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Tang H, Wei W, Luo Y, Lu X, Chen J, Yang S, Wu F, Zhou H, Ma W, Yang X. P2X7 receptors: a bibliometric review from 2002 to 2023. Purinergic Signal 2024:10.1007/s11302-024-09996-9. [PMID: 38421486 DOI: 10.1007/s11302-024-09996-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 02/21/2024] [Indexed: 03/02/2024] Open
Abstract
For many years, there has been ongoing research on the P2X7 receptor (P2X7R). A comprehensive, systematic, and objective evaluation of the scientific output and status of P2X7R will be instrumental in guiding future research directions. This study aims to present the status and trends of P2X7R research from 2002 to 2023. Publications related to P2X7R were retrieved from the Web of Science Core Collection database. Quantitative analysis and visualization tools were Microsoft Excel, VOSviewer, and CiteSpace software. The analysis content included publication trends, literature co-citation, and keywords. 3282 records were included in total, with the majority of papers published within the last 10 years. Based on literature co-citation and keyword analysis, neuroinflammation, neuropathic pain, gastrointestinal diseases, tumor microenvironment, rheumatoid arthritis, age-related macular degeneration, and P2X7R antagonists were considered to be the hotspots and frontiers of P2X7R research. Researchers will get a more intuitive understanding of the status and trends of P2X7R research from this study.
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Affiliation(s)
- Haiting Tang
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Wei Wei
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Yu Luo
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Xiaoqing Lu
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Jun Chen
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Shenqiao Yang
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Fei Wu
- School of Foreign Languages, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Haiyan Zhou
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Wenbin Ma
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Xin Yang
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
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2
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Yu C, Deng XJ, Xu D. Microglia in epilepsy. Neurobiol Dis 2023; 185:106249. [PMID: 37536386 DOI: 10.1016/j.nbd.2023.106249] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/07/2023] [Accepted: 07/31/2023] [Indexed: 08/05/2023] Open
Abstract
Epilepsy is one of most common chronic neurological disorders, and the antiseizure medications developed by targeting neurocentric mechanisms have not effectively reduced the proportion of patients with drug-resistant epilepsy. Further exploration of the cellular or molecular mechanism of epilepsy is expected to provide new options for treatment. Recently, more and more researches focus on brain network components other than neurons, among which microglia have attracted much attention for their diverse biological functions. As the resident immune cells of the central nervous system, microglia have highly plastic transcription, morphology and functional characteristics, which can change dynamically in a context-dependent manner during the progression of epilepsy. In the pathogenesis of epilepsy, highly reactive microglia interact with other components in the epileptogenic network by performing crucial functions such as secretion of soluble factors and phagocytosis, thus continuously reshaping the landscape of the epileptic brain microenvironment. Indeed, microglia appear to be both pro-epileptic and anti-epileptic under the different spatiotemporal contexts of disease, rendering interventions targeting microglia biologically complex and challenging. This comprehensive review critically summarizes the pathophysiological role of microglia in epileptic brain homeostasis alterations and explores potential therapeutic or modulatory targets for epilepsy targeting microglia.
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Affiliation(s)
- Cheng Yu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China
| | - Xue-Jun Deng
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China
| | - Da Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China.
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3
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The P2X7 Receptor as a Mechanistic Biomarker for Epilepsy. Int J Mol Sci 2023; 24:ijms24065410. [PMID: 36982485 PMCID: PMC10049244 DOI: 10.3390/ijms24065410] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/03/2023] [Accepted: 03/07/2023] [Indexed: 03/14/2023] Open
Abstract
Epilepsy, characterized by recurrent spontaneous seizures, is a heterogeneous group of brain diseases affecting over 70 million people worldwide. Major challenges in the management of epilepsy include its diagnosis and treatment. To date, video electroencephalogram (EEG) monitoring is the gold-standard diagnostic method, with no molecular biomarker in routine clinical use. Moreover, treatment based on anti-seizure medications (ASMs) remains ineffective in 30% of patients, and, even if seizure-suppressive, lacks disease-modifying potential. Current epilepsy research is, therefore, mainly focussed on the identification of new drugs with a different mechanism of action effective in patients not responding to current ASMs. The vast heterogeneity of epilepsy syndromes, including differences in underlying pathology, comorbidities and disease progression, represents, however, a particular challenge in drug discovery. Optimal treatment most likely requires the identification of new drug targets combined with diagnostic methods to identify patients in need of a specific treatment. Purinergic signalling via extracellularly released ATP is increasingly recognized to contribute to brain hyperexcitability and, consequently, drugs targeting this signalling system have been proposed as a new therapeutic strategy for epilepsy. Among the purinergic ATP receptors, the P2X7 receptor (P2X7R) has attracted particular attention as a novel target for epilepsy treatment, with P2X7Rs contributing to unresponsiveness to ASMs and drugs targeting the P2X7R modulating acute seizure severity and suppressing seizures during epilepsy. In addition, P2X7R expression has been reported to be altered in the brain and circulation in experimental models of epilepsy and patients, making it both a potential therapeutic and diagnostic target. The present review provides an update on the newest findings regarding P2X7R-based treatments for epilepsy and discusses the potential of P2X7R as a mechanistic biomarker.
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Vezzani A, Di Sapia R, Kebede V, Balosso S, Ravizza T. Neuroimmunology of status epilepticus. Epilepsy Behav 2023; 140:109095. [PMID: 36753859 DOI: 10.1016/j.yebeh.2023.109095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 01/14/2023] [Indexed: 02/09/2023]
Abstract
Status epilepticus (SE) is a very heterogeneous clinical condition often refractory to available treatment options. Evidence in animal models shows that neuroinflammation arises in the brain during SE due to the activation of innate immune mechanisms in brain parenchyma cells. Intervention studies in animal models support the involvement of neuroinflammation in SE onset, duration, and severity, refractoriness to treatments, and long-term neurological consequences. Clinical evidence shows that neuroinflammation occurs in patients with SE of diverse etiologies likely representing a common phenomenon, thus broadening the involvement of the immune system beyond the infective and autoimmune etiologies. There is urgent need for novel therapies for refractory SE that rely upon a better understanding of the basic mechanisms underlying this clinical condition. Preclinical and clinical evidence encourage consideration of specific anti-inflammatory treatments for controlling SE and its consequences in patients.
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Affiliation(s)
- Annamaria Vezzani
- Department of Acute Brain Injury, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Italy.
| | - Rossella Di Sapia
- Department of Acute Brain Injury, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Italy
| | - Valentina Kebede
- Department of Acute Brain Injury, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Italy
| | - Silvia Balosso
- Department of Acute Brain Injury, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Italy
| | - Teresa Ravizza
- Department of Acute Brain Injury, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Italy
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Beamer E, Kuchukulla M, Boison D, Engel T. ATP and adenosine-Two players in the control of seizures and epilepsy development. Prog Neurobiol 2021; 204:102105. [PMID: 34144123 DOI: 10.1016/j.pneurobio.2021.102105] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/07/2021] [Accepted: 06/09/2021] [Indexed: 02/08/2023]
Abstract
Despite continuous advances in understanding the underlying pathogenesis of hyperexcitable networks and lowered seizure thresholds, the treatment of epilepsy remains a clinical challenge. Over one third of patients remain resistant to current pharmacological interventions. Moreover, even when effective in suppressing seizures, current medications are merely symptomatic without significantly altering the course of the disease. Much effort is therefore invested in identifying new treatments with novel mechanisms of action, effective in drug-refractory epilepsy patients, and with the potential to modify disease progression. Compelling evidence has demonstrated that the purines, ATP and adenosine, are key mediators of the epileptogenic process. Extracellular ATP concentrations increase dramatically under pathological conditions, where it functions as a ligand at a host of purinergic receptors. ATP, however, also forms a substrate pool for the production of adenosine, via the action of an array of extracellular ATP degrading enzymes. ATP and adenosine have assumed largely opposite roles in coupling neuronal excitability to energy homeostasis in the brain. This review integrates and critically discusses novel findings regarding how ATP and adenosine control seizures and the development of epilepsy. This includes purine receptor P1 and P2-dependent mechanisms, release and reuptake mechanisms, extracellular and intracellular purine metabolism, and emerging receptor-independent effects of purines. Finally, possible purine-based therapeutic strategies for seizure suppression and disease modification are discussed.
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Affiliation(s)
- Edward Beamer
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin D02 YN77, Ireland; Centre for Bioscience, Manchester Metropolitan University, John Dalton Building, All Saints Campus, Manchester M15 6BH, UK
| | - Manvitha Kuchukulla
- Department of Neurosurgery, Robert Wood Johnson & New Jersey Medical Schools, Rutgers University, Piscataway, NJ 08854, USA
| | - Detlev Boison
- Department of Neurosurgery, Robert Wood Johnson & New Jersey Medical Schools, Rutgers University, Piscataway, NJ 08854, USA.
| | - Tobias Engel
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin D02 YN77, 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, Dublin D02 YN77, Ireland.
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6
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Chow CK, Luk HM, Wong SN. KCNQ2 Encephalopathy and Responsiveness to Pyridoxal-5'-Phosphate. J Pediatr Genet 2020; 12:90-94. [PMID: 36684546 PMCID: PMC9848766 DOI: 10.1055/s-0040-1721384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/25/2020] [Indexed: 01/25/2023]
Abstract
KCNQ2 mutations encompass a wide range of phenotypes, ranging from benign familial neonatal seizure to a clinical spectrum of early-onset epileptic encephalopathy that occurs in the early neonatal period. We report an infant with KCNQ2 encephalopathy presenting as neonatal seizure, initially controlled by two anticonvulsants. Electroencephalogram (EEG) showed repetitive multifocal epileptiform discharges, which remained similar after administration of intravenous pyridoxine injection. Seizure recurred at the age of 3 months preceded by an episode of minor viral infection, which occurred multiple times per day. No significant change in seizure frequency was observed after 5-day oral pyridoxine trial, but subsequently, there was dramatic seizure improvement with oral pyridoxal-5'-phosphate (PLP). We hope to alert clinicians that in patients with neonatal epileptic encephalopathy, particularly with known KCNQ2 mutations, intravenous injection of pyridoxine (preferably with EEG monitoring), followed by both oral trial of pyridoxine and PLP should be considered. KCNQ2 mutations should also be considered in vitamin B6-responsive patients.
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Affiliation(s)
- Chit Kwong Chow
- Department of Paediatrics and Adolescent Medicine, United Christian Hospital, HKSAR, Hong Kong,Address for correspondence Chit Kwong Chow, MBBS (HK), FHKC (Paed), FHKAM (Paediatrics) Department of Paediatrics and Adolescent Medicine, United Christian Hospital130 Hip Wo Street, Kwun Tong, Kowloon, HKSARHong Kong
| | - Ho Ming Luk
- Clinical Genetic Service, Department of Health, HKSAR, Hong Kong
| | - Suet Na Wong
- Department of Paediatrics and Adolescent Medicine, Hong Kong Children's Hospital, HKSAR, Hong Kong
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7
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Conte G, Nguyen NT, Alves M, de Diego-Garcia L, Kenny A, Nicke A, Henshall DC, Jimenez-Mateos EM, Engel T. P2X7 Receptor-Dependent microRNA Expression Profile in the Brain Following Status Epilepticus in Mice. Front Mol Neurosci 2020; 13:127. [PMID: 32982684 PMCID: PMC7485385 DOI: 10.3389/fnmol.2020.00127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/26/2020] [Indexed: 12/17/2022] Open
Abstract
The ionotropic ATP-gated P2X7 receptor is an important contributor to inflammatory signaling cascades via the release of Interleukin-1β, as well as having roles in cell death, neuronal plasticity and the release of neurotransmitters. Accordingly, there is interest in targeting the P2X7 receptor for the treatment of epilepsy. However, the signaling pathways downstream of P2X7 receptor activation remain incompletely understood. Notably, recent studies showed that P2X7 receptor expression is controlled, in part, by microRNAs (miRNAs). Here, we explored P2X7 receptor-dependent microRNA expression by comparing microRNA expression profiles of wild-type (wt) and P2X7 receptor knockout mice before and after status epilepticus. Genome-wide microRNA profiling was performed using hippocampi from wt and P2X7 receptor knockout mice following status epilepticus induced by intra-amygdala kainic acid. This revealed that the genetic deletion of the P2X7 receptor results in distinct patterns of microRNA expression. Specifically, we found that in vehicle-injected control mice, the lack of the P2X7 receptor resulted in the up-regulation of 50 microRNAs and down-regulation of 35 microRNAs. Post-status epilepticus, P2X7 receptor deficiency led to the up-regulation of 44 microRNAs while 13 microRNAs were down-regulated. Moreover, there was only limited overlap among identified P2X7 receptor-dependent microRNAs between control conditions and post-status epilepticus, suggesting that the P2X7 receptor regulates the expression of different microRNAs during normal physiology and pathology. Bioinformatic analysis revealed that genes targeted by P2X7 receptor-dependent microRNAs were particularly overrepresented in pathways involved in intracellular signaling, inflammation, and cell death; processes that have been repeatedly associated with P2X7 receptor activation. Moreover, whereas genes involved in signaling pathways and inflammation were common among up- and down-regulated P2X7 receptor-dependent microRNAs during physiological and pathological conditions, genes associated with cell death seemed to be restricted to up-regulated microRNAs during both physiological conditions and post-status epilepticus. Taken together, our results demonstrate that the P2X7 receptor impacts on the expression profile of microRNAs in the brain, thereby possibly contributing to both the maintenance of normal cellular homeostasis and pathological processes.
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Affiliation(s)
- Giorgia Conte
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland
| | - Ngoc T Nguyen
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland.,FutureNeuro, Science Foundation Ireland (SFI) Research Centre for Chronic and Rare Neurological Diseases, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland
| | - Mariana Alves
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland
| | - Laura de Diego-Garcia
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland
| | - Aidan Kenny
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland
| | - Annette Nicke
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - David C Henshall
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland.,FutureNeuro, Science Foundation Ireland (SFI) Research Centre for Chronic and Rare Neurological Diseases, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland
| | - Eva M Jimenez-Mateos
- Discipline of Physiology, School of Medicine, Trinity College Ireland, The University of Dublin, Dublin, Ireland
| | - Tobias Engel
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland.,FutureNeuro, Science Foundation Ireland (SFI) Research Centre for Chronic and Rare Neurological Diseases, Royal College of Surgeons in Ireland (RCSI), Dublin, Ireland
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8
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Ramos AB, Cruz RA, Villemarette-Pittman NR, Olejniczak PW, Mader EC. Dexamethasone as Abortive Treatment for Refractory Seizures or Status Epilepticus in the Inpatient Setting. J Investig Med High Impact Case Rep 2020; 7:2324709619848816. [PMID: 31104535 PMCID: PMC6537247 DOI: 10.1177/2324709619848816] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Refractory seizures or status epilepticus (RS/SE) continues to be a challenge in
the inpatient setting. Failure to abort a seizure with antiepileptic drugs
(AEDs) may lead to intubation and treatment with general anesthesia exposing
patients to complications, extending hospitalization, and increasing the cost of
care. Studies have shown a key role of inflammatory mediators in seizure
generation and termination. We describe 4 patients with RS/SE that was aborted
when dexamethasone was added to conventional AEDs: a 61-year-old female with
temporal lobe epilepsy who presented with delirium, nonconvulsive status
epilepticus, and oculomyoclonic status; a 56-year-old female with history of
traumatic left frontal lobe hemorrhage who developed right face and hand
epilepsia partialis continua followed by refractory focal clonic seizures; a
51-year-old male with history of traumatic intracranial hemorrhage who exhibited
left-sided epilepsia partialis continua; and a 75-year-old female with history
of breast cancer who manifested nonconvulsive status epilepticus and refractory
focal clonic seizures. All patients continued experiencing RS/SE despite first-
and second-line therapy, and one patient continued to experience RS/SE despite
third-line therapy. Failure to abort RS/SE with conventional therapy motivated
us to administer intravenous dexamethasone. A 10-mg load was given (except in
one patient) followed by 4.0- 5.2 mg q6h. All clinical and electrographic
seizures stopped 3-4 days after starting dexamethasone. When dexamethasone was
discontinued 1-3 days after seizures stopped, all patients remained seizure-free
on 2-3 AEDs. The cessation of RS/SE when dexamethasone was added to conventional
antiseizure therapy suggests that inflammatory processes are involved in the
pathogenesis of RS/SE.
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Affiliation(s)
- Alexander B Ramos
- 1 Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Roberto A Cruz
- 1 Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | | | - Piotr W Olejniczak
- 1 Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Edward C Mader
- 1 Louisiana State University Health Sciences Center, New Orleans, LA, USA
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Wang M, Deng X, Xie Y, Chen Y. Astaxanthin Attenuates Neuroinflammation in Status Epilepticus Rats by Regulating the ATP-P2X7R Signal. DRUG DESIGN DEVELOPMENT AND THERAPY 2020; 14:1651-1662. [PMID: 32431490 PMCID: PMC7201036 DOI: 10.2147/dddt.s249162] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/09/2020] [Indexed: 12/26/2022]
Abstract
Background As a life-threatening neurological emergency, status epilepticus (SE) is often refractory to available treatment. Current studies have shown a causal role of neuroinflammation in patients with lower seizure thresholds and driving seizures. The ATP-gated purinergic P2X7 receptor (P2X7R) is mainly expressed on the microglia, which function as gatekeepers of inflammation. Although emerging evidence has demonstrated significant anti-inflammatory effects of astaxanthin (AST) in SE, the associated mechanism remains unclear. Therefore, this study aimed to clarify the effects of AST on P2X7R-related inflammation in SE. Methods SE was induced in rats using lithium–pilocarpine, and AST was administered 1 h after SE induction. Rat microglia were treated with lipopolysaccharide (LPS), AST, ATP, 2,3-O-4-benzoyl-4-benzoyl-ATP (BzATP) and oxidized ATP (oxATP). The Morris water maze, immunohistochemistry, and Nissl staining were performed in rats. Expressions of P2X7R and inflammatory cytokines (such as cycloxygenase-2 (Cox-2), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α)) were detected using real-time polymerase chain reaction (RT-PCR) and Western blot (WB) both in rats and microglia. ATP concentration in the microglia was evaluated using ELISA. Results The AST alleviated hippocampal injury and improved cognitive dysfunction induced by SE. AST also effectively inhibited inflammation and downregulated P2X7R expression in both rat brain and microglia. The results also showed that AST reduced the extracellular ATP levels and that P2X7R expression could be increased by extracellular ATP. In addition, BzATP upregulates the expression of P2X7R and inflammatory factors in microglia. Conversely, it downregulates the expression of P2X7R and inflammatory factors. Conclusion Our study suggests that AST attenuated ATP-P2X7R mediated inflammation in SE.
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Affiliation(s)
- Ming Wang
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, People's Republic of China.,Department of Neurology, Huashan Hospital North, Fudan University, Shanghai, People's Republic of China
| | - Xiaolin Deng
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, People's Republic of China.,Department of Neurology, Huashan Hospital North, Fudan University, Shanghai, People's Republic of China
| | - Yangmei Xie
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, People's Republic of China.,Department of Neurology, Huashan Hospital North, Fudan University, Shanghai, People's Republic of China
| | - Yinghui Chen
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, People's Republic of China.,Department of Neurology, Huashan Hospital North, Fudan University, Shanghai, People's Republic of China
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10
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Scemes E, Velíšek L, Velíšková J. Astrocyte and Neuronal Pannexin1 Contribute Distinctly to Seizures. ASN Neuro 2020; 11:1759091419833502. [PMID: 30862176 PMCID: PMC6415468 DOI: 10.1177/1759091419833502] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
ATP- and adenosine-mediated signaling are prominent types of glia–glia and glia–neuron interaction, with an imbalance of ATP/adenosine ratio leading to altered states of excitability, as seen in epileptic seizures. Pannexin1 (Panx1), a member of the gap junction family, is an ATP release channel that is expressed in astrocytes and neurons. Previous studies provided evidence supporting a role for purinergic-mediated signaling via Panx1 channels in seizures; using mice with global deletion of Panx1, it was shown that these channels contribute in maintenance of seizures by releasing ATP. However, nothing is known about the extent to which astrocyte and neuronal Panx1 might differently contribute to seizures. We here show that targeted deletion of Panx1 in astrocytes or neurons has opposing effects on acute seizures induced by kainic acid. The absence of Panx1 in astrocytes potentiates while the absence of Panx1 in neurons attenuates seizure manifestation. Immunohistochemical analysis performed in brains of these mice, revealed that adenosine kinase (ADK), an enzyme that regulates extracellular levels of adenosine, was increased only in seized GFAP-Cre:Panx1f/f mice. Pretreating mice with the ADK inhibitor, idotubercidin, improved seizure outcome and prevented the increase in ADK immunoreactivity. Together, these data suggest that the worsening of seizures seen in mice lacking astrocyte Panx1 is likely related to low levels of extracellular adenosine due to the increased ADK levels in astrocytes. Our study not only reveals an unexpected link between Panx1 channels and ADK but also highlights the important role played by astrocyte Panx1 channels in controlling neuronal activity.
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Affiliation(s)
- Eliana Scemes
- 1 Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA
| | - Libor Velíšek
- 1 Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA.,2 Departments of Neurology and Pediatrics, New York Medical College, Valhalla, NY, USA
| | - Jana Velíšková
- 1 Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, USA.,3 Departments of Obstetrics & Gynecology and Neurology, New York Medical College, Valhalla, NY, USA
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11
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Alves M, Smith J, Engel T. Differential Expression of the Metabotropic P2Y Receptor Family in the Cortex Following Status Epilepticus and Neuroprotection via P2Y 1 Antagonism in Mice. Front Pharmacol 2020; 10:1558. [PMID: 32009961 PMCID: PMC6976538 DOI: 10.3389/fphar.2019.01558] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 12/03/2019] [Indexed: 12/18/2022] Open
Abstract
Purinergic signaling via P2 receptors is now widely accepted to play a critical role during increased states of hyperexcitability and seizure-induced pathology. In the setting of seizures and epilepsy, most attention has been paid to investigating the fast-acting ATP-gated P2X receptor family. More recent evidence has now also provided compelling evidence of an involvement of the slower-acting P2Y receptor family during seizures. This includes data demonstrating expression changes of P2Y receptors in the hippocampus following acute seizures and during epilepsy and anticonvulsive properties of P2Y-targeting drugs; in particular drugs targeting the P2Y1 subtype. Seizures, however, also involve damage to extra-hippocampal brain regions such as the cortex, which is thought to contribute to the epileptic phenotype. To analyze expressional changes of the P2Y receptor family in the cortex following status epilepticus and to determine the impact of drugs interfering with P2Y1 signaling on cortical damage, we used a unilateral mouse model of intraamygdala kainic acid-induced status epilepticus. Analysis of cortical tissue showed that status epilepticus leads to a global up-regulation of the P2Y receptor family in the cortex including P2Y1, P2Y2, P2Y4, and P2Y6, with the P2Y1 and P2Y4 receptor subtypes showing the strongest increase. Supporting a detrimental role of P2Y1 activation during status epilepticus, treatment with the P2Y1 agonist MRS2365 exacerbated high frequency high amplitude spiking, synonymous with injury-causing electrographic activity, and treatment with the P2Y1 antagonists MRS2500 protected against seizure-induced cortical damage. Suggesting P2Y1-mediated effects are predominantly due to increased microglia activation, treatment with the broad-spectrum anti-inflammatory drug minocycline abolished the observed neuroprotective effects of P2Y1 antagonism. In conclusion, our results further support a role for P2Y1-mediated signaling during seizure generation and seizure-induced neurodegeneration, suggesting P2Y1-targeting therapies as novel treatment for drug-refractory status epilepticus.
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Affiliation(s)
- Mariana Alves
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Jonathon Smith
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland.,FutureNeuro SFI Research Centre, Dublin, Ireland
| | - Tobias Engel
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland.,FutureNeuro SFI Research Centre, Dublin, Ireland
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12
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Terrone G, Frigerio F, Balosso S, Ravizza T, Vezzani A. Inflammation and reactive oxygen species in status epilepticus: Biomarkers and implications for therapy. Epilepsy Behav 2019; 101:106275. [PMID: 31171434 DOI: 10.1016/j.yebeh.2019.04.028] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 04/15/2019] [Indexed: 01/13/2023]
Abstract
Preclinical studies in immature and adult rodents and clinical observations show that neuroinflammation and oxidative stress are rapid onset phenomena occurring in the brain during status epilepticus and persisting thereafter. Notably, both neuroinflammation and oxidative stress contribute to the acute and long-term sequelae of status epilepticus thus representing potential druggable targets. Antiinflammatory drugs that interfere with the IL-1β pathway, such as anakinra, can control benzodiazepine-refractory status epilepticus in animals, and there is recent proof-of-concept evidence for therapeutic effects in children with Febrile infection related epilepsy syndrome (FIRES). Inhibitors of monoacylglycerol lipase and P2X7 receptor antagonists are also promising antiinflammatory drug candidates for rapidly aborting de novo status epilepticus and provide neuroprotection. Antiinflammatory and antioxidant drugs administered to rodents during status epilepticus and transiently thereafter, prevent long-term sequelae such as cognitive deficits and seizure progression in animals developing epilepsy. Some drugs are already in medical use and are well-tolerated, therefore, they may be considered for treating status epilepticus and its neurological consequences. Finally, markers of neuroinflammation and oxidative stress are measureable in peripheral blood and by neuroimaging, which offers an opportunity for developing prognostic and predictive mechanistic biomarkers in people exposed to status epilepticus. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures.
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Affiliation(s)
- Gaetano Terrone
- Department of Translational Medical Sciences, Section of Pediatrics, Federico II University, Naples, Italy
| | - Federica Frigerio
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milano, Italy
| | - Silvia Balosso
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milano, Italy
| | - Teresa Ravizza
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milano, Italy
| | - Annamaria Vezzani
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milano, Italy.
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13
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Zhong R, Chen Q, Li M, Zhang X, Lin W. Elevated Blood C-Reactive Protein Levels in Patients With Epilepsy: A Systematic Review and Meta-Analysis. Front Neurol 2019; 10:974. [PMID: 31620066 PMCID: PMC6759543 DOI: 10.3389/fneur.2019.00974] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 08/27/2019] [Indexed: 01/23/2023] Open
Abstract
Background: In recent years, increasing attention has been paid to the association between C-reactive protein (CRP) levels and epilepsy. However, studies concerning CRP levels in epilepsy have also yielded conflicting results. Thus, the objective of the present study is to systematically review the evidence and conduct a meta-analysis to investigate CRP levels in epileptic patients compared with healthy controls. Methods: A systematic search of PubMed, EMBASE, and the Cochrane Library was performed for eligible studies. Standardized mean differences (SMDs) with 95% confidence intervals (95% CIs) were used as a measure to assess the association between CRP and epilepsy. Results: In total, 16 case–control studies were included in the present meta-analysis, which comprised 1918 individuals. Combined results indicated that epileptic patients had significantly increased CRP levels in peripheral blood compared with healthy controls (SMD = 0.43; 95% CI: 0.19–0.67). In addition, subgroup analyses by age demonstrated that significant differences in blood CRP levels between epileptic patients and healthy controls could be found in adults (SMD = 0.47; 95% CI: 0.21–0.73) but not children (SMD = 0.26; 95% CI: −0.48–0.99). Conclusion: The present meta-analysis shows that the CRP levels in peripheral blood were significantly increased in epileptic patients compared to healthy controls, indicating a significant association between inflammation and epilepsy. Epileptic seizures may be associated with the inflammatory response.
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Affiliation(s)
- Rui Zhong
- Department of Neurology, The First Hospital of Jilin University, Chang Chun, China
| | - Qingling Chen
- Department of Hepatology, The First Hospital of Jilin University, Chang Chun, China
| | - Mengmeng Li
- Department of Neurology, The First Hospital of Jilin University, Chang Chun, China
| | - Xinyue Zhang
- Department of Neurology, The First Hospital of Jilin University, Chang Chun, China
| | - Weihong Lin
- Department of Neurology, The First Hospital of Jilin University, Chang Chun, China
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Context-Specific Switch from Anti- to Pro-epileptogenic Function of the P2Y 1 Receptor in Experimental Epilepsy. J Neurosci 2019; 39:5377-5392. [PMID: 31048325 DOI: 10.1523/jneurosci.0089-19.2019] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/21/2019] [Accepted: 03/23/2019] [Indexed: 12/15/2022] Open
Abstract
Extracellular ATP activates inflammatory responses to tissue injury. It is also implicated in establishing lasting network hyperexcitability in the brain by acting upon independent receptor systems. Whereas the fast-acting P2X channels have well-established roles driving neuroinflammation and increasing hyperexcitability, the slower-acting metabotropic P2Y receptors have received much less attention. Recent studies of P2Y1 receptor function in seizures and epilepsy have produced contradictory results, suggesting that the role of this receptor during seizure pathology may be highly sensitive to context. Here, by using male mice, we demonstrate that the metabotropic P2Y1 receptor mediates either proconvulsive or anticonvulsive responses, dependent on the time point of activation in relation to the induction of status epilepticus. P2Y1 deficiency or a P2Y1 antagonist (MRS2500) administered before a chemoconvulsant, exacerbates epileptiform activity, whereas a P2Y1 agonist (MRS2365) administered at this time point is anticonvulsant. When these drugs are administered after the onset of status epilepticus, however, their effect on seizure severity is reversed, with the antagonist now anticonvulsant and the agonist proconvulsant. This result was consistent across two different mouse models of status epilepticus (intra-amygdala kainic acid and intraperitoneal pilocarpine). Pharmacologic P2Y1 blockade during status epilepticus reduces also associated brain damage, delays the development of epilepsy and, when applied during epilepsy, suppresses spontaneous seizures, in mice. Our data show a context-specific role for P2Y1 during seizure pathology and demonstrate that blocking P2Y1 after status epilepticus and during epilepsy has potent anticonvulsive effects, suggesting that P2Y1 may be a novel candidate for the treatment of drug-refractory status epilepticus and epilepsy.SIGNIFICANCE STATEMENT This is the first study to fully characterize the contribution of a metabotropic purinergic P2Y receptor during acute seizures and epilepsy. The findings suggest that targeting P2Y1 may offer a potential novel treatment strategy for drug-refractory status epilepticus and epilepsy. Our data demonstrate a context-specific role of P2Y1 activation during seizures, switching from a proconvulsive to an anticonvulsive role depending on physiopathological context. Thus, our study provides a possible explanation for seemingly conflicting results obtained between studies of different brain diseases where P2Y1 targeting has been proposed as a potential treatment strategy and highlights that the timing of pharmacological interventions is of critical importance to the understanding of how receptors contribute to the generation of seizures and the development of epilepsy.
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Sepulveda-Rodriguez A, Li P, Khan T, Ma JD, Carlone CA, Bozzelli PL, Conant KE, Forcelli PA, Vicini S. Electroconvulsive Shock Enhances Responsive Motility and Purinergic Currents in Microglia in the Mouse Hippocampus. eNeuro 2019; 6:ENEURO.0056-19.2019. [PMID: 31058213 PMCID: PMC6498419 DOI: 10.1523/eneuro.0056-19.2019] [Citation(s) in RCA: 5] [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: 02/13/2019] [Accepted: 04/09/2019] [Indexed: 12/24/2022] Open
Abstract
Microglia are in a privileged position to both affect and be affected by neuroinflammation, neuronal activity and injury, which are all hallmarks of seizures and the epilepsies. Hippocampal microglia become activated after prolonged, damaging seizures known as status epilepticus (SE). However, since SE causes both hyperactivity and injury of neurons, the mechanisms triggering this activation remain unclear, as does the relevance of the microglial activation to the ensuing epileptogenic processes. In this study, we use electroconvulsive shock (ECS) to study the effect of neuronal hyperactivity without neuronal degeneration on mouse hippocampal microglia. Unlike SE, ECS did not alter hippocampal CA1 microglial density, morphology, or baseline motility. In contrast, both ECS and SE produced a similar increase in ATP-directed microglial process motility in acute slices, and similarly upregulated expression of the chemokine C-C motif chemokine ligand 2 (CCL2). Whole-cell patch-clamp recordings of hippocampal CA1sr microglia showed that ECS enhanced purinergic currents mediated by P2X7 receptors in the absence of changes in passive properties or voltage-gated currents, or changes in receptor expression. This differs from previously described alterations in intrinsic characteristics which coincided with enhanced purinergic currents following SE. These ECS-induced effects point to a "seizure signature" in hippocampal microglia characterized by altered purinergic signaling. These data demonstrate that ictal activity per se can drive alterations in microglial physiology without neuronal injury. These physiological changes, which up until now have been associated with prolonged and damaging seizures, are of added interest as they may be relevant to electroconvulsive therapy (ECT), which remains a gold-standard treatment for depression.
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Affiliation(s)
- Alberto Sepulveda-Rodriguez
- Department of Pharmacology and Physiology, Georgetown University, Washington, DC 20007
- Interdisciplinary Program in Neuroscience, Georgetown University, Washington, DC 20007
| | - Pinggan Li
- Department of Pharmacology and Physiology, Georgetown University, Washington, DC 20007
- Department of Pediatrics, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Tahiyana Khan
- Department of Pharmacology and Physiology, Georgetown University, Washington, DC 20007
- Interdisciplinary Program in Neuroscience, Georgetown University, Washington, DC 20007
| | - James D Ma
- Department of Pharmacology and Physiology, Georgetown University, Washington, DC 20007
| | - Colby A Carlone
- Department of Pharmacology and Physiology, Georgetown University, Washington, DC 20007
| | - P Lorenzo Bozzelli
- Interdisciplinary Program in Neuroscience, Georgetown University, Washington, DC 20007
- Department of Neuroscience, Georgetown University, Washington, DC 20007
| | - Katherine E Conant
- Interdisciplinary Program in Neuroscience, Georgetown University, Washington, DC 20007
- Department of Neuroscience, Georgetown University, Washington, DC 20007
| | - Patrick A Forcelli
- Department of Pharmacology and Physiology, Georgetown University, Washington, DC 20007
- Interdisciplinary Program in Neuroscience, Georgetown University, Washington, DC 20007
| | - Stefano Vicini
- Department of Pharmacology and Physiology, Georgetown University, Washington, DC 20007
- Interdisciplinary Program in Neuroscience, Georgetown University, Washington, DC 20007
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Beamer E, Conte G, Engel T. ATP release during seizures - A critical evaluation of the evidence. Brain Res Bull 2019; 151:65-73. [PMID: 30660718 DOI: 10.1016/j.brainresbull.2018.12.021] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 12/06/2018] [Accepted: 12/20/2018] [Indexed: 01/17/2023]
Abstract
That adenosine 5' triphosphate (ATP) functions as an extracellular signaling molecule has been established since the 1970s. Ubiquitous throughout the body as the principal molecular store of intracellular energy, ATP has a short extracellular half-life and is difficult to measure directly. Extracellular ATP concentrations are dependent both on the rate of cellular release and of enzymatic degradation. Some findings from in vitro studies suggest that extracellular ATP concentrations increase during high levels of neuronal activity and seizure-like events in hippocampal slices. Pharmacological studies suggest that antagonism of ATP-sensitive purinergic receptors can suppress the severity of seizures and block epileptogenesis. Directly measuring extracellular ATP concentrations in the brain, however, has a number of specific challenges, notably, the rapid hydrolysis of ATP and huge gradient between intracellular and extracellular compartments. Two studies using microdialysis found no change in extracellular ATP in the hippocampus of rats during experimentally-induced status epilepticus. One of which demonstrated that ATP increased measurably, only in the presence of ectoATPase inhibitors, with the other study demonstrating increases only during later spontaneous seizures. Current evidence is mixed and seems highly dependent on the model used and method of detection. More sensitive methods of detection with higher spatial resolution, which induce less tissue disruption will be necessary to provide evidence for or against the hypothesis of seizure-induced elevations in extracellular ATP. Here we describe the current hypothesis for ATP release during seizures and its role in epileptogenesis, describe the technical challenges involved and critically examine the current evidence.
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Affiliation(s)
- Edward Beamer
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02YN77, Dublin, Ireland.
| | - Giorgia Conte
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02YN77, Dublin, Ireland
| | - Tobias Engel
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02YN77, Dublin, Ireland
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17
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Wang M, Chen Y. Inflammation: A Network in the Pathogenesis of Status Epilepticus. Front Mol Neurosci 2018; 11:341. [PMID: 30344475 PMCID: PMC6182087 DOI: 10.3389/fnmol.2018.00341] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 08/30/2018] [Indexed: 12/17/2022] Open
Abstract
Status epilepticus (SE) is an abnormally prolonged or recurrent epileptic seizure that is a serious, life-threatening medical emergency. Notably, it requires prompt and aggressive treatment. SE is characterized by high mortality and morbidity. However, its pathogenesis remains unclear. Numerous studies of SE have reported widespread brain inflammation, suggesting that inflammation plays a vital role in the occurrence and development of SE. This mini review article reviews the current knowledge with regard to the role of inflammation in SE.
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Affiliation(s)
- Ming Wang
- Department of Neurology, Jinshan Hospital, Fudan University, Shanghai, China
| | - Yinghui Chen
- Department of Neurology, Huashan Hospital North, Fudan University, Shanghai, China
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18
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Sun H, Ma L, Zhang Y, Pan X, Wang C, Zhang J, Zhang X, Sun H, Wang Q, Zhu W. A Purinergic P2 Receptor Family-Mediated Increase in Thrombospondin-1 Bolsters Synaptic Density and Epileptic Seizure Activity in the Amygdala-Kindling Rat Model. Front Cell Neurosci 2018; 12:302. [PMID: 30386206 PMCID: PMC6199899 DOI: 10.3389/fncel.2018.00302] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 08/20/2018] [Indexed: 01/08/2023] Open
Abstract
Previous studies suggested that the thrombospondin-1/transforming growth factor-β1 (TSP-1/TGF-β1) pathway might be critical in synaptogenesis during development and that the purinergic P2 receptor family could regulate synaptogenesis by modulating TSP-1 signaling. However, it is unclear whether this pathway plays a role in synaptogenesis during epileptic progression. This study was designed to investigate this question by analyzing the dynamic changes and effects of TSP-1 levels on the density of synaptic markers that are related to epileptic seizure activity. In addition, we evaluated whether P2-type receptors could regulate these effects. We generated a rat seizure model via amygdala kindling and inhibited TSP-1 activity using small interfering RNA (siRNA) interference and pharmacological inhibition. We treated the rats with antagonists of P2 or P2Y receptors, pyridoxalphosphate-6-azophenyl-2’,4’-disulfonic (PPADS) or Reactive Blue 2. Following this, we quantified TSP-1 and TGF-β1 immunoreactivity (IR), the density of synaptic markers, and seizure activity. There were significantly more synapses/excitatory synapses in several brain regions, such as the hippocampus, which were associated with progressing epileptic discharges after kindling. These were associated with increased TSP-1 and TGF-β1-IR. Genetic or pharmacologic inhibition of TSP-1 significantly reduced the density of synaptic/excitatory synaptic markers and inhibited the generalization of focal epilepsy. The administration of PPADS or Reactive Blue 2 attenuated the increase in TSP-1-IR and the increase in the density of synaptic markers that follows kindling and abolished most of the epileptic seizure activity. Altogether, our results indicate that the TSP-1/TGF-β1 pathway and its regulation by P2, particularly P2Y-type receptors, may be a critical promoter of synaptogenesis during the progression of epilepsy. Therefore, components of this pathway may be targets for novel antiepileptic drug development.
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Affiliation(s)
- Hongliu Sun
- School of Pharmaceutical Sciences, Binzhou Medical University Yantai, China
| | - Luyu Ma
- Shandong Academy of Medical Sciences (SDAMS) Jinan, China
| | - Yurong Zhang
- School of Pharmaceutical Sciences, Binzhou Medical University Yantai, China
| | - Xiaohong Pan
- School of Pharmaceutical Sciences, Binzhou Medical University Yantai, China
| | - Chaoyun Wang
- School of Pharmaceutical Sciences, Binzhou Medical University Yantai, China
| | - Jinjin Zhang
- School of Pharmaceutical Sciences, Binzhou Medical University Yantai, China
| | - Xiuli Zhang
- School of Pharmaceutical Sciences, Binzhou Medical University Yantai, China
| | - Hongwei Sun
- School of Pharmaceutical Sciences, Binzhou Medical University Yantai, China
| | - Qiaoyun Wang
- School of Pharmaceutical Sciences, Binzhou Medical University Yantai, China
| | - Wei Zhu
- Shandong Academy of Medical Sciences (SDAMS) Jinan, China
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Amengual-Gual M, Sánchez Fernández I, Wainwright MS. Novel drugs and early polypharmacotherapy in status epilepticus. Seizure 2018; 68:79-88. [PMID: 30473267 DOI: 10.1016/j.seizure.2018.08.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 08/05/2018] [Indexed: 12/11/2022] Open
Abstract
PURPOSE Rescue medications for status epilepticus (SE) have a relatively high rate of failure. The purpose of this review is to summarize the evidence for the efficacy of novel drugs and early polypharmacotherapy for SE. METHOD Literature review. RESULTS New drugs and treatment strategies aim to target the pathophysiology of SE in order to improve seizure control and outcomes. Changes at the synapse level during SE include a progressive decrease in synaptic GABAA receptors and increase in synaptic NMDA receptors. These changes tend to promote self-sustaining seizures. Current SE guidelines recommend a rapid stepwise treatment using benzodiazepines in monotherapy as the first-line treatment, targeting GABAA synaptic receptors. Novel treatment approaches target GABAA synaptic and extrasynaptic receptors with allopregnanolone, and NMDA receptors with ketamine. Novel rescue treatments used for SE include topiramate, brivaracetam, and perampanel, which are already marketed in epilepsy. Some available drugs not marketed for use in epilepsy have been used in the treatment of SE, and other agents are being studied for this purpose. Early polytherapy, most frequently combining a benzodiazepine with a second-line drug or an NMDA receptor antagonist, might potentially increase seizure control with relatively minor increase in side effects. Although many preclinical studies support novel drugs and early polytherapy in SE, human studies are scarce and inconclusive. Currently, evidence is lacking to recommend specific combinations of these new agents. CONCLUSIONS Novel drugs and strategies target the underlying pathophysiology of SE with the intent to improve seizure control and outcomes.
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Affiliation(s)
- Marta Amengual-Gual
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Pediatric Neurology Unit, Department of Pediatrics, Hospital Universitari Son Espases, Universitat de les Illes Balears, Palma, Spain.
| | - Iván Sánchez Fernández
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Child Neurology, Hospital Sant Joan de Déu, Universidad de Barcelona, Spain
| | - Mark S Wainwright
- Department of Neurology, Division of Pediatric Neurology. University of Washington School of Medicine, Seattle, WA, USA
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20
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Expression Analysis of CYFIP1 and CAMKK2 Genes in the Blood of Epileptic and Schizophrenic Patients. J Mol Neurosci 2018; 65:336-342. [PMID: 29992499 DOI: 10.1007/s12031-018-1106-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 06/15/2018] [Indexed: 12/27/2022]
Abstract
Schizophrenia and epilepsy are two prevalent neurological disorders with high global burden to the society. Genome-wide studies have identified potential underlying causes for these neurological diseases. In the present case-control study, we have assessed expression of CYFIP1 and CAMKK2 genes in the blood samples of epileptic and schizophrenic patients compared with healthy subjects. A total of 180 subjects including 40 epileptic patients, 50 schizophrenic patients, and 90 healthy individuals participated in the study. Expression of the mentioned genes was measured using TaqMan real-time PCR. The results demonstrated a significant upregulation of CYFIP1 gene expression in epileptic patients (P = 0.029). CAMKK2 was downregulated in female schizophrenic patients compared with female healthy individuals (P = 0.048). These results may provide new insight into the pathogenesis of epilepsy and schizophrenia and suggest these genes as potential therapeutic targets for these neurological disorders. Future studies should evaluate these results in larger cohorts of patients.
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21
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New Insights into Microglia-Neuron Interactions: A Neuron's Perspective. Neuroscience 2018; 405:103-117. [PMID: 29753862 DOI: 10.1016/j.neuroscience.2018.04.046] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 04/26/2018] [Accepted: 04/28/2018] [Indexed: 01/16/2023]
Abstract
Microglia are the primary immune cells of the central nervous system. However, recent data indicate that microglia also contribute to diverse physiological and pathophysiological processes that extend beyond immune-related functions and there is a growing interest to understand the mechanisms through which microglia interact with other cells in the brain. In particular, the molecular processes that contribute to microglia-neuron communication in the healthy brain and their role in common brain diseases have been intensively studied during the last decade. In line with this, fate-mapping studies, genetic models and novel pharmacological approaches have revealed the origin of microglial progenitors, demonstrated the role of self-maintaining microglial populations during brain development or in adulthood, and identified the unexpectedly long lifespan of microglia that may profoundly change our view about senescence and age-related human diseases. Despite the exponentially increasing knowledge about microglia, the role of these cells in health and disease is still extremely controversial and the precise molecular targets for intervention are not well defined. This is in part due to the lack of microglia-specific manipulation approaches until very recently and to the high level of complexity of the interactions between microglia and other cells in the brain that occur at different temporal and spatial scales. In this review, we briefly summarize the known physiological roles of microglia-neuron interactions in brain homeostasis and attempt to outline some major directions and challenges of future microglia research.
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22
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Vezzani A, Dingledine R, Rossetti AO. Immunity and inflammation in status epilepticus and its sequelae: possibilities for therapeutic application. Expert Rev Neurother 2018; 15:1081-92. [PMID: 26312647 DOI: 10.1586/14737175.2015.1079130] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Status epilepticus (SE) is a life-threatening neurological emergency often refractory to available treatment options. It is a very heterogeneous condition in terms of clinical presentation and causes, which besides genetic, vascular and other structural causes also include CNS or severe systemic infections, sudden withdrawal from benzodiazepines or anticonvulsants and rare autoimmune etiologies. Treatment of SE is essentially based on expert opinions and antiepileptic drug treatment per se seems to have no major impact on prognosis. There is, therefore, urgent need of novel therapies that rely upon a better understanding of the basic mechanisms underlying this clinical condition. Accumulating evidence in animal models highlights that inflammation ensuing in the brain during SE may play a determinant role in ongoing seizures and their long-term detrimental consequences, independent of an infection or auto-immune cause; this evidence encourages reconsideration of the treatment flow in SE patients.
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Affiliation(s)
- Annamaria Vezzani
- a 1 Department of Neuroscience, Mario Negri Institute for Pharmacological Research, Milano, Italy
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23
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Li X, Liu H, Yang Y. Magnesium sulfate attenuates brain edema by lowering AQP4 expression and inhibits glia-mediated neuroinflammation in a rodent model of eclampsia. Behav Brain Res 2017; 364:403-412. [PMID: 29288747 DOI: 10.1016/j.bbr.2017.12.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 12/23/2017] [Accepted: 12/26/2017] [Indexed: 12/26/2022]
Abstract
Eclampsia is characterized by high morbidity and mortality wordwide. Magnesium sulfate (MgSO4) is used frequently as a prophylaxis for eclamptic seizure in clinical settings. However, the underlying mechanism is less studied, we have previously demonstrated that MgSO4 pretreatment decreases eclampsia-like seizure threshold. Here, we further evaluated the hypothesis that MgSO4 exert neuroprotective actions in eclampsia-like rats model by ameliorating neuroinflammation and brain edema. In this study, the eclampsia-like model was established by administering lipopolysaccharide plus pentylenetetrazol in pregnant Sprague-Dawley rats. Rats were given MgSO4 from gestation day14-19. Then, Iba-1 (a marker for microglia) and S100-B (a marker for astrocytes) expression levels in the hippocampus CA3 region were detected by Enzyme-linked immunosorbent assay. Cerebrospinal fluid (CSF) levels of inflammatory cytokines were measured by Luminex assays. Aquaporin-4 (a transmembrane water channel protein) expression levels in cortex were analyzed using immunohistochemistry. Astrocyte and microglia expressions were detected by immunofluorescence, neuronal damage were evaluated by Nissl staining, and changes in neuronal number in the hippocampal CA3 region (CA3) among different groups were detected by neuronal nuclei staining. Our results demonstrated that MgSO4 effectively attenuated astrocyte and microglia activation and promoted the neuronal survival in the CA3. Additionally, MgSO4 significantly reduced inflammatory cytokines response in the CSF, and decreased the expression of AQP-4 protein in the cortex. Collectively, the findings of this study indicated that MgSO4 has a neuroprotective role in eclampsia-like seizure rats through its anti-neuroninflammatory and brain edema-attenuating properties.
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Affiliation(s)
- Xiaolan Li
- Department of Obstetrics and Gynaecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China; Department of Obstetrics, Guangzhou Women and Children's Medical Center, China; Anhui Province Key Laboratory of Reproductive Health and Genetics, Anhui Medical University, Hefei, China
| | - Huishu Liu
- Department of Obstetrics, Guangzhou Women and Children's Medical Center, China
| | - Yuanyuan Yang
- Department of Obstetrics and Gynaecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China; Anhui Province Key Laboratory of Reproductive Health and Genetics, Anhui Medical University, Hefei, China.
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24
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Amorim RP, Araújo MGL, Valero J, Lopes-Cendes I, Pascoal VDB, Malva JO, da Silva Fernandes MJ. Silencing of P2X7R by RNA interference in the hippocampus can attenuate morphological and behavioral impact of pilocarpine-induced epilepsy. Purinergic Signal 2017; 13:467-478. [PMID: 28707031 PMCID: PMC5714836 DOI: 10.1007/s11302-017-9573-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Accepted: 06/28/2017] [Indexed: 12/01/2022] Open
Abstract
Cell signaling mediated by P2X7 receptors (P2X7R) has been suggested to be involved in epileptogenesis, via modulation of intracellular calcium levels, excitotoxicity, activation of inflammatory cascades, and cell death, among other mechanisms. These processes have been described to be involved in pilocarpine-induced status epilepticus (SE) and contribute to hyperexcitability, resulting in spontaneous and recurrent seizures. Here, we aimed to investigate the role of P2X7R in epileptogenesis in vivo using RNA interference (RNAi) to inhibit the expression of this receptor. Small interfering RNA (siRNA) targeting P2X7R mRNA was injected into the lateral ventricles (icv) 6 h after SE. Four groups were studied: Saline-Vehicle, Saline-siRNA, Pilo-Vehicle, and Pilo-siRNA. P2X7R was quantified by western blotting and neuronal death assessed by Fluoro-Jade B histochemistry. The hippocampal volume (edema) was determined 48 h following RNAi. Behavioral parameters as latency to the appearance of spontaneous seizures and the number of seizures were determined until 60 days after the SE onset. The Saline-siRNA and Pilo-siRNA groups showed a 43 and 37% reduction, respectively, in P2X7R protein levels compared to respective vehicle groups. Neuroprotection was observed in CA1 and CA3 of the Pilo-siRNA group compared to Pilo-Vehicle. P2X7R silencing in pilocarpine group reversed the increase in the edema detected in the hilus, suprapyramidal dentate gyrus, CA1, and CA3; reduced mortality rate following SE; increased the time to onset of spontaneous seizure; and reduced the number of seizures, when compared to the Pilo-Vehicle group. Therefore, our data highlights the potential of P2X7R as a therapeutic target for the adjunct treatment of epilepsy.
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Affiliation(s)
- Rebeca Padrão Amorim
- Departamento de Neurologia e Neurocirurgia, Disciplina de Neurociência, Universidade Federal de São Paulo, Rua Pedro de Toledo 669, 2° andar, São Paulo, SP, CEP 04039-032, Brazil
| | - Michelle Gasparetti Leão Araújo
- Departamento de Neurologia e Neurocirurgia, Disciplina de Neurociência, Universidade Federal de São Paulo, Rua Pedro de Toledo 669, 2° andar, São Paulo, SP, CEP 04039-032, Brazil
| | - Jorge Valero
- Centro de Neurociências e Biologia Celular, Universidade de Coimbra, Coimbra, Portugal
- Achucarro Basque Center for Neuroscience, Zamudio, Bizkaia, Spain
- Ikerbasque Basque Foundation for Science, Bilbao, Bizkaia, Spain
| | - Iscia Lopes-Cendes
- Departamento de Genética Médica, Faculdade de Medicina da Unicamp, Campinas, SP, Brazil
| | | | - João Oliveira Malva
- Institute of Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Maria José da Silva Fernandes
- Departamento de Neurologia e Neurocirurgia, Disciplina de Neurociência, Universidade Federal de São Paulo, Rua Pedro de Toledo 669, 2° andar, São Paulo, SP, CEP 04039-032, Brazil.
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Lanser AJ, Rezende RM, Rubino S, Lorello PJ, Donnelly DJ, Xu H, Lau LA, Dulla CG, Caldarone BJ, Robson SC, Weiner HL. Disruption of the ATP/adenosine balance in CD39 -/- mice is associated with handling-induced seizures. Immunology 2017; 152:589-601. [PMID: 28742222 DOI: 10.1111/imm.12798] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 07/15/2017] [Accepted: 07/16/2017] [Indexed: 12/14/2022] Open
Abstract
Seizures are due to excessive, synchronous neuronal firing in the brain and are characteristic of epilepsy, the fourth most prevalent neurological disease. We report handling-induced and spontaneous seizures in mice deficient for CD39, a cell-surface ATPase highly expressed on microglial cells. CD39-/- mice with handling-induced seizures had normal input-output curves and paired-pulse ratio measured from hippocampal slices and lacked microgliosis, astrogliosis or overt cell loss in the hippocampus and cortex. As expected, however, the cerebrospinal fluid of CD39-/- mice contained increased levels of ATP and decreased levels of adenosine. To determine if immune activation was involved in seizure progression, we challenged mice with lipopolysaccharide (LPS) and measured the effect on microglia activation and seizure severity. Systemic LPS challenge resulted in increased cortical staining of Iba1/CD68 and gene array data from purified microglia predicted increased expression of interleukin-8, triggering receptor expressed on myeloid cells 1, p38, pattern recognition receptors, death receptor, nuclear factor-κB , complement, acute phase, and interleukin-6 signalling pathways in CD39-/- versus CD39+/+ mice. However, LPS treatment did not affect handling-induced seizures. In addition, microglia-specific CD39 deletion in adult mice was not sufficient to cause seizures, suggesting instead that altered expression of CD39 during development or on non-microglial cells such as vascular endothelial cells may promote the seizure phenotype. In summary, we show a correlation between altered extracellular ATP/adenosine ratio and a previously unreported seizure phenotype in CD39-/- mice. This work provides groundwork for further elucidation of the underlying mechanisms of epilepsy.
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Affiliation(s)
- Amanda J Lanser
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Rafael M Rezende
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Stephen Rubino
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Paul J Lorello
- NeuroBehavior Laboratory, Harvard NeuroDiscovery Center, Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA
| | - Dustin J Donnelly
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Huixin Xu
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Lauren A Lau
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Chris G Dulla
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Barbara J Caldarone
- NeuroBehavior Laboratory, Harvard NeuroDiscovery Center; Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Simon C Robson
- Liver Center and The Transplant Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Howard L Weiner
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Abstract
OBJECTIVE Epilepsy is a chronic neurological disease characterised with seizures. The aetiology of the most generalised epilepsies cannot be explicitly determined and the seizures are pronounced to be genetically determined by disturbances of receptors in central nervous system. Besides, neurotransmitter distributions or other metabolic problems are supposed to involve in epileptogenesis. Lack of adequate data about pharmacological agents that have antiepileptogenic effects point to need of research on this field. Thus, in this review, inflammatory aspects of epileptogenesis has been focussed via considering several concepts like role of immune system, blood-brain barrier and antibody involvement in epileptogenesis. METHODS We conducted an evidence-based review of the literatures in order to evaluate the possible participation of inflammatory processes to epileptogenesis and also, promising agents which are effective to these processes. We searched PubMed database up to November 2015 with no date restrictions. RESULTS In the present review, 163 appropriate articles were included. Obtained data suggests that inflammatory processes participate to epileptogenesis in several ways like affecting fibroblast growth factor-2 and tropomyosin receptor kinase B signalling pathways, detrimental proinflammatory pathways [such as the interleukin-1 beta (IL-1β)-interleukin-1 receptor type 1 (IL-1R1) system], mammalian target of rapamycin pathway, microglial activities, release of glial inflammatory proteins (such as macrophage inflammatory protein, interleukin 6, C-C motif ligand 2 and IL-1β), adhesion molecules that are suggested to function in signalling pathways between neurons and microglia and also linkage between these molecules and proinflammatory cytokines. CONCLUSION The literature research indicated that inflammation is a part of epileptogenesis. For this reason, further studies are necessary for assessing agents that will be effective in clinical use for therapeutic treatment of epileptogenesis.
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Abstract
INTRODUCTION The P2X7 receptor (P2X7R) is a unique subtype among the family of seven purinergic P2X receptors, which are ATP-gated non-selective cation channels. P2X7R has been reported to have pathological roles in various diseases, including autoimmune diseases such as arthritis and inflammatory bowel disease, neurodegenerative diseases, chronic pain, mood disorders and cancers. Therefore, many pharmaceutical companies have endeavored to develop a clinical candidate targeting P2X7R. Areas covered: This review provides a summary of various patents on chemicals and biologics and their clinical use published between 2010 and 2015. The reader will gain information on structural claims, representative structures and biological activities of recently developed P2X7R antagonists. Expert opinion: P2X7R is a fascinating therapeutic target and potential biomarker for inflammation, pain disorders and cancers. Research on the development of P2X7R antagonists has continually increased despite the failure of AstraZeneca and Merck's compounds in phase II clinical trials. Various scaffolds have been disclosed by several pharmaceutical industries, and some compounds are currently under investigation in clinical trials.
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Affiliation(s)
- Jin-Hee Park
- a School of Life Sciences , Gwangju Institute of Science & Technology , Gwangju , Republic of Korea.,b New Drug Development Center (NDDC) , Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF) , Daegu , Republic of Korea
| | - Yong-Chul Kim
- a School of Life Sciences , Gwangju Institute of Science & Technology , Gwangju , Republic of Korea.,c Department of Biomedical Science and Engineering , Gwangju Institute of Science & Technology , Gwangju , Republic of Korea
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The evolution of P2X7 antagonists with a focus on CNS indications. Bioorg Med Chem Lett 2016; 26:3838-45. [PMID: 27426304 DOI: 10.1016/j.bmcl.2016.06.048] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 06/08/2016] [Accepted: 06/16/2016] [Indexed: 12/11/2022]
Abstract
The P2X7 receptor is an ATP-gated nonselective cation channel that has been linked to a number of inflammatory diseases. Activation of the P2X7 receptor by elevated levels of ATP results in the release of proinflammatory cytokines and elevated levels of these cytokines has been associated with a variety of disease states. A number of research groups in both industry and academia have explored the identification of P2X7R antagonists as therapeutic agents. Much of this early effort focused on the treatment of diseases related to peripheral inflammation and resulted in several clinical candidates, none of which were advanced to market. The emerging role of the P2X7 receptor in neuroinflammation and related diseases has resulted in a shift in medicinal chemistry efforts toward the development of centrally penetrant antagonists. This review will highlight the biology supporting the role of P2X7 in diseases related to neuroinflammation and review the recent medicinal chemistry efforts to identify centrally penetrant antagonists.
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Bhattacharya A, Biber K. The microglial ATP-gated ion channel P2X7 as a CNS drug target. Glia 2016; 64:1772-87. [PMID: 27219534 DOI: 10.1002/glia.23001] [Citation(s) in RCA: 151] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 04/17/2016] [Accepted: 04/18/2016] [Indexed: 12/14/2022]
Abstract
Based on promising preclinical evidence, microglial P2X7 has increasingly being recognized as a target for therapeutic intervention in neurological and psychiatric diseases. However, despite this knowledge no P2X7-related drug has yet entered clinical trials with respect to CNS diseases. We here discuss the current literature on P2X7 being a drug target and identify unsolved issues and still open questions that have hampered the development of P2X7 dependent therapeutic approaches for CNS diseases. It is concluded here that the lack of brain penetrating P2X7 antagonists is a major obstacle in the field and that central P2X7 is a yet untested clinical drug target. In the CNS, microglial P2X7 activation causes neuroinflammation, which in turn plays a role in various CNS disorders. This has resulted in a surge of brain penetrant P2X7 antagonists. P2X7 is a viable, clinically untested CNS drug target. GLIA 2016;64:1772-1787.
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Affiliation(s)
- Anindya Bhattacharya
- LLC. Neuroscience Drug Discovery, Janssen Research & Development, 3210 Merryfield Row, San Diego, California
| | - Knut Biber
- Department of Psychiatry and Psychotherapy, University Hospital Freiburg, Hauptstrasse 5, Freiburg, Germany.,Department of Neuroscience, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, AV Groningen, The Netherlands
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30
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Engel T. Purinergic signaling-induced neuroinflammation and status epilepticus. Expert Rev Neurother 2016; 16:735-7. [DOI: 10.1586/14737175.2016.1164036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Tobias Engel
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland
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Umpierre AD, Bennett IV, Nebeker LD, Newell TG, Tian BB, Thomson KE, White HS, White JA, Wilcox KS. Repeated low-dose kainate administration in C57BL/6J mice produces temporal lobe epilepsy pathology but infrequent spontaneous seizures. Exp Neurol 2016; 279:116-126. [PMID: 26896834 DOI: 10.1016/j.expneurol.2016.02.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/29/2016] [Accepted: 02/15/2016] [Indexed: 12/31/2022]
Abstract
More efficient or translationally relevant approaches are needed to model acquired temporal lobe epilepsy (TLE) in genetically tractable mice. The high costs associated with breeding and maintaining transgenic, knock-in, or knock-out lines place a high value on the efficiency of induction and animal survivability. Herein, we describe our approaches to model acquired epilepsy in C57BL/6J mice using repeated, low-dose kainate (KA) administration paradigms. Four paradigms (i.p.) were tested for their ability to induce status epilepticus (SE), temporal lobe pathology, and the development of epilepsy. All four paradigms reliably induce behavioral and/or electrographic SE without mortality over a 7d period. Two of the four paradigms investigated produce features indicative of TLE pathology, including hippocampal cell death, widespread astrogliosis, and astrocyte expression of mGluR5, a feature commonly reported in TLE models. Three of the investigated paradigms were able to produce aberrant electrographic features, such as interictal spiking in cortex. However, only one paradigm, previously published by others, produces spontaneous recurrent seizures over an eight week period. Presentation of spontaneous seizures is rare (N=2/14), with epilepsy preferentially developing in animals having a high number of seizures during SE. Overall, repeated, low-dose KA administration improves the efficiency and pathological relevance of a systemic KA insult, but does not produce a robust epilepsy phenotype under the experimental paradigms described herein.
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Affiliation(s)
- Anthony D Umpierre
- Interdepartmental Program in Neuroscience, University of Utah, 401 MREB, 20N. 1900E, Salt Lake City, UT 84132, United States.
| | - Isaiah V Bennett
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Lismore D Nebeker
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Thomas G Newell
- Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Dept. of Bioengineering, University of Utah, 36S. Wasatch Drive, Rm. 3100, Salt Lake City, UT 84112, United States.
| | - Bruce B Tian
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Kyle E Thomson
- Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Dept. of Bioengineering, University of Utah, 36S. Wasatch Drive, Rm. 3100, Salt Lake City, UT 84112, United States.
| | - H Steve White
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States; Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Department of Pharmacy, University of Washington, Box 357630, H375 Health Science Building, Seattle, WA 98195, United States.
| | - John A White
- Dept. of Biomedical Engineering, Boston University, 44 Cummington Mall, Rm. 403, Boston, MA 02215, United States.
| | - Karen S Wilcox
- Interdepartmental Program in Neuroscience, University of Utah, 401 MREB, 20N. 1900E, Salt Lake City, UT 84132, United States; Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States; Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States.
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Siepmann T, Barlinn K, Penzlin AI, Illigens BMW, Kitzler H, Bodechtel U. Subsequent Bilateral Hippocampal Diffusion Restriction and Atrophy in Repeated Status Epilepticus. Neurodiagn J 2016; 55:243-50. [PMID: 26793901 DOI: 10.1080/21646821.2015.1071143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Cortical lesions in status epilepticus have been reported but the underlying mechanisms are poorly elucidated. CASE SUMMARY We report on afemale patient (75 years) with a history of alcohol abuse who presented with complex partial status epilepticus and lateralized epileptiform discharges in the left frontal and temporal regions in EEG. While cranial magnetic resonance imaging (MRI) showed left hippocampal T2-hyperintensity and diffusion restriction, cerebrospinal fluid was normal and revealed no limbic encephalitis-related antibodies. Following treatment with levitiracetam, seizures ceased and the patient was dismissed. Nine months later, she was readmitted with generalized status epilepticus. Cranial MI now showed hippocampal diffusion restriction and T2 hyperintensity, but in the right hemisphere, as well as atrophy and partial gliotic transformation of the initially affected left hippocampus. DISCUSSION Although hippocampal damage due to antibody-negative limbic encephalitis cannot be ruled out, our observation of subsequent bilateral hippocampal diffusion restriction with gliotic transformation may demonstrate permanent seizure-induced structural brain damage and underlines the importance of further research to elucidate the effects of prolonged epileptic discharges on cerebral structural integrity.
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Amhaoul H, Ali I, Mola M, Van Eetveldt A, Szewczyk K, Missault S, Bielen K, Kumar-Singh S, Rech J, Lord B, Ceusters M, Bhattacharya A, Dedeurwaerdere S. P2X7 receptor antagonism reduces the severity of spontaneous seizures in a chronic model of temporal lobe epilepsy. Neuropharmacology 2016; 105:175-185. [PMID: 26775823 DOI: 10.1016/j.neuropharm.2016.01.018] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 01/05/2016] [Accepted: 01/12/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND The available pharmacotherapy for patients with epilepsy primarily address the symptoms and are ineffective in about 40% of patients. Brain inflammation gained support as potential target for developing new therapies, especially the P2X7 receptor (P2X7R), involved in processing of IL-1β, might be an interesting candidate. This study was designed to investigate the effect of a novel P2X7R antagonist on the severity and on the number of chronic spontaneous recurrent seizures (SRS), which was unexplored until now. METHODS After one-week of vehicle treatment (20% HP-β-cyclodextrin), JNJ-42253432 was administered subcutaneously for another week under continuous video-electroencephalography monitoring (n = 17) in Sprague Dawley rats 3 months after kainic acid-induced status epilepticus. The proportion of different seizure classes, as well as the number of SRS/day were calculated for the vehicle and treatment period. In addition, post-mortem microglial activation and astrogliosis were assessed. RESULTS A significant decrease of the proportion of type 4-5 SRS (p < 0.05), while an increase of type 1-3 was demonstrated (p < 0.05) from the vehicle to the treatment period. There was no effect of the P2X7R antagonist on the number of SRS/day or the glial markers. CONCLUSIONS The P2X7R antagonist gave rise to a less severe profile of the chronic seizure burden without suppressing the SRS frequency. More studies are needed to unravel the underlying mechanisms of the beneficial effect on seizure severity and whether the administration of the compound during early epileptogenesis could induce long-term disease-modifying effects.
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Affiliation(s)
- Halima Amhaoul
- Department of Translational Neurosciences, University of Antwerp, Wilrijk, Belgium
| | - Idrish Ali
- Department of Translational Neurosciences, University of Antwerp, Wilrijk, Belgium
| | - Marco Mola
- Department of Translational Neurosciences, University of Antwerp, Wilrijk, Belgium
| | - Annemie Van Eetveldt
- Department of Translational Neurosciences, University of Antwerp, Wilrijk, Belgium
| | - Krystyna Szewczyk
- Department of Translational Neurosciences, University of Antwerp, Wilrijk, Belgium
| | - Stephan Missault
- Department of Translational Neurosciences, University of Antwerp, Wilrijk, Belgium
| | - Kenny Bielen
- Laboratory of Cell Biology and Histology, University of Antwerp, Antwerp, Belgium
| | - Samir Kumar-Singh
- Department of Translational Neurosciences, University of Antwerp, Wilrijk, Belgium; Laboratory of Cell Biology and Histology, University of Antwerp, Antwerp, Belgium
| | - Jason Rech
- Neuroscience Therapeutic Area, Janssen Research & Development, San Diego, USA
| | - Brian Lord
- Neuroscience Therapeutic Area, Janssen Research & Development, San Diego, USA
| | - Marc Ceusters
- Neuroscience Therapeutic Area, Janssen Research & Development, Beerse, Belgium
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Upregulated P2X3 Receptor Expression in Patients with Intractable Temporal Lobe Epilepsy and in a Rat Model of Epilepsy. Neurochem Res 2016; 41:1263-73. [DOI: 10.1007/s11064-015-1820-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 12/24/2015] [Accepted: 12/29/2015] [Indexed: 12/11/2022]
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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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Ho YH, Lin YT, Wu CWJ, Chao YM, Chang AYW, Chan JYH. Peripheral inflammation increases seizure susceptibility via the induction of neuroinflammation and oxidative stress in the hippocampus. J Biomed Sci 2015; 22:46. [PMID: 26100815 PMCID: PMC4477313 DOI: 10.1186/s12929-015-0157-8] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 06/13/2015] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Neuroinflammation with activation of microglia and production of proinflammatory cytokines in the brain plays an active role in epileptic disorders. Brain oxidative stress has also been implicated in the pathogenesis of epilepsy. Damage in the hippocampus is associated with temporal lobe epilepsy, a common form of epilepsy in human. Peripheral inflammation may exacerbate neuroinflammation and brain oxidative stress. This study examined the impact of peripheral inflammation on seizure susceptibility and the involvement of neuroinflammation and oxidative stress in the hippocampus. RESULTS In male, adult Sprague-Dawley rats, peripheral inflammation was induced by the infusion of Escherichia coli lipopolysaccharide (LPS, 2.5 mg/kg/day) into the peritoneal cavity for 7 days via an osmotic minipump. Pharmacological agents were delivered via intracerebroventricular (i.c.v.) infusion with an osmotic minipump. The level of cytokine in plasma or hippocampus was analyzed by ELISA. Redox-related protein expression in hippocampus was evaluated by Western blot. Seizure susceptibility was tested by intraperitoneal (i.p.) injection of kainic acid (KA, 10 mg/kg). We found that i.p. infusion of LPS for 7 days induced peripheral inflammation characterized by the increases in plasma levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). This is associated with a significant increase in number of the activated microglia (Iba-1(+) cells), enhanced production of proinflammatory cytokines (including IL-1β, IL-6 and TNF-α), and tissue oxidative stress (upregulations of the NADPH oxidase subunits) in the hippocampus. These cellular and molecular responses to peripheral inflammation were notably blunted by i.c.v. infusion of a cycloxygenase-2 inhibitor, NS398 (5 μg/μl/h). The i.c.v. infusion of tempol (2.5 μg/μl/h), a reactive oxygen species scavenger, protected the hippocampus from oxidative damage with no apparent effect on microglia activation or cytokine production after peripheral inflammation. In the KA-induced seizure model, i.c.v. infusion of both NS398 and tempol ameliorated the increase in seizure susceptibility in animals succumbed to the LPS-induced peripheral inflammation. CONCLUSIONS Together these results indicated that LPS-induced peripheral inflammation evoked neuroinflammation and the subsequent oxidative stress in the hippocampus, resulting in the increase in KA-induced seizure susceptibility. Moreover, protection from neuroinflammation and oxidative stress in the hippocampus exerted beneficial effect on seizure susceptibility following peripheral inflammation.
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Affiliation(s)
- Ying-Hao Ho
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, 804, Taiwan.
- Division of Neurology, Kaohsiung Veterans General Hospital, Kaohsiung, 813, Taiwan.
| | - Yu-Te Lin
- Division of Neurology, Kaohsiung Veterans General Hospital, Kaohsiung, 813, Taiwan.
| | - Chih-Wei J Wu
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 833, Taiwan.
| | - Yung-Mei Chao
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 833, Taiwan.
| | - Alice Y W Chang
- Department of Physiology and Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, 701, Taiwan.
| | - Julie Y H Chan
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, 804, Taiwan.
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 833, Taiwan.
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