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Jeong KH, Zhu J, Park S, Kim WJ. Transient Receptor Potential Vanilloid 6 Modulates Aberrant Axonal Sprouting in a Mouse Model of Pilocarpine-Induced Epilepsy. Mol Neurobiol 2024; 61:2839-2853. [PMID: 37940780 DOI: 10.1007/s12035-023-03748-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 10/26/2023] [Indexed: 11/10/2023]
Abstract
Transient receptor potential vanilloid 6 (TRPV6) is a highly selective calcium-ion channel that belongs to the TRPV family. TRPV6 is widely distributed in the brain, but its role in neurological diseases such as epilepsy remains unknown. Here, we report for the first time that TRPV6 expression is upregulated in the hippocampus of a pilocarpine-induced status epilepticus model, mainly in the suprapyramidal bundle of the mossy fiber (MF) projection of the hippocampal CA3 regions. We found that TRPV6 overexpression via viral vector transduction attenuated abnormal MF sprouting (MFS), whereas TRPV6 knockdown aggravated the development of MFS and the incidence of recurrent seizures during epileptogenic progression. In the in vitro experiments, our results showed that modulation of TRPV6 expression resulted in a change in axonal formation in cultured hippocampal neurons. In addition, we found that TRPV6 was implicated in the regulation of Akt-glycogen synthase kinase-3-β activity, which is closely related to the cellular mechanism of axonal outgrowth. Therefore, these findings suggest that TRPV6 may regulate the formation of aberrant synaptic circuits during epileptogenesis.
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Affiliation(s)
- Kyoung Hoon Jeong
- Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
| | - Jing Zhu
- Department of Neurology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Soojin Park
- Department of Neurology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Won-Joo Kim
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, 06273, Republic of Korea.
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2
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Liu M, Liu H, Feng F, Krook-Magnuson E, Dudley SC. TRPM7 kinase mediates hypomagnesemia-induced seizure-related death. Sci Rep 2023; 13:7855. [PMID: 37188671 DOI: 10.1038/s41598-023-34789-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 05/08/2023] [Indexed: 05/17/2023] Open
Abstract
Hypomagnesemia (HypoMg) can cause seizures and death, but the mechanism is unknown. Transient receptor potential cation channel subfamily M 7 (TRPM7) is a Mg transporter with both channel and kinase function. In this study, we focused on the kinase role of TRPM7 in HypoMg-induced seizures and death. Wild type C57BL/6J mice and transgenic mice with a global homozygous mutation in the TRPM7 kinase domain (TRPM7K1646R, with no kinase function) were fed with control diet or a HypoMg diet. After 6 weeks of HypoMg diet, mice had significantly decreased serum Mg, elevated brain TRPM7, and a significant rate of death, with females being most susceptible. Deaths were immediately preceded by seizure events. TRPM7K1646R mice showed resistance to seizure-induced death. HypoMg-induced brain inflammation and oxidative stress were suppressed by TRPM7K1646R. Compared to their male counterparts, HypoMg female mice had higher levels of inflammation and oxidative stress in the hippocampus. We concluded that TRPM7 kinase function contributes seizure-induced deaths in HypoMg mice and that inhibiting the kinase reduced inflammation and oxidative stress.
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Affiliation(s)
- Man Liu
- Cardiovascular Division, Department of Medicine, The Lillehei Heart Institute, University of Minnesota at Twin Cities, 2231 6th Street SE, CCRB 4-141, Minneapolis, MN, 55455, USA
| | - Hong Liu
- Cardiovascular Division, Department of Medicine, The Lillehei Heart Institute, University of Minnesota at Twin Cities, 2231 6th Street SE, CCRB 4-141, Minneapolis, MN, 55455, USA
| | - Feng Feng
- Cardiovascular Division, Department of Medicine, The Lillehei Heart Institute, University of Minnesota at Twin Cities, 2231 6th Street SE, CCRB 4-141, Minneapolis, MN, 55455, USA
| | - Esther Krook-Magnuson
- Department of Neuroscience, University of Minnesota at Twin Cities, Minneapolis, MN, USA
| | - Samuel C Dudley
- Cardiovascular Division, Department of Medicine, The Lillehei Heart Institute, University of Minnesota at Twin Cities, 2231 6th Street SE, CCRB 4-141, Minneapolis, MN, 55455, USA.
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3
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Abstract
Status epilepticus (SE) remains a significant cause of morbidity and mortality and often is refractory to standard first-line treatments. A rapid loss of synaptic inhibition and development of pharmacoresistance to benzodiazepines (BZDs) occurs early during SE, while NMDA and AMPA receptor antagonists remain effective treatments after BZDs have failed. Multimodal and subunit-selective receptor trafficking within minutes to an hour of SE involves GABA-A, NMDA, and AMPA receptors and contributes to shifts in the number and subunit composition of surface receptors with differential impacts on the physiology, pharmacology, and strength of GABAergic and glutamatergic currents at synaptic and extrasynaptic sites. During the first hour of SE, synaptic GABA-A receptors containing γ2 subunits move to the cell interior while extrasynaptic GABA-A receptors with δ subunits are preserved. Conversely, NMDA receptors containing N2B subunits are increased at synaptic and extrasynaptic sites, and homomeric GluA1 ("GluA2-lacking") calcium permeant AMPA receptor surface expression also is increased. Molecular mechanisms, largely driven by NMDA receptor or calcium permeant AMPA receptor activation early during circuit hyperactivity, regulate subunit-specific interactions with proteins involved with synaptic scaffolding, adaptin-AP2/clathrin-dependent endocytosis, endoplasmic reticulum (ER) retention, and endosomal recycling. Reviewed here is how SE-induced shifts in receptor subunit composition and surface representation increase the excitatory to inhibitory imbalance that sustains seizures and fuels excitotoxicity contributing to chronic sequela such as "spontaneous recurrent seizures" (SRS). A role for early multimodal therapy is suggested both for treatment of SE and for prevention of long-term comorbidities.
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Affiliation(s)
- David E Naylor
- VA Greater Los Angeles Healthcare System, Department of Neurology, David Geffen School of Medicine at UCLA, and The Lundquist Institute at Harbor-UCLA Medical Center, Los Angeles, California, USA
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4
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Bryson A, Reid C, Petrou S. Fundamental Neurochemistry Review: GABA A receptor neurotransmission and epilepsy: Principles, disease mechanisms and pharmacotherapy. J Neurochem 2023; 165:6-28. [PMID: 36681890 DOI: 10.1111/jnc.15769] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 12/12/2022] [Accepted: 01/04/2023] [Indexed: 01/23/2023]
Abstract
Epilepsy is a common neurological disorder associated with alterations of excitation-inhibition balance within brain neuronal networks. GABAA receptor neurotransmission is the most prevalent form of inhibitory neurotransmission and is strongly implicated in both the pathophysiology and treatment of epilepsy, serving as a primary target for antiseizure medications for over a century. It is now established that GABA exerts a multifaceted influence through an array of GABAA receptor subtypes that extends far beyond simply negating excitatory activity. As the role of GABAA neurotransmission within inhibitory circuits is elaborated, this will enable the development of precision therapies that correct the network dysfunction underlying epileptic pathology.
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Affiliation(s)
- Alexander Bryson
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.,Department of Neurology, Austin Health, Heidelberg, Victoria, Australia
| | - Christopher Reid
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Steven Petrou
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.,Praxis Precision Medicines, Inc., Cambridge, Massachusetts, USA
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5
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Fisch U, Jünger AL, Hert L, Rüegg S, Sutter R. Therapeutically induced EEG burst-suppression pattern to treat refractory status epilepticus—what is the evidence? Z Epileptol 2022. [DOI: 10.1007/s10309-022-00539-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractCurrent guidelines advocate to treat refractory status epilepticus (RSE) with continuously administered anesthetics to induce an artificial coma if first- and second-line antiseizure drugs have failed to stop seizure activity. A common surrogate for monitoring the depth of the artificial coma is the appearance of a burst-suppression pattern (BS) in the EEG. This review summarizes the current knowledge on the origin and neurophysiology of the BS phenomenon as well as the evidence from the literature for the presumed benefit of BS as therapy in adult patients with RSE.
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Belperio G, Corso C, Duarte CB, Mele M. Molecular Mechanisms of Epilepsy: The Role of the Chloride Transporter KCC2. J Mol Neurosci 2022. [PMID: 35819636 DOI: 10.1007/s12031-022-02041-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 06/07/2022] [Indexed: 10/17/2022]
Abstract
Epilepsy is a neurological disease characterized by abnormal or synchronous brain activity causing seizures, which may produce convulsions, minor physical signs, or a combination of symptoms. These disorders affect approximately 65 million people worldwide, from all ages and genders. Seizures apart, epileptic patients present a high risk to develop neuropsychological comorbidities such as cognitive deficits, emotional disturbance, and psychiatric disorders, which severely impair quality of life. Currently, the treatment for epilepsy includes the administration of drugs or surgery, but about 30% of the patients treated with antiepileptic drugs develop time-dependent pharmacoresistence. Therefore, further investigation about epilepsy and its causes is needed to find new pharmacological targets and innovative therapeutic strategies. Pharmacoresistance is associated to changes in neuronal plasticity and alterations of GABAA receptor-mediated neurotransmission. The downregulation of GABA inhibitory activity may arise from a positive shift in GABAA receptor reversal potential, due to an alteration in chloride homeostasis. In this paper, we review the contribution of K+-Cl--cotransporter (KCC2) to the alterations in the Cl- gradient observed in epileptic condition, and how these alterations are coupled to the increase in the excitability.
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7
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Vishwakarma S, Singh S, Singh TG. Pharmacological modulation of cytokines correlating neuroinflammatory cascades in epileptogenesis. Mol Biol Rep 2021; 49:1437-1452. [PMID: 34751915 DOI: 10.1007/s11033-021-06896-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 10/29/2021] [Indexed: 02/06/2023]
Abstract
Epileptic seizure-induced brain injuries include activation of neuroimmune response with activation of microglia, astrocytes cells releasing neurotoxic inflammatory mediators underlies the pathophysiology of epilepsy. A wide spectrum of neuroinflammatory pathways is involved in neurodegeneration along with elevated levels of inflammatory mediators indicating the neuroinflammation in the epileptic brain. Therefore, the neuroimmune response is commonly observed in the epileptic brain, indicating elevated cytokine levels, providing an understanding of the neuroinflammatory mechanism contributing to seizures recurrence. Clinical and experimental-based evidence suggested the elevated levels of cytokines responsible for neuronal excitation and blood-brain barrier (BBB) dysfunctioning causing the drug resistance in epilepsy. Therefore, the understanding of the pathogenesis of neuroinflammation in epilepsy, including migration of microglial cells releasing the inflammatory cytokines indicating the correlation of elevated levels of inflammatory mediators (interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) triggering the generation or recurrence of seizures. The current review summarized the knowledge regarding elevated inflammatory mediators as immunomodulatory response correlating multiple neuroinflammatory NF-kB, RIPK, MAPK, ERK, JNK, JAK-STAT signaling cascades in epileptogenesis. Further selective targeting of inflammatory mediators provides beneficial therapeutic strategies for epilepsy.
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Affiliation(s)
- Shubham Vishwakarma
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, 140401, India
| | - Shareen Singh
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, 140401, India
| | - Thakur Gurjeet Singh
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, 140401, India.
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Qin J, Wei T, Chen H, Lin X, Qin D, Wei F, Liu P, Ye W, Su J. Salicylate Induced GABAAR Internalization by Dopamine D1-Like Receptors Involving Protein Kinase C (PKC) in Spiral Ganglion Neurons. Med Sci Monit 2021; 27:e933278. [PMID: 34657931 PMCID: PMC8532520 DOI: 10.12659/msm.933278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Sodium salicylate (SS) induces excitotoxicity of spiral ganglion neurons (SGNs) by inhibiting the response of γ-aminobutyric acid type A receptors (GABAARs). Our previous studies have shown that SS can increase the internalization of GABAARs on SGNs, which involves dopamine D1-like receptors (D1Rs) and related signaling pathways. In this study, we aimed to explore the role of D1Rs and their downstream molecule protein kinase C (PKC) in the process of SS inhibiting GABAARs. MATERIAL AND METHODS The expression of D1Rs and GABARγ2 on rat cochlear SGNs cultured in vitro was tested by immunofluorescence. Then, the SGNs were exposed to SS, D1R agonist (SKF38393), D1R antagonist (SCH23390), clathrin/dynamin-mediated endocytosis inhibitor (dynasore), and PKC inhibitor (Bisindolylmaleimide I). Western blotting and whole-cell patch clamp technique were used to assess the changes of surface and total protein of GABARγ2 and GABA-activated currents. RESULTS Immunofluorescence showed that D1 receptors (DRD1) were expressed on SGNs. Data from western blotting showed that SS promoted the internalization of cell surface GABAARs, and activating D1Rs had the same result. Inhibiting D1Rs and PKC decreased the internalization of GABAARs. Meanwhile, the phosphorylation level of GABAARγ2 S327 affected by PKC was positively correlated with the degree of internalization of GABAARs. Moreover, whole-cell patch clamp recording showed that inhibition of D1Rs or co-inhibition of D1Rs and PKC attenuated the inhibitory effect of SS on GABA-activated currents. CONCLUSIONS D1Rs mediate the GABAAR internalization induced by SS via a PKC-dependent manner and participate in the excitotoxic process of SGNs.
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Affiliation(s)
- Jiangyuan Qin
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Tingjia Wei
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Huiying Chen
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Xiaoyu Lin
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Danxue Qin
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Fangyu Wei
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Peiqiang Liu
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Wenhua Ye
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Jiping Su
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
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9
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Mele M, Vieira R, Correia B, De Luca P, Duarte FV, Pinheiro PS, Duarte CB. Transient incubation of cultured hippocampal neurons in the absence of magnesium induces rhythmic and synchronized epileptiform-like activity. Sci Rep 2021; 11:11374. [PMID: 34059735 PMCID: PMC8167095 DOI: 10.1038/s41598-021-90486-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 04/29/2021] [Indexed: 11/09/2022] Open
Abstract
Cell culture models are important tools to study epileptogenesis mechanisms. The aim of this work was to characterize the spontaneous and synchronized rhythmic activity developed by cultured hippocampal neurons after transient incubation in zero Mg2+ to model Status Epilepticus. Cultured hippocampal neurons were transiently incubated with a Mg2+-free solution and the activity of neuronal networks was evaluated using single cell calcium imaging and whole-cell current clamp recordings. Here we report the development of synchronized and spontaneous [Ca2+]i transients in cultured hippocampal neurons immediately after transient incubation in a Mg2+-free solution. Spontaneous and synchronous [Ca2+]i oscillations were observed when the cells were then incubated in the presence of Mg2+. Functional studies also showed that transient incubation in Mg2+-free medium induces neuronal rhythmic burst activity that was prevented by antagonists of glutamate receptors. In conclusion, we report the development of epileptiform-like activity, characterized by spontaneous and synchronized discharges, in cultured hippocampal neurons transiently incubated in the absence of Mg2+. This model will allow studying synaptic alterations contributing to the hyperexcitability that underlies the development of seizures and will be useful in pharmacological studies for testing new drugs for the treatment of epilepsy.
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Affiliation(s)
- Miranda Mele
- CNC-Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal.,Institute for Interdisciplinary Research, Coimbra, Portugal
| | - Ricardo Vieira
- CNC-Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal
| | - Bárbara Correia
- CNC-Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal
| | - Pasqualino De Luca
- CNC-Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal.,Institute for Interdisciplinary Research, Coimbra, Portugal
| | - Filipe V Duarte
- CNC-Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal.,Institute for Interdisciplinary Research, Coimbra, Portugal
| | - Paulo S Pinheiro
- CNC-Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal.,Institute for Interdisciplinary Research, Coimbra, Portugal
| | - Carlos B Duarte
- CNC-Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal. .,Department of Life Sciences, University of Coimbra, Coimbra, Portugal.
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10
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Juvale IIA, Che Has AT. Possible interplay between the theories of pharmacoresistant epilepsy. Eur J Neurosci 2020; 53:1998-2026. [PMID: 33306252 DOI: 10.1111/ejn.15079] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 11/22/2020] [Accepted: 12/04/2020] [Indexed: 02/06/2023]
Abstract
Epilepsy is one of the oldest known neurological disorders and is characterized by recurrent seizure activity. It has a high incidence rate, affecting a broad demographic in both developed and developing countries. Comorbid conditions are frequent in patients with epilepsy and have detrimental effects on their quality of life. Current management options for epilepsy include the use of anti-epileptic drugs, surgery, or a ketogenic diet. However, more than 30% of patients diagnosed with epilepsy exhibit drug resistance to anti-epileptic drugs. Further, surgery and ketogenic diets do little to alleviate the symptoms of patients with pharmacoresistant epilepsy. Thus, there is an urgent need to understand the underlying mechanisms of pharmacoresistant epilepsy to design newer and more effective anti-epileptic drugs. Several theories of pharmacoresistant epilepsy have been suggested over the years, the most common being the gene variant hypothesis, network hypothesis, multidrug transporter hypothesis, and target hypothesis. In our review, we discuss the main theories of pharmacoresistant epilepsy and highlight a possible interconnection between their mechanisms that could lead to the development of novel therapies for pharmacoresistant epilepsy.
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Affiliation(s)
- Iman Imtiyaz Ahmed Juvale
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | - Ahmad Tarmizi Che Has
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia
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11
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Turovskaya MV, Epifanova EA, Tarabykin VS, Babaev AA, Turovsky EA. Interleukin-10 restores glutamate receptor-mediated Ca 2+-signaling in brain circuits under loss of Sip1 transcription factor. Int J Neurosci 2020; 132:114-125. [PMID: 32727246 DOI: 10.1080/00207454.2020.1803305] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE This study aimed to investigate the connection between the mutation of the Sip1 transcription factor and impaired Ca2+-signaling, which reflects changes in neurotransmission in the cerebral cortex in vitro. METHODS We used mixed neuroglial cortical cell cultures derived from Sip1 mutant mice. The cells were loaded with a fluorescent ratiometric calcium-sensitive probe Fura-2 AM and epileptiform activity was modeled by excluding magnesium ions from the external media or adding a GABA(A) receptor antagonist, bicuculline. Intracellular calcium dynamics were recorded using fluorescence microscopy. To identify the level of gene expression, the Real-Time PCR method was used. RESULTS It was found that cortical neurons isolated from homozygous (Sip1fl/fl) mice with the Sip1 mutation demonstrate suppressed Ca2+ signals in models of epileptiform activity in vitro. Wild-type cortical neurons are characterized by synchronous high-frequency and high-amplitude Ca2+ oscillations occurring in all neurons of the network in response to Mg2+-free medium and bicuculline. But cortical Sip1fl/fl neurons only single Ca2+ pulses or attenuated Ca2+ oscillations are recorded and only in single neurons, while most of the cell network does not respond to these stimuli. This signal deficiency of Sip1fl/fl neurons correlates with a suppressed expression level of the genes encoding the subunits of NMDA, AMPA, and KA receptors; protein kinases PKA, JNK, CaMKII; and also the transcription factor Hif1α. These negative effects were partially abolished when Sip1fl/fl neurons are grown in media with anti-inflammatory cytokine IL-10. IL-10 increases the expression of the above-mentioned genes but not to the level of expression in wild-type. At the same time, the amplitudes of Ca2+ signals increase in response to the selective agonists of NMDA, AMPA and KA receptors, and the proportion of neurons responding with Ca2+ oscillations to a Mg2+-free medium and bicuculline increases. CONCLUSION IL-10 restores neurotransmission in neuronal networks with the Sip1 mutation by regulating the expression of genes encoding signaling proteins.
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Affiliation(s)
- Maria V Turovskaya
- Laboratory of Intracellular Signaling, Institute of Cell Biophysics of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences," Russia
| | - Ekaterina A Epifanova
- Laboratory of Genetic Engineering Technologies, Lobachevsky State University of Nizhni Novgorod, Russia
| | - Victor S Tarabykin
- Laboratory of Genetic Engineering Technologies, Lobachevsky State University of Nizhni Novgorod, Russia
| | - Alexei A Babaev
- Laboratory of Genetic Engineering Technologies, Lobachevsky State University of Nizhni Novgorod, Russia
| | - Egor A Turovsky
- Laboratory of Intracellular Signaling, Institute of Cell Biophysics of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences," Russia.,Laboratory of Genetic Engineering Technologies, Lobachevsky State University of Nizhni Novgorod, Russia
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12
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Liu X, Geng J, Guo H, Zhao H, Ai Y. Propofol inhibited apoptosis of hippocampal neurons in status epilepticus through miR-15a-5p/NR2B/ERK1/2 pathway. Cell Cycle 2020; 19:1000-1011. [PMID: 32212891 DOI: 10.1080/15384101.2020.1743909] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Although a previous study reported that propofol had a therapeutic effect in status epilepticus (SE), the mechanisms underlying the effect of propofol in SE remain unclear. The aim of this study was to explore the regulatory mechanisms underlying propofol-induced inhibition of SE.A rat SE model was established using the lithium-pilocarpine injection method. A qRT-PCR and Western blot were utilized to detect the expression of relative molecules. Cell apoptosis was evaluated by a flow cytometry assay. The interaction between miR-15a-5p and NR2B was assessed using a luciferase reporter assay.Propofol inhibited cell apoptosis and increased miR-15a-5p expression both in hippocampal tissues of SE rats and low Mg2+-induced hippocampal neurons. Propofol-induced attenuation of apoptosis of low Mg2+-induced hippocampal neurons was mediated by miR-15a-5p. miR-15a-5p targeted NR2B and negatively regulated its expression. Propofol downregulated NR2B expression, mediated by miR-15a-5p. In terms of the mechanism of action, propofol suppressed the apoptosis of Mg2+-induced hippocampal neurons through the miR-15a-5p/NR2B/ERK1/2 pathway. In vivo experiment suggested that propofol inhibited the apoptosis of hippocampal neurons in SE rats by upregulating miR-15a-5p.In terms of the molecular mechanism of propofol, it appears to inhibit apoptosis of hippocampal neurons in SE through the miR-15a-5p/NR2B/ERK1/2 pathway. The findings provide theoretical support for propofol treatment of SE.
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Affiliation(s)
- Xing Liu
- Department of Anaesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jiefeng Geng
- Department of Neurosurgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Haiming Guo
- Department of Anaesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Huaping Zhao
- Department of Anaesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yanqiu Ai
- Department of Anaesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Gaidin SG, Zinchenko VP, Teplov IY, Tuleukhanov ST, Kosenkov AM. Epileptiform activity promotes decreasing of Ca 2+ conductivity of NMDARs, AMPARs, KARs, and voltage-gated calcium channels in Mg 2+-free model. Epilepsy Res 2019; 158:106224. [PMID: 31698280 DOI: 10.1016/j.eplepsyres.2019.106224] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 10/01/2019] [Accepted: 10/22/2019] [Indexed: 02/06/2023]
Abstract
NMDA, AMPA, and kainate receptors are the principal excitatory receptors in the brain. These receptors have been considered as the main targets in the treatment of epilepsy in recent years. This work aimed to determine how the Ca2+ conductivity of ionotropic glutamate receptors and voltage-gated Ca2+ channels changes in an in vitro model of epilepsy. For induction of epileptiform activity, hippocampal neurons were exposed to Mg2+-free medium. It has been shown that removal of Mg2+ from the medium not only removes the block from the NMDA receptors but also stimulates the release of glutamate in a way that is independent of the NMDA receptors. Under these conditions, the structure of the bursts significantly differs from the spontaneous bursts arising in mature hippocampal cultures. We have demonstrated that the frequency and amplitude of Mg2+-free medium-induced Ca2+ oscillations decrease after the 60-min exposure. Besides, the Ca2+ conductivity of ionotropic glutamate receptors and voltage-gated calcium channels significantly reduces. Thus, the decrease of Ca2+ conductivity can be considered as one of the mechanisms of adaptation during epilepsy.
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Naimo GD, Guarnaccia M, Sprovieri T, Ungaro C, Conforti FL, Andò S, Cavallaro S. A Systems Biology Approach for Personalized Medicine in Refractory Epilepsy. Int J Mol Sci 2019; 20:E3717. [PMID: 31366017 DOI: 10.3390/ijms20153717] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 07/22/2019] [Accepted: 07/28/2019] [Indexed: 02/01/2023] Open
Abstract
Epilepsy refers to a common chronic neurological disorder that affects all age groups. Unfortunately, antiepileptic drugs are ineffective in about one-third of patients. The complex interindividual variability influences the response to drug treatment rendering the therapeutic failure one of the most relevant problems in clinical practice also for increased hospitalizations and healthcare costs. Recent advances in the genetics and neurobiology of epilepsies are laying the groundwork for a new personalized medicine, focused on the reversal or avoidance of the pathophysiological effects of specific gene mutations. This could lead to a significant improvement in the efficacy and safety of treatments for epilepsy, targeting the biological mechanisms responsible for epilepsy in each individual. In this review article, we focus on the mechanism of the epilepsy pharmacoresistance and highlight the use of a systems biology approach for personalized medicine in refractory epilepsy.
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Liu Y, Wang H, Liu N, Du J, Lan X, Qi X, Zhuang C, Sun T, Li Y, Yu J. Oxymatrine protects neonatal rat against hypoxic-ischemic brain damage via PI3K/Akt/GSK3β pathway. Life Sci 2020; 254:116444. [PMID: 31102745 DOI: 10.1016/j.lfs.2019.04.070] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 04/27/2019] [Accepted: 04/30/2019] [Indexed: 12/22/2022]
Abstract
AIMS In this study we aimed to explore the specific effect and mechanism of oxymatrine on neonatal rats hypoxic-ischemic brain damage. MATERIALS AND METHODS Hypoxia-ischemia damage model was built by ligaturing the left common carotid artery in 7-day-old rat. Rat pups in OMT group received intraperitoneal injection with oxymatrine (120 mg/kg). Oxygen glucose deprivation/reperfusion model was created in hippocampal neurons. Neurological behavioral, histopathological alteration, cell viability, intracellular Ca2+ concentration, MMP and cell apoptosis were used in damage evaluation. KEY FINDINGS The results shown that oxymatrine regulated brain damage and cell apoptosis by controlling NR2B-PI3K/Akt/GSK3β signaling pathway. SIGNIFICANCE Neonatal hypoxic-ischemic brain damage is a destructive injury that leading to death and detrimental neurological deficits. Oxymatrine is a natural alkaloid compound that can alleviate the ischemic cerebral infarction. In the study, 120 mg/kg oxymatrine decreased neuroethology damage and neuronal damage in the cerebral cortex and the hippocampus CA3. Moreover, 0.2, 1, 5 μg/ml oxymatrine improved cell survival, decreased cell apoptosis. The utilization of LY293004 (PI3K signaling pathway inhibitor) also supported that oxymatrine ameliorated neonatal hypoxic-ischemic brain damage and cell injury by controlling NR2B-PI3K/Akt/GSK3β signaling pathway.
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Mele M, Costa RO, Duarte CB. Alterations in GABA A-Receptor Trafficking and Synaptic Dysfunction in Brain Disorders. Front Cell Neurosci 2019; 13:77. [PMID: 30899215 PMCID: PMC6416223 DOI: 10.3389/fncel.2019.00077] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 02/15/2019] [Indexed: 12/12/2022] Open
Abstract
GABAA receptors (GABAAR) are the major players in fast inhibitory neurotransmission in the central nervous system (CNS). Regulation of GABAAR trafficking and the control of their surface expression play important roles in the modulation of the strength of synaptic inhibition. Different pieces of evidence show that alterations in the surface distribution of GABAAR and dysregulation of their turnover impair the activity of inhibitory synapses. A diminished efficacy of inhibitory neurotransmission affects the excitatory/inhibitory balance and is a common feature of various disorders of the CNS characterized by an increased excitability of neuronal networks. The synaptic pool of GABAAR is mainly controlled through regulation of internalization, recycling and lateral diffusion of the receptors. Under physiological condition these mechanisms are finely coordinated to define the strength of GABAergic synapses. In this review article, we focus on the alteration in GABAAR trafficking with an impact on the function of inhibitory synapses in various disorders of the CNS. In particular we discuss how similar molecular mechanisms affecting the synaptic distribution of GABAAR and consequently the excitatory/inhibitory balance may be associated with a wide diversity of pathologies of the CNS, from psychiatric disorders to acute alterations leading to neuronal death. A better understanding of the cellular and molecular mechanisms that contribute to the impairment of GABAergic neurotransmission in these disorders, in particular the alterations in GABAAR trafficking and surface distribution, may lead to the identification of new pharmacological targets and to the development of novel therapeutic strategies.
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Affiliation(s)
- Miranda Mele
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Rui O Costa
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Carlos B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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Cho I, Jeong KH, Zhu J, Choi YH, Cho KH, Heo K, Kim WJ. Sirtuin3 Protected Against Neuronal Damage and Cycled into Nucleus in Status Epilepticus Model. Mol Neurobiol 2018; 56:4894-4903. [DOI: 10.1007/s12035-018-1399-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/17/2018] [Indexed: 12/31/2022]
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