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Baset A, Huang F. Shedding light on subiculum's role in human brain disorders. Brain Res Bull 2024; 214:110993. [PMID: 38825254 DOI: 10.1016/j.brainresbull.2024.110993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/17/2024] [Accepted: 05/30/2024] [Indexed: 06/04/2024]
Abstract
Subiculum is a pivotal output component of the hippocampal formation, a structure often overlooked in neuroscientific research. Here, this review aims to explore the role of the subiculum in various brain disorders, shedding light on its significance within the functional-neuroanatomical perspective on neurological diseases. The subiculum's involvement in multiple brain disorders was thoroughly examined. In Alzheimer's disease, subiculum alterations precede cognitive decline, while in epilepsy, the subiculum plays a critical role in seizure initiation. Stress involves the subiculum's impact on the hypothalamic-pituitary-adrenocortical axis. Moreover, the subiculum exhibits structural and functional changes in anxiety, schizophrenia, and Parkinson's disease, contributing to cognitive deficits. Bipolar disorder is linked to subiculum structural abnormalities, while autism spectrum disorder reveals an alteration of inward deformation in the subiculum. Lastly, frontotemporal dementia shows volumetric differences in the subiculum, emphasizing its contribution to the disorder's complexity. Taken together, this review consolidates existing knowledge on the subiculum's role in brain disorders, and may facilitate future research, diagnostic strategies, and therapeutic interventions for various neurological conditions.
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Affiliation(s)
- Abdul Baset
- Department of Neuroscience, City University of Hong Kong, Hong Kong Special Administrative Region of China; Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong Special Administrative Region of China
| | - Fengwen Huang
- Department of Neuroscience, City University of Hong Kong, Hong Kong Special Administrative Region of China; Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong Special Administrative Region of China.
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Chen L, Yang W, Yang F, Xu T, Yu Y, Wu Q, Han Y. Astrocyte mitochondria: Potential therapeutic targets for epilepsy. Heliyon 2024; 10:e29950. [PMID: 38756598 PMCID: PMC11096718 DOI: 10.1016/j.heliyon.2024.e29950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 04/08/2024] [Accepted: 04/17/2024] [Indexed: 05/18/2024] Open
Abstract
Epilepsy is a chronic, relapsing neurological disorder, and current treatments focus primarily on neurons, yet one-third of patients still develop drug-resistant epilepsy. Therefore, there is an urgent need to explore new therapeutic targets. Interestingly, astrocytes can transfer their healthy mitochondria into neighboring neurons, thus preventing neuronal damage. Astrocyte mitochondria have been shown to have a therapeutic role in stroke and neurodegenerative diseases. However, their therapeutic effect in epilepsy and its related mechanisms have been less studied. In this review, we mainly summarize the regulatory role of astrocyte mitochondria in glutamate, calcium ion, and adenosine triphosphate (ATP) homeostasis and outline the protective role of astrocyte mitochondria in nervous system diseases, revealing a new target for epilepsy treatment.
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Affiliation(s)
| | | | - Fei Yang
- First Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Tingwan Xu
- First Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Yanying Yu
- First Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Qian Wu
- First Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Yanbing Han
- First Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
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熊 一, 梁 小, 梁 晓, 李 伟, 钱 益, 谢 炜. [Saikosaponin a alleviates pentylenetetrazol-induced acute epileptic seizures in mouse models of depression by suppressing microglia activation-mediated inflammation]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2024; 44:515-522. [PMID: 38597443 PMCID: PMC11006703 DOI: 10.12122/j.issn.1673-4254.2024.03.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Indexed: 04/11/2024]
Abstract
OBJECTIVE To explore the inhibitory effect of saikosonin a (SSa) on pentylenetetrazol-induced acute epilepsy seizures in a mouse model of depression and explore the mechanism mediating this effect. METHODS Male C57BL/6J mouse models of depression was established by oral administration of corticosterone via drinking water for 3 weeks, and acute epileptic seizures were induced by intraperitoneal injection of a single dose of pentylenetetrazole. The effect of intraperitoneal injection of SSa prior to the treatment on depressive symptoms and epileptic seizures were assessed using behavioral tests, epileptic seizure grading and hippocampal morphology observation. ELISA was used to detect blood corticosterone levels of the mice, and RTqPCR was performed to detect the pro- and anti-inflammatory factors. Microglia activation in the mice was observed using immunofluorescence staining. RESULTS The mouse model of corticosterone-induced depression showed body weight loss and obvious depressive behaviors with significantly increased serum corticosterone level (all P < 0.05). Compared with those with pentylenetetrazole-induced epilepsy alone, the epileptic mice with comorbid depression showed significantly shorter latency of epileptic seizures, increased number, grade and duration of of seizures, reduced Nissl bodies in hippocampal CA1 and CA3 neurons, increased number of Iba1-positive cells, and significantly enhanced hippocampal expressions of IL-1β, IL-10, TNF-α and IFN-γ. Pretreatment of the epileptic mice with SSa significantly prolonged the latency of epileptic seizures, reduced the number, duration, and severity of seizures, increased the number of Nissl bodies, decreased the number of Iba1-positive cells, and reduced the expression levels of IL-1β, IL-10, TNF-α, and IFN-γ in the hippocampus (P < 0.05). CONCLUSION Depressive state aggravates epileptic seizures, increases microglia activation, and elevates inflammation levels. SSA treatment can alleviate acute epileptic seizures in mouse models of depression possibly by suppressing microglia activation-mediated inflammation.
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Affiliation(s)
- 一凡 熊
- 南方医科大学中医药学院,广东 广州 510515School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - 小珊 梁
- 南方医科大学中医药学院,广东 广州 510515School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
- 南方医科大学南方医院中医科,广东 广州 510515Department of Traditional Chinese Medicine, Nanfang Hospital of Southern Medical University, Guangzhou 510515, China
| | - 晓涛 梁
- 南方医科大学中医药学院,广东 广州 510515School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - 伟鹏 李
- 南方医科大学中医药学院,广东 广州 510515School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - 益啸 钱
- 广州市荔湾固生堂中医门诊部,广东 广州 510250Guangzhou Liwan Gushengtang Traditional Chinese Medicine Clinic, Guangzhou 510250, China
| | - 炜 谢
- 南方医科大学中医药学院,广东 广州 510515School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
- 南方医科大学南方医院中医科,广东 广州 510515Department of Traditional Chinese Medicine, Nanfang Hospital of Southern Medical University, Guangzhou 510515, China
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Doyen M, Lambert C, Roeder E, Boutley H, Chen B, Pierson J, Verger A, Raffo E, Karcher G, Marie PY, Maskali F. Assessment of a one-week ketogenic diet on brain glycolytic metabolism and on the status epilepticus stage of a lithium-pilocarpine rat model. Sci Rep 2024; 14:5063. [PMID: 38424459 PMCID: PMC10904769 DOI: 10.1038/s41598-024-53824-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 02/05/2024] [Indexed: 03/02/2024] Open
Abstract
The ketogenic diet (KD) has been shown to be effective in refractory epilepsy after long-term administration. However, its interference with short-term brain metabolism and its involvement in the early process leading to epilepsy remain poorly understood. This study aimed to assess the effect of a short-term ketogenic diet on cerebral glucose metabolic changes, before and after status epilepticus (SE) in rats, by using [18F]-FDG PET. Thirty-nine rats were subjected to a one-week KD (KD-rats, n = 24) or to a standard diet (SD-rats, n = 15) before the induction of a status epilepticus (SE) by lithium-pilocarpine administrations. Brain [18F]-FDG PET scans were performed before and 4 h after this induction. Morphological MRIs were acquired and used to spatially normalize the PET images which were then analyzed voxel-wisely using a statistical parametric-based method. Twenty-six rats were analyzed (KD-rats, n = 15; SD-rats, n = 11). The 7 days of the KD were associated with significant increases in the plasma β-hydroxybutyrate level, but with an unchanged glycemia. The PET images, recorded after the KD and before SE induction, showed an increased metabolism within sites involved in the appetitive behaviors: hypothalamic areas and periaqueductal gray, whereas no area of decreased metabolism was observed. At the 4th hour following the SE induction, large metabolism increases were observed in the KD- and SD-rats in areas known to be involved in the epileptogenesis process late-i.e., the hippocampus, parahippocampic, thalamic and hypothalamic areas, the periaqueductal gray, and the limbic structures (and in the motor cortex for the KD-rats only). However, no statistically significant difference was observed when comparing SD and KD groups at the 4th hour following the SE induction. A one-week ketogenic diet does not prevent the status epilepticus (SE) and associated metabolic brain abnormalities in the lithium-pilocarpine rat model. Further explorations are needed to determine whether a significant prevention could be achieved by more prolonged ketogenic diets and by testing this diet in less severe experimental models, and moreover, to analyze the diet effects on the later and chronic stages leading to epileptogenesis.
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Affiliation(s)
- Matthieu Doyen
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France.
- Lorraine University, IADI, INSERM UMR 1254, 54000, Nancy, France.
| | - Clémentine Lambert
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France
- Department of Neuropediatrics, Children's Hospital CHRU Nancy, 54000, Nancy, France
| | - Emilie Roeder
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France
| | - Henri Boutley
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France
| | - Bailiang Chen
- CHRU-Nancy, INSERM UMR 1433, CIC, Innovation Technologique, Université de Lorraine, 54000, Nancy, France
| | - Julien Pierson
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France
| | - Antoine Verger
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France
- Lorraine University, IADI, INSERM UMR 1254, 54000, Nancy, France
- Department of Nuclear Medicine, University Hospital, 54000, Nancy, France
| | - Emmanuel Raffo
- Department of Neuropediatrics, Children's Hospital CHRU Nancy, 54000, Nancy, France
| | - Gilles Karcher
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France
- Department of Nuclear Medicine, University Hospital, 54000, Nancy, France
| | - Pierre-Yves Marie
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France
- Lorraine University, IADI, INSERM UMR 1254, 54000, Nancy, France
- Department of Nuclear Medicine, University Hospital, 54000, Nancy, France
| | - Fatiha Maskali
- NANCYCLOTEP-Molecular and Experimental Imaging Platform, 54000, Nancy, France
- Lorraine University, INSERM DCAC1116, 54000, Nancy, France
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Sint Jago SC, Bahabry R, Schreiber AM, Homola J, Ngyuen T, Meijia F, Allendorfer JB, Lubin FD. Aerobic exercise alters DNA hydroxymethylation levels in an experimental rodent model of temporal lobe epilepsy. Epilepsy Behav Rep 2023; 25:100642. [PMID: 38323091 PMCID: PMC10844942 DOI: 10.1016/j.ebr.2023.100642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/24/2023] [Accepted: 12/26/2023] [Indexed: 02/08/2024] Open
Abstract
The therapeutic potential of aerobic exercise in mitigating seizures and cognitive issues in temporal lobe epilepsy (TLE) is recognized, yet the underlying mechanisms are not well understood. Using a rodent TLE model induced by Kainic acid (KA), we investigated the impact of a single bout of exercise (i.e., acute) or 4 weeks of aerobic exercise (i.e., chronic). Blood was processed for epilepsy-associated serum markers, and DNA methylation (DNAme), and hippocampal area CA3 was assessed for gene expression levels for DNAme-associated enzymes. While acute aerobic exercise did not alter serum Brain-Derived Neurotrophic Factor (BDNF) or Interleukin-6 (IL-6), chronic exercise resulted in an exercise-specific decrease in serum BDNF and an increase in serum IL-6 levels in epileptic rats. Additionally, whole blood DNAme levels, specifically 5-hydroxymethylcytosine (5-hmC), decreased in epileptic animals following chronic exercise. Hippocampal CA3 5-hmC levels and ten-eleven translocation protein (TET1) expression mirrored these changes. Furthermore, immunohistochemistry analysis revealed that most 5-hmC changes in response to chronic exercise were neuron-specific within area CA3 of the hippocampus. Together, these findings suggest that DNAme mechanisms in the rodent model of TLE are responsive to chronic aerobic exercise, with emphasis on neuronal 5-hmC DNAme in the epileptic hippocampus.
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Affiliation(s)
| | - Rudhab Bahabry
- Department of Neurobiology, University of Alabama at Birmingham, United States
| | | | - Julia Homola
- Department of Neurobiology, University of Alabama at Birmingham, United States
| | - Tram Ngyuen
- Department of Neurobiology, University of Alabama at Birmingham, United States
| | - Fernando Meijia
- Department of Neurobiology, University of Alabama at Birmingham, United States
| | - Jane B. Allendorfer
- Department of Neurobiology, University of Alabama at Birmingham, United States
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Farah D. Lubin
- Department of Neurobiology, University of Alabama at Birmingham, United States
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Liang XS, Qian TL, Xiong YF, Liang XT, Ding YW, Zhu XY, Li YL, Zhou JL, Tan LY, Li WP, Xie W. IRAK-M Ablation Promotes Status Epilepticus-Induced Neuroinflammation via Activating M1 Microglia and Impairing Excitatory Synaptic Function. Mol Neurobiol 2023; 60:5199-5213. [PMID: 37277682 DOI: 10.1007/s12035-023-03407-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 05/25/2023] [Indexed: 06/07/2023]
Abstract
Epilepsy is one of the most common neurological disorders. The pro-epileptic and antiepileptic roles of microglia have recently garnered significant attention. Interleukin-1 receptor-associated kinase (IRAK)-M, an important kinase in the innate immune response, is mainly expressed in microglia and acts as a negative regulator of the TLR4 signaling pathway that mediates the anti-inflammatory effect. However, whether IRAK-M exerts a protective role in epileptogenesis as well as the molecular and cellular mechanisms underlying these processes are yet to be elucidated. An epilepsy mouse model induced by pilocarpine was used in this study. Real-time quantitative polymerase chain reaction and western blot analysis were used to analyze mRNA and protein expression levels, respectively. Whole-cell voltage-clamp recordings were employed to evaluate the glutamatergic synaptic transmission in hippocampal neurons. Immunofluorescence was utilized to show the glial cell activation and neuronal loss. Furthermore, the proportion of microglia was analyzed using flow cytometry. Seizure dynamics influenced the expression of IRAK-M. Its knockout dramatically exacerbated the seizures and the pathology in epilepsy and increased the N-methyl-d-aspartate receptor (NMDAR) expression, thereby enhancing glutamatergic synaptic transmission in hippocampal CA1 pyramidal neurons in mice. Furthermore, IRAK-M deficiency augmented hippocampal neuronal loss via a possible mechanism of NMDAR-mediated excitotoxicity. IRAK-M deletion promotes microglia toward the M1 phenotype, which resulted in high levels of proinflammatory cytokines and was accompanied by a visible increase in the expressions of key microglial polarization-related proteins, including p-STAT1, TRAF6, and SOCS1. The findings demonstrate that IRAK-M dysfunction contributes to the progression of epilepsy by increasing M1 microglial polarization and glutamatergic synaptic transmission. This is possibly related to NMDARs, particularly Grin2A and Grin2B, which suggests that IRAK-M could serve as a novel therapeutic target for the direct alleviation of epilepsy.
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Affiliation(s)
- Xiao-Shan Liang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Ting-Lin Qian
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Yi-Fan Xiong
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Xiao-Tao Liang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Yue-Wen Ding
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
- Department of Traditional Chinese Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Xiao-Yu Zhu
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Yun-Lv Li
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Jie-Li Zhou
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Le-Yi Tan
- The First School of Clinical Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Wei-Peng Li
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China.
- Department of Neurology, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China.
| | - Wei Xie
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China.
- Department of Traditional Chinese Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
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Liu Z, Huang W, Zhu M, Xu Z, Xu Z, Yu C, Huang H. Mechanism of Robo1 in the pentylenetetrazol-kindled epilepsy mouse model. IBRAIN 2023; 9:369-380. [PMID: 38680506 PMCID: PMC11045194 DOI: 10.1002/ibra.12127] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 08/02/2023] [Accepted: 08/04/2023] [Indexed: 04/28/2024]
Abstract
The neural network hypothesis is one of the important pathogenesis of drug-resistant epilepsy. Axons guide molecules through synaptic remodeling and brain tissue remodeling, which may result in the formation of abnormal neural networks. Therefore, axon guidance plays a crucial role in disease progression. However, although Robo1 is one of the important components of axon guidance, the role of Robo1 in epilepsy remains unclear. In this study, we aimed to explore the mechanism of Robo1 in epilepsy. Male adult C57BL/6 mice were intraperitoneally injected with pentylenetetrazol to establish an epilepsy model. Lentivirus (LV) was given via intracranial injection 2 weeks before pentylenetetrazol injection. Different expressions of Robo1 between the control group, LV-mediated Robo1 short hairpin RNA group, empty vector control LV group, and normal saline group were analyzed using Western blot, immunofluorescence staining, Golgi staining, and video monitoring. Robo1 was increased in the hippocampus in the pentylenetetrazol-induced epilepsy mouse model; lentiviral Robo1 knockdown prolonged the latency of seizure and reduced the seizure grade in mice and resulted in a decrease in dendritic spine density, while the number of mature dendritic spines was maintained. We speculate that Robo1 has been implicated in the development and progression of epilepsy through its effects on dendritic spine morphology and density. Epileptic mice with Robo1 knockdown virus intervention had lower seizure grade and longer latency. Follow-up findings suggest that Robo1 may modulate seizures by affecting dendritic spine density and morphology. Downregulation of Robo1 may negatively regulate epileptogenesis by decreasing the density of dendritic spines and maintaining a greater number of mature dendritic spines.
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Affiliation(s)
- Zheng Liu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Wei Huang
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Man‐Min Zhu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Zhong‐Xiang Xu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Zu‐Cai Xu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Chang‐Yin Yu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Hao Huang
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
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Beesley S, Kumar SS. The t-N-methyl-d-aspartate receptor: Making the case for d-Serine to be considered its inverse co-agonist. Neuropharmacology 2023:109654. [PMID: 37437688 DOI: 10.1016/j.neuropharm.2023.109654] [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: 04/27/2023] [Revised: 06/22/2023] [Accepted: 07/06/2023] [Indexed: 07/14/2023]
Abstract
The N-methyl-d-aspartate receptor (NMDAR) is an enigmatic macromolecule that has garnered a good deal of attention on account of its involvement in the cellular processes that underlie learning and memory, following its discovery in the mid twentieth century (Baudry and Davis, 1991). Yet, despite advances in knowledge about its function, there remains much more to be uncovered regarding the receptor's biophysical properties, subunit composition, and role in CNS physiology and pathophysiology. The motivation for this review stems from the need for synthesizing new information gathered about these receptors that sheds light on their role in synaptic plasticity and their dichotomous relationship with the amino acid d-serine through which they influence the pathogenesis of neurodegenerative diseases like temporal lobe epilepsy (TLE), the most common type of adult epilepsies (Beesley et al., 2020a). This review will outline pertinent ideas relating structure and function of t-NMDARs (GluN3 subunit-containing triheteromeric NMDARs) for which d-serine might serve as an inverse co-agonist. We will explore how tracing d-serine's origins blends glutamate-receptor biology with glial biology to help provide fresh perspectives on how neurodegeneration might interlink with neuroinflammation to initiate and perpetuate the disease state. Taken together, we envisage the review to deepen our understanding of endogenous d-serine's new role in the brain while also recognizing its therapeutic potential in the treatment of TLE that is oftentimes refractory to medications.
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Affiliation(s)
- Stephen Beesley
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience Florida State University, 1115 W. Call Street, Tallahassee, FL, 32306-4300, USA
| | - Sanjay S Kumar
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience Florida State University, 1115 W. Call Street, Tallahassee, FL, 32306-4300, USA.
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Curia G. Hebbian and homeostatic synaptic plasticity of AMPA receptors in epileptogenesis. Cell Rep Med 2023; 4:101047. [PMID: 37196628 DOI: 10.1016/j.xcrm.2023.101047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 04/19/2023] [Accepted: 04/20/2023] [Indexed: 05/19/2023]
Abstract
AMPA receptors' synaptic plasticity is involved in epileptogenesis. In this issue, Eiro et al.1 demonstrate that Hebbian plasticity is responsible for increased AMPAR in focal seizures, while homeostatic plasticity induces the reduction of AMPAR in generalized onset seizures.
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Affiliation(s)
- Giulia Curia
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy.
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Gu J, Ke P, Guo H, Liu J, Liu Y, Tian X, Huang Z, Xu X, Xu D, Ma Y, Wang X, Xiao F. KCTD13-mediated ubiquitination and degradation of GluN1 regulates excitatory synaptic transmission and seizure susceptibility. Cell Death Differ 2023:10.1038/s41418-023-01174-5. [PMID: 37142655 DOI: 10.1038/s41418-023-01174-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 04/18/2023] [Accepted: 04/25/2023] [Indexed: 05/06/2023] Open
Abstract
Temporal lobe epilepsy (TLE) is the most common and severe form of epilepsy in adults; however, its underlying pathomechanisms remain elusive. Dysregulation of ubiquitination is increasingly recognized to contribute to the development and maintenance of epilepsy. Herein, we observed for the first time that potassium channel tetramerization domain containing 13 (KCTD13) protein, a substrate-specific adapter for cullin3-based E3 ubiquitin ligase, was markedly down-regulated in the brain tissue of patients with TLE. In a TLE mouse model, the protein expression of KCTD13 dynamically changed during epileptogenesis. Knockdown of KCTD13 in the mouse hippocampus significantly enhanced seizure susceptibility and severity, whereas overexpression of KCTD13 showed the opposite effect. Mechanistically, GluN1, an obligatory subunit of N-methyl-D-aspartic acid receptors (NMDARs), was identified as a potential substrate protein of KCTD13. Further investigation revealed that KCTD13 facilitates lysine-48-linked polyubiquitination of GluN1 and its degradation through the ubiquitin-proteasome pathway. Besides, the lysine residue 860 of GluN1 is the main ubiquitin site. Importantly, dysregulation of KCTD13 affected membrane expression of glutamate receptors and impaired glutamate synaptic transmission. Systemic administration of the NMDAR inhibitor memantine significantly rescued the epileptic phenotype aggravated by KCTD13 knockdown. In conclusion, our results demonstrated an unrecognized pathway of KCTD13-GluN1 in epilepsy, suggesting KCTD13 as a potential neuroprotective therapeutic target for epilepsy.
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Affiliation(s)
- Juan Gu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
- Department of Neurology, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou, 646000, China
| | - Pingyang Ke
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Haokun Guo
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Jing Liu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Yan Liu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Xin Tian
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Zhuo Huang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, 100191, Beijing, China
| | - Xin Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Demei Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Yuanlin Ma
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Xuefeng Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China.
| | - Fei Xiao
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China.
- Institute for Brain Science and Disease of Chongqing Medical University, Chongqing, 400016, China.
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11
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Tavassoli Z, Giahi M, Janahmadi M, Hosseinmardi N. Glial cells inhibition affects the incidence of metaplasticity in the hippocampus of Pentylentetrazole-induced kindled rats. Epilepsy Behav 2022; 135:108907. [PMID: 36095872 DOI: 10.1016/j.yebeh.2022.108907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 08/21/2022] [Accepted: 08/27/2022] [Indexed: 11/18/2022]
Abstract
Epilepsy is characterized by the unpredictability but recurrence of seizures caused by the synchronized aberrant firing of neuronal populations. It has been shown that astrocytes (one of the most prominent glial cells) are ideally positioned to induce or contribute to neural network synchronization. Although astrocytes cannot generate action potentials, they have the capacity to sense and respond to neuronal activity, which allows them to function as homeostatic regulators of synaptic interactions. Considering the necessity of astrocyte-neuron bidirectional interactions in synaptic transmission and plasticity, in the current study, the role of astrocytes in synaptic metaplasticity and resultant behavioral seizures induced by Pentylentetrazole (PTZ) was assessed. Rats were kindled by intraperitoneal (i.p.) injection of PTZ (30 mg/kg/48 h). A glial cell inhibitor, Fluorocitrate (FC), was injected into the right lateral cerebral ventricle of the rat 30 min before PTZ during kindling progress. The maximal seizure stage (SS), stage 2 and 4 latency (S2L, S4L), stage 4 and 5 duration (S4D, S5D), and seizure duration (SD) were all assessed 20 min after PTZ administration by observation. Following Schaffer collateral stimulation, in vivo field, potential recordings from the CA1 area of the hippocampus were employed to assess the metaplasticity induced in kindled rats. The inhibition of glial cells during the kindling process significantly lowered SS, S4D&S5D and increased S4L (Two-way ANOVA, Bonferroni Posttest, P < 0.05, P < 0.01, and P < 0.001). In comparison to the control group, electrophysiological data demonstrated that HFS-induced LTP in kindled animals was decreased (Unpaired t-test, P < 0.05). Glial cell inhibition prevented PTZ's effect on LTP. Our data imply that kindling altered CA1 pyramidal neurons' vulnerability to synaptic plasticity. This shift in neuronal plasticity (metaplasticity) is mediated in part by glial cells and is important in the formation of seizure symptoms. As a result, glial cell inhibition was found to alleviate seizure behavior.
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Affiliation(s)
- Zohreh Tavassoli
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohadeseh Giahi
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahyar Janahmadi
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Narges Hosseinmardi
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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12
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Kim S, Park S, Choi TG, Kim SS. Role of Short Chain Fatty Acids in Epilepsy and Potential Benefits of Probiotics and Prebiotics: Targeting “Health” of Epileptic Patients. Nutrients 2022; 14:nu14142982. [PMID: 35889939 PMCID: PMC9322917 DOI: 10.3390/nu14142982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/17/2022] [Accepted: 07/19/2022] [Indexed: 11/16/2022] Open
Abstract
The WHO’s definition of health transcends the mere absence of disease, emphasizing physical, mental, and social well-being. As this perspective is being increasingly applied to the management of chronic diseases, research on gut microbiota (GM) is surging, with a focus on its potential for persistent and noninvasive dietary therapeutics. In patients with epilepsy (PWE), a chronic lack of seizure control along with often neglected psychiatric comorbidities greatly disrupt the quality of life. Evidence shows that GM-derived short chain fatty acids (SCFAs) may impact seizure susceptibility through modulating (1) excitatory/inhibitory neurotransmitters, (2) oxidative stress and neuroinflammation, and (3) psychosocial stress. These functions are also connected to shared pathologies of epilepsy and its two most common psychiatric consequences: depression and anxiety. As the enhancement of SCFA production is enabled through direct administration, as well as probiotics and prebiotics, related dietary treatments may exert antiseizure effects. This paper explores the potential roles of SCFAs in the context of seizure control and its mental comorbidities, while analyzing existing studies on the effects of pro/prebiotics on epilepsy. Based on currently available data, this study aims to interpret the role of SCFAs in epileptic treatment, extending beyond the absence of seizures to target the health of PWE.
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Affiliation(s)
- Soomin Kim
- Department of Preliminary Medicine, School of Medicine, Kyung Hee University, Seoul 02447, Korea;
| | - Siyeon Park
- School of Pharmacy, Massachusetts College of Pharmacy and Health Sciences, Boston, MA 02115, USA;
| | - Tae Gyu Choi
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Korea
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Korea
- Correspondence: (T.G.C.); (S.S.K.); Tel.: +82-2-961-0287 (T.G.C.); +82-2-961-0524 (S.S.K.)
| | - Sung Soo Kim
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Korea
- Biomedical Science Institute, Kyung Hee University, Seoul 02447, Korea
- Correspondence: (T.G.C.); (S.S.K.); Tel.: +82-2-961-0287 (T.G.C.); +82-2-961-0524 (S.S.K.)
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13
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Liu Y, Tian X, Ke P, Gu J, Ma Y, Guo Y, Xu X, Chen Y, Yang M, Wang X, Xiao F. KIF17 Modulates Epileptic Seizures and Membrane Expression of the NMDA Receptor Subunit NR2B. Neurosci Bull 2022; 38:841-856. [PMID: 35678994 PMCID: PMC9352834 DOI: 10.1007/s12264-022-00888-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Accepted: 04/01/2022] [Indexed: 10/18/2022] Open
Abstract
Epilepsy is a common and severe brain disease affecting >65 million people worldwide. Recent studies have shown that kinesin superfamily motor protein 17 (KIF17) is expressed in neurons and is involved in regulating the dendrite-targeted transport of N-methyl-D-aspartate receptor subtype 2B (NR2B). However, the effect of KIF17 on epileptic seizures remains to be explored. We found that KIF17 was mainly expressed in neurons and that its expression was increased in epileptic brain tissue. In the kainic acid (KA)-induced epilepsy mouse model, KIF17 overexpression increased the severity of epileptic activity, whereas KIF17 knockdown had the opposite effect. In electrophysiological tests, KIF17 regulated excitatory synaptic transmission, potentially due to KIF17-mediated NR2B membrane expression. In addition, this report provides the first demonstration that KIF17 is modified by SUMOylation (SUMO, small ubiquitin-like modifier), which plays a vital role in the stabilization and maintenance of KIF17 in epilepsy.
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Affiliation(s)
- Yan Liu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Xin Tian
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Pingyang Ke
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Juan Gu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Yuanlin Ma
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Yi Guo
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Xin Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Yuanyuan Chen
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Min Yang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China
| | - Xuefeng Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China.
| | - Fei Xiao
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, 400016, China.
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14
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Cao Y, Sun C, Huang J, Sun P, Wang L, He S, Liao J, Lu Z, Lu Y, Zhong C. Dysfunction of the Hippocampal-Lateral Septal Circuit Impairs Risk Assessment in Epileptic Mice. Front Mol Neurosci 2022; 15:828891. [PMID: 35571372 PMCID: PMC9103201 DOI: 10.3389/fnmol.2022.828891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 03/29/2022] [Indexed: 11/16/2022] Open
Abstract
Temporal lobe epilepsy, a chronic disease of the brain characterized by degeneration of the hippocampus, has impaired risk assessment. Risk assessment is vital for survival in complex environments with potential threats. However, the underlying mechanisms remain largely unknown. The intricate balance of gene regulation and expression across different brain regions is related to the structure and function of specific neuron subtypes. In particular, excitation/inhibition imbalance caused by hyperexcitability of glutamatergic neurons and/or dysfunction of GABAergic neurons, have been implicated in epilepsy. First, we estimated the risk assessment (RA) by evaluating the behavior of mice in the center of the elevated plus maze, and found that the kainic acid-induced temporal lobe epilepsy mice were specifically impaired their RA. This experiment evaluated approach-RA, with a forthcoming approach to the open arm, and avoid-RA, with forthcoming avoidance of the open arm. Next, results from free-moving electrophysiological recordings showed that in the hippocampus, ∼7% of putative glutamatergic neurons and ∼15% of putative GABAergic neurons were preferentially responsive to either approach-risk assessment or avoid-risk assessment, respectively. In addition, ∼12% and ∼8% of dorsal lateral septum GABAergic neurons were preferentially responsive to approach-risk assessment and avoid-risk assessment, respectively. Notably, during the impaired approach-risk assessment, the favorably activated dorsal dentate gyrus and CA3 glutamatergic neurons increased (∼9%) and dorsal dentate gyrus and CA3 GABAergic neurons decreased (∼7%) in the temporal lobe epilepsy mice. Then, we used RNA sequencing and immunohistochemical staining to investigate which subtype of GABAergic neuron loss may contribute to excitation/inhibition imbalance. The results show that temporal lobe epilepsy mice exhibit significant neuronal loss and reorganization of neural networks. In particular, the dorsal dentate gyrus and CA3 somatostatin-positive neurons and dorsal lateral septum cholecystokinin-positive neurons are selectively vulnerable to damage after temporal lobe epilepsy. Optogenetic activation of the hippocampal glutamatergic neurons or chemogenetic inhibition of the hippocampal somatostatin neurons directly disrupts RA, suggesting that an excitation/inhibition imbalance in the dHPC dorsal lateral septum circuit results in the impairment of RA behavior. Taken together, this study provides insight into epilepsy and its comorbidity at different levels, including molecular, cell, neural circuit, and behavior, which are expected to decrease injury and premature mortality in patients with epilepsy.
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Affiliation(s)
- Yi Cao
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
- Division of Life Sciences and Medicine, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Chongyang Sun
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
| | - Jianyu Huang
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
- Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Peng Sun
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
- College of Electronic and Information Engineering, Hebei University, Baoding, China
| | - Lulu Wang
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
| | - Shuyu He
- Shenzhen Children’s Hospital, China Medical University, Shenzhen, China
| | - Jianxiang Liao
- Epilepsy Center, Shenzhen Children’s Hospital, Shenzhen, China
| | - Zhonghua Lu
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
| | - Yi Lu
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
- Yi Lu,
| | - Cheng Zhong
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
- *Correspondence: Cheng Zhong,
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15
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Wu Q, Wang H, Liu X, Zhao Y, Zhang J. The Role of the Negative Regulation of Microglia-Mediated Neuroinflammation in Improving Emotional Behavior After Epileptic Seizures. Front Neurol 2022; 13:823908. [PMID: 35493845 PMCID: PMC9046666 DOI: 10.3389/fneur.2022.823908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 03/16/2022] [Indexed: 11/13/2022] Open
Abstract
ObjectiveStudies have long shown that uncontrolled inflammatory responses in the brain play a key role in epilepsy pathogenesis. Microglias play an important role in epileptic-induced neuroinflammation, but their role after epileptic seizures is still poorly understood. Alleviating epilepsy and its comorbidities has become a key area of interest for pediatricians.MethodsA pilocarpine-induced rat model of epilepsy was established. The rats were randomly divided into four groups: a control group, epilepsy group, TLR4 inhibitor group (epilepsy+TAK-242), and NF-κB antagonist group (epilepsy+BAY11–7082).Results1. The results of TUNEL staining showed that the expression in rats in the epilepsy group was the most obvious and was significantly different from that in rats in the control, EP+BAY and EP+TAK groups. 2. The expression of TLR4 and NF-κB was highest in rats in the epilepsy group and was significantly different from that in rats in the control, EP+BAY and EP+TAK groups. 3. The fluorescence intensity and number of IBA-1-positive cells in rats in the epilepsy group were highest and significantly different from those in rats in the control, EP+BAY and EP+TAK groups. Western blot analysis of IBA-1 showed that the expression in rats in the epilepsy group was the highest and was statistically significant. 4. CD68 was the highest in rats in the epilepsy group and was statistically significant. 5. In the open-field experiment, the central region residence time of rats in the EP group was delayed, the central region movement distance traveled was prolonged, the total distance traveled was prolonged, and the average speed was increased. Compared with rats in the EP group, rats in the EP+BAY and EP+ TAK groups exhibited improvements to different degrees.ConclusionAt the tissue level, downregulation of the TLR4/NF-κB inflammatory pathway in epilepsy could inhibit microglial activation and the expression of the inflammatory factor CD68, could inhibit hyperphagocytosis, and inhibit the occurrence and exacerbation of epilepsy, thus improving cognitive and emotional disorders after epileptic seizures.
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Mokhothu TM, Tanaka KZ. Characterizing Hippocampal Oscillatory Signatures Underlying Seizures in Temporal Lobe Epilepsy. Front Behav Neurosci 2021; 15:785328. [PMID: 34899205 PMCID: PMC8656355 DOI: 10.3389/fnbeh.2021.785328] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 10/29/2021] [Indexed: 01/01/2023] Open
Abstract
Temporal Lobe Epilepsy (TLE) is a neurological condition characterized by focal brain hyperexcitability, resulting in abnormal neuronal discharge and uncontrollable seizures. The hippocampus, with its inherently highly synchronized firing patterns and relatively high excitability, is prone to epileptic seizures, and it is usually the focus of TLE. Researchers have identified hippocampal high-frequency oscillations (HFOs) as a salient feature in people with TLE and animal models of this disease, arising before or at the onset of the epileptic event. To a certain extent, these pathological HFOs have served as a marker and a potential target for seizure attenuation using electrical or optogenetic interventions. However, many questions remain about whether we can reliably distinguish pathological from non-pathological HFOs and whether they can tell us about the development of the disease. While this would be an arduous task to perform in humans, animal models of TLE provide an excellent opportunity to study the characteristics of HFOs in predicting how epilepsy evolves. This minireview will (1) summarize what we know about the oscillatory disruption in TLE, (2) summarize knowledge about oscillatory changes in the latent period and their role in predicting seizures, and (3) propose future studies essential to uncovering potential treatments based on early detection of pathological HFOs.
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Affiliation(s)
- Thato Mary Mokhothu
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Kazumasa Zen Tanaka
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
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