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Thakku Sivakumar D, Jain K, Alfehaid N, Wang Y, Teng X, Fischer W, Engel T. The Purinergic P2X7 Receptor as a Target for Adjunctive Treatment for Drug-Refractory Epilepsy. Int J Mol Sci 2024; 25:6894. [PMID: 39000004 PMCID: PMC11241490 DOI: 10.3390/ijms25136894] [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: 04/17/2024] [Revised: 06/06/2024] [Accepted: 06/17/2024] [Indexed: 07/14/2024] Open
Abstract
Epilepsy is one of the most common neurological diseases worldwide. Anti-seizure medications (ASMs) with anticonvulsants remain the mainstay of epilepsy treatment. Currently used ASMs are, however, ineffective to suppress seizures in about one third of all patients. Moreover, ASMs show no significant impact on the pathogenic mechanisms involved in epilepsy development or disease progression and may cause serious side-effects, highlighting the need for the identification of new drug targets for a more causal therapy. Compelling evidence has demonstrated a role for purinergic signalling, including the nucleotide adenosine 5'-triphosphate (ATP) during the generation of seizures and epilepsy. Consequently, drugs targeting specific ATP-gated purinergic receptors have been suggested as promising treatment options for epilepsy including the cationic P2X7 receptor (P27XR). P2X7R protein levels have been shown to be increased in the brain of experimental models of epilepsy and in the resected brain tissue of patients with epilepsy. Animal studies have provided evidence that P2X7R blocking can reduce the severity of acute seizures and the epileptic phenotype. The current review will provide a brief summary of recent key findings on P2X7R signalling during seizures and epilepsy focusing on the potential clinical use of treatments based on the P2X7R as an adjunctive therapeutic strategy for drug-refractory seizures and epilepsy.
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Affiliation(s)
- Divyeshz Thakku Sivakumar
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland
| | - Krishi Jain
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland
| | - Noura Alfehaid
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland
| | - Yitao Wang
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland
- International College of Pharmaceutical Innovation, Soochow University, Suzhou 215123, China
| | - Xinchen Teng
- International College of Pharmaceutical Innovation, Soochow University, Suzhou 215123, China
| | | | - Tobias Engel
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland
- FutureNeuro, Science Foundation Ireland Research Centre for Chronic and Rare Neurological Diseases, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland
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Zorina-Lichtenwalter K, Ase AR, Verma V, Parra AIM, Komarova S, Khadra A, Séguéla P, Diatchenko L. Characterization of Common Genetic Variants in P2RX7 and Their Contribution to Chronic Pain Conditions. THE JOURNAL OF PAIN 2024; 25:545-556. [PMID: 37742908 DOI: 10.1016/j.jpain.2023.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 08/22/2023] [Accepted: 09/19/2023] [Indexed: 09/26/2023]
Abstract
The adenosine triphosphate (ATP)-gated channel P2X7 is encoded by a gene enriched for common nonsynonymous variants. Many of these variants have functional cellular effects, and some have been implicated in chronic pain. In this study, we first systematically characterized all 17 common nonsynonymous variants using whole-cell patch clamp electrophysiology. Then, we analyzed these variants for statistical association with chronic pain phenotypes using both individual P2RX7 variants as predictors and cumulative allele counts of same-direction cellular effect in univariate models. Association and validation analyses were conducted in the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) cohort (N = 3260) and in the Complex Persistent Pain Conditions (CPPC) cohort (N = 900), respectively. Our results showed an association between allele A of rs7958311 and an increased risk of chronic pelvic pain, with convergent evidence for contribution to fibromyalgia and irritable bowel syndrome, confirmed in a meta-analysis. This allelic variant produced a unique cellular phenotype: a gain-of-function in channel opening, and a loss-of-function in pore opening. A computational study using a 12-state Markov model of ATP binding to the P2X7 receptor suggested that this cellular phenotype arises from an increased ATP binding affinity and an increased open channel conductance combined with a loss of sensitization. Cumulative allele count analysis did not provide additional insights. In conclusion, our results go beyond reproducing association for rs7958311 with chronic pain and suggest that its unique combination of gain-of-function in channel and loss-of-function in pore activity may explain why it is likely the only common P2RX7 variant with contribution to chronic pain. PERSPECTIVE: This study characterizes all common P2RX7 variants using cellular assays and statistical association analyses with chronic pain, with Markov state modeling of the most robustly associated variant.
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Affiliation(s)
- Katerina Zorina-Lichtenwalter
- Faculty of Dental Medicine and Oral Health Sciences, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Ariel R Ase
- Department of Neurology & Neurosurgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Montreal Neurological Institute/Hospital, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Vivek Verma
- Faculty of Dental Medicine and Oral Health Sciences, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Arturo I M Parra
- Faculty of Dental Medicine and Oral Health Sciences, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Svetlana Komarova
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Anmar Khadra
- Department of Physiology, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Philippe Séguéla
- Department of Neurology & Neurosurgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Montreal Neurological Institute/Hospital, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Luda Diatchenko
- Faculty of Dental Medicine and Oral Health Sciences, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, Department of Anesthesia, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada; Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
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Illes P, Ulrich H, Chen JF, Tang Y. Purinergic receptors in cognitive disturbances. Neurobiol Dis 2023; 185:106229. [PMID: 37453562 DOI: 10.1016/j.nbd.2023.106229] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 07/11/2023] [Accepted: 07/12/2023] [Indexed: 07/18/2023] Open
Abstract
Purinergic receptors (Rs) of the ATP/ADP, UTP/UDP (P2X, P2Y) and adenosine (A1, A2A)-sensitive classes broadly interfere with cognitive processes both under quasi normal and disease conditions. During neurodegenerative illnesses, high concentrations of ATP are released from the damaged neuronal and non-neuronal cells of the brain; then, this ATP is enzymatically degraded to adenosine. Thus, the primary injury in neurodegenerative diseases appears to be caused by various protein aggregates on which a superimposed damage mediated by especially P2X7 and A2AR activation develops; this can be efficiently prevented by small molecular antagonists in animal models of the above diseases, or are mitigated in the respective knockout mice. Dementia is a leading symptom in Alzheimer's disease (AD), and accompanies Parkinson's disease (PD) and Huntington's disease (HD), especially in the advanced states of these illnesses. Animal experimentation suggests that P2X7 and A2ARs are also involved in a number of psychiatric diseases, such as major depressive disorder (MDD), obsessive compulsive behavior, and attention deficit hyperactivity disorder. In conclusion, small molecular antagonists of purinergic receptors are expected to supply us in the future with pharmaceuticals which are able to combat in a range of neurological/psychiatric diseases the accompanying cognitive deterioration.
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Affiliation(s)
- Peter Illes
- School of Acupuncture and Tuina, Chengdu University of Traditonal Chinese Medicine, Chengdu 610075, China; Rudolf Boehm Institute for Pharmacology and Toxicology, University of Leipzig, 04107 Leipzig, Germany; International Joint Research Center for Purinergic Signaling, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China.
| | - Henning Ulrich
- International Joint Research Center for Purinergic Signaling, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China; Department of Biochemistry and Molecular Biology, Chemistry Institute, University of Sao Paulo (USP), Sao Paulo, Brazil
| | - Jiang-Fan Chen
- The Molecular Neuropharmacology Laboratory and the Eye-Brain Research Center, The State Key Laboratory of Ophthalmology, Optometry and Vision Science, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Whenzhou 325000, China
| | - Yong Tang
- School of Acupuncture and Tuina, Chengdu University of Traditonal Chinese Medicine, Chengdu 610075, China; International Joint Research Center for Purinergic Signaling, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China; Acupuncture and Chronobiology Key Laboratory of Sichuan Province, School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China.
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Budriesi P, Tintorelli R, Correa J, Villar ME, Marchal P, Giurfa M, Viola H. A behavioral tagging account of kinase contribution to memory formation after spaced aversive training. iScience 2023; 26:107278. [PMID: 37520708 PMCID: PMC10372744 DOI: 10.1016/j.isci.2023.107278] [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: 08/28/2022] [Revised: 09/14/2022] [Accepted: 06/30/2023] [Indexed: 08/01/2023] Open
Abstract
Long-term memory (LTM) can be induced by repeated spaced training trials. Using the weak inhibitory avoidance (wIA) task, we showed that one wIA session does not lead to a 24-h LTM, whereas two identical wIA sessions spaced by 15 min to 6 h induce a 24-h LTM. This LTM promotion depends both on hippocampal protein synthesis and the activity of several kinases. In agreement with the behavioral tagging (BT) hypothesis, our results suggest that the two training sessions induce transient learning tags and lead, via a cooperative effect, to the synthesis of plasticity-related proteins (PRPs) that become available and captured by the tag from the second session. Although ERKs1/2 are needed for PRPs synthesis and CaMKs are required for tag setting, PKA participates in both processes. We conclude that the BT mechanism accounts for the molecular constraints underlying the classic effect of spaced learning on LTM formation.
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Affiliation(s)
- Pablo Budriesi
- Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis” (IBCN), Facultad de Medicina, UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Ramiro Tintorelli
- Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis” (IBCN), Facultad de Medicina, UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Julieta Correa
- Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis” (IBCN), Facultad de Medicina, UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Maria Eugenia Villar
- Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis” (IBCN), Facultad de Medicina, UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
- Departamento de Biología y Geología, Física y Química Inorgánica, Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, Madrid, Spain
| | - Paul Marchal
- Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis” (IBCN), Facultad de Medicina, UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
- Poe Lab, Integrative Biology and Physiology department, University of California Los Angeles, Los Angeles, CA, USA
| | - Martin Giurfa
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse cedex 9, France
- Institut Universitaire de France (IUF), Paris, France
| | - Haydee Viola
- Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis” (IBCN), Facultad de Medicina, UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular “Dr. Héctor Maldonado” (FBMC), Facultad de Ciencias Exactas y Naturales, UBA, Ciudad Autónoma de Buenos Aires, Argentina
- Instituto Tecnológico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
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Dual Role of the P2X7 Receptor in Dendritic Outgrowth during Physiological and Pathological Brain Development. J Neurosci 2023; 43:1125-1142. [PMID: 36732073 PMCID: PMC9962779 DOI: 10.1523/jneurosci.0805-22.2022] [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: 04/22/2022] [Revised: 11/11/2022] [Accepted: 11/15/2022] [Indexed: 02/04/2023] Open
Abstract
At high levels, extracellular ATP operates as a "danger" molecule under pathologic conditions through purinergic receptors, including the ionotropic P2X7 receptor (P2X7R). Its endogenous activation is associated with neurodevelopmental disorders; however, its function during early embryonic stages remains largely unclear. Our objective was to determine the role of P2X7R in the regulation of neuronal outgrowth. For this purpose, we performed Sholl analysis of dendritic branches on primary hippocampal neurons and in acute hippocampal slices from WT mice and mice with genetic deficiency or pharmacological blockade of P2X7R. Because abnormal dendritic branching is a hallmark of certain neurodevelopmental disorders, such as schizophrenia, a model of maternal immune activation (MIA)-induced schizophrenia, was used for further morphologic investigations. Subsequently, we studied MIA-induced behavioral deficits in young adult mice females and males. Genetic deficiency or pharmacological blockade of P2X7R led to branching deficits under physiological conditions. Moreover, pathologic activation of the receptor led to deficits in dendritic outgrowth on primary neurons from WT mice but not those from P2X7R KO mice exposed to MIA. Likewise, only MIA-exposed WT mice displayed schizophrenia-like behavioral and cognitive deficits. Therefore, we conclude that P2X7R has different roles in the development of hippocampal dendritic arborization under physiological and pathologic conditions.SIGNIFICANCE STATEMENT Our main finding is a novel role for P2X7R in neuronal branching in the early stages of development under physiological conditions. We show how a decrease in the expression of P2X7R during brain development causes the receptor to play pathologic roles in adulthood. Moreover, we studied a neurodevelopmental model of schizophrenia and found that, at higher ATP concentrations, endogenous activation of P2X7R is necessary and sufficient for the development of positive and cognitive symptoms.
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Guerra Leal B, Barros-Barbosa A, Ferreirinha F, Chaves J, Rangel R, Santos A, Carvalho C, Martins-Ferreira R, Samões R, Freitas J, Lopes J, Ramalheira J, Lobo MG, Martins da Silva A, Costa PP, Correia-de-Sá P. Mesial Temporal Lobe Epilepsy (MTLE) Drug-Refractoriness Is Associated With P2X7 Receptors Overexpression in the Human Hippocampus and Temporal Neocortex and May Be Predicted by Low Circulating Levels of miR-22. Front Cell Neurosci 2022; 16:910662. [PMID: 35875355 PMCID: PMC9300956 DOI: 10.3389/fncel.2022.910662] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 06/07/2022] [Indexed: 11/13/2022] Open
Abstract
Objective: ATP-gated ionotropic P2X7 receptors (P2X7R) actively participate in epilepsy and other neurological disorders. Neocortical nerve terminals of patients with Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis (MTLE-HS) express higher P2X7R amounts. Overexpression of P2X7R bolsters ATP signals during seizures resulting in glial cell activation, cytokines production, and GABAergic rundown with unrestrained glutamatergic excitation. In a mouse model of status epilepticus, increased expression of P2X7R has been associated with the down-modulation of the non-coding micro RNA, miR-22. MiR levels are stable in biological fluids and normally reflect remote tissue production making them ideal disease biomarkers. Here, we compared P2X7R and miR-22 expression in epileptic brains and in the serum of patients with MTLE-HS, respectively.Methods: Quantitative RT-PCR was used to evaluate the expression of P2X7R in the hippocampus and anterior temporal lobe of 23 patients with MTLE-HS and 10 cadaveric controls. Confocal microscopy and Western blot analysis were performed to assess P2X7R protein amounts. MiR-22 expression was evaluated in cell-free sera of 40 MTLE-HS patients and 48 healthy controls.Results: Nerve terminals of the hippocampus and neocortical temporal lobe of MTLE-HS patients overexpress (p < 0.05) an 85 kDa P2X7R protein whereas the normally occurring 67 kDa receptor protein dominates in the brain of the cadaveric controls. Contrariwise, miR-22 serum levels are diminished (p < 0.001) in MTLE-HS patients compared to age-matched control blood donors, a situation that is more evident in patients requiring multiple (>3) anti-epileptic drug (AED) regimens.Conclusion: Data show that there is an inverse relationship between miR-22 serum levels and P2X7R expression in the hippocampus and neocortex of MTLE-HS patients, which implies that measuring serum miR-22 may be a clinical surrogate of P2X7R brain expression in the MTLE-HS. Moreover, the high area under the ROC curve (0.777; 95% CI 0.629–0.925; p = 0.001) suggests that low miR-22 serum levels may be a sensitive predictor of poor response to AEDs among MTLE-HS patients. Results also anticipate that targeting the miR-22/P2X7R axis may be a good strategy to develop newer AEDs.
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Affiliation(s)
- Bárbara Guerra Leal
- Unit for Multidisciplinary Research in Biomedicine (UMIB), Instituto de Ciências Biomédicas Abel Salazar—Universidade do Porto (ICBAS-UP), Porto, Portugal
- Immunogenetics Laboratory, Molecular Pathology and Immunology Department, ICBAS-UP, Porto, Portugal
- Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal
| | - Aurora Barros-Barbosa
- Laboratório de Farmacologia e Neurobiologia—Center for Drug Discovery and Innovative Medicines (MedInUP), ICBAS-UP, Porto, Portugal
| | - Fátima Ferreirinha
- Laboratório de Farmacologia e Neurobiologia—Center for Drug Discovery and Innovative Medicines (MedInUP), ICBAS-UP, Porto, Portugal
| | - João Chaves
- Unit for Multidisciplinary Research in Biomedicine (UMIB), Instituto de Ciências Biomédicas Abel Salazar—Universidade do Porto (ICBAS-UP), Porto, Portugal
- Serviço de Neurologia, Hospital de Santo António—Centro Hospitalar e Universitário do Porto (HSA-CHUP), Porto, Portugal
| | - Rui Rangel
- Serviço de Neurocirurgia, HSA-CHUP, Porto, Portugal
| | - Agostinho Santos
- Serviço de Patologia Forense, Instituto Nacional de Medicina Legal e Ciências Forenses—Delegação do Norte (INMLCF-DN), Porto, Portugal
| | - Cláudia Carvalho
- Immunogenetics Laboratory, Molecular Pathology and Immunology Department, ICBAS-UP, Porto, Portugal
| | - Ricardo Martins-Ferreira
- Unit for Multidisciplinary Research in Biomedicine (UMIB), Instituto de Ciências Biomédicas Abel Salazar—Universidade do Porto (ICBAS-UP), Porto, Portugal
- Immunogenetics Laboratory, Molecular Pathology and Immunology Department, ICBAS-UP, Porto, Portugal
| | - Raquel Samões
- Serviço de Neurologia, Hospital de Santo António—Centro Hospitalar e Universitário do Porto (HSA-CHUP), Porto, Portugal
| | - Joel Freitas
- Serviço de Neurofisiologia, HSA-CHUP, Porto, Portugal
| | - João Lopes
- Serviço de Neurofisiologia, HSA-CHUP, Porto, Portugal
| | | | - Maria Graça Lobo
- Laboratório de Farmacologia e Neurobiologia—Center for Drug Discovery and Innovative Medicines (MedInUP), ICBAS-UP, Porto, Portugal
| | - António Martins da Silva
- Unit for Multidisciplinary Research in Biomedicine (UMIB), Instituto de Ciências Biomédicas Abel Salazar—Universidade do Porto (ICBAS-UP), Porto, Portugal
- Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal
- Serviço de Neurofisiologia, HSA-CHUP, Porto, Portugal
| | - Paulo P. Costa
- Unit for Multidisciplinary Research in Biomedicine (UMIB), Instituto de Ciências Biomédicas Abel Salazar—Universidade do Porto (ICBAS-UP), Porto, Portugal
- Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal
- Departamento de Genética, Instituto Nacional de Saúde Dr. Ricardo Jorge, Porto, Portugal
| | - Paulo Correia-de-Sá
- Laboratório de Farmacologia e Neurobiologia—Center for Drug Discovery and Innovative Medicines (MedInUP), ICBAS-UP, Porto, Portugal
- *Correspondence: Paulo Correia-de-Sá orcid.org/0000-0002-6114-9189
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Huang H, Zheng S, Chen M, Xie L, Li Z, Guo M, Wang J, Lu M, Zhu X. The potential of the P2X7 receptor as a therapeutic target in a sub-chronic PCP-induced rodent model of schizophrenia. J Chem Neuroanat 2021; 116:101993. [PMID: 34147620 DOI: 10.1016/j.jchemneu.2021.101993] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 05/17/2021] [Accepted: 06/15/2021] [Indexed: 01/27/2023]
Abstract
OBJECTIVE We studied the role of the P2X7 receptor on cognitive dysfunction in a mouse model of schizophrenia. METHODS An adult mouse model was established by treatment with phencyclidine (PCP), an N-methyl-D-aspartate (NMDA) receptor antagonist. Young mice were divided into three groups: 1) the control (saline-injected) group; 2) experimental 5 mg/kg PCP-injected group; and 3) experimental 10 mg/kg PCP-injected group. The mice were subjected to the open-field and Morris water maze tests at 7 weeks. After intraperitoneal injection of the P2X7 receptor antagonist JNJ-47965567, the behaviour tests were performed again. Samples were taken after testing. The P2X7 receptor protein and mRNA expression levels were detected by immunohistochemistry, Western blotting and PCR. RESULTS This study revealed that the infant sub-chronic PCP mice model showed severe spatial learning and memory impairment in the Morris water maze and schizophrenia-like symptoms (hypermotor behaviour) in the open-field test. The P2X7 receptor protein was highly expressed in the sub-chronic PCP mouse model and more highly expressed in the hippocampus than the prefrontal lobe. After the P2X7 receptor was blocked with JNJ-47965567, P2X7 receptor protein and mRNA expression in the frontal lobe were significantly increased, and the spatial memory impairment and hypermotor behaviour induced by PCP were reversed. CONCLUSION PCP-induced cognitive impairment can be significantly improved by antagonizing the P2X7 receptor. Therefore, we believe that the P2X7 receptor plays an important role in the cognition of schizophrenic-like mice.
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Affiliation(s)
- Hui Huang
- Department of Neurosurgery, Second Affiliation Hospital, Nanchang University, Nanchang, Jiangxi, China; Institute of Neuroscience, Nanchang University, Nanchang, Jiangxi, China
| | - Suyue Zheng
- Department of Neurosurgery, First Affiliation Hospital, Nanchang University, Nanchang, Jiangxi, China
| | - Min Chen
- Department of Neurosurgery, Second Affiliation Hospital, Nanchang University, Nanchang, Jiangxi, China; Institute of Neuroscience, Nanchang University, Nanchang, Jiangxi, China
| | - Liyuan Xie
- Department of Neurosurgery, Second Affiliation Hospital, Nanchang University, Nanchang, Jiangxi, China; Institute of Neuroscience, Nanchang University, Nanchang, Jiangxi, China
| | - Ziyi Li
- Department of Neurosurgery, Second Affiliation Hospital, Nanchang University, Nanchang, Jiangxi, China; Institute of Neuroscience, Nanchang University, Nanchang, Jiangxi, China
| | - Min Guo
- Psychosomatic Medicine, Second Affiliation Hospital, Nanchang University, Nanchang, Jiangxi, China
| | - Jianhong Wang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences, Kunming Institute of Zoology, Kunming, Yunnan, China
| | - Mingwei Lu
- Department of Neurosurgery, Second Affiliation Hospital, Nanchang University, Nanchang, Jiangxi, China; Institute of Neuroscience, Nanchang University, Nanchang, Jiangxi, China.
| | - Xingen Zhu
- Department of Neurosurgery, Second Affiliation Hospital, Nanchang University, Nanchang, Jiangxi, China; Institute of Neuroscience, Nanchang University, Nanchang, Jiangxi, China.
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8
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Kimura LF, Novaes LS, Picolo G, Munhoz CD, Cheung CW, Camarini R. How environmental enrichment balances out neuroinflammation in chronic pain and comorbid depression and anxiety disorders. Br J Pharmacol 2021; 179:1640-1660. [PMID: 34076891 DOI: 10.1111/bph.15584] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 04/05/2021] [Accepted: 05/17/2021] [Indexed: 11/30/2022] Open
Abstract
Depression and anxiety commonly occur in chronic pain states and the coexistence of these diseases worsens outcomes for both disorders and may reduce treatment adherence and response. Despite the advances in the knowledge of chronic pain mechanisms, pharmacological treatment is still unsatisfactory. Research based on exposure to environmental enrichment is currently under investigation and seems to offer a promising low-cost strategy with no side effects. In this review, we discuss the role of inflammation as a major biological substrate and aetiological factor of chronic pain and depression/anxiety and report a collection of preclinical evidence of the effects and mechanisms of environmental enrichment. As microglia participates in the development of both conditions, we also discuss microglia as a potential target underlying the beneficial actions of environmental enrichment in chronic pain and comorbid depression/anxiety. We also discuss how alternative interventions under clinical guidelines, such as environmental enrichment, may improve treatment compliance and patient outcomes.
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Affiliation(s)
- Louise F Kimura
- Laboratory of Pain and Signaling, Butantan Institute, São Paulo, Brazil
| | - Leonardo S Novaes
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Gisele Picolo
- Laboratory of Pain and Signaling, Butantan Institute, São Paulo, Brazil
| | - Carolina D Munhoz
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Chi W Cheung
- Department of Anesthesiology, University of Hong Kong, Hong Kong
| | - Rosana Camarini
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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9
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Andrejew R, Oliveira-Giacomelli Á, Ribeiro DE, Glaser T, Arnaud-Sampaio VF, Lameu C, Ulrich H. The P2X7 Receptor: Central Hub of Brain Diseases. Front Mol Neurosci 2020; 13:124. [PMID: 32848594 PMCID: PMC7413029 DOI: 10.3389/fnmol.2020.00124] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/17/2020] [Indexed: 12/27/2022] Open
Abstract
The P2X7 receptor is a cation channel activated by high concentrations of adenosine triphosphate (ATP). Upon long-term activation, it complexes with membrane proteins forming a wide pore that leads to cell death and increased release of ATP into the extracellular milieu. The P2X7 receptor is widely expressed in the CNS, such as frontal cortex, hippocampus, amygdala and striatum, regions involved in neurodegenerative diseases and psychiatric disorders. Despite P2X7 receptor functions in glial cells have been extensively studied, the existence and roles of this receptor in neurons are still controversially discussed. Regardless, P2X7 receptors mediate several processes observed in neuropsychiatric disorders and brain tumors, such as activation of neuroinflammatory response, stimulation of glutamate release and neuroplasticity impairment. Moreover, P2X7 receptor gene polymorphisms have been associated to depression, and isoforms of P2X7 receptors are implicated in neuropsychiatric diseases. In view of that, the P2X7 receptor has been proposed to be a potential target for therapeutic intervention in brain diseases. This review discusses the molecular mechanisms underlying P2X7 receptor-mediated signaling in neurodegenerative diseases, psychiatric disorders, and brain tumors. In addition, it highlights the recent advances in the development of P2X7 receptor antagonists that are able of penetrating the central nervous system.
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Affiliation(s)
- Roberta Andrejew
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | - Deidiane Elisa Ribeiro
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Talita Glaser
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | - Claudiana Lameu
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Henning Ulrich
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
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10
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Illes P, Rubini P, Huang L, Tang Y. The P2X7 receptor: a new therapeutic target in Alzheimer’s disease. Expert Opin Ther Targets 2019; 23:165-176. [DOI: 10.1080/14728222.2019.1575811] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Peter Illes
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, Universität Leipzig, Leipzig, Germany
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China
| | - Patrizia Rubini
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China
| | - Lumei Huang
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China
| | - Yong Tang
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China
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11
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Purinergic system in psychiatric diseases. Mol Psychiatry 2018; 23:94-106. [PMID: 28948971 DOI: 10.1038/mp.2017.188] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 07/15/2017] [Accepted: 07/20/2017] [Indexed: 12/14/2022]
Abstract
Psychiatric disorders are debilitating diseases, affecting >80 million people worldwide. There are no causal cures for psychiatric disorders and available therapies only treat the symptoms. The etiology of psychiatric disorders is unknown, although it has been speculated to be a combination of environmental, stress and genetic factors. One of the neurotransmitter systems implicated in the biology of psychiatric disorders is the purinergic system. In this review, we performed a comprehensive search of the literature about the role and function of the purinergic system in the development and predisposition to psychiatric disorders, with a focus on depression, schizophrenia, bipolar disorder, autism, anxiety and attention deficit/hyperactivity disorder. We also describe how therapeutics used for psychiatric disorders act on the purinergic system.
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12
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Antipurinergic therapy for autism-An in-depth review. Mitochondrion 2017; 43:1-15. [PMID: 29253638 DOI: 10.1016/j.mito.2017.12.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 12/11/2017] [Accepted: 12/14/2017] [Indexed: 12/13/2022]
Abstract
Are the symptoms of autism caused by a treatable metabolic syndrome that traces to the abnormal persistence of a normal, alternative functional state of mitochondria? A small clinical trial published in 2017 suggests this is possible. Based on a new unifying theory of pathogenesis for autism called the cell danger response (CDR) hypothesis, this study of 10 boys, ages 5-14years, showed that all 5 boys who received antipurinergic therapy (APT) with a single intravenous dose of suramin experienced improvements in all the core symptoms of autism that lasted for 5-8weeks. Language, social interaction, restricted interests, and repetitive movements all improved. Two children who were non-verbal spoke their first sentences. None of these improvements were observed in the placebo group. Larger and longer studies are needed to confirm this promising discovery. This review introduces the concept of M2 (anti-inflammatory) and M1 (pro-inflammatory) mitochondria that are polarized along a functional continuum according to cell stress. The pathophysiology of the CDR, the complementary functions of M1 and M2 mitochondria, relevant gene-environment interactions, and the metabolic underpinnings of behavior are discussed as foundation stones for understanding the improvements in ASD behaviors produced by antipurinergic therapy in this small clinical trial.
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13
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Gölöncsér F, Baranyi M, Balázsfi D, Demeter K, Haller J, Freund TFF, Zelena D, Sperlágh B. Regulation of Hippocampal 5-HT Release by P2X7 Receptors in Response to Optogenetic Stimulation of Median Raphe Terminals of Mice. Front Mol Neurosci 2017; 10:325. [PMID: 29075178 PMCID: PMC5643475 DOI: 10.3389/fnmol.2017.00325] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 09/27/2017] [Indexed: 01/01/2023] Open
Abstract
Serotonergic and glutamatergic neurons of median raphe region (MRR) play a pivotal role in the modulation of affective and cognitive functions. These neurons synapse both onto themselves and remote cortical areas. P2X7 receptors (P2rx7) are ligand gated ion channels expressed by central presynaptic excitatory nerve terminals and involved in the regulation of neurotransmitter release. P2rx7s are implicated in various neuropsychiatric conditions such as schizophrenia and depression. Here we investigated whether 5-HT release released from the hippocampal terminals of MRR is subject to modulation by P2rx7s. To achieve this goal, an optogenetic approach was used to selectively activate subpopulation of serotonergic terminals derived from the MRR locally, and one of its target area, the hippocampus. Optogenetic activation of neurons in the MRR with 20 Hz was correlated with freezing and enhanced locomotor activity of freely moving mice and elevated extracellular levels of 5-HT, glutamate but not GABA in vivo. Similar optical stimulation (OS) significantly increased [3H]5-HT and [3H]glutamate release in acute MRR and hippocampal slices. We examined spatial and temporal patterns of [3H]5-HT release and the interaction between the serotonin and glutamate systems. Whilst [3H]5-HT release from MRR neurons was [Ca2+]o-dependent and sensitive to TTX, CNQX and DL-AP-5, release from hippocampal terminals was not affected by the latter drugs. Hippocampal [3H]5-HT released by electrical but not OS was subject to modulation by 5- HT1B/D receptors agonist sumatriptan (1 μM), whereas the selective 5-HT1A agonist buspirone (0.1 μM) was without effect. [3H]5-HT released by electrical and optical stimulation was decreased in mice genetically deficient in P2rx7s, and after perfusion with selective P2rx7 antagonists, JNJ-47965567 (0.1 μM), and AZ-10606120 (0.1 μM). Optical and electrical stimulation elevated the extracellular level of ATP. Our results demonstrate for the first time the modulation of 5-HT release from hippocampal MRR terminals by the endogenous activation of P2rx7s. P2rx7 mediated modulation of 5-HT release could contribute to various physiological and pathophysiological phenomena, related to hippocampal serotonergic transmission.
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Affiliation(s)
- Flóra Gölöncsér
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary.,János Szentágothai School of Neurosciences, Semmelweis University School of Ph.D. Studies, Budapest, Hungary
| | - Mária Baranyi
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Diána Balázsfi
- János Szentágothai School of Neurosciences, Semmelweis University School of Ph.D. Studies, Budapest, Hungary.,Laboratory of Stress and Behavior Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Kornél Demeter
- Unit of Behavioral Studies, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - József Haller
- Laboratory of Stress and Behavior Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary.,Unit of Behavioral Studies, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Tamás F F Freund
- Laboratory of Cerebral Cortex, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Dóra Zelena
- Laboratory of Stress and Behavior Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Beáta Sperlágh
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
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Domingos LB, Hott SC, Terzian ALB, Resstel LBM. P2X7 purinergic receptors participate in the expression and extinction processes of contextual fear conditioning memory in mice. Neuropharmacology 2017; 128:474-481. [PMID: 28802645 DOI: 10.1016/j.neuropharm.2017.08.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 07/27/2017] [Accepted: 08/08/2017] [Indexed: 12/21/2022]
Abstract
The purinergic system consists of two large receptor families - P2X and P2Y. Both are activated by adenosine triphosphate (ATP), although presenting different functions. These receptors are present in several brain regions, including those involved in emotion and stress-related behaviors. Hence, they seem to participate in fear- and anxiety-related responses. However, few studies have investigated the purinergic system in threatening situations, as observed in contextual fear conditioning (CFC). Therefore, this study investigated the involvement of purinergic receptors in the expression and extinction of aversive memories. C57Bl/6 background mice were submitted to the CFC protocol. Wildtype (WT) mice received i.p. injection of either a nonselective P2 receptor (P2R) antagonist, P178 (10 or 30 mg/kg); a selective P2X7 receptor (P2X7R) antagonist, A438079 (10 mg/kg); a selective P2Y1 receptor (P2Y1R) antagonist, MRS2179 (10 mg/kg); or vehicle 10 min prior to or immediately after the extinction session. Additionally, P2X7R KO mice were tested in the CFC protocol. After P2R antagonist treatment, contextual fear recall increased, while acquisition of extinction was impaired. Similar results were observed with the selective P2X7R antagonist, but not with the selective P2Y1R antagonist. Interestingly, P2X7R KO mice showed increased contextual fear recall, associated with impaired acquisition of extinction, in accordance with pharmacologic P2X7R antagonism. Our results suggest that specific pharmacological or genetic blockade of P2X7R promotes anxiogenic-like effects, along with deficits in extinction learning. Thus, these receptors could present an alternative treatment of stress-related psychiatric disorders.
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Affiliation(s)
- L B Domingos
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - S C Hott
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - A L B Terzian
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - L B M Resstel
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
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15
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Koványi B, Csölle C, Calovi S, Hanuska A, Kató E, Köles L, Bhattacharya A, Haller J, Sperlágh B. The role of P2X7 receptors in a rodent PCP-induced schizophrenia model. Sci Rep 2016; 6:36680. [PMID: 27824163 PMCID: PMC5099752 DOI: 10.1038/srep36680] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 10/18/2016] [Indexed: 02/07/2023] Open
Abstract
P2X7 receptors (P2X7Rs) are ligand-gated ion channels sensitive to extracellular ATP. Here we examined for the first time the role of P2X7R in an animal model of schizophrenia. Using the PCP induced schizophrenia model we show that both genetic deletion and pharmacological inhibition of P2X7Rs alleviate schizophrenia-like behavioral alterations. In P2rx7+/+ mice, PCP induced hyperlocomotion, stereotype behavior, ataxia and social withdrawal. In P2X7 receptor deficient mice (P2rx7−/−), the social interactions were increased, whereas the PCP induced hyperlocomotion and stereotype behavior were alleviated. The selective P2X7 receptor antagonist JNJ-47965567 partly replicated the effect of gene deficiency on PCP-induced behavioral changes and counteracted PCP-induced social withdrawal. We also show that PCP treatment upregulates and increases the functional responsiveness of P2X7Rs in the prefrontal cortex of young adult animals. The amplitude of NMDA evoked currents recorded from layer V pyramidal neurons of cortical slices were slightly decreased by both genetic deletion of P2rx7 and by JNJ-47965567. PCP induced alterations in mRNA expression encoding schizophrenia-related genes, such as NR2A, NR2B, neuregulin 1, NR1 and GABA α1 subunit were absent in the PFC of young adult P2rx7−/− animals. Our findings point to P2X7R as a potential therapeutic target in schizophrenia.
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Affiliation(s)
- Bence Koványi
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences (IEM HAS), H-1450 Budapest, Hungary.,János Szentágothai School of Neurosciences, Semmelweis University School of PhD Studies, Budapest, Hungary
| | - Cecilia Csölle
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences (IEM HAS), H-1450 Budapest, Hungary
| | - Stefano Calovi
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences (IEM HAS), H-1450 Budapest, Hungary
| | - Adrienn Hanuska
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, H-1089 Budapest, Hungary
| | - Erzsébet Kató
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, H-1089 Budapest, Hungary
| | - László Köles
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, H-1089 Budapest, Hungary
| | | | - József Haller
- Department of Behavioral Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences (IEM HAS), H-1450, Budapest, Hungary
| | - Beáta Sperlágh
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences (IEM HAS), H-1450 Budapest, Hungary
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16
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ATPergic signalling during seizures and epilepsy. Neuropharmacology 2015; 104:140-53. [PMID: 26549853 DOI: 10.1016/j.neuropharm.2015.11.001] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/01/2015] [Accepted: 11/02/2015] [Indexed: 10/22/2022]
Abstract
Much progress has been made over the last few decades in the identification of new anti-epileptic drugs (AEDs). However, 30% of epilepsy patients suffer poor seizure control. This underscores the need to identify alternative druggable neurotransmitter systems and drugs with novel mechanisms of action. An emerging concept is that seizure generation involves a complex interplay between neurons and glial cells at the tripartite synapse and neuroinflammation has been proposed as one of the main drivers of epileptogenesis. The ATP-gated purinergic receptor family is expressed throughout the brain and is functional on neurons and glial cells. ATP is released in high amounts into the extracellular space after increased neuronal activity and during chronic inflammation and cell death to act as a neuro- and gliotransmitter. Emerging work shows pharmacological targeting of ATP-gated purinergic P2 receptors can potently modulate seizure generation, inflammatory processes and seizure-induced brain damage. To date, work showing the functional contribution of P2 receptors has been mainly performed in animal models of acute seizures, in particular, by targeting the ionotropic P2X7 receptor subtype. Other ionotropic P2X and metabotropic P2Y receptor family members have also been implicated in pathological processes following seizures such as the P2X4 receptor and the P2Y12 receptor. However, during epilepsy, the characterization of P2 receptors was mostly restricted to the study of expressional changes of the different receptor subtypes. This review summarizes the work to date on ATP-mediated signalling during seizures and the functional impact of targeting the ATP-gated purinergic receptors on seizures and seizure-induced pathology. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'.
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17
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Doorn KJ, Brevé JJP, Drukarch B, Boddeke HW, Huitinga I, Lucassen PJ, van Dam AM. Brain region-specific gene expression profiles in freshly isolated rat microglia. Front Cell Neurosci 2015; 9:84. [PMID: 25814934 PMCID: PMC4357261 DOI: 10.3389/fncel.2015.00084] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/23/2015] [Indexed: 12/30/2022] Open
Abstract
Microglia are important cells in the brain that can acquire different morphological and functional phenotypes dependent on the local situation they encounter. Knowledge on the region-specific gene signature of microglia may hold valuable clues for microglial functioning in health and disease, e.g., Parkinson's disease (PD) in which microglial phenotypes differ between affected brain regions. Therefore, we here investigated whether regional differences exist in gene expression profiles of microglia that are isolated from healthy rat brain regions relevant for PD. We used an optimized isolation protocol based on a rapid isolation of microglia from discrete rat gray matter regions using density gradients and fluorescent-activated cell sorting. Application of the present protocol followed by gene expression analysis enabled us to identify subtle differences in region-specific microglial expression profiles and show that the genetic profile of microglia already differs between different brain regions when studied under control conditions. As such, these novel findings imply that brain region-specific microglial gene expression profiles exist that may contribute to the region-specific differences in microglia responsivity during disease conditions, such as seen in, e.g., PD.
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Affiliation(s)
- Karlijn J Doorn
- Department Structural and Functional Plasticity of the Nervous System, Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam Amsterdam, Netherlands ; Neuroscience Campus Amsterdam, Department Anatomy and Neurosciences, VU University Medical Center Amsterdam, Netherlands
| | - John J P Brevé
- Neuroscience Campus Amsterdam, Department Anatomy and Neurosciences, VU University Medical Center Amsterdam, Netherlands
| | - Benjamin Drukarch
- Neuroscience Campus Amsterdam, Department Anatomy and Neurosciences, VU University Medical Center Amsterdam, Netherlands
| | - Hendrikus W Boddeke
- Section Medical Physiology, Department of Neuroscience, University Medical Centre Groningen Groningen, Netherlands
| | - Inge Huitinga
- Neuroimmunology Group, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences Amsterdam, Netherlands
| | - Paul J Lucassen
- Department Structural and Functional Plasticity of the Nervous System, Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam Amsterdam, Netherlands
| | - Anne-Marie van Dam
- Department Structural and Functional Plasticity of the Nervous System, Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam Amsterdam, Netherlands
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