1
|
Pastor-Alonso O, Durá I, Bernardo-Castro S, Varea E, Muro-García T, Martín-Suárez S, Encinas-Pérez JM, Pineda JR. HB-EGF activates EGFR to induce reactive neural stem cells in the mouse hippocampus after seizures. Life Sci Alliance 2024; 7:e202201840. [PMID: 38977310 PMCID: PMC11231495 DOI: 10.26508/lsa.202201840] [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: 11/18/2022] [Revised: 06/18/2024] [Accepted: 06/20/2024] [Indexed: 07/10/2024] Open
Abstract
Hippocampal seizures mimicking mesial temporal lobe epilepsy cause a profound disruption of the adult neurogenic niche in mice. Seizures provoke neural stem cells to switch to a reactive phenotype (reactive neural stem cells, React-NSCs) characterized by multibranched hypertrophic morphology, massive activation to enter mitosis, symmetric division, and final differentiation into reactive astrocytes. As a result, neurogenesis is chronically impaired. Here, using a mouse model of mesial temporal lobe epilepsy, we show that the epidermal growth factor receptor (EGFR) signaling pathway is key for the induction of React-NSCs and that its inhibition exerts a beneficial effect on the neurogenic niche. We show that during the initial days after the induction of seizures by a single intrahippocampal injection of kainic acid, a strong release of zinc and heparin-binding epidermal growth factor, both activators of the EGFR signaling pathway in neural stem cells, is produced. Administration of the EGFR inhibitor gefitinib, a chemotherapeutic in clinical phase IV, prevents the induction of React-NSCs and preserves neurogenesis.
Collapse
Affiliation(s)
- Oier Pastor-Alonso
- Laboratory of Neural Stem Cells and Neurogenesis, Achucarro Basque Center for Neuroscience, Bizkaia, Spain
| | - Irene Durá
- Laboratory of Neural Stem Cells and Neurogenesis, Achucarro Basque Center for Neuroscience, Bizkaia, Spain
| | - Sara Bernardo-Castro
- Laboratory of Neural Stem Cells and Neurogenesis, Achucarro Basque Center for Neuroscience, Bizkaia, Spain
| | - Emilio Varea
- Faculty of Biology, University of Valencia, Valencia, Spain
| | - Teresa Muro-García
- Laboratory of Neural Stem Cells and Neurogenesis, Achucarro Basque Center for Neuroscience, Bizkaia, Spain
| | - Soraya Martín-Suárez
- Laboratory of Neural Stem Cells and Neurogenesis, Achucarro Basque Center for Neuroscience, Bizkaia, Spain
| | - Juan Manuel Encinas-Pérez
- Laboratory of Neural Stem Cells and Neurogenesis, Achucarro Basque Center for Neuroscience, Bizkaia, Spain
- Ikerbasque, The Basque Foundation for Science, Bizkaia, Spain
- Department of Neurosciences, University of the Basque Country (UPV/EHU), Bizkaia, Spain
| | - Jose Ramon Pineda
- Laboratory of Neural Stem Cells and Neurogenesis, Achucarro Basque Center for Neuroscience, Bizkaia, Spain
- Signaling Lab, Department of Cell Biology and Histology, Faculty of Medicine and Nursing, University of the Basque Country (UPV/EHU), Bizkaia, Spain
| |
Collapse
|
2
|
Yuan YG, Wang JL, Zhang YX, Li L, Reza AMMT, Gurunathan S. Biogenesis, Composition and Potential Therapeutic Applications of Mesenchymal Stem Cells Derived Exosomes in Various Diseases. Int J Nanomedicine 2023; 18:3177-3210. [PMID: 37337578 PMCID: PMC10276992 DOI: 10.2147/ijn.s407029] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/31/2023] [Indexed: 06/21/2023] Open
Abstract
Exosomes are nanovesicles with a wide range of chemical compositions used in many different applications. Mesenchymal stem cell-derived exosomes (MSCs-EXOs) are spherical vesicles that have been shown to mediate tissue regeneration in a variety of diseases, including neurological, autoimmune and inflammatory, cancer, ischemic heart disease, lung injury, and liver fibrosis. They can modulate the immune response by interacting with immune effector cells due to the presence of anti-inflammatory compounds and are involved in intercellular communication through various types of cargo. MSCs-EXOs exhibit cytokine storm-mitigating properties in response to COVID-19. This review discussed the potential function of MSCs-EXOs in a variety of diseases including neurological, notably epileptic encephalopathy and Parkinson's disease, cancer, angiogenesis, autoimmune and inflammatory diseases. We provided an overview of exosome biogenesis and factors that regulate exosome biogenesis. Additionally, we highlight the functions and potential use of MSCs-EXOs in the treatment of the inflammatory disease COVID-19. Finally, we covered a strategies and challenges of MSCs-EXOs. Finally, we discuss conclusion and future perspectives of MSCs-EXOs.
Collapse
Affiliation(s)
- Yu-Guo Yuan
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People’s Republic of China
- Jiangsu Co-Innovation Center of Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, People’s Republic of China
| | - Jia-Lin Wang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People’s Republic of China
- Jiangsu Co-Innovation Center of Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, People’s Republic of China
| | - Ya-Xin Zhang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People’s Republic of China
- Jiangsu Co-Innovation Center of Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, People’s Republic of China
| | - Ling Li
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People’s Republic of China
- Jiangsu Co-Innovation Center of Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, People’s Republic of China
| | - Abu Musa Md Talimur Reza
- Department of Molecular Biology and Genetics, Faculty of Science, Gebze Technical University, Gebze, Kocaeli, Türkiye
| | | |
Collapse
|
3
|
Upadhya D, Attaluri S, Liu Y, Hattiangady B, Castro OW, Shuai B, Dong Y, Zhang SC, Shetty AK. Grafted hPSC-derived GABA-ergic interneurons regulate seizures and specific cognitive function in temporal lobe epilepsy. NPJ Regen Med 2022; 7:38. [PMID: 35915118 PMCID: PMC9343458 DOI: 10.1038/s41536-022-00234-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 06/24/2022] [Indexed: 11/25/2022] Open
Abstract
Interneuron loss/dysfunction contributes to spontaneous recurrent seizures (SRS) in chronic temporal lobe epilepsy (TLE), and interneuron grafting into the epileptic hippocampus reduces SRS and improves cognitive function. This study investigated whether graft-derived gamma-aminobutyric acid positive (GABA-ergic) interneurons directly regulate SRS and cognitive function in a rat model of chronic TLE. Human pluripotent stem cell-derived medial ganglionic eminence-like GABA-ergic progenitors, engineered to express hM4D(Gi), a designer receptor exclusively activated by designer drugs (DREADDs) through CRISPR/Cas9 technology, were grafted into hippocampi of chronically epileptic rats to facilitate the subsequent silencing of graft-derived interneurons. Such grafting substantially reduced SRS and improved hippocampus-dependent cognitive function. Remarkably, silencing of graft-derived interneurons with a designer drug increased SRS and induced location memory impairment but did not affect pattern separation function. Deactivation of DREADDs restored both SRS control and object location memory function. Thus, transplanted GABA-ergic interneurons could directly regulate SRS and specific cognitive functions in TLE.
Collapse
Affiliation(s)
- Dinesh Upadhya
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA.,Centre for Molecular Neurosciences, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Sahithi Attaluri
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA
| | - Yan Liu
- Waisman Center, Departments of Neuroscience and Neurology, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Bharathi Hattiangady
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA
| | - Olagide W Castro
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA.,Institute of Biological Sciences and Health, Federal Univ of Alagoas (UFAL), Maceio, AL, Brazil
| | - Bing Shuai
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA.,Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA
| | - Yi Dong
- Waisman Center, Departments of Neuroscience and Neurology, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Su-Chun Zhang
- Waisman Center, Departments of Neuroscience and Neurology, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Ashok K Shetty
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA. .,Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA. .,Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA.
| |
Collapse
|
4
|
Upadhya D, Shetty AK. Promise of extracellular vesicles for diagnosis and treatment of epilepsy. Epilepsy Behav 2021; 121:106499. [PMID: 31636006 PMCID: PMC7165061 DOI: 10.1016/j.yebeh.2019.106499] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/13/2019] [Accepted: 08/14/2019] [Indexed: 01/08/2023]
Abstract
Extracellular vesicles (EVs) released from cells play vital roles in intercellular communication. Moreover, EVs released from stem cells have therapeutic properties. This review confers the potential of brain-derived EVs in the cerebrospinal fluid (CSF) and the serum as sources of epilepsy-related biomarkers, and the promise of mesenchymal stem cell (MSC)-derived EVs for easing status epilepticus (SE)-induced adverse changes in the brain. Extracellular vesicles shed from neurons and glia in the brain can also be found in the circulating blood as EVs cross the blood-brain barrier (BBB). Evaluation of neuron and/or glia-derived EVs in the blood of patients who have epilepsy could help in identifying specific biomarkers for distinct types of epilepsies. Such a liquid biopsy approach is also amenable for repeated analysis in clinical trials for comprehending treatment efficacy, disease progression, and mechanisms of therapeutic interventions. Extracellular vesicle biomarker studies in animal prototypes of epilepsy, in addition, could help in identifying specific micro ribonucleic acid (miRNAs) contributing to epileptogenesis, seizures, or cognitive dysfunction in different types of epilepsy. Furthermore, intranasal (IN) administration of MSC-derived EVs after SE has shown efficacy for restraining SE-induced neuroinflammation, aberrant neurogenesis, and cognitive dysfunction in an animal prototype. Clinical translation of EV therapy as an adjunct to antiepileptic drugs appears attractive to counteract the progression of SE-induced epileptogenic changes, as the risk for thrombosis or tumor is minimal with nanosized EVs. Also, EVs can be engineered to deliver specific miRNAs, proteins, or antiepileptic drugs to the brain since they incorporate into neurons and glia throughout the brain after IN administration. This article is part of the Special Issue "NEWroscience 2018".
Collapse
Affiliation(s)
- Dinesh Upadhya
- Centre for Molecular Neurosciences, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Ashok K. Shetty
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, Texas, USA
| |
Collapse
|
5
|
Hattiangady B, Kuruba R, Shuai B, Grier R, Shetty AK. Hippocampal Neural Stem Cell Grafting after Status Epilepticus Alleviates Chronic Epilepsy and Abnormal Plasticity, and Maintains Better Memory and Mood Function. Aging Dis 2020; 11:1374-1394. [PMID: 33269095 PMCID: PMC7673840 DOI: 10.14336/ad.2020.1020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 10/20/2020] [Indexed: 12/11/2022] Open
Abstract
Hippocampal damage after status epilepticus (SE) leads to multiple epileptogenic changes, which lead to chronic temporal lobe epilepsy (TLE). Morbidities such as spontaneous recurrent seizures (SRS) and memory and mood impairments are seen in a significant fraction of SE survivors despite the administration of antiepileptic drugs after SE. We examined the efficacy of bilateral intra-hippocampal grafting of neural stem/progenitor cells (NSCs) derived from the embryonic day 19 rat hippocampi, six days after SE for restraining SE-induced SRS, memory, and mood impairments in the chronic phase. Grafting of NSCs curtailed the progression of SRS at 3-5 months post-SE and reduced the frequency and severity of SRS activity when examined at eight months post-SE. Reduced SRS activity was also associated with improved memory function. Graft-derived cells migrated into different hippocampal cell layers, differentiated into GABA-ergic interneurons, astrocytes, and oligodendrocytes. Significant percentages of graft-derived cells also expressed beneficial neurotrophic factors such as the fibroblast growth factor-2, brain-derived neurotrophic factor, insulin-like growth factor-1 and glial cell line-derived neurotrophic factor. NSC grafting protected neuropeptide Y- and parvalbumin-positive host interneurons, diminished the abnormal migration of newly born neurons, and rescued the reelin+ interneurons in the dentate gyrus. Besides, grafting led to the maintenance of a higher level of normal neurogenesis in the chronic phase after SE and diminished aberrant mossy fiber sprouting in the dentate gyrus. Thus, intrahippocampal grafting of hippocampal NSCs shortly after SE considerably curbed the progression of epileptogenic processes and SRS, which eventually resulted in less severe chronic epilepsy devoid of significant cognitive and mood impairments.
Collapse
Affiliation(s)
- Bharathi Hattiangady
- 1Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA.,2Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA.,3Department of Surgery (Neurosurgery) Duke University Medical Center, Durham, NC, USA.,4Research and Surgery Services, Durham Veterans Affairs Medical Center, Durham, NC, USA
| | - Ramkumar Kuruba
- 3Department of Surgery (Neurosurgery) Duke University Medical Center, Durham, NC, USA.,4Research and Surgery Services, Durham Veterans Affairs Medical Center, Durham, NC, USA
| | - Bing Shuai
- 1Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA.,2Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA.,3Department of Surgery (Neurosurgery) Duke University Medical Center, Durham, NC, USA.,4Research and Surgery Services, Durham Veterans Affairs Medical Center, Durham, NC, USA
| | - Remedios Grier
- 3Department of Surgery (Neurosurgery) Duke University Medical Center, Durham, NC, USA.,4Research and Surgery Services, Durham Veterans Affairs Medical Center, Durham, NC, USA
| | - Ashok K Shetty
- 1Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA.,2Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, TX, USA.,3Department of Surgery (Neurosurgery) Duke University Medical Center, Durham, NC, USA.,4Research and Surgery Services, Durham Veterans Affairs Medical Center, Durham, NC, USA
| |
Collapse
|
6
|
Extracellular Vesicles in the Forebrain Display Reduced miR-346 and miR-331-3p in a Rat Model of Chronic Temporal Lobe Epilepsy. Mol Neurobiol 2019; 57:1674-1687. [PMID: 31813125 DOI: 10.1007/s12035-019-01797-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 09/22/2019] [Indexed: 12/20/2022]
Abstract
An initial precipitating injury in the brain, such as after status epilepticus (SE), evolves into chronic temporal lobe epilepsy (TLE). We investigated changes in the miRNA composition of extracellular vesicles (EVs) in the forebrain after the establishment of SE-induced chronic TLE. We induced SE in young Fischer 344 rats through graded intraperitoneal injections of kainic acid, which resulted in consistent spontaneous recurrent seizures at ~ 3 months post-SE. We isolated EVs from the entire forebrain of chronically epileptic rats and age-matched naïve control animals through an ultracentrifugation method and performed miRNA-sequencing studies to discern changes in the miRNA composition of forebrain-derived EVs in chronic epilepsy. EVs from both naïve and epileptic forebrains displayed spherical or cup-shaped morphology, a comparable size range, and CD63 expression but lacked the expression of a deep cellular marker GM130. However, miRNA-sequencing studies suggested downregulation of 3 miRNAs (miR-187-5p, miR-346, and miR-331-3p) and upregulation of 4 miRNAs (miR-490-5p, miR-376b-3p, miR-493-5p, and miR-124-5p) in EVs from epileptic forebrains with fold changes ranging from 1.5 to 2.4 (p < 0.0006; FDR < 0.05). By using geNorm and Normfinder software, we identified miR-487 and miR-221 as the best combination of reference genes for measurement of altered miRNAs found in the epileptic forebrain through qRT-PCR studies. The validation revealed that only miR-346 and miR-331-3p were significantly downregulated in EVs from the epileptic forebrain. The enrichment pathway analysis of these miRNAs showed an overrepresentation of signaling pathways that are linked to molecular mechanisms underlying chronic epilepsy, including GABA-ergic (miR-346 targets) and mTOR (miR-331-3p targets) systems. Thus, the packaging of two miRNAs into EVs in neural cells is considerably altered in chronic epilepsy. Functional studies on these two miRNAs may uncover their role in the pathophysiology and treatment of TLE.
Collapse
|
7
|
Mateus JM, Ribeiro FF, Alonso-Gomes M, Rodrigues RS, Marques JM, Sebastião AM, Rodrigues RJ, Xapelli S. Neurogenesis and Gliogenesis: Relevance of Adenosine for Neuroregeneration in Brain Disorders. J Caffeine Adenosine Res 2019. [DOI: 10.1089/caff.2019.0010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Joana M. Mateus
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Filipa F. Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Marta Alonso-Gomes
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Rui S. Rodrigues
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Joana M. Marques
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Ana M. Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Ricardo J. Rodrigues
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Sara Xapelli
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| |
Collapse
|
8
|
Leite Góes Gitai D, de Andrade TG, Dos Santos YDR, Attaluri S, Shetty AK. Chronobiology of limbic seizures: Potential mechanisms and prospects of chronotherapy for mesial temporal lobe epilepsy. Neurosci Biobehav Rev 2019; 98:122-134. [PMID: 30629979 PMCID: PMC7023906 DOI: 10.1016/j.neubiorev.2019.01.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 12/20/2018] [Accepted: 01/06/2019] [Indexed: 12/11/2022]
Abstract
Mesial Temporal Lobe Epilepsy (mTLE) characterized by progressive development of complex partial seizures originating from the hippocampus is the most prevalent and refractory type of epilepsy. One of the remarkable features of mTLE is the rhythmic pattern of occurrence of spontaneous seizures, implying a dependence on the endogenous clock system for seizure threshold. Conversely, circadian rhythms are affected by epilepsy too. Comprehending how the circadian system and seizures interact with each other is essential for understanding the pathophysiology of epilepsy as well as for developing innovative therapies that are efficacious for better seizure control. In this review, we confer how the temporal dysregulation of the circadian clock in the hippocampus combined with multiple uncoupled oscillators could lead to periodic seizure occurrences and comorbidities. Unraveling these associations with additional research would help in developing chronotherapy for mTLE, based on the chronobiology of spontaneous seizures. Notably, differential dosing of antiepileptic drugs over the circadian period and/or strategies that resynchronize biological rhythms may substantially improve the management of seizures in mTLE patients.
Collapse
Affiliation(s)
- Daniel Leite Góes Gitai
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University, College Station, Texas, USA; Institute of Biological Sciences and Health, Federal University of Alagoas, Maceio, Alagoas, Brazil
| | | | | | - Sahithi Attaluri
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University, College Station, Texas, USA
| | - Ashok K Shetty
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University, College Station, Texas, USA; Research Service, Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, Texas, USA.
| |
Collapse
|
9
|
Koyama R, Ikegaya Y. The Molecular and Cellular Mechanisms of Axon Guidance in Mossy Fiber Sprouting. Front Neurol 2018; 9:382. [PMID: 29896153 PMCID: PMC5986954 DOI: 10.3389/fneur.2018.00382] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 05/11/2018] [Indexed: 01/25/2023] Open
Abstract
The question of whether mossy fiber sprouting is epileptogenic has not been resolved; both sprouting-induced recurrent excitatory and inhibitory circuit hypotheses have been experimentally (but not fully) supported. Therefore, whether mossy fiber sprouting is a potential therapeutic target for epilepsy remains under debate. Moreover, the axon guidance mechanisms of mossy fiber sprouting have attracted the interest of neuroscientists. Sprouting of mossy fibers exhibits several uncommon axonal growth features in the basically non-plastic adult brain. For example, robust branching of axonal collaterals arises from pre-existing primary mossy fiber axons. Understanding the branching mechanisms in adulthood may contribute to axonal regeneration therapies in neuroregenerative medicine in which robust axonal re-growth is essential. Additionally, because granule cells are produced throughout life in the neurogenic dentate gyrus, it is interesting to examine whether the mossy fibers of newly generated granule cells follow the pre-existing trajectories of sprouted mossy fibers in the epileptic brain. Understanding these axon guidance mechanisms may contribute to neuron transplantation therapies, for which the incorporation of transplanted neurons into pre-existing neural circuits is essential. Thus, clarifying the axon guidance mechanisms of mossy fiber sprouting could lead to an understanding of central nervous system (CNS) network reorganization and plasticity. Here, we review the molecular and cellular mechanisms of axon guidance in mossy fiber sprouting by discussing mainly in vitro studies.
Collapse
Affiliation(s)
- Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
10
|
Prospects of Cannabidiol for Easing Status Epilepticus-Induced Epileptogenesis and Related Comorbidities. Mol Neurobiol 2018; 55:6956-6964. [PMID: 29372545 DOI: 10.1007/s12035-018-0898-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 01/09/2018] [Indexed: 12/21/2022]
Abstract
The hippocampus is one of the most susceptible regions in the brain to be distraught with status epilepticus (SE) induced injury. SE can occur from numerous causes and is more frequent in children and the elderly population. Administration of a combination of antiepileptic drugs can abolish acute seizures in most instances of SE but cannot prevent the morbidity typically seen in survivors of SE such as cognitive and mood impairments and spontaneous recurrent seizures. This is primarily due to the inefficiency of antiepileptic drugs to modify the evolution of SE-induced initial precipitating injury into a series of epileptogenic changes followed by a state of chronic epilepsy. Chronic epilepsy is typified by spontaneous recurrent seizures, cognitive dysfunction, and depression, which are associated with persistent inflammation, significantly waned neurogenesis, and abnormal synaptic reorganization. Thus, alternative approaches that are efficient not only for curtailing SE-induced initial brain injury, neuroinflammation, aberrant neurogenesis, and abnormal synaptic reorganization but also for thwarting or restraining the progression of SE into a chronic epileptic state are needed. In this review, we confer the promise of cannabidiol, an active ingredient of Cannabis sativa, for preventing or easing SE-induced neurodegeneration, neuroinflammation, cognitive and mood impairments, and the spontaneous recurrent seizures.
Collapse
|
11
|
Navidhamidi M, Ghasemi M, Mehranfard N. Epilepsy-associated alterations in hippocampal excitability. Rev Neurosci 2018; 28:307-334. [PMID: 28099137 DOI: 10.1515/revneuro-2016-0059] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 11/03/2016] [Indexed: 11/15/2022]
Abstract
The hippocampus exhibits a wide range of epilepsy-related abnormalities and is situated in the mesial temporal lobe, where limbic seizures begin. These abnormalities could affect membrane excitability and lead to overstimulation of neurons. Multiple overlapping processes refer to neural homeostatic responses develop in neurons that work together to restore neuronal firing rates to control levels. Nevertheless, homeostatic mechanisms are unable to restore normal neuronal excitability, and the epileptic hippocampus becomes hyperexcitable or hypoexcitable. Studies show that there is hyperexcitability even before starting recurrent spontaneous seizures, suggesting although hippocampal hyperexcitability may contribute to epileptogenesis, it alone is insufficient to produce epileptic seizures. This supports the concept that the hippocampus is not the only substrate for limbic seizure onset, and a broader hyperexcitable limbic structure may contribute to temporal lobe epilepsy (TLE) seizures. Nevertheless, seizures also occur in conditions where the hippocampus shows a hypoexcitable phenotype. Since TLE seizures most often originate in the hippocampus, it could therefore be assumed that both hippocampal hypoexcitability and hyperexcitability are undesirable states that make the epileptic hippocampal network less stable and may, under certain conditions, trigger seizures.
Collapse
|
12
|
Castro OW, Upadhya D, Kodali M, Shetty AK. Resveratrol for Easing Status Epilepticus Induced Brain Injury, Inflammation, Epileptogenesis, and Cognitive and Memory Dysfunction-Are We There Yet? Front Neurol 2017; 8:603. [PMID: 29180982 PMCID: PMC5694141 DOI: 10.3389/fneur.2017.00603] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 10/30/2017] [Indexed: 12/29/2022] Open
Abstract
Status epilepticus (SE) is a medical emergency exemplified by self-sustaining, unceasing seizures or swiftly recurring seizure events with no recovery between seizures. The early phase after SE event is associated with neurodegeneration, neuroinflammation, and abnormal neurogenesis in the hippocampus though the extent of these changes depends on the severity and duration of seizures. In many instances, over a period, the initial precipitating injury caused by SE leads to temporal lobe epilepsy (TLE), typified by spontaneous recurrent seizures, cognitive, memory and mood impairments associated with chronic inflammation, reduced neurogenesis, abnormal synaptic reorganization, and multiple molecular changes in the hippocampus. While antiepileptic drugs are efficacious for terminating or greatly reducing seizures in most cases of SE, they have proved ineffective for easing SE-induced epileptogenesis and TLE. Despite considerable advances in elucidating SE-induced multiple cellular, electrophysiological, and molecular changes in the brain, efficient strategies that prevent SE-induced TLE development are yet to be discovered. This review critically confers the efficacy and promise of resveratrol, a phytoalexin found in the skin of red grapes, for easing SE-induced neurodegeneration, neuroinflammation, aberrant neurogenesis, and for restraining the evolution of SE-induced brain injury into a chronic epileptic state typified by spontaneous recurrent seizures, and learning, memory, and mood impairments.
Collapse
Affiliation(s)
- Olagide W Castro
- Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, Texas, United States.,Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, Texas, United States.,Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Maceio, Brazil
| | - Dinesh Upadhya
- Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, Texas, United States.,Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, Texas, United States.,Department of Anatomy, Kasturba Medical College, Manipal University, Manipal, India
| | - Maheedhar Kodali
- Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, Texas, United States.,Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, Texas, United States
| | - Ashok K Shetty
- Olin E. Teague Veterans' Medical Center, Central Texas Veterans Health Care System, Temple, Texas, United States.,Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, Texas, United States
| |
Collapse
|
13
|
Vrinda M, Sasidharan A, Aparna S, Srikumar BN, Kutty BM, Shankaranarayana Rao BS. Enriched environment attenuates behavioral seizures and depression in chronic temporal lobe epilepsy. Epilepsia 2017; 58:1148-1158. [PMID: 28480502 DOI: 10.1111/epi.13767] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/27/2017] [Indexed: 01/30/2023]
Abstract
OBJECTIVE Temporal lobe epilepsy (TLE) is commonly associated with depression, anxiety, and cognitive impairment. Despite significant progress in our understanding of the pathophysiology of TLE, it remains the most common form of refractory epilepsy. Enriched environment (EE) has a beneficial effect in many neuropsychiatric disorders. However, the effect of EE on cognitive changes in chronic TLE has not been evaluated. Accordingly, the present study evaluated the effects of EE on chronic epilepsy-induced alterations in cognitive functions, electrophysiology, and cellular changes in the hippocampus. METHODS Status epilepticus (SE) was induced in 2-month-old male Wistar rats with lithium and pilocarpine. Six weeks' post SE, epileptic rats were either housed in their respective home cages or in an enrichment cage (6 h/day) for 14 days. Seizure behavior was video-monitored 2 weeks before and during exposure to EE. Depression-like behavior, anxiety-like behavior, and spatial learning and memory were assessed using the sucrose preference test (SPT), elevated plus maze (EPM), and Morris water maze (MWM), respectively. Delta and theta power in the CA1 region of hippocampus was assessed from recordings of local field potentials (LFPs). Cellular changes in hippocampus were assessed by histochemistry followed by unbiased stereologic analysis. RESULTS EE significantly reduced seizure episodes and seizure duration in epileptic rats. In addition, EE alleviated depression and hyperactivity, and restored delta and theta power of LFP in the hippocampal CA1 region. However, EE neither ameliorated epilepsy-induced spatial learning and memory deficits nor restored cell density in hippocampus. SIGNIFICANCE This is the first study that evaluates the role of EE in a chronic TLE model, where rats were exposed to EE after occurrence of spontaneous recurrent seizures (SRS). Given that 30% of TLE patients are refractory to drug treatment, therapeutic strategies that utilize components of EE could be designed to alleviate seizures and psychiatric comorbidities associated with TLE.
Collapse
Affiliation(s)
- Marigowda Vrinda
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bengaluru, India.,Axxonet Brain Research Laboratory, Axxonet System Technologies Pvt. Ltd., Bengaluru, 560 029, India
| | - Arun Sasidharan
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bengaluru, India.,Axxonet Brain Research Laboratory, Axxonet System Technologies Pvt. Ltd., Bengaluru, 560 029, India
| | - Sahajan Aparna
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bengaluru, India
| | - Bettadapura N Srikumar
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bengaluru, India
| | - Bindu M Kutty
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bengaluru, India
| | | |
Collapse
|
14
|
Raghu KS, Shamprasad BR, Kabekkodu SP, Paladhi P, Joshi MB, Valiathan MS, Guruprasad KP, Satyamoorthy K. Age dependent neuroprotective effects of medhya rasayana prepared from Clitoria ternatea Linn. in stress induced rat brain. JOURNAL OF ETHNOPHARMACOLOGY 2017; 197:173-183. [PMID: 27469198 DOI: 10.1016/j.jep.2016.07.068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 07/16/2016] [Accepted: 07/25/2016] [Indexed: 05/28/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Indian traditional medicinal system in Ayurveda suggests several preparations, known as medhya rasayanas, of diverse plant origin to enhance the health in general, reduce stress and improve brain function in particular during ageing. These effects in the context of contemporary knowledge and the underlying mechanisms are not clearly understood. Autophagy and DNA damage induced repair are inter-related quintessential pathways and are significantly altered during stress and ageing. Hence, medhya rasayana prepared from Clitoria ternatea (locally known as shankhpushpi) was used to test these effects in Wistar rat model of various age groups upon stereotaxic mediated kainic acid induced brain injury. MATERIALS AND METHODS The rodent experiments were carried out in one, twelve and eighteen months old male Wistar rats. The rats were orally fed with medhya rasayana prepared from Clitoria ternatea (3g per kg body weight/day) for 60 days. Stereotaxic mediated kainate stress to the hippocampus was performed on day 61. The rats were sacrificed on 66th day and the brain tissues were analyzed histologically and measured for autophagy, base excision repair and antioxidant enzyme activities. In addition, cognitive functions were analyzed by employing novel object recognition task and Morris water maze tests. The gene expression profile of hippocampus was assessed by microarray hybridization and two genes are validated. RESULTS Our study showed significant decrease of autophagy by medhya rasayana in both 12 and 18 months old rats. The hippocampal CA3 cellularity were increased in stereotaxic mediated stressed rats by medhya rasayana. There were no significant differences in constitutive base excision repair and antioxidant enzyme activities. Medhya rasayana treatment also significantly increased episodic memory in rats. Microarray experiments for pathway specific gene expression analysis showed altered expression of genes of long-term potentiation, axon guidance, neuroactive ligand-receptor interaction, regulation of autophagy, lysosome, homologous recombination and nucleotide excision repair pathways in adult rats by medhya rasayana. CONCLUSIONS In the present study, we show that reduction in autophagy is crucial for medhya rasayana induced protection of rat hippocampal cells and that artificially enhanced autophagy protects the brain cell damage by maintaining the selective DNA damage repair pathway and removal of reactive oxygen species to inhibit apoptosis. These findings suggest autophagy directed pathways by medhya rasayana prepared from C. ternatea protects the brain cells from stress induced injury.
Collapse
Affiliation(s)
- Kothanahalli S Raghu
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal 576 104, Karnataka, India.
| | - Bhanuvalli R Shamprasad
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal 576 104, Karnataka, India.
| | - Shama P Kabekkodu
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal 576 104, Karnataka, India.
| | - Puspendu Paladhi
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal 576 104, Karnataka, India.
| | - Manjunath B Joshi
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal 576 104, Karnataka, India.
| | | | - Kanive P Guruprasad
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal 576 104, Karnataka, India.
| | - Kapaettu Satyamoorthy
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal 576 104, Karnataka, India.
| |
Collapse
|
15
|
Puttachary S, Sharma S, Verma S, Yang Y, Putra M, Thippeswamy A, Luo D, Thippeswamy T. 1400W, a highly selective inducible nitric oxide synthase inhibitor is a potential disease modifier in the rat kainate model of temporal lobe epilepsy. Neurobiol Dis 2016; 93:184-200. [PMID: 27208748 DOI: 10.1016/j.nbd.2016.05.013] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 05/04/2016] [Accepted: 05/15/2016] [Indexed: 12/21/2022] Open
Abstract
Status epilepticus (SE) initiates epileptogenesis to transform normal brain to epileptic state which is characterized by spontaneous recurrent seizures (SRS). Prior to SRS, progressive changes occur in the brain soon after SE, for example, loss of blood-brain barrier (BBB) integrity, neuronal hyper-excitability (epileptiform spiking), neuroinflammation [reactive gliosis, high levels of reactive oxygen/nitrogen species (ROS/RNS)], neurodegeneration and synaptic re-organization. Our hypothesis was that modification of early epileptogenic events will alter the course of disease development and its progression. We tested the hypothesis in the rat kainate model of chronic epilepsy using a novel disease modifying drug, 1400W, a highly selective inhibitor of inducible nitric oxide synthase (iNOS/NOS-II). In an in vitro mouse brain slice model, using a multi-electrode array system, co-application of 1400W with kainate significantly suppressed kainate-induced epileptiform spiking. In the rats, in vivo, 4h after the induction of SE with kainate, 1400W (20mg/kg, i.p.) was administered twice daily for three days to target early events of epileptogenesis. The rats were subjected to continuous (24/7) video-EEG monitoring, remotely, for six months from epidurally implanted cortical electrodes. The 1400W treatment significantly reduced the epileptiform spike rate during the first 12-74h post-SE, which resulted in >90% reduction in SRS in long-term during the six month period when compared to the vehicle-treated control group (257±113 versus 19±10 episodes). Immunohistochemistry (IHC) of brain sections at seven days and six months revealed a significant reduction in; reactive astrogliosis and microgliosis (M1 type), extravascular serum albumin (a marker for BBB leakage) and neurodegeneration in the hippocampus, amygdala and entorhinal cortex in the 1400W-treated rats when compared to the vehicle control. In the seven day group, hippocampal Western blots revealed downregulation of inwardly-rectifying potassium (Kir 4.1) channels and glutamate transporter-1 (GLT-1) levels in the vehicle group, and 1400W treatment partially reversed Kir 4.1 levels, however, GLT-1 levels were unaffected. In the six month group, a significant reduction in mossy fiber staining intensity in the inner molecular layer of the dentate gyrus was observed in the 1400W-treated group. Overall these findings demonstrate that 1400W, by reducing the epileptiform spike rate during the first three days of post-insult, potentially modifies epileptogenesis and the severity of chronic epilepsy in the rat kainate model of TLE.
Collapse
Affiliation(s)
- Sreekanth Puttachary
- Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50010, USA
| | - Shaunik Sharma
- Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50010, USA
| | - Saurabh Verma
- Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50010, USA
| | - Yang Yang
- Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50010, USA
| | - Marson Putra
- Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50010, USA
| | - Achala Thippeswamy
- Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50010, USA
| | - Diou Luo
- Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50010, USA
| | | |
Collapse
|
16
|
Wang Q, Hong P, Gao H, Chen Y, Yang Q, Jiang M, Li H. An interneuron progenitor maintains neurogenic potential in vivo and differentiates into GABAergic interneurons after transplantation in the postnatal rat brain. Sci Rep 2016; 6:19003. [PMID: 26750620 PMCID: PMC4707470 DOI: 10.1038/srep19003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 11/27/2015] [Indexed: 02/05/2023] Open
Abstract
Dysfunction of cortical GABAergic interneurons are involved in numerous neurological disorders including epilepsy, schizophrenia and autism; and replenishment of these cells by transplantation strategy has proven to be a feasible and effective method to help revert the symptoms in several animal models. To develop methodology of generating transplantable GABAergic interneurons for therapy, we previously reported the isolation of a v-myc-induced GABAergic interneuron progenitor clone GE6 from embryonic ganglionic eminence (GE). These cells can proliferate and form functional inhibitory synapses in culture. Here, we tested their differentiation behavior in vivo by transplanting them into the postnatal rat forebrain. We found that GE6 cells migrate extensively in the neonatal forebrain and differentiate into both neurons and glia, but preferentially into neurons when compared with a sister progenitor clone CTX8. The neurogenic potential of GE6 cells is also maintained after transplantation into a non-permissive environment such as adult cortex or when treated with inflammatory cytokine in culture. The GE6-derived neurons were able to mature in vivo as GABAergic interneurons expressing GABAergic, not glutamatergic, presynaptic puncta. Finally, we propose that v-myc-induced human interneuron progenitor clones could be an alternative cell source of transplantable GABAergic interneurons for treating related neurological diseases in future clinic.
Collapse
Affiliation(s)
- Qi Wang
- West China Developmental &Stem Cell Institute, Department of Obstetric &Gynecologic and Pediatric, Key Laboratory of Obstetric &Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu 610041, P.R. China
| | - Peiwei Hong
- Department of Neurology, West China Hospital, Sichuan University, Chengdu 610041, P.R. China
| | - Hui Gao
- Department of Neurology, West China Hospital, Sichuan University, Chengdu 610041, P.R. China
| | - Yuntian Chen
- Department of Urology, West China Hospital, Sichuan University, Chengdu 610041, P.R. China
| | - Qi Yang
- West China Developmental &Stem Cell Institute, Department of Obstetric &Gynecologic and Pediatric, Key Laboratory of Obstetric &Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu 610041, P.R. China
| | - Mei Jiang
- West China Developmental &Stem Cell Institute, Department of Obstetric &Gynecologic and Pediatric, Key Laboratory of Obstetric &Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu 610041, P.R. China
| | - Hedong Li
- West China Developmental &Stem Cell Institute, Department of Obstetric &Gynecologic and Pediatric, Key Laboratory of Obstetric &Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu 610041, P.R. China
| |
Collapse
|
17
|
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: 63] [Impact Index Per Article: 6.3] [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.
Collapse
|
18
|
Learning-induced synaptic potentiation in implanted neural precursor cell-derived neurons. Sci Rep 2015; 5:17796. [PMID: 26634434 PMCID: PMC4669478 DOI: 10.1038/srep17796] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 11/05/2015] [Indexed: 12/17/2022] Open
Abstract
Neuronal loss caused by neurodegenerative diseases, traumatic brain injury and stroke results in cognitive dysfunctioning. Implantation of neural stem/precursor cells (NPCs) can improve the brain function by replacing lost neurons. Proper synaptic integration following neuronal differentiation of implanted cells is believed to be a prerequisite for the functional recovery. In the present study, we characterized the functional properties of immortalized neural progenitor HiB5 cells implanted into the rat hippocampus with chemically induced lesion. The implanted HiB5 cells migrated toward CA1 pyramidal layer and differentiated into vGluT1-positive glutamatergic neurons with morphological and electrophysiological properties of endogenous CA1 pyramidal cells. Functional synaptic integration of HiB5 cell-derived neurons was also evidenced by immunohistochemical and electrophysiological data. Lesion-caused memory deficit was significantly recovered after the implantation when assessed by inhibitory avoidance (IA) learning. Remarkably, IA learning preferentially produced long-term potentiation (LTP) at the synapses onto HiB5 cell-derived neurons, which occluded paring protocol-induced LTP ex vivo. We conclude that the implanted HiB5 cell-derived neurons actively participate in learning process through LTP formation, thereby counteracting lesion-mediated memory impairment.
Collapse
|
19
|
Kourdougli N, Varpula S, Chazal G, Rivera C. Detrimental effect of post Status Epilepticus treatment with ROCK inhibitor Y-27632 in a pilocarpine model of temporal lobe epilepsy. Front Cell Neurosci 2015; 9:413. [PMID: 26557054 PMCID: PMC4615811 DOI: 10.3389/fncel.2015.00413] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Accepted: 09/28/2015] [Indexed: 01/18/2023] Open
Abstract
Temporal lobe epilepsy (TLE) is the most common type of epilepsy in adults where 20-30% of the patients are refractory to currently available anti-epileptic drugs. The RhoA/Rho-kinase signaling pathway activation has been involved in inflammatory responses, neurite outgrowth and neuronal death under pathological conditions such as epileptic insults. Acute preventive administration of ROCK inhibitor has been reported to have beneficial outcomes in Status Epilepticus (SE) epilepsy. In the present study, we evaluate the effect of chronic post SE treatment with the ROCK inhibitor Y-27632 in a rat pilocarpine model of TLE. We used chronic i.p. injections of Y-27632 for 5 days in 6 week old control rats or rats subjected to pilocarpine treatment as a model of TLE. Surprisingly, our findings demonstrate that a systemic administration of Y-27632 in pilocarpine-treated rats increases neuronal death in the CA3 region and ectopic recurrent mossy fiber sprouting (rMFS) in the dentate gyrus of the hippocampal formation. Interestingly, we found that chronic treatment with Y-27632 exacerbates the down-regulation and pathological distribution of the K(+)-Cl(-) cotransporter KCC2, thus providing a putative mechanism for post SE induced neuronal death. The involvement of astrogliosis in this mechanism appears to be intricate as ROCK inhibition reduces reactive astrogliosis in pilocarpine rats. Conversely, in control rats, chronic Y-27632 treatment increases astrogliosis. Together, our findings suggest that Y-27632 has a detrimental effect when chronically used post SE in a rat pilocarpine model of TLE.
Collapse
Affiliation(s)
- Nazim Kourdougli
- INSERM Unité 901, INMEDMarseille, France
- Aix-Marseille Université, UMR S901Marseille, France
| | - Saara Varpula
- INSERM Unité 901, INMEDMarseille, France
- Aix-Marseille Université, UMR S901Marseille, France
- Neuroscience Center, University of HelsinkiHelsinki, Finland
| | - Genevieve Chazal
- INSERM Unité 901, INMEDMarseille, France
- Aix-Marseille Université, UMR S901Marseille, France
| | - Claudio Rivera
- INSERM Unité 901, INMEDMarseille, France
- Aix-Marseille Université, UMR S901Marseille, France
- Neuroscience Center, University of HelsinkiHelsinki, Finland
| |
Collapse
|
20
|
Agadi S, Shetty AK. Concise Review: Prospects of Bone Marrow Mononuclear Cells and Mesenchymal Stem Cells for Treating Status Epilepticus and Chronic Epilepsy. Stem Cells 2015; 33:2093-103. [PMID: 25851047 DOI: 10.1002/stem.2029] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 03/16/2015] [Indexed: 12/22/2022]
Abstract
Mononuclear cells (MNCs) and mesenchymal stem cells (MSCs) derived from the bone marrow and other sources have received significant attention as donor cells for treating various neurological disorders due to their robust neuroprotective and anti-inflammatory effects. Moreover, it is relatively easy to procure these cells from both autogenic and allogenic sources. Currently, there is considerable interest in examining the usefulness of these cells for conditions such as status epilepticus (SE) and chronic epilepsy. A prolonged seizure activity in SE triggers neurodegeneration in the limbic brain areas, which elicits epileptogenesis and evolves into a chronic epileptic state. Because of their potential for providing neuroprotection, diminishing inflammation and curbing epileptogenesis, early intervention with MNCs or MSCs appears attractive for treating SE as such effects may restrain the development of chronic epilepsy typified by spontaneous seizures and learning and memory impairments. Delayed administration of these cells after SE may also be useful for easing spontaneous seizures and cognitive dysfunction in chronic epilepsy. This concise review evaluates the current knowledge and outlook pertaining to MNC and MSC therapies for SE and chronic epilepsy. In the first section, the behavior of these cells in animal models of SE and their efficacy to restrain neurodegeneration, inflammation, and epileptogenesis are discussed. The competence of these cells for suppressing seizures and improving cognitive function in chronic epilepsy are conferred in the next section. The final segment ponders issues that need to be addressed to pave the way for clinical application of these cells for SE and chronic epilepsy.
Collapse
Affiliation(s)
- Satish Agadi
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White, Temple, Texas, USA.,Department of Pediatrics, McLane's Children's Hospital, Baylor Scott & White Health, Temple, Texas, USA
| | - Ashok K Shetty
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White, Temple, Texas, USA.,Research Service, Olin E. Teague Veterans Affairs Medical Center, Central Texas Veterans Health Care System, Temple, Texas, USA.,Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, Texas, USA
| |
Collapse
|
21
|
Enriched Environment Altered Aberrant Hippocampal Neurogenesis and Improved Long-Term Consequences After Temporal Lobe Epilepsy in Adult Rats. J Mol Neurosci 2015; 56:409-21. [DOI: 10.1007/s12031-015-0571-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Accepted: 04/21/2015] [Indexed: 10/23/2022]
|
22
|
Song C, Xu W, Zhang X, Wang S, Zhu G, Xiao T, Zhao M, Zhao C. CXCR4 Antagonist AMD3100 Suppresses the Long-Term Abnormal Structural Changes of Newborn Neurons in the Intraventricular Kainic Acid Model of Epilepsy. Mol Neurobiol 2015; 53:1518-1532. [PMID: 25650120 DOI: 10.1007/s12035-015-9102-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 01/15/2015] [Indexed: 12/19/2022]
Abstract
Abnormal hippocampal neurogenesis is a prominent feature of temporal lobe epilepsy (TLE) models, which is thought to contribute to abnormal brain activity. Stromal cell-derived factor-1 (SDF-1) and its specific receptor CXCR4 play important roles in adult neurogenesis. We investigated whether treatment with the CXCR4 antagonist AMD3100 suppressed aberrant hippocampal neurogenesis, as well as the long-term consequences in the intracerebroventricular kainic acid (ICVKA) model of epilepsy. Adult male rats were randomly assigned as control rats, rats subjected to status epilepticus (SE), and post-SE rats treated with AMD3100. Animals in each group were divided into two subgroups (acute stage and chronic stage). We used immunofluorescence staining of BrdU and DCX to analyze the hippocampal neurogenesis on post-SE days 10 or 74. Nissl staining and Timm staining were used to evaluate hippocampal damage and mossy fiber sprouting, respectively. On post-SE day 72, the frequency and mean duration of spontaneous seizures were measured by electroencephalography (EEG). Cognitive function was evaluated by Morris water maze testing on post-SE day 68. The ICVKA model of TLE resulted in aberrant neurogenesis such as altered proliferation, abnormal dendrite development of newborn neurons, as well as spontaneous seizures and spatial learning impairments. More importantly, AMD3100 treatment reversed the aberrant neurogenesis seen after TLE, which was accompanied by decreased long-term seizure activity, though improvement in spatial learning was not seen. AMD3100 could suppress long-term seizure activity and alter adult neurogenesis in the ICVKA model of TLE, which provided morphological evidences that AMD3100 might be beneficial for treating chronic epilepsy.
Collapse
Affiliation(s)
- Chengguang Song
- Department of Neurology, The First Affiliated Hospital, China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, 110001, Liaoning, People's Republic of China.,Department of Neurology, Benxi Central Hospital of China Medical University, Benxi, Liaoning, People's Republic of China
| | - Wangshu Xu
- Department of Neurology, The First Affiliated Hospital, China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, 110001, Liaoning, People's Republic of China
| | - Xiaoqian Zhang
- Department of Neurology, The First Affiliated Hospital, China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, 110001, Liaoning, People's Republic of China
| | - Shang Wang
- Department of Neurology, The First Affiliated Hospital, China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, 110001, Liaoning, People's Republic of China
| | - Gang Zhu
- Department of Psychiatry, The First Affiliated Hospital, China Medical University, Shenyang, Liaoning, People's Republic of China
| | - Ting Xiao
- Department of Dermatology, The First Affiliated Hospital, China Medical University, Shenyang, Liaoning, People's Republic of China.,Key Laboratory of Immunodermatology, Ministry of Health, Ministry of Education, Shenyang, Liaoning, People's Republic of China
| | - Mei Zhao
- Department of Cardiology, The Shengjing Affiliated Hospital, China Medical University, Shenyang, Liaoning, People's Republic of China
| | - Chuansheng Zhao
- Department of Neurology, The First Affiliated Hospital, China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, 110001, Liaoning, People's Republic of China.
| |
Collapse
|
23
|
Zhang W, Thamattoor AK, LeRoy C, Buckmaster PS. Surviving mossy cells enlarge and receive more excitatory synaptic input in a mouse model of temporal lobe epilepsy. Hippocampus 2014; 25:594-604. [PMID: 25488607 DOI: 10.1002/hipo.22396] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2014] [Indexed: 11/07/2022]
Abstract
Numerous hypotheses of temporal lobe epileptogenesis have been proposed, and several involve hippocampal mossy cells. Building on previous hypotheses we sought to test the possibility that after epileptogenic injuries surviving mossy cells develop into super-connected seizure-generating hub cells. If so, they might require more cellular machinery and consequently have larger somata, elongate their dendrites to receive more synaptic input, and display higher frequencies of miniature excitatory synaptic currents (mEPSCs). To test these possibilities pilocarpine-treated mice were evaluated using GluR2-immunocytochemistry, whole-cell recording, and biocytin-labeling. Epileptic pilocarpine-treated mice displayed substantial loss of GluR2-positive hilar neurons. Somata of surviving neurons were 1.4-times larger than in controls. Biocytin-labeled mossy cells also were larger in epileptic mice, but dendritic length per cell was not significantly different. The average frequency of mEPSCs of mossy cells recorded in the presence of tetrodotoxin and bicuculline was 3.2-times higher in epileptic pilocarpine-treated mice as compared to controls. Other parameters of mEPSCs were similar in both groups. Average input resistance of mossy cells in epileptic mice was reduced to 63% of controls, which is consistent with larger somata and would tend to make surviving mossy cells less excitable. Other intrinsic physiological characteristics examined were similar in both groups. Increased excitatory synaptic input is consistent with the hypothesis that surviving mossy cells develop into aberrantly super-connected seizure-generating hub cells, and soma hypertrophy is indirectly consistent with the possibility of axon sprouting. However, no obvious evidence of hyperexcitable intrinsic physiology was found. Furthermore, similar hypertrophy and hyper-connectivity has been reported for other neuron types in the dentate gyrus, suggesting mossy cells are not unique in this regard. Thus, findings of the present study reveal epilepsy-related changes in mossy cell anatomy and synaptic input but do not strongly support the hypothesis that mossy cells develop into seizure-generating hub cells.
Collapse
Affiliation(s)
- Wei Zhang
- Department of Comparative Medicine, Stanford University, Stanford, California
| | | | | | | |
Collapse
|
24
|
Yamawaki R, Thind K, Buckmaster PS. Blockade of excitatory synaptogenesis with proximal dendrites of dentate granule cells following rapamycin treatment in a mouse model of temporal lobe epilepsy. J Comp Neurol 2014; 523:281-97. [PMID: 25234294 DOI: 10.1002/cne.23681] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 09/09/2014] [Accepted: 09/16/2014] [Indexed: 12/13/2022]
Abstract
Inhibiting the mammalian target of rapamycin (mTOR) signaling pathway with rapamycin blocks granule cell axon (mossy fiber) sprouting after epileptogenic injuries, including pilocarpine-induced status epilepticus. However, it remains unclear whether axons from other types of neurons sprout into the inner molecular layer and synapse with granule cell dendrites despite rapamycin treatment. If so, other aberrant positive-feedback networks might develop. To test this possibility stereological electron microscopy was used to estimate the numbers of excitatory synapses in the inner molecular layer per hippocampus in pilocarpine-treated control mice, in mice 5 days after pilocarpine-induced status epilepticus, and after status epilepticus and daily treatment beginning 24 hours later with rapamycin or vehicle for 2 months. The optical fractionator method was used to estimate numbers of granule cells in Nissl-stained sections so that numbers of excitatory synapses in the inner molecular layer per granule cell could be calculated. Control mice had an average of 2,280 asymmetric synapses in the inner molecular layer per granule cell, which was reduced to 63% of controls 5 days after status epilepticus, recovered to 93% of controls in vehicle-treated mice 2 months after status epilepticus, but remained at only 63% of controls in rapamycin-treated mice. These findings reveal that rapamycin prevented excitatory axons from synapsing with proximal dendrites of granule cells and raise questions about the recurrent excitation hypothesis of temporal lobe epilepsy.
Collapse
Affiliation(s)
- Ruth Yamawaki
- Department of Comparative Medicine, Stanford University, Stanford, CA, 94305
| | | | | |
Collapse
|
25
|
Nomura S, Shimakawa S, Miyamoto R, Fukui M, Tamai H. 3-Methyl-1-phenyl-2-pyrazolin-5-one or N-acetylcysteine prevents hippocampal mossy fiber sprouting and rectifies subsequent convulsive susceptibility in a rat model of kainic acid-induced seizure ceased by pentobarbital. Brain Res 2014; 1590:65-74. [PMID: 24854122 DOI: 10.1016/j.brainres.2014.05.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 04/24/2014] [Accepted: 05/12/2014] [Indexed: 12/17/2022]
Abstract
There is accumulating evidence that reactive oxygen species are involved in the development of seizures under pathological conditions, and antioxidant treatments are a novel therapeutic approach for epilepsy. The kainic acid (KA) model of induced seizures has been widely used to study temporal lobe epilepsy. However, research on the use of free radical scavengers following KA-induced status epilepticus (SE) is limited. We examined whether antioxidants already used in humans could reduce hippocampal neuronal cell loss, mossy fiber sprouting and the acquisition of hyperexcitability when administered as a single dose after SE. The antioxidant 3-methyl-1-phenyl-2-pyrazolin-5-one (edaravone) (30mg/kg) or N-acetylcysteine (NAC) (30mg/kg) was administered after KA-induced SE ceased by pentobarbital. We evaluated neuronal cell viability 1 week after SE, determined the threshold for seizures induced by inhalation of flurothyl ether 12 weeks after SE, and examined the extent of mossy fiber sprouting 12 weeks after SE. We found that edaravone or NAC prevented neuronal cell loss and mossy fiber sprouting, and increased the threshold for seizures induced by flurothyl ether, even when administered after KA-induced SE. These results demonstrate that a single dose of edaravone or NAC can protect against neuronal cell loss and epileptogenesis when administered after SE ceased by pentobarbital.
Collapse
Affiliation(s)
- Shohei Nomura
- Department of Pediatrics, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan
| | - Shuichi Shimakawa
- Department of Pediatrics, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan.
| | - Ryohei Miyamoto
- Department of Pediatrics, Saiseikai Ibaraki Hospital, 2-1-45 Mitsukeyama, Ibaraki, Osaka 567-0035, Japan
| | - Miho Fukui
- Department of Pediatrics, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan
| | - Hiroshi Tamai
- Department of Pediatrics, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan
| |
Collapse
|
26
|
Tyson JA, Anderson SA. GABAergic interneuron transplants to study development and treat disease. Trends Neurosci 2014; 37:169-77. [PMID: 24508416 PMCID: PMC4396846 DOI: 10.1016/j.tins.2014.01.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/06/2014] [Accepted: 01/06/2014] [Indexed: 01/06/2023]
Abstract
Advances in stem cell technology have engendered keen interest in cell-based therapies for neurological disorders. Postnatal engraftments of most neuronal precursors result in little cellular migration, a crucial prerequisite for transplants to integrate within the host circuitry. This may occur because most neurons migrate along substrates, such as radial glial processes, that are not abundant in adults. However, cortical GABAergic interneurons migrate tangentially from the subcortical forebrain into the cerebral cortex. Accordingly, transplants of cortical interneuron precursors migrate extensively after engraftment into a variety of CNS tissues, where they can become synaptically connected with host circuitry. We review how this remarkable ability to integrate post-transplant is being applied to the development of cell-based therapies for a variety of CNS disorders.
Collapse
Affiliation(s)
- Jennifer A Tyson
- Department of Psychiatry, Weill Medical College of Cornell University, New York, NY 10021, USA; Department of Psychiatry, Children's Hospital of Philadelphia and University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Stewart A Anderson
- Department of Psychiatry, Children's Hospital of Philadelphia and University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
| |
Collapse
|
27
|
Buckmaster PS. Does mossy fiber sprouting give rise to the epileptic state? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 813:161-8. [PMID: 25012375 DOI: 10.1007/978-94-017-8914-1_13] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Many patients with temporal lobe epilepsy display structural changes in the seizure initiating zone, which includes the hippocampus. Structural changes in the hippocampus include granule cell axon (mossy fiber) sprouting. The role of mossy fiber sprouting in epileptogenesis is controversial. A popular view of temporal lobe epileptogenesis contends that precipitating brain insults trigger transient cascades of molecular and cellular events that permanently enhance excitability of neuronal networks through mechanisms including mossy fiber sprouting. However, recent evidence suggests there is no critical period for mossy fiber sprouting after an epileptogenic brain injury. Instead, findings from stereological electron microscopy and rapamycin-delayed mossy fiber sprouting in rodent models of temporal lobe epilepsy suggest a persistent, homeostatic mechanism exists to maintain a set level of excitatory synaptic input to granule cells. If so, a target level of mossy fiber sprouting might be determined shortly after a brain injury and then remain constant. Despite the static appearance of synaptic reorganization after its development, work by other investigators suggests there might be continual turnover of sprouted mossy fibers in epileptic patients and animal models. If so, there may be opportunities to reverse established mossy fiber sprouting. However, reversal of mossy fiber sprouting is unlikely to be antiepileptogenic, because blocking its development does not reduce seizure frequency in pilocarpine-treated mice. The challenge remains to identify which, if any, of the many other structural changes in the hippocampus are epileptogenic.
Collapse
Affiliation(s)
- Paul S Buckmaster
- Departments of Comparative Medicine and Neurology & Neurological Sciences, Stanford University, Stanford, CA, USA,
| |
Collapse
|
28
|
Shetty AK, Hattiangady B. Postnatal age governs the extent of differentiation of hippocampal CA1 and CA3 subfield neural stem/progenitor cells into neurons and oligodendrocytes. Int J Dev Neurosci 2013; 31:646-56. [PMID: 23743166 DOI: 10.1016/j.ijdevneu.2013.05.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 05/15/2013] [Accepted: 05/16/2013] [Indexed: 10/26/2022] Open
Abstract
While neural stem/progenitor cells (NSCs) in the dentate gyrus of the hippocampus have been extensively characterized, the behavior of NSCs in the CA1 and CA3 subfields of the hippocampus is mostly unclear. Therefore, we compared the in vitro behavior of NSCs expanded from the micro-dissected CA1 and CA3 subfields of postnatal day (PND) 4 and 12 Fischer 344 rats. A small fraction (∼1%) of dissociated cells from CA1 and CA3 subfields of both PND 4 and 12 hippocampi formed neurospheres in the presence of EGF and FGF-2. A vast majority of neurosphere cells expressed NSC markers such as nestin, Sox-2 and Musashi-1. Differentiation assays revealed the ability of these NSCs to give rise to neurons, astrocytes, and oligodendrocytes. Interestingly, the overall neuronal differentiation of NSCs from both subfields decreased with age (23-28% at PND4 to 5-10% at PND12) but the extent of oligodendrocyte differentiation from NSCs increased with age (24-32% at PND 4 to 45-55% at PND 12). Differentiation of NSCs into astrocytes was however unchanged (40-48%). Furthermore, NSCs from both subfields gave rise to GABA-ergic neurons including subclasses expressing markers such as calbindin, calretinin, neuropeptide Y and parvalbumin. However, the fraction of neurons that expressed GABA decreased between PND4 (59-67%) and PND 12 (25-38%). Additional analyses revealed the presence of proliferating NSC-like cells (i.e. cells expressing Ki-67 and Sox-2) in different strata of hippocampal CA1 and CA3 subfields of both PND4 and PND 12 animals. Thus, multipotent NSCs persist in both CA1 and CA3 subfields of the hippocampus in the postnatal period. Such NSCs also retain their ability to give rise to both GABA-ergic and non-GABA-ergic neurons. However, their overall neurogenic potential declines considerably in the early postnatal period.
Collapse
Affiliation(s)
- Ashok K Shetty
- Institute for Regenerative Medicine, Texas A&M Health Science Center College of Medicine at Scott & White, Temple, TX, USA; Research Service, Olin E. Teague Veterans' Medical Center, CTVHCS, Temple, TX, USA; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA; Division of Neurosurgery, Duke University Medical Center, Durham, NC, USA; Research and Surgery Services, Durham Veterans Affairs Medical Center, Durham, NC, USA.
| | | |
Collapse
|
29
|
Gao F, Liu Y, Li X, Wang Y, Wei D, Jiang W. Fingolimod (FTY720) inhibits neuroinflammation and attenuates spontaneous convulsions in lithium-pilocarpine induced status epilepticus in rat model. Pharmacol Biochem Behav 2012; 103:187-96. [PMID: 22960129 DOI: 10.1016/j.pbb.2012.08.025] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 08/17/2012] [Accepted: 08/25/2012] [Indexed: 11/29/2022]
Abstract
Accumulating evidence has shown that neuroinflammation plays a key role in epileptogenesis. However, the efficacy of anti-inflammatory agents for preventing epilepsy remains controversial. Fingolimod (FTY720), a sphingosine-1-phosphate (S1P) analog, has potent anti-inflammatory effects in multiple sclerosis (MS) patients and animal models. Here, we tested whether FTY720 could exert antiepileptogenic effects in an adult rat model of lithium-pilocarpine induced epilepsy. 24h after onset of status epilepticus (SE), the epileptic rats received saline or 1mg/kg FTY720 i.p. once daily for 14 consecutive days. Thereafter, spontaneous convulsions (SCs), mossy fiber sprouting (MFS), neuronal loss, activation of microglia and astrocytes, expressions of interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNFα) were evaluated in the SE rats. We found that FTY720 treatment reduced neuronal loss and decreased activation of microglia and astrocytes in hippocampus at four days post-SE. Simultaneously, abnormal expressions of IL-1β and TNFα in hippocampus were restrained by FTY720 treatment. In addition, neuroprotective effects of FTY720 were demonstrated by increasing neuronal nuclei (NeuN)-positive cells and decreasing Fluoro-Jade B (FJB)-positive cells in the hippocampus. During 21-34days post-SE, the incidence, duration, frequency and severity of SCs significantly decreased in FTY720 treated rats compared with saline treated rats. Aberrant MFS was also attenuated by FTY720 administration. These results suggest that FTY720 exerts anti-inflammatory and antiepileptogenic effects in lithium-pilocarpine model of epilepsy and it may provide a new therapeutic approach for prevention of epileptogenesis.
Collapse
Affiliation(s)
- Fei Gao
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, 17 Changle West Road, Xi'an 710032, China
| | | | | | | | | | | |
Collapse
|
30
|
Shetty AK, Hattiangady B, Rao MS, Shuai B. Neurogenesis response of middle-aged hippocampus to acute seizure activity. PLoS One 2012; 7:e43286. [PMID: 22912847 PMCID: PMC3422269 DOI: 10.1371/journal.pone.0043286] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 07/23/2012] [Indexed: 01/19/2023] Open
Abstract
Acute Seizure (AS) activity in young adult age conspicuously modifies hippocampal neurogenesis. This is epitomized by both increased addition of new neurons to the granule cell layer (GCL) by neural stem/progenitor cells (NSCs) in the dentate subgranular zone (SGZ), and greatly enhanced numbers of newly born neurons located abnormally in the dentate hilus (DH). Interestingly, AS activity in old age does not induce such changes in hippocampal neurogenesis. However, the effect of AS activity on neurogenesis in the middle-aged hippocampus is yet to be elucidated. We examined hippocampal neurogenesis in middle-aged F344 rats after a continuous AS activity for >4 hrs, induced through graded intraperitoneal injections of the kainic acid. We labeled newly born cells via daily intraperitoneal injections of the 5'-bromodeoxyuridine (BrdU) for 12 days, commencing from the day of induction of AS activity. AS activity enhanced the addition of newly born BrdU+ cells by 5.6 fold and newly born neurons (expressing both BrdU and doublecortin [DCX]) by 2.2 fold to the SGZ-GCL. Measurement of the total number of DCX+ newly born neurons also revealed a similar trend. Furthermore, AS activity increased DCX+ newly born neurons located ectopically in the DH (2.7 fold increase and 17% of total newly born neurons). This rate of ectopic migration is however considerably less than what was observed earlier for the young adult hippocampus after similar AS activity. Thus, the plasticity of hippocampal neurogenesis to AS activity in middle age is closer to its response observed in the young adult age. However, the extent of abnormal migration of newly born neurons into the DH is less than that of the young adult hippocampus after similar AS activity. These results also point out a highly divergent response of neurogenesis to AS activity between middle age and old age.
Collapse
Affiliation(s)
- Ashok K Shetty
- Research Service, Veterans Affairs Medical Centers of Durham, North Carolina, and Temple, Texas, United States of America.
| | | | | | | |
Collapse
|
31
|
Increased excitatory synaptic input to granule cells from hilar and CA3 regions in a rat model of temporal lobe epilepsy. J Neurosci 2012; 32:1183-96. [PMID: 22279204 DOI: 10.1523/jneurosci.5342-11.2012] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
One potential mechanism of temporal lobe epilepsy is recurrent excitation of dentate granule cells through aberrant sprouting of their axons (mossy fibers), which is found in many patients and animal models. However, correlations between the extent of mossy fiber sprouting and seizure frequency are weak. Additional potential sources of granule cell recurrent excitation that would not have been detected by markers of mossy fiber sprouting in previous studies include surviving mossy cells and proximal CA3 pyramidal cells. To test those possibilities in hippocampal slices from epileptic pilocarpine-treated rats, laser-scanning glutamate uncaging was used to randomly and focally activate neurons in the granule cell layer, hilus, and proximal CA3 pyramidal cell layer while measuring evoked EPSCs in normotopic granule cells. Consistent with mossy fiber sprouting, a higher proportion of glutamate-uncaging spots in the granule cell layer evoked EPSCs in epileptic rats compared with controls. In addition, stimulation spots in the hilus and proximal CA3 pyramidal cell layer were more likely to evoke EPSCs in epileptic rats, despite significant neuron loss in those regions. Furthermore, synaptic strength of recurrent excitatory inputs to granule cells from CA3 pyramidal cells and other granule cells was increased in epileptic rats. These findings reveal substantial levels of excessive, recurrent, excitatory synaptic input to granule cells from neurons in the hilus and proximal CA3 field. The aberrant development of these additional positive-feedback circuits might contribute to epileptogenesis in temporal lobe epilepsy.
Collapse
|
32
|
Lew FH, Buckmaster PS. Is there a critical period for mossy fiber sprouting in a mouse model of temporal lobe epilepsy? Epilepsia 2011; 52:2326-32. [PMID: 22092282 DOI: 10.1111/j.1528-1167.2011.03315.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
PURPOSE Dentate granule cell axon (mossy fiber) sprouting creates an aberrant positive-feedback circuit that might be epileptogenic. Presumably, mossy fiber sprouting is initiated by molecular signals, but it is unclear whether they are expressed transiently or persistently. If transient, there might be a critical period when short preventative treatments could permanently block mossy fiber sprouting. Alternatively, if signals persist, continuous treatment would be necessary. The present study tested whether temporary treatment with rapamycin has long-term effects on mossy fiber sprouting. METHODS Mice were treated daily with 1.5 mg/kg rapamycin or vehicle (i.p.) beginning 24 h after pilocarpine-induced status epilepticus. Mice were perfused for anatomic evaluation immediately after 2 months of treatment ("0 delay") or after an additional 6 months without treatment ("6-month delay"). One series of sections was Timm-stained, and an adjacent series was Nissl-stained. Stereologic methods were used to measure the volume of the granule cell layer plus molecular layer and the Timm-positive fraction. Numbers of Nissl-stained hilar neurons were estimated using the optical fractionator method. KEY FINDINGS At 0 delay, rapamycin-treated mice had significantly less black Timm staining in the granule cell layer plus molecular layer than vehicle-treated animals. However, by 6-month delay, Timm staining had increased significantly in mice that had been treated with rapamycin. Percentages of the granule cell layer plus molecular layer that were Timm-positive were high and similar in 0 delay vehicle-treated, 6-month delay vehicle-treated, and 6-month delay rapamycin-treated mice. Extent of hilar neuron loss was similar among all groups that experienced status epilepticus and, therefore, was not a confounding factor. Compared to naive controls, average volume of the granule cell layer plus molecular layer was larger in 0 delay vehicle-treated mice. The hypertrophy was partially suppressed in 0 delay rapamycin-treated mice. However, 6-month delay vehicle- and 6-month delay rapamycin-treated animals had similar average volumes of the granule cell layer plus molecular layer that were significantly larger than those of all other groups. SIGNIFICANCE Status epilepticus-induced mossy fiber sprouting and dentate gyrus hypertrophy were suppressed by systemic treatment with rapamycin but resumed after treatment ceased. These findings suggest that molecular signals that drive mossy fiber sprouting and dentate gyrus hypertrophy might persist for >2 months after status epilepticus in mice. Therefore, prolonged or continuous treatment might be required to permanently suppress mossy fiber sprouting.
Collapse
Affiliation(s)
- Felicia H Lew
- Department of Comparative Medicine, Stanford University, Stanford, California 94305, USA
| | | |
Collapse
|
33
|
De la Cruz E, Zhao M, Guo L, Ma H, Anderson SA, Schwartz TH. Interneuron progenitors attenuate the power of acute focal ictal discharges. Neurotherapeutics 2011; 8:763-73. [PMID: 21748528 PMCID: PMC3250298 DOI: 10.1007/s13311-011-0058-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Interneuron progenitors from the embryonic medial ganglionic eminence (MGE) can migrate, differentiate, and enhance local inhibition after transplantation into the postnatal cortex. Whether grafted MGE cells can reduce ictal activity in adult neocortex is unknown. We transplanted live MGE or killed cells (control) from pan green fluorescent protein expressing mice into adult mouse sensorimotor cortex. One week, 2 and 1/2 weeks, or 6 to 8 weeks after transplant, acute focal ictal epileptiform discharges were induced by injection of 4-aminopyridine (4-AP) 2 mm away from the site of transplantation. The local field potential of the events was recorded with 2 electrodes, 1 located in the 4-AP focus and the other 1 in the transplantation site. In all control groups and in the 1-week live cell transplant, 4-AP ictal discharges revealed no attenuation in power and duration from the onset site to the site of transplantation. However, 2.5 or 6 ~ 8 weeks after MGE transplants, there was a dramatic decrease in local field potential power at the MGE transplanted site with little decrease in ictal duration. Surprisingly, there was no relationship between grafted cell distribution or density and the degree of attenuation. As remarkably low graft densities still significantly reduced discharge power, these data provide further support for the therapeutic potential of interneuron precursor transplants in the treatment of neocortical epilepsy.
Collapse
Affiliation(s)
- Estanislao De la Cruz
- Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY 10065 USA
| | - Mingrui Zhao
- Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY 10065 USA
| | - Lihua Guo
- Department of Psychiatry, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY 10065 USA
| | - Hongtao Ma
- Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY 10065 USA
| | - Stewart A. Anderson
- Department of Psychiatry, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY 10065 USA
| | - Theodore H. Schwartz
- Departments of Neurological Surgery, Neurology and Neuroscience, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY 10065 USA
| |
Collapse
|
34
|
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.
Collapse
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.
| |
Collapse
|
35
|
Shetty AK. Promise of resveratrol for easing status epilepticus and epilepsy. Pharmacol Ther 2011; 131:269-86. [PMID: 21554899 PMCID: PMC3133838 DOI: 10.1016/j.pharmthera.2011.04.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 03/29/2011] [Indexed: 12/26/2022]
Abstract
Resveratrol (RESV; 3,5,4'-tri-hydroxy stilbene), a naturally occurring phytoalexin, is found at a high concentration in the skin of red grapes and red wine. RESV mediates a wide-range of biological activities, which comprise an increased life span, anti-ischemic, anti-cancer, antiviral, anti-aging and anti-inflammatory properties. Studies in several animal prototypes of brain injury suggest that RESV is an effective neuroprotective compound. Ability to enter the brain after a peripheral administration and no adverse effects on the brain or body are other features that are appealing for using this compound as a therapy for brain injury or neurodegenerative diseases. The goal of this review is to discuss the promise of RESV for treating acute seizures, preventing the acute seizure or status epilepticus induced development of chronic epilepsy, and easing the chronic epilepsy typified by spontaneous recurrent seizures and cognitive dysfunction. First, the various beneficial effects of RESV on the normal brain are discussed to provide a rationale for considering RESV treatment in the management of acute seizures and epilepsy. Next, the detrimental effects of acute seizures or status epilepticus on the hippocampus and the implications of post-status epilepticus changes in the hippocampus towards the occurrence of chronic epilepsy and cognitive dysfunction are summarized. The final segment evaluates studies that have used RESV as a neuroprotective compound against seizures, and proposes studies that are critically needed prior to the clinical application of RESV as a prophylaxis against the development of chronic epilepsy and cognitive dysfunction after an episode of status epilepticus or head injury.
Collapse
Affiliation(s)
- Ashok K Shetty
- Medical Research and Surgery Services, Veterans Affairs Medical Center, Durham, NC 27705, USA.
| |
Collapse
|
36
|
Shen H, Liu L, Huo Z, Lin Z. Hippocampal stem cell grafting-mediated recovery of injured hippocampus in the rat model of temporal lobe epilepsy. Int J Neurosci 2011; 120:647-54. [PMID: 20718693 DOI: 10.3109/00207454.2010.509526] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Hippocampal stem cells (HSCs) are considered promising donor cells to promote reorganization of degenerated regions of the injured hippocampus in the epileptic brain. However, the efficacy of HSC grafting for repairing injured hippocampus remains unclear. To address this issue, we transplanted neonatal rat HSCs into the right hippocampus in rats with kainite acid (KA)-induced epilepsy. The activity of the hippocampus and amygdala nucleus was monitored with electroencephalogram (EEG) throughout 24 weeks posttransplantation. Rats with grafted HSCs exhibited reduced frequency of epileptic wave discharge and a 50% decrease in the amplitude of discharge. At 1, 4, 8, and 24 weeks posttransplantation, the aberrant mossy fiber sprouting (MFS) was evaluated with Timm's stain and the number of CA3 pyramidal neurons was analyzed with Nissl staining. Aberrant MFS induced by KA-lesion was notably suppressed by HSC grafts beginning 4 weeks posttransplantation, and was most effective by 8 weeks. In addition, the loss of CA3 pyramidal neurons was partially restored and reached the most recovery at 8 weeks. Taken together, these results suggest that HSCs derived from the postnatal hippocampus offer a promising reparative effect on KA-induced epileptic brain.
Collapse
Affiliation(s)
- Hong Shen
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, China
| | | | | | | |
Collapse
|
37
|
Transplantation of Neural Stem Cells Overexpressing Cardiotrophin-1 Inhibits Sprouting of Hippocampal Mossy Fiber in a Rat Model of Status Epilepticus. Cell Biochem Biophys 2011; 61:367-70. [DOI: 10.1007/s12013-011-9219-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
38
|
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: 1.3] [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.
Collapse
|
39
|
Nivet E, Vignes M, Girard SD, Pierrisnard C, Baril N, Devèze A, Magnan J, Lanté F, Khrestchatisky M, Féron F, Roman FS. Engraftment of human nasal olfactory stem cells restores neuroplasticity in mice with hippocampal lesions. J Clin Invest 2011; 121:2808-20. [PMID: 21670501 DOI: 10.1172/jci44489] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2010] [Accepted: 04/27/2011] [Indexed: 12/15/2022] Open
Abstract
Stem cell-based therapy has been proposed as a potential means of treatment for a variety of brain disorders. Because ethical and technical issues have so far limited the clinical translation of research using embryonic/fetal cells and neural tissue, respectively, the search for alternative sources of therapeutic stem cells remains ongoing. Here, we report that upon transplantation into mice with chemically induced hippocampal lesions, human olfactory ecto-mesenchymal stem cells (OE-MSCs) - adult stem cells from human nasal olfactory lamina propria - migrated toward the sites of neural damage, where they differentiated into neurons. Additionally, transplanted OE-MSCs stimulated endogenous neurogenesis, restored synaptic transmission, and enhanced long-term potentiation. Mice that received transplanted OE-MSCs exhibited restoration of learning and memory on behavioral tests compared with lesioned, nontransplanted control mice. Similar results were obtained when OE-MSCs were injected into the cerebrospinal fluid. These data show that OE-MSCs can induce neurogenesis and contribute to restoration of hippocampal neuronal networks via trophic actions. They provide evidence that human olfactory tissue is a conceivable source of nervous system replacement cells. This stem cell subtype may be useful for a broad range of stem cell-related studies.
Collapse
Affiliation(s)
- Emmanuel Nivet
- Laboratoire de Neurobiologie des Processus Mnésiques, CNRS UMR-6149, Aix-Marseille Université; IFR Sciences du Cerveau et de Cognition, Marseille, France.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Kucharova K, Hefferan MP, Patel P, Marsala S, Nejime T, Miyanohara A, Marsala M, Drummond JC. Transplantation of rat synapsin-EGFP-labeled embryonic neurons into the intact and ischemic CA1 hippocampal region: distribution, phenotype, and axodendritic sprouting. Cell Transplant 2011; 20:1163-78. [PMID: 21669049 DOI: 10.3727/096368910x564544] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
A major limitation of neural transplantation studies is assessing the degree of host-graft interaction. In the present study, rat hippocampal/cortical embryonic neurons (E18) were infected with a lentivirus encoding enhanced green fluorescent protein (GFP) under control of the neuron-specific synapsin promoter, thus permitting robust identification of labeled neurons after in vivo grafting. Two weeks after transient forebrain ischemia or sham-surgery, GFP-expressing neurons were transplanted into CA1 hippocampal regions in immunosuppressed adult Wistar rats. The survival, distribution, phenotype, and axonal projections of GFP-immunoreactive (IR) positive transplanted neurons were evaluated in the sham-operated and ischemia- damaged CA1 hippocampal regions 4, 8, and 12 weeks after transplantation. In both experimental groups, we observed that the main phenotype of host-derived afferents projecting towards grafted GFP-IR neurons as well as transplant-derived GFP-IR efferents were glutamatergic in both animal groups. GFP axonal projections were seen in the nucleus accumbens, septal nuclei, and subiculum-known target areas of CA1 pyramidal neurons. Compared to sham-operated animals, GFP-IR neurons grafted into the ischemia-damaged CA1 migrated more extensively throughout a larger volume of host tissue, particularly in the stratum radiatum. Moreover, enhanced axonal sprouting and neuronal plasticity of grafted cells were evident in the hippocampus, subiculum, septal nuclei, and nucleus accumbens of the ischemia-damaged rats. Our study suggests that the adult rat brain retains some capacity to direct newly sprouting axons of transplanted embryonic neurons to the correct targets and that this capacity is enhanced in previously ischemia-injured forebrain.
Collapse
Affiliation(s)
- K Kucharova
- Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Waldau B, Hattiangady B, Kuruba R, Shetty AK. Medial ganglionic eminence-derived neural stem cell grafts ease spontaneous seizures and restore GDNF expression in a rat model of chronic temporal lobe epilepsy. Stem Cells 2010; 28:1153-64. [PMID: 20506409 DOI: 10.1002/stem.446] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Nearly 30% of patients with mesial temporal lobe epilepsy (TLE) are resistant to treatment with antiepileptic drugs. Neural stem cell (NSC) grafting into the hippocampus could offer an alternative therapy to hippocampal resection in these patients. As TLE is associated with reduced numbers of inhibitory gamma-amino butyric acid (GABA)-ergic interneurons and astrocytes expressing the anticonvulsant glial-derived neurotrophic factor (GDNF) in the hippocampus, we tested the hypothesis that grafting of NSCs that are capable of adding new GABA-ergic interneurons and GDNF-expressing astrocytes into the epileptic hippocampus restrains spontaneous recurrent motor seizures (SRMS) in chronic TLE. We grafted NSCs expanded in vitro from embryonic medial ganglionic eminence (MGE) into hippocampi of adult rats exhibiting chronic TLE with cognitive impairments. NSC grafting reduced frequencies of SRMS by 43% and stage V seizures by 90%. The duration of individual SRMS and the total time spent in seizures were reduced by 51 and 74%, respectively. Grafting did not improve the cognitive function however. Graft-derived cells (equivalent to approximately 28% of injected cells) were observed in various layers of the epileptic hippocampus where they differentiated into NeuN+ neurons (13%), S-100beta+ astrocytes (57%), and NG2+ oligodendrocyte-progenitors (3%). Furthermore, among graft-derived cells, 10% expressed GABA and 50% expressed GDNF. Additionally, NSC grafting restored GDNF in a vast majority of the hippocampal astrocytes but had no effect on neurogenesis. Thus, MGE-NSC therapy is efficacious for diminishing SRMS in chronic TLE. Addition of new GABA-ergic neurons and GDNF+ cells, and restoration of GDNF in the hippocampal astrocytes may underlie the therapeutic effect of MGE-NSC grafts.
Collapse
Affiliation(s)
- Ben Waldau
- Department of Surgery (Neurosurgery), Duke University Medical Center, Durham, North Carolina 27710, USA
| | | | | | | |
Collapse
|
42
|
Shetty AK, Hattiangady B, Rao MS. Vulnerability of hippocampal GABA-ergic interneurons to kainate-induced excitotoxic injury during old age. J Cell Mol Med 2010. [PMID: 20141618 DOI: 10.1111/j.1582-4934.2008.00675.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Hippocampal inhibitory interneurons expressing glutamate decarboxylase-67 (GAD-67) considerably decline in number during old age. Studies in young adult animals further suggest that hippocampal GAD-67+ interneuron population is highly vulnerable to excitotoxic injury. However, the relative susceptibility of residual GAD-67+ interneurons in the aged hippocampus to excitotoxic injury is unknown. To elucidate this, using both adult and aged F344 rats, we performed stereological counting of GAD-67+ interneurons in different layers of the dentate gyrus and CA1 & CA3 sub-fields, at 3 months post-excitotoxic hippocampal injury inflicted through an intracerebroventricular administration of kainic acid (KA). Substantial reductions of GAD-67+ interneurons were found in all hippocampal layers and sub-fields after KA-induced injury in adult animals. Contrastingly, there was no significant change in GAD-67+ interneuron population in any of the hippocampal layers and sub-fields following similar injury in aged animals. Furthermore, the stability of GAD-67+ interneurons in aged rats after KA was not attributable to milder injury, as the overall extent of KA-induced hippocampal principal neuron loss was comparable between adult and aged rats. Interestingly, because of the age-related disparity in vulnerability of interneurons to injury, the surviving GAD-67+ interneuron population in the injured aged hippocampus remained comparable to that observed in the injured adult hippocampus despite enduring significant reductions in interneuron number with aging. Thus, unlike in the adult hippocampus, an excitotoxic injury to the aged hippocampus does not result in significantly decreased numbers of GAD-67+ interneurons. Persistence of GAD-67+ interneuron population in the injured aged hippocampus likely reflects an age-related change in the response of GAD-67+ interneurons to excitotoxic hippocampal injury. These results have implications towards understanding mechanisms underlying the evolution of initial precipitating injury into temporal lobe epilepsy in the elderly population.
Collapse
Affiliation(s)
- Ashok K Shetty
- Medical Research and Surgery Services, Veterans Affairs Medical Center, Durham, NC, USA.
| | | | | |
Collapse
|
43
|
Shetty AK, Hattiangady B, Rao MS. Vulnerability of hippocampal GABA-ergic interneurons to kainate-induced excitotoxic injury during old age. J Cell Mol Med 2010; 13:2408-23. [PMID: 20141618 DOI: 10.1111/j.1582-4934.2009.00675.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Hippocampal inhibitory interneurons expressing glutamate decarboxylase-67 (GAD-67) considerably decline in number during old age. Studies in young adult animals further suggest that hippocampal GAD-67+ interneuron population is highly vulnerable to excitotoxic injury. However, the relative susceptibility of residual GAD-67+ interneurons in the aged hippocampus to excitotoxic injury is unknown. To elucidate this, using both adult and aged F344 rats, we performed stereological counting of GAD-67+ interneurons in different layers of the dentate gyrus and CA1 & CA3 sub-fields, at 3 months post-excitotoxic hippocampal injury inflicted through an intracerebroventricular administration of kainic acid (KA). Substantial reductions of GAD-67+ interneurons were found in all hippocampal layers and sub-fields after KA-induced injury in adult animals. Contrastingly, there was no significant change in GAD-67+ interneuron population in any of the hippocampal layers and sub-fields following similar injury in aged animals. Furthermore, the stability of GAD-67+ interneurons in aged rats after KA was not attributable to milder injury, as the overall extent of KA-induced hippocampal principal neuron loss was comparable between adult and aged rats. Interestingly, because of the age-related disparity in vulnerability of interneurons to injury, the surviving GAD-67+ interneuron population in the injured aged hippocampus remained comparable to that observed in the injured adult hippocampus despite enduring significant reductions in interneuron number with aging. Thus, unlike in the adult hippocampus, an excitotoxic injury to the aged hippocampus does not result in significantly decreased numbers of GAD-67+ interneurons. Persistence of GAD-67+ interneuron population in the injured aged hippocampus likely reflects an age-related change in the response of GAD-67+ interneurons to excitotoxic hippocampal injury. These results have implications towards understanding mechanisms underlying the evolution of initial precipitating injury into temporal lobe epilepsy in the elderly population.
Collapse
Affiliation(s)
- Ashok K Shetty
- Medical Research and Surgery Services, Veterans Affairs Medical Center, Durham, NC, USA.
| | | | | |
Collapse
|
44
|
Boison D. Cell and gene therapies for refractory epilepsy. Curr Neuropharmacol 2010; 5:115-25. [PMID: 18615179 DOI: 10.2174/157015907780866938] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2006] [Revised: 03/07/2007] [Accepted: 03/08/2007] [Indexed: 12/20/2022] Open
Abstract
Despite recent advances in the development of antiepileptic drugs, refractory epilepsy remains a major clinical problem affecting up to 35% of patients with partial epilepsy. Currently, there are few therapies that affect the underlying disease process. Therefore, novel therapeutic concepts are urgently needed. The recent development of experimental cell and gene therapies may offer several advantages compared to conventional systemic pharmacotherapy: (i) Specificity to underlying pathogenetic mechanisms by rational design; (ii) specificity to epileptogenic networks by focal delivery; and (iii) avoidance of side effects. A number of naturally occurring brain substances, such as GABA, adenosine, and the neuropeptides galanin and neuropeptide Y, may function as endogenous anticonvulsants and, in addition, may interact with the process of epileptogenesis. Unfortunately, the systemic application of these compounds is compromised by limited bioavailability, poor penetration of the blood-brain barrier, or the widespread systemic distribution of their respective receptors. Therefore, in recent years a new field of cell and gene-based neuropharmacology has emerged, aimed at either delivering endogenous anticonvulsant compounds by focal intracerebral transplantation of bioengineered cells (ex vivo gene therapy), or by inducing epileptogenic brain areas to produce these compounds in situ (in vivo gene therapy). In this review, recent efforts to develop GABA-, adenosine-, galanin-, and neuropeptide Y- based cell and gene therapies are discussed. The neurochemical rationales for using these compounds are discussed, the advantages of focal applications are highlighted and preclinical cell transplantation and gene therapy studies are critically evaluated. Although many promising data have been generated recently, potential problems, such as long-term therapeutic efficacy, long-term safety, and efficacy in clinically relevant animal models, need to be addressed before clinical applications can be contemplated.
Collapse
Affiliation(s)
- Detlev Boison
- RS Dow Neurobiology Laboratories, Legacy Research, Portland, OR 97232, USA.
| |
Collapse
|
45
|
Liu X, Wen F, Yang J, Chen L, Wei YQ. A review of current applications of mass spectrometry for neuroproteomics in epilepsy. MASS SPECTROMETRY REVIEWS 2010; 29:197-246. [PMID: 19598206 DOI: 10.1002/mas.20243] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The brain is unquestionably the most fascinating organ, and the hippocampus is crucial in memory storage and retrieval and plays an important role in stress response. In temporal lobe epilepsy (TLE), the seizure origin typically involves the hippocampal formation. Despite tremendous progress, current knowledge falls short of being able to explain its function. An emerging approach toward an improved understanding of the complex molecular mechanisms that underlie functions of the brain and hippocampus is neuroproteomics. Mass spectrometry has been widely used to analyze biological samples, and has evolved into an indispensable tool for proteomics research. In this review, we present a general overview of the application of mass spectrometry in proteomics, summarize neuroproteomics and systems biology-based discovery of protein biomarkers for epilepsy, discuss the methodology needed to explore the epileptic hippocampus proteome, and also focus on applications of ingenuity pathway analysis (IPA) in disease research. This neuroproteomics survey presents a framework for large-scale protein research in epilepsy that can be applied for immediate epileptic biomarker discovery and the far-reaching systems biology understanding of the protein regulatory networks. Ultimately, knowledge attained through neuroproteomics could lead to clinical diagnostics and therapeutics to lessen the burden of epilepsy on society.
Collapse
Affiliation(s)
- Xinyu Liu
- National Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | | | | | | | | |
Collapse
|
46
|
Zipancic I, Calcagnotto ME, Piquer-Gil M, Mello LE, Álvarez-Dolado M. Transplant of GABAergic Precursors Restores Hippocampal Inhibitory Function in a Mouse Model of Seizure Susceptibility. Cell Transplant 2010; 19:549-64. [DOI: 10.3727/096368910x491383] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Defects in GABAergic function can cause epilepsy. In the last years, cell-based therapies have attempted to correct these defects with disparate success on animal models of epilepsy. Recently, we demonstrated that medial ganglionic eminence (MGE)-derived cells grafted into the neonatal normal brain migrate and differentiate into functional mature GABAergic interneurons. These cells are able to modulate the local level of GABA-mediated synaptic inhibition, which suggests their suitability for cell-based therapies. However, it is unclear whether they can integrate in the host circuitry and rescue the loss of inhibition in pathological conditions. Thus, as proof of principle, we grafted MGE-derived cells into a mouse model of seizure susceptibility caused by specific elimination of GABAergic interneuron subpopulations in the mouse hippocampus after injection of the neurotoxic saporin conjugated to substance P (SSP-Sap). This ablation was associated with significant decrease in inhibitory postsynaptic currents (IPSC) on CA1 pyramidal cells and increased seizure susceptibility induced by pentylenetetrazol (PTZ). Grafting of GFP+ MGE-derived cells in SSP-Sap-treated mice repopulates the hippocampal ablated zone with cells expressing molecular markers of mature interneurons. Interestingly, IPSC kinetics on CA1 pyramidal cells of ablated hippocampus significantly increased after transplantation, reaching levels similar to the normal mice. More importantly, this was associated with reduction in seizure severity and decrease in postseizure mortality induced by PTZ. Our data show that MGE-derived cells fulfill most of the requirements for an appropriate cell-based therapy, and indicate their suitability for neurological conditions where a modulation of synaptic inhibition is needed, such as epilepsy.
Collapse
Affiliation(s)
- I. Zipancic
- Department of Cell Therapy and Regenerative Medicine, Andalusian Center for Molecular Biology and Regenerative Medicine (CABIMER), Seville, Spain
- Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain
| | - M. E. Calcagnotto
- Department of Cell Therapy and Regenerative Medicine, Andalusian Center for Molecular Biology and Regenerative Medicine (CABIMER), Seville, Spain
| | - M. Piquer-Gil
- Department of Cell Therapy and Regenerative Medicine, Andalusian Center for Molecular Biology and Regenerative Medicine (CABIMER), Seville, Spain
| | - L. E. Mello
- Department of Physiology, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - M. Álvarez-Dolado
- Department of Cell Therapy and Regenerative Medicine, Andalusian Center for Molecular Biology and Regenerative Medicine (CABIMER), Seville, Spain
| |
Collapse
|
47
|
Shetty AK, Hattiangady B, Rao MS, Shuai B. Deafferentation enhances neurogenesis in the young and middle aged hippocampus but not in the aged hippocampus. Hippocampus 2010; 21:631-46. [PMID: 20333732 DOI: 10.1002/hipo.20776] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2010] [Indexed: 12/13/2022]
Abstract
Increased neurogenesis in the dentate gyrus (DG) after brain insults such as excitotoxic lesions, seizures, or stroke is a well known phenomenon in the young hippocampus. This plasticity reflects an innate compensatory response of neural stem cells (NSCs) in the young hippocampus to preserve function or minimize damage after injury. However, injuries to the middle-aged and aged hippocampi elicit either no or dampened neurogenesis response, which could be due to an altered plasticity of NSCs and/or the hippocampus with age. We examined whether the plasticity of NSCs to increase neurogenesis in response to a milder injury such as partial deafferentation is preserved during aging. We quantified DG neurogenesis in the hippocampus of young, middle-aged, and aged F344 rats after partial deafferentation. A partial deafferentation of the left hippocampus without any apparent cell loss was induced via administration of Kainic acid (0.5 μg in 1.0 μl) into the right lateral ventricle of the brain. In this model, degeneration of CA3 pyramidal neurons and dentate hilar neurons in the right hippocampus results in loss of commissural axons which leads to partial deafferentation of the dendrites of dentate granule cells and CA1-CA3 pyramidal neurons in the left hippocampus. Quantification of newly born cells that are added to the dentate granule cell layer at postdeafferentation days 4-15 using 5'-bromodeoxyuridine (BrdU) labeling revealed greatly increased addition of newly born cells (∼three fold increase) in the deafferented young and middle-aged hippocampi but not in the deafferented aged hippocampus. Measurement of newly born neurons using doublecortin (DCX) immunostaining also revealed similar findings. Analyses using BrdU-DCX dual immunofluorescence demonstrated no changes in neuronal fate-choice decision of newly born cells after deafferentation, in comparison to the age-matched naive hippocampus in all age groups. Thus, the plasticity of hippocampal NSCs to increase DG neurogenesis in response to a milder injury such as partial hippocampal deafferentation is preserved until middle age but lost at old age.
Collapse
Affiliation(s)
- Ashok K Shetty
- Medical Research and Surgery Services, Veterans Affairs Medical Center, Durham, North Carolina, USA.
| | | | | | | |
Collapse
|
48
|
Hattiangady B, Shetty AK. Decreased neuronal differentiation of newly generated cells underlies reduced hippocampal neurogenesis in chronic temporal lobe epilepsy. Hippocampus 2010; 20:97-112. [PMID: 19309040 DOI: 10.1002/hipo.20594] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Hippocampal neurogenesis declines substantially in chronic temporal lobe epilepsy (TLE). However, it is unclear whether this decline is linked to altered production of new cells and/or diminished survival and neuronal fate-choice decision of newly born cells. We quantified different components of hippocampal neurogenesis in rats exhibiting chronic TLE. Through intraperitoneal administration of 5'-bromodeoxyuridine (BrdU) for 12 days, we measured numbers of newly born cells in the subgranular zone-granule cell layer (SGZ-GCL) at 24 h and 2.5 months post-BrdU administration. Furthermore, the differentiation of newly added cells into neurons and glia was quantified via dual immunofluorescence for BrdU and various markers of neurons and glia. Addition of new cells to the SGZ-GCL over 12 days was comparable between the chronically epileptic hippocampus and the age-matched intact hippocampus. Furthermore, comparison of BrdU+ cells measured at 24 h and 2.5 months post-BrdU administration revealed similar survival of newly born cells between the two groups. However, only 4-5% of newly born cells (i.e., BrdU+ cells) differentiated into neurons in the chronically epileptic hippocampus, in comparison to 73-80% of such cells exhibiting neuronal differentiation in the intact hippocampus. Moreover, differentiation of newly born cells into S-100beta+ astrocytes or NG2+ oligodendrocyte progenitors increased to approximately 79% in the chronically epileptic hippocampus from approximately 25% observed in the intact hippocampus. Interestingly, the extent of proliferation of astrocytes and microglia (identified through Ki-67 and S-100beta and Ki-67 and OX-42 dual immunofluorescence) in the SGZ-GCL was similar between the chronically epileptic hippocampus and the age-matched intact hippocampus, implying that the proliferation of neural stem/progenitor cells in the SGZ-GCL of the chronically epileptic hippocampus was not obscured by an increased division of glia. Thus, severely diminished DG neurogenesis in chronic TLE is not associated with either decreased production of new cells or reduced survival of newly born cells in the SGZ-GCL. Rather, it is linked to a dramatic decline in the neuronal fate-choice decision of newly generated cells. Overall, the differentiation of newly born cells turns mainly into glia with chronic TLE from predominantly neuronal differentiation seen in control conditions.
Collapse
Affiliation(s)
- Bharathi Hattiangady
- Department of Surgery (Neurosurgery), Duke University Medical Center, Durham, North Carolina 27710, USA
| | | |
Collapse
|
49
|
Radojevic V, Kapfhammer JP. Directed fiber outgrowth from transplanted embryonic cortex-derived neurospheres in the adult mouse brain. Neural Plast 2010; 2009:852492. [PMID: 20169102 PMCID: PMC2821778 DOI: 10.1155/2009/852492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 10/22/2009] [Accepted: 11/19/2009] [Indexed: 11/18/2022] Open
Abstract
Neural transplantation has emerged as an attractive strategy for the replacement of neurons that have been lost in the central nervous system. Multipotent neural progenitor cells are potentially useful as donor cells to repopulate the degenerated regions. One important aspect of a transplantation strategy is whether transplanted cells are capable of fiber outgrowth with the aim of rebuilding axonal connections within the host brain. To address this issue, we expanded neuronal progenitor from the cortex of embryonic day 15 ubiquitously green fluorescent protein-expressing transgenic mice as neurospheres in vitro and grafted them into the entorhinal cortex of 8-week-old mice immediately after a perforant pathway lesion. After transplantation into a host brain with a lesion of the entorhino-hippocampal projection, the neurosphere-derived cells extended long fiber projections directed towards the dentate gyrus. Our results indicate that transplantation of neurosphere-derived cells might be a promising strategy to replace lost or damaged axonal projections.
Collapse
Affiliation(s)
- Vesna Radojevic
- HNO Klinik, ZLF 411, University of Basel, Hebelstr. 20, 4031 Basel, Switzerland
- Department of Biomedicine, Anatomical Institute, University of Basel, Pestalozzistr. 20, 4056 Basel, Switzerland
| | - Josef P. Kapfhammer
- Department of Biomedicine, Anatomical Institute, University of Basel, Pestalozzistr. 20, 4056 Basel, Switzerland
| |
Collapse
|
50
|
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
|