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Rapid, Coordinate Inflammatory Responses after Experimental Febrile Status Epilepticus: Implications for Epileptogenesis. eNeuro 2015; 2:eN-NWR-0034-15. [PMID: 26730400 PMCID: PMC4699830 DOI: 10.1523/eneuro.0034-15.2015] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 09/25/2015] [Accepted: 09/28/2015] [Indexed: 11/29/2022] Open
Abstract
Epilepsy is a common neurological disorder with many causes. For temporal lobe epilepsy, antecedent insults are typically found. These risk factors include trauma or history of long fever-associated seizures (febrile status epilepticus) in childhood. Whereas the mechanisms by which such insults promote temporal lobe epilepsy are unknown, an extensive body of work has implicated inflammation and inflammatory mediators in both human and animal models of the disorder. However, direct evidence for an epileptogenic role for inflammation is lacking. Here we capitalized on a model where only a subgroup of insult-experiencing rodents develops epilepsy. We reasoned that if inflammation was important for generating epilepsy, then early inflammation should be more prominent in individuals destined to become epileptic compared with those that will not become epileptic. In addition, the molecular and temporal profile of inflammatory mediators would provide insights into which inflammatory pathways might be involved in the disease process. We examined inflammatory profiles in hippocampus and amygdala of individual rats and correlated them with a concurrent noninvasive, amygdalar magnetic resonance imaging epilepsy-predictive marker. We found significant individual variability in the expression of several important inflammatory mediators, but not in others. Of interest, a higher expression of a subset of hippocampal and amygdalar inflammatory markers within the first few hours following an insult correlated with the epilepsy-predictive signal. These findings suggest that some components of the inflammatory gene network might contribute to the process by which insults promote the development of temporal lobe epilepsy.
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202
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Gershen LD, Zanotti-Fregonara P, Dustin IH, Liow JS, Hirvonen J, Kreisl WC, Jenko KJ, Inati SK, Fujita M, Morse CL, Brouwer C, Hong JS, Pike VW, Zoghbi SS, Innis RB, Theodore WH. Neuroinflammation in Temporal Lobe Epilepsy Measured Using Positron Emission Tomographic Imaging of Translocator Protein. JAMA Neurol 2015; 72:882-8. [PMID: 26052981 DOI: 10.1001/jamaneurol.2015.0941] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
IMPORTANCE Neuroinflammation may play a role in epilepsy. Translocator protein 18 kDa (TSPO), a biomarker of neuroinflammation, is overexpressed on activated microglia and reactive astrocytes. A preliminary positron emission tomographic (PET) imaging study using carbon 11 ([11C])-labeled PBR28 in patients with temporal lobe epilepsy (TLE) found increased TSPO ipsilateral to seizure foci. Full quantitation of TSPO in vivo is needed to detect widespread inflammation in the epileptic brain. OBJECTIVES To determine whether patients with TLE have widespread TSPO overexpression using [11C]PBR28 PET imaging, and to replicate relative ipsilateral TSPO increases in patients with TLE using [11C]PBR28 and another TSPO radioligand, [11C]DPA-713. DESIGN, SETTING, AND PARTICIPANTS In a cohort study from March 2009 through September 2013 at the Clinical Epilepsy Section of the National Institute of Neurological Disorders and Stroke, participants underwent brain PET and a subset had concurrent arterial sampling. Twenty-three patients with TLE and 11 age-matched controls were scanned with [11C]PBR28, and 8 patients and 7 controls were scanned with [11C]DPA-713. Patients with TLE had unilateral temporal seizure foci based on ictal electroencephalography and structural magnetic resonance imaging. Participants with homozygous low-affinity TSPO binding were excluded. MAIN OUTCOMES AND MEASURES The [11C]PBR28 distribution volume (VT) corrected for free fraction (fP) was measured in patients with TLE and controls using FreeSurfer software and T1-weighted magnetic resonance imaging for anatomical localization of bilateral temporal and extratemporal regions. Side-to-side asymmetry in patients with TLE was calculated as the ratio of ipsilateral to contralateral [11C]PBR28 and [11C]DPA-713 standardized uptake values from temporal regions. RESULTS The [11C]PBR28 VT to fp ratio was higher in patients with TLE than in controls for all ipsilateral temporal regions (27%-42%; P < .05) and in contralateral hippocampus, amygdala, and temporal pole (approximately 30%-32%; P < .05). Individually, 12 patients, 10 with mesial temporal sclerosis, had asymmetrically increased hippocampal [11C]PBR28 uptake exceeding the 95% confidence interval of the controls. Binding of [11C]PBR28 was increased significantly in thalamus. Relative [11C]PBR28 and [11C]DPA-713 uptakes were higher ipsilateral than contralateral to seizure foci in patients with TLE ([11C]PBR28: 2%-6%; [11C]DPA-713: 4%-9%). Asymmetry of [11C]DPA-713 was greater than that of [11C]PBR28 (F = 29.4; P = .001). CONCLUSIONS AND RELEVANCE Binding of TSPO is increased both ipsilateral and contralateral to seizure foci in patients with TLE, suggesting ongoing inflammation. Anti-inflammatory therapy may play a role in treating drug-resistant epilepsy.
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Affiliation(s)
- Leah D Gershen
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Paolo Zanotti-Fregonara
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland2University of Bordeaux, Aquitaine Institute for Cognitive and Integrative Neuroscience, National Centre for Scientific Research, Talence, Fran
| | - Irene H Dustin
- Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland
| | - Jeih-San Liow
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Jussi Hirvonen
- Department of Radiology, University of Turku, Turku, Finland
| | - William C Kreisl
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Kimberly J Jenko
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Sara K Inati
- Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland
| | - Masahiro Fujita
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Cheryl L Morse
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Chad Brouwer
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Jinsoo S Hong
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Sami S Zoghbi
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Robert B Innis
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - William H Theodore
- Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland
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203
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Cerebral Response to Peripheral Challenge with a Viral Mimetic. Neurochem Res 2015; 41:144-55. [PMID: 26526143 DOI: 10.1007/s11064-015-1746-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/22/2015] [Accepted: 10/24/2015] [Indexed: 10/22/2022]
Abstract
It has been well established that peripheral inflammation resulting from microbial infections profoundly alters brain function. This review focuses on experimental systems that model cerebral effects of peripheral viral challenge. The most common models employ the induction of the acute phase response via intraperitoneal injection of a viral mimetic, polyinosinic-polycytidylic acid (PIC). The ensuing transient surge of blood-borne inflammatory mediators induces a "mirror" inflammatory response in the brain characterized by the upregulated expression of a plethora of genes encoding cytokines, chemokines and other inflammatory/stress proteins. These inflammatory mediators modify the activity of neuronal networks leading to a constellation of behavioral traits collectively categorized as the sickness behavior. Sickness behavior is an important protective response of the host that has evolved to enhance survival and limit the spread of infections within a population. However, a growing body of clinical data indicates that the activation of inflammatory pathways in the brain may constitute a serious comorbidity factor for neuropathological conditions. Such comorbidity has been demonstrated using the PIC paradigm in experimental models of Alzheimer's disease, prion disease and seizures. Also, prenatal or perinatal PIC challenge has been shown to disrupt normal cerebral development of the offspring resulting in phenotypes consistent with neuropsychiatric disorders, such as schizophrenia and autism. Remarkably, recent studies indicate that mild peripheral PIC challenge may be neuroprotective in stroke. Altogether, the PIC challenge paradigm represents a unique heuristic model to elucidate the immune-to-brain communication pathways and to explore preventive strategies for neuropathological disorders.
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204
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Exposure to prenatal stress has deleterious effects on hippocampal function in a febrile seizure rat model. Brain Res 2015; 1624:506-514. [DOI: 10.1016/j.brainres.2015.07.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 06/29/2015] [Accepted: 07/23/2015] [Indexed: 12/21/2022]
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205
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Pohlmann-Eden B, Aldenkamp A, Baker GA, Brandt C, Cendes F, Coras R, Crocker CE, Helmstaedter C, Jones-Gotman M, Kanner AM, Mazarati A, Mula M, Smith ML, Omisade A, Tellez-Zenteno J, Hermann BP. The relevance of neuropsychiatric symptoms and cognitive problems in new-onset epilepsy - Current knowledge and understanding. Epilepsy Behav 2015; 51:199-209. [PMID: 26291774 DOI: 10.1016/j.yebeh.2015.07.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 07/03/2015] [Indexed: 01/11/2023]
Abstract
Neurobehavioral and cognition problems are highly prevalent in epilepsy, but most research studies to date have not adequately addressed the precise nature of the relationship between these comorbidities and seizures. To address this complex issue and to facilitate collaborative, innovative research in the rising field of neurobehavioral comorbidities and cognition disturbances in new-onset epilepsy, international epilepsy experts met at the 3rd Halifax International Epilepsy Conference & Retreat at White Point, South Shore, Nova Scotia, Canada from September 18 to 20, 2014. This Conference Proceedings provides a summary of the conference proceedings. Specifically, the following topics are discussed: (i) role of comorbidities in epilepsy diagnosis and management, (ii) role of antiepileptic medications in understanding the relationship between epilepsy and neurobehavioral and cognition problems, and (iii) animal data and diagnostic approaches. Evidence to date, though limited, strongly suggests a bidirectional relationship between epilepsy and cognitive and psychiatric comorbidities. In fact, it is likely that seizures and neurobehavioral problems represent different symptoms of a common etiology or network-wide disturbance. As a reflection of this shared network, psychiatric comorbidities and/or cognition problems may actually precede the seizure occurrence and likely get often missed if not screened.
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Affiliation(s)
- B Pohlmann-Eden
- Division of Neurology, Dalhousie University of Halifax, Canada; Brain Repair Center, Dalhousie University of Halifax, Canada.
| | - A Aldenkamp
- Epilepsiecentrum Kempenhaeghe, The Netherlands
| | - G A Baker
- Division of Neurosciences, University of Liverpool, United Kingdom
| | - C Brandt
- Bethel Epilepsy Center, Mara Hospital, Bielefeld, Germany
| | - F Cendes
- Department of Neurology, University of Campinas, São Paulo, Brazil
| | - R Coras
- Department of Neuropathology, University of Erlangen, Germany
| | - C E Crocker
- Division of Neurology, Dalhousie University of Halifax, Canada
| | | | - M Jones-Gotman
- McGill University, Montreal Neurological Institute, Montreal, Canada
| | - A M Kanner
- Epilepsy Center, University of Miami, Miller School of Medicine, USA
| | - A Mazarati
- Children's Discovery and Innovation Institute, D. Geffen School of Medicine at UCLA, Los Angeles, USA
| | - M Mula
- Epilepsy Group, Atkinson Morley Regional Neuroscience Centre, St. George's University Hospitals NHS Foundation Trust and Institute of Medical and Biomedical Sciences St. George's University of London, United Kingdom
| | - M L Smith
- Department of Psychology, University of Toronto, Canada
| | - A Omisade
- Division of Neurology, Dalhousie University of Halifax, Canada
| | | | - B P Hermann
- Department of Neurology, University of Wisconsin School of Medicine and Public Health, Madison, USA
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206
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Berretta S, Heckers S, Benes FM. Searching human brain for mechanisms of psychiatric disorders. Implications for studies on schizophrenia. Schizophr Res 2015; 167:91-7. [PMID: 25458567 PMCID: PMC4427537 DOI: 10.1016/j.schres.2014.10.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 10/10/2014] [Accepted: 10/13/2014] [Indexed: 12/14/2022]
Abstract
In the past 25years, research on the human brain has been providing a clear path toward understanding the pathophysiology of psychiatric illnesses. The successes that have been accrued are matched by significant difficulties identifying and controlling a large number of potential confounding variables. By systematically and effectively accounting for unwanted variance in data from imaging and postmortem human brain studies, meaningful and reliable information regarding the pathophysiology of human brain disorders can be obtained. This perspective paper focuses on postmortem investigations to discuss some of the most challenging sources of variance, including diagnosis, comorbidity, substance abuse and pharmacological treatment, which confound investigations of the human brain.
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Affiliation(s)
- Sabina Berretta
- Translational Neuroscience Laboratory, McLean Hospital, 115 Mill St., Belmont, MA 02478, USA; Department of Psychiatry, Harvard Medical School, 25 Shattuck St., Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, 25 Shattuck St., Boston, MA 02115, USA.
| | - Stephan Heckers
- Department of Psychiatry, Vanderbilt University. 161 21st Ave S. #T1217 Nashville, TN, USA
| | - Francine M. Benes
- Dept. of Psychiatry, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA,Program in Neuroscience, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA,Program in Structural and Molecular Neuroscience, 115 Mill St. Belmont MA, 02478, USA
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207
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Modulatory effects of inosine, guanosine and uridine on lipopolysaccharide-evoked increase in spike-wave discharge activity in Wistar Albino Glaxo/Rijswijk rats. Brain Res Bull 2015; 118:46-57. [DOI: 10.1016/j.brainresbull.2015.09.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 09/05/2015] [Accepted: 09/07/2015] [Indexed: 12/20/2022]
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208
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Jensen FE. Developmental factors in the pathogenesis of neonatal seizures. JOURNAL OF PEDIATRIC NEUROLOGY 2015; 7:5-12. [PMID: 20191097 DOI: 10.3233/jpn-2009-0270] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Neonatal seizures are inherently different from seizures in the child and the adult. The phenotype, often exhibiting electroclinical dissociation, is unique: neonatal seizures can be refractory to antiepileptic drugs otherwise effect for older patients. Recent experimental and human-based research reveals that the mechanism of neonatal seizures, as well as their long-term sequelae on later brain development, appears to involve a large number of age-specific factors. These observations help explain the resistance of neonatal seizures to conventional therapy as well as identify potential areas of risk for later neurocognitive development. Emerging targets from this research may suggest new therapies for this unique population of patients.
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Affiliation(s)
- Frances E Jensen
- Department of Neurology, Children's Hospital, and Program in Neurobiology, Harvard Medical School, Boston, MA, USA
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209
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Lin Q, Wang X. Differences in epileptic symptoms depending on the type of autoimmune-mediated limbic encephalitis. Expert Rev Clin Immunol 2015; 11:897-910. [PMID: 26163176 DOI: 10.1586/1744666x.2015.1055253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Limbic encephalitis (LE) is an inflammatory disease of the central nervous system that is characterized by the selective involvement of limbic structures. The clinical manifestations of LE include the acute or sub-acute onset of recent memory disorders, mental disorders and seizures. Autoimmune-mediated LE is a major type of non-infectious LE; seizure is a hallmark of this type of LE. The treatment of epilepsy, which is a key factor that affects the prognosis of LE patients, warrants special attention. Understanding the characteristics of epilepsy caused by autoimmune-mediated LE and providing the appropriate treatment will help to improve patients' outcomes. In this article, we extensively review the literature related to autoimmune-mediated LE epidemiology, mechanisms, characteristics and seizure frequency and onset, and we discuss the possible diagnosis and treatment of this disease.
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Affiliation(s)
- Qingxia Lin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
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210
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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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211
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Tao AF, Xu ZH, Chen B, Wang Y, Wu XH, Zhang J, Tang YS, Xu CL, Zhao HW, Hu WW, Shi LY, Zhang SH, Chen Z. The Pro-inflammatory Cytokine Interleukin-1β is a Key Regulatory Factor for the Postictal Suppression in Mice. CNS Neurosci Ther 2015; 21:642-50. [PMID: 26096304 DOI: 10.1111/cns.12416] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 05/12/2015] [Accepted: 05/13/2015] [Indexed: 01/18/2023] Open
Abstract
AIMS The postictal suppression (PS) is a common and important period following an epileptic seizure but has not been well studied. This study was designed to determine whether interleukin-1β (IL-1β) is involved in the PS. METHODS The effects of IL-1β on the PS were tested in three independent seizure models induced by hippocampal kindling, maximal electroshock seizure (MES), and 4-aminopyridine, respectively. RESULTS IL-1R1 knockout or IL-1RA enhanced the seizure refractory phenomenon without influencing the baseline seizure threshold in intermittent MES model. IL-1β attenuated the seizure refractory phenomenon without affecting the severity of the preceding seizures in hippocampal kindling model, while IL-1RA enhanced it. Besides, IL-1β reduced the postictal EEG suppression period, while IL-1RA prolonged it. And IL-1β showed no further effect on the postictal EEG suppression and seizure refractory phenomenon in IL-1R1 knockout mice. In addition, 30 min after intrahippocampal injection of 4-aminopyridine, IL-1β increased the incidence of SE, while IL-1RA prolonged the intervals between recurrent seizures. CONCLUSIONS This study provides the first direct evidence that IL-1β is key regulatory factor for the PS, and its receptor IL-1R1 may be a potential target for adjuvant treatment of postictal problems.
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Affiliation(s)
- An-Feng Tao
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zheng-Hao Xu
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.,College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Bin Chen
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yi Wang
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiao-Hua Wu
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jing Zhang
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yang-Shun Tang
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ceng-Lin Xu
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Hua-Wei Zhao
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Wei-Wei Hu
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Li-Yun Shi
- Department of Basic Medical Science, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Shi-Hong Zhang
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhong Chen
- Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China and Zhejiang Province Key Laboratory of Neurobiology, College of Pharmaceutical Sciences, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
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Fukuda M, Ito M, Yano Y, Takahashi H, Motoie R, Yano A, Suzuki Y, Ishii E. Postnatal interleukin-1β administration after experimental prolonged febrile seizures enhances epileptogenesis in adulthood. Metab Brain Dis 2015; 30:813-9. [PMID: 25575695 DOI: 10.1007/s11011-014-9648-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 12/29/2014] [Indexed: 01/31/2023]
Abstract
It remains unclear whether prolonged febrile seizures (pFS) in childhood facilitate mesial temporal lobe epilepsy (MTLE) in adulthood. Interleukin (IL)-1β is associated with seizures in children and immature animal models. Here, we use a rat model of pFS to study the effects of IL-1β on adult epileptogenesis, hippocampal damage, and cognition. We produced prolonged hyperthermia-induced seizures on postnatal days (P) 10-11 and administered IL-1β or saline intranasally immediately after the seizures. Motor and cognitive functions were assessed at P85 using rotarod and passive avoidance tests. Electroencephalogram recordings were conducted at P90 and P120. Hippocampal CA1 and CA3 neurons and gliosis were quantified at the end of the experiment. Spontaneous seizure incidence was significantly greater in rats that had received IL-1β than in those that had received saline or those without hyperthermia-induced seizures (p < 0.05). Seizure frequency did not differ significantly between the three groups and no motor deficits were observed. Passive avoidance learning was impaired in rats that received IL-1β compared with controls (p < 0.05), but was not different from that in rats that received saline. Hippocampal cell numbers and gliosis did not differ between the three groups. These results indicate that neuronal loss and gliosis are not prerequisites for the epileptogenic process that follows pFS. Our results suggest that infantile pFS combined with IL-1β overproduction can enhance adulthood epileptogenesis, and might contribute to the development of MTLE.
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Affiliation(s)
- Mitsumasa Fukuda
- Department of Pediatrics, Ehime University Graduate School of Medicine, 454 Shitsukawa, Toon, Ehime, 791-0295, Japan,
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Kong H, Yin F, He F, Omran A, Li L, Wu T, Wang Y, Peng J. The Effect of miR-132, miR-146a, and miR-155 on MRP8/TLR4-Induced Astrocyte-Related Inflammation. J Mol Neurosci 2015; 57:28-37. [PMID: 25957996 DOI: 10.1007/s12031-015-0574-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 04/28/2015] [Indexed: 01/20/2023]
Abstract
Astrocyte activation, associated with the release of pro-inflammatory cytokines interleukin 1-β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α), is a hallmark of multiple brain diseases, including mesial temporal lobe epilepsy. In recent years, several microRNAs have emerged as important controllers of Toll-like receptor (TLR) signaling. In this study, we investigated the effect of miR-132, miR-146a, and miR-155 on myeloid-related protein-8 (MRP8) induced astrocyte-related inflammation. Using quantitative polymerase chain reaction (qPCR) and western blot, we found clear upregulation of TLR4 and downstream inflammatory cytokines, along with dysregulation of miR-132, miR-146a, and miR-155 in in vitro astrocytes after exposing them to different concentrations of MRP8. In addition, we focused on the effect of miR-132 on astrocyte-related inflammation induced by MRP8 via lentiviral infection then evaluated the expression of its possible target genes: acetylcholinesterase (AChE) and interleukin-1 receptor-associated kinase (IRAK4). Our results show that miR-132 is a negative feedback regulator of IL-1β and IL-6, but not TNF-α, by targeting IRAK4. Together, our findings demonstrate the novel role of TLR4-related microRNAs, especially miR-132, in the regulation of MRP8-induced astrocyte activation and highlight the importance of miR-132 in the modulation of innate immune response induced by endogenous ligands in neurological diseases.
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Affiliation(s)
- Huimin Kong
- Department of Pediatrics, Xiangya Hospital of Central South University, No. 87 Xiangya Road, Changsha, Hunan, 410008, China
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214
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Suleiman J, Dale RC. The recognition and treatment of autoimmune epilepsy in children. Dev Med Child Neurol 2015; 57:431-40. [PMID: 25483277 DOI: 10.1111/dmcn.12647] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/31/2014] [Indexed: 01/07/2023]
Abstract
There is emerging interest in autoimmune epilepsy, which represents a small but potentially treatable form of epilepsy. Most insights into autoimmune epilepsy derive from the recent descriptions of autoimmune encephalitis that takes two general forms: a focal encephalitis (such as limbic) or a diffuse encephalitis (such as anti-N-methyl-D-aspartate receptor [NMDAR] encephalitis). The features of autoimmune epilepsy include acute or subacute onset of seizures, usually in the context of encephalopathy, and inflammation of the central nervous system on testing cerebrospinal fluid or magnetic resonance imaging. Neuronal antibodies associated with autoimmune encephalitis and seizures in children include NMDAR, voltage-gated potassium channel complex, glycine receptor, γ-Aminobutyric acid type A receptor (GABA(A)R), γ-Aminobutyric acid type B receptor (GABA(B)R), and glutamic acid decarboxylase antibodies. These antibodies support the diagnosis of autoimmune epilepsy, but are not essential for diagnosis. When autoimmune epilepsy is suspected, first-line immune therapy with corticosteroids in addition to intravenous immunoglobulin or plasma exchange should be considered. Second-line therapy with rituximab or cyclophosphamide can be considered if the syndrome is severe. A response to immune therapy supports the diagnosis of autoimmune epilepsy. Neuronal antibodies are increasingly found in patients with focal epilepsy of unknown cause who do not have 'encephalitis'. Recent epidemiological studies support the link between epilepsy and autoimmune diseases. Future studies need to define the spectrum of autoimmune epilepsy and focus on early identification and treatment.
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Affiliation(s)
- Jehan Suleiman
- Department of Paediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates; Paediatrics and Child Health Discipline, Clinical School, The Children's Hospital at Westmead, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
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215
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Blednov YA, Benavidez JM, Black M, Mayfield J, Harris RA. Role of interleukin-1 receptor signaling in the behavioral effects of ethanol and benzodiazepines. Neuropharmacology 2015; 95:309-20. [PMID: 25839897 DOI: 10.1016/j.neuropharm.2015.03.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 02/10/2015] [Accepted: 03/16/2015] [Indexed: 12/20/2022]
Abstract
Gene expression studies identified the interleukin-1 receptor type I (IL-1R1) as part of a pathway associated with a genetic predisposition to high alcohol consumption, and lack of the endogenous IL-1 receptor antagonist (IL-1ra) strongly reduced ethanol intake in mice. Here, we compared ethanol-mediated behaviors in mice lacking Il1rn or Il1r1. Deletion of Il1rn (the gene encoding IL-1ra) increases sensitivity to the sedative/hypnotic effects of ethanol and flurazepam and reduces severity of acute ethanol withdrawal. Conversely, deletion of Il1r1 (the gene encoding the IL-1 receptor type I, IL-1R1) reduces sensitivity to the sedative effects of ethanol and flurazepam and increases the severity of acute ethanol withdrawal. The sedative effects of ketamine and pentobarbital were not altered in the knockout (KO) strains. Ethanol intake and preference were not changed in mice lacking Il1r1 in three different tests of ethanol consumption. Recovery from ethanol-induced motor incoordination was only altered in female mice lacking Il1r1. Mice lacking Il1rn (but not Il1r1) showed increased ethanol clearance and decreased ethanol-induced conditioned taste aversion. The increased ethanol- and flurazepam-induced sedation in Il1rn KO mice was decreased by administration of IL-1ra (Kineret), and pre-treatment with Kineret also restored the severity of acute ethanol withdrawal. Ethanol-induced sedation and withdrawal severity were changed in opposite directions in the null mutants, indicating that these responses are likely regulated by IL-1R1 signaling, whereas ethanol intake and preference do not appear to be solely regulated by this pathway.
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Affiliation(s)
- Yuri A Blednov
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, USA
| | - Jillian M Benavidez
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, USA
| | - Mendy Black
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, USA
| | - Jody Mayfield
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, USA
| | - R Adron Harris
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, USA.
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216
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Citraro R, Leo A, Marra R, De Sarro G, Russo E. Antiepileptogenic effects of the selective COX-2 inhibitor etoricoxib, on the development of spontaneous absence seizures in WAG/Rij rats. Brain Res Bull 2015; 113:1-7. [DOI: 10.1016/j.brainresbull.2015.02.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 02/09/2015] [Accepted: 02/13/2015] [Indexed: 11/25/2022]
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217
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Bedner P, Dupper A, Hüttmann K, Müller J, Herde MK, Dublin P, Deshpande T, Schramm J, Häussler U, Haas CA, Henneberger C, Theis M, Steinhäuser C. Astrocyte uncoupling as a cause of human temporal lobe epilepsy. Brain 2015; 138:1208-22. [PMID: 25765328 DOI: 10.1093/brain/awv067] [Citation(s) in RCA: 209] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 01/13/2015] [Indexed: 12/20/2022] Open
Abstract
Glial cells are now recognized as active communication partners in the central nervous system, and this new perspective has rekindled the question of their role in pathology. In the present study we analysed functional properties of astrocytes in hippocampal specimens from patients with mesial temporal lobe epilepsy without (n = 44) and with sclerosis (n = 75) combining patch clamp recording, K(+) concentration analysis, electroencephalography/video-monitoring, and fate mapping analysis. We found that the hippocampus of patients with mesial temporal lobe epilepsy with sclerosis is completely devoid of bona fide astrocytes and gap junction coupling, whereas coupled astrocytes were abundantly present in non-sclerotic specimens. To decide whether these glial changes represent cause or effect of mesial temporal lobe epilepsy with sclerosis, we developed a mouse model that reproduced key features of human mesial temporal lobe epilepsy with sclerosis. In this model, uncoupling impaired K(+) buffering and temporally preceded apoptotic neuronal death and the generation of spontaneous seizures. Uncoupling was induced through intraperitoneal injection of lipopolysaccharide, prevented in Toll-like receptor4 knockout mice and reproduced in situ through acute cytokine or lipopolysaccharide incubation. Fate mapping confirmed that in the course of mesial temporal lobe epilepsy with sclerosis, astrocytes acquire an atypical functional phenotype and lose coupling. These data suggest that astrocyte dysfunction might be a prime cause of mesial temporal lobe epilepsy with sclerosis and identify novel targets for anti-epileptogenic therapeutic intervention.
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Affiliation(s)
- Peter Bedner
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
| | - Alexander Dupper
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
| | - Kerstin Hüttmann
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
| | - Julia Müller
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
| | - Michel K Herde
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
| | - Pavel Dublin
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany Current address: Institute of Neurobiology, University of Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Tushar Deshpande
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
| | - Johannes Schramm
- 2 Department of Neurosurgery, Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
| | - Ute Häussler
- 3 Experimental Epilepsy Research, Department of Neurosurgery, University Hospital Freiburg, 79106 Freiburg, Germany
| | - Carola A Haas
- 3 Experimental Epilepsy Research, Department of Neurosurgery, University Hospital Freiburg, 79106 Freiburg, Germany
| | - Christian Henneberger
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany 4 UCL Institute of Neurology, UCL, London WC1N 3BG, UK
| | - Martin Theis
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
| | - Christian Steinhäuser
- 1 Institute of Cellular Neurosciences and Medical Faculty, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany
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218
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Vezzani A. Anti-inflammatory drugs in epilepsy: does it impact epileptogenesis? Expert Opin Drug Saf 2015; 14:583-92. [DOI: 10.1517/14740338.2015.1010508] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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219
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Crunelli V, Carmignoto G, Steinhäuser C. Novel astrocyte targets: new avenues for the therapeutic treatment of epilepsy. Neuroscientist 2015; 21:62-83. [PMID: 24609207 PMCID: PMC4361461 DOI: 10.1177/1073858414523320] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
During the last 20 years, it has been well established that a finely tuned, continuous crosstalk between neurons and astrocytes not only critically modulates physiological brain functions but also underlies many neurological diseases. In particular, this novel way of interpreting brain activity is markedly influencing our current knowledge of epilepsy, prompting a re-evaluation of old findings and guiding novel experimentation. Here, we review recent studies that have unraveled novel and unique contributions of astrocytes to the generation and spread of convulsive and nonconvulsive seizures and epileptiform activity. The emerging scenario advocates an overall framework in which a dynamic and reciprocal interplay among astrocytic and neuronal ensembles is fundamental for a fuller understanding of epilepsy. In turn, this offers novel astrocytic targets for the development of those really novel chemical entities for the control of convulsive and nonconvulsive seizures that have been acknowledged as a key priority in the management of epilepsy.
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Affiliation(s)
- Vincenzo Crunelli
- Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, UK
| | - Giorgio Carmignoto
- Centro Nazionale della Ricerca, Neuroscience Institute and Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
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220
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Johnson MR, Behmoaras J, Bottolo L, Krishnan ML, Pernhorst K, Santoscoy PLM, Rossetti T, Speed D, Srivastava PK, Chadeau-Hyam M, Hajji N, Dabrowska A, Rotival M, Razzaghi B, Kovac S, Wanisch K, Grillo FW, Slaviero A, Langley SR, Shkura K, Roncon P, De T, Mattheisen M, Niehusmann P, O'Brien TJ, Petrovski S, von Lehe M, Hoffmann P, Eriksson J, Coffey AJ, Cichon S, Walker M, Simonato M, Danis B, Mazzuferi M, Foerch P, Schoch S, De Paola V, Kaminski RM, Cunliffe VT, Becker AJ, Petretto E. Systems genetics identifies Sestrin 3 as a regulator of a proconvulsant gene network in human epileptic hippocampus. Nat Commun 2015; 6:6031. [PMID: 25615886 DOI: 10.1038/ncomms7031] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 12/04/2014] [Indexed: 01/20/2023] Open
Abstract
Gene-regulatory network analysis is a powerful approach to elucidate the molecular processes and pathways underlying complex disease. Here we employ systems genetics approaches to characterize the genetic regulation of pathophysiological pathways in human temporal lobe epilepsy (TLE). Using surgically acquired hippocampi from 129 TLE patients, we identify a gene-regulatory network genetically associated with epilepsy that contains a specialized, highly expressed transcriptional module encoding proconvulsive cytokines and Toll-like receptor signalling genes. RNA sequencing analysis in a mouse model of TLE using 100 epileptic and 100 control hippocampi shows the proconvulsive module is preserved across-species, specific to the epileptic hippocampus and upregulated in chronic epilepsy. In the TLE patients, we map the trans-acting genetic control of this proconvulsive module to Sestrin 3 (SESN3), and demonstrate that SESN3 positively regulates the module in macrophages, microglia and neurons. Morpholino-mediated Sesn3 knockdown in zebrafish confirms the regulation of the transcriptional module, and attenuates chemically induced behavioural seizures in vivo.
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Affiliation(s)
- Michael R Johnson
- Division of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Burlington Danes Building, London W12 0NN, UK
| | - Jacques Behmoaras
- Centre for Complement and Inflammation Research, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Leonardo Bottolo
- Department of Mathematics, Imperial College London, 180 Queen's Gate, London SW7 2AZ, UK
| | - Michelle L Krishnan
- Centre for the Developing Brain, Department of Perinatal Imaging and Health, St Thomas' Hospital, King's College London, London SE1 7EH, UK
| | - Katharina Pernhorst
- Section of Translational Epileptology, Department of Neuropathology, University of Bonn, Sigmund Freud Street 25, Bonn D-53127, Germany
| | - Paola L Meza Santoscoy
- Department of Biomedical Science, Bateson Centre, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Tiziana Rossetti
- Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Doug Speed
- UCL Genetics Institute, University College London, Gower Street, London WC1E 6BT, UK
| | - Prashant K Srivastava
- Division of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Burlington Danes Building, London W12 0NN, UK.,Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Marc Chadeau-Hyam
- Department of Epidemiology and Biostatistics, School of Public Health, MRC/PHE Centre for Environment and Health, Imperial College London, St Mary's Hospital, Norfolk Place, W21PG London, UK
| | - Nabil Hajji
- Department of Medicine, Centre for Pharmacology and Therapeutics, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Aleksandra Dabrowska
- Department of Medicine, Centre for Pharmacology and Therapeutics, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Maxime Rotival
- Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Banafsheh Razzaghi
- Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Stjepana Kovac
- Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Klaus Wanisch
- Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Federico W Grillo
- Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Anna Slaviero
- Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Sarah R Langley
- Division of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Burlington Danes Building, London W12 0NN, UK.,Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Kirill Shkura
- Division of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Burlington Danes Building, London W12 0NN, UK.,Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Paolo Roncon
- Department of Medical Sciences, Section of Pharmacology and Neuroscience Center, University of Ferrara, 44121 Ferrara, Italy.,National Institute of Neuroscience, 44121 Ferrara, Italy
| | - Tisham De
- Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Manuel Mattheisen
- Department of Genomics, Life and Brain Center, University of Bonn, D-53127 Bonn, Germany.,Institute of Human Genetics, University of Bonn, D-53127 Bonn, Germany.,Institute for Genomic Mathematics, University of Bonn, D-53127 Bonn, Germany
| | - Pitt Niehusmann
- Section of Translational Epileptology, Department of Neuropathology, University of Bonn, Sigmund Freud Street 25, Bonn D-53127, Germany
| | - Terence J O'Brien
- Department of Medicine, RMH, University of Melbourne, Royal Melbourne Hospital, Royal Parade, Parkville, Victoria 3050, Australia
| | - Slave Petrovski
- Department of Neurology, Royal Melbourne Hospital, Melbourne, Parkville, Victoria 3050, Australia
| | - Marec von Lehe
- Department of Neurosurgery, University of Bonn Medical Center, Sigmund-Freud-Strasse 25, 53105 Bonn, Germany
| | - Per Hoffmann
- Institute of Human Genetics, University of Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany.,Department of Biomedicine, University of Basel, Hebelstrasse 20, 4056 Basel, Switzerland
| | - Johan Eriksson
- Folkhälsan Research Centre, Topeliusgatan 20, 00250 Helsinki, Finland.,Helsinki University Central Hospital, Unit of General Practice, Haartmaninkatu 4, Helsinki 00290, Finland.,Department of General Practice and Primary Health Care, University of Helsinki, 407, PO Box 20, Tukholmankatu 8 B, Helsinki 00014, Finland
| | - Alison J Coffey
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Sven Cichon
- Institute of Human Genetics, University of Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany.,Department of Biomedicine, University of Basel, Hebelstrasse 20, 4056 Basel, Switzerland
| | - Matthew Walker
- Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Michele Simonato
- Department of Medical Sciences, Section of Pharmacology and Neuroscience Center, University of Ferrara, 44121 Ferrara, Italy.,National Institute of Neuroscience, 44121 Ferrara, Italy.,Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, 44121 Ferrara, Italy
| | - Bénédicte Danis
- Neuroscience TA, UCB Biopharma SPRL, Avenue de l'industrie, R9, B-1420 Braine l'Alleud, Belgium
| | - Manuela Mazzuferi
- Neuroscience TA, UCB Biopharma SPRL, Avenue de l'industrie, R9, B-1420 Braine l'Alleud, Belgium
| | - Patrik Foerch
- Neuroscience TA, UCB Biopharma SPRL, Avenue de l'industrie, R9, B-1420 Braine l'Alleud, Belgium
| | - Susanne Schoch
- Section of Translational Epileptology, Department of Neuropathology, University of Bonn, Sigmund Freud Street 25, Bonn D-53127, Germany.,Department of Epileptology, University of Bonn Medical Center, Sigmund-Freud-Strasse 25, Bonn D-53127, Germany
| | - Vincenzo De Paola
- Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Rafal M Kaminski
- Neuroscience TA, UCB Biopharma SPRL, Avenue de l'industrie, R9, B-1420 Braine l'Alleud, Belgium
| | - Vincent T Cunliffe
- Department of Biomedical Science, Bateson Centre, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Albert J Becker
- Section of Translational Epileptology, Department of Neuropathology, University of Bonn, Sigmund Freud Street 25, Bonn D-53127, Germany
| | - Enrico Petretto
- Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK.,Duke-NUS Graduate Medical School, 8 College Road, Singapore 169857, Singapore
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221
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Vagal nerve stimulation blocks interleukin 6-dependent synaptic hyperexcitability induced by lipopolysaccharide-induced acute stress in the rodent prefrontal cortex. Brain Behav Immun 2015; 43:149-58. [PMID: 25128387 PMCID: PMC4727901 DOI: 10.1016/j.bbi.2014.07.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 07/29/2014] [Accepted: 07/29/2014] [Indexed: 01/24/2023] Open
Abstract
The ratio between synaptic inhibition and excitation (sI/E) is a critical factor in the pathophysiology of neuropsychiatric disease. We recently described a stress-induced interleukin-6 dependent mechanism leading to a decrease in sI/E in the rodent temporal cortex. The aim of the present study was to determine whether a similar mechanism takes place in the prefrontal cortex, and to elaborate strategies to prevent or attenuate it. We used aseptic inflammation (single acute injections of lipopolysaccharide, LPS, 10mg/kg) as stress model, and patch-clamp recording on a prefrontal cortical slice preparation from wild-type rat and mice, as well as from transgenic mice in which the inhibitor of IL-6 trans-signaling sgp130Fc was produced in a brain-specific fashion (sgp130Fc mice). The anti-inflammatory reflex was activated either by vagal nerve stimulation or peripheral administration of the nicotinic α7 receptor agonist PHA543613. We found that the IL-6-dependent reduction in prefrontal cortex synaptic inhibition was blocked in sgp130Fc mice, or - in wild-type animals - upon application sgp130Fc. Similar results were obtained by activating the "anti-inflammatory reflex" - a neural circuit regulating peripheral immune response - by stimulation of the vagal nerve or through peripheral administration of the α7 nicotinic receptor agonist PHA543613. Our results indicate that the prefrontal cortex is an important potential target of IL-6 mediated trans-signaling, and suggest a potential new avenue in the treatment of a large class of hyperexcitable neuropsychiatric conditions, including epilepsy, schizophrenic psychoses, anxiety disorders, autism spectrum disorders, and depression.
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222
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Matin N, Tabatabaie O, Falsaperla R, Lubrano R, Pavone P, Mahmood F, Gullotta M, Serra A, Mauro PD, Cocuzza S, Vitaliti G. Epilepsy and innate immune system: A possible immunogenic predisposition and related therapeutic implications. Hum Vaccin Immunother 2015; 11:2021-9. [PMID: 26260962 PMCID: PMC4635700 DOI: 10.1080/21645515.2015.1034921] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 03/09/2015] [Accepted: 03/23/2015] [Indexed: 12/16/2022] Open
Abstract
Recent experimental studies and pathological analyses of patient brain tissue samples with refractory epilepsy suggest that inflammatory processes and neuroinflammation plays a key-role in the etiopathology of epilepsy and convulsive disorders. These inflammatory processes lead to the secretion of pro-inflammatory cytokines responsible for blood-brain-barrier disruption and involvement of resident immune cells in the inflammation pathway, occurring within the Central Nervous System (CNS). These elements are produced through activation of Toll-Like Receptors (TLRs) by exogenous and endogenous ligands thereby increasing expression of cytokines and co-stimulatory molecules through the activation of TLRs 2, 3, 4, and 9 as reported in murine studies.It has been demonstrated that IL-1β intracellular signaling and cascade is able to alter the neuronal excitability without cell loss. The activation of the IL-1β/ IL-1β R axis is strictly linked to the secretion of the intracellular protein MyD88, which interacts with other cell surface receptors, such as TLR4 during pathogenic recognition. Furthermore, TLR-signaling pathways are able to recognize molecules released from damaged tissues, such as damage-associated molecular patterns/proteins (DAMPs). Among these molecules, High-mobility group box-1 (HMGB1) is a component of chromatin that is passively released from necrotic cells and actively released by cells that are subject to profound stress. Moreover, recent studies have described models of epilepsy induced by the administration of bicuculline and kainic acid that highlight the nature of HMGB1-TLR4 interactions, their intracellular signaling pathway as well as their role in ictiogenesis and epileptic recurrence.The aim of our review is to focus on different branches of innate immunity and their role in epilepsy, emphasizing the role of immune related molecules in epileptogenesis and highlighting the research implications for novel therapeutic strategies.
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Affiliation(s)
- Nassim Matin
- Tehran University of Medical Sciences; Tehran, Iran
| | | | - Raffaele Falsaperla
- Pediatrics Operative Unit; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
| | - Riccardo Lubrano
- Paediatric Department; Paediatric Nephrology Operative Unit of the Sapienza University of Rome; Rome, Italy
| | - Piero Pavone
- Pediatrics Operative Unit; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
| | - Fahad Mahmood
- University Hospital of North Staffordshire; Stoke-on-Trent, UK
| | - Melissa Gullotta
- University of Medical Science; University of Catania; Catania, Italy
| | - Agostino Serra
- ENT Department G.F. Ingrassia; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
| | - Paola Di Mauro
- ENT Department G.F. Ingrassia; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
| | - Salvatore Cocuzza
- ENT Department G.F. Ingrassia; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
| | - Giovanna Vitaliti
- Pediatrics Operative Unit; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
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223
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Immune System Related Markers: Changes in childhood Neuropsychiatry Disorders Cause and Consequence. ACTA ACUST UNITED AC 2015. [DOI: 10.1007/978-3-319-13602-8_9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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224
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Abstract
Several epidemiological studies suggest a possible involvement of viral infection in the development of epilepsy. While recent research from in vitro studies increasingly supports the role of herpes simplex virus type 1 (HSV-1) in the pathogenesis of epilepsy, little is known about the role of other viral infections such as influenza. Using data from the Clinical Practice Research Datalink (CPRD), we conducted a matched case-control analysis to assess the association between GP-diagnosed influenza infections and the risk of developing an incident diagnosis of epilepsy. During the study period 11 244 incident epilepsy cases and 44 976 matched control patients were identified. Prior exposure to influenza was reported in 7·5% of epilepsy cases and 6·7% of controls [adjusted odds ratio (aOR) 1·12, 95% confidence interval (CI) 1·03-1·22]. Prior history of 'complicated influenza', i.e. influenza associated with a possible super-infection, was associated with a slightly increased epilepsy risk (aOR 1·64, 95% CI 1·10-2·46), particularly if recorded within the 2 months preceding the epilepsy diagnosis (aOR 6·03, 95% CI 1·10-33·2). Our findings suggest that prior influenza exposure does not appear to materially alter the risk of developing epilepsy. By contrast, influenza episodes accompanied by complications were associated with a slightly increased epilepsy risk.
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225
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Meng XF, Tan L, Tan MS, Jiang T, Tan CC, Li MM, Wang HF, Yu JT. Inhibition of the NLRP3 inflammasome provides neuroprotection in rats following amygdala kindling-induced status epilepticus. J Neuroinflammation 2014; 11:212. [PMID: 25516224 PMCID: PMC4275944 DOI: 10.1186/s12974-014-0212-5] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 12/02/2014] [Indexed: 01/14/2023] Open
Abstract
Background NLRP3 inflammasome is proposed to regulate inflammation in several neurological diseases, but its role in epilepsy remains largely unknown. This study aimed to investigate the role of the NLRP3 inflammasome in neuroinflammation, spontaneous recurrent seizures (SRS) and hippocampal neuronal loss in rat brain following amygdala kindling-induced status epilepticus (SE). Methods We detected the protein levels of IL-1β and NLRP3 inflammasome components by Western blot in the hippocampus of shams and SE rats at different time points following SE. To further examine whether the activation of the NLRP3 inflammasome contributes to SE-associated neuronal damage, we employed a nonviral strategy to knock down NLRP3 and caspase-1 expression in brain before undergoing SE. Proinflammatory cytokine levels and hippocampal neuronal loss were evaluated at 12 hours and at 6 weeks following SE respectively in these NLRP3 and caspase-1 deficient rats. Meanwhile, SRS occurrence was evaluated through a 4-week video recording started 2 weeks after SE in these NLRP3 and caspase-1 deficient rats. Results IL-1β levels and NLRP3 inflammasome components levels dramatically increased at 3 hours after SE, and reached a maximum at 12 hours after SE compared with the control group. Knock down of NLRP3 or caspase-1 decreased the levels of IL-1β and IL-18 at 12 hours after SE, which was accompanied by a significant suppression in the development and severity of SRS during the chronic epileptic phase. Meanwhile, knock down of NLRP3 or caspase-1 led to a remarkable reduction of hippocampal neuronal loss in the CA1 and CA3 area of the hippocampus at 6 weeks after SE. Conclusions Our study provides the first evidence that the NLRP3 inflammasome was significantly up-regulated following SE. More importantly, we show that inhibition of the NLRP3 inflammasome provides neuroprotection in rats following SE. These findings suggest that NLRP3 may represent a potential target for the treatment of epileptogenesis Electronic supplementary material The online version of this article (doi:10.1186/s12974-014-0212-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xiang-Fei Meng
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China.
| | - Lan Tan
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China. .,Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing, PR China. .,Department of Neurology, Qingdao Municipal Hospital, College of Medicine and Pharmaceutics, Ocean University of China, Qingdao, PR China.
| | - Meng-Shan Tan
- Department of Neurology, Qingdao Municipal Hospital, College of Medicine and Pharmaceutics, Ocean University of China, Qingdao, PR China.
| | - Teng Jiang
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, PR China.
| | - Chen-Chen Tan
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China.
| | - Meng-Meng Li
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China.
| | - Hui-Fu Wang
- Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing, PR China.
| | - Jin-Tai Yu
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China. .,Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing, PR China. .,Department of Neurology, Memory and Aging Center, University of California, San Francisco, CA, USA.
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226
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Gruol DL. IL-6 regulation of synaptic function in the CNS. Neuropharmacology 2014; 96:42-54. [PMID: 25445486 DOI: 10.1016/j.neuropharm.2014.10.023] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 10/23/2014] [Accepted: 10/24/2014] [Indexed: 12/20/2022]
Abstract
A growing body of evidence supports a role for glial-produced neuroimmune factors, including the cytokine IL-6, in CNS physiology and pathology. CNS expression of IL-6 has been documented in the normal CNS at low levels and at elevated levels in several neurodegenerative or psychiatric disease states as well as in CNS infection and injury. The altered CNS function associated with these conditions raises the possibility that IL-6 has neuronal or synaptic actions. Studies in in vitro and in vivo models confirmed this possibility and showed that IL-6 can regulate a number of important neuronal and synaptic functions including synaptic transmission and synaptic plasticity, an important cellular mechanism of memory and learning. Behavioral studies in animal models provided further evidence of an important role for IL-6 as a regulator of CNS pathways that are critical to cognitive function. This review summarizes studies that have lead to our current state of knowledge. In spite of the progress that has been made, there is a need for a greater understanding of the physiological and pathophysiological actions of IL-6 in the CNS, the mechanisms underlying these actions, conditions that induce production of IL-6 in the CNS and therapeutic strategies that could ameliorate or promote IL-6 actions. This article is part of a Special Issue entitled 'Neuroimmunology and Synaptic Function'.
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Affiliation(s)
- Donna L Gruol
- Molecular and Cellular Neuroscience Department, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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227
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Falsaperla R, Pavone P, Miceli Sopo S, Mahmood F, Scalia F, Corsello G, Lubrano R, Vitaliti G. Epileptic seizures as a manifestation of cow's milk allergy: a studied relationship and description of our pediatric experience. Expert Rev Clin Immunol 2014; 10:1597-609. [PMID: 25394911 DOI: 10.1586/1744666x.2014.977259] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Adverse reactions after ingestion of cow's milk proteins can occur at any age, from birth and even amongst exclusively breast-fed infants, although not all of these are hypersensitivity reactions. The most common presentations related to cow's milk protein allergy are skin reactions, failure to thrive, anaphylaxis as well as gastrointestinal and respiratory disorders. In addition, several cases of cow's milk protein allergy in the literature have documented neurological involvement, manifesting with convulsive seizures in children. This may be due to CNS spread of a peripheral inflammatory response. Furthermore, there is evidence that pro-inflammatory cytokines are responsible for disrupting the blood-brain barrier, causing focal CNS inflammation thereby triggering seizures, although further studies are needed to clarify the pathogenic relationship between atopy and its neurological manifestations. This review aims to analyze current published data on the link between cow's milk protein allergy and epileptic events, highlighting scientific evidence for any potential pathogenic mechanism and describing our clinical experience in pediatrics.
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Affiliation(s)
- Raffaele Falsaperla
- Paediatric Acute and Emergency Department and Operative Unit, Policlinico-Vittorio Emanuele University Hospital, University of Catania, Via Plebiscito n. 628, 95100, Catania, Italy
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228
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Schoknecht K, David Y, Heinemann U. The blood-brain barrier-gatekeeper to neuronal homeostasis: clinical implications in the setting of stroke. Semin Cell Dev Biol 2014; 38:35-42. [PMID: 25444848 DOI: 10.1016/j.semcdb.2014.10.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 10/24/2014] [Accepted: 10/31/2014] [Indexed: 12/23/2022]
Abstract
The blood-brain barrier is part of the neurovascular unit and serves as a functional and anatomical barrier between the blood and the extracellular space. It controls the flow of solutes in and out of the brain thereby providing an optimal environment for neuronal functioning. Paracellular transport between endothelial cells is restricted by tight junctions and transendothelial transport is reduced and more selective compared to capillaries of other organs. Further, the blood-brain barrier is involved in controlling blood flow and it is the site for signaling damage of the nervous system to the peripheral immune system. As an important player in brain homeostasis, blood-brain barrier dysfunction has been implicated in the pathophysiology of many brain diseases including stroke, traumatic brain injury, brain tumors, epilepsy and neurodegenerative disorders. In this article - highlighting recent advances in basic science - we review the features of the blood-brain barrier and their significance for neuronal homeostasis to discuss clinical implications for neurological complications following cerebral ischemia.
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Affiliation(s)
- Karl Schoknecht
- Institute for Neurophysiology, Charité - University Medicine Berlin, Germany
| | - Yaron David
- Departments of Physiology & Cell Biology, Cognitive & Brain Sciences, The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Uwe Heinemann
- Institute for Neurophysiology, Charité - University Medicine Berlin, Germany.
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229
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Sitges M, Gómez CD, Aldana BI. Sertraline reduces IL-1β and TNF-α mRNA expression and overcomes their rise induced by seizures in the rat hippocampus. PLoS One 2014; 9:e111665. [PMID: 25364907 PMCID: PMC4218797 DOI: 10.1371/journal.pone.0111665] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 09/30/2014] [Indexed: 12/26/2022] Open
Abstract
We recently discovered that the antidepressant sertraline is an effective inhibitor of hippocampus presynaptic Na+ channel permeability invitro and of tonic-clonic seizures in animals invivo. Several studies indicate that the pro-inflammatory cytokines in the central nervous system are increased in epilepsy and depression. On the other hand inhibition of Na+ channels has been shown to decrease pro-inflammatory cytokines in microglia. Therefore, the possibility that sertraline could overcome the rise in pro-inflammatory cytokine expression induced by seizures has been investigated. For this purpose, IL-1β and TNF-α mRNA expression was determined by RT-PCR in the hippocampus of rats administered once, or for seven consecutive days with sertraline at a low dose (0.75 mg/kg). The effect of sertraline at doses within the range of 0.75 to 25 mg/kg on the increase in IL-1β and TNF-α mRNA expression accompanying generalized tonic-clonic seizures, and increase in the pro-inflammatory cytokines expression induced by lipopolysaccharide was also investigated. We found that under basal conditions, a single 0.75 mg/kg sertraline dose decreased IL-1β mRNA expression, and also TNF-α expression after repeated doses. The increase in IL-1β and TNF-α expression induced by the convulsive agents and by the inoculation of lipopolysaccharide in the hippocampus was markedly reduced by sertraline also. Present results indicate that a reduction of brain inflammatory processes may contribute to the anti-seizure sertraline action, and that sertraline can be safely and successfully used at low doses to treat depression in epileptic patients.
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Affiliation(s)
- María Sitges
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Distrito Federal, México
- * E-mail:
| | - Carlos D. Gómez
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Distrito Federal, México
| | - Blanca I. Aldana
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Distrito Federal, México
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230
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Gullo F, Amadeo A, Donvito G, Lecchi M, Costa B, Constanti A, Wanke E. Atypical "seizure-like" activity in cortical reverberating networks in vitro can be caused by LPS-induced inflammation: a multi-electrode array study from a hundred neurons. Front Cell Neurosci 2014; 8:361. [PMID: 25404893 PMCID: PMC4217498 DOI: 10.3389/fncel.2014.00361] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 10/13/2014] [Indexed: 12/21/2022] Open
Abstract
We show here that a mild sterile inflammation induced by the endotoxin lipopolysaccharide (LPS), in a neuron/astrocyte/microglial cortical network, modulates neuronal excitability and can initiate long-duration burst events resembling epileptiform seizures, a recognized feature of various central nervous neurodegenerative, neurological and acute systemic diseases associated with neuroinflammation. To study this action, we simultaneously analyzed the reverberating bursting activity of a hundred neurons by using in vitro multi-electrode array methods. ∼5 h after LPS application, we observed a net increase in the average number of spikes elicited in engaged cells and within each burst, but no changes neither in spike waveforms nor in burst rate. This effect was characterized by a slow, twofold exponential increase of the burst duration and the appearance of rarely occurring long burst events that were never seen during control recordings. These changes and the time-course of microglia-released proinflammatory cytokine, tumor necrosis factor-alpha (TNF-α), were blocked by pre-treatment with 50 nM minocycline, an established anti-inflammatory agent which was inactive when applied alone. Assay experiments also revealed that application of 60 pM exogenous TNF-α after 12–15 h, produced non-washable changes of neuronal excitability, completely different from those induced by LPS, suggesting that TNF-α release alone was not responsible for our observed findings. Our results indicate that the link between neuroinflammation and hyperexcitability can be unveiled by studying the long-term activity of in vitro neuronal/astrocyte/microglial networks.
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Affiliation(s)
- Francesca Gullo
- Department of Biotechnologies and Biosciences, University of Milano-Bicocca, Milan Italy
| | - Alida Amadeo
- Department of Biomolecular Sciences and Biotechnology, University of Milan, Milan Italy
| | - Giulia Donvito
- Department of Biotechnologies and Biosciences, University of Milano-Bicocca, Milan Italy
| | - Marzia Lecchi
- Department of Biotechnologies and Biosciences, University of Milano-Bicocca, Milan Italy
| | - Barbara Costa
- Department of Biotechnologies and Biosciences, University of Milano-Bicocca, Milan Italy
| | | | - Enzo Wanke
- Department of Biotechnologies and Biosciences, University of Milano-Bicocca, Milan Italy
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231
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Merbl Y, Sommer A, Chai O, Aroch I, Zimmerman G, Friedman A, Soreq H, Shamir M. Tumor necrosis factor-α and interleukin-6 concentrations in cerebrospinal fluid of dogs after seizures. J Vet Intern Med 2014; 28:1775-81. [PMID: 25308784 PMCID: PMC4895630 DOI: 10.1111/jvim.12462] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Revised: 06/06/2014] [Accepted: 08/21/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Idiopathic and acquired epilepsy are common in dogs. Up to 30% of these dogs are refractory to pharmacological treatment. Accumulating experimental evidence indicates that brain immune response and presence of inflammatory mediators decrease the threshold for individual seizures and contribute to epileptogenesis. HYPOTHESIS Dogs with seizures have higher cerebrospinal interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentrations compared to dogs with no seizures. METHODS A prospective double blinded study; cerebrospinal fluid (CSF) and serum IL-6, TNF-α and total protein (TP) concentrations were measured by a blinded investigator for the study group and CSF IL-6 and TNF-α levels and TP concentrations were measured in the control group (CG). ANIMALS Dogs presented with seizures that had enough CSF collected to allow analysis were included in the study group. Twelve apparently healthy, quarantined, stray dogs served as control (CG). RESULTS Cerebrospinal fluid TNF-α and IL-6 concentrations were significantly higher (P = .011, P = .039) in dogs with seizures (0 ± 70.66, 0.65 ± 10.93 pg/mL) compared to the CG (0 ± 19, 0.73 ± 0.55 pg/mL). When assessing cytokine concentrations of specifically the idiopathic epilepsy (IE) dogs compared to the CG, only TNF-α concentrations (8.66 ± 62, 0 ± 19 pg/mL) were significantly higher (P = .01). CSF TP concentrations were not significantly higher in the study dogs compared to the CG. CONCLUSIONS AND CLINICAL IMPORTANCE Higher TNF-α and IL-6 concentration in the CSF of dogs with naturally occurring seizures. The higher supports the hypothesis that inflammatory processes through certain mediators play a role in the pathogenesis of seizures in dogs.
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Affiliation(s)
- Y. Merbl
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
| | - A. Sommer
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
| | - O. Chai
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
| | - I. Aroch
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
| | - G. Zimmerman
- Edmond and Lily Safra Center of Brain ScienceHebrew University of JerusalemJerusalemIsrael
| | - A. Friedman
- Department of Life SciencesBen‐Gurion University of the NegevBeer ShevaIsrael
| | - H. Soreq
- Edmond and Lily Safra Center of Brain ScienceHebrew University of JerusalemJerusalemIsrael
- Department of Biological ChemistryAlexander Silberman Institute of Life SciencesHebrew University of JerusalemJerusalemIsrael
| | - M.H. Shamir
- Koret School of Veterinary MedicineHebrew University of JerusalemRehovotIsrael
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232
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Bañuelos-Cabrera I, Valle-Dorado MG, Aldana BI, Orozco-Suárez SA, Rocha L. Role of Histaminergic System in Blood–Brain Barrier Dysfunction Associated with Neurological Disorders. Arch Med Res 2014; 45:677-86. [DOI: 10.1016/j.arcmed.2014.11.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 11/14/2014] [Indexed: 12/23/2022]
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233
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Li Q, Dong C, Li W, Bu W, Wu J, Zhao W. Neuropeptide Y protects cerebral cortical neurons by regulating microglial immune function. Neural Regen Res 2014; 9:959-67. [PMID: 25206918 PMCID: PMC4146213 DOI: 10.4103/1673-5374.133140] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2014] [Indexed: 11/29/2022] Open
Abstract
Neuropeptide Y has been shown to inhibit the immunological activity of reactive microglia in the rat cerebral cortex, to reduce N-methyl-D-aspartate current (INMDA) in cortical neurons, and protect neurons. In this study, after primary cultured microglia from the cerebral cortex of rats were treated with lipopolysaccharide, interleukin-1β and tumor necrosis factor-α levels in the cell culture medium increased, and mRNA expression of these cytokines also increased. After primary cultured cortical neurons were incubated with the lipopolysaccharide-treated microglial conditioned medium, peak INMDA in neurons increased. These effects of lipopolysaccharide were suppressed by neuropeptide Y. After addition of the neuropeptide Y Y1 receptor antagonist BIBP3226, the effects of neuropeptide Y completely disappeared. These results suggest that neuropeptide Y prevents excessive production of interleukin-1β and tumor necrosis factor-α by inhibiting microglial reactivity. This reduces INMDA in rat cortical neurons, preventing excitotoxicity, thereby protecting neurons.
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Affiliation(s)
- Qijun Li
- Graduate School, Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Changzheng Dong
- Department of Functional Neurosurgery, Hebei General Hospital, Shijiazhuang, Hebei Province, China
| | - Wenling Li
- Department of Functional Neurosurgery, Hebei General Hospital, Shijiazhuang, Hebei Province, China
| | - Wei Bu
- Department of Neurosurgery, Third Hospital, Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Jiang Wu
- Department of Functional Neurosurgery, Hebei General Hospital, Shijiazhuang, Hebei Province, China
| | - Wenqing Zhao
- Graduate School, Hebei Medical University, Shijiazhuang, Hebei Province, China ; Department of Functional Neurosurgery, Hebei General Hospital, Shijiazhuang, Hebei Province, China
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234
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Theophylline potentiates lipopolysaccharide-induced NO production in cultured astrocytes. Neurochem Res 2014; 39:107-16. [PMID: 24234846 DOI: 10.1007/s11064-013-1195-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 10/15/2013] [Accepted: 11/06/2013] [Indexed: 12/13/2022]
Abstract
Elucidation of the functions of astrocytes is important for understanding of the pathogenic mechanism of various neurodegenerative diseases. Theophylline is a common drug for bronchial asthma and occasionally develops side-effects, such as acute encephalopathy; although the pathogenic mechanism of the side-effects is unknown. The lipopolysaccharide (LPS)-induced nitricoxide (NO) production is generally used for an index of the activation of astrocyte in vitro. In this study, in order to elucidate the effect of theophylline on the astrocytic functions, we examined the LPS-induced NO production and the expression of iNOS in cultured rat cortex astrocytes.Theophylline alone could not induce the NO production; however, NO production induced by LPS was enhanced by theophylline in a dose-dependent manner; and by isobutylmethylxanthine, a phosphodiesterase inhibitor. The theophylline enhancement of LPS-induced NO production was further increased by dibutyryl cyclic AMP, a membrane-permeable cAMP analog; and by forskolin, an adenylate cyclase activator. When the cells were preincubated with Rp-8-Br-cAMP, an inhibitor of protein kinase A, the theophylline enhancement of LPS-induced NO production was decreased. The extent of iNOS protein expression induced by LPS was also enhanced by theophylline.It is likely that phosphodiesterase inhibition is a major action mechanism for the theophylline enhancement of LPS-induced NO production in astrocytes. Theophylline-induced acute encephalopathy might be due to the hyper-activation of astrocytes via cAMP signaling to produce excess amount of NO.
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235
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Legido A, Katsetos CD. Experimental studies in epilepsy: immunologic and inflammatory mechanisms. Semin Pediatr Neurol 2014; 21:197-206. [PMID: 25510941 DOI: 10.1016/j.spen.2014.10.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In this article, we review the literature based on experimental studies lending credence to a relationship between epilepsy and immune-mediated mechanisms linked to central nervous system innate immunity. The brain innate immunity responses to neuronal injury or excessive neuronal activity are mediated by resident microglia and astroglia, but also neurons play an immunomodulatory role. Antigens or antibodies applied to the brain trigger an epileptogenic and inflammatory response. Furthermore, seizure activity and status epilepticus elicit the production and release of proinflammatory cytokines and chemokines. The immune pathogenesis of epilepsy involves complex cell-to-cell interactions including a cross talk between astrocytes and neurons, between astrocytes and brain microvascular endothelial cells, as well as reciprocal leukocyte-endothelial interactions in the context of disruption of the blood-brain barrier. There is a large body of literature from experimental studies showing that seizures can initiate a cascade of innate and adaptive immune responses from various cellular sources and perpetuate neuroinflammation through mechanisms involving transcription of inflammatory genes or posttranslational changes in cytokine release machinery. These inflammatory processes could also possibly contribute to the pathogenesis of comorbidities often associated with epilepsy. This opens exciting possibilities for the development of disease-modifying drugs aimed at mitigating neuroinflammation as a means of ameliorating epileptogenesis and lessening or preventing postictal brain injury.
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Affiliation(s)
- Agustín Legido
- Section of Neurology, St. Christopher's Hospital for Children, Department of Pediatrics, Drexel University College of Medicine, Philadelphia, PA.
| | - Christos D Katsetos
- Section of Neurology, St. Christopher's Hospital for Children, Department of Pediatrics, Drexel University College of Medicine, Philadelphia, PA
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236
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Fukuda M, Hino H, Suzuki Y, Takahashi H, Morimoto T, Ishii E. Postnatal interleukin-1β enhances adulthood seizure susceptibility and neuronal cell death after prolonged experimental febrile seizures in infantile rats. Acta Neurol Belg 2014; 114:179-85. [PMID: 24002650 DOI: 10.1007/s13760-013-0246-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 08/14/2013] [Indexed: 12/30/2022]
Abstract
Febrile seizures (FS) are recognized as an antecedent to the development of temporal lobe epilepsy with hippocampal sclerosis (TLE-HS), but it is unclear whether prolonged FS are a direct cause of TLE-HS. Here, we used a rat model of infantile FS to study the effects of inflammatory cytokines on seizure susceptibility and neuronal death in adults. Prolonged hyperthermia-induced seizures (pHS) were induced in male Lewis rats at post natal day (P) 10. Cytokines were administered twice intranasally, once immediately after pHS and once the following day. The effects of intranasal interleukin (IL)-1β or tumor necrosis factor (TNF) α were tested in rats undergoing a single episode of pHS (P10) and in rats undergoing repeated pHS (P10 and P12). Seizure susceptibility was tested at P70-73 by quantifying the seizure onset time (SOT) after kainic acid administration, and neuronal cell injury and gliosis in adulthood. SOT significantly reduced in rats receiving IL-1β together with repeated pHS, whereas no significant effects were seen in rats receiving IL-1β after a single pHS episode, or in rats receiving TNFα. Hippocampal neuronal cell loss was observed in the CA3 region of rats receiving IL-1β together with repeated pHS; however, there was no significant change in gliosis among each group. Our results are consistent with the hypothesis that excessive production of IL-1β after repeated prolonged FS can enhance adult seizure susceptibility and neuronal cell death, and might contribute to the development of TLE-HS.
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Affiliation(s)
- Mitsumasa Fukuda
- Department of Pediatrics, Ehime University Graduate School of Medicine, 454 Shitsukawa, Toon, Ehime, 791-0295, Japan,
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237
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Kanner AM. Is depression associated with an increased risk of treatment-resistant epilepsy? Research strategies to investigate this question. Epilepsy Behav 2014; 38:3-7. [PMID: 25260238 DOI: 10.1016/j.yebeh.2014.06.027] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 06/24/2014] [Indexed: 11/18/2022]
Abstract
Persons with epilepsy (PWE) have a higher risk of developing depressive disorders (DDs), and people with primary DD have an increased risk of developing epilepsy. Furthermore, a lifetime history of DD has been associated with a worse response of the seizure disorder to pharmacotherapy and epilepsy surgery. The first part of this article reviews the literature of this problem with the intention of highlighting the neurobiologic pathogenic mechanisms operant in DD with a potential to facilitate the epileptogenic process and/or cortical hyperexcitability in humans and experimental animal studies of depression. They include the following: (i) a hyperactive hypothalamic-pituitary-adrenal axis and the associated structural and functional abnormalities of limbic structures, (ii) increased glutamatergic activity and decreased GABAergic and serotonergic activity, and (iii) immunologic disturbances. In the second part of this article, we suggest research strategies to test the hypothesis of whether depression worsens the course of epilepsy and identify the pathogenic mechanisms operant in this process.
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Affiliation(s)
- Andres M Kanner
- Department of Neurology, University of Miami, Miller School of Medicine, USA.
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238
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Aureli A, Sebastiani P, Del Beato T, Marimpietri AE, Graziani A, Sechi E, Di Loreto S. Involvement of IL-6 and IL-1 receptor antagonist on intellectual disability. Immunol Lett 2014; 162:124-31. [PMID: 25124963 DOI: 10.1016/j.imlet.2014.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 07/31/2014] [Accepted: 08/03/2014] [Indexed: 01/17/2023]
Abstract
Imbalances in the regulation of pro-inflammatory cytokines have been increasingly correlated with several neurodevelopmental disorders and their role in neuronal development is being investigated. To assess the possible influence of cytokines on the onset of intellectual disability (ID), we studied the polymorphisms of thirteen proinflammatory cytokine genes in 81 patients and 61 healthy controls. We demonstrated a significant association of interleukin-6 (IL-6) single-nucleotide polymorphism (SNP) (-174 G/C and nt565 G/A), and interleukin-1 receptor antagonist (IL-1RA) (Mspa-I 11100) SNP with ID. Moreover, the IL-6 SNPs is an unfavorable genetic predisposition for females. The evaluation of circulating levels of IL-6 and IL-1RA showed that the serum concentrations of IL-6 were significantly higher in ID patients than in controls. These data suggest that functional cytokine gene polymorphisms may influence the development of ID.
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Affiliation(s)
- A Aureli
- Institute of Translational Pharmacology (IFT) - National Council of Research (CNR), L'Aquila, Italy
| | - P Sebastiani
- Institute of Translational Pharmacology (IFT) - National Council of Research (CNR), L'Aquila, Italy
| | - T Del Beato
- Institute of Translational Pharmacology (IFT) - National Council of Research (CNR), L'Aquila, Italy
| | - A E Marimpietri
- Childhood and Adolescence Neuropsychiatric Clinic, University of L'Aquila, ASL n. 4, L'Aquila, Italy
| | - A Graziani
- Childhood and Adolescence Neuropsychiatric Clinic, University of L'Aquila, ASL n. 4, L'Aquila, Italy
| | - E Sechi
- Childhood and Adolescence Neuropsychiatric Clinic, University of L'Aquila, ASL n. 4, L'Aquila, Italy
| | - S Di Loreto
- Institute of Translational Pharmacology (IFT) - National Council of Research (CNR), L'Aquila, Italy.
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León-Rivera I, Villeda-Hernández J, Campos-Peña V, Aguirre-Moreno A, Estrada-Soto S, Navarrete-Vázquez G, Rios MY, Aguilar-Guadarrama B, Castillo-España P, Rivera-Leyva JC. Evaluation of the neuroprotective activity of stansin 6, a resin glycoside from Ipomoea stans. Bioorg Med Chem Lett 2014; 24:3541-5. [DOI: 10.1016/j.bmcl.2014.05.055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 05/14/2014] [Accepted: 05/15/2014] [Indexed: 11/30/2022]
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240
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Steinborn B, Zarowski M, Winczewska-Wiktor A, Wójcicka M, Młodzikowska-Albrecht J, Losy J. Concentration of Il-1β, Il-2, Il-6, TNFα in the blood serum in children with generalized epilepsy treated by valproate. Pharmacol Rep 2014; 66:972-5. [PMID: 25443723 DOI: 10.1016/j.pharep.2014.06.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 06/05/2014] [Accepted: 06/05/2014] [Indexed: 01/31/2023]
Abstract
BACKGROUND The aim of the study was the comparison of concentrations of IL-1β, IL-2, IL-6 and TNFα before and after valproate (VPA) treatment in blood serum in patients with generalized seizures diagnosed and treated in the Department of Developmental Neurology, Poznan University of Medical Sciences from January 2006 to May 2007. METHODS The analysis was conducted in a group of 21 patients with well controlled, generalized seizures (mean age 7.7±4.7 years) before and after 4-6 months of VPA therapy. Quantitative determination IL-1β, IL-2, IL-6 and TNFα were performed with method of enzyme-linked immunosorbent assay (ELISA). The serum drug concentration was determined with the use of fluorescence-polarization-immunoassay system (FPIA). RESULTS The concentration of IL-6 in blood serum of patients decreased significantly (p<0.001) after 4-6 months of VPA therapy, but concentration of IL-1β (p=0.732), IL-2 (p=0.865), TNFα (p=0.079) did not change significantly. The serum concentration of VPA in all of patients was in therapeutic range (mean 77.53±19.71μg/ml). CONCLUSIONS The serum level of pro-inflammatory IL-6 in patients with generalized epilepsy decreased in statistically significant way during VPA therapy, so the anti-inflammatory properties of VPA are also important for the effective control of seizure. Due to the incompatibility of reports on the influence of VPA on cytokine system in patients with generalized epilepsy, this problem needs more investigations, especially in the group of children.
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Affiliation(s)
- Barbara Steinborn
- Department of Developmental Neurology, Poznan University of Medical Sciences, Poznań, Poland
| | - Marcin Zarowski
- Department of Developmental Neurology, Poznan University of Medical Sciences, Poznań, Poland.
| | - Anna Winczewska-Wiktor
- Department of Developmental Neurology, Poznan University of Medical Sciences, Poznań, Poland
| | - Marlena Wójcicka
- Department of Clinical Neuroimmunology, Chair of Neurology, Poznan University of Medical Sciences, Poznań, Poland
| | | | - Jacek Losy
- Department of Clinical Neuroimmunology, Chair of Neurology, Poznan University of Medical Sciences, Poznań, Poland; Neuroimmunological Unit, Institute of Experimental and Clinical Medicine, Polish Academy of Sciences, Poznań, Poland
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241
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Yeghiazaryan M, Rutkowska-Wlodarczyk I, Konopka A, Wilczyński GM, Melikyan A, Korkotian E, Kaczmarek L, Figiel I. DP-b99 modulates matrix metalloproteinase activity and neuronal plasticity. PLoS One 2014; 9:e99789. [PMID: 24918931 PMCID: PMC4053404 DOI: 10.1371/journal.pone.0099789] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 05/19/2014] [Indexed: 12/13/2022] Open
Abstract
DP-b99 is a membrane-activated chelator of zinc and calcium ions, recently proposed as a therapeutic agent. Matrix metalloproteinases (MMPs) are zinc-dependent extracellularly operating proteases that might contribute to synaptic plasticity, learning and memory under physiological conditions. In excessive amounts these enzymes contribute to a number of neuronal pathologies ranging from the stroke to neurodegeneration and epileptogenesis. In the present study, we report that DP-b99 delays onset and severity of PTZ-induced seizures in mice, as well as displays neuroprotective effect on kainate excitotoxicity in hippocampal organotypic slices and furthermore blocks morphological reorganization of the dendritic spines evoked by a major neuronal MMP, MMP-9. Taken together, our findings suggest that DP-b99 may inhibit neuronal plasticity driven by MMPs, in particular MMP-9, and thus may be considered as a therapeutic agent under conditions of aberrant plasticity, such as those subserving epileptogenesis.
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Affiliation(s)
- Marine Yeghiazaryan
- Department of Neurophysiology, The Nencki Institute of Experimental Biology, Warsaw, Poland
| | | | - Anna Konopka
- Department of Neurophysiology, The Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Grzegorz M. Wilczyński
- Department of Neurophysiology, The Nencki Institute of Experimental Biology, Warsaw, Poland
| | | | | | - Leszek Kaczmarek
- Department of Molecular and Cellular Neurobiology, The Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Izabela Figiel
- Department of Molecular and Cellular Neurobiology, The Nencki Institute of Experimental Biology, Warsaw, Poland
- * E-mail:
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242
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Chiavegato A, Zurolo E, Losi G, Aronica E, Carmignoto G. The inflammatory molecules IL-1β and HMGB1 can rapidly enhance focal seizure generation in a brain slice model of temporal lobe epilepsy. Front Cell Neurosci 2014; 8:155. [PMID: 24936172 PMCID: PMC4047964 DOI: 10.3389/fncel.2014.00155] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 05/16/2014] [Indexed: 12/12/2022] Open
Abstract
Epilepsy is a neurological disorder characterized by a hyperexcitable brain tissue and unpredictable seizures, i.e., aberrant firing discharges in large neuronal populations. It is well established that proinflammatory cytokines, in addition to their canonical involvement in the immune response, have a crucial role in the mechanism of seizure generation. The purpose of the present study was to investigate the role of interleukin-1β (IL-1β) and high mobility group B1 (HMGB1) in the generation of seizure-like discharges using two models of focal epilepsy in a rat entorhinal cortex slice preparation. Seizure like-discharges were evoked by either slice perfusion with low Mg2+ and picrotoxin or with a double NMDA local stimulation in the presence of the proconvulsant 4-amino-pyridine. The effects of IL-1β or HMGB1 were evaluated by monitoring seizure discharge generation through laser scanning microscope imaging of Ca2+ signals from neurons and astrocytes. In the picrotoxin model, we revealed that both cytokines increased the mean frequency of spontaneous ictal-like discharges, whereas only IL-1β reduced the latency and prolonged the duration of the first ictal-like event. In the second model, a single NMDA pulse, per se ineffective, became successful when it was performed after IL-β or HMGB1 local applications. These findings demonstrate that both IL-1β and HMGB1 can rapidly lower focal ictal event threshold and strengthen the possibility that targeting these inflammatory pathways may represent an effective therapeutic strategy to prevent seizures.
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Affiliation(s)
- Angela Chiavegato
- Department of Biomedical Sciences and CNR Institute of Neuroscience, University of Padova Padova, Italy
| | - Emanuele Zurolo
- Department of (Neuro)Pathology, Academic Medical Center, and Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, Netherlands ; SEIN - Stichting Epilepsie Instellingen Nederland Heemstede, Netherlands
| | - Gabriele Losi
- Department of Biomedical Sciences and CNR Institute of Neuroscience, University of Padova Padova, Italy
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, and Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, Netherlands ; SEIN - Stichting Epilepsie Instellingen Nederland Heemstede, Netherlands
| | - Giorgio Carmignoto
- Department of Biomedical Sciences and CNR Institute of Neuroscience, University of Padova Padova, Italy
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243
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Bogdanović RM, Syvänen S, Michler C, Russmann V, Eriksson J, Windhorst AD, Lammertsma AA, de Lange EC, Voskuyl RA, Potschka H. (R)-[11C]PK11195 brain uptake as a biomarker of inflammation and antiepileptic drug resistance: evaluation in a rat epilepsy model. Neuropharmacology 2014; 85:104-12. [PMID: 24880085 DOI: 10.1016/j.neuropharm.2014.05.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 04/22/2014] [Accepted: 05/09/2014] [Indexed: 01/02/2023]
Abstract
Neuroinflammation has been suggested as a key determinant of the intrinsic severity of epilepsy. Glial cell activation and associated inflammatory signaling can influence seizure thresholds as well as the pharmacodynamics and pharmacokinetics of antiepileptic drugs. Based on these data, we hypothesized that molecular imaging of microglia activation might serve as a tool to predict drug refractoriness of epilepsy. Brain uptake of (R)-[11C]PK11195, a ligand of the translocator protein 18 kDa and molecular marker of microglia activation, was studied in a chronic model of temporal lobe epilepsy in rats with selection of phenobarbital responders and non-responders. In rats with drug-sensitive epilepsy, (R)-[11C]PK11195 brain uptake values were comparable to those in non-epileptic controls. Analysis in non-responders revealed enhanced brain uptake of up to 39% in different brain regions. The difference might be related to the fact that non-responders exhibited higher baseline seizure frequencies than responders indicating a more pronounced intrinsic disease severity. In hippocampal sections, ED1 immunostaining argued against a general difference in microglia activation between both groups. Our data suggest that TSPO PET imaging might serve as a biomarker for drug resistance in temporal lobe epilepsy. However, it needs to be considered that our findings indicate that the TSPO PET data might merely reflect seizure frequency. Future experimental and clinical studies should further evaluate the validity of TSPO PET data to predict the response to phenobarbital and other antiepileptic drugs in longitudinal studies with scanning before drug exposure and with a focus on the early phase following an epileptogenic brain insult.
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Affiliation(s)
- Renée Marie Bogdanović
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University, Munich, Germany; Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University, Munich, Germany
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Christina Michler
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Vera Russmann
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Jonas Eriksson
- Department Medicinal Chemistry, Preclinical PET Platform, Uppsala University, Sweden
| | - Albert D Windhorst
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Adriaan A Lammertsma
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | | | - Rob A Voskuyl
- Division of Pharmacology, LACDR, Leiden University, Leiden, The Netherlands; SEIN - Epilepsy Institutes of The Netherlands Foundation, Heemstede, The Netherlands
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University, Munich, Germany.
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244
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Richter F, Lütz W, Eitner A, Leuchtweis J, Lehmenkühler A, Schaible HG. Tumor necrosis factor reduces the amplitude of rat cortical spreading depression in vivo. Ann Neurol 2014; 76:43-53. [PMID: 24798682 DOI: 10.1002/ana.24176] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 05/02/2014] [Accepted: 05/02/2014] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Brain damage and ischemia often trigger cortical spreading depression (CSD), which aggravates brain damage. The proinflammatory cytokine tumor necrosis factor (TNF) is significantly upregulated during brain damage, but it is unknown whether TNF influences spreading depression in cerebral cortex in vivo. This question is important because TNF not only furthers inflammatory reactions but might also be neuroprotective. Here we tested the hypothesis that TNF affects CSD, and we explored the direction in which CSD is modified by TNF. METHODS CSD, elicited by pressure microinjection of KCl, was recorded in anesthetized rats and mice. TNF was administered locally into a trough, providing local TNF treatment of a cortical area. For further analysis, antibodies to TNF receptor (TNFR) 1 or 2 were applied, or CSD was monitored in TNFR1 and TNFR2 knockout mice. γ-Aminobutyric acid (GABA)A receptors were blocked by bicuculline. Immunohistochemistry localized the cortical expression of TNFR1 and TNFR2. RESULTS Local application of TNF to the cortex reduced dose-dependently the amplitude of CSD. This effect was prevented by blockade or knockout of TNFR2 but not by blockade or knockout of TNFR1. TNFR2 was localized at cortical neurons including parvalbumin-positive inhibitory interneurons, and blockade of GABAA receptors by bicuculline prevented the reduction of CSD amplitudes by TNF. INTERPRETATION We identified a functional link between TNF and CSD. TNF activates TNFR2 in cortical inhibitory interneurons. The resulting release of GABA reduces CSD amplitudes. In this manner, TNF might be neuroprotective in pathological conditions.
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Affiliation(s)
- Frank Richter
- Institute of Physiology I/Neurophysiology, Jena University Hospital-Friedrich Schiller University Jena, Jena
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245
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Ho TY, Tang NY, Hsiang CY, Hsieh CL. Uncaria rhynchophylla and rhynchophylline improved kainic acid-induced epileptic seizures via IL-1β and brain-derived neurotrophic factor. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2014; 21:893-900. [PMID: 24636743 DOI: 10.1016/j.phymed.2014.01.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 11/08/2013] [Accepted: 01/31/2014] [Indexed: 06/03/2023]
Abstract
Uncaria rhynchophylla (UR) has been used for the treatment of convulsions and epilepsy in traditional Chinese medicine. This study reported the major anti-convulsive signaling pathways and effective targets of UR and rhynchophylline (RP) using genomic and immunohistochemical studies. Epileptic seizure model was established by intraperitoneal injection of kainic acid (KA) in rats. Electroencephalogram and electromyogram recordings indicated that UR and RP improved KA-induced epileptic seizures. Toll-like receptor (TLR) and neurotrophin signaling pathways were regulated by UR in both cortex and hippocampus of KA-treated rats. KA upregulated the expression levels of interleukin-1β (IL-1β) and brain-derived neurotrophin factor (BDNF), which were involved in TLR and neurotrophin signaling pathways, respectively. However, UR and RP downregulated the KA-induced IL-1β and BDNF gene expressions. Our findings suggested that UR and RP exhibited anti-convulsive effects in KA-induced rats via the regulation of TLR and neurotrophin signaling pathways, and the subsequent inhibition of IL-1β and BDNF gene expressions.
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Affiliation(s)
- Tin-Yun Ho
- Graduate Institute of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan
| | - Nou-Ying Tang
- School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan
| | - Chien-Yun Hsiang
- Department of Microbiology, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Ching-Liang Hsieh
- Graduate Institute of Integrated Medicine, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan; Acupuncture Research Center, China Medical University, Taichung 40402, Taiwan; Department of Chinese Medicine, China Medical University Hospital, Taichung 40402, Taiwan.
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246
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Kovács Z, Dobolyi Á, Juhász G, Kékesi KA. Lipopolysaccharide induced increase in seizure activity in two animal models of absence epilepsy WAG/Rij and GAERS rats and Long Evans rats. Brain Res Bull 2014; 104:7-18. [DOI: 10.1016/j.brainresbull.2014.03.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Revised: 03/20/2014] [Accepted: 03/24/2014] [Indexed: 02/04/2023]
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Pardo CA, Nabbout R, Galanopoulou AS. Mechanisms of epileptogenesis in pediatric epileptic syndromes: Rasmussen encephalitis, infantile spasms, and febrile infection-related epilepsy syndrome (FIRES). Neurotherapeutics 2014; 11:297-310. [PMID: 24639375 PMCID: PMC3996116 DOI: 10.1007/s13311-014-0265-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The mechanisms of epileptogenesis in pediatric epileptic syndromes are diverse, and may involve disturbances of neurodevelopmental trajectories, synaptic homeostasis, and cortical connectivity, which may occur during brain development, early infancy, or childhood. Although genetic or structural/metabolic factors are frequently associated with age-specific epileptic syndromes, such as infantile spasms and West syndrome, other syndromes may be determined by the effect of immunopathogenic mechanisms or energy-dependent processes in response to environmental challenges, such as infections or fever in normally-developed children during early or late childhood. Immune-mediated mechanisms have been suggested in selected pediatric epileptic syndromes in which acute and rapidly progressive encephalopathies preceded by fever and/or infections, such as febrile infection-related epilepsy syndrome, or in chronic progressive encephalopathies, such as Rasmussen encephalitis. A definite involvement of adaptive and innate immune mechanisms driven by cytotoxic CD8(+) T lymphocytes and neuroglial responses has been demonstrated in Rasmussen encephalitis, although the triggering factor of these responses remains unknown. Although the beneficial response to steroids and adrenocorticotropic hormone of infantile spasms, or preceding fever or infection in FIRES, may support a potential role of neuroinflammation as pathogenic factor, no definite demonstration of such involvement has been achieved, and genetic or metabolic factors are suspected. A major challenge for the future is discovering pathogenic mechanisms and etiological factors that facilitate the introduction of novel targets for drug intervention aimed at interfering with the disease mechanisms, therefore providing putative disease-modifying treatments in these pediatric epileptic syndromes.
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Affiliation(s)
- Carlos A Pardo
- Department of Neurology, Division of Neuroimmunology and Neuroinfectious Disorders, Center for Pediatric Rasmussen Syndrome, Johns Hopkins University School of Medicine, Baltimore, MD, USA,
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Heuser K, Szokol K, Taubøll E. The role of glial cells in epilepsy. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 2014; 134:37-41. [PMID: 24429754 DOI: 10.4045/tidsskr.12.1344] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
BACKGROUND Brain research in the last century was mainly directed at neurons, with the role of glia assumed to be limited to repair, supplying nutrients and above all acting as a packing material between neurons. In recent years, the importance of glial cells for normal brain function has been recognised. This article summarizes knowledge of glial cells of relevance to epilepsy. METHOD The article is based on a literature search in PubMed as well as the authors' clinical and research experience. RESULTS Astrocytes are the largest subgroup of glial cells and, in common with neurons, have diverse membrane transporters, ion channels and receptors. Among the most important roles of astrocytes are the uptake and redistribution of ions and water, glucose metabolism and communication with nerve cells. Disturbances in all of these functions have been associated with epilepsy. INTERPRETATION Epilepsy has previously been regarded as exclusively a disturbance in the functioning of neurons and especially of their contact points, the synapses. The mechanisms of action of today's anti-epileptic drugs are therefore primarily directed at neuronal channels and receptors. New knowledge of the role played by glial cells could increase our understanding of how epilepsy arises and could lead to new treatment strategies.
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249
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Vitaliti G, Pavone P, Mahmood F, Nunnari G, Falsaperla R. Targeting inflammation as a therapeutic strategy for drug-resistant epilepsies: an update of new immune-modulating approaches. Hum Vaccin Immunother 2014; 10:868-75. [PMID: 24609096 DOI: 10.4161/hv.28400] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
An increasing body of literature data suggests that inflammation, and in particular neuroinflammation, is involved in the pathophysiology of particular forms of epilepsy and convulsive disorders. Animal models have been used to identify inflammatory triggers in epileptogenesis and inflammation has recently been shown to enhance seizures. For example, pharmacological blockade of the IL-1beta/IL-1 receptor type 1 axis during epileptogenesis has been demonstrated to provide neuroprotection in temporal lobe epilepsy. Furthermore, experimental models have suggested that neural damage and the onset of spontaneous recurrent seizures are modulated via complex interactions between innate and adaptive immunity. However, it has also been suggested that inflammation can occur as a result of epilepsy, since animal models have also shown that seizure activity can induce neuroinflammation, and that recurrent seizures maintain chronic inflammation, thereby perpetuating seizures. On the basis of these observations, it has been suggested that immune-mediated therapeutic strategies may be beneficial for treating some drug resistant epilepsies with an underlying demonstrable inflammatory process. Although the potential mechanisms of immunotherapeutic strategies in drug-resistant seizures have been extensively discussed, evidence on the efficacy of such therapy is limited. However, recent research efforts have been directed toward utilizing the potential therapeutic benefits of anti-inflammatory agents in neurological disease and these are now considered prime candidates in the ongoing search for novel anti-epileptic drugs. The objective of our review is to highlight the immunological features of the pathogenesis of seizures and to analyze possible immunotherapeutic approaches for drug resistant epilepsies that can alter the immune-mediated pathogenesis.
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Affiliation(s)
- Giovanna Vitaliti
- Department of Paediatrics and Pediatric Acute and Emergency Unit; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
| | - Piero Pavone
- Department of Paediatrics and Pediatric Acute and Emergency Unit; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
| | - Fahad Mahmood
- University London College Medical School; University of London; London, UK
| | - Giuseppe Nunnari
- Department of Infectious Diseases; Garibaldi Nesima Hospital; University of Catania; Catania, Italy
| | - Raffaele Falsaperla
- Department of Paediatrics and Pediatric Acute and Emergency Unit; Policlinico-Vittorio Emanuele University Hospital; University of Catania; Catania, Italy
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250
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Michalovicz LT, Konat GW. Peripherally restricted acute phase response to a viral mimic alters hippocampal gene expression. Metab Brain Dis 2014; 29:75-86. [PMID: 24363211 PMCID: PMC4343041 DOI: 10.1007/s11011-013-9471-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 12/13/2013] [Indexed: 11/26/2022]
Abstract
We have previously shown that peripherally restricted acute phase response (APR) elicited by intraperitoneal (i.p.) injection of a viral mimic, polyinosinic-polycytidylic acid (PIC), renders the brain hypersusceptible to excitotoxic insult as seen from profoundly exacerbated kainic acid (KA)-induced seizures. In the present study, we found that this hypersusceptibility was protracted for up to 72 h. RT-PCR profiling of hippocampal gene expression revealed rapid upregulation of 23 genes encoding cytokines, chemokines and chemokine receptors generally within 6 h after PIC challenge. The expression of most of these genes decreased by 24 h. However, two chemokine genes, i.e., Ccl19 and Cxcl13 genes, as well as two chemokine receptor genes, Ccr1 and Ccr7, remained upregulated for 72 h suggesting their possible involvement in the induction and sustenance of seizure hypersusceptibility. Also, 12 genes encoding proteins related to glutamatergic and GABAergic neurotransmission featured initial upregulation or downregulation followed by gradual normalization. The upregulation of the Gabrr3 gene remained upregulated at 72 h, congruent with its plausible role in the hypersusceptible phenotype. Moreover, the expression of ten microRNAs (miRs) was rapidly affected by PIC challenge, but their levels generally exhibited oscillating profiles over the time course of seizure hypersusceptibility. These results indicate that protracted seizure susceptibility following peripheral APR is associated with a robust polygenic response in the hippocampus.
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