1
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Garg D, Charlesworth L, Shukla G. Sleep and Temporal Lobe Epilepsy – Associations, Mechanisms and Treatment Implications. Front Hum Neurosci 2022; 16:849899. [PMID: 35558736 PMCID: PMC9086778 DOI: 10.3389/fnhum.2022.849899] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
In this systematic review, we aim to describe the association between temporal lobe epilepsy (TLE) and sleep, with bidirectional links in mechanisms and therapeutic aspects. Sleep stages may variably impact seizure occurrence, secondary generalization and the development, frequency and distribution of interictal epileptiform discharges. Conversely, epilepsy affects sleep micro- and macroarchitecture. TLE, the most frequent form of drug resistant epilepsy (DRE), shares an enduring relationship with sleep, with some intriguing potential mechanisms specific to anatomic localization, linking the two. Sleep characteristics of TLE may also inform localizing properties in persons with DRE, since seizures arising from the temporal lobe seem to be more common during wakefulness, compared to seizures of extratemporal origin. Polysomnographic studies indicate that persons with TLE may experience excessive daytime somnolence, disrupted sleep architecture, increased wake after sleep onset, frequent shifts in sleep stages, lower sleep efficiency, decreased rapid eye movement (REM) sleep, and possibly, increased incidence of sleep apnea. Limited literature suggests that effective epilepsy surgery may remedy many of these objective and subjective sleep-related concerns, via multipronged effects, apart from reduced seizure frequency. Additionally, sleep abnormalities also seem to influence memory, language and cognitive-executive function in both medically controlled and refractory TLE. Another aspect of the relationship pertains to anti-seizure medications (ASMs), which may contribute significantly to sleep characteristics and abnormalities in persons with TLE. Literature focused on specific aspects of TLE and sleep is limited, and heterogeneous. Future investigations are essential to understand the pathogenetic mechanisms linking sleep abnormalities on epilepsy outcomes in the important sub-population of TLE.
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Affiliation(s)
- Divyani Garg
- Department of Neurology, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India
| | | | - Garima Shukla
- Division of Epilepsy and Sleep Medicine, Queen’s University, Kingston, ON, Canada
- *Correspondence: Garima Shukla,
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2
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Tse K, Beamer E, Simpson D, Beynon RJ, Sills GJ, Thippeswamy T. The Impacts of Surgery and Intracerebral Electrodes in C57BL/6J Mouse Kainate Model of Epileptogenesis: Seizure Threshold, Proteomics, and Cytokine Profiles. Front Neurol 2021; 12:625017. [PMID: 34322075 PMCID: PMC8312573 DOI: 10.3389/fneur.2021.625017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 06/07/2021] [Indexed: 01/01/2023] Open
Abstract
Intracranial electroencephalography (EEG) is commonly used to study epileptogenesis and epilepsy in experimental models. Chronic gliosis and neurodegeneration at the injury site are known to be associated with surgically implanted electrodes in both humans and experimental models. Currently, however, there are no reports on the impact of intracerebral electrodes on proteins in the hippocampus and proinflammatory cytokines in the cerebral cortex and plasma in experimental models. We used an unbiased, label-free proteomics approach to identify the altered proteins in the hippocampus, and multiplex assay for cytokines in the cerebral cortex and plasma of C57BL/6J mice following bilateral surgical implantation of electrodes into the cerebral hemispheres. Seven days following surgery, a repeated low dose kainate (KA) regimen was followed to induce status epilepticus (SE). Surgical implantation of electrodes reduced the amount of KA necessary to induce SE by 50%, compared with mice without surgery. Tissues were harvested 7 days post-SE (i.e., 14 days post-surgery) and compared with vehicle-treated mice. Proteomic profiling showed more proteins (103, 6.8% of all proteins identified) with significantly changed expression (p < 0.01) driven by surgery than by KA treatment itself without surgery (27, 1.8% of all proteins identified). Further, electrode implantation approximately doubled the number of KA-induced changes in protein expression (55, 3.6% of all identified proteins). Further analysis revealed that intracerebral electrodes and KA altered the expression of proteins associated with epileptogenesis such as inflammation (C1q system), neurodegeneration (cystatin-C, galectin-1, cathepsin B, heat-shock protein 25), blood–brain barrier dysfunction (fibrinogen-α, serum albumin, α2 macroglobulin), and gliosis (vimentin, GFAP, filamin-A). The multiplex assay revealed a significant increase in key cytokines such as TNFα, IL-1β, IL-4, IL-5, IL-6, IL-10, IL12p70, IFN-γ, and KC/GRO in the cerebral cortex and some in the plasma in the surgery group. Overall, these findings demonstrate that surgical implantation of depth electrodes alters some of the molecules that may have a role in epileptogenesis in experimental models.
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Affiliation(s)
- Karen Tse
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom.,Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Edward Beamer
- Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Deborah Simpson
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Robert J Beynon
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Graeme J Sills
- Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Thimmasettappa Thippeswamy
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
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3
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Datta D, Subburaju S, Kaye S, Baruah J, Choi YK, Nian Y, Khalili JS, Chung S, Elkhal A, Vasudevan A. Human forebrain endothelial cell therapy for psychiatric disorders. Mol Psychiatry 2021; 26:4864-4883. [PMID: 32661257 PMCID: PMC8162704 DOI: 10.1038/s41380-020-0839-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 06/23/2020] [Accepted: 07/03/2020] [Indexed: 12/30/2022]
Abstract
Abnormalities of or reductions in GABAergic interneurons are implicated in the pathology of severe neuropsychiatric disorders, for which effective treatments are still elusive. Transplantation of human stem cell-derived interneurons is a promising cell-based therapy for treatment of these disorders. In mouse xenograft studies, human stem cell-derived-interneuron precursors could differentiate in vivo, but required a prolonged time of four to seven months to migrate from the graft site and integrate with the host tissue. This poses a serious roadblock for clinical translation of this approach. For transplantation to be effective, grafted neurons should migrate to affected areas at a faster rate. We have previously shown that endothelial cells of the periventricular vascular network are the natural substrates for GABAergic interneurons in the developing mouse forebrain, and provide valuable guidance cues for their long-distance migration. In addition, periventricular endothelial cells house a GABA signaling pathway with direct implications for psychiatric disease origin. In this study we translated this discovery into human, with significant therapeutic implications. We generated human periventricular endothelial cells, using human pluripotent stem cell technology, and extensively characterized its molecular, cellular, and functional properties. Co-culture of human periventricular endothelial cells with human interneurons significantly accelerated interneuron migration in vitro and led to faster migration and wider distribution of grafted interneurons in vivo, compared to neuron-only transplants. Furthermore, the co-transplantation strategy was able to rescue abnormal behavioral symptoms in a pre-clinical model of psychiatric disorder, within 1 month after transplantation. We anticipate this strategy to open new doors and facilitate exciting advances in angiogenesis-mediated treatment of psychiatric disorders.
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Affiliation(s)
- Debkanya Datta
- grid.280933.30000 0004 0452 8371Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA 91105 USA ,grid.38142.3c000000041936754XDepartment of Psychiatry, Harvard Medical School, Boston, MA 02215 USA ,grid.240206.20000 0000 8795 072XDivision of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478 USA
| | - Sivan Subburaju
- grid.280933.30000 0004 0452 8371Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA 91105 USA ,grid.38142.3c000000041936754XDepartment of Psychiatry, Harvard Medical School, Boston, MA 02215 USA ,grid.240206.20000 0000 8795 072XDivision of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478 USA
| | - Sarah Kaye
- grid.280933.30000 0004 0452 8371Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA 91105 USA ,grid.240206.20000 0000 8795 072XDivision of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478 USA
| | - Jugajyoti Baruah
- grid.280933.30000 0004 0452 8371Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA 91105 USA ,grid.38142.3c000000041936754XDepartment of Psychiatry, Harvard Medical School, Boston, MA 02215 USA ,grid.240206.20000 0000 8795 072XDivision of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478 USA
| | - Yong Kee Choi
- grid.280933.30000 0004 0452 8371Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA 91105 USA ,grid.38142.3c000000041936754XDepartment of Psychiatry, Harvard Medical School, Boston, MA 02215 USA ,grid.240206.20000 0000 8795 072XDivision of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478 USA
| | - Yeqi Nian
- grid.38142.3c000000041936754XDepartment of Surgery, Harvard Medical School, Boston, MA 02115 USA ,grid.62560.370000 0004 0378 8294Division of Transplantation, Brigham and Women’s Hospital, 221 Longwood Avenue, EBRC 309, Boston, MA 02115 USA
| | | | - Sangmi Chung
- grid.260917.b0000 0001 0728 151XDepartment of Cell biology and Anatomy, New York Medical College, Valhalla, NY 10595 USA
| | - Abdallah Elkhal
- grid.38142.3c000000041936754XDepartment of Surgery, Harvard Medical School, Boston, MA 02115 USA ,grid.62560.370000 0004 0378 8294Division of Transplantation, Brigham and Women’s Hospital, 221 Longwood Avenue, EBRC 309, Boston, MA 02115 USA
| | - Anju Vasudevan
- Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA, 91105, USA. .,Department of Psychiatry, Harvard Medical School, Boston, MA, 02215, USA. .,Division of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA, 02478, USA.
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Bröer S. Not Part of the Temporal Lobe, but Still of Importance? Substantia Nigra and Subthalamic Nucleus in Epilepsy. Front Syst Neurosci 2020; 14:581826. [PMID: 33381016 PMCID: PMC7768985 DOI: 10.3389/fnsys.2020.581826] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 11/09/2020] [Indexed: 01/15/2023] Open
Abstract
The most researched brain region in epilepsy research is the temporal lobe, and more specifically, the hippocampus. However, numerous other brain regions play a pivotal role in seizure circuitry and secondary generalization of epileptic activity: The substantia nigra pars reticulata (SNr) and its direct input structure, the subthalamic nucleus (STN), are considered seizure gating nuclei. There is ample evidence that direct inhibition of the SNr is capable of suppressing various seizure types in experimental models. Similarly, inhibition via its monosynaptic glutamatergic input, the STN, can decrease seizure susceptibility as well. This review will focus on therapeutic interventions such as electrical stimulation and targeted drug delivery to SNr and STN in human patients and experimental animal models of epilepsy, highlighting the opportunities for overcoming pharmacoresistance in epilepsy by investigating these promising target structures.
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Affiliation(s)
- Sonja Bröer
- Faculty of Veterinary Medicine, Institute of Pharmacology and Toxicology, Freie Universität Berlin, Berlin, Germany
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5
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Baruah J, Vasudevan A, Köhling R. Vascular Integrity and Signaling Determining Brain Development, Network Excitability, and Epileptogenesis. Front Physiol 2020; 10:1583. [PMID: 32038280 PMCID: PMC6987412 DOI: 10.3389/fphys.2019.01583] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 12/17/2019] [Indexed: 01/27/2023] Open
Abstract
Our understanding of the etiological mechanisms leading up to epilepsy has undergone radical changes over time due to more insights into the complexity of the disease. The traditional hypothesis emphasized network hyperexcitability and an imbalance of inhibition and excitation, eventually leading to seizures. In this context, the contribution of the vascular system, and particularly the interactions between blood vessels and neuronal tissue, came into focus only recently. Thus, one highly exciting causative or contributing factor of epileptogenesis is the disruption of the blood-brain barrier (BBB) in the context of not only posttraumatic epilepsy, but also other etiologies. This hypothesis is now recognized as a synergistic mechanism that can give rise to epilepsy, and BBB repair for restoration of cerebrovascular integrity is considered a therapeutic alternative. Endothelial cells lining the inner surface of blood vessels are an integral component of the BBB system. Sealed by tight junctions, they are crucial in maintaining homeostatic activities of the brain, as well as acting as an interface in the neurovascular unit. Additional potential vascular mechanisms such as inflammation, altered neurovascular coupling, or changes in blood flow that can modulate neuronal circuit activity have been implicated in epilepsy. Our own work has shown how intrinsic defects within endothelial cells from the earliest developmental time points, which preclude neuronal changes, can lead to vascular abnormalities and autonomously support the development of hyperexcitability and epileptiform activity. In this article, we review the importance of vascular integrity and signaling for network excitability and epilepsy by highlighting complementary basic and clinical research studies and by outlining possible novel therapeutic strategies.
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Affiliation(s)
- Jugajyoti Baruah
- Department of Psychiatry, Harvard Medical School, Boston, MA, United States.,Angiogenesis and Brain Development Laboratory, Division of Basic Neuroscience, McLean Hospital, Belmont, MA, United States
| | - Anju Vasudevan
- Department of Psychiatry, Harvard Medical School, Boston, MA, United States.,Angiogenesis and Brain Development Laboratory, Division of Basic Neuroscience, McLean Hospital, Belmont, MA, United States
| | - Rüdiger Köhling
- Oscar-Langendorff-Institute of Physiology, Rostock University Medical Center, Rostock, Germany
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6
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Zhang K, Li Y, Gong H, Liang P, Zhang P. The role of the substantia nigra pars reticulata anterior in amygdala-kindled seizures. Brain Res 2019; 1715:84-93. [DOI: 10.1016/j.brainres.2019.03.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 03/13/2019] [Accepted: 03/15/2019] [Indexed: 11/26/2022]
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7
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Backofen-Wehrhahn B, Gey L, Bröer S, Petersen B, Schiff M, Handreck A, Stanslowsky N, Scharrenbroich J, Weißing M, Staege S, Wegner F, Niemann H, Löscher W, Gernert M. Anticonvulsant effects after grafting of rat, porcine, and human mesencephalic neural progenitor cells into the rat subthalamic nucleus. Exp Neurol 2018; 310:70-83. [PMID: 30205107 DOI: 10.1016/j.expneurol.2018.09.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 08/20/2018] [Accepted: 09/07/2018] [Indexed: 12/11/2022]
Abstract
Cell transplantation based therapy is a promising strategy for treating intractable epilepsies. Inhibition of the subthalamic nucleus (STN) or substantia nigra pars reticulata (SNr) is a powerful experimental approach for remote control of different partial seizure types, when targeting the seizure focus is not amenable. Here, we tested the hypothesis that grafting of embryonic/fetal neural precursor cells (NPCs) from various species (rat, human, pig) into STN or SNr of adult rats induces anticonvulsant effects. To rationally refine this approach, we included NPCs derived from the medial ganglionic eminence (MGE) and ventral mesencephalon (VM), both of which are able to develop a GABAergic phenotype. All VM- and MGE-derived cells showed intense migration behavior after grafting into adult rats, developed characteristics of inhibitory interneurons, and survived at least up to 4 months after transplantation. By using the intravenous pentylenetetrazole (PTZ) seizure threshold test in adult rats, transient anticonvulsant effects were observed after bilateral grafting of NPCs derived from human and porcine VM into STN, but not after SNr injection (site-specificity). In contrast, MGE-derived NPCs did not cause anticonvulsant effects after grafting into STN or SNr (cell-specificity). Neither induction of status epilepticus by lithium-pilocarpine to induce neuronal damage prior to the PTZ test nor pretreatment of MGE cells with retinoic acid and potassium chloride to increase differentiation into GABAergic neurons could enhance anticonvulsant effectiveness of MGE cells. This is the first proof-of-principle study showing anticonvulsant effects by bilateral xenotransplantation of NPCs into the STN. Our study highlights the value of VM-derived NPCs for interneuron-based cell grafting targeting the STN.
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Affiliation(s)
- Bianca Backofen-Wehrhahn
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Laura Gey
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Sonja Bröer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Björn Petersen
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut, Mariensee, Germany
| | - Miriam Schiff
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Annelie Handreck
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | | | - Jessica Scharrenbroich
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Michael Weißing
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Selma Staege
- Center for Systems Neuroscience, Hannover, Germany; Department of Neurology, Hannover Medical School, Hannover, Germany
| | - Florian Wegner
- Center for Systems Neuroscience, Hannover, Germany; Department of Neurology, Hannover Medical School, Hannover, Germany
| | - Heiner Niemann
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut, Mariensee, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Manuela Gernert
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
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8
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GABA-ergic cell therapy for epilepsy: Advances, limitations and challenges. Neurosci Biobehav Rev 2015; 62:35-47. [PMID: 26748379 DOI: 10.1016/j.neubiorev.2015.12.014] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 11/06/2015] [Accepted: 12/28/2015] [Indexed: 01/04/2023]
Abstract
Diminution in the number of gamma-amino butyric acid positive (GABA-ergic) interneurons and their axon terminals, and/or alterations in functional inhibition are conspicuous brain alterations believed to contribute to the persistence of seizures in acquired epilepsies such as temporal lobe epilepsy. This has steered a perception that replacement of lost GABA-ergic interneurons would improve inhibitory synaptic neurotransmission in the epileptic brain region and thereby reduce the occurrence of seizures. Indeed, studies using animal prototypes have reported that grafting of GABA-ergic progenitors derived from multiple sources into epileptic regions can reduce seizures. This review deliberates recent advances, limitations and challenges concerning the development of GABA-ergic cell therapy for epilepsy. The efficacy and limitations of grafts of primary GABA-ergic progenitors from the embryonic lateral ganglionic eminence and medial ganglionic eminence (MGE), neural stem/progenitor cells expanded from MGE, and MGE-like progenitors generated from human pluripotent stem cells for alleviating seizures and co-morbidities of epilepsy are conferred. Additional studies required for possible clinical application of GABA-ergic cell therapy for epilepsy are also summarized.
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9
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Xu AJ, Liu TT, He ZG, Hong QX, Xiang HB. STN-PPTg circuits and REM sleep dysfunction in drug-refractory epilepsy. Epilepsy Behav 2015; 51:277-80. [PMID: 26312990 DOI: 10.1016/j.yebeh.2015.07.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 07/23/2015] [Indexed: 02/07/2023]
Affiliation(s)
- Ai-Jun Xu
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Tao-Tao Liu
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Zhi-Gang He
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Qing-Xiong Hong
- Department of Anesthesiology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou 510120, PR China.
| | - Hong-Bing Xiang
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China.
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Amini E, Rezaei M, Mohamed Ibrahim N, Golpich M, Ghasemi R, Mohamed Z, Raymond AA, Dargahi L, Ahmadiani A. A Molecular Approach to Epilepsy Management: from Current Therapeutic Methods to Preconditioning Efforts. Mol Neurobiol 2014; 52:492-513. [PMID: 25195699 DOI: 10.1007/s12035-014-8876-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Accepted: 08/25/2014] [Indexed: 01/16/2023]
Abstract
Epilepsy is the most common and chronic neurological disorder characterized by recurrent unprovoked seizures. The key aim in treating patients with epilepsy is the suppression of seizures. An understanding of focal changes that are involved in epileptogenesis may therefore provide novel approaches for optimal treatment of the seizure. Although the actual pathogenesis of epilepsy is still uncertain, recently growing lines of evidence declare that microglia and astrocyte activation, oxidative stress and reactive oxygen species (ROS) production, mitochondria dysfunction, and damage of blood-brain barrier (BBB) are involved in its pathogenesis. Impaired GABAergic function in the brain is probably the most accepted hypothesis regarding the pathogenesis of epilepsy. Clinical neuroimaging of patients and experimental modeling have demonstrated that seizures may induce neuronal apoptosis. Apoptosis signaling pathways are involved in the pathogenesis of several types of epilepsy such as temporal lobe epilepsy (TLE). The quality of life of patients is seriously affected by treatment-related problems and also by unpredictability of epileptic seizures. Moreover, the available antiepileptic drugs (AED) are not significantly effective to prevent epileptogenesis. Thus, novel therapies that are proficient to control seizure in people who are suffering from epilepsy are needed. The preconditioning method promises to serve as an alternative therapeutic approach because this strategy has demonstrated the capability to curtail epileptogenesis. For this reason, understanding of molecular mechanisms underlying brain tolerance induced by preconditioning is crucial to delineate new neuroprotective ways against seizure damage and epileptogenesis. In this review, we summarize the work to date on the pathogenesis of epilepsy and discuss recent therapeutic strategies in the treatment of epilepsy. We will highlight that novel therapy targeting such as preconditioning process holds great promise. In addition, we will also highlight the role of gene reprogramming and mitochondrial biogenesis in the preconditioning-mediated neuroprotective events.
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Affiliation(s)
- Elham Amini
- Department of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras, Kuala Lumpur, Malaysia
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11
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Handreck A, Backofen-Wehrhahn B, Bröer S, Löscher W, Gernert M. Anticonvulsant Effects by Bilateral and Unilateral Transplantation of GABA-Producing Cells into the Subthalamic Nucleus in an Acute Seizure Model. Cell Transplant 2014. [DOI: 10.3727/096368912x658944] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Neural transplantation of GABA-producing cells into key structures within seizure-suppressing circuits holds promise for medication-resistant epilepsy patients not eligible for resection of the epileptic focus. The substantia nigra pars reticulata (SNr), a basal ganglia output structure, is well known to modulate different seizure types. A recent microinjection study by our group indicated that the subthalamic nucleus (STN), which critically regulates nigral activity, might be a more promising target for focal therapy in epilepsies than the SNr. As a proof of principle, we therefore assessed the anticonvulsant efficacy of bilateral and unilateral allografting of GABA-producing cell lines into the STN using the timed intravenous pentylenetetrazole seizure threshold test, which allows repeated seizure threshold determinations in individual rats. We observed (a) that grafted cells survived up to the end of the experiments, (b) that anticonvulsant effects can be induced by bilateral transplantation into the STN using immortalized GABAergic cells derived from the rat embryonic striatum and cells additionally transfected to obtain higher GABA synthesis than the parent cell line, and (c) that anticonvulsant effects were observed even after unilateral transplantation into the STN. Neither grafting of control cells nor transplantation outside the STN induced anticonvulsant effects, emphasizing the site and cell specificity of the observed anticonvulsant effects. To our knowledge, the present study is the first showing anticonvulsant effects by grafting of GABA-producing cells into the STN. The STN can be considered a highly promising target region for modulation of seizure circuits and, moreover, has the advantage of being clinically established for functional neurosurgery.
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Affiliation(s)
- Annelie Handreck
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - Bianca Backofen-Wehrhahn
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Sonja Bröer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - Manuela Gernert
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
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12
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Abdanipour A, Tiraihi T, Mirnajafi-Zadeh J. Improvement of the pilocarpine epilepsy model in rat using bone marrow stromal cell therapy. Neurol Res 2013; 33:625-32. [DOI: 10.1179/1743132810y.0000000018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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13
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Garcia I, Kim C, Arenkiel BR. Genetic strategies to investigate neuronal circuit properties using stem cell-derived neurons. Front Cell Neurosci 2012; 6:59. [PMID: 23264761 PMCID: PMC3524522 DOI: 10.3389/fncel.2012.00059] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 11/30/2012] [Indexed: 01/28/2023] Open
Abstract
The mammalian brain is anatomically and functionally complex, and prone to diverse forms of injury and neuropathology. Scientists have long strived to develop cell replacement therapies to repair damaged and diseased nervous tissue. However, this goal has remained unrealized for various reasons, including nascent knowledge of neuronal development, the inability to track and manipulate transplanted cells within complex neuronal networks, and host graft rejection. Recent advances in embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) technology, alongside novel genetic strategies to mark and manipulate stem cell-derived neurons, now provide unprecedented opportunities to investigate complex neuronal circuits in both healthy and diseased brains. Here, we review current technologies aimed at generating and manipulating neurons derived from ESCs and iPSCs toward investigation and manipulation of complex neuronal circuits, ultimately leading to the design and development of novel cell-based therapeutic approaches.
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Affiliation(s)
- Isabella Garcia
- Program in Developmental Biology, Baylor College of Medicine Houston, TX, USA ; Medical Scientist Training Program, Baylor College of Medicine Houston, TX, USA
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14
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Mejía-Toiber J, Limón-Pacheco J, Gonzalez-Gallardo A, Giordano M. In vivo GABA release and kinetics of transgene loss in a GABAergic cell line after long-term transplantation into the rat brain. Neuroscience 2012; 203:244-54. [DOI: 10.1016/j.neuroscience.2011.11.068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 11/08/2011] [Accepted: 11/30/2011] [Indexed: 10/14/2022]
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15
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Weinberg MS, McCown TJ. Current prospects and challenges for epilepsy gene therapy. Exp Neurol 2011; 244:27-35. [PMID: 22008258 DOI: 10.1016/j.expneurol.2011.10.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 09/16/2011] [Accepted: 10/03/2011] [Indexed: 12/25/2022]
Abstract
This review addresses the state of gene therapy research for the treatment of epilepsy. Preclinical studies have demonstrated the anti-seizure efficacy of viral vector-based gene transfer through the use of a variety of strategies - from modulating classic neurotransmitter systems to targeting or overexpressing of neuropeptide receptors in seizure-specific brain regions. While these studies provide substantive proof of principle for viral vector gene therapy, future studies must address the challenges of vector immunity, cellular specificity and effective global delivery. As these issues are resolved, viral vector gene therapy should significantly impact the treatment of intractable epilepsy.
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Affiliation(s)
- Marc S Weinberg
- University of North Carolina Gene Therapy Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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16
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Abstract
Temporal lobe epilepsy (TLE), exemplified by complex partial seizures, is recognized in ~30% of epileptic patients. Seizures in TLE are associated with cognitive dysfunction and are resistant to antiepileptic drug therapy in ~35% of patients. Although surgical resection of the hippocampus bestows improved seizure regulation in most cases of intractable TLE, this choice can cause lasting cognitive deficiency and reliance on antiepileptic drugs. Thus, alternative therapies that are proficient in both containing the spontaneous recurrent seizures and reversing the cognitive dysfunction are needed. The cell transplantation approach is promising in serving as an adept alternate therapy for TLE, because this strategy has shown the capability to curtail epileptogenesis when used soon after an initial precipitating brain injury, and to restrain spontaneous recurrent seizures and improve cognitive function when utilized after the occurrence of TLE. Nonetheless, this treatment needs further advancement and rigorous evaluation in animal prototypes of chronic TLE before the conceivable clinical use. It is especially vital to gauge the efficacy of distinct donor cell types, such as the hippocampal precursor cells, γ-aminobutyric acid-ergic progenitors, and neural stem cells derived from diverse human sources (including the embryonic stem cells and induced pluripotent stem cells) for longstanding seizure suppression using continuous electroencephalographic recordings for prolonged periods. Additionally, the identification of the mechanisms underlying the graft-mediated seizure suppression and improved cognitive function, and the development of apt grafting strategies that enhance the anti-seizure and pro-cognitive effects of grafts will be necessary. The goal of this review is to evaluate the progress made hitherto in this area and to discuss the prospect for cell-based therapy for TLE.
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Affiliation(s)
- Ashok K Shetty
- Institute for Regenerative Medicine, Texas A&M Health Science Center at Scott & White, Department of Molecular and Cellular Medicine, Temple, TX 76502, USA.
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17
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Abstract
Abstract
Neuromodulation strategies have been proposed to treat a variety of neurological disorders, including medication-resistant epilepsy. Electrical stimulation of both central and peripheral nervous systems has emerged as a possible alternative for patients who are not deemed to be good candidates for resective procedures. In addition to well-established treatments such as vagus nerve stimulation, epilepsy centers around the world are investigating the safety and efficacy of neurostimulation at different brain targets, including the hippocampus, thalamus, and subthalamic nucleus. Also promising are the preliminary results of responsive neuromodulation studies, which involve the delivery of stimulation to the brain in response to detected epileptiform or preepileptiform activity. In addition to electrical stimulation, novel therapeutic methods that may open new horizons in the management of epilepsy include transcranial magnetic stimulation, focal drug delivery, cellular transplantation, and gene therapy. We review the current strategies and future applications of neuromodulation in epilepsy.
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Affiliation(s)
- Faisal A Al-Otaibi
- King Faisal Specialist Hospital & Research Centre, Neurosciences Department, Riyadh, Saudi Arabia
| | - Clement Hamani
- Division of Neurosurgery, Toronto Western Hospital, Toronto Western Research Institute, Ontario, Canada
| | - Andres M Lozano
- Division of Neurosurgery, Toronto Western Hospital, Toronto Western Research Institute, Ontario, Canada
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18
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GABAergic neuronal precursor grafting: implications in brain regeneration and plasticity. Neural Plast 2011; 2011:384216. [PMID: 21766042 PMCID: PMC3135013 DOI: 10.1155/2011/384216] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 04/11/2011] [Indexed: 12/20/2022] Open
Abstract
Numerous neurological disorders are caused by a dysfunction of the GABAergic system that impairs or either stimulates its inhibitory action over its neuronal targets. Pharmacological drugs have generally been proved very effective in restoring its normal function, but their lack of any sort of spatial or cell type specificity has created some limitations in their use. In the last decades, cell-based therapies using GABAergic neuronal grafts have emerged as a promising treatment, since they may restore the lost equilibrium by cellular replacement of the missing/altered inhibitory neurons or modulating the hyperactive excitatory system. In particular, the discovery that embryonic ganglionic eminence-derived GABAergic precursors are able to disperse and integrate in large areas of the host tissue after grafting has provided a strong rationale for exploiting their use for the treatment of diseased brains. GABAergic neuronal transplantation not only is efficacious to restore normal GABAergic activities but can also trigger or sustain high neuronal plasticity by promoting the general reorganization of local neuronal circuits adding new synaptic connections. These results cast new light on dynamics and plasticity of adult neuronal assemblies and their associated functions disclosing new therapeutic opportunities for the near future.
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Mejía-Toiber J, Márquez-Ramos JA, Díaz-Muñoz M, Peña F, Aguilar MB, Giordano M. Glutamatergic Excitation and GABA Release from a Transplantable Cell Line. Cell Transplant 2010; 19:1307-23. [DOI: 10.3727/096368910x509059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The cell line M213-2O CL-4 was derived from cell line M213-2O and further modified to express human glutamate decarboxylase (hGAD-67), the enzyme that synthesizes GABA. Brain transplants of this cell line in animal models of epilepsy have been shown to modulate seizures. However, the mechanisms that underlie such actions are unknown. The purpose of the present study was to characterize this cell line and its responsiveness to several depolarizing conditions, in order to better understand how these cells exert their effects. Intracellular GABA levels were 34-fold higher and GAD activity was 16-fold higher in clone M213-2O CL-4 than in M213-2O. Both cell lines could take up [3H]GABA in vitro, and this uptake was prevented by nipecotic acid. By combining GABA release measurements and calcium imaging in vitro, we found that high extracellular K+, zero Mg2+, or glutamate activated M213-2O CL-4 cells and resulted in GABA release. The response to glutamate appeared to be mediated by AMPA/NMDA-like receptors. High KCl-induced GABA release was prevented when a Ca2+-free Krebs solution was used, suggesting an exocytotic-like mechanism. These results indicate that the cell line M213-2O CL-4 synthesizes, releases, and takes up GABA in vitro, and can be activated by depolarizing stimuli.
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Affiliation(s)
- Jana Mejía-Toiber
- Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México
| | | | - Mauricio Díaz-Muñoz
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Quéretaro, México
| | - Fernando Peña
- Departamento de Farmacobiología, CINVESTAV-Sur. Calzada de los Tenorios 235, Delegación Tlalpan, México
| | - Manuel B. Aguilar
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Quéretaro, México
| | - Magda Giordano
- Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México
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20
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Chen X, Wu J, Hua D, Shu K, Wang JZ, Li L, Lei T. The c-Jun N-terminal kinase inhibitor SP600125 is neuroprotective in amygdala kindled rats. Brain Res 2010; 1357:104-14. [PMID: 20692238 DOI: 10.1016/j.brainres.2010.07.082] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2010] [Revised: 07/21/2010] [Accepted: 07/22/2010] [Indexed: 11/25/2022]
Abstract
c-Jun N-terminal kinase (JNK) is implicated in cell death in neurodegenerative disorders and has been taken as a critical point between the physiological and pathological status. JNK specific inhibitor SP600125 has been found to have a protective effect against transient brain ischemia/reperfusion-induced neuronal death in rat hippocampal CA1 region. Former studies have shown the relation between JNK phosphorylation and neuronal damage in models of brain ischemia or in chemically or acute electrically kindled animal in which the stimulus-induced JNK phosphorylation was temporary or transient. In this study, the effect of repeated activation of JNK was examined in the amygdala kindled rats, under or without intraventrical infusion of SP600125, compared with the sham control. JNK phosphorylation was detected by Western blot and immunofluorescent staining in hippocampal extracts and in slices respectively. Nissl staining was performed to detect the neuronal defect. We found that the level of JNK phosphorylation (46KD) in the hippocampus increased in the amygdala kindled rats, whereas such JNK phosphorylation could be inhibited by SP600125. Expression of total JNK in the hippocampus remained unchanged in kindled rats compared with the sham control, and was not affected by SP600125. Neuronal defect was marked in the kindling group and in the vehicle DMSO group, and was alleviated under the administration of SP600125. These findings suggest that JNK phosphorylation is involved in the process of hippocampal sclerosis in the mesial temporal lobe epilepsy (TLE). JNK signaling pathway may be a new target to interfere with the development of hippocampal sclerosis in the temporal lobe epilepsy. The JNK inhibitor SP600125 can show a protective effect on hippocampal neurons in TLE by inhibiting JNK activation.
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Affiliation(s)
- Xu Chen
- Department of Neurosurgery, Tongji Hospital, Huazhong University of Science and Technology, Jiefang Ave 1095, 430030 Wuhan, China
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21
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Castillo CG, Mendoza S, Saavedra J, Giordano M. Lack of effect of intranigral transplants of a GABAergic cell line on absence seizures. Epilepsy Behav 2010; 18:358-65. [PMID: 20634143 DOI: 10.1016/j.yebeh.2010.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 06/03/2010] [Accepted: 06/05/2010] [Indexed: 01/12/2023]
Abstract
The substantia nigra pars reticulata (SNpr) is involved in controlling a variety of seizure phenomena. Intranigral transplants of GABAergic cells have been shown to decrease the severity of already established epileptic seizures, but the effects observed have been short-lived. This study evaluated the ability of intranigral transplants of GABA-producing cells to reduce spontaneous absence seizures in a genetic animal model for periods up to 3 months after transplantation. Intranigral transplants did not induce any behavioral deficits in the animals, and they did not form tumors; however, the transplants failed to decrease absence seizures in the genetic model. The assumed increase in intranigral levels of GABA after the transplants may be insufficient to counteract all the factors involved in generating the absence seizures; in this animal model, it may be necessary to further decrease nigral activity by implanting GABAergic cells in another area. These results bear down on the fact that cell transplants need to be tailored for each type of convulsive disorder in terms of the type of cells delivered and the location of the transplants.
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Affiliation(s)
- Claudia G Castillo
- Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México
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22
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Naegele JR, Maisano X, Yang J, Royston S, Ribeiro E. Recent advancements in stem cell and gene therapies for neurological disorders and intractable epilepsy. Neuropharmacology 2010; 58:855-64. [PMID: 20146928 DOI: 10.1016/j.neuropharm.2010.01.019] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2009] [Revised: 01/22/2010] [Accepted: 01/26/2010] [Indexed: 12/11/2022]
Abstract
The potential applications of stem cell therapies for treating neurological disorders are enormous. Many laboratories are focusing on stem cell treatments for CNS diseases, including spinal cord injury, Amyotrophic lateral sclerosis, Parkinson's disease, Huntington's disease, multiple sclerosis, stroke, traumatic brain injury, and epilepsy. Among the many stem cell types under testing for neurological treatments, the most common are fetal and adult brain stem cells, embryonic stem cells, induced pluripotent stem cells, and mesenchymal stem cells. An expanding toolbox of molecular probes is now available to allow analyses of neural stem cell fates prior to and after transplantation. Concomitantly, protocols are being developed to direct the fates of stem cell-derived neural progenitors, and also to screen stem cells for tumorigenicity and aneuploidy. The rapid progress in the field suggests that novel stem cell and gene therapies for neurological disorders are in the pipeline.
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Affiliation(s)
- Janice R Naegele
- Department of Biology and Program in Neuroscience and Behavior, Hall Atwater Laboratory, 52 Lawn Avenue, Wesleyan University, Middletown, CT 06459, USA.
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Farin A, Liu CY, Langmoen IA, Apuzzo ML. BIOLOGICAL RESTORATION OF CENTRAL NERVOUS SYSTEM ARCHITECTURE AND FUNCTION. Neurosurgery 2009; 65:831-59; discussion 859. [DOI: 10.1227/01.neu.0000351721.81175.0b] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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Barcia JA, Gallego JM. Intraventricular and intracerebral delivery of anti-epileptic drugs in the kindling model. Neurotherapeutics 2009; 6:337-43. [PMID: 19332328 PMCID: PMC5084212 DOI: 10.1016/j.nurt.2009.01.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2008] [Revised: 01/19/2009] [Accepted: 01/22/2009] [Indexed: 11/20/2022] Open
Abstract
A means to avoid the pharmacokinetic problems affecting the anti-epileptic drugs may be their direct intracerebroventricular (ICV) or intracerebral delivery. This approach may achieve a greater drug concentration at the epileptogenic area while minimizing it in other brain or systemic areas, and thus it could be an interesting therapeutic alternative in drug-resistant epilepsies. The objective of this article is to review a series of experiments, ranging from actute ICV injection to continuous intracerebral infusion of anti-epileptic drugs or grafting of neurotransmitter producing cells, in experimental models, especially in the kindling model of epilepsy in the rat. Acute ICV injection of phenytoin, phenobarbital or carbamacepine is able to diminish the intensity of kindling seizures, but it is also associated with a high neurologic toxicity, especially phenobarbital. Continuous ICV infusion of anti-epileptic drugs can effectively control seizures, but neurologic toxicity is not improved compared with systemic delivery. However, systemic toxicity may be improved, as in the case of valproic acid, whose continuous ICV infusion results in very low plasmatic or hepatic drug concentrations. Continuous intracerebral infusion at the epileptogenic area was studied as an alternative to minimize neurologic toxicity. Thus, intra-amygdalar infusion of gamma-aminobutyric acid (GABA) controls seizures with minimal neurotoxicity in amygdala-kindled rats. Similarly, continuous infusion of GABA into the dorsomedian nucleus of the thalamus improves seizure spread, while not affecting the local epileptogenic activity at the amygdala. Grafting of GABA releasing cells may reduce kindling parameter severity without behavioral side effects. We may conclude that ICV or intracerebral delivery of anti-epileptic drugs or neurotransmitters may be a useful technique to modulate epilepsy.
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Affiliation(s)
- Juan A Barcia
- Servicio de Neurocirugía and Instituto de Neurociencias, Hospital Clínico San Carlos, Universidad Complutense de Madrid, 28040 Madrid, Spain.
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Thompson K. Transplantation of GABA-producing cells for seizure control in models of temporal lobe epilepsy. Neurotherapeutics 2009; 6:284-94. [PMID: 19332321 PMCID: PMC5084205 DOI: 10.1016/j.nurt.2009.01.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 01/20/2009] [Accepted: 01/22/2009] [Indexed: 11/27/2022] Open
Abstract
A high percentage of patients with temporal lobe epilepsy (TLE) are refractory to conventional pharmacotherapy. The progressive neurodegenerative processes associated with a lifetime of uncontrolled seizures mandate the development of alternative approaches to treat this disease. Transplantation of inhibitory cells has been suggested as a potential therapeutic strategy to achieve seizure suppression in humans with intractable TLE. Preclinical investigations over 20 years have demonstrated that multiple cell types from several sources can produce anticonvulsant, and antiepileptogenic, effects in animal models of TLE. Transplanting GABA-producing cells, in particular, has been shown to reduce seizures in several well-established models. This review addresses experimentation using different sources of transplantable GABAergic cells, highlighting progress with fetal tissue, neural cell lines, and stem cells. Regardless of the source of the GABAergic cells used in seizure studies, common challenges have emerged. Several variables influence the anticonvulsant potential of GABA-producing cells. For example, tissue availability, graft survival, immunogenicity, tumorigenicity, and varying levels of cell migration, differentiation, and integration into functional circuits and the microenvironment provided by sclerotic tissue all contribute to the efficacy of transplanted cells. The challenge of understanding how all of these variables work in concert, in a disease process that has no well-established etiology, suggests that there is still much basic research to be done before rational cell-based therapies can be developed for TLE.
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Affiliation(s)
- Kerry Thompson
- Department of Biology, Occidental College, Los Angeles, California 90041, USA.
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