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Matus V, Castro-Guarda M, Cárcamo-Fierro J, Morera FJ, Zambrano A. Interleukin 3 Inhibits Glutamate-Cytotoxicity in Neuroblastoma Cell Line. Neurochem Res 2024; 49:1373-1386. [PMID: 38512424 DOI: 10.1007/s11064-024-04123-x] [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: 09/23/2023] [Revised: 01/06/2024] [Accepted: 02/06/2024] [Indexed: 03/23/2024]
Abstract
Interleukin 3 (IL-3) is a well-known pleiotropic cytokine that regulates the proliferation and differentiation of hematopoietic progenitor cells, triggering classical signaling pathways such as JAK/STAT, Ras/MAPK, and PI3K/Akt to carry out its functions. Interestingly, the IL-3 receptor is also expressed in non-hematopoietic cells, playing a crucial role in cell survival. Our previous research demonstrated the expression of the IL-3 receptor in neuron cells and its protective role in neurodegeneration. Glutamate, a principal neurotransmitter in the central nervous system, can induce cellular stress and lead to neurotoxicity when its extracellular concentrations surpass normal levels. This excessive glutamate presence is frequently observed in various neurological diseases. In this study, we uncover the protective role of IL-3 as an inhibitor of glutamate-induced cell death, analyzing the cytokine's signaling pathways during its protective effect. Specifically, we examined the relevance of JAK/STAT, Ras/MAPK, and PI3 K signaling pathways in the molecular mechanism triggered by IL-3. Our results show that the inhibition of JAK, ERK, and PI3 K signaling pathways, using pharmacological inhibitors, effectively blocked IL-3's protective role against glutamate-induced cell death. Additionally, our findings suggest that Bcl-2 and Bax proteins may be involved in the molecular mechanism triggered by IL-3. Our investigation into IL-3's ability to protect neuronal cells from glutamate-induced damage offers a promising therapeutic avenue with potential clinical implications for several neurological diseases characterized by glutamate neurotoxicity.
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Affiliation(s)
- Verónica Matus
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, (P. O. Box) 567, 5090000, Casilla, Valdivia, Chile
| | - Marcos Castro-Guarda
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, (P. O. Box) 567, 5090000, Casilla, Valdivia, Chile
| | - Joaquín Cárcamo-Fierro
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, (P. O. Box) 567, 5090000, Casilla, Valdivia, Chile
| | - Francisco J Morera
- Applied Biochemistry Laboratory, Escuela de Medicina Veterinaria, Facultad de Agronomía y Sistemas Naturales, Facultad de Ciencias Biológicas y Facultad de Medicina, Pontificia Universidad Católica de Chile, 7820436, Santiago, Chile
| | - Angara Zambrano
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, (P. O. Box) 567, 5090000, Casilla, Valdivia, Chile.
- Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile.
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2
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Assis-de-Lemos G, Moura-do-Nascimento R, Amaral-do-Nascimento M, Miceli AC, Vieira TCRG. Interactions between Cytokines and the Pathogenesis of Prion Diseases: Insights and Implications. Brain Sci 2024; 14:413. [PMID: 38790392 PMCID: PMC11117815 DOI: 10.3390/brainsci14050413] [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: 03/20/2024] [Revised: 04/16/2024] [Accepted: 04/21/2024] [Indexed: 05/26/2024] Open
Abstract
Transmissible Spongiform Encephalopathies (TSEs), including prion diseases such as Bovine Spongiform Encephalopathy (Mad Cow Disease) and variant Creutzfeldt-Jakob Disease, pose unique challenges to the scientific and medical communities due to their infectious nature, neurodegenerative effects, and the absence of a cure. Central to the progression of TSEs is the conversion of the normal cellular prion protein (PrPC) into its infectious scrapie form (PrPSc), leading to neurodegeneration through a complex interplay involving the immune system. This review elucidates the current understanding of the immune response in prion diseases, emphasizing the dual role of the immune system in both propagating and mitigating the disease through mechanisms such as glial activation, cytokine release, and blood-brain barrier dynamics. We highlight the differential cytokine profiles associated with various prion strains and stages of disease, pointing towards the potential for cytokines as biomarkers and therapeutic targets. Immunomodulatory strategies are discussed as promising avenues for mitigating neuroinflammation and delaying disease progression. This comprehensive examination of the immune response in TSEs not only advances our understanding of these enigmatic diseases but also sheds light on broader neuroinflammatory processes, offering hope for future therapeutic interventions.
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Affiliation(s)
| | | | | | | | - Tuane C. R. G. Vieira
- Institute of Medical Biochemistry Leopoldo de Meis and National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (G.A.-d.-L.); (R.M.-d.-N.); (M.A.-d.-N.); (A.C.M.)
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3
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Yates AG, Khamhoung A, McAlpine CS. Interleukin-3 gets a fresh start in the brain. Genes Immun 2023; 24:289-291. [PMID: 38066341 PMCID: PMC11021124 DOI: 10.1038/s41435-023-00231-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/02/2023] [Accepted: 11/08/2023] [Indexed: 12/18/2023]
Affiliation(s)
- Abi G Yates
- Cardiovascular Research Institute and the Department of Medicine, Cardiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute and the Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Annie Khamhoung
- Cardiovascular Research Institute and the Department of Medicine, Cardiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute and the Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Cameron S McAlpine
- Cardiovascular Research Institute and the Department of Medicine, Cardiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Friedman Brain Institute and the Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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4
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Lomoio S, Pandey RS, Rouleau N, Menicacci B, Kim W, Cantley WL, Haydon PG, Bennett DA, Young-Pearse TL, Carter GW, Kaplan DL, Tesco G. 3D bioengineered neural tissue generated from patient-derived iPSCs mimics time-dependent phenotypes and transcriptional features of Alzheimer's disease. Mol Psychiatry 2023; 28:5390-5401. [PMID: 37365240 PMCID: PMC11164539 DOI: 10.1038/s41380-023-02147-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 05/31/2023] [Accepted: 06/16/2023] [Indexed: 06/28/2023]
Abstract
Several iPSC-derived three-dimensional (3D) cultures have been generated to model Alzheimer's disease (AD). While some AD-related phenotypes have been identified across these cultures, none of them could recapitulate multiple AD-related hallmarks in one model. To date, the transcriptomic features of these 3D models have not been compared with those of human AD brains. However, these data are crucial to understanding the pertinency of these models for studying AD-related pathomechanisms over time. We developed a 3D bioengineered model of iPSC-derived neural tissue that combines a porous scaffold composed of silk fibroin protein with an intercalated collagen hydrogel to support the growth of neurons and glial cells into complex and functional networks for an extended time, a fundamental requisite for aging studies. Cultures were generated from iPSC lines obtained from two subjects carrying the familial AD (FAD) APP London mutation, two well-studied control lines, and an isogenic control. Cultures were analyzed at 2 and 4.5 months. At both time points, an elevated Aβ42/40 ratio was detected in conditioned media from FAD cultures. However, extracellular Aβ42 deposition and enhanced neuronal excitability were observed in FAD culture only at 4.5 months, suggesting that extracellular Aβ deposition may trigger enhanced network activity. Remarkably, neuronal hyperexcitability has been described in AD patients early in the disease. Transcriptomic analysis revealed the deregulation of multiple gene sets in FAD samples. Such alterations were strikingly similar to those observed in human AD brains. These data provide evidence that our patient-derived FAD model develops time-dependent AD-related phenotypes and establishes a temporal relation among them. Furthermore, FAD iPSC-derived cultures recapitulate transcriptomic features of AD patients. Thus, our bioengineered neural tissue represents a unique tool to model AD in vitro over time.
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Affiliation(s)
- Selene Lomoio
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Ravi S Pandey
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Nicolas Rouleau
- Department of Health Sciences, Wilfrid Laurier University, Waterloo, Canada
| | - Beatrice Menicacci
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - WonHee Kim
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - William L Cantley
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | - Philip G Haydon
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Tracy L Young-Pearse
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Gregory W Carter
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
- The Jackson Laboratory, Bar Harbor, ME, USA
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | - Giuseppina Tesco
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA.
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5
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Denes V, Lukats A, Szarka G, Subicz R, Mester A, Kovacs-Valasek A, Geck P, Berta G, Herczeg R, Postyeni E, Gyenesei A, Gabriel R. Long-term Effects of the pituitary-adenylate cyclase-activating Polypeptide (PACAP38) in the Adult Mouse Retina: Microglial Activation and Induction of Neural Proliferation. Neurochem Res 2023; 48:3430-3446. [PMID: 37466802 PMCID: PMC10514177 DOI: 10.1007/s11064-023-03989-7] [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: 04/06/2023] [Revised: 07/01/2023] [Accepted: 07/07/2023] [Indexed: 07/20/2023]
Abstract
The degenerative retinal disorders characterized by progressive cell death and exacerbating inflammation lead ultimately to blindness. The ubiquitous neuropeptide, PACAP38 is a promising therapeutic agent as its proliferative potential and suppressive effect on microglia might enable cell replacement and attenuate inflammation, respectively. Our previous finding that PACAP38 caused a marked increase of the amacrine cells in the adult (1-year-old) mouse retina, served as a rationale of the current study. We aimed to determine the proliferating elements and the inflammatory status of the PACAP38-treated retina. Three months old mice were intravitreally injected with 100 pmol PACAP38 at 3 months intervals (3X). Retinas of 1-year-old animals were dissected and effects on cell proliferation, and expression of inflammatory regulators were analyzed. Interestingly, both mitogenic and anti-mitogenic actions were detected after PACAP38-treatment. Further analysis of the mitogenic effect revealed that proliferating cells include microglia, endothelial cells, and neurons of the ganglion cell layer but not amacrine cells. Furthermore, PACAP38 stimulated retinal microglia to polarize dominantly into M2-phenotype but also might cause subsequent angiogenesis. According to our results, PACAP38 might dampen pro-inflammatory responses and help tissue repair by reprogramming microglia into an M2 phenotype, nonetheless, with angiogenesis as a warning side effect.
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Affiliation(s)
- Viktoria Denes
- Department of Neurobiology, University of Pécs, 6 Ifjúság str, Pécs, H-7624, Hungary.
| | - Akos Lukats
- Institute of Translational Medicine, Translational Retina Research Group, Semmelweis University, Budapest, Hungary
| | - Gergely Szarka
- Department of Neurobiology, University of Pécs, 6 Ifjúság str, Pécs, H-7624, Hungary
| | - Rovena Subicz
- Department of Neurobiology, University of Pécs, 6 Ifjúság str, Pécs, H-7624, Hungary
| | - Adrienn Mester
- Department of Neurobiology, University of Pécs, 6 Ifjúság str, Pécs, H-7624, Hungary
| | - Andrea Kovacs-Valasek
- Department of Neurobiology, University of Pécs, 6 Ifjúság str, Pécs, H-7624, Hungary
| | - Peter Geck
- Department of Medical Education, School of Medicine, Tufts University, 136 Harrison Ave, Boston, MA, 02111, USA
| | - Gergely Berta
- Department of Medical Biology and Central Electron Microscope Laboratory, Medical School, University of Pécs, Pécs, Hungary
| | - Robert Herczeg
- János Szentágothai Research Centre, Bioinformatics Research Group, University of Pécs, 20 Ifjúság str, Pécs, H-7624, Hungary
| | - Etelka Postyeni
- Department of Neurobiology, University of Pécs, 6 Ifjúság str, Pécs, H-7624, Hungary
| | - Attila Gyenesei
- János Szentágothai Research Centre, Bioinformatics Research Group, University of Pécs, 20 Ifjúság str, Pécs, H-7624, Hungary
| | - Robert Gabriel
- Department of Neurobiology, University of Pécs, 6 Ifjúság str, Pécs, H-7624, Hungary
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6
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Boahen A, Hu D, Adams MJ, Nicholls PK, Greene WK, Ma B. Bidirectional crosstalk between the peripheral nervous system and lymphoid tissues/organs. Front Immunol 2023; 14:1254054. [PMID: 37767094 PMCID: PMC10520967 DOI: 10.3389/fimmu.2023.1254054] [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: 07/06/2023] [Accepted: 08/25/2023] [Indexed: 09/29/2023] Open
Abstract
The central nervous system (CNS) influences the immune system generally by regulating the systemic concentration of humoral substances (e.g., cortisol and epinephrine), whereas the peripheral nervous system (PNS) communicates specifically with the immune system according to local interactions/connections. An imbalance between the components of the PNS might contribute to pathogenesis and the further development of certain diseases. In this review, we have explored the "thread" (hardwiring) of the connections between the immune system (e.g., primary/secondary/tertiary lymphoid tissues/organs) and PNS (e.g., sensory, sympathetic, parasympathetic, and enteric nervous systems (ENS)) in health and disease in vitro and in vivo. Neuroimmune cell units provide an anatomical and physiological basis for bidirectional crosstalk between the PNS and the immune system in peripheral tissues, including lymphoid tissues and organs. These neuroimmune interactions/modulation studies might greatly contribute to a better understanding of the mechanisms through which the PNS possibly affects cellular and humoral-mediated immune responses or vice versa in health and diseases. Physical, chemical, pharmacological, and other manipulations of these neuroimmune interactions should bring about the development of practical therapeutic applications for certain neurological, neuroimmunological, infectious, inflammatory, and immunological disorders/diseases.
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Affiliation(s)
- Angela Boahen
- Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Seri-Kembangan, Selangor, Malaysia
| | - Dailun Hu
- Department of Pathogenic Biology, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Murray J. Adams
- School of Medical, Molecular and Forensic Sciences, Murdoch University, Murdoch, WA, Australia
| | - Philip K. Nicholls
- School of Medical, Molecular and Forensic Sciences, Murdoch University, Murdoch, WA, Australia
| | - Wayne K. Greene
- School of Medical, Molecular and Forensic Sciences, Murdoch University, Murdoch, WA, Australia
| | - Bin Ma
- School of Medical, Molecular and Forensic Sciences, Murdoch University, Murdoch, WA, Australia
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7
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Pham JH, Stankowska DL. Mitochondria-associated endoplasmic reticulum membranes (MAMs) and their role in glaucomatous retinal ganglion cell degeneration-a mini review. Front Neurosci 2023; 17:1198343. [PMID: 37250427 PMCID: PMC10213334 DOI: 10.3389/fnins.2023.1198343] [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: 04/01/2023] [Accepted: 04/24/2023] [Indexed: 05/31/2023] Open
Abstract
Glaucoma is a leading cause of blindness worldwide, commonly associated with elevated intraocular pressure (IOP), leading to degeneration of the optic nerve and death of retinal ganglion cells, the output neurons in the eye. In recent years, many studies have implicated mitochondrial dysfunction as a crucial player in glaucomatous neurodegeneration. Mitochondrial function has been an increasingly researched topic in glaucoma, given its vital role in bioenergetics and propagation of action potentials. One of the most metabolically active tissues in the body characterized by high oxygen consumption is the retina, particularly the retinal ganglion cells (RGCs). RGCs, which have long axons that extend from the eyes to the brain, rely heavily on the energy generated by oxidative phosphorylation for signal transduction, rendering them more vulnerable to oxidative damage. In various glaucoma models, mitochondrial dysfunction and stress from protein aggregates in the endoplasmic reticulum (ER) have been observed in the RGCs. However, it has been shown that the two organelles are connected through a network called mitochondria-associated ER membranes (MAMs); hence this crosstalk in a pathophysiological condition such as glaucoma should be evaluated. Here, we review the current literature suggestive of mitochondrial and ER stress related to glaucoma, indicating potential cross-signaling and the potential roles of MAMs.
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Affiliation(s)
- Jennifer H. Pham
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Dorota L. Stankowska
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, United States
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8
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Chiarini A, Gui L, Viviani C, Armato U, Dal Prà I. NLRP3 Inflammasome’s Activation in Acute and Chronic Brain Diseases—An Update on Pathogenetic Mechanisms and Therapeutic Perspectives with Respect to Other Inflammasomes. Biomedicines 2023; 11:biomedicines11040999. [PMID: 37189617 DOI: 10.3390/biomedicines11040999] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/16/2023] [Accepted: 03/17/2023] [Indexed: 03/29/2023] Open
Abstract
Increasingly prevalent acute and chronic human brain diseases are scourges for the elderly. Besides the lack of therapies, these ailments share a neuroinflammation that is triggered/sustained by different innate immunity-related protein oligomers called inflammasomes. Relevant neuroinflammation players such as microglia/monocytes typically exhibit a strong NLRP3 inflammasome activation. Hence the idea that NLRP3 suppression might solve neurodegenerative ailments. Here we review the recent Literature about this topic. First, we update conditions and mechanisms, including RNAs, extracellular vesicles/exosomes, endogenous compounds, and ethnic/pharmacological agents/extracts regulating NLRP3 function. Second, we pinpoint NLRP3-activating mechanisms and known NLRP3 inhibition effects in acute (ischemia, stroke, hemorrhage), chronic (Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, MS, ALS), and virus-induced (Zika, SARS-CoV-2, and others) human brain diseases. The available data show that (i) disease-specific divergent mechanisms activate the (mainly animal) brains NLRP3; (ii) no evidence proves that NLRP3 inhibition modifies human brain diseases (yet ad hoc trials are ongoing); and (iii) no findings exclude that concurrently activated other-than-NLRP3 inflammasomes might functionally replace the inhibited NLRP3. Finally, we highlight that among the causes of the persistent lack of therapies are the species difference problem in disease models and a preference for symptomatic over etiologic therapeutic approaches. Therefore, we posit that human neural cell-based disease models could drive etiological, pathogenetic, and therapeutic advances, including NLRP3’s and other inflammasomes’ regulation, while minimizing failure risks in candidate drug trials.
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9
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Zappelli E, Daniele S, Vergassola M, Ceccarelli L, Chelucci E, Mangano G, Durando L, Ragni L, Martini C. A specific combination of nutraceutical Ingredients exerts cytoprotective effects in human cholinergic neurons. PHARMANUTRITION 2022. [DOI: 10.1016/j.phanu.2022.100317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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10
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Chronic Chemogenetic Activation of the Superior Colliculus in Glaucomatous Mice: Local and Retrograde Molecular Signature. Cells 2022; 11:cells11111784. [PMID: 35681479 PMCID: PMC9179903 DOI: 10.3390/cells11111784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 05/20/2022] [Accepted: 05/22/2022] [Indexed: 12/13/2022] Open
Abstract
One important facet of glaucoma pathophysiology is axonal damage, which ultimately disrupts the connection between the retina and its postsynaptic brain targets. The concurrent loss of retrograde support interferes with the functionality and survival of the retinal ganglion cells (RGCs). Previous research has shown that stimulation of neuronal activity in a primary retinal target area—i.e., the superior colliculus—promotes RGC survival in an acute mouse model of glaucoma. To build further on this observation, we applied repeated chemogenetics in the superior colliculus of a more chronic murine glaucoma model—i.e., the microbead occlusion model—and performed bulk RNA sequencing on collicular lysates and isolated RGCs. Our study revealed that chronic target stimulation upon glaucomatous injury phenocopies the a priori expected molecular response: growth factors were pinpointed as essential transcriptional regulators both in the locally stimulated tissue and in distant, unstimulated RGCs. Strikingly, and although the RGC transcriptome revealed a partial reversal of the glaucomatous signature and an enrichment of pro-survival signaling pathways, functional rescue of injured RGCs was not achieved. By postulating various explanations for the lack of RGC neuroprotection, we aim to warrant researchers and drug developers for the complexity of chronic neuromodulation and growth factor signaling.
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11
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Li K, Ly K, Mehta S, Braithwaite A. Importance of crosstalk between the microbiota and the neuroimmune system for tissue homeostasis. Clin Transl Immunology 2022; 11:e1394. [PMID: 35620584 PMCID: PMC9125509 DOI: 10.1002/cti2.1394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 04/30/2022] [Accepted: 05/01/2022] [Indexed: 11/23/2022] Open
Abstract
The principal function of inflammation is cellular defence against ‘danger signals’ such as tissue injury and pathogen infection to maintain the homeostasis of the organism. The initiation and progression of inflammation are not autonomous as there is substantial evidence that inflammation is known to be strongly influenced by ‘neuroimmune crosstalk’, involving the production and expression of soluble signalling molecules that interact with cell surface receptors. In addition, microbiota have been found to be involved in the development and function of the nervous and immune systems and play an important role in health and disease. Herein, we provide an outline of the mechanisms of neuroimmune communication in the regulation of inflammation and immune response and then provide evidence for the involvement of microbiota in the development and functions of the host nervous and immune systems. It appears that the nervous and immune systems in multicellular organisms have co‐evolved with the microbiota, such that all components are in communication to maximise the ability of the organism to adapt to a wide range of environmental stresses to maintain or restore tissue homeostasis.
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Affiliation(s)
- Kunyu Li
- Department of Pathology Dunedin School of Medicine University of Otago Dunedin New Zealand
| | - Kevin Ly
- Department of Pathology Dunedin School of Medicine University of Otago Dunedin New Zealand
| | - Sunali Mehta
- Department of Pathology Dunedin School of Medicine University of Otago Dunedin New Zealand
| | - Antony Braithwaite
- Department of Pathology Dunedin School of Medicine University of Otago Dunedin New Zealand
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12
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Acioglu C, Heary RF, Elkabes S. Roles of neuronal toll-like receptors in neuropathic pain and central nervous system injuries and diseases. Brain Behav Immun 2022; 102:163-178. [PMID: 35176442 DOI: 10.1016/j.bbi.2022.02.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/12/2022] [Accepted: 02/11/2022] [Indexed: 12/12/2022] Open
Abstract
Toll-like receptors (TLRs) are innate immune receptors that are expressed in immune cells as well as glia and neurons of the central and peripheral nervous systems. They are best known for their role in the host defense in response to pathogens and for the induction of inflammation in infectious and non-infectious diseases. In the central nervous system (CNS), TLRs modulate glial and neuronal functions as well as innate immunity and neuroinflammation under physiological or pathophysiological conditions. The majority of the studies on TLRs in CNS pathologies investigated their overall contribution without focusing on a particular cell type, or they analyzed TLRs in glia and infiltrating immune cells in the context of neuroinflammation and cellular activation. The role of neuronal TLRs in CNS diseases and injuries has received little attention and remains underappreciated. The primary goal of this review is to summarize findings demonstrating the pivotal and unique roles of neuronal TLRs in neuropathic pain, Alzheimer's disease, Parkinson's disease and CNS injuries. We discuss how the current findings warrant future investigations to better define the specific contributions of neuronal TLRs to these pathologies. We underline the paucity of information regarding the role of neuronal TLRs in other neurodegenerative, demyelinating, and psychiatric diseases. We draw attention to the importance of broadening research on neuronal TLRs in view of emerging evidence demonstrating their distinctive functional properties.
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Affiliation(s)
- Cigdem Acioglu
- The Reynolds Family Spine Laboratory, Department of Neurosurgery, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103, United States
| | - Robert F Heary
- Department of Neurological Surgery, Hackensack Meridian School of Medicine, Mountainside Medical Center, Montclair, NJ 07042, United States
| | - Stella Elkabes
- The Reynolds Family Spine Laboratory, Department of Neurosurgery, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103, United States.
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13
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Abstract
Klotho gene was originally recognized as a putative aging-suppressor and its prominent age-regulating effects are mostly attributed to the modulation of mineral homeostasis in the kidney. However, recent studies link alterations in hippocampal Klotho expression with cognitive impairment and neurodegenerative diseases. This suggests that hippocampal neurons require Klotho for health and proper functionality. Klotho protects against neuronal dysfunction and regulates several intracellular signaling pathways including oxidative stress response, inflammation, DNA damage, autophagy, endoplasmic reticulum stress response, and multiple types of cell death. Specifically, this chapter covers the current knowledge as to how Klotho protein affects the hippocampal neuronal cells, with special attention paid to underlying molecular mechanisms, and thus influences hippocampal development, hippocampal-dependent cognition, behavior, and motor skills as well as mediates neurodegenerative processes.
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Affiliation(s)
- Jennifer Mytych
- Department of Biotechnology, Institute of Biology and Biotechnology, Collegium Scientarium Naturalium, University of Rzeszow, Werynia, Poland.
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14
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Sarker B, Cardona SM, Church KA, Vanegas D, Velazquez P, Rorex C, Rodriguez D, Mendiola AS, Kern TS, Domingo ND, Stephens R, Muzzio IA, Cardona AE. Defibrinogenation Ameliorates Retinal Microgliosis and Inflammation in A CX3CR1-Independent Manner. ASN Neuro 2022; 14:17590914221131446. [PMID: 36221892 PMCID: PMC9557863 DOI: 10.1177/17590914221131446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/14/2022] [Accepted: 09/20/2022] [Indexed: 11/05/2022] Open
Abstract
SUMMARY STATEMENT Diabetic human and murine retinas revealed pronounced microglial morphological activation and vascular abnormalities associated with inflammation. Pharmacological fibrinogen depletion using ancrod dampened microglial morphology alterations, resolved fibrinogen accumulation, rescued axonal integrity, and reduced inflammation in the diabetic murine retina.
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Affiliation(s)
- Borna Sarker
- Department of Molecular Microbiology and Immunology,
The University
of Texas at San Antonio, San Antonio, TX,
USA
- South Texas Center for Emerging Infectious Diseases,
The University
of Texas at San Antonio, San Antonio, TX,
USA
| | - Sandra M. Cardona
- Department of Molecular Microbiology and Immunology,
The University
of Texas at San Antonio, San Antonio, TX,
USA
- South Texas Center for Emerging Infectious Diseases,
The University
of Texas at San Antonio, San Antonio, TX,
USA
| | - Kaira A. Church
- Department of Molecular Microbiology and Immunology,
The University
of Texas at San Antonio, San Antonio, TX,
USA
- South Texas Center for Emerging Infectious Diseases,
The University
of Texas at San Antonio, San Antonio, TX,
USA
| | - Difernando Vanegas
- Department of Molecular Microbiology and Immunology,
The University
of Texas at San Antonio, San Antonio, TX,
USA
- South Texas Center for Emerging Infectious Diseases,
The University
of Texas at San Antonio, San Antonio, TX,
USA
| | - Priscila Velazquez
- Department of Molecular Microbiology and Immunology,
The University
of Texas at San Antonio, San Antonio, TX,
USA
- South Texas Center for Emerging Infectious Diseases,
The University
of Texas at San Antonio, San Antonio, TX,
USA
| | - Colin Rorex
- Department of Molecular Microbiology and Immunology,
The University
of Texas at San Antonio, San Antonio, TX,
USA
- South Texas Center for Emerging Infectious Diseases,
The University
of Texas at San Antonio, San Antonio, TX,
USA
| | - Derek Rodriguez
- Department of Molecular Microbiology and Immunology,
The University
of Texas at San Antonio, San Antonio, TX,
USA
- South Texas Center for Emerging Infectious Diseases,
The University
of Texas at San Antonio, San Antonio, TX,
USA
| | | | - Timothy S. Kern
- Department of Ophthalmology, Gavin Herbert Eye
Institute, University of California-Irvine,
Irvine, CA, USA
- Veterans Administration Medical Center Research Service, Long Beach,
CA, USA
| | - Nadia D. Domingo
- Rutgers Center of Immunity and Inflammation,
Rutgers New
Jersey Medical School, Newark, NJ,
USA
| | - Robin Stephens
- Rutgers Center of Immunity and Inflammation,
Rutgers New
Jersey Medical School, Newark, NJ,
USA
- Department of Pharmacology, Physiology and Neuroscience, Rutgers
Center of Immunity and Inflammation, Rutgers New Jersey Medical
School, Newark, NJ, USA
| | - Isabel A. Muzzio
- Department of Psychological and Brain Sciences, The University of
Iowa, Iowa City, IA, USA
| | - Astrid E. Cardona
- Department of Molecular Microbiology and Immunology,
The University
of Texas at San Antonio, San Antonio, TX,
USA
- South Texas Center for Emerging Infectious Diseases,
The University
of Texas at San Antonio, San Antonio, TX,
USA
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15
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Neuro-immune-metabolism: The tripod system of homeostasis. Immunol Lett 2021; 240:77-97. [PMID: 34655659 DOI: 10.1016/j.imlet.2021.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 09/30/2021] [Accepted: 10/08/2021] [Indexed: 11/20/2022]
Abstract
Homeostatic regulation of cellular and molecular processes is essential for the efficient physiological functioning of body organs. It requires an intricate balance of several networks throughout the body, most notable being the nervous, immune and metabolic systems. Several studies have reported the interactions between neuro-immune, immune-metabolic and neuro-metabolic pathways. Current review aims to integrate the information and show that neuro, immune and metabolic systems form the triumvirate of homeostasis. It focuses on the cellular and molecular interactions occurring in the extremities and intestine, which are innervated by the peripheral nervous system and for the intestine in particular the enteric nervous system. While the interdependence of neuro-immune-metabolic pathways provides a fallback mechanism in case of disruption of homeostasis, in chronic pathologies of continued disequilibrium, the collapse of one system spreads to the other interacting networks as well. Current review illustrates this domino-effect using diabetes as the main example. Together, this review attempts to provide a holistic picture of the integrated network of neuro-immune-metabolism and attempts to broaden the outlook when devising a scientific study or a treatment strategy.
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16
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Campagno KE, Lu W, Jassim AH, Albalawi F, Cenaj A, Tso HY, Clark SP, Sripinun P, Gómez NM, Mitchell CH. Rapid morphologic changes to microglial cells and upregulation of mixed microglial activation state markers induced by P2X7 receptor stimulation and increased intraocular pressure. J Neuroinflammation 2021; 18:217. [PMID: 34544431 PMCID: PMC8454080 DOI: 10.1186/s12974-021-02251-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/25/2021] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The identification of endogenous signals that lead to microglial activation is a key step in understanding neuroinflammatory cascades. As ATP release accompanies mechanical strain to neural tissue, and as the P2X7 receptor for ATP is expressed on microglial cells, we examined the morphological and molecular consequences of P2X7 receptor stimulation in vivo and in vitro and investigated the contribution of the P2X7 receptor in a model of increased intraocular pressure (IOP). METHODS In vivo experiments involved intravitreal injections and both transient and sustained elevation of IOP. In vitro experiments were performed on isolated mouse retinal and brain microglial cells. Morphological changes were quantified in vivo using Sholl analysis. Expression of mRNA for M1- and M2-like genes was determined with qPCR. The luciferin/luciferase assay quantified retinal ATP release while fura-2 indicated cytoplasmic calcium. Microglial migration was monitored with a Boyden chamber. RESULTS Sholl analysis of Iba1-stained cells showed retraction of microglial ramifications 1 day after injection of P2X7 receptor agonist BzATP into mouse retinae. Mean branch length of ramifications also decreased, while cell body size and expression of Nos2, Tnfa, Arg1, and Chil3 mRNA increased. BzATP induced similar morphological changes in ex vivo tissue isolated from Cx3CR1+/GFP mice, suggesting recruitment of external cells was unnecessary. Immunohistochemistry suggested primary microglial cultures expressed the P2X7 receptor, while functional expression was demonstrated with Ca2+ elevation by BzATP and block by specific antagonist A839977. BzATP induced process retraction and cell body enlargement within minutes in isolated microglial cells and increased Nos2 and Arg1. While ATP increased microglial migration, this required the P2Y12 receptor and not P2X7 receptor. Transient elevation of IOP led to microglial process retraction, cell body enlargement, and gene upregulation paralleling changes observed with BzATP injection, in addition to retinal ATP release. Pressure-dependent changes were reduced in P2X7-/- mice. Death of retinal ganglion cells accompanied increased IOP in C57Bl/6J, but not P2X7-/- mice, and neuronal loss showed some association with microglial activation. CONCLUSIONS P2X7 receptor stimulation induced rapid morphological activation of microglial cells, including process retraction and cell body enlargement, and upregulation of markers linked to both M1- and M2-type activation. Parallel responses accompanied IOP elevation, suggesting ATP release and P2X7 receptor stimulation influence the early microglial response to increased pressure.
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Affiliation(s)
- Keith E Campagno
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Wennan Lu
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Assraa Hassan Jassim
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Farraj Albalawi
- Department of Orthodontics, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Preventive Dental Sciences, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Aurora Cenaj
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Huen-Yee Tso
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Sophia P Clark
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Puttipong Sripinun
- Department of Orthodontics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Néstor Más Gómez
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Claire H Mitchell
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA.
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Physiology, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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17
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Immune Responses in the Glaucomatous Retina: Regulation and Dynamics. Cells 2021; 10:cells10081973. [PMID: 34440742 PMCID: PMC8391899 DOI: 10.3390/cells10081973] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 12/27/2022] Open
Abstract
Glaucoma is a multifactorial disease resulting in progressive vision loss due to retinal ganglion cell (RGC) dysfunction and death. Early events in the pathobiology of the disease include oxidative, metabolic, or mechanical stress that acts upon RGC, causing these to rapidly release danger signals, including extracellular ATP, resulting in micro- and macroglial activation and neuroinflammation. Danger signaling also leads to the formation of inflammasomes in the retina that enable maturation of proinflammatory cytokines such IL-1β and IL-18. Chronic neuroinflammation can have directly damaging effects on RGC, but it also creates a proinflammatory environment and compromises the immune privilege of the retina. In particular, continuous synthesis of proinflammatory mediators such as TNFα, IL-1β, and anaphylatoxins weakens the blood–retina barrier and recruits or activates T-cells. Recent data have demonstrated that adaptive immune responses strongly exacerbate RGC loss in animal models of the disease as T-cells appear to target heat shock proteins displayed on the surface of stressed RGC to cause their apoptotic death. It is possible that dysregulation of these immune responses contributes to the continued loss of RGC in some patients.
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18
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Jassim AH, Inman DM, Mitchell CH. Crosstalk Between Dysfunctional Mitochondria and Inflammation in Glaucomatous Neurodegeneration. Front Pharmacol 2021; 12:699623. [PMID: 34366851 PMCID: PMC8334009 DOI: 10.3389/fphar.2021.699623] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 06/22/2021] [Indexed: 12/11/2022] Open
Abstract
Mitochondrial dysfunction and excessive inflammatory responses are both sufficient to induce pathology in age-dependent neurodegenerations. However, emerging evidence indicates crosstalk between damaged mitochondrial and inflammatory signaling can exacerbate issues in chronic neurodegenerations. This review discusses evidence for the interaction between mitochondrial damage and inflammation, with a focus on glaucomatous neurodegeneration, and proposes that positive feedback resulting from this crosstalk drives pathology. Mitochondrial dysfunction exacerbates inflammatory signaling in multiple ways. Damaged mitochondrial DNA is a damage-associated molecular pattern, which activates the NLRP3 inflammasome; priming and activation of the NLRP3 inflammasome, and the resulting liberation of IL-1β and IL-18 via the gasdermin D pore, is a major pathway to enhance inflammatory responses. The rise in reactive oxygen species induced by mitochondrial damage also activates inflammatory pathways, while blockage of Complex enzymes is sufficient to increase inflammatory signaling. Impaired mitophagy contributes to inflammation as the inability to turnover mitochondria in a timely manner increases levels of ROS and damaged mtDNA, with the latter likely to stimulate the cGAS-STING pathway to increase interferon signaling. Mitochondrial associated ER membrane contacts and the mitochondria-associated adaptor molecule MAVS can activate NLRP3 inflammasome signaling. In addition to dysfunctional mitochondria increasing inflammation, the corollary also occurs, with inflammation reducing mitochondrial function and ATP production; the resulting downward spiral accelerates degeneration. Evidence from several preclinical models including the DBA/2J mouse, microbead injection and transient elevation of IOP, in addition to patient data, implicates both mitochondrial damage and inflammation in glaucomatous neurodegeneration. The pressure-dependent hypoxia and the resulting metabolic vulnerability is associated with mitochondrial damage and IL-1β release. Links between mitochondrial dysfunction and inflammation can occur in retinal ganglion cells, microglia cells and astrocytes. In summary, crosstalk between damaged mitochondria and increased inflammatory signaling enhances pathology in glaucomatous neurodegeneration, with implications for other complex age-dependent neurodegenerations like Alzheimer's and Parkinson's disease.
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Affiliation(s)
- Assraa Hassan Jassim
- Department of Basic and Translational Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Denise M. Inman
- Department of Pharmaceutical Sciences, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Claire H. Mitchell
- Department of Basic and Translational Science, University of Pennsylvania, Philadelphia, PA, United States
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, United States
- Department of Physiology, University of Pennsylvania, Philadelphia, PA, United States
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19
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P2X7 receptor in multifaceted cellular signalling and its relevance as a potential therapeutic target in different diseases. Eur J Pharmacol 2021; 906:174235. [PMID: 34097884 DOI: 10.1016/j.ejphar.2021.174235] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/28/2021] [Accepted: 06/02/2021] [Indexed: 02/07/2023]
Abstract
P2X7 receptor, a purinergic receptor family member, is abundantly expressed on many cells, including immune, muscle, bone, neuron, and glia. It acts as an ATP-activated cation channel that permits the influx of Ca2+, Na+ and efflux of K+ ions. The P2X7 receptor plays crucial roles in many physiological processes including cytokine and chemokine secretion, NLRP3 inflammasome activation, cellular growth and differentiation, locomotion, wound healing, transcription factors activation, cell death and T-lymphocyte survival. Past studies have demonstrated the up-regulation and direct association of this receptor in many pathophysiological conditions such as cancer, diabetics, arthritis, tuberculosis (TB) and inflammatory diseases. Hence, targeting this receptor is considered a worthwhile approach to lessen the afflictions associated with the disorders mentioned above by understanding the receptor architecture and downstream signalling processes. Here, in the present review, we have dissected the structural and functional aspects of the P2X7 receptor, emphasizing its role in various diseased conditions. This information will provide in-depth knowledge about the receptor and help to develop apt curative methodologies for the betterment of humanity in the coming years.
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20
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Campagno KE, Mitchell CH. The P2X 7 Receptor in Microglial Cells Modulates the Endolysosomal Axis, Autophagy, and Phagocytosis. Front Cell Neurosci 2021; 15:645244. [PMID: 33790743 PMCID: PMC8005553 DOI: 10.3389/fncel.2021.645244] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/22/2021] [Indexed: 01/18/2023] Open
Abstract
Microglial cells regulate neural homeostasis by coordinating both immune responses and clearance of debris, and the P2X7 receptor for extracellular ATP plays a central role in both functions. The P2X7 receptor is primarily known in microglial cells for its immune signaling and NLRP3 inflammasome activation. However, the receptor also affects the clearance of extracellular and intracellular debris through modifications of lysosomal function, phagocytosis, and autophagy. In the absence of an agonist, the P2X7 receptor acts as a scavenger receptor to phagocytose material. Transient receptor stimulation induces autophagy and increases LC3-II levels, likely through calcium-dependent phosphorylation of AMPK, and activates microglia to an M1 or mixed M1/M2 state. We show an increased expression of Nos2 and Tnfa and a decreased expression of Chil3 (YM1) from primary cultures of brain microglia exposed to high levels of ATP. Sustained stimulation can reduce lysosomal function in microglia by increasing lysosomal pH and slowing autophagosome-lysosome fusion. P2X7 receptor stimulation can also cause lysosomal leakage, and the subsequent rise in cytoplasmic cathepsin B activates the NLRP3 inflammasome leading to caspase-1 cleavage and IL-1β maturation and release. Support for P2X7 receptor activation of the inflammasome following lysosomal leakage comes from data on primary microglia showing IL-1β release following receptor stimulation is inhibited by cathepsin B blocker CA-074. This pathway bridges endolysosomal and inflammatory roles and may provide a key mechanism for the increased inflammation found in age-dependent neurodegenerations characterized by excessive lysosomal accumulations. Regardless of whether the inflammasome is activated via this lysosomal leakage or the better-known K+-efflux pathway, the inflammatory impact of P2X7 receptor stimulation is balanced between the autophagic reduction of inflammasome components and their increase following P2X7-mediated priming. In summary, the P2X7 receptor modulates clearance of extracellular debris by microglial cells and mediates lysosomal damage that can activate the NLRP3 inflammasome. A better understanding of how the P2X7 receptor alters phagocytosis, lysosomal health, inflammation, and autophagy can lead to therapies that balance the inflammatory and clearance roles of microglial cells.
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Affiliation(s)
- Keith E Campagno
- Department of Basic and Translational Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Claire H Mitchell
- Department of Basic and Translational Science, University of Pennsylvania, Philadelphia, PA, United States.,Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, United States.,Department of Physiology, University of Pennsylvania, Philadelphia, PA, United States
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21
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Retinal ganglion cell dysfunction in mice following acute intraocular pressure is exacerbated by P2X7 receptor knockout. Sci Rep 2021; 11:4184. [PMID: 33603067 PMCID: PMC7893065 DOI: 10.1038/s41598-021-83669-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/22/2020] [Indexed: 12/21/2022] Open
Abstract
There is increasing evidence for the vulnerability of specific retinal ganglion cell (RGC) types in those with glaucoma and in animal models. In addition, the P2X7-receptor (P2X7-R) has been suggested to contribute to RGC death following stimulation and elevated IOP, though its role in RGC dysfunction prior to death has not been examined. Therefore, we examined the effect of an acute, non-ischemic intraocular pressure (IOP) insult (50 mmHg for 30 min) on RGC function in wildtype mice and P2X7-R knockout (P2X7-KO) mice. We examined retinal function using electroretinogram recordings and individual RGC responses using multielectrode arrays, 3 days following acute IOP elevation. Immunohistochemistry was used to examine RGC cell death and P2X7-R expression in several RGC types. Acute intraocular pressure elevation produced pronounced dysfunction in RGCs; whilst other retinal neuronal responses showed lesser changes. Dysfunction at 3 days post-injury was not associated with RGC loss or changes in receptive field size. However, in wildtype animals, OFF-RGCs showed reduced spontaneous and light-elicited activity. In the P2X7-KO, both ON- and OFF-RGC light-elicited responses were reduced. Expression of P2X7-R in wildtype ON-RGC dendrites was higher than in other RGC types. In conclusion, OFF-RGCs were vulnerable to acute IOP elevation and their dysfunction was not rescued by genetic ablation of P2X7-R. Indeed, knockout of P2X7-R also caused ON-RGC dysfunction. These findings aid our understanding of how pressure affects RGC function and suggest treatments targeting the P2X7-R need to be carefully considered.
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22
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Kampanis V, Tolou-Dabbaghian B, Zhou L, Roth W, Puttagunta R. Cyclic Stretch of Either PNS or CNS Located Nerves Can Stimulate Neurite Outgrowth. Cells 2020; 10:cells10010032. [PMID: 33379276 PMCID: PMC7824691 DOI: 10.3390/cells10010032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 12/15/2022] Open
Abstract
The central nervous system (CNS) does not recover from traumatic axonal injury, but the peripheral nervous system (PNS) does. We hypothesize that this fundamental difference in regenerative capacity may be based upon the absence of stimulatory mechanical forces in the CNS due to the protective rigidity of the vertebral column and skull. We developed a bioreactor to apply low-strain cyclic axonal stretch to adult rat dorsal root ganglia (DRG) connected to either the peripheral or central nerves in an explant model for inducing axonal growth. In response, larger diameter DRG neurons, mechanoreceptors and proprioceptors showed enhanced neurite outgrowth as well as increased Activating Transcription Factor 3 (ATF3).
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Affiliation(s)
- Vasileios Kampanis
- Laboratory for Experimental Neuroregeneration, Spinal Cord Injury Center, Heidelberg University Hospital, 69118 Heidelberg, Germany; (V.K.); (B.T.-D.)
| | - Bahardokht Tolou-Dabbaghian
- Laboratory for Experimental Neuroregeneration, Spinal Cord Injury Center, Heidelberg University Hospital, 69118 Heidelberg, Germany; (V.K.); (B.T.-D.)
| | - Luming Zhou
- Laboratory of NeuroRegeneration and Repair, Hertie Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany;
| | - Wolfgang Roth
- Laboratory for Experimental Neurorehabilitation, Heidelberg University Hospital, 69118 Heidelberg, Germany;
| | - Radhika Puttagunta
- Laboratory for Experimental Neuroregeneration, Spinal Cord Injury Center, Heidelberg University Hospital, 69118 Heidelberg, Germany; (V.K.); (B.T.-D.)
- Correspondence:
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23
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Behroozi Z, Ramezani F, Janzadeh A, Rahimi B, Nasirinezhad F. Platelet-rich plasma in umbilical cord blood reduces neuropathic pain in spinal cord injury by altering the expression of ATP receptors. Physiol Behav 2020; 228:113186. [PMID: 32980385 DOI: 10.1016/j.physbeh.2020.113186] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 12/27/2022]
Abstract
BACKGROUND Neuropathic pain following injury or dysfunction of the peripheral or CNS is one of the most important medical challenges to treat. Humane platelet-rich plasma (HPRP), which is a rich source of growth factors, may be able to treat and reduce pain caused by spinal cord injury (SCI). In this study, the effect of HPRP on neuropathic pain caused by SCI was investigated. METHODS Sixty adult male Wistar rats were randomly divided into 6 groups: control, sham, SCI, vehicle (SCI+platelet-poor plasma), SCI+ PRP2day (injection 48 hrs after SCI) and SCI+PRP14day (injection 14 days after SCI). SCI was induced at the T12-T13 level. Behavioral tests were conducted weekly after injury for six weeks. Allodynia and hyperalgesia were assessed using acetone drops, plantar test and von Frey filament. Cavity size and the number of fibroblasts were determined by H&E stain, and the expression of mTOR, p-mTOR, P2×3R and P2Y4R were determined using the western blot technique. Data were analyzed using PRISM & SPSS software. RESULTS PRP injection showed a higher pain threshold in mechanical allodynia (p<0.0001), cold allodynia (p<0.0001) and thermal hyperalgesia (p<0.0001) than those in the spinal. Animals treated with PRP also reduced cavity size, fibroblast number, p-mTOR/mTOR ratio, and P2×3R expression, and increased P2Y4R expression. The difference between the two groups was not statistically significant. CONCLUSIONS The results showed that PRP reduced SCI-induced allodynia and hyperalgesia by regulating ATP signaling. Using HPRP can open a new window in the treatment of pain caused by damage to the nervous system.
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Affiliation(s)
- Zahra Behroozi
- Student research committee, Iran University of Medical Sciences, Tehran, Iran; Department of Physiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Ramezani
- Physiology Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Atousa Janzadeh
- Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Behnaz Rahimi
- Department of Physiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Farinaz Nasirinezhad
- Department of Physiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Physiology Research Center, Iran University of Medical Sciences, Tehran, Iran
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24
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Harper KM, Knapp DJ, Todd CA, Balan I, Aurelian L, Criswell HE, Breese GR. Phenotyping CCL2 Containing Central Amygdala Neurons Controlling Alcohol Withdrawal-Induced Anxiety. Front Cell Neurosci 2020; 14:580583. [PMID: 33192326 PMCID: PMC7531233 DOI: 10.3389/fncel.2020.580583] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 08/24/2020] [Indexed: 11/30/2022] Open
Abstract
Chemokines such as chemokine (C-C motif) ligand 2 (CCL2) play a role in several behaviors, including anxiety-like behavior, but whether neurons are an important source of CCL2 for behavior and how neuronal CCL2 may work to affect behavior are still debated. When a herpes simplex virus (HSV) vector was used to knockdown CCL2 mRNA in neurons of the central nucleus of the amygdala (CeA) in rats experiencing multiple withdrawals from low dose ethanol, anxiety-like behavior appeared in the social interaction task. To examine this finding further Fractalkine (CX3CL1), a chemokine that is often found to have an opposing function to CCL2 was measured in these rats. Both alcohol withdrawal and CCL2 knockdown increased the levels of the anti-inflammatory protein CX3CL1. The combination of alcohol withdrawal and CCL2 knockdown decreased CX3CL1 and may alter pro-inflammatory/anti-inflammatory balance, and thus highlights the potential importance of CCL2 and CCL2/CX3CL1 balance in anxiety. To find a mechanism by which neuronal chemokines like CCL2 could affect behavior, retrograde tracing with fluorescent nanobeads was done in two brain regions associated with anxiety the bed nucleus of the stria terminalis (BNST) and the ventral periaqueductal gray (VPAG). These studies identified CeA projection neurons to these brain regions that contain CCL2. To demonstrate that CCL2 can be transported via axons to downstream brain regions, the axonal transport blocker, colchicine, was given and 24 h later, the accumulation of CCL2 in CeA neuronal cell bodies was found. Finally, CCL2 in CeA neurons was localized to the synapse using confocal microscopy with enhanced resolution following deconvolution and electron microscopy, which along with the other evidence suggests that CCL2 may be transported down axons in CeA neurons and released from nerve terminals perhaps into brain regions like the BNST and VPAG to affect behaviors such as anxiety. These results suggest that neurons are an important target for chemokine research related to behavior.
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Affiliation(s)
- Kathryn M Harper
- Department of Psychiatry, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States.,Bowles Center for Alcohol Studies, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - Darin J Knapp
- Department of Psychiatry, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States.,Bowles Center for Alcohol Studies, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - Caroline A Todd
- Department of Psychiatry, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - Irina Balan
- Bowles Center for Alcohol Studies, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States.,Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Laure Aurelian
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, United States.,Stanford University School of Medicine, Stanford University, Stanford, CA, United States
| | - Hugh E Criswell
- Bowles Center for Alcohol Studies, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - George R Breese
- Department of Psychiatry, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States.,Bowles Center for Alcohol Studies, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States.,Department of Pharmacology, The University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
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25
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Rusinek K, Sołek P, Tabęcka-Łonczyńska A, Koziorowski M, Mytych J. Focus on the Role of Klotho Protein in Neuro-Immune Interactions in HT-22 Cells Upon LPS Stimulation. Cells 2020; 9:E1231. [PMID: 32429346 PMCID: PMC7290853 DOI: 10.3390/cells9051231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/07/2020] [Accepted: 05/15/2020] [Indexed: 12/12/2022] Open
Abstract
Neuroinflammation is defined as the activation of the brain's innate immune system in response to an inflammatory challenge and is considered to be a prominent feature of neurodegenerative diseases. The contribution of overactivated neuroglial cells to neuroinflammation and neurodegenerative disorders is well documented, however, the role of hippocampal neurons in the neuroinflammatory process remains fragmentary. In this study, we show for the first time, that klotho acts as a signal transducer between pro-survival and pro-apoptotic crosstalk mediated by ER stress in HT-22 hippocampal neuronal cells during LPS challenge. In control HT-22 cells, LPS treatment results in activation of the IRE1α-p38 MAPK pathway leading to increased secretion of anti-inflammatory IL-10, and thus, providing adaptation mechanism. On the other hand, in klotho-deficient HT-22 cells, LPS induces oxi-nitrosative stress and genomic instability associated with telomere dysfunctions leading to p53/p21-mediated cell cycle arrest and, in consequence, to ER stress, inflammation as well as of apoptotic cell death. Therefore, these results indicate that klotho serves as a part of the cellular defense mechanism engaged in the protection of neuronal cells against LPS-mediated neuroinflammation, emerging issues linked with neurodegenerative disorders.
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Affiliation(s)
| | | | | | | | - Jennifer Mytych
- Department of Animal Physiology and Reproduction, Institute of Biology and Biotechnology, Collegium Scientarium Naturalium, University of Rzeszow, Werynia 2, 36-100 Kolbuszowa, Poland; (K.R.); (P.S.); (A.T.-Ł.); (M.K.)
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26
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Manohar S, Russo FY, Seigel GM, Salvi R. Dynamic Changes in Synaptic Plasticity Genes in Ipsilateral and Contralateral Inferior Colliculus Following Unilateral Noise-induced Hearing Loss. Neuroscience 2020; 436:136-153. [PMID: 32278721 DOI: 10.1016/j.neuroscience.2020.04.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 03/07/2020] [Accepted: 04/03/2020] [Indexed: 12/27/2022]
Abstract
Unilateral noise-induced hearing loss reduces the input to the central auditory pathway disrupting the excitatory and inhibitory inputs to the inferior colliculus (IC), an important binaural processing center. Little is known about the compensatory synaptic changes that occur in the IC as a consequence of unilateral noise-induced hearing loss. To address this issue, Sprague-Dawley rats underwent unilateral noise exposure resulting in severe unilateral hearing loss. IC tissues from the contralateral and ipsilateral IC were evaluated for acute (2-d) and chronic (28-d) changes in the expression of 84 synaptic plasticity genes on a PCR array. Arc and Egr1 genes were further visualized by in situ hybridization to validate the PCR results. None of the genes were upregulated, but many were downregulated post-exposure. At 2-d post-exposure, more than 75% of the genes were significantly downregulated in the contralateral IC, while only two were downregulated in the ipsilateral IC. Many of the downregulated genes were related to long-term depression, long-term potentiation, cell adhesion, immediate early genes, neural receptors and postsynaptic density. At 28-d post-exposure, the gene expression pattern was reversed with more than 85% of genes in the ipsilateral IC now downregulated. Most genes previously downregulated in the contralateral IC 2-d post-exposure had recovered; less than 15% remained downregulated. These time-dependent, asymmetric changes in synaptic plasticity gene expression could shed new light on the perceptual deficits associated with unilateral hearing loss and the dynamic structural and functional changes that occur in the IC days and months following unilateral noise-induced hearing loss.
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Affiliation(s)
| | | | - Gail M Seigel
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY 14214, USA
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY 14214, USA.
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27
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Troubat R, Barone P, Leman S, Desmidt T, Cressant A, Atanasova B, Brizard B, El Hage W, Surget A, Belzung C, Camus V. Neuroinflammation and depression: A review. Eur J Neurosci 2020; 53:151-171. [DOI: 10.1111/ejn.14720] [Citation(s) in RCA: 225] [Impact Index Per Article: 56.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 02/20/2020] [Accepted: 03/03/2020] [Indexed: 02/06/2023]
Affiliation(s)
| | - Pascal Barone
- UMR 1253 iBrain Université de Tours Inserm Tours France
| | - Samuel Leman
- UMR 1253 iBrain Université de Tours Inserm Tours France
| | - Thomas Desmidt
- UMR 1253 iBrain Université de Tours Inserm Tours France
- CHRU de Tours Tours France
| | | | | | - Bruno Brizard
- UMR 1253 iBrain Université de Tours Inserm Tours France
| | - Wissam El Hage
- UMR 1253 iBrain Université de Tours Inserm Tours France
- CHRU de Tours Tours France
| | | | | | - Vincent Camus
- UMR 1253 iBrain Université de Tours Inserm Tours France
- CHRU de Tours Tours France
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28
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Medrano MP, Pisera-Fuster A, Bernabeu RO, Faillace MP. P2X7 and A 2A receptor endogenous activation protects against neuronal death caused by CoCl 2 -induced photoreceptor toxicity in the zebrafish retina. J Comp Neurol 2020; 528:2000-2020. [PMID: 31997350 DOI: 10.1002/cne.24869] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 01/09/2020] [Accepted: 01/22/2020] [Indexed: 12/20/2022]
Abstract
Injured retinas in mammals do not regenerate and heal with loss of function. The adult retina of zebrafish self-repairs after damage by activating cell-intrinsic mechanisms, which are regulated by extrinsic signal interactions. Among relevant regulatory extrinsic systems, purinergic signaling regulates progenitor proliferation during retinogenesis and regeneration and glia proliferation in proliferative retinopathies. ATP-activated P2X7 (P2RX7) and adenosine (P1R) receptors are involved in the progression of almost all retinopathies leading to blindness. Here, we examined P2RX7 and P1R participation in the retina regenerative response induced by photoreceptor damage caused by a specific dose of CoCl2 . First, we found that treatment of uninjured retinas with a potent agonist of P2RX7 (BzATP) provoked photoreceptor damage and mitotic activation of multipotent progenitors. In CoCl2 -injured retinas, blockade of endogenous extracellular ATP activity on P2RX7 caused further neurodegeneration, Müller cell gliosis, progenitor proliferation, and microglia reactivity. P2RX7 inhibition in injured retinas also increased the expression of lin28a and tnfα genes, which are related to multipotent progenitor proliferation. Levels of hif1α, vegf3r, and vegfaa mRNA were enhanced by blockade of P2RX7 immediately after injury, indicating hypoxic like damage and endothelial cell growth and proliferation. Complete depletion of extracellular nucleotides with an apyrase treatment strongly potentiated cell death and progenitor proliferation induced with CoCl2 . Blockade of adenosine P1 and A2A receptors (A2A R) had deleterious effects and deregulated normal timing for progenitor and precursor cell proliferation following photoreceptor damage. ATP via P2RX7 and adenosine via A2A R are survival extracellular signals key for retina regeneration in zebrafish.
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Affiliation(s)
- Matías P Medrano
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO-Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Antonella Pisera-Fuster
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO-Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Ramón O Bernabeu
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO-Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.,Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - María Paula Faillace
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO-Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.,Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
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29
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Pronin A, Pham D, An W, Dvoriantchikova G, Reshetnikova G, Qiao J, Kozhekbaeva Z, Reiser AE, Slepak VZ, Shestopalov VI. Inflammasome Activation Induces Pyroptosis in the Retina Exposed to Ocular Hypertension Injury. Front Mol Neurosci 2019; 12:36. [PMID: 30930743 PMCID: PMC6425693 DOI: 10.3389/fnmol.2019.00036] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 01/29/2019] [Indexed: 12/22/2022] Open
Abstract
Mechanical stress and hypoxia during episodes of ocular hypertension (OHT) trigger glial activation and neuroinflammation in the retina. Glial activation and release of pro-inflammatory cytokines TNFα and IL-1β, complement, and other danger factors was shown to facilitate injury and loss of retinal ganglion cells (RGCs) that send visual information to the brain. However, cellular events linking neuroinflammation and neurotoxicity remain poorly characterized. Several pro-inflammatory and danger signaling pathways, including P2X7 receptors and Pannexin1 (Panx1) channels, are known to activate inflammasome caspases that proteolytically activate gasdermin D channel-formation to export IL-1 cytokines and/or induce pyroptosis. In this work, we used molecular and genetic approaches to map and characterize inflammasome complexes and detect pyroptosis in the OHT-injured retina. Acute activation of distinct inflammasome complexes containing NLRP1, NLRP3 and Aim2 sensor proteins was detected in RGCs, retinal astrocytes and Muller glia of the OHT-challenged retina. Inflammasome-mediated activation of caspases-1 and release of mature IL-1β were detected within 6 h and peaked at 12–24 h after OHT injury. These coincided with the induction of pyroptotic pore protein gasdermin D in neurons and glia in the ganglion cell layer (GCL) and inner nuclear layer (INL). The OHT-induced release of cytokines and RGC death were significantly decreased in the retinas of Casp1−/−Casp4(11)del, Panx1−/− and in Wild-type (WT) mice treated with the Panx1 inhibitor probenecid. Our results showed a complex spatio-temporal pattern of innate immune responses in the retina. Furthermore, they indicate an active contribution of neuronal NLRP1/NLRP3 inflammasomes and the pro-pyroptotic gasdermin D pathway to pathophysiology of the OHT injury. These results support the feasibility of inflammasome modulation for neuroprotection in OHT-injured retinas.
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Affiliation(s)
- Alexey Pronin
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Dien Pham
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Weijun An
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Galina Dvoriantchikova
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Galina Reshetnikova
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Jianzhong Qiao
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Zhanna Kozhekbaeva
- Department of Medicine, The Division of Hematology and Oncology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Ashlyn E Reiser
- Geisinger Commonwealth School of Medicine, Scranton, PA, United States
| | - Vladlen Z Slepak
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Valery I Shestopalov
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States.,Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia.,Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL, United States
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30
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Pereiro X, Ruzafa N, Acera A, Fonollosa A, Rodriguez FD, Vecino E. Dexamethasone protects retinal ganglion cells but not Müller glia against hyperglycemia in vitro. PLoS One 2018; 13:e0207913. [PMID: 30475883 PMCID: PMC6258116 DOI: 10.1371/journal.pone.0207913] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 11/08/2018] [Indexed: 12/21/2022] Open
Abstract
Diabetic retinopathy (DR) is a common complication of diabetes, for which hyperglycemia is a major etiological factor. It is known that retinal glia (Müller cells) and retinal ganglion cells (RGCs) are affected by diabetes, and there is evidence that DR is associated with neural degeneration. Dexamethasone is a glucocorticoid used to treat many inflammatory and autoimmune conditions, including several eye diseases like DR. Thus, our goal was to study the effect of dexamethasone on the survival of RGCs and Müller glial cells isolated from rat retinas and maintained in vitro under hyperglycemic conditions. The behavior of primary RGC cell cultures, and of mixed RGC and Müller cell co-cultures, was studied in hyperglycemic conditions (30 mM glucose), both in the presence and absence of Dexamethasone (1 μM). RGC and Müller cell survival was evaluated, and the conditioned media of these cultures was collected to quantify the inflammatory cytokines secreted by these cells using a multiplex assay. The role of IL-1β, IL-6 and TNFα in RGC death was also evaluated by adding these cytokines to the co-cultures. RGC survival decreased significantly when these cells were grown in high glucose conditions, reaching 54% survival when they were grown alone and only 33% when co-cultured with Müller glia. The analysis of the cytokines in the conditioned media revealed an increase in IL-1β, IL-6 and TNFα under hyperglycemic conditions, which reverted to the basal concentration in co-cultures maintained in the presence of dexamethasone. Finally, when these cytokines were added to co-cultures they appeared to have a direct effect on RGC survival. Hence, these cytokines could be implicated in the death of RGCs when glucose concentrations increase and dexamethasone might protect RGCs from the cell death induced in these conditions.
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Affiliation(s)
- Xandra Pereiro
- Department of Cell Biology and Histology, University of Basque Country UPV/EHU, Leioa, Vizcaya, Spain
- * E-mail:
| | - Noelia Ruzafa
- Department of Cell Biology and Histology, University of Basque Country UPV/EHU, Leioa, Vizcaya, Spain
| | - Arantxa Acera
- Department of Cell Biology and Histology, University of Basque Country UPV/EHU, Leioa, Vizcaya, Spain
| | - Alex Fonollosa
- Servicio Oftalmología Hospital de Cruces, BioCruces, Barakaldo, Vizcaya, Spain
| | - F. David Rodriguez
- Department of Biochemistry and Molecular Biology, University of Salamanca, Salamanca, Spain
| | - Elena Vecino
- Department of Cell Biology and Histology, University of Basque Country UPV/EHU, Leioa, Vizcaya, Spain
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31
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Ventura ALM, Dos Santos-Rodrigues A, Mitchell CH, Faillace MP. Purinergic signaling in the retina: From development to disease. Brain Res Bull 2018; 151:92-108. [PMID: 30458250 DOI: 10.1016/j.brainresbull.2018.10.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/14/2018] [Accepted: 10/23/2018] [Indexed: 02/07/2023]
Abstract
Retinal injuries and diseases are major causes of human disability involving vision impairment by the progressive and permanent loss of retinal neurons. During development, assembly of this tissue entails a successive and overlapping, signal-regulated engagement of complex events that include proliferation of progenitors, neurogenesis, cell death, neurochemical differentiation and synaptogenesis. During retinal damage, several of these events are re-activated with both protective and detrimental consequences. Purines and pyrimidines, along with their metabolites are emerging as important molecules regulating both retinal development and the tissue's responses to damage. The present review provides an overview of the purinergic signaling in the developing and injured retina. Recent findings on the presence of vesicular and channel-mediated ATP release by retinal and retinal pigment epithelial cells, adenosine synthesis and release, expression of receptors and intracellular signaling pathways activated by purinergic signaling in retinal cells are reported. The pathways by which purinergic receptors modulate retinal cell proliferation, migration and death of retinal cells during development and injury are summarized. The contribution of nucleotides to the self-repair of the injured zebrafish retina is also discussed.
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Affiliation(s)
- Ana Lucia Marques Ventura
- Department of Neurobiology, Neuroscience Program, Fluminense Federal University, Niterói, RJ, Brazil.
| | | | - Claire H Mitchell
- Department of Anatomy and Cell Biology, Ophthalmology, and Physiology, University of Pennsylvania, Philadelphia, PA 19104, United States.
| | - Maria Paula Faillace
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO-Houssay), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina; Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
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32
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Medrano MP, Pisera Fuster A, Sanchis PA, Paez N, Bernabeu RO, Faillace MP. Characterization of proliferative, glial and angiogenic responses after a CoCl
2
‐induced injury of photoreceptor cells in the adult zebrafish retina. Eur J Neurosci 2018; 48:3019-3042. [DOI: 10.1111/ejn.14113] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 07/13/2018] [Accepted: 08/03/2018] [Indexed: 01/05/2023]
Affiliation(s)
- Matias Pedro Medrano
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO‐Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
| | - Antonella Pisera Fuster
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO‐Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
| | - Pablo Antonio Sanchis
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO‐Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
| | - Natalia Paez
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO‐Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
| | - Ramon Oscar Bernabeu
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO‐Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
- Departamento de FisiologíaFacultad de MedicinaUniversidad de Buenos Aires (UBA) Buenos Aires Argentina
| | - Maria Paula Faillace
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO‐Houssay) UBA y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
- Departamento de FisiologíaFacultad de MedicinaUniversidad de Buenos Aires (UBA) Buenos Aires Argentina
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33
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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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Lee PW, Xin MK, Pei W, Yang Y, Lovett-Racke AE. IL-3 Is a Marker of Encephalitogenic T Cells, but Not Essential for CNS Autoimmunity. Front Immunol 2018; 9:1255. [PMID: 29915594 PMCID: PMC5994593 DOI: 10.3389/fimmu.2018.01255] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/18/2018] [Indexed: 12/15/2022] Open
Abstract
Identifying molecules that are differentially expressed in encephalitogenic T cells is critical to the development of novel and specific therapies for multiple sclerosis (MS). In this study, IL-3 was identified as a molecule highly expressed in encephalitogenic Th1 and Th17 cells, but not in myelin-specific non-encephalitogenic Th1 and Th17 cells. However, B10.PL IL-3-deficient mice remained susceptible to experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. Furthermore, B10.PL myelin-specific T cell receptor transgenic IL-3-/- Th1 and Th17 cells were capable of transferring EAE to wild-type mice. Antibody neutralization of IL-3 produced by encephalitogenic Th1 and Th17 cells failed to alter their ability to transfer EAE. Thus, IL-3 is highly expressed in myelin-specific T cells capable of inducing EAE compared to activated, non-encephalitogenic myelin-specific T cells. However, loss of IL-3 in encephalitogenic T cells does not reduce their pathogenicity, indicating that IL-3 is a marker of encephalitogenic T cells, but not a critical element in their pathogenic capacity.
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Affiliation(s)
- Priscilla W. Lee
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States
| | - Matthew K. Xin
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States
| | - Wei Pei
- Department of Neurology, The Ohio State University, Columbus, OH, United States
| | - Yuhong Yang
- Department of Neurology, The Ohio State University, Columbus, OH, United States
| | - Amy E. Lovett-Racke
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States
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35
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Cook AD, Christensen AD, Tewari D, McMahon SB, Hamilton JA. Immune Cytokines and Their Receptors in Inflammatory Pain. Trends Immunol 2018; 39:240-255. [DOI: 10.1016/j.it.2017.12.003] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 11/28/2017] [Accepted: 12/13/2017] [Indexed: 01/23/2023]
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36
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Bucolo C, Platania CBM, Drago F, Bonfiglio V, Reibaldi M, Avitabile T, Uva M. Novel Therapeutics in Glaucoma Management. Curr Neuropharmacol 2018; 16:978-992. [PMID: 28925883 PMCID: PMC6120119 DOI: 10.2174/1570159x15666170915142727] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 06/26/2017] [Accepted: 09/03/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Glaucoma is a progressive optic neuropathy characterized by retinal ganglion cell death and alterations of visual field. Elevated intraocular pressure (IOP) is considered the main risk factor of glaucoma, even though other factors cannot be ruled out, such as epigenetic mechanisms. OBJECTIVE An overview of the ultimate promising experimental drugs to manage glaucoma has been provided. RESULTS In particular, we have focused on purinergic ligands, KATP channel activators, gases (nitric oxide, carbon monoxide and hydrogen sulfide), non-glucocorticoid steroidal compounds, neurotrophic factors, PI3K/Akt activators, citicoline, histone deacetylase inhibitors, cannabinoids, dopamine and serotonin receptors ligands, small interference RNA, and Rho kinase inhibitors. CONCLUSIONS The review has been also endowed of a brief chapter on last reports about potential neuroprotective benefits of anti-glaucoma drugs already present in the market.
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Affiliation(s)
- Claudio Bucolo
- Address correspondence to this author at the Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Via S. Sofia 97, 95123 Catania, Italy; Tel: +39 095 4781196;
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37
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Dong L, Hu Y, Zhou L, Cheng X. P2X7 receptor antagonist protects retinal ganglion cells by inhibiting microglial activation in a rat chronic ocular hypertension model. Mol Med Rep 2017; 17:2289-2296. [PMID: 29207073 PMCID: PMC5783460 DOI: 10.3892/mmr.2017.8137] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 11/09/2017] [Indexed: 12/31/2022] Open
Abstract
Microglial activation and the release of pro-inflammatory cytokines occur during early glaucoma. However, the exact mechanism underlying the initiation of the microglial activation process remains unclear. Thus, the present study investigated the potential role of a purine receptor subtype, the P2X purinoceptor 7 (P2X7) receptor, during microglial activation in the retinal tissues of a rat chronic ocular hypertension (COH) model. This was achieved by cauterizing 3 of the 4 episcleral veins. Microglial activation and caspase-1 upregulation were observed in COH rat retinas by immunohistochemical and western blotting techniques. Intravitreal injection of 2′,3′-O-(4-benzoylbenzoyl)-ATP (BzATP), a P2X7 receptor agonist, induced microglial activation in normal rat retinal tissues, which was alleviated by pretreatment with the P2X7 receptor antagonist, Brilliant Blue G (BBG). BBG further attenuated caspase-1 increment in COH rat retinal tissues. The data demonstrated that BBG reduced TUNEL-positive retinal ganglion cells in whole-mount retinal tissues with COH and normal retinal tissues following intravitreal injection with BzATP. One may conclude that the P2X7 receptor may be involved in microglial activation in the COH retina and could be considered a target for neuronal protection in glaucoma.
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Affiliation(s)
- Lingdan Dong
- Central Laboratory, First Affiliated Hospital of Yangtze University, Jingzhou, Hubei 434000, P.R. China
| | - Yanhong Hu
- Nursing Department, Medical School of Yangtze University, Jingzhou, Hubei 434000, P.R. China
| | - Long Zhou
- Department of Pathology, First Affiliated Hospital of Yangtze University, Jingzhou, Hubei 434000, P.R. China
| | - Xianglin Cheng
- Department of Neurology, First Affiliated Hospital of Yangtze University, Jingzhou, Hubei 434000, P.R. China
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Albalawi F, Lu W, Beckel JM, Lim JC, McCaughey SA, Mitchell CH. The P2X7 Receptor Primes IL-1β and the NLRP3 Inflammasome in Astrocytes Exposed to Mechanical Strain. Front Cell Neurosci 2017; 11:227. [PMID: 28848393 PMCID: PMC5550720 DOI: 10.3389/fncel.2017.00227] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 07/19/2017] [Indexed: 11/13/2022] Open
Abstract
Inflammatory responses play a key role in many neural pathologies, with localized signaling from the non-immune cells making critical contributions. The NLRP3 inflammasome is an important component of innate immune signaling and can link neural insult to chronic inflammation. The NLRP3 inflammasome requires two stages to contribute: priming and activation. The priming stage involves upregulation of inflammasome components while the activation stage results in the assembly and activation of the inflammasome complex. The priming step can be rate limiting and can connect insult to chronic inflammation, but our knowledge of the signals that regulate NLRP3 inflammasome priming in sterile inflammation is limited. This study examined the link between mechanical strain and inflammasome priming in neural systems. Transient non-ischemic elevation of intraocular pressure increased mRNA for inflammasome components IL-1β, NLRP3, ASC, and CASP1 in rat and mouse retinas. The elevation was greater 1 day after the insult, with the rise in IL-1β most pronounced. The P2X7 receptor was implicated in the mechanosensitive priming of IL-1β mRNA in vivo, as the antagonist Brilliant Blue G (BBG) blocked the increased expression, the agonist BzATP mimicked the pressure-dependent rise in IL-1β, and the rise was absent in P2X7 knockout mice. In vitro measurements from optic nerve head astrocytes demonstrated an increased expression of IL-1β following stretch or swelling. This increase in IL-1β was eliminated by degradation of extracellular ATP with apyrase, or by the block of pannexin hemichannels with carbenoxolone, probenecid, or 10panx1 peptide. The rise in IL-1β expression was also blocked by P2X7 receptor antagonists BBG, A839977 or A740003. The rise in IL-1β was prevented by blocking transcription factor NFκB with Bay 11-7082, while the swelling-dependent fall in NFκB inhibitor IκB-α was reduced by A839977 and in P2X7 knockout mice. In summary, mechanical trauma to the retina primed NLRP3 inflammasome components, but only if there was ATP release through pannexin hemichannels, and autostimulation of the P2X7 receptor. As the P2X7 receptor can also trigger stage two of inflammasome assembly and activation, the P2X7 receptor may have a central role in linking mechanical strain to neuroinflammation.
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Affiliation(s)
- Farraj Albalawi
- Department of Anatomy and Cell Biology, University of Pennsylvania, PhiladelphiaPA, United States.,Department of Orthodontics, University of Pennsylvania, PhiladelphiaPA, United States
| | - Wennan Lu
- Department of Anatomy and Cell Biology, University of Pennsylvania, PhiladelphiaPA, United States
| | - Jonathan M Beckel
- Department of Anatomy and Cell Biology, University of Pennsylvania, PhiladelphiaPA, United States.,Department of Pharmacology and Chemical Biology, Pittsburgh University, PittsburghPA, United States
| | - Jason C Lim
- Department of Anatomy and Cell Biology, University of Pennsylvania, PhiladelphiaPA, United States
| | - Stuart A McCaughey
- Department of Anatomy and Cell Biology, University of Pennsylvania, PhiladelphiaPA, United States
| | - Claire H Mitchell
- Department of Anatomy and Cell Biology, University of Pennsylvania, PhiladelphiaPA, United States.,Department of Ophthalmology, University of Pennsylvania, PhiladelphiaPA, United States.,Department of Physiology, University of Pennsylvania, PhiladelphiaPA, United States
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Lu W, Albalawi F, Beckel JM, Lim JC, Laties AM, Mitchell CH. The P2X7 receptor links mechanical strain to cytokine IL-6 up-regulation and release in neurons and astrocytes. J Neurochem 2017; 141:436-448. [PMID: 28244110 DOI: 10.1111/jnc.13998] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 01/11/2017] [Accepted: 02/09/2017] [Indexed: 12/15/2022]
Abstract
Mechanical strain in neural tissues can lead to the up-regulation and release of multiple cytokines including interleukin 6 (IL-6). In the retina, the mechanosensitive release of ATP can autostimulate P2X7 receptors on both retinal ganglion cell neurons and optic nerve head astrocytes. Here, we asked whether the purinergic signaling contributed to the IL-6 response to increased intraocular pressure (IOP) in vivo, and stretch or swelling in vitro. Rat and mouse eyes were exposed to non-ischemic elevations in IOP to 50-60 mmHg for 4 h. A PCR array was used to screen cytokine changes, with quantitative (q)PCR used to confirm mRNA elevations and immunoblots used for protein levels. P2X7 antagonist Brilliant Blue G (BBG) and agonist (4-benzoyl-benzoyl)-ATP (BzATP) were injected intravitreally. ELISA was used to quantify IL-6 release from optic nerve head astrocytes or retinal ganglion cells. Receptor identity was confirmed pharmacologically and in P2X7-/- mice, acute elevation of IOP altered retinal expression of multiple cytokine genes. Elevation of IL-6 was greatest, with expression of IL1rn, IL24, Tnf, Csf1, and Lif also increased more than twofold, while expression of Tnfsf11, Gdf9, and Tnfsf4 were reduced. qPCR confirmed the rise in IL-6 and extracellular ATP marker ENTPD1, but not pro-apoptotic genes. Intravitreal injection of P2X7 receptor antagonist BBG prevented the pressure-dependent rise in IL-6 mRNA and protein in the rat retina, while injection of P2X7 receptor agonist BzATP was sufficient to elevate IL-6 expression. IOP elevation increased IL-6 in wild-type but not P2X7R knockout mice. Application of mechanical strain to isolated optic nerve head astrocytes increased IL-6 levels. This response was mimicked by agonist BzATP, but blocked by antagonists BBG and A839977. Stretch or BzATP led to IL-6 release from both astrocytes and isolated retinal ganglion cells. The mechanosensitive up-regulation and release of cytokine IL-6 from the retina involves the P2X7 receptor, with both astrocytes and neurons contributing to the response.
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Affiliation(s)
- Wennan Lu
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Farraj Albalawi
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Orthodontics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jonathan M Beckel
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pennsylvania, USA
| | - Jason C Lim
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Alan M Laties
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Claire H Mitchell
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Physiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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