review aims to present the role of purinergic signalling, with particular focus devoted to role of P2 family receptors, in epilepsy, depression, neuropathic pain, nervous system neoplasms, such as glioma and neuroblastoma, neurodegenerative diseases like Parkinson’s disease, Alzheimer’s disease and multiple sclerosis. The above-mentioned conditions are associated with changes in expression of extracellular ectonucleotidases, P2X and P2Y receptors in neurons and glial cells, as well as releasing considerable amounts of nucleotides from activated or damaged nervous tissue cells into the extracellular space, which contributes to disturbance in purinergic signalling. The numerous studies indicate a potential possibility of using synthetic agonists/antagonists of P2 receptors in treatment of selected nervous system diseases. This is of particular significance, since numerous available agents reveal a low effectiveness and often produce side effects.
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48
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Zoidl G, Spray DC. Gap junctional communication in health and disease. Front Physiol 2014; 5:442. [PMID: 25484867 PMCID: PMC4240040 DOI: 10.3389/fphys.2014.00442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 10/29/2014] [Indexed: 01/14/2023] Open
Affiliation(s)
- Georg Zoidl
- Department of Psychology, York University Toronto, ON, Canada
| | - David C Spray
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine of Yeshiva University New York, NY, USA
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49
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Abstract
In less than a decade, a small family of channel-forming glycoproteins, named pannexins, have captured the interest of many biologists, in large part due to their association with common diseases, ranging from cancers to neuropathies to infectious diseases. Although the pannexin family consists of only three members (Panx1, Panx2 and Panx3), one or more of these pannexins are expressed in virtually every mammalian organ, implicating their potential role in a diverse array of pathophysiologies. Panx1 is the most extensively studied, but features of this pannexin must be cautiously extrapolated to the other pannexins, as for example we now know that Panx2, unlike Panx1, exhibits unique properties such as a tendency to be retained within intracellular compartments. In the present review, we assess the biochemical and channel features of pannexins focusing on the literature which links these unique molecules to over a dozen diseases and syndromes. Although no germ-line mutations in genes encoding pannexins have been linked to any diseases, many cases have shown that high pannexin expression is associated with disease onset and/or progression. Disease may also occur, however, when pannexins are underexpressed, highlighting that pannexin expression must be exquisitely regulated. Finally, we discuss some of the most pressing questions and controversies in the pannexin field as the community seeks to uncover the full biological relevance of pannexins in healthy organs and during disease.
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50
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Kurtenbach S, Whyte-Fagundes P, Gelis L, Kurtenbach S, Brazil E, Zoidl C, Hatt H, Shestopalov VI, Zoidl G. Investigation of olfactory function in a Panx1 knock out mouse model. Front Cell Neurosci 2014; 8:266. [PMID: 25309319 PMCID: PMC4162419 DOI: 10.3389/fncel.2014.00266] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 08/18/2014] [Indexed: 01/01/2023] Open
Abstract
Pannexin 1 (Panx1), the most extensively investigated member of a channel-forming protein family, is able to form pores conducting molecules up to 1.5 kDa, like ATP, upon activation. In the olfactory epithelium (OE), ATP modulates olfactory responsiveness and plays a role in proliferation and differentiation of olfactory sensory neurons (OSNs). This process continuously takes place in the OE, as neurons are replaced throughout the whole lifespan. The recent discovery of Panx1 expression in the OE raises the question whether Panx1 mediates ATP release responsible for modulating chemosensory function. In this study, we analyzed pannexin expression in the OE and a possible role of Panx1 in olfactory function using a Panx1−/− mouse line with a global ablation of Panx1. This mouse model has been previously used to investigate Panx1 functions in the retina and adult hippocampus. Here, qPCR, in-situ hybridization, and immunohistochemistry (IHC) demonstrated that Panx1 is expressed in axon bundles deriving from sensory neurons of the OE. The localization, distribution, and expression of major olfactory signal transduction proteins were not significantly altered in Panx1−/− mice. Further, functional analysis of Panx1−/− animals does not reveal any major impairment in odor perception, indicated by electroolfactogram (EOG) measurements and behavioral testing. However, ATP release evoked by potassium gluconate application was reduced in Panx1−/− mice. This result is consistent with previous reports on ATP release in isolated erythrocytes and spinal or lumbar cord preparations from Panx1−/− mice, suggesting that Panx1 is one of several alternative pathways to release ATP in the olfactory system.
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Affiliation(s)
- Stefan Kurtenbach
- Department of Psychology, Faculty of Health, York University Toronto, ON, Canada
| | - Paige Whyte-Fagundes
- Department of Psychology, Faculty of Health, York University Toronto, ON, Canada
| | - Lian Gelis
- Department of Cell Physiology, Ruhr University Bochum Bochum, Germany
| | - Sarah Kurtenbach
- Department of Psychology, Faculty of Health, York University Toronto, ON, Canada
| | - Emerson Brazil
- Department of Psychology, Faculty of Health, York University Toronto, ON, Canada
| | - Christiane Zoidl
- Department of Psychology, Faculty of Health, York University Toronto, ON, Canada
| | - Hanns Hatt
- Department of Cell Physiology, Ruhr University Bochum Bochum, Germany
| | - Valery I Shestopalov
- Department of Ophthalmology, Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami Miami, FL, USA ; Vavilov Institute of General Genetics, Russian Academy of Sciences Moscow, Russia
| | - Georg Zoidl
- Department of Psychology, Faculty of Health, York University Toronto, ON, Canada
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