1
|
Lu T, Chen X, Zhang Q, Shang K, Yang X, Xiang W. Vitamin D Relieves Epilepsy Symptoms and Neuroinflammation in Juvenile Mice by Activating the mTOR Signaling Pathway via RAF1: Insights from Network Pharmacology and Molecular Docking Studies. Neurochem Res 2024:10.1007/s11064-024-04176-y. [PMID: 38837094 DOI: 10.1007/s11064-024-04176-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 03/15/2024] [Accepted: 05/22/2024] [Indexed: 06/06/2024]
Abstract
Epilepsy is a common neurological disorder, and the exploration of potential therapeutic drugs for its treatment is still ongoing. Vitamin D has emerged as a promising treatment due to its potential neuroprotective effects and anti-epileptic properties. This study aimed to investigate the effects of vitamin D on epilepsy and neuroinflammation in juvenile mice using network pharmacology and molecular docking, with a focus on the mammalian target of rapamycin (mTOR) signaling pathway. Experimental mouse models of epilepsy were established through intraperitoneal injection of pilocarpine, and in vitro injury models of hippocampal neurons were induced by glutamate (Glu) stimulation. The anti-epileptic effects of vitamin D were evaluated both in vivo and in vitro. Network pharmacology and molecular docking analysis were used to identify potential targets and regulatory pathways of vitamin D in epilepsy. The involvement of the mTOR signaling pathway in the regulation of mouse epilepsy by vitamin D was validated using rapamycin (RAPA). The levels of inflammatory cytokines (TNF-α, IL-1β, and IL-6) were assessed by enzyme-linked immunosorbent assay (ELISA). Gene and protein expressions were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) staining was used to analyze the apoptosis of hippocampal neurons. In in vivo experiments, vitamin D reduced the Racine scores of epileptic mice, prolonged the latency of epilepsy, and inhibited the production of TNF-α, IL-1β, and IL-6 in the hippocampus. Furthermore, network pharmacology analysis identified RAF1 as a potential target of vitamin D in epilepsy, which was further confirmed by molecular docking analysis. Additionally, the mTOR signaling pathway was found to be involved in the regulation of mouse epilepsy by vitamin D. In in vitro experiments, Glu stimulation upregulated the expressions of RAF1 and LC3II/LC3I, inhibited mTOR phosphorylation, and induced neuronal apoptosis. Mechanistically, vitamin D activated the mTOR signaling pathway and alleviated mouse epilepsy via RAF1, while the use of the pathway inhibitor RAPA reversed this effect. Vitamin D alleviated epilepsy symptoms and neuroinflammation in juvenile mice by activating the mTOR signaling pathway via RAF1. These findings provided new insights into the molecular mechanisms underlying the anti-epileptic effects of vitamin D and further supported its use as an adjunctive therapy for existing anti-epileptic drugs.
Collapse
Affiliation(s)
- Tiantian Lu
- School of Pediatrics, Hainan Medical University, Haikou, 571199, China
- Department of Neonatology, Haikou Maternal and Child Health Hospital, Haikou, 570203, China
| | - Xiuling Chen
- Department of Pediatric Medicine, Affiliated Haikou Hospital of Xiangya Medical School Central South University, Haikou, 570208, China
| | - Qin Zhang
- Department of Neurosurgery, Hainan Women and Children's Medical Center, Haikou, 570312, China
| | - Kun Shang
- Institute of Deep-sea Science and Engineering, Chinese Academy of Science, Sanya, 572000, China
| | - Xiaogui Yang
- Department of Neonatology, Haikou Maternal and Child Health Hospital, Haikou, 570203, China
| | - Wei Xiang
- School of Pediatrics, Hainan Medical University, Haikou, 571199, China.
- Hainan Women and Children's Medical Center, Hainan Medical University, Haikou, 570312, China.
- National Health Commission (NHC) Key Laboratory of Tropical Disease Control, Hainan Medical University, Haikou, 570216, China.
| |
Collapse
|
2
|
Zeng C, Lu Y, Wei X, Sun L, Wei L, Ou S, Huang Q, Wu Y. Parvalbumin Regulates GAD Expression through Calcium Ion Concentration to Affect the Balance of Glu-GABA and Improve KA-Induced Status Epilepticus in PV-Cre Transgenic Mice. ACS Chem Neurosci 2024; 15:1951-1966. [PMID: 38696478 DOI: 10.1021/acschemneuro.3c00600] [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] [Indexed: 05/04/2024] Open
Abstract
Aims: the study aimed to (i) use adeno-associated virus technology to modulate parvalbumin (PV) gene expression, both through overexpression and silencing, within the hippocampus of male mice and (ii) assess the impact of PV on the metabolic pathway of glutamate and γ-aminobutyric acid (GABA). Methods: a status epilepticus (SE) mouse model was established by injecting kainic acid into the hippocampus of transgenic mice. When the seizures of mice reached SE, the mice were killed at that time point and 30 min after the onset of SE. Hippocampal tissues were extracted and the mRNA and protein levels of PV and the 65 kDa (GAD65) and 67 kDa (GAD67) isoforms of glutamate decarboxylase were assessed using real-time quantitative polymerase chain reaction and Western blot, respectively. The concentrations of glutamate and GABA were detected with high-performance liquid chromatography (HPLC), and the intracellular calcium concentration was detected using flow cytometry. Results: we demonstrate that the expression of PV is associated with GAD65 and GAD67 and that PV regulates the levels of GAD65 and GAD67. PV was correlated with calcium concentration and GAD expression. Interestingly, PV overexpression resulted in a reduction in calcium ion concentration, upregulation of GAD65 and GAD67, elevation of GABA concentration, reduction in glutamate concentration, and an extension of seizure latency. Conversely, PV silencing induced the opposite effects. Conclusion: parvalbumin may affect the expression of GAD65 and GAD67 by regulating calcium ion concentration, thereby affecting the metabolic pathways associated with glutamate and GABA. In turn, this contributes to the regulation of seizure activity.
Collapse
Affiliation(s)
- Chunmei Zeng
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, #6 Shuangyong Road,Nanning, Guangxi 530021, China
| | - Yuling Lu
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, #6 Shuangyong Road,Nanning, Guangxi 530021, China
| | - Xing Wei
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, #6 Shuangyong Road,Nanning, Guangxi 530021, China
| | - Lanfeng Sun
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, #6 Shuangyong Road,Nanning, Guangxi 530021, China
| | - Lei Wei
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, #6 Shuangyong Road,Nanning, Guangxi 530021, China
| | - Sijie Ou
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, #6 Shuangyong Road,Nanning, Guangxi 530021, China
| | - Qi Huang
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, #6 Shuangyong Road,Nanning, Guangxi 530021, China
| | - Yuan Wu
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, #6 Shuangyong Road,Nanning, Guangxi 530021, China
| |
Collapse
|
3
|
Dhamne SC, Modi ME, Gray A, Bonazzi S, Craig L, Bainbridge E, Lalani L, Super CE, Schaeffer S, Capre K, Lubicka D, Liang G, Burdette D, McTighe SM, Gurnani S, Vermudez SAD, Curtis D, Wilson CJ, Hameed MQ, D'Amore A, Rotenberg A, Sahin M. Seizure reduction in TSC2-mutant mouse model by an mTOR catalytic inhibitor. Ann Clin Transl Neurol 2023; 10:1790-1801. [PMID: 37545094 PMCID: PMC10578885 DOI: 10.1002/acn3.51868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 07/14/2023] [Accepted: 07/23/2023] [Indexed: 08/08/2023] Open
Abstract
OBJECTIVE Tuberous sclerosis complex (TSC) is a neurodevelopmental disorder caused by autosomal-dominant pathogenic variants in either the TSC1 or TSC2 gene, and it is characterized by hamartomas in multiple organs, such as skin, kidney, lung, and brain. These changes can result in epilepsy, learning disabilities, and behavioral complications, among others. The mechanistic link between TSC and the mechanistic target of the rapamycin (mTOR) pathway is well established, thus mTOR inhibitors can potentially be used to treat the clinical manifestations of the disorder, including epilepsy. METHODS In this study, we tested the efficacy of a novel mTOR catalytic inhibitor (here named Tool Compound 1 or TC1) previously reported to be more brain-penetrant compared with other mTOR inhibitors. Using a well-characterized hypomorphic Tsc2 mouse model, which displays a translationally relevant seizure phenotype, we tested the efficacy of TC1. RESULTS Our results show that chronic treatment with this novel mTOR catalytic inhibitor (TC1), which affects both the mTORC1 and mTORC2 signaling complexes, reduces seizure burden, and extends the survival of Tsc2 hypomorphic mice, restoring species typical weight gain over development. INTERPRETATION Novel mTOR catalytic inhibitor TC1 exhibits a promising therapeutic option in the treatment of TSC.
Collapse
Affiliation(s)
- Sameer C. Dhamne
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Meera E. Modi
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Audrey Gray
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | - Simone Bonazzi
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | - Lucas Craig
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | - Elizabeth Bainbridge
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Lahin Lalani
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Chloe E. Super
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Samantha Schaeffer
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Ketthsy Capre
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | - Danuta Lubicka
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | - Guiqing Liang
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | - Doug Burdette
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | | | - Sarika Gurnani
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Sheryl Anne D. Vermudez
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Daniel Curtis
- Novartis Institutes for Biomedical ResearchCambridgeMassachusettsUSA
| | | | - Mustafa Q. Hameed
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Angelica D'Amore
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Alexander Rotenberg
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Mustafa Sahin
- F.M. Kirby Neurobiology Center, Rosamund Stone Zander Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| |
Collapse
|
4
|
Yu C, Deng XJ, Xu D. Microglia in epilepsy. Neurobiol Dis 2023; 185:106249. [PMID: 37536386 DOI: 10.1016/j.nbd.2023.106249] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/07/2023] [Accepted: 07/31/2023] [Indexed: 08/05/2023] Open
Abstract
Epilepsy is one of most common chronic neurological disorders, and the antiseizure medications developed by targeting neurocentric mechanisms have not effectively reduced the proportion of patients with drug-resistant epilepsy. Further exploration of the cellular or molecular mechanism of epilepsy is expected to provide new options for treatment. Recently, more and more researches focus on brain network components other than neurons, among which microglia have attracted much attention for their diverse biological functions. As the resident immune cells of the central nervous system, microglia have highly plastic transcription, morphology and functional characteristics, which can change dynamically in a context-dependent manner during the progression of epilepsy. In the pathogenesis of epilepsy, highly reactive microglia interact with other components in the epileptogenic network by performing crucial functions such as secretion of soluble factors and phagocytosis, thus continuously reshaping the landscape of the epileptic brain microenvironment. Indeed, microglia appear to be both pro-epileptic and anti-epileptic under the different spatiotemporal contexts of disease, rendering interventions targeting microglia biologically complex and challenging. This comprehensive review critically summarizes the pathophysiological role of microglia in epileptic brain homeostasis alterations and explores potential therapeutic or modulatory targets for epilepsy targeting microglia.
Collapse
Affiliation(s)
- Cheng Yu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China
| | - Xue-Jun Deng
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China
| | - Da Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China.
| |
Collapse
|
5
|
Lafourcade CA, Sparks FT, Bordey A, Wyneken U, Mohammadi MH. Cannabinoid regulation of neurons in the dentate gyrus during epileptogenesis: Role of CB1R-associated proteins and downstream pathways. Epilepsia 2023. [PMID: 36869624 DOI: 10.1111/epi.17569] [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: 10/11/2022] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 03/05/2023]
Abstract
The hippocampal formation plays a central role in the development of temporal lobe epilepsy (TLE), a disease characterized by recurrent, unprovoked epileptic discharges. TLE is a neurologic disorder characterized by acute long-lasting seizures (i.e., abnormal electrical activity in the brain) or seizures that occur in close proximity without recovery, typically after a brain injury or status epilepticus. After status epilepticus, epileptogenic hyperexcitability develops gradually over the following months to years, resulting in the emergence of chronic, recurrent seizures. Acting as a filter or gate, the hippocampal dentate gyrus (DG) normally prevents excessive excitation from propagating through the hippocampus, and is considered a critical region in the progression of epileptogenesis in pathological conditions. Importantly, lipid-derived endogenous cannabinoids (endocannabinoids), which are produced on demand as retrograde messengers, are central regulators of neuronal activity in the DG circuit. In this review, we summarize recent findings concerning the role of the DG in controlling hyperexcitability and propose how DG regulation by cannabinoids (CBs) could provide avenues for therapeutic interventions. We also highlight possible pathways and manipulations that could be relevant for the control of hyperexcitation. The use of CB compounds to treat epilepsies is controversial, as anecdotal evidence is not always validated by clinical trials. Recent publications shed light on the importance of the DG as a region regulating incoming hippocampal excitability during epileptogenesis. We review recent findings concerning the modulation of the hippocampal DG circuitry by CBs and discuss putative underlying pathways. A better understanding of the mechanisms by which CBs exert their action during seizures may be useful to improve therapies.
Collapse
Affiliation(s)
- Carlos A Lafourcade
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, China
| | - Fraser T Sparks
- Department of Neuroscience, Columbia University, New York, New York, USA.,Current: Regeneron Pharmaceuticals, Tarrytown, New York, USA
| | - Angelique Bordey
- Department of Neurosurgery, Yale School of Medicine, New Haven, Connecticut, USA
| | - Ursula Wyneken
- Centro de Investigación e Innovación Biomédica, Laboratorio de Neurociencias, Universidad de Los Andes, Santiago, Chile.,Center of Interventional Medicine for Precision and Advanced Cellular Therapy, Santiago, Chile
| | | |
Collapse
|
6
|
Ots HD, Anderson T, Sherrerd-Smith W, DelBianco J, Rasic G, Chuprin A, Toor Z, Fitch E, Ahuja K, Reid F, Musto AE. Scoping review of disease-modifying effect of drugs in experimental epilepsy. Front Neurol 2023; 14:1097473. [PMID: 36908628 PMCID: PMC9997527 DOI: 10.3389/fneur.2023.1097473] [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: 11/13/2022] [Accepted: 02/02/2023] [Indexed: 02/25/2023] Open
Abstract
Objective Epilepsy affects ~50 million people worldwide causing significant medical, financial, and sociologic concerns for affected patients and their families. To date, treatment of epilepsy is primarily symptomatic management because few effective preventative or disease-modifying interventions exist. However, recent research has identified neurobiological mechanisms of epileptogenesis, providing new pharmacologic targets to investigate. The current scientific evidence remains scattered across multiple studies using different model and experimental designs. The review compiles different models of anti-epileptogenic investigation and highlights specific compounds with potential epileptogenesis-modifying experimental drugs. It provides a platform for standardization of future epilepsy research to allow a more robust compound analysis of compounds with potential for epilepsy prevention. Methods PubMed, Ovid MEDLINE, and Web of Science were searched from 2007 to 2021. Studies with murine models of epileptogenesis and explicitly detailed experimental procedures were included in the scoping review. In total, 51 articles were selected from 14,983 and then grouped by five core variables: (1) seizure frequency, (2) seizure severity, (3) spontaneous recurrent seizures (SRS), (4) seizure duration, and (5) mossy fiber sprouting (MFS). The variables were differentiated based on experimental models including methods of seizure induction, treatment schedule and timeline of data collection. Data was categorized by the five core variables and analyzed by converting original treatment values to units of percent of its respective control. Results Discrepancies in current epileptogenesis models significantly complicate inter-study comparison of potential anti-epileptogenic interventions. With our analysis, many compounds showed a potential to reduce epileptogenic characteristics defined by the five core variables. WIN55,212-2, aspirin, rapamycin, 1400W, and LEV + BQ788 were identified compounds with the potential of effective anti-epileptic properties. Significance Our review highlights the need for consistent methodology in epilepsy research and provides a novel approach for future research. Inconsistent experimental designs hinder study comparison, slowing the progression of treatments for epilepsy. If the research community can optimize and standardize parameters such as methods of seizure induction, administration schedule, sampling time, and aniMal models, more robust meta-analysis and collaborative research would follow. Additionally, some compounds such as rapamycin, WIN 55,212-2, aspirin, 1400W, and LEV + BQ788 showed anti-epileptogenic modulation across multiple variables. We believe they warrant further study both individually and synergistically.
Collapse
Affiliation(s)
- Heather D Ots
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Taylor Anderson
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | | | - John DelBianco
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Gordana Rasic
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Anthony Chuprin
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Zeeshan Toor
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Elizabeth Fitch
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Kripa Ahuja
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Faith Reid
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Alberto E Musto
- Department of Pathology and Anatomy, Eastern Virginia Medical School, Norfolk, VA, United States.,Department of Neurology, Eastern Virginia Medical School, Norfolk, VA, United States
| |
Collapse
|
7
|
Löscher W, Stafstrom CE. Epilepsy and its neurobehavioral comorbidities: Insights gained from animal models. Epilepsia 2023; 64:54-91. [PMID: 36197310 DOI: 10.1111/epi.17433] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 10/04/2022] [Accepted: 10/04/2022] [Indexed: 01/21/2023]
Abstract
It is well established that epilepsy is associated with numerous neurobehavioral comorbidities, with a bidirectional relationship; people with epilepsy have an increased incidence of depression, anxiety, learning and memory difficulties, and numerous other psychosocial challenges, and the occurrence of epilepsy is higher in individuals with those comorbidities. Although the cause-and-effect relationship is uncertain, a fuller understanding of the mechanisms of comorbidities within the epilepsies could lead to improved therapeutics. Here, we review recent data on epilepsy and its neurobehavioral comorbidities, discussing mainly rodent models, which have been studied most extensively, and emphasize that clinically relevant information can be gained from preclinical models. Furthermore, we explore the numerous potential factors that may confound the interpretation of emerging data from animal models, such as the specific seizure induction method (e.g., chemical, electrical, traumatic, genetic), the role of species and strain, environmental factors (e.g., laboratory environment, handling, epigenetics), and the behavioral assays that are chosen to evaluate the various aspects of neural behavior and cognition. Overall, the interplay between epilepsy and its neurobehavioral comorbidities is undoubtedly multifactorial, involving brain structural changes, network-level differences, molecular signaling abnormalities, and other factors. Animal models are well poised to help dissect the shared pathophysiological mechanisms, neurological sequelae, and biomarkers of epilepsy and its comorbidities.
Collapse
Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Carl E Stafstrom
- Division of Pediatric Neurology, Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
8
|
Morawe MP, Liao F, Amberg W, van Bergeijk J, Chang R, Gulino M, Hamilton C, Hoft C, Lumpkin C, Mastis B, McGlame E, Nuber J, Plaas C, Ravikumar B, Roy K, Schanzenbächer M, Tierno J, Lakics V, Dellovade T, Townsend M. Pharmacological mTOR-inhibition facilitates clearance of AD-related tau aggregates in the mouse brain. Eur J Pharmacol 2022; 934:175301. [DOI: 10.1016/j.ejphar.2022.175301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 11/03/2022]
|
9
|
Impact of Raptor and Rictor Deletion on Hippocampal Pathology Following Status Epilepticus. J Mol Neurosci 2022; 72:1243-1258. [PMID: 35618880 PMCID: PMC9571976 DOI: 10.1007/s12031-022-02030-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/17/2022] [Indexed: 10/18/2022]
Abstract
Neuronal hyperactivation of the mTOR signaling pathway may play a role in driving the pathological sequelae that follow status epilepticus. Animal studies using pharmacological tools provide support for this hypothesis, however, systemic inhibition of mTOR-a growth pathway active in every mammalian cell-limits conclusions on cell type specificity. To circumvent the limitations of pharmacological approaches, we developed a viral/genetic strategy to delete Raptor or Rictor, inhibiting mTORC1 or mTORC2, respectively, from excitatory hippocampal neurons after status epilepticus in mice. Raptor or Rictor was deleted from roughly 25% of hippocampal granule cells, with variable involvement of other hippocampal neurons, after pilocarpine status epilepticus. Status epilepticus induced the expected loss of hilar neurons, sprouting of granule cell mossy fiber axons and reduced c-Fos activation. Gene deletion did not prevent these changes, although Raptor loss reduced the density of c-Fos-positive granule cells overall relative to Rictor groups. Findings demonstrate that mTOR signaling can be effectively modulated with this approach and further reveal that blocking mTOR signaling in a minority (25%) of granule cells is not sufficient to alter key measures of status epilepticus-induced pathology. The approach is suitable for producing higher deletion rates, and altering the timing of deletion, which may lead to different outcomes.
Collapse
|
10
|
Vyas P, Tulsawani R, Vohora D. Dual Targeting by Inhibition of Phosphoinositide-3-Kinase and Mammalian Target of Rapamycin Attenuates the Neuroinflammatory Responses in Murine Hippocampal Cells and Seizures in C57BL/6 Mice. Front Immunol 2021; 12:739452. [PMID: 34887852 PMCID: PMC8650161 DOI: 10.3389/fimmu.2021.739452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 10/04/2021] [Indexed: 11/25/2022] Open
Abstract
Emerging evidence suggests the association of seizures and inflammation; however, underlying cell signaling mechanisms are still not fully understood. Overactivation of phosphoinositide-3-kinases is associated with both neuroinflammation and seizures. Herein, we speculate the PI3K/Akt/mTOR pathway as a promising therapeutic target for neuroinflammation-mediated seizures and associated neurodegeneration. Firstly, we cultured HT22 cells for detection of the downstream cell signaling events activated in a lipopolysaccharide (LPS)-primed pilocarpine (PILO) model. We then evaluated the effects of 7-day treatment of buparlisib (PI3K inhibitor, 25 mg/kg p.o.), dactolisib (PI3K/mTOR inhibitor, 25 mg/kg p.o.), and rapamycin (mTORC1 inhibitor, 10 mg/kg p.o.) in an LPS-primed PILO model of seizures in C57BL/6 mice. LPS priming resulted in enhanced seizure severity and reduced latency. Buparlisib and dactolisib, but not rapamycin, prolonged latency to seizures and reduced neuronal loss, while all drugs attenuated seizure severity. Buparlisib and dactolisib further reduced cellular redox, mitochondrial membrane potential, cleaved caspase-3 and p53, nuclear integrity, and attenuated NF-κB, IL-1β, IL-6, TNF-α, and TGF-β1 and TGF-β2 signaling both in vitro and in vivo post-PILO and LPS+PILO inductions; however, rapamycin mitigated the same only in the PILO model. Both drugs protected against neuronal cell death demonstrating the contribution of this pathway in the seizure-induced neuronal pyknosis; however, rapamycin showed resistance in a combination model. Furthermore, LPS and PILO exposure enhanced pAkt/Akt and phospho-p70S6/total-p70S6 kinase activity, while buparlisib and dactolisib, but not rapamycin, could reduce it in a combination model. Partial rapamycin resistance was observed possibly due to the reactivation of the pathway by a functionally different complex of mTOR, i.e., mTORC2. Our study substantiated the plausible involvement of PI3K-mediated apoptotic and inflammatory pathways in LPS-primed PILO-induced seizures and provides evidence that its modulation constitutes an anti-inflammatory mechanism by which seizure inhibitory effects are observed. We showed dual inhibition by dactolisib as a promising approach. Targeting this pathway at two nodes at a time may provide new avenues for antiseizure therapies.
Collapse
Affiliation(s)
- Preeti Vyas
- Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India
| | - Rajkumar Tulsawani
- Defense Institute of Physiology & Allied Science, Defense Research and Development Organization, New Delhi, India
| | - Divya Vohora
- Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India
| |
Collapse
|
11
|
Selected Molecular Targets for Antiepileptogenesis. Int J Mol Sci 2021; 22:ijms22189737. [PMID: 34575901 PMCID: PMC8466306 DOI: 10.3390/ijms22189737] [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: 08/05/2021] [Revised: 09/02/2021] [Accepted: 09/02/2021] [Indexed: 02/07/2023] Open
Abstract
The term epileptogenesis defines the usually durable process of converting normal brain into an epileptic one. The resistance of a significant proportion of patients with epilepsy to the available pharmacotherapy prompted the concept of a causative treatment option consisting in stopping or modifying the progress of epileptogenesis. Most antiepileptic drugs possess only a weak or no antiepileptogenic potential at all, but a few of them appear promising in this regard; these include, for example, eslicarbazepine (a sodium and T-type channel blocker), lamotrigine (a sodium channel blocker and glutamate antagonist) or levetiracetam (a ligand of synaptic vehicle protein SV2A). Among the approved non-antiepileptic drugs, antiepileptogenic potential seems to reside in losartan (a blocker of angiotensin II type 1 receptors), biperiden (an antiparkinsonian drug), nonsteroidal anti-inflammatory drugs, antioxidative drugs and minocycline (a second-generation tetracycline with anti-inflammatory and antioxidant properties). Among other possible antiepileptogenic compounds, antisense nucleotides have been considered, among these an antagomir targeting microRNA-134. The drugs and agents mentioned above have been evaluated in post-status epilepticus models of epileptogenesis, so their preventive efficacy must be verified. Limited clinical data indicate that biperiden in patients with brain injuries is well-tolerated and seems to reduce the incidence of post-traumatic epilepsy. Exceptionally, in this regard, our own original data presented here point to c-Fos as an early seizure duration, but not seizure intensity-related, marker of early epileptogenesis. Further research of reliable markers of early epileptogenesis is definitely needed to improve the process of designing adequate antiepileptogenic therapies.
Collapse
|
12
|
Welzel L, Bergin DH, Schidlitzki A, Twele F, Johne M, Klein P, Löscher W. Systematic evaluation of rationally chosen multitargeted drug combinations: a combination of low doses of levetiracetam, atorvastatin and ceftriaxone exerts antiepileptogenic effects in a mouse model of acquired epilepsy. Neurobiol Dis 2020; 149:105227. [PMID: 33347976 DOI: 10.1016/j.nbd.2020.105227] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 11/24/2020] [Accepted: 12/16/2020] [Indexed: 01/22/2023] Open
Abstract
Epileptogenesis, the gradual process that leads to epilepsy after brain injury or genetic mutations, is a complex network phenomenon, involving a variety of morphological, biochemical and functional brain alterations. Although risk factors for developing epilepsy are known, there is currently no treatment available to prevent epilepsy. We recently proposed a multitargeted, network-based approach to prevent epileptogenesis by rationally combining clinically available drugs and provided first proof-of-concept that this strategy is effective. Here we evaluated eight novel rationally chosen combinations of 14 drugs with mechanisms that target different epileptogenic processes. The combinations consisted of 2-4 different drugs per combination and were administered systemically over 5 days during the latent epileptogenic period in the intrahippocampal kainate mouse model of acquired temporal lobe epilepsy, starting 6 h after kainate. Doses and dosing intervals were based on previous pharmacokinetic and tolerability studies in mice. The incidence and frequency of spontaneous electrographic and electroclinical seizures were recorded by continuous (24/7) video linked EEG monitoring done for seven days at 4 and 12 weeks post-kainate, i.e., long after termination of drug treatment. Compared to vehicle controls, the most effective drug combination consisted of low doses of levetiracetam, atorvastatin and ceftriaxone, which markedly reduced the incidence of electrographic seizures (by 60%; p<0.05) and electroclinical seizures (by 100%; p<0.05) recorded at 12 weeks after kainate. This effect was lost when higher doses of the three drugs were administered, indicating a synergistic drug-drug interaction at the low doses. The potential mechanisms underlying this interaction are discussed. We have discovered a promising novel multitargeted combination treatment for modifying the development of acquired epilepsy.
Collapse
Affiliation(s)
- Lisa Welzel
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - David H Bergin
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Alina Schidlitzki
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Friederike Twele
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Marie Johne
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Pavel Klein
- Mid-Atlantic Epilepsy and Sleep Center, Bethesda, MD, USA
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| |
Collapse
|
13
|
Insights into Potential Targets for Therapeutic Intervention in Epilepsy. Int J Mol Sci 2020; 21:ijms21228573. [PMID: 33202963 PMCID: PMC7697405 DOI: 10.3390/ijms21228573] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/04/2020] [Accepted: 11/11/2020] [Indexed: 02/06/2023] Open
Abstract
Epilepsy is a chronic brain disease that affects approximately 65 million people worldwide. However, despite the continuous development of antiepileptic drugs, over 30% patients with epilepsy progress to drug-resistant epilepsy. For this reason, it is a high priority objective in preclinical research to find novel therapeutic targets and to develop effective drugs that prevent or reverse the molecular mechanisms underlying epilepsy progression. Among these potential therapeutic targets, we highlight currently available information involving signaling pathways (Wnt/β-catenin, Mammalian Target of Rapamycin (mTOR) signaling and zinc signaling), enzymes (carbonic anhydrase), proteins (erythropoietin, copine 6 and complement system), channels (Transient Receptor Potential Vanilloid Type 1 (TRPV1) channel) and receptors (galanin and melatonin receptors). All of them have demonstrated a certain degree of efficacy not only in controlling seizures but also in displaying neuroprotective activity and in modifying the progression of epilepsy. Although some research with these specific targets has been done in relation with epilepsy, they have not been fully explored as potential therapeutic targets that could help address the unsolved issue of drug-resistant epilepsy and develop new antiseizure therapies for the treatment of epilepsy.
Collapse
|
14
|
Novel brain permeant mTORC1/2 inhibitors are as efficacious as rapamycin or everolimus in mouse models of acquired partial epilepsy and tuberous sclerosis complex. Neuropharmacology 2020; 180:108297. [PMID: 32890589 DOI: 10.1016/j.neuropharm.2020.108297] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/27/2020] [Accepted: 09/01/2020] [Indexed: 12/24/2022]
Abstract
Mechanistic target of rapamycin (mTOR) regulates cell proliferation, growth and survival, and is activated in cancer and neurological disorders, including epilepsy. The rapamycin derivative ("rapalog") everolimus, which allosterically inhibits the mTOR pathway, is approved for the treatment of partial epilepsy with spontaneous recurrent seizures (SRS) in individuals with tuberous sclerosis complex (TSC). In contrast to the efficacy in TSC, the efficacy of rapalogs on SRS in other types of epilepsy is equivocal. Furthermore, rapalogs only poorly penetrate into the brain and are associated with peripheral adverse effects, which may compromise their therapeutic efficacy. Here we compare the antiseizure efficacy of two novel, brain-permeable ATP-competitive and selective mTORC1/2 inhibitors, PQR620 and PQR626, and the selective dual pan-PI3K/mTORC1/2 inhibitor PQR530 in two mouse models of chronic epilepsy with SRS, the intrahippocampal kainate (IHK) mouse model of acquired temporal lobe epilepsy and Tsc1GFAP CKO mice, a well-characterized mouse model of epilepsy in TSC. During prolonged treatment of IHK mice with rapamycin, everolimus, PQR620, PQR626, or PQR530; only PQR620 exerted a transient antiseizure effect on SRS, at well tolerated doses whereas the other compounds were ineffective. In contrast, all of the examined compounds markedly suppressed SRS in Tsc1GFAP CKO mice during chronic treatment at well tolerated doses. Thus, against our expectation, no clear differences in antiseizure efficacy were found across the three classes of mTOR inhibitors examined in mouse models of genetic and acquired epilepsies. The main advantage of the novel 1,3,5-triazine derivatives is their excellent tolerability compared to rapalogs, which would favor their development as new therapies for TORopathies such as TSC.
Collapse
|
15
|
Microglial mTOR is Neuronal Protective and Antiepileptogenic in the Pilocarpine Model of Temporal Lobe Epilepsy. J Neurosci 2020; 40:7593-7608. [PMID: 32868461 DOI: 10.1523/jneurosci.2754-19.2020] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 08/05/2020] [Accepted: 08/24/2020] [Indexed: 01/01/2023] Open
Abstract
Excessive activation of mammalian target of rapamycin (mTOR) signaling is epileptogenic in genetic epilepsy. However, the exact role of microglial mTOR in acquired epilepsy remains to be clarified. In the present study, we found that mTOR is strongly activated in microglia following excitatory injury elicited by status epilepticus. To determine the role of microglial mTOR signaling in excitatory injury and epileptogenesis, we generated mice with restrictive deletion of mTOR in microglia. Both male and female mice were used in the present study. We found that mTOR-deficient microglia lost their typical proliferative and inflammatory responses to excitatory injury, whereas the proliferation of astrocytes was preserved. In addition, mTOR-deficient microglia did not effectively engulf injured/dying neurons. More importantly, microglial mTOR-deficient mice displayed increased neuronal loss and developed more severe spontaneous seizures. These findings suggest that microglial mTOR plays a protective role in mitigating neuronal loss and attenuating epileptogenesis in the excitatory injury model of epilepsy.SIGNIFICANCE STATEMENT The mammalian target of rapamycin (mTOR) pathway is strongly implicated in epilepsy. However, the effect of mTOR inhibitors in preclinical models of acquired epilepsy is inconsistent. The broad presence of mTOR signaling in various brain cells could prevent mTOR inhibitors from achieving a net therapeutic effect. This conundrum has spurred further investigation of the cell type-specific effects of mTOR signaling in the CNS. We found that activation of microglial mTOR is antiepileptogenic. Thus, microglial mTOR activation represents a novel antiepileptogenic route that appears to parallel the proepileptogenic route of neuronal mTOR activation. This may explain why the net effect of mTOR inhibitors is paradoxical in the acquired models of epilepsy. Our findings could better guide the use of mTOR inhibitors in preventing acquired epilepsy.
Collapse
|
16
|
Miziak B, Konarzewska A, Ułamek-Kozioł M, Dudra-Jastrzębska M, Pluta R, Czuczwar SJ. Anti-Epileptogenic Effects of Antiepileptic Drugs. Int J Mol Sci 2020; 21:ijms21072340. [PMID: 32231010 PMCID: PMC7178140 DOI: 10.3390/ijms21072340] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 03/23/2020] [Accepted: 03/25/2020] [Indexed: 12/12/2022] Open
Abstract
Generally, the prevalence of epilepsy does not exceed 0.9% of the population and approximately 70% of epilepsy patients may be adequately controlled with antiepileptic drugs (AEDs). Moreover, status epilepticus (SE) or even a single seizure may produce neurodegeneration within the brain and SE has been recognized as one of acute brain insults leading to acquired epilepsy via the process of epileptogenesis. Two questions thus arise: (1) Are AEDs able to inhibit SE-induced neurodegeneration? and (2) if so, can a probable neuroprotective potential of particular AEDs stop epileptogenesis? An affirmative answer to the second question would practically point to the preventive potential of a given neuroprotective AED following acute brain insults. The available experimental data indicate that diazepam (at low and high doses), gabapentin, pregabalin, topiramate and valproate exhibited potent or moderate neuroprotective effects in diverse models of SE in rats. However, only diazepam (at high doses), gabapentin and pregabalin exerted some protective activity against acquired epilepsy (spontaneous seizures). As regards valproate, its effects on spontaneous seizures were equivocal. With isobolography, some supra-additive combinations of AEDs have been delineated against experimental seizures. One of such combinations, levetiracetam + topiramate proved highly synergistic in two models of seizures and this particular combination significantly inhibited epileptogenesis in rats following status SE. Importantly, no neuroprotection was evident. It may be strikingly concluded that there is no correlation between neuroprotection and antiepileptogenesis. Probably, preclinically verified combinations of AEDs may be considered for an anti-epileptogenic therapy.
Collapse
Affiliation(s)
- Barbara Miziak
- Department of Pathophysiology, Medical University of Lublin, 20-090 Lublin, Poland; (B.M.); (A.K.); (M.D.-J.)
| | - Agnieszka Konarzewska
- Department of Pathophysiology, Medical University of Lublin, 20-090 Lublin, Poland; (B.M.); (A.K.); (M.D.-J.)
| | - Marzena Ułamek-Kozioł
- Laboratory of Ischemic and Neurodegenerative Brain Research, Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Poland;
| | - Monika Dudra-Jastrzębska
- Department of Pathophysiology, Medical University of Lublin, 20-090 Lublin, Poland; (B.M.); (A.K.); (M.D.-J.)
| | - Ryszard Pluta
- Laboratory of Ischemic and Neurodegenerative Brain Research, Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warsaw, Poland;
- Correspondence: (R.P.); (S.J.C.); Tel.: +48-22-6086-540 (ext. 6086-469) (R.P.); +48-81-448-65-00 (S.J.C.); Fax: +48-81-448-65-01 (S.J.C.); +48-22-6086-627/668-55-32 (R.P.)
| | - Stanisław J. Czuczwar
- Department of Pathophysiology, Medical University of Lublin, 20-090 Lublin, Poland; (B.M.); (A.K.); (M.D.-J.)
- Correspondence: (R.P.); (S.J.C.); Tel.: +48-22-6086-540 (ext. 6086-469) (R.P.); +48-81-448-65-00 (S.J.C.); Fax: +48-81-448-65-01 (S.J.C.); +48-22-6086-627/668-55-32 (R.P.)
| |
Collapse
|