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Cocozza G, Garofalo S, Capitani R, D’Alessandro G, Limatola C. Microglial Potassium Channels: From Homeostasis to Neurodegeneration. Biomolecules 2021; 11:1774. [PMID: 34944418 PMCID: PMC8698630 DOI: 10.3390/biom11121774] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/21/2022] Open
Abstract
The growing interest in the role of microglia in the progression of many neurodegenerative diseases is developing in an ever-expedited manner, in part thanks to emergent new tools for studying the morphological and functional features of the CNS. The discovery of specific biomarkers of the microglia phenotype could find application in a wide range of human diseases, and creates opportunities for the discovery and development of tailored therapeutic interventions. Among these, recent studies highlight the pivotal role of the potassium channels in regulating microglial functions in physiological and pathological conditions such as Alzheimer's Disease, Parkinson's Disease, and Amyotrophic Lateral Sclerosis. In this review, we summarize the current knowledge of the involvement of the microglial potassium channels in several neurodegenerative diseases and their role as modulators of microglial homeostasis and dysfunction in CNS disorders.
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Affiliation(s)
- Germana Cocozza
- Instituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, 86077 Pozzilli, Italy; (G.C.); (G.D.)
| | - Stefano Garofalo
- Department of Physiology and Pharmacology, Sapienza University of Rome, 00185 Rome, Italy; (S.G.); (R.C.)
| | - Riccardo Capitani
- Department of Physiology and Pharmacology, Sapienza University of Rome, 00185 Rome, Italy; (S.G.); (R.C.)
| | - Giuseppina D’Alessandro
- Instituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, 86077 Pozzilli, Italy; (G.C.); (G.D.)
- Department of Physiology and Pharmacology, Sapienza University of Rome, 00185 Rome, Italy; (S.G.); (R.C.)
| | - Cristina Limatola
- Instituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, 86077 Pozzilli, Italy; (G.C.); (G.D.)
- Department of Physiology and Pharmacology, Laboratory Affiliated to Istituto Pasteur Italia, Sapienza University of Rome, 00185 Rome, Italy
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de Curtis M, Rossetti AO, Verde DV, van Vliet EA, Ekdahl CT. Brain pathology in focal status epilepticus: evidence from experimental models. Neurosci Biobehav Rev 2021; 131:834-846. [PMID: 34517036 DOI: 10.1016/j.neubiorev.2021.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 09/02/2021] [Accepted: 09/05/2021] [Indexed: 12/01/2022]
Abstract
Status Epilepticus (SE) is often a neurological emergency characterized by abnormally sustained, longer than habitual seizures. The new ILAE classification reports that SE "…can have long-term consequences including neuronal death, neuronal injury…depending on the type and duration of seizures". While it is accepted that generalized convulsive SE exerts detrimental effects on the brain, it is not clear if other forms of SE, such as focal non-convulsive SE, leads to brain pathology and contributes to long-term deficits in patients. With the available clinical and experimental data, it is hard to discriminate the specific action of the underlying SE etiologies from that exerted by epileptiform activity. This information is highly relevant in the clinic for better treatment stratification, which may include both medical and surgical intervention for seizure control. Here we review experimental studies of focal SE, with an emphasis on focal non-convulsive SE. We present a repertoire of brain pathologies observed in the most commonly used animal models and attempt to establish a link between experimental findings and human condition(s). The extensive literature on focal SE animal models suggest that the current approaches have significant limitations in terms of translatability of the findings to the clinic. We highlight the need for a more stringent description of SE features and brain pathology in experimental studies in animal models, to improve the accuracy in predicting clinical translation.
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Affiliation(s)
- Marco de Curtis
- Epilepsy Unit, Fondazione IRCCS Istituto NeurologicoCarlo Besta, Milano, Italy.
| | - Andrea O Rossetti
- Department of Clinical Neuroscience, University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| | - Diogo Vila Verde
- Epilepsy Unit, Fondazione IRCCS Istituto NeurologicoCarlo Besta, Milano, Italy
| | - Erwin A van Vliet
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Science Park 904, P.O. Box 94246, 1090 GE, Amsterdam, the Netherlands; Amsterdam UMC, University of Amsterdam, Department of (Neuro)Pathology, Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, the Netherlands
| | - Christine T Ekdahl
- Division of Clinical Neurophysiology, Lund University, Sweden; Lund Epilepsy Center, Dept Clinical Sciences, Lund University, Sweden
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Wan Y, Feng B, You Y, Yu J, Xu C, Dai H, Trapp BD, Shi P, Chen Z, Hu W. Microglial Displacement of GABAergic Synapses Is a Protective Event during Complex Febrile Seizures. Cell Rep 2021; 33:108346. [PMID: 33147450 DOI: 10.1016/j.celrep.2020.108346] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 06/08/2020] [Accepted: 10/13/2020] [Indexed: 11/26/2022] Open
Abstract
Complex febrile seizures (FSs) lead to a high risk of intractable temporal lobe epilepsy during adulthood, yet the pathological process of complex FSs is largely unknown. Here, we demonstrate that activated microglia extensively associated with glutamatergic neuronal soma displace surrounding GABAergic presynapses in complex FSs. Patch-clamp electrophysiology establishes that the microglial displacement of GABAergic presynapses abrogates a complex-FS-induced increase in GABAergic neurotransmission and neuronal excitability, whereas GABA exerts an excitatory action in this immature stage. Pharmacological inhibition of microglial displacement of GABAergic presynapses or selective ablation of microglia in CD11bDTR mice promotes the generation of complex FSs. Blocking or deleting the P2Y12 receptor (P2Y12R) reduces microglial displacement of GABAergic presynapses and shortens the latency of complex FSs. Together, microglial displacement of GABAergic presynapses, regulated by P2Y12R, reduces neuronal excitability to mitigate the generation of complex FSs. Microglial displacement is a protective event during the pathological process of complex FSs.
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Affiliation(s)
- Yushan Wan
- Department of Pharmacology and Department of Pharmacy of Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, People's Republic of China
| | - Bo Feng
- Department of Pharmacology and Department of Pharmacy of Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, People's Republic of China
| | - Yi You
- Department of Pharmacology and Department of Pharmacy of Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, People's Republic of China
| | - Jie Yu
- Laboratory of Brain Function and Disease in Chinese Medicine, College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Cenglin Xu
- Department of Pharmacology and Department of Pharmacy of Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, People's Republic of China
| | - Haibin Dai
- Department of Pharmacology and Department of Pharmacy of Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, People's Republic of China
| | - Bruce D Trapp
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Peng Shi
- Department of Pharmacology and Department of Pharmacy of Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, People's Republic of China
| | - Zhong Chen
- Department of Pharmacology and Department of Pharmacy of Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, People's Republic of China; Laboratory of Brain Function and Disease in Chinese Medicine, College of Basic Medical Science, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China; Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
| | - Weiwei Hu
- Department of Pharmacology and Department of Pharmacy of Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, People's Republic of China.
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Palomba NP, Martinello K, Cocozza G, Casciato S, Mascia A, Di Gennaro G, Morace R, Esposito V, Wulff H, Limatola C, Fucile S. ATP-evoked intracellular Ca 2+ transients shape the ionic permeability of human microglia from epileptic temporal cortex. J Neuroinflammation 2021; 18:44. [PMID: 33588880 PMCID: PMC7883449 DOI: 10.1186/s12974-021-02096-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/02/2021] [Indexed: 12/18/2022] Open
Abstract
Background Intracellular Ca2+ modulates several microglial activities, such as proliferation, migration, phagocytosis, and inflammatory mediator secretion. Extracellular ATP, the levels of which significantly change during epileptic seizures, activates specific receptors leading to an increase of intracellular free Ca2+ concentration ([Ca2+]i). Here, we aimed to functionally characterize human microglia obtained from cortices of subjects with temporal lobe epilepsy, focusing on the Ca2+-mediated response triggered by purinergic signaling. Methods Fura-2 based fluorescence microscopy was used to measure [Ca2+]i in primary cultures of human microglial cells obtained from surgical specimens. The perforated patch-clamp technique, which preserves the cytoplasmic milieu, was used to measure ATP-evoked Ca2+-dependent whole-cell currents. Results In human microglia extracellular ATP evoked [Ca2+]i increases depend on Ca2+ entry from the extracellular space and on Ca2+ mobilization from intracellular compartments. Extracellular ATP also induced a transient fivefold potentiation of the total transmembrane current, which was completely abolished when [Ca2+]i increases were prevented by removing external Ca2+ and using an intracellular Ca2+ chelator. TRAM-34, a selective KCa3.1 blocker, significantly reduced the ATP-induced current potentiation but did not abolish it. The removal of external Cl− in the presence of TRAM-34 further lowered the ATP-evoked effect. A direct comparison between the ATP-evoked mean current potentiation and mean Ca2+ transient amplitude revealed a linear correlation. Treatment of microglial cells with LPS for 48 h did not prevent the ATP-induced Ca2+ mobilization but completely abolished the ATP-mediated current potentiation. The absence of the Ca2+-evoked K+ current led to a less sustained ATP-evoked Ca2+ entry, as shown by the faster Ca2+ transient kinetics observed in LPS-treated microglia. Conclusions Our study confirms a functional role for KCa3.1 channels in human microglia, linking ATP-evoked Ca2+ transients to changes in membrane conductance, with an inflammation-dependent mechanism, and suggests that during brain inflammation the KCa3.1-mediated microglial response to purinergic signaling may be reduced. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-021-02096-0.
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Affiliation(s)
| | | | | | | | | | | | | | - Vincenzo Esposito
- IRCCS Neuromed, Pozzilli, IS, Italy.,Department of Human Neurosciences, Sapienza Rome University, Rome, Italy
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Cristina Limatola
- IRCCS Neuromed, Pozzilli, IS, Italy.,Department of Physiology and Pharmacology "V. Erspamer", Sapienza Rome University, Rome, Italy
| | - Sergio Fucile
- IRCCS Neuromed, Pozzilli, IS, Italy.,Department of Physiology and Pharmacology "V. Erspamer", Sapienza Rome University, Rome, Italy
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Abstract
Protein Kinase A-Mediated Suppression of the Slow After Hyperpolarizing KCa3.1 Current in Temporal Lobe Epilepsy Tiwari MN, Mohan S, Biala Y, Yaari Y. J Neurosci . 2019;39(50):9914-9926. doi: https://doi.org/10.1523/JNEUROSCI.1603-19 . Brain insults, such as trauma, stroke, anoxia, and status epilepticus (SE), cause multiple changes in synaptic function and intrinsic properties of surviving neurons that may lead to the development of epilepsy. Experimentally, a single SE episode, induced by the convulsant pilocarpine, initiates the development of an epileptic condition resembling human temporal lobe epilepsy (TLE). Principal hippocampal neurons from such epileptic animals display enhanced spike output in response to excitatory stimuli compared with neurons from nonepileptic animals. This enhanced firing is negatively related to the size of the slow afterhyperpolarization (sAHP), which is reduced in the epileptic neurons. The sAHP is an intrinsic neuronal negative feedback mechanism consisting normally of 2 partially overlapping components produced by disparate mechanisms. One component is generated by activation of Ca2+-gated K+ (KCa) channels, likely KCa3.1, consequent to spike Ca2+ influx (the KCa-sAHP component). The second component is generated by enhancement of the electrogenic Na+/K+ ATPase (NKA) by spike Na+ influx (NKA-sAHP component). Here we show that the KCa-sAHP component is markedly reduced in male rat epileptic neurons, whereas the NKA-sAHP component is not altered. The KCa-sAHP reduction is due to the downregulation of KCa3.1 channels, mediated by cAMP-dependent protein kinase A (PKA). This sustained effect can be acutely reversed by applying PKA inhibitors, leading also to normalization of the spike output of epileptic neurons. We propose that the novel “acquired channelopathy” described here, namely, PKA-mediated downregulation of KCa3.1 activity, provides an innovative target for developing new treatments for TLE, hopefully overcoming the pharmacoresistance to traditional drugs. Significance Statement: Epilepsy, a common neurological disorder, often develops following a brain insult. Identifying key molecular and cellular mechanisms underlying acquired epilepsy is critical for developing effective antiepileptic therapies. In an experimental model of acquired epilepsy, we show that principal hippocampal neurons become intrinsically hyperexcitable. This alteration is due predominantly to the downregulation of a ubiquitous class of potassium ion channels, KCa3.1, whose main function is to dampen neuronal excitability. KCa3.1 downregulation is mediated by the cAMP-dependent PKA signaling pathway. Most importantly, it can be acutely reversed by PKA inhibitors, leading to recovery of KCa3.1 function and normalization of neuronal excitability. The discovery of this novel epileptogenic mechanism hopefully will facilitate the development of more efficient pharmacotherapy for acquired epilepsy.
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Nowakowska M, Gualtieri F, von Rüden EL, Hansmann F, Baumgärtner W, Tipold A, Potschka H. Profiling the Expression of Endoplasmic Reticulum Stress Associated Heat Shock Proteins in Animal Epilepsy Models. Neuroscience 2019; 429:156-172. [PMID: 31887356 DOI: 10.1016/j.neuroscience.2019.12.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 02/06/2023]
Abstract
Unfolded protein response is a signaling cascade triggered by misfolded proteins in the endoplasmic reticulum. Heat shock protein H4 (HSPH4) and A5 (HSPA5) are two chaperoning proteins present within the organelle, which target misfolded peptides during prolonged stress conditions. Epileptogenic insults and epileptic seizures are a notable source of stress on cells. To investigate whether they influence expression of these chaperones, we performed immunohistochemical stainings in brains from rats that experienced a status epilepticus (SE) as a trigger of epileptogenesis and from canine epilepsy patients. Quantification of HSPA5 and HSPH4 revealed alterations in hippocampus and parahippocampal cortex. In rats, SE induced up-regulation of HSPA5 in the piriform cortex and down-regulation of HSPA5 and HSPH4 in the hippocampus. Regionally restricted increases in expression of the two proteins has been observed in the chronic phase with spontaneous recurrent seizures. Confocal microscopy revealed a predominant expression of both proteins in neurons, no expression in microglia and circumscribed expression in astroglia. In canine patients, only up-regulation of HSPH4 expression was observed in Cornu Ammonis 1 region in animals diagnosed with structural epilepsy. This characterization of HSPA5 and HSPH4 expression provided extensive information regarding spatial and temporal alterations of the two proteins during SE-induced epileptogenesis and following epilepsy manifestations. Up-regulation of both proteins implies stress exerted on ER during these disease phases. Taken together suggest a differential impact of epileptogenesis on HSPA5 and HSPH4 expression and indicate them as a possible target for pharmacological modulation of unfolded protein response.
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Affiliation(s)
- Marta Nowakowska
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University Munich, Germany
| | - Fabio Gualtieri
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University Munich, Germany
| | - Eva-Lotta von Rüden
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University Munich, Germany
| | - Florian Hansmann
- Department of Pathology, University of Veterinary Medicine Hannover, Germany
| | | | - Andrea Tipold
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University Munich, Germany.
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Gualtieri F, Nowakowska M, von Rüden EL, Seiffert I, Potschka H. Epileptogenesis-Associated Alterations of Heat Shock Protein 70 in a Rat Post-Status Epilepticus Model. Neuroscience 2019; 415:44-58. [DOI: 10.1016/j.neuroscience.2019.06.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 06/18/2019] [Accepted: 06/25/2019] [Indexed: 02/02/2023]
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8
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Keck M, van Dijk RM, Deeg CA, Kistler K, Walker A, von Rüden EL, Russmann V, Hauck SM, Potschka H. Proteomic profiling of epileptogenesis in a rat model: Focus on cell stress, extracellular matrix and angiogenesis. Neurobiol Dis 2018; 112:119-135. [PMID: 29413716 DOI: 10.1016/j.nbd.2018.01.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 01/11/2018] [Accepted: 01/17/2018] [Indexed: 12/26/2022] Open
Abstract
Information about epileptogenesis-associated changes in protein expression patterns is of particular interest for future selection of target and biomarker candidates. Bioinformatic analysis of proteomic data sets can increase our knowledge about molecular alterations characterizing the different phases of epilepsy development following an initial epileptogenic insult. Here, we report findings from a focused analysis of proteomic data obtained for the hippocampus and parahippocampal cortex samples collected during the early post-insult phase, latency phase, and chronic phase of a rat model of epileptogenesis. The study focused on proteins functionally associated with cell stress, cell death, extracellular matrix (ECM) remodeling, cell-ECM interaction, cell-cell interaction, angiogenesis, and blood-brain barrier function. The analysis revealed prominent pathway enrichment providing information about the complex expression alterations of the respective protein groups. In the hippocampus, the number of differentially expressed proteins declined over time during the course of epileptogenesis. In contrast, a peak in the regulation of proteins linked with cell stress and death as well as ECM and cell-cell interaction became evident at later phases during epileptogenesis in the parahippocampal cortex. The data sets provide valuable information about the time course of protein expression patterns during epileptogenesis for a series of proteins. Moreover, the findings provide comprehensive novel information about expression alterations of proteins that have not been discussed yet in the context of epileptogenesis. These for instance include different members of the lamin protein family as well as the fermitin family member 2 (FERMT2). Induction of FERMT2 and other selected proteins, CD18 (ITGB2), CD44 and Nucleolin were confirmed by immunohistochemistry. Taken together, focused bioinformatic analysis of the proteomic data sets completes our knowledge about molecular alterations linked with cell death and cellular plasticity during epileptogenesis. The analysis provided can guide future selection of target and biomarker candidates.
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Affiliation(s)
- Michael Keck
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Roelof Maarten van Dijk
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Cornelia A Deeg
- Institute of Animal Physiology, Department of Veterinary Sciences, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Katharina Kistler
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Andreas Walker
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Eva-Lotta von Rüden
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Vera Russmann
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Stefanie M Hauck
- Research Unit Protein Science, Helmholtz Center Munich, Neuherberg, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany.
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Liu X, Quan N. Microglia and CNS Interleukin-1: Beyond Immunological Concepts. Front Neurol 2018; 9:8. [PMID: 29410649 PMCID: PMC5787061 DOI: 10.3389/fneur.2018.00008] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/05/2018] [Indexed: 12/12/2022] Open
Abstract
Activation of microglia and expression of the inflammatory cytokine interleukin-1 (IL-1) in the CNS have become almost synonymous with neuroinflammation. In numerous studies, increased CNS IL-1 expression and altered microglial morphology have been used as hallmarks of CNS inflammation. A central concept of how CNS IL-1 and microglia influence functions of the nervous system was derived from the notion initially generated in the peripheral immune system: IL-1 stimulates monocyte/macrophage (the peripheral counterparts of microglia) to amplify inflammation. It is increasingly clear, however, CNS IL-1 acts on other targets in the CNS and microglia participates in many neural functions that are not related to immunological activities. Further, CNS exhibits immunological privilege (although not as absolute as previously thought), rendering amplification of inflammation within CNS under stringent control. This review will analyze current literature to evaluate the contribution of immunological and non-immunological aspects of microglia/IL-1 interaction in the CNS to gain insights for how these aspects might affect health and disease in the nervous tissue.
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Affiliation(s)
- Xiaoyu Liu
- College of Medicine, Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, United States
| | - Ning Quan
- College of Medicine, Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, United States.,Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, United States
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10
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Keck M, Fournier A, Gualtieri F, Walker A, von Rüden EL, Russmann V, Deeg CA, Hauck SM, Krause R, Potschka H. A systems level analysis of epileptogenesis-associated proteome alterations. Neurobiol Dis 2017; 105:164-178. [PMID: 28576708 DOI: 10.1016/j.nbd.2017.05.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 05/22/2017] [Accepted: 05/29/2017] [Indexed: 12/18/2022] Open
Abstract
Despite intense research efforts, the knowledge about the mechanisms of epileptogenesis and epilepsy is still considered incomplete and limited. However, an in-depth understanding of molecular pathophysiological processes is crucial for the rational selection of innovative biomarkers and target candidates. Here, we subjected proteomic data from different phases of a chronic rat epileptogenesis model to a comprehensive systems level analysis. Weighted Gene Co-expression Network analysis identified several modules of interconnected protein groups reflecting distinct molecular aspects of epileptogenesis in the hippocampus and the parahippocampal cortex. Characterization of these modules did not only further validate the data but also revealed regulation of molecular processes not described previously in the context of epilepsy development. The data sets also provide valuable information about temporal patterns, which should be taken into account for development of preventive strategies in particular when it comes to multi-targeting network pharmacology approaches. In addition, principal component analysis suggests candidate biomarkers, which might inform the design of novel molecular imaging approaches aiming to predict epileptogenesis during different phases or confirm epilepsy manifestation. Further studies are necessary to distinguish between molecular alterations, which correlate with epileptogenesis versus those reflecting a mere consequence of the status epilepticus.
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Affiliation(s)
- Michael Keck
- Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University (LMU), 80539 Munich, Germany
| | - Anna Fournier
- Bioinformatics Core, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, 4367 Belvaux, Luxembourg
| | - Fabio Gualtieri
- Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University (LMU), 80539 Munich, Germany
| | - Andreas Walker
- Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University (LMU), 80539 Munich, Germany
| | - Eva-Lotta von Rüden
- Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University (LMU), 80539 Munich, Germany
| | - Vera Russmann
- Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University (LMU), 80539 Munich, Germany
| | - Cornelia A Deeg
- Institute of Animal Physiology, Department of Veterinary Sciences, Ludwig-Maximilians-University (LMU), 80539 Munich, Germany; Experimental Ophthalmology, Philipps University of Marburg, 35037 Marburg, Germany
| | - Stefanie M Hauck
- Research Unit Protein Science, Helmholtz Center Munich, 85764 Neuherberg, Germany
| | - Roland Krause
- Bioinformatics Core, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, 4367 Belvaux, Luxembourg.
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximilians-University (LMU), 80539 Munich, Germany.
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11
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Dale E, Staal RGW, Eder C, Möller T. KCa 3.1-a microglial target ready for drug repurposing? Glia 2016; 64:1733-41. [PMID: 27121595 DOI: 10.1002/glia.22992] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 03/29/2016] [Accepted: 04/03/2016] [Indexed: 01/25/2023]
Abstract
Over the past decade, glial cells have attracted attention for harboring unexploited targets for drug discovery. Several glial targets have attracted de novo drug discovery programs, as highlighted in this GLIA Special Issue. Drug repurposing, which has the objective of utilizing existing drugs as well as abandoned, failed, or not yet pursued clinical development candidates for new indications, might provide a faster opportunity to bring drugs for glial targets to patients with unmet needs. Here, we review the potential of the intermediate-conductance calcium-activated potassium channels KCa 3.1 as the target for such a repurposing effort. We discuss the data on KCa 3.1 expression on microglia in vitro and in vivo and review the relevant literature on the two KCa 3.1 inhibitors TRAM-34 and Senicapoc. Finally, we provide an outlook of what it might take to harness the potential of KCa 3.1 as a bona fide microglial drug target. GLIA 2016;64:1733-1741.
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Affiliation(s)
- Elena Dale
- Neuroinflammation Disease Biology Unit, Lundbeck Research USA, Paramus, New Jersey
| | - Roland G W Staal
- Neuroinflammation Disease Biology Unit, Lundbeck Research USA, Paramus, New Jersey
| | - Claudia Eder
- Institute for Infection and Immunity, St. George's, University of London, United Kingdom
| | - Thomas Möller
- Neuroinflammation Disease Biology Unit, Lundbeck Research USA, Paramus, New Jersey
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12
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Walker A, Russmann V, Deeg CA, von Toerne C, Kleinwort KJH, Szober C, Rettenbeck ML, von Rüden EL, Goc J, Ongerth T, Boes K, Salvamoser JD, Vezzani A, Hauck SM, Potschka H. Proteomic profiling of epileptogenesis in a rat model: Focus on inflammation. Brain Behav Immun 2016; 53:138-158. [PMID: 26685804 DOI: 10.1016/j.bbi.2015.12.007] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 11/27/2015] [Accepted: 12/10/2015] [Indexed: 01/13/2023] Open
Abstract
Detailed knowledge about the patterns of molecular alterations during epileptogenesis is a presupposition for identifying targets for preventive or disease-modifying approaches, as well as biomarkers of the disease. Large-scale differential proteome analysis can provide unique and novel perspectives based on comprehensive data sets informing about the complex regulation patterns in the disease proteome. Thus, we have completed an elaborate differential proteome analysis based on label-free LC-MS/MS in a rat model of epileptogenesis. Hippocampus and parahippocampal cortex tissues were sampled and analyzed separately at three key time points chosen for monitoring disease development following electrically-induced status epilepticus, namely, the early post-insult phase, the latency phase, and the chronic phase with spontaneous recurrent seizures. We focused the bioinformatics analysis on proteins linked to immune and inflammatory responses, because of the emerging evidence of the specific pathogenic role of inflammatory signalings during epileptogenesis. In the early post-insult and the latency phases, pathway enrichment analysis revealed an extensive over-representation of Toll-like receptor signaling, pro-inflammatory cytokines, heat shock protein regulation, and transforming growth factor beta signaling and leukocyte transendothelial migration. The inflammatory response in the chronic phase proved to be more moderate with differential expression in the parahippocampal cortex exceeding that in the hippocampus. The data sets provide novel information about numerous differentially expressed proteins, which serve as interaction partners or modulators in key disease-associated inflammatory signaling events. Noteworthy, a set of proteins which act as modulators of the ictogenic Toll-like receptor signaling proved to be differentially expressed. In addition, we report novel data demonstrating the regulation of different Toll-like receptor ligands during epileptogenesis. Taken together, the findings deepen our understanding of modulation of inflammatory signaling during epileptogenesis providing an excellent and comprehensive basis for the identification of target and biomarker candidates.
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Affiliation(s)
- Andreas Walker
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Vera Russmann
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Cornelia A Deeg
- Institute of Animal Physiology, Department of Veterinary Sciences, Ludwig-Maximilians-University (LMU), Munich, Germany; Experimental Ophthalmology, University of Marburg, Marburg, Germany
| | | | - Kristina J H Kleinwort
- Institute of Animal Physiology, Department of Veterinary Sciences, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Christoph Szober
- Institute of Animal Physiology, Department of Veterinary Sciences, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Maruja L Rettenbeck
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Eva-Lotta von Rüden
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Joanna Goc
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Tanja Ongerth
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Katharina Boes
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Josephine D Salvamoser
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Annamaria Vezzani
- IRCCS - Istituto di Ricerche Farmacologiche "Mario Negri", Department of Neuroscience, Milano, Italy
| | - Stefanie M Hauck
- Research Unit Protein Science, Helmholtz Center Munich, Neuherberg, Germany.
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany.
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Boes K, Russmann V, Ongerth T, Licko T, Salvamoser JD, Siegl C, Potschka H. Expression regulation and targeting of the peroxisome proliferator-activated receptor γ following electrically-induced status epilepticus. Neurosci Lett 2015; 604:151-6. [PMID: 26259695 DOI: 10.1016/j.neulet.2015.08.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 07/29/2015] [Accepted: 08/04/2015] [Indexed: 10/23/2022]
Abstract
The neuroprotective and anti-inflammatory effects of the peroxisome proliferator-activated receptor γ (PPARγ) agonist rosiglitazone are of particular interest for disease-modifying and antiepileptogenic approaches. We studied the expression of PPARγ and the impact of rosiglitazone on the consequences of status epilepticus (SE) in a rat post-SE model. Immunohistochemical analysis revealed a selective overexpression of PPARγ in the piriform cortex of rats with spontaneous seizures. Rosiglitazone administration initiated following SE failed to exert relevant effects on the development of spontaneous seizures and neuronal cell loss. Whereas spatial learning in the Morris water maze was delayed in SE animals with vehicle administration, the learning curve of rosiglitazone-treated SE rats showed no significant difference to that of controls. The study provides first evidence arguing against a robust antiepileptogenic effect. However, the findings in the spatial learning paradigm indicate disease-modifying effects.
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Affiliation(s)
- Katharina Boes
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Vera Russmann
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Tanja Ongerth
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Thomas Licko
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Josephine D Salvamoser
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Claudia Siegl
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany.
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14
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Lin H, Zheng C, Li J, Yang C, Hu L. Ca2+ -activated K+ channel-3.1 blocker TRAM-34 alleviates murine allergic rhinitis. Int Immunopharmacol 2015; 23:642-8. [PMID: 25466273 DOI: 10.1016/j.intimp.2014.10.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 09/21/2014] [Accepted: 10/17/2014] [Indexed: 01/08/2023]
Abstract
The precise pathogenesis of allergic rhinitis (AR) remains unclear and AR is less easily cured. Recent evidence has suggested that calcium-activated K+ channel-3.1(KCa3.1) is implicated in the immune response of allergic and inflammatory diseases and TRAM-34 is a selective KCa3.1 blocker. However, little is known about its role in AR. We aimed to investigate the effect of TRAM-34 in a mouse model of AR induced by ovalbumin (OVA). The BALB/c mice were divided into six groups: untreated AR group, 200 μg TRAM-34 treated AR group, 400 μg TRAM-34 treated AR group, 200 μg TRAM-34 treated normal group, 400 μg TRAM-34 treated normal group and untreated normal control group. Histopathological characteristics were assessed by HE staining. KCa3.1 protein expression was investigated by immunohistochemistry and western blotting method, and mRNA expression of KCa3.1, stromal interaction molecule1 (STIM1) and Orai1 in nasal tissues were assessed by real-time PCR. Furthermore, concentrations of OVA-specific IgE, ECP, IL-4, IL-5, IL-17 and IL-1β in nasal lavage fluid (NLF) were analyzed by enzyme-linked immunosorbent assay (ELISA). Results showed that TRAM-34 administration into the nostril attenuated sneezing, nasal rubbing, epithelial cell proliferation, eosinophil infiltration and inhibited nasal mucosa KCa3.1, STIM1 and Orai1 expression in TRAM-34 treated mice compared with untreated AR mice and suppressed inflammatory cytokines in the NLF of TRAM-34 treated groups compared with untreated AR mice. In conclusion, TRAM-34 could effectively alleviate murine allergic rhinitis by suppressing KCa3.1 and leads to reduction of K+ efflux and Ca2 + influx, leading to inflammation reduction and allergic responses attenuation.
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15
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Rettenbeck ML, von Rüden EL, Bienas S, Carlson R, Stein VM, Tipold A, Potschka H. Microglial ROS production in an electrical rat post-status epilepticus model of epileptogenesis. Neurosci Lett 2015; 599:146-51. [PMID: 26007700 DOI: 10.1016/j.neulet.2015.05.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 04/30/2015] [Accepted: 05/20/2015] [Indexed: 11/26/2022]
Abstract
Reactive oxygen species and inflammatory signaling have been identified as pivotal pathophysiological factors contributing to epileptogenesis. Considering the development of combined anti-inflammatory and antioxidant treatment strategies with antiepileptogenic potential, a characterization of the time course of microglial reactive oxygen species generation during epileptogenesis is of major interest. Thus, we isolated microglia cells and analyzed the generation of reactive oxygen species by flow cytometric analysis in an electrical rat post-status epilepticus model. Two days post status epilepticus, a large-sized cell cluster exhibited a pronounced response with excessive production of reactive oxygen species upon stimulation with phorbol-myristate-acetate. Neither in the latency phase nor in the chronic phase with spontaneous seizures a comparable cell population with induction of reactive oxygen species was identified. We were able to demonstrate in the electrical rat post-status-epilepticus model, that microglial ROS generation reaches a peak after the initial insult, is only marginally increased in the latency phase, and returns to control levels during the chronic epileptic phase. The data suggest that a combination of anti-inflammatory and radical scavenging approaches might only be beneficial during a short time window after an epileptogenic brain insult.
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Affiliation(s)
- Maruja L Rettenbeck
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Eva-Lotta von Rüden
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Silvia Bienas
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Regina Carlson
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Veronika M Stein
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Andrea Tipold
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University, Munich, Germany.
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