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Sajan SA, Gradisch R, Vogel FD, Coffey AJ, Salyakina D, Soler D, Jayakar P, Jayakar A, Bianconi SE, Cooper AH, Liu S, William N, Benkel-Herrenbrück I, Maiwald R, Heller C, Biskup S, Leiz S, Westphal DS, Wagner M, Clarke A, Stockner T, Ernst M, Kesari A, Krenn M. De novo variants in GABRA4 are associated with a neurological phenotype including developmental delay, behavioral abnormalities and epilepsy. Eur J Hum Genet 2024; 32:912-919. [PMID: 38565639 PMCID: PMC11291759 DOI: 10.1038/s41431-024-01600-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 02/03/2024] [Accepted: 03/19/2024] [Indexed: 04/04/2024] Open
Abstract
Nine out of 19 genes encoding GABAA receptor subunits have been linked to monogenic syndromes characterized by seizures and developmental disorders. Previously, we reported the de novo variant p.(Thr300Ile) in GABRA4 in a patient with epilepsy and neurodevelopmental abnormalities. However, no new cases have been reported since then. Through an international collaboration, we collected molecular and phenotype data of individuals carrying de novo variants in GABRA4. Patients and their parents were investigated either by exome or genome sequencing, followed by targeted Sanger sequencing in some cases. All variants within the transmembrane domain, including the previously reported p.(Thr300Ile) variant, were characterized in silico and analyzed by molecular dynamics (MD) simulation studies. We identified three novel de novo missense variants in GABRA4 (NM_000809.4): c.797 C > T, p.(Pro266Leu), c.899 C > A, p.(Thr300Asn), and c.634 G > A, p.(Val212Ile). The p.(Thr300Asn) variant impacts the same codon as the previously reported variant p.(Thr300Ile) and likely arose post-zygotically as evidenced by sequencing oral mucosal cells. Overlapping phenotypes among affected individuals included developmental delay (4/4), epileptiform EEG abnormalities (3/4), attention deficits (3/4), seizures (2/4), autistic features (2/4) and structural brain abnormalities (2/4). MD simulations of the three variants within the transmembrane domain of the receptor indicate that sub-microsecond scale dynamics differ between wild-type and mutated subunits. Taken together, our findings further corroborate an association between GABRA4 and a neurological phenotype including variable neurodevelopmental, behavioral and epileptic abnormalities.
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Affiliation(s)
- Samin A Sajan
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Ralph Gradisch
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Florian D Vogel
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Alison J Coffey
- lllumina Clinical Services Laboratory, Illumina Inc., San Diego, CA, USA
| | - Daria Salyakina
- Personalized Medicine and Health Outcomes Research, Nicklaus Children's Hospital, Miami, FL, USA
| | - Diana Soler
- Personalized Medicine and Health Outcomes Research, Nicklaus Children's Hospital, Miami, FL, USA
| | - Parul Jayakar
- Division of Genetics and Metabolism, Nicklaus Children's Hospital, Miami, FL, USA
| | - Anuj Jayakar
- Department of Neurology, Division of Epilepsy, Nicklaus Children's Hospital, Miami, FL, USA
| | | | | | | | | | | | - Robert Maiwald
- Medizinisches Versorgungszentrum für Gerinnungsdiagnostik und Medizinische Genetik Köln, Köln, Germany
| | | | - Saskia Biskup
- Zentrum für Humangenetik, Tübingen, Germany
- Center for Genomics and Transcriptomics (CeGaT), Tübingen, Germany
| | - Steffen Leiz
- Division of Neuropediatrics, Klinikum Dritter Orden, Munich, Germany
| | - Dominik S Westphal
- Institute of Human Genetics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
- Department of Internal Medicine I, School of Medicine & Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Matias Wagner
- Institute of Human Genetics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Amy Clarke
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Thomas Stockner
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Margot Ernst
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Akanchha Kesari
- lllumina Clinical Services Laboratory, Illumina Inc., San Diego, CA, USA
| | - Martin Krenn
- Department of Neurology, Medical University of Vienna, Vienna, Austria.
- Comprehensive Center for Clinical Neurosciences & Mental Health, Medical University of Vienna, Vienna, Austria.
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He Q, Li R, Zhong N, Ma J, Nie F, Zhang R. The role and molecular mechanisms of the early growth response 3 gene in schizophrenia. Am J Med Genet B Neuropsychiatr Genet 2024; 195:e32969. [PMID: 38327141 DOI: 10.1002/ajmg.b.32969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 01/15/2024] [Accepted: 01/22/2024] [Indexed: 02/09/2024]
Abstract
Schizophrenia is a chronic, debilitating mental illness caused by both genetic and environmental factors. Genetic factors play a major role in schizophrenia development. Early growth response 3 (EGR3) is a member of the EGR family, which is associated with schizophrenia. Accumulating studies have investigated the relationship between EGR3 and schizophrenia. However, the role of EGR3 in schizophrenia pathogenesis remains unclear. In the present review, we focus on the progress of research related to the role of EGR3 in schizophrenia, including association studies between EGR3 and schizophrenia, abnormal gene expressional analysis of EGR3 in schizophrenia, biological function studies of EGR3 in schizophrenia, the molecular regulatory mechanism of EGR3 and schizophrenia susceptibility candidate genes, and possible role of EGR3 in the immune system function in schizophrenia. In summary, EGR3 is a schizophrenia risk candidate factor and has comprehensive regulatory roles in schizophrenia pathogenesis. Further studies investigating the molecular mechanisms of EGR3 in schizophrenia are warranted for understanding the pathophysiology of this disorder as well as the development of new therapeutic strategies for the treatment and control of this disorder.
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Affiliation(s)
- Qi He
- School of Basic Medicine, Shaanxi Key Laboratory of Acupuncture and Medicine, Shannxi University of Chinese Medicine, Xianyang, Shaanxi, China
| | - Ruochun Li
- Department of Medical Technology, Guiyang Healthcare Vocational University, Guiyang, Guizhou, China
| | - Nannan Zhong
- Department of Medical Technology, Guiyang Healthcare Vocational University, Guiyang, Guizhou, China
| | - Jie Ma
- Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Fayi Nie
- School of Basic Medicine, Shaanxi Key Laboratory of Acupuncture and Medicine, Shannxi University of Chinese Medicine, Xianyang, Shaanxi, China
| | - Rui Zhang
- Department of Medical Technology, Guiyang Healthcare Vocational University, Guiyang, Guizhou, China
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Burke CT, Vitko I, Straub J, Nylund EO, Gawda A, Blair K, Sullivan KA, Ergun L, Ottolini M, Patel MK, Perez-Reyes E. EpiPro, a Novel, Synthetic, Activity-Regulated Promoter That Targets Hyperactive Neurons in Epilepsy for Gene Therapy Applications. Int J Mol Sci 2023; 24:14467. [PMID: 37833914 PMCID: PMC10572392 DOI: 10.3390/ijms241914467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/16/2023] [Accepted: 09/21/2023] [Indexed: 10/15/2023] Open
Abstract
Epileptogenesis is characterized by intrinsic changes in neuronal firing, resulting in hyperactive neurons and the subsequent generation of seizure activity. These alterations are accompanied by changes in gene transcription networks, first with the activation of early-immediate genes and later with the long-term activation of genes involved in memory. Our objective was to engineer a promoter containing binding sites for activity-dependent transcription factors upregulated in chronic epilepsy (EpiPro) and validate it in multiple rodent models of epilepsy. First, we assessed the activity dependence of EpiPro: initial electrophysiology studies found that EpiPro-driven GFP expression was associated with increased firing rates when compared with unlabeled neurons, and the assessment of EpiPro-driven GFP expression revealed that GFP expression was increased ~150× after status epilepticus. Following this, we compared EpiPro-driven GFP expression in two rodent models of epilepsy, rat lithium/pilocarpine and mouse electrical kindling. In rodents with chronic epilepsy, GFP expression was increased in most neurons, but particularly in dentate granule cells, providing in vivo evidence to support the "breakdown of the dentate gate" hypothesis of limbic epileptogenesis. Finally, we assessed the time course of EpiPro activation and found that it was rapidly induced after seizures, with inactivation following over weeks, confirming EpiPro's potential utility as a gene therapy driver for epilepsy.
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Affiliation(s)
- Cassidy T. Burke
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Iuliia Vitko
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Justyna Straub
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Elsa O. Nylund
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Agnieszka Gawda
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Kathryn Blair
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Kyle A. Sullivan
- Computational and Predictive Biology, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
| | - Lara Ergun
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Matteo Ottolini
- Department of Anesthesiology, University of Virginia, Charlottesville, VA 22908, USA (M.K.P.)
| | - Manoj K. Patel
- Department of Anesthesiology, University of Virginia, Charlottesville, VA 22908, USA (M.K.P.)
- UVA Brain Institute, University of Virginia, Charlottesville, VA 22908, USA
| | - Edward Perez-Reyes
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
- UVA Brain Institute, University of Virginia, Charlottesville, VA 22908, USA
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Meyers KT, Damphousse CC, Ozols AB, Campbell JM, Newbern JM, Hu C, Marrone DF, Gallitano AL. Serial electroconvulsive Seizure alters dendritic complexity and promotes cellular proliferation in the mouse dentate gyrus; a role for Egr3. Brain Stimul 2023; 16:889-900. [PMID: 37146791 PMCID: PMC10776161 DOI: 10.1016/j.brs.2023.04.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/19/2023] [Accepted: 04/25/2023] [Indexed: 05/07/2023] Open
Abstract
BACKGROUND Despite being one of the safest, most effective treatments for severe mood disorders, the therapeutic mechanisms of electroconvulsive therapy remain unknown. Electroconvulsive seizure (ECS) induces rapid, high-level expression of immediate early genes (IEGs) and brain-derived neurotrophic factor (BDNF), in addition to stimulation of neurogenesis and dendritic remodeling of dentate gyrus (DG) neurons. We have previously shown that this upregulation of BDNF fails to occur in the hippocampus of mice lacking the IEG Egr3. Since BDNF influences neurogenesis and dendritic remodeling, we hypothesized that Egr3-/- mice will exhibit deficits in neurogenesis and dendritic remodeling in response to ECS. OBJECTIVE To test this hypothesis, we examined dendritic remodeling and cellular proliferation in the DG of Egr3-/- and wild-type mice following repeated ECS. METHODS Mice received 10 daily ECSs. Dendritic morphology was examined in Golgi-Cox-stained tissue and cellular proliferation was analyzed through bromodeoxyuridine (BrdU) immunohistochemistry and confocal imaging. RESULTS Serial ECS in mice results in dendritic remodeling, increased spine density, and cellular proliferation in the DG. Loss of Egr3 alters the dendritic remodeling induced by serial ECS but does not change the number of dendritic spines or cellular proliferation consequences of ECS. CONCLUSION Egr3 influences the dendritic remodeling induced by ECS but is not required for ECS-induced proliferation of hippocampal DG cells.
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Affiliation(s)
- K T Meyers
- Interdisciplinary Graduate Program in Neuroscience, Arizona State University, Tempe, AZ, 85281, USA; Basic Medical Sciences, University of Arizona College of Medicine - Phoenix, Phoenix, AZ, 85004, USA
| | - C C Damphousse
- Psychology, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
| | - A B Ozols
- Basic Medical Sciences, University of Arizona College of Medicine - Phoenix, Phoenix, AZ, 85004, USA
| | - J M Campbell
- Basic Medical Sciences, University of Arizona College of Medicine - Phoenix, Phoenix, AZ, 85004, USA
| | - J M Newbern
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA
| | - C Hu
- Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health - Phoenix, 714 E Van Buren St #119, Phoenix, AZ, 85006, USA
| | - D F Marrone
- Psychology, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada.
| | - A L Gallitano
- Basic Medical Sciences, University of Arizona College of Medicine - Phoenix, Phoenix, AZ, 85004, USA.
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CaMKIV mediates spine growth deficiency of hippocampal neurons by regulation of EGR3/BDNF signal axis in congenital hypothyroidism. Cell Death Dis 2022; 8:482. [PMID: 36473844 PMCID: PMC9723595 DOI: 10.1038/s41420-022-01270-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 11/13/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022]
Abstract
Congenital hypothyroidism (CH) will cause cognitive impairment in the condition of delayed treatment. The hippocampus is one of the most affected tissues by CH, in which the functional structures of hippocampal neurons manifest deficiency due to aberrant expression of effector molecules. The Ca2+/Calmodulin-dependent protein kinase, CaMKIV, is downregulated in the hippocampal neurons, influencing the growth of dendritic spines in response to CH. However, the underlying mechanism is not fully elucidated. In the present study, the early growth response factor 3 (EGR3) was regulated by CaMKIV in the hippocampal neurons of CH rat pups, as was analyzed by transcriptome sequencing and in vitro cell experiments. EGR3 localized within hippocampal neurons in CA1, CA3, and dentate gyrus regions. Deficient EGR3 in the primary hippocampal neurons significantly reduced the density of dendritic spines by downregulating the expression of BDNF, and such effects could be rescued by supplementing recombinant BDNF protein. Taken together, CH mediates cognitive impairment of pups through the inactivation of CaMKIV in the hippocampal neurons, which decreases the expression of EGR3 and further reduces the production of BDNF, thereby impairing the growth of dendritic spines. Identifying CaMKIV/EGR3/BDNF pathway in the hippocampal neurons in the context of CH will benefit the drug development of intellectual disability caused by CH.
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de Souza Aranha Garcia-Gomes M, Yamamoto PK, Massironi SMG, Galvis-Alonso OY, Mejia J, Zanatto DA, Alexandre-Ribeiro SR, Ienne S, Mori CMC. Alteration of hippocampal Egr3, GABA A receptors, Il-1β, Il6 and Ccl3 expression in audiogenic tremor mice after seizure. Epilepsy Behav 2022; 137:108962. [PMID: 36356419 DOI: 10.1016/j.yebeh.2022.108962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/18/2022] [Accepted: 10/15/2022] [Indexed: 11/09/2022]
Abstract
Neuroinflammation plays a protective role in the brain; however, in neurological diseases such as epilepsy, overactivated neuroinflammation, along with overexpression of inflammatory mediators, can cause neuronal tissue damage, which can trigger seizures due to loss of ionic or neurotransmitter homeostasis. Therefore, we aimed to evaluate mRNA expression levels of proinflammatory cytokines, early growth response factor 3 (Egr3), and GABA A receptors in the hippocampus of naive audiogenic mutant tremor mice, and stimulated tremor mice after a seizure. Gene expression of Il-1β, Il-6, Tnf-α, Ccl2, Ccl3, Egr3, Gabra1, and Gabra4 from hippocampal samples of naive and stimulated tremor mice were measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Relative to resistant mice, Ccl3 gene expression was increased and Il6 was decreased in the hippocampus of naïve tremor mice. Thirty minutes after a seizure, Ccl3 and Il-1β mRNA expression were decreased (p < 0.0001; p = 0.0034, respectively) while Il6 was increased (p = 0.0052) in stimulated tremor mice, relative to naïve animals. In addition, Egr3, Gabra1, and Gabra4 mRNA expression was decreased in the hippocampus of naive tremor mice, relative to resistant mice, which increased 30 minutes after a seizure (p = 0.0496; p = 0.0447, and p = 0.0011, respectively), relative to naïve animals. In conclusion, overexpression of Ccl3 in the hippocampus of naive tremor mice, followed by downregulation soon after seizure in stimulated tremor mice, could be involved in changes in the blood-brain barrier (BBB) permeability in epilepsy. Il-1β may be involved in hippocampal downregulation of GABA A receptors of naive tremor mice, characterizing an important mechanism in audiogenic seizures triggering. Hippocampal alterations of proinflammatory cytokines, Egr3, and GABA A receptors in tremor mice reinforce them as an alternative tool to modeling temporal lobe epilepsy.
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Affiliation(s)
| | - Pedro Kenzo Yamamoto
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil
| | | | | | - Jorge Mejia
- Hospital Israelita Albert Einstein, São Paulo, Brazil
| | - Dennis Albert Zanatto
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil
| | | | - Susan Ienne
- Core Facility for Scientific Research - University of São Paulo (CEFAP-USP/GENIAL (Genome Investigation and Analysis Laboratory), Brazil
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Rodent Models of Audiogenic Epilepsy: Genetic Aspects, Advantages, Current Problems and Perspectives. Biomedicines 2022; 10:biomedicines10112934. [PMID: 36428502 PMCID: PMC9687921 DOI: 10.3390/biomedicines10112934] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/10/2022] [Accepted: 11/11/2022] [Indexed: 11/18/2022] Open
Abstract
Animal models of epilepsy are of great importance in epileptology. They are used to study the mechanisms of epileptogenesis, and search for new genes and regulatory pathways involved in the development of epilepsy as well as screening new antiepileptic drugs. Today, many methods of modeling epilepsy in animals are used, including electroconvulsive, pharmacological in intact animals, and genetic, with the predisposition for spontaneous or refractory epileptic seizures. Due to the simplicity of manipulation and universality, genetic models of audiogenic epilepsy in rodents stand out among this diversity. We tried to combine data on the genetics of audiogenic epilepsy in rodents, the relevance of various models of audiogenic epilepsy to certain epileptic syndromes in humans, and the advantages of using of rodent strains predisposed to audiogenic epilepsy in current epileptology.
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Mitra S, Thomas SA, Martin JA, Williams J, Woodhouse K, Chandra R, Li JX, Lobo MK, Sim FJ, Dietz DM. EGR3 regulates opioid-related nociception and motivation in male rats. Psychopharmacology (Berl) 2022; 239:3539-3550. [PMID: 36098762 PMCID: PMC10094589 DOI: 10.1007/s00213-022-06226-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 08/24/2022] [Indexed: 01/11/2023]
Abstract
Chronic pain can be a debilitating condition, leading to profound changes in nearly every aspect of life. However, the reliance on opioids such as oxycodone for pain management is thought to initiate dependence and addiction liability. The neurobiological intersection at which opioids relieve pain and possibly transition to addiction is poorly understood. Using RNA sequencing pathway analysis in rats with complete Freund's adjuvant (CFA)-induced chronic inflammation, we found that the transcriptional signatures in the medial prefrontal cortex (mPFC; a brain region where pain and reward signals integrate) elicited by CFA in combination with oxycodone differed from those elicited by CFA or oxycodone alone. However, the expression of Egr3 was augmented in all animals receiving oxycodone. Furthermore, virus-mediated overexpression of EGR3 in the mPFC increased mechanical pain relief but not the affective aspect of pain in animals receiving oxycodone, whereas pharmacological inhibition of EGR3 via NFAT attenuated mechanical pain relief. Egr3 overexpression also increased the motivation to obtain oxycodone infusions in a progressive ratio test without altering the acquisition or maintenance of oxycodone self-administration. Taken together, these data suggest that EGR3 in the mPFC is at the intersection of nociceptive and addictive-like behaviors.
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Affiliation(s)
- Swarup Mitra
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA.
- Department of Biomedical Sciences, John C. Edwards School of Medicine, Marshall University, 1700, 3rd Avenue, Huntington, WV, 25755, USA.
| | - Shruthi A Thomas
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Jennifer A Martin
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Jamal Williams
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Kristen Woodhouse
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Ramesh Chandra
- Department of Anatomy and Neurobiology, University of Maryland, Baltimore, MD, USA
| | - Jun Xu Li
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - Mary Kay Lobo
- Department of Anatomy and Neurobiology, University of Maryland, Baltimore, MD, USA
| | - Fraser J Sim
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA
| | - David M Dietz
- Program in Neuroscience, Department of Pharmacology and Toxicology, The State University of New York at Buffalo, 955 Main Street, Buffalo, NY, 14203, USA.
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Identification of activity-induced Egr3-dependent genes reveals genes associated with DNA damage response and schizophrenia. Transl Psychiatry 2022; 12:320. [PMID: 35941129 PMCID: PMC9360026 DOI: 10.1038/s41398-022-02069-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 07/05/2022] [Accepted: 07/12/2022] [Indexed: 11/23/2022] Open
Abstract
Bioinformatics and network studies have identified the immediate early gene transcription factor early growth response 3 (EGR3) as a master regulator of genes differentially expressed in the brains of patients with neuropsychiatric illnesses ranging from schizophrenia and bipolar disorder to Alzheimer's disease. However, few studies have identified and validated Egr3-dependent genes in the mammalian brain. We have previously shown that Egr3 is required for stress-responsive behavior, memory, and hippocampal long-term depression in mice. To identify Egr3-dependent genes that may regulate these processes, we conducted an expression microarray on hippocampi from wildtype (WT) and Egr3-/- mice following electroconvulsive seizure (ECS), a stimulus that induces maximal expression of immediate early genes including Egr3. We identified 69 genes that were differentially expressed between WT and Egr3-/- mice one hour following ECS. Bioinformatic analyses showed that many of these are altered in, or associated with, schizophrenia, including Mef2c and Calb2. Enrichr pathway analysis revealed the GADD45 (growth arrest and DNA-damage-inducible) family (Gadd45b, Gadd45g) as a leading group of differentially expressed genes. Together with differentially expressed genes in the AP-1 transcription factor family genes (Fos, Fosb), and the centromere organization protein Cenpa, these results revealed that Egr3 is required for activity-dependent expression of genes involved in the DNA damage response. Our findings show that EGR3 is critical for the expression of genes that are mis-expressed in schizophrenia and reveal a novel requirement for EGR3 in the expression of genes involved in activity-induced DNA damage response.
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Tipton AE, Russek SJ. Regulation of Inhibitory Signaling at the Receptor and Cellular Level; Advances in Our Understanding of GABAergic Neurotransmission and the Mechanisms by Which It Is Disrupted in Epilepsy. Front Synaptic Neurosci 2022; 14:914374. [PMID: 35874848 PMCID: PMC9302637 DOI: 10.3389/fnsyn.2022.914374] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/17/2022] [Indexed: 11/13/2022] Open
Abstract
Inhibitory signaling in the brain organizes the neural circuits that orchestrate how living creatures interact with the world around them and how they build representations of objects and ideas. Without tight control at multiple points of cellular engagement, the brain’s inhibitory systems would run down and the ability to extract meaningful information from excitatory events would be lost leaving behind a system vulnerable to seizures and to cognitive decline. In this review, we will cover many of the salient features that have emerged regarding the dynamic regulation of inhibitory signaling seen through the lens of cell biology with an emphasis on the major building blocks, the ligand-gated ion channel receptors that are the first transduction point when the neurotransmitter GABA is released into the synapse. Epilepsy association will be used to indicate importance of key proteins and their pathways to brain function and to introduce novel areas for therapeutic intervention.
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Affiliation(s)
- Allison E. Tipton
- Graduate Program for Neuroscience, Boston University, Boston, MA, United States
- Biomolecular Pharmacology Program, Boston University School of Medicine, Boston, MA, United States
- Boston University MD/PhD Training Program, Boston, MA, United States
| | - Shelley J. Russek
- Biomolecular Pharmacology Program, Boston University School of Medicine, Boston, MA, United States
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
- Center for Systems Neuroscience, Boston University, Boston, MA, United States
- Boston University MD/PhD Training Program, Boston, MA, United States
- *Correspondence: Shelley J. Russek,
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11
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Gill PS, Dweep H, Rose S, Wickramasinghe PJ, Vyas KK, McCullough S, Porter-Gill PA, Frye RE. Integrated microRNA–mRNA Expression Profiling Identifies Novel Targets and Networks Associated with Autism. J Pers Med 2022; 12:jpm12060920. [PMID: 35743705 PMCID: PMC9225282 DOI: 10.3390/jpm12060920] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/23/2022] [Accepted: 05/27/2022] [Indexed: 01/27/2023] Open
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder, with mutations in hundreds of genes contributing to its risk. Herein, we studied lymphoblastoid cell lines (LCLs) from children diagnosed with autistic disorder (n = 10) and controls (n = 7) using RNA and miRNA sequencing profiles. The sequencing analysis identified 1700 genes and 102 miRNAs differentially expressed between the ASD and control LCLs (p ≤ 0.05). The top upregulated genes were GABRA4, AUTS2, and IL27, and the top upregulated miRNAs were hsa-miR-6813-3p, hsa-miR-221-5p, and hsa-miR-21-5p. The RT-qPCR analysis confirmed the sequencing results for randomly selected candidates: AUTS2, FMR1, PTEN, hsa-miR-15a-5p, hsa-miR-92a-3p, and hsa-miR-125b-5p. The functional enrichment analysis showed pathways involved in ASD control proliferation of neuronal cells, cell death of immune cells, epilepsy or neurodevelopmental disorders, WNT and PTEN signaling, apoptosis, and cancer. The integration of mRNA and miRNA sequencing profiles by miRWalk2.0 identified correlated changes in miRNAs and their targets’ expression. The integration analysis found significantly dysregulated miRNA–gene pairs in ASD. Overall, these findings suggest that mRNA and miRNA expression profiles in ASD are greatly altered in LCLs and reveal numerous miRNA–gene interactions that regulate critical pathways involved in the proliferation of neuronal cells, cell death of immune cells, and neuronal development.
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Affiliation(s)
- Pritmohinder S. Gill
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR 72202, USA;
- Arkansas Children′s Research Institute, Little Rock, AR 72202, USA; (K.K.V.); (S.M.); (P.A.P.-G.)
- Correspondence: ; Tel.: +1-501-364-2743
| | - Harsh Dweep
- The Wistar Institute, 3601 Spruce St., Philadelphia, PA 19104, USA; (H.D.); (P.J.W.)
| | - Shannon Rose
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR 72202, USA;
- Arkansas Children′s Research Institute, Little Rock, AR 72202, USA; (K.K.V.); (S.M.); (P.A.P.-G.)
| | | | - Kanan K. Vyas
- Arkansas Children′s Research Institute, Little Rock, AR 72202, USA; (K.K.V.); (S.M.); (P.A.P.-G.)
| | - Sandra McCullough
- Arkansas Children′s Research Institute, Little Rock, AR 72202, USA; (K.K.V.); (S.M.); (P.A.P.-G.)
| | - Patricia A. Porter-Gill
- Arkansas Children′s Research Institute, Little Rock, AR 72202, USA; (K.K.V.); (S.M.); (P.A.P.-G.)
| | - Richard E. Frye
- Barrow Neurological Institute at Phoenix Children′s Hospital, Phoenix, AZ 85016, USA;
- Department of Child Health, University of Arizona College of Medicine, Phoenix, AZ 85004, USA
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12
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Vogel FD, Krenn M, Westphal DS, Graf E, Wagner M, Leiz S, Koniuszewski F, Augé‐Stock M, Kramer G, Scholze P, Ernst M. A de novo missense variant in
GABRA4
alters receptor function in an epileptic and neurodevelopmental phenotype. Epilepsia 2022; 63:e35-e41. [PMID: 35152403 PMCID: PMC9304230 DOI: 10.1111/epi.17188] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 01/06/2022] [Accepted: 01/31/2022] [Indexed: 11/26/2022]
Abstract
Variants in γ‐aminobutyric acid A (GABAA) receptor genes cause different forms of epilepsy and neurodevelopmental disorders. To date, GABRA4, encoding the α4‐subunit, has not been associated with a monogenic condition. However, preclinical evidence points toward seizure susceptibility. Here, we report a de novo missense variant in GABRA4 (c.899C>T, p.Thr300Ile) in an individual with early‐onset drug‐resistant epilepsy and neurodevelopmental abnormalities. An electrophysiological characterization of the variant, which is located in the pore‐forming domain, shows accelerated desensitization and a lack of seizure‐protective neurosteroid function. In conclusion, our findings strongly suggest an association between de novo variation in GABRA4 and a neurodevelopmental disorder with epilepsy.
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Affiliation(s)
- Florian D. Vogel
- Department of Pathobiology of the Nervous System Center for Brain Research Medical University Vienna Vienna Austria
| | - Martin Krenn
- Department of Neurology Medical University of Vienna Vienna Austria
- Institute of Human Genetics School of Medicine Klinikum rechts der Isar Technical University of Munich Munich Germany
| | - Dominik S. Westphal
- Institute of Human Genetics School of Medicine Klinikum rechts der Isar Technical University of Munich Munich Germany
- Department of Internal Medicine I School of Medicine Klinikum rechts der Isar Technical University of Munich Munich Germany
| | - Elisabeth Graf
- Institute of Human Genetics School of Medicine Klinikum rechts der Isar Technical University of Munich Munich Germany
| | - Matias Wagner
- Institute of Human Genetics School of Medicine Klinikum rechts der Isar Technical University of Munich Munich Germany
- Institute of Neurogenomics Helmholtz Zentrum München Neuherberg Germany
- Department of Pediatrics Dr. von Hauner Children's Hospital LMU University Hospital Munich Germany
- Division of Pediatric Neurology LMU Center for Development and Children with Medical Complexity Ludwig‐Maximilians‐University Munich Munich Germany
| | - Steffen Leiz
- Divison of Neuropediatrics Klinikum Dritter Orden Munich Germany
| | - Filip Koniuszewski
- Department of Pathobiology of the Nervous System Center for Brain Research Medical University Vienna Vienna Austria
| | - Maximilian Augé‐Stock
- Department of Pathobiology of the Nervous System Center for Brain Research Medical University Vienna Vienna Austria
| | - Georg Kramer
- Department of Pathobiology of the Nervous System Center for Brain Research Medical University Vienna Vienna Austria
| | - Petra Scholze
- Department of Pathobiology of the Nervous System Center for Brain Research Medical University Vienna Vienna Austria
| | - Margot Ernst
- Department of Pathobiology of the Nervous System Center for Brain Research Medical University Vienna Vienna Austria
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13
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Birey F, Li MY, Gordon A, Thete MV, Valencia AM, Revah O, Paşca AM, Geschwind DH, Paşca SP. Dissecting the molecular basis of human interneuron migration in forebrain assembloids from Timothy syndrome. Cell Stem Cell 2021; 29:248-264.e7. [PMID: 34990580 DOI: 10.1016/j.stem.2021.11.011] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 10/19/2021] [Accepted: 11/24/2021] [Indexed: 02/06/2023]
Abstract
Defects in interneuron migration can disrupt the assembly of cortical circuits and lead to neuropsychiatric disease. Using forebrain assembloids derived by integration of cortical and ventral forebrain organoids, we have previously discovered a cortical interneuron migration defect in Timothy syndrome (TS), a severe neurodevelopmental disease caused by a mutation in the L-type calcium channel (LTCC) Cav1.2. Here, we find that acute pharmacological modulation of Cav1.2 can regulate the saltation length, but not the frequency, of interneuron migration in TS. Interestingly, the defect in saltation length is related to aberrant actomyosin and myosin light chain (MLC) phosphorylation, while the defect in saltation frequency is driven by enhanced γ-aminobutyric acid (GABA) sensitivity and can be restored by GABA-A receptor antagonism. Finally, we describe hypersynchronous hCS network activity in TS that is exacerbated by interneuron migration. Taken together, these studies reveal a complex role of LTCC function in human cortical interneuron migration and strategies to restore deficits in the context of disease.
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Affiliation(s)
- Fikri Birey
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Min-Yin Li
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Aaron Gordon
- Program in Neurogenetics, Department of Neurology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Mayuri V Thete
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Alfredo M Valencia
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Omer Revah
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Anca M Paşca
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Pediatrics, Division of Neonatology, Stanford University, Stanford, CA 94305, USA
| | - Daniel H Geschwind
- Program in Neurogenetics, Department of Neurology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA; Center for Autism Research and Treatment, Semel Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA; Institute of Precision Health, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Sergiu P Paşca
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA.
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14
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Regulation of GABA A Receptors Induced by the Activation of L-Type Voltage-Gated Calcium Channels. MEMBRANES 2021; 11:membranes11070486. [PMID: 34209589 PMCID: PMC8304739 DOI: 10.3390/membranes11070486] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/23/2021] [Accepted: 06/25/2021] [Indexed: 12/30/2022]
Abstract
GABAA receptors are pentameric ion channels that mediate most synaptic and tonic extrasynaptic inhibitory transmissions in the central nervous system. There are multiple GABAA receptor subtypes constructed from 19 different subunits in mammals that exhibit different regional and subcellular distributions and distinct pharmacological properties. Dysfunctional alterations of GABAA receptors are associated with various neuropsychiatric disorders. Short- and long-term plastic changes in GABAA receptors can be induced by the activation of different intracellular signaling pathways that are triggered, under physiological and pathological conditions, by calcium entering through voltage-gated calcium channels. This review discusses several mechanisms of regulation of GABAA receptor function that result from the activation of L-type voltage gated calcium channels. Calcium influx via these channels activates different signaling cascades that lead to changes in GABAA receptor transcription, phosphorylation, trafficking, and synaptic clustering, thus regulating the inhibitory synaptic strength. These plastic mechanisms regulate the interplay of synaptic excitation and inhibition that is crucial for the normal function of neuronal circuits.
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15
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Rodriguez-Acevedo AJ, Gordon LG, Waddell N, Hollway G, Vadlamudi L. Developing a gene panel for pharmacoresistant epilepsy: a review of epilepsy pharmacogenetics. Pharmacogenomics 2021; 22:225-234. [PMID: 33666520 DOI: 10.2217/pgs-2020-0145] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Evaluating genes involved in the pharmacodynamics and pharmacokinetics of epilepsy drugs is critical to better understand pharmacoresistant epilepsy. We reviewed the pharmacogenetics literature on six antiseizure medicines (carbamazepine, perampanel, lamotrigine, levetiracetam, sodium valproate and zonisamide) and compared the genes found with those present on epilepsy gene panels using a functional annotation pathway analysis. Little overlap was found between the two gene lists; pharmacogenetic genes are mainly involved in detoxification processes, while epilepsy panel genes are involved in cell signaling and gene expression. Our work provides support for a specific pharmacoresistant epilepsy gene panel to assist antiseizure medicine selection, enabling personalized approaches to treatment. Future efforts will seek to include this panel in genomic analyses of pharmacoresistant patients, to determine clinical utility and patient treatment responses.
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Affiliation(s)
- Astrid J Rodriguez-Acevedo
- Department of Population Health, QIMR Berghofer Medical Research Institute, 300 Herston Road, Brisbane, QLD, 4006, Australia
| | - Louisa G Gordon
- Department of Population Health, QIMR Berghofer Medical Research Institute, 300 Herston Road, Brisbane, QLD, 4006, Australia.,School of Nursing, Queensland University of Technology, Kelvin Grove, Brisbane, QLD, 4059, Australia.,School of Public Health, The University of Queensland, Brisbane, QLD, Australia
| | - Nicola Waddell
- Department of Population Health, QIMR Berghofer Medical Research Institute, 300 Herston Road, Brisbane, QLD, 4006, Australia.,GenomiQa Pty Ltd, Brisbane, QLD, Australia
| | - Georgina Hollway
- Department of Population Health, QIMR Berghofer Medical Research Institute, 300 Herston Road, Brisbane, QLD, 4006, Australia.,GenomiQa Pty Ltd, Brisbane, QLD, Australia
| | - Lata Vadlamudi
- The University of Queensland, UQ Centre for Clinical Research, Herston, Brisbane, QLD, 4029, Australia.,Department of Neurology, Royal Brisbane & Women's Hospital, Herston, Brisbane, QLD, 4029, Australia
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16
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Major Elements in the Upstream of Three Gorges Reservoir: An Investigation of Chemical Weathering and Water Quality during Flood Events. WATER 2021. [DOI: 10.3390/w13040454] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Rivers transport terrestrial matter into the ocean, constituting a fundamental channel between inland and oceanic ecosystem and affect global climate change. To reveal chemical weathering processes and environmental health risks during flood periods, water samples were collected in the upper reaches of Three Gorges Reservoir (TGR) in 2020. HCO3− and Ca2+ were the most abundant anions and cations of the river water, respectively. The range of HCO3− concentration was between 1.81 and 3.02 mmol/L, while the mean content of Ca2+ was 1.03 mmol/L. The results of the Piper diagram and element ratios revealed that the river solutes were mainly contributed by carbonate weathering and gypsum-rich evaporite dissolution. A mass balance model indicated that the contribution order of sources to cations in the main channel (Yibin-Luzhou) was evaporites > carbonates > atmospheric input > silicates. The order in the Chongqing—Three Gorges Dam was carbonates > atmospheric input > evaporites > silicates. These results showed a lithologic control on hydrochemical characteristics. Most sampling sites were suitable for agricultural irrigation according to the water quality assessment. However, indexes sodium adsorption ratio (SAR) and soluble sodium percentage (Na%) were higher than 1.0 in Yibin-Luzhou and 30% in Yibin–Chongqing, respectively, suggesting a potential sodium hazard. In addition, except Tuojiang River and Shennong River, the risk of sodium hazard in tributaries was relatively low. High Na+ concentration in irrigation water can damage soil structure and function and ultimately affect agricultural production. Water quality in the upstream of a Piper diagram should attract enough attention.
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17
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Singh S, Singh TG, Rehni AK. An Insight into Molecular Mechanisms and Novel Therapeutic Approaches in Epileptogenesis. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2021; 19:750-779. [PMID: 32914725 DOI: 10.2174/1871527319666200910153827] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 11/22/2022]
Abstract
Epilepsy is the second most common neurological disease with abnormal neural activity involving the activation of various intracellular signalling transduction mechanisms. The molecular and system biology mechanisms responsible for epileptogenesis are not well defined or understood. Neuroinflammation, neurodegeneration and Epigenetic modification elicit epileptogenesis. The excessive neuronal activities in the brain are associated with neurochemical changes underlying the deleterious consequences of excitotoxicity. The prolonged repetitive excessive neuronal activities extended to brain tissue injury by the activation of microglia regulating abnormal neuroglia remodelling and monocyte infiltration in response to brain lesions inducing axonal sprouting contributing to neurodegeneration. The alteration of various downstream transduction pathways resulted in intracellular stress responses associating endoplasmic reticulum, mitochondrial and lysosomal dysfunction, activation of nucleases, proteases mediated neuronal death. The recently novel pharmacological agents modulate various receptors like mTOR, COX-2, TRK, JAK-STAT, epigenetic modulators and neurosteroids are used for attenuation of epileptogenesis. Whereas the various molecular changes like the mutation of the cell surface, nuclear receptor and ion channels focusing on repetitive episodic seizures have been explored by preclinical and clinical studies. Despite effective pharmacotherapy for epilepsy, the inadequate understanding of precise mechanisms, drug resistance and therapeutic failure are the current fundamental problems in epilepsy. Therefore, the novel pharmacological approaches evaluated for efficacy on experimental models of epilepsy need to be identified and validated. In addition, we need to understand the downstream signalling pathways of new targets for the treatment of epilepsy. This review emphasizes on the current state of novel molecular targets as therapeutic approaches and future directions for the management of epileptogenesis. Novel pharmacological approaches and clinical exploration are essential to make new frontiers in curing epilepsy.
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Affiliation(s)
- Shareen Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | | | - Ashish Kumar Rehni
- Cerebral Vascular Disease Research Laboratories, Department of Neurology and Neuroscience Program, University of Miami School of Medicine, Miami, Florida 33101, United States
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18
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Barker JS, Hines RM. Regulation of GABA A Receptor Subunit Expression in Substance Use Disorders. Int J Mol Sci 2020; 21:ijms21124445. [PMID: 32580510 PMCID: PMC7352578 DOI: 10.3390/ijms21124445] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/17/2020] [Accepted: 06/19/2020] [Indexed: 01/02/2023] Open
Abstract
The modulation of neuronal cell firing is mediated by the release of the neurotransmitter GABA (γ-aminobuytric acid), which binds to two major families of receptors. The ionotropic GABAA receptors (GABAARs) are composed of five distinct subunits that vary in expression by brain region and cell type. The action of GABA on GABAARs is modulated by a variety of clinically and pharmacologically important drugs such as benzodiazepines and alcohol. Exposure to and abuse of these substances disrupts homeostasis and induces plasticity in GABAergic neurotransmission, often via the regulation of receptor expression. Here, we review the regulation of GABAAR subunit expression in adaptive and pathological plasticity, with a focus on substance use. We examine the factors influencing the expression of GABAAR subunit genes including the regulation of the 5′ and 3′ untranslated regions, variations in DNA methylation, immediate early genes and transcription factors that regulate subunit expression, translational and post-translational modifications, and other forms of receptor regulation beyond expression. Advancing our understanding of the factors regulating GABAAR subunit expression during adaptive plasticity, as well as during substance use and withdrawal will provide insight into the role of GABAergic signaling in substance use disorders, and contribute to the development of novel targeted therapies.
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19
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Díaz-Rodríguez SM, López-López D, Herrero-Turrión MJ, Gómez-Nieto R, Canal-Alonso A, Lopéz DE. Inferior Colliculus Transcriptome After Status Epilepticus in the Genetically Audiogenic Seizure-Prone Hamster GASH/Sal. Front Neurosci 2020; 14:508. [PMID: 32528245 PMCID: PMC7264424 DOI: 10.3389/fnins.2020.00508] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 04/22/2020] [Indexed: 01/31/2023] Open
Abstract
The Genetic Audiogenic Seizure Hamster from Salamanca (GASH/Sal), an animal model of reflex epilepsy, exhibits generalized tonic–clonic seizures in response to loud sound with the epileptogenic focus localized in the inferior colliculus (IC). Ictal events in seizure-prone strains cause gene deregulation in the epileptogenic focus, which can provide insights into the epileptogenic mechanisms. Thus, the present study aimed to determine the expression profile of key genes in the IC of the GASH/Sal after the status epilepticus. For such purpose, we used RNA-Seq to perform a comparative study between the IC transcriptome of GASH/Sal and that of control hamsters both subjected to loud sound stimulation. After filtering for normalization and gene selection, a total of 36 genes were declared differentially expressed from the RNA-seq analysis in the IC. A set of differentially expressed genes were validated by RT-qPCR showing significant differentially expression between GASH/Sal hamsters and Syrian control hamsters. The confirmed differentially expressed genes were classified on ontological categories associated with epileptogenic events similar to those produced by generalized tonic seizures in humans. Subsequently, based on the result of metabolomics, we found the interleukin-4 and 13-signaling, and nucleoside transport as presumably altered routes in the GASH/Sal model. This research suggests that seizures in GASH/Sal hamsters are generated by multiple molecular substrates, which activate biological processes, molecular processes, cellular components and metabolic pathways associated with epileptogenic events similar to those produced by tonic seizures in humans. Therefore, our study supports the use of the GASH/Sal as a valuable animal model for epilepsy research, toward establishing correlations with human epilepsy and searching new biomarkers of epileptogenesis.
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Affiliation(s)
- Sandra M Díaz-Rodríguez
- Institute of Neurosciences of Castilla y León, University of Salamanca, Salamanca, Spain.,Institute of Biomedical Research of Salamanca, University of Salamanca, Salamanca, Spain.,Department of Cellular Biology and Pathology, University of Salamanca, Salamanca, Spain
| | - Daniel López-López
- Institute of Neurosciences of Castilla y León, University of Salamanca, Salamanca, Spain
| | - Manuel J Herrero-Turrión
- Institute of Neurosciences of Castilla y León, University of Salamanca, Salamanca, Spain.,Institute of Biomedical Research of Salamanca, University of Salamanca, Salamanca, Spain.,Neurological Tissue Bank INCYL (BTN-INCYL), Salamanca, Spain
| | - Ricardo Gómez-Nieto
- Institute of Neurosciences of Castilla y León, University of Salamanca, Salamanca, Spain.,Institute of Biomedical Research of Salamanca, University of Salamanca, Salamanca, Spain.,Department of Cellular Biology and Pathology, University of Salamanca, Salamanca, Spain
| | - Angel Canal-Alonso
- Institute of Biomedical Research of Salamanca, University of Salamanca, Salamanca, Spain.,BISITE Research Group, University of Salamanca, Salamanca, Spain
| | - Dolores E Lopéz
- Institute of Neurosciences of Castilla y León, University of Salamanca, Salamanca, Spain.,Institute of Biomedical Research of Salamanca, University of Salamanca, Salamanca, Spain.,Department of Cellular Biology and Pathology, University of Salamanca, Salamanca, Spain
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20
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Fan C, Gao Y, Liang G, Huang L, Wang J, Yang X, Shi Y, Dräger UC, Zhong M, Gao TM, Yang X. Transcriptomics of Gabra4 knockout mice reveals common NMDAR pathways underlying autism, memory, and epilepsy. Mol Autism 2020; 11:13. [PMID: 32033586 PMCID: PMC7007694 DOI: 10.1186/s13229-020-0318-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 01/26/2020] [Indexed: 12/16/2022] Open
Abstract
Autism spectrum disorder (ASD) is a neuronal developmental disorder with impaired social interaction and communication, often with abnormal intelligence and comorbidity with epilepsy. Disturbances in synaptic transmission, including the GABAergic, glutamatergic, and serotonergic systems, are known to be involved in the pathogenesis of this disorder, yet we do not know if there is a common molecular mechanism. As mutations in the GABAergic receptor subunit gene GABRA4 are reported in patients with ASD, we eliminated the Gabra4 gene in mice and found that the Gabra4 knockout mice showed autistic-like behavior, enhanced spatial memory, and attenuated susceptibility to pentylenetetrazol-induced seizures, a constellation of symptoms resembling human high-functioning autism. To search for potential molecular pathways involved in these phenotypes, we performed a hippocampal transcriptome profiling, constructed a hippocampal interactome network, and revealed an upregulation of the NMDAR system at the center of the converged pathways underlying high-functioning autism-like and anti-epilepsy phenotypes.
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Affiliation(s)
- Cuixia Fan
- Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.,Institute of Neuroscience and Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China
| | - Yue Gao
- Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.,Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, 510515, China.,Department of Bioinformatics, School of Basic Medical Sciences, Southern Medical University, 1838 N. Guangzhou Ave, Guangzhou, 510515, China
| | - Guanmei Liang
- Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.,Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, 510515, China.,Department of Bioinformatics, School of Basic Medical Sciences, Southern Medical University, 1838 N. Guangzhou Ave, Guangzhou, 510515, China
| | - Lang Huang
- Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, 510515, China.,State Key Laboratory of Organ Failure Research, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Jing Wang
- Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Xiaoxue Yang
- Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Yiwu Shi
- Institute of Neuroscience and Department of Neurology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China
| | - Ursula C Dräger
- Department of Psychiatry, University of Massachusetts Medical School, Worcester, MA, 01655, USA
| | - Mei Zhong
- Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Tian-Ming Gao
- Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, 510515, China.,State Key Laboratory of Organ Failure Research, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Xinping Yang
- Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China. .,Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, 510515, China. .,Department of Bioinformatics, School of Basic Medical Sciences, Southern Medical University, 1838 N. Guangzhou Ave, Guangzhou, 510515, China.
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21
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van Loo KMJ, Becker AJ. Transcriptional Regulation of Channelopathies in Genetic and Acquired Epilepsies. Front Cell Neurosci 2020; 13:587. [PMID: 31992970 PMCID: PMC6971179 DOI: 10.3389/fncel.2019.00587] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 12/23/2019] [Indexed: 01/03/2023] Open
Abstract
Epilepsy is a common neurological disorder characterized by recurrent uncontrolled seizures and has an idiopathic “genetic” etiology or a symptomatic “acquired” component. Genetic studies have revealed that many epilepsy susceptibility genes encode ion channels, including voltage-gated sodium, potassium and calcium channels. The high prevalence of ion channels in epilepsy pathogenesis led to the causative concept of “ion channelopathies,” which can be elicited by specific mutations in the coding or promoter regions of genes in genetic epilepsies. Intriguingly, expression changes of the same ion channel genes by augmentation of specific transcription factors (TFs) early after an insult can underlie acquired epilepsies. In this study, we review how the transcriptional regulation of ion channels in both genetic and acquired epilepsies can be controlled, and compare these epilepsy “ion channelopathies” with other neurodevelopmental disorders.
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Affiliation(s)
- Karen M J van Loo
- Department of Neuropathology, Section for Translational Epilepsy Research, University of Bonn Medical Center, Bonn, Germany
| | - Albert J Becker
- Department of Neuropathology, Section for Translational Epilepsy Research, University of Bonn Medical Center, Bonn, Germany
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22
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Kuo SH, Louis ED, Faust PL, Handforth A, Chang SY, Avlar B, Lang EJ, Pan MK, Miterko LN, Brown AM, Sillitoe RV, Anderson CJ, Pulst SM, Gallagher MJ, Lyman KA, Chetkovich DM, Clark LN, Tio M, Tan EK, Elble RJ. Current Opinions and Consensus for Studying Tremor in Animal Models. CEREBELLUM (LONDON, ENGLAND) 2019; 18:1036-1063. [PMID: 31124049 PMCID: PMC6872927 DOI: 10.1007/s12311-019-01037-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Tremor is the most common movement disorder; however, we are just beginning to understand the brain circuitry that generates tremor. Various neuroimaging, neuropathological, and physiological studies in human tremor disorders have been performed to further our knowledge of tremor. But, the causal relationship between these observations and tremor is usually difficult to establish and detailed mechanisms are not sufficiently studied. To overcome these obstacles, animal models can provide an important means to look into human tremor disorders. In this manuscript, we will discuss the use of different species of animals (mice, rats, fruit flies, pigs, and monkeys) to model human tremor disorders. Several ways to manipulate the brain circuitry and physiology in these animal models (pharmacology, genetics, and lesioning) will also be discussed. Finally, we will discuss how these animal models can help us to gain knowledge of the pathophysiology of human tremor disorders, which could serve as a platform towards developing novel therapies for tremor.
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Affiliation(s)
- Sheng-Han Kuo
- Department of Neurology, Columbia University, 650 West 168th Street, Room 305, New York, NY, 10032, USA.
| | - Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, 800 Howard Avenue, Ste Lower Level, New Haven, CT, 06519, USA.
- Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA.
- Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT, USA.
| | - Phyllis L Faust
- Department of Pathology and Cell Biology, Columbia University Medical Center and the New York Presbyterian Hospital, New York, NY, USA
| | - Adrian Handforth
- Neurology Service, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Su-Youne Chang
- Department of Neurologic Surgery and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Billur Avlar
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
| | - Eric J Lang
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
| | - Ming-Kai Pan
- Department of Medical Research and Neurology, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Lauren N Miterko
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, TX, USA
| | - Amanda M Brown
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Roy V Sillitoe
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Collin J Anderson
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | | | - Kyle A Lyman
- Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Lorraine N Clark
- Department of Pathology and Cell Biology, Columbia University Medical Center and the New York Presbyterian Hospital, New York, NY, USA
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Murni Tio
- Department of Neurology, National Neuroscience Institute, Singapore, Singapore
- Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Eng-King Tan
- Department of Neurology, National Neuroscience Institute, Singapore, Singapore
- Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, USA
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23
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Anticonvulsant Effects of Dingxian Pill in Pentylenetetrazol-Kindled Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2019; 2019:4534167. [PMID: 31011358 PMCID: PMC6442303 DOI: 10.1155/2019/4534167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 02/24/2019] [Indexed: 12/24/2022]
Abstract
Dingxian pill has been used as an antiepilepsy agent in China from ancient to modern times, of which the concrete pharmacological characterization and the underlying molecular mechanism remain unclear. The present study was undertaken to investigate them by animal behavior, electroencephalogram (EEG), Morris water maze, immunohistochemistry, transcriptomics, and real-time PCR. In our results, the treatment of Dingxian pill dose-dependently inhibited PTZ-induced seizure-like behavior and reduced the seizure grades, LFP power spectral density, and brain wave of the epileptiform EEG component induced by PTZ. In Morris water maze tests, the learning and memory ability of kindled epileptic rats could be attenuated more efficiently by Dingxian pill. For the immediate early gene c-fos, the expression was reduced after Dingxian pill treatment, and the difference was significant between the treatment and the model group. Through the transcriptome analysis of the gene expression in hippocampus, Egr3, Nrg, Arc, and Ptgs2, closely related to epilepsy, had been proved to be downregulated by application of Dingxian pill. All of the results not only highlight the antiepileptic effects of Dingxian pill and its molecular mechanism, but also provide a modern validity theory for the clinical application of traditional Chinese medicine (TCM).
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24
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Keating N, Zeak N, Smith SS. Pubertal hormones increase hippocampal expression of α4βδ GABA A receptors. Neurosci Lett 2019; 701:65-70. [PMID: 30742936 DOI: 10.1016/j.neulet.2019.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/03/2019] [Accepted: 02/04/2019] [Indexed: 12/13/2022]
Abstract
CA1 hippocampal expression of α4βδ GABAA receptors (GABARs) increases at the onset of puberty in female mice, an effect dependent upon the decline in hippocampal levels of the neurosteroid THP (3α-OH-5α-pregnan-20-one) which occurs at this time. The present study further characterized the mechanisms underlying α4βδ expression, assessed in vivo. Blockade of pubertal levels of 17β-estradiol (E2) (formestane, 0.5 mg/kg, i.p. 3 d) reduced α4 and δ expression by 75-80% (P < 0.05) in CA1 hippocampus of female mice, assessed using Western blot techniques. Conversely, E2 administration increased α4 and δ expression by 50-100% in adults, an effect enhanced by more than 2-fold by concomitant administration of the 5α-reductase blocker finasteride (50 mg/kg, i.p., 3d, P < 0.05), suggesting that both declining THP levels and increasing E2 levels before puberty trigger α4βδ expression. This effect was blocked by ICI 182,780 (20 mg/kg, s.c., 3 d), a selective blocker of E2 receptor-α (ER-α). These results suggest that both the rise in circulating levels of E2 and the decline in hippocampal THP levels at the onset of puberty trigger maximal levels of α4βδ expression in the CA1 hippocampus.
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Affiliation(s)
- Nicole Keating
- Department of Physiology and Pharmacology, SUNY Downstate Medical Center, 450 Clarkson Ave., Brooklyn, NY, 11203, USA
| | - Nicole Zeak
- Department of Physiology and Pharmacology, SUNY Downstate Medical Center, 450 Clarkson Ave., Brooklyn, NY, 11203, USA
| | - Sheryl S Smith
- Department of Physiology and Pharmacology, SUNY Downstate Medical Center, 450 Clarkson Ave., Brooklyn, NY, 11203, USA.
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25
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Immediate-Early Promoter-Driven Transgenic Reporter System for Neuroethological Research in a Hemimetabolous Insect. eNeuro 2018; 5:eN-MNT-0061-18. [PMID: 30225346 PMCID: PMC6140108 DOI: 10.1523/eneuro.0061-18.2018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 07/11/2018] [Accepted: 07/20/2018] [Indexed: 01/04/2023] Open
Abstract
Genes expressed in response to increased neuronal activity are widely used as activity markers in recent behavioral neuroscience. In the present study, we established transgenic reporter system for whole-brain activity mapping in the two-spotted cricket Gryllus bimaculatus, a hemimetabolous insect used in neuroethology and behavioral ecology. In the cricket brain, a homolog of early growth response-1 (Gryllus egr-B) was rapidly induced as an immediate-early gene (IEG) in response to neuronal hyperexcitability. The upstream genomic fragment of Gryllus egr-B contains potential binding sites for transcription factors regulated by various intracellular signaling pathways, as well as core promoter elements conserved across insect/crustacean egr-B homologs. Using the upstream genomic fragment of Gryllus egr-B, we established an IEG promoter-driven transgenic reporter system in the cricket. In the brain of transgenic crickets, the reporter gene (a nuclear-targeted destabilized EYFP) was induced in response to neuronal hyperexcitability. Inducible expression of reporter protein was detected in almost all neurons after neuronal hyperexcitability. Using our novel reporter system, we successfully detected neuronal activation evoked by feeding in the cricket brain. Our IEG promoter-driven activity reporting system allows us to visualize behaviorally relevant neural circuits at cellular resolution in the cricket brain.
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26
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Gravielle MC. Regulation of GABAA receptors by prolonged exposure to endogenous and exogenous ligands. Neurochem Int 2018; 118:96-104. [DOI: 10.1016/j.neuint.2018.05.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 05/22/2018] [Accepted: 05/30/2018] [Indexed: 02/08/2023]
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27
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Meyers KT, Marballi KK, Brunwasser SJ, Renda B, Charbel M, Marrone DF, Gallitano AL. The Immediate Early Gene Egr3 Is Required for Hippocampal Induction of Bdnf by Electroconvulsive Stimulation. Front Behav Neurosci 2018; 12:92. [PMID: 29867393 PMCID: PMC5958205 DOI: 10.3389/fnbeh.2018.00092] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 04/23/2018] [Indexed: 01/19/2023] Open
Abstract
Early growth response 3 (Egr3) is an immediate early gene (IEG) that is regulated downstream of a cascade of genes associated with risk for psychiatric disorders, and dysfunction of Egr3 itself has been implicated in schizophrenia, bipolar disorder, and depression. As an activity-dependent transcription factor, EGR3 is poised to regulate the neuronal expression of target genes in response to environmental events. In the current study, we sought to identify a downstream target of EGR3 with the goal of further elucidating genes in this biological pathway relevant for psychiatric illness risk. We used electroconvulsive stimulation (ECS) to induce high-level expression of IEGs in the brain, and conducted expression microarray to identify genes differentially regulated in the hippocampus of Egr3-deficient (-/-) mice compared to their wildtype (WT) littermates. Our results replicated previous work showing that ECS induces high-level expression of the brain-derived neurotrophic factor (Bdnf) in the hippocampus of WT mice. However, we found that this induction is absent in Egr3-/- mice. Quantitative real-time PCR (qRT-PCR) validated the microarray results (performed in males) and replicated the findings in two separate cohorts of female mice. Follow-up studies of activity-dependent Bdnf exons demonstrated that ECS-induced expression of both exons IV and VI requires Egr3. In situ hybridization demonstrated high-level cellular expression of Bdnf in the hippocampal dentate gyrus following ECS in WT, but not Egr3-/-, mice. Bdnf promoter analysis revealed eight putative EGR3 binding sites in the Bdnf promoter, suggesting a mechanism through which EGR3 may directly regulate Bdnf gene expression. These findings do not appear to result from a defect in the development of hippocampal neurons in Egr3-/- mice, as cell counts in tissue sections stained with anti-NeuN antibodies, a neuron-specific marker, did not differ between Egr3-/- and WT mice. In addition, Sholl analysis and counts of dendritic spines in golgi-stained hippocampal sections revealed no difference in dendritic morphology or synaptic spine density in Egr3-/-, compared to WT, mice. These findings indicate that Egr3 is required for ECS-induced expression of Bdnf in the hippocampus and suggest that Bdnf may be a downstream gene in our previously identified biologically pathway for psychiatric illness susceptibility.
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Affiliation(s)
- Kimberly T Meyers
- Department of Basic Medical Sciences, College of Medicine Phoenix, University of Arizona, Phoenix, AZ, United States.,Interdisciplinary Graduate Program in Neuroscience, Arizona State University, Tempe, AZ, United States
| | - Ketan K Marballi
- Department of Basic Medical Sciences, College of Medicine Phoenix, University of Arizona, Phoenix, AZ, United States
| | - Samuel J Brunwasser
- Department of Basic Medical Sciences, College of Medicine Phoenix, University of Arizona, Phoenix, AZ, United States.,Medical Scientist Training Program, School of Medicine, Washington University in St. Louis, St. Louis, MO, United States
| | - Briana Renda
- Department of Psychology, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Milad Charbel
- Department of Basic Medical Sciences, College of Medicine Phoenix, University of Arizona, Phoenix, AZ, United States.,Barrett, The Honors college, Arizona State University, Tempe, AZ, United States
| | - Diano F Marrone
- Department of Psychology, Wilfrid Laurier University, Waterloo, ON, Canada.,Evelyn F. McKnight Brain Institute, The University of Arizona, Tucson, AZ, United States
| | - Amelia L Gallitano
- Department of Basic Medical Sciences, College of Medicine Phoenix, University of Arizona, Phoenix, AZ, United States
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28
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Lorenz-Guertin JM, Jacob TC. GABA type a receptor trafficking and the architecture of synaptic inhibition. Dev Neurobiol 2018; 78:238-270. [PMID: 28901728 PMCID: PMC6589839 DOI: 10.1002/dneu.22536] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/08/2017] [Accepted: 09/08/2017] [Indexed: 12/21/2022]
Abstract
Ubiquitous expression of GABA type A receptors (GABAA R) in the central nervous system establishes their central role in coordinating most aspects of neural function and development. Dysregulation of GABAergic neurotransmission manifests in a number of human health disorders and conditions that in certain cases can be alleviated by drugs targeting these receptors. Precise changes in the quantity or activity of GABAA Rs localized at the cell surface and at GABAergic postsynaptic sites directly impact the strength of inhibition. The molecular mechanisms constituting receptor trafficking to and from these compartments therefore dictate the efficacy of GABAA R function. Here we review the current understanding of how GABAA Rs traffic through biogenesis, plasma membrane transport, and degradation. Emphasis is placed on discussing novel GABAergic synaptic proteins, receptor and scaffolding post-translational modifications, activity-dependent changes in GABAA R confinement, and neuropeptide and neurosteroid mediated changes. We further highlight modern techniques currently advancing the knowledge of GABAA R trafficking and clinically relevant neurodevelopmental diseases connected to GABAergic dysfunction. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 238-270, 2018.
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Affiliation(s)
- Joshua M Lorenz-Guertin
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, 15261
| | - Tija C Jacob
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, 15261
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29
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Developmental Disruption of GABA AR-Meditated Inhibition in Cntnap2 KO Mice. eNeuro 2017; 4:eN-NWR-0162-17. [PMID: 28966979 PMCID: PMC5617210 DOI: 10.1523/eneuro.0162-17.2017] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 12/24/2022] Open
Abstract
GABA released from presynaptic sites induces short-lived phasic inhibition mediated by synaptic GABAA receptors (GABAARs) and longer-duration tonic inhibition mediated by extrasynaptic GABAA or GABAB receptors (GABABRs). A number of studies have found that contactin-associated protein 2 (Cntnap2) knockout (KO) mice, a well-established mouse model of autism, exhibit reduced interneuron numbers and aberrant phasic inhibition. However, little is known about whether tonic inhibition is disrupted in Cntnap2 KO mice and when the disruption of inhibition begins to occur during postnatal development. We examined tonic and phasic inhibition in layer 2/3 pyramidal cells of primary visual cortex of Cntnap2 KO at two different developmental stages, three to four and six to eight weeks of age. We found that both phasic inhibition and GABAAR but not GABABR-mediated tonic inhibition was reduced in pyramidal cells from six- to eight-week-old Cntnap2 KO mice, while in three- to four-week-old mice, no significant effects of genotype on tonic or phasic inhibition was observed. We further found that activation of tonic currents mediated by δ-subunit-containing GABAARs reduced neural excitability, an effect that was attenuated by loss of Cntnap2. While the relative contribution of tonic versus phasic inhibition to autism-related symptoms remains unclear, our data suggest that reduced tonic inhibition may play an important role, and δ-subunit-containing GABAARs may be a useful target for therapeutic intervention in autism.
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30
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López-López D, Gómez-Nieto R, Herrero-Turrión MJ, García-Cairasco N, Sánchez-Benito D, Ludeña MD, López DE. Overexpression of the immediate-early genes Egr1, Egr2, and Egr3 in two strains of rodents susceptible to audiogenic seizures. Epilepsy Behav 2017; 71:226-237. [PMID: 26775236 DOI: 10.1016/j.yebeh.2015.12.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 12/10/2015] [Accepted: 12/12/2015] [Indexed: 11/17/2022]
Abstract
Genetic animal models of epilepsy are an important tool for further understanding the basic cellular mechanisms underlying epileptogenesis and for developing novel antiepileptic drugs. We conducted a comparative study of gene expression in the inferior colliculus, a nucleus that triggers audiogenic seizures, using two animal models, the Wistar audiogenic rat (WAR) and the genetic audiogenic seizure hamster (GASH:Sal). For this purpose, both models were exposed to high intensity auditory stimulation, and 60min later, the inferior colliculi were collected. As controls, intact Wistar rats and Syrian hamsters were subjected to stimulation and tissue preparation protocols identical to those performed on the experimental animals. Ribonucleic acid was isolated, and microarray analysis comparing the stimulated Wistar and WAR rats showed that the genomic profile of these animals displayed significant (fold change, |FC|≥2.0 and p<0.05) upregulation of 38 genes and downregulation of 47 genes. Comparison of gene expression profiles between stimulated control hamsters and stimulated GASH:Sal revealed the upregulation of 10 genes and the downregulation of 5 genes. Among the common genes that were altered in both models, we identified the zinc finger immediate-early growth response gene Egr3. The Egr3 protein is a transcription factor that is induced by distinct stress-elicited factors. Based on immunohistochemistry, this protein was expressed in the cochlear nucleus complex, the inferior colliculus, and the hippocampus of both animal models as well as in lymphoma tumors of the GASH:Sal. Our results support that the overexpression of the Egr3 gene in both models might contribute to neuronal viability and development of lymphoma in response to stress associated with audiogenic seizures. This article is part of a Special Issue entitled "Genetic and Reflex Epilepsies, Audiogenic Seizures and Strains: From Experimental Models to the Clinic".
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Affiliation(s)
- D López-López
- Institute for Neuroscience of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain; Salamanca Institute for Biomedical Research (IBSAL), Spain
| | - R Gómez-Nieto
- Institute for Neuroscience of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain; Salamanca Institute for Biomedical Research (IBSAL), Spain; Department of Cell Biology and Pathology, School of Medicine, University of Salamanca, Salamanca, Spain
| | - M J Herrero-Turrión
- Institute for Neuroscience of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain
| | - N García-Cairasco
- Physiology Department, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, Brazil
| | - D Sánchez-Benito
- Institute for Neuroscience of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain; Salamanca Institute for Biomedical Research (IBSAL), Spain
| | - M D Ludeña
- Department of Cell Biology and Pathology, School of Medicine, University of Salamanca, Salamanca, Spain
| | - D E López
- Institute for Neuroscience of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain; Salamanca Institute for Biomedical Research (IBSAL), Spain; Department of Cell Biology and Pathology, School of Medicine, University of Salamanca, Salamanca, Spain.
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31
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Manning CE, Williams ES, Robison AJ. Reward Network Immediate Early Gene Expression in Mood Disorders. Front Behav Neurosci 2017; 11:77. [PMID: 28503137 PMCID: PMC5408019 DOI: 10.3389/fnbeh.2017.00077] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 04/11/2017] [Indexed: 12/30/2022] Open
Abstract
Over the past three decades, it has become clear that aberrant function of the network of interconnected brain regions responsible for reward processing and motivated behavior underlies a variety of mood disorders, including depression and anxiety. It is also clear that stress-induced changes in reward network activity underlying both normal and pathological behavior also cause changes in gene expression. Here, we attempt to define the reward circuitry and explore the known and potential contributions of activity-dependent changes in gene expression within this circuitry to stress-induced changes in behavior related to mood disorders, and contrast some of these effects with those induced by exposure to drugs of abuse. We focus on a series of immediate early genes regulated by stress within this circuitry and their connections, both well-explored and relatively novel, to circuit function and subsequent reward-related behaviors. We conclude that IEGs play a crucial role in stress-dependent remodeling of reward circuitry, and that they may serve as inroads to the molecular, cellular, and circuit-level mechanisms of mood disorder etiology and treatment.
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Affiliation(s)
- Claire E Manning
- Department of Physiology, Michigan State UniversityEast Lansing, MI, USA
| | | | - Alfred J Robison
- Department of Physiology, Michigan State UniversityEast Lansing, MI, USA
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32
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Yu W, Du Y, Zou Y, Wang X, Stephani U, Lü Y. Smad anchor for receptor activation contributes to seizures in temporal lobe epilepsy. Synapse 2017; 71. [PMID: 28035691 DOI: 10.1002/syn.21957] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 12/19/2016] [Accepted: 12/25/2016] [Indexed: 11/07/2022]
Abstract
PURPOSE Smad anchor for receptor activation (SARA) is an important regulator of transforming growth factor β (TGF-β) signaling by recruiting Smad2/3 to TGF-β receptors. Although TGF-β signaling is critically involved in epileptogenesis, whether SARA activation is sufficient to facilitate TGF-β pathway to regulate epilepsy remains unknown. METHODS The expression of SARA and downstream Phospho-Smad3 (p-Smad3) was examined in rats with pilocarpine induced epilepsy. Additionally, knockdown of SARA was performed via recombinant lentiviral vector in the pilocarpine-induced rats. RESULTS Here we show that expressions of SARA and p-Smad3 are increased in the hippocampus as rats subjected to pilocarpine-induced status epilepticus (SE). Both SARA and p-Smad3 are also upregulated in the temporal cortex of epileptic rats. Furthermore, SARA mRNA levels reach peak as early as 6 hr following SE onset and remain elevated in the chronic phase. Transfection of recombinant lentiviral shRNA targeting SARA knocks down SARA expression, attenuates TGF-β/p-Smad3 signaling in the hippocampus, and postpones the SE onset. CONCLUSION Our results demonstrate that SARA/Smad3 pathway contributes to mechanism of seizure and SARA in TGF-β signaling may be a potential therapeutic target for epilepsy.
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Affiliation(s)
- Weihua Yu
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China.,Institutes of Neuroscience, Chongqing Medical University, Chongqing, 400016, China
| | - Yingshi Du
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Yan Zou
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Xuefeng Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Ulrich Stephani
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Kiel, 24105, Germany
| | - Yang Lü
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
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33
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Kim J, Lee S, Kang S, Kim SH, Kim JC, Yang M, Moon C. Brain-derived neurotropic factor and GABAergic transmission in neurodegeneration and neuroregeneration. Neural Regen Res 2017; 12:1733-1741. [PMID: 29171440 PMCID: PMC5696856 DOI: 10.4103/1673-5374.217353] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Neurotoxicity induced by stress, radiation, chemicals, or metabolic diseases, is commonly associated with excitotoxicity, oxidative stress, and neuroinflammation. The pathological process of neurotoxicity induces neuronal death, interrupts synaptic plasticity in the brain, and is similar to that of diverse neurodegenerative diseases. Animal models of neurotoxicity have revealed that clinical symptoms and brain lesions can recover over time via neuroregenerative processes. Specifically, brain-derived neurotropic factor (BDNF) and gamma-aminobutyric acid (GABA)-ergic transmission are related to both neurodegeneration and neuroregeneration. This review summarizes the accumulating evidences that suggest a pathogenic role of BDNF and GABAergic transmission, their underlying mechanisms, and the relationship between BDNF and GABA in neurodegeneration and neuroregeneration. This review will provide a comprehensive overview of the underlying mechanisms of neuroregeneration that may help in developing potential strategies for pharmacotherapeutic approaches to treat neurotoxicity and neurodegenerative disease.
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Affiliation(s)
- Jinwook Kim
- Departments of Veterinary Anatomy and Veterinary Toxicology, College of Veterinary Medicine and BK21 PLUS Project Team, Chonnam National University, Gwangju, South Korea
| | - Sueun Lee
- Departments of Veterinary Anatomy and Veterinary Toxicology, College of Veterinary Medicine and BK21 PLUS Project Team, Chonnam National University, Gwangju, South Korea
| | - Sohi Kang
- Departments of Veterinary Anatomy and Veterinary Toxicology, College of Veterinary Medicine and BK21 PLUS Project Team, Chonnam National University, Gwangju, South Korea
| | - Sung-Ho Kim
- Departments of Veterinary Anatomy and Veterinary Toxicology, College of Veterinary Medicine and BK21 PLUS Project Team, Chonnam National University, Gwangju, South Korea
| | - Jong-Choon Kim
- Departments of Veterinary Anatomy and Veterinary Toxicology, College of Veterinary Medicine and BK21 PLUS Project Team, Chonnam National University, Gwangju, South Korea
| | - Miyoung Yang
- Department of Anatomy, School of Medicine and Institute for Environmental Science, Wonkwang University, Jeonbuk, South Korea
| | - Changjong Moon
- Departments of Veterinary Anatomy and Veterinary Toxicology, College of Veterinary Medicine and BK21 PLUS Project Team, Chonnam National University, Gwangju, South Korea
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Grønli J, Clegern WC, Schmidt MA, Nemri RS, Rempe MJ, Gallitano AL, Wisor JP. Sleep Homeostatic and Waking Behavioral Phenotypes in Egr3-Deficient Mice Associated with Serotonin Receptor 5-HT 2 Deficits. Sleep 2016; 39:2189-2199. [PMID: 28057087 DOI: 10.5665/sleep.6324] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 08/01/2016] [Indexed: 02/06/2023] Open
Abstract
STUDY OBJECTIVE The expression of the immediate early gene early growth response 3 (Egr3) is a functional marker of brain activity including responses to novelty, sustained wakefulness, and sleep. We examined the role of this gene in regulating wakefulness and sleep. METHODS Electroencephalogram/electromyogram (EEG/EMG) were recorded in Egr3-/- and wild-type (WT) mice during 24 h baseline, 6 h sleep disruption and 6 h recovery. Serotonergic signaling was assessed with 6 h EEG/EMG recordings after injections of nonselective 5-HT2 antagonist (clozapine), selective 5-HT2 antagonists (5-HT2A; MDL100907 and 5-HT2BC; SB206553) and a cocktail of both selective antagonists, administered in a randomized order to each animal. RESULTS Egr3-/- mice did not exhibit abnormalities in the timing of wakefulness and slow wave sleep (SWS); however, EEG dynamics in SWS (suppressed 1-3 Hz power) and in quiet wakefulness (elevated 3-8 Hz and 15-35 Hz power) differed in comparison to WT-mice. Egr3-/- mice showed an exaggerated response to sleep disruption as measured by active wakefulness, but with a blunted increase in homeostatic sleep drive (elevated 1-4 Hz power) relative to WT-mice. Egr3-/-mice exhibit greatly reduced sedative effects of clozapine at the electroencephalographic level. In addition, clozapine induced a previously undescribed dissociated state (low amplitude, low frequency EEG and a stable, low muscle tone) lasting up to 2 h in WT-mice. Egr3-/- mice did not exhibit this phenomenon. Selective 5-HT2A antagonist, alone or in combination with selective 5-HT2BC antagonist, caused EEG slowing coincident with behavioral quiescence in WT-mice but not in Egr3-/- mice. CONCLUSION Egr3 has an essential role in regulating cortical arousal, wakefulness, and sleep, presumably by its regulation of 5-HT2 receptors.
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Affiliation(s)
- Janne Grønli
- Elson S. Floyd College of Medicine, Department of Biomedical Sciences, Washington State University, Spokane, WA.,Sleep and Performance Research Center, Washington State University.,Department of Biological and Medical Psychology, University of Bergen, Norway
| | - William C Clegern
- Elson S. Floyd College of Medicine, Department of Biomedical Sciences, Washington State University, Spokane, WA
| | - Michelle A Schmidt
- Elson S. Floyd College of Medicine, Department of Biomedical Sciences, Washington State University, Spokane, WA
| | - Rahmi S Nemri
- Elson S. Floyd College of Medicine, Department of Biomedical Sciences, Washington State University, Spokane, WA
| | - Michael J Rempe
- Sleep and Performance Research Center, Washington State University.,Mathematics and Computer Science, Whitworth University, Spokane, WA
| | - Amelia L Gallitano
- Department of Basic Medical Sciences and Psychiatry, University of Arizona College of Medicine-Phoenix, Phoenix, AZ
| | - Jonathan P Wisor
- Elson S. Floyd College of Medicine, Department of Biomedical Sciences, Washington State University, Spokane, WA.,Sleep and Performance Research Center, Washington State University
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Abstract
Tonic inhibition mediated by extrasynaptic GABA(A) receptors (GABARs) sensing ambient levels of GABA can profoundly alter the membrane input resistance to affect cellular excitability. Therefore, regulation of tonic inhibition is an attractive mechanism to control the levels of cortical firing. In cortical pyramidal cells, tonic inhibition is regulated by age and several neurotransmitters and is affected by stroke and epilepsy. However, the possible role of sensory experience has not been examined. Here, we report that a brief 2-day exposure to dark reduces by 1/3 the inhibitory tonic conductance recorded in layer II/III pyramidal cells of the mouse juvenile (postnatal day 12-27) visual cortex. In these cells, tonic inhibition is carried primarily by GABARs containing the δ subunit. Consistently, the dark exposure reduction in conductance was associated with a reduction in δ subunit levels, which were not affected in control frontal cortex. We propose that a deprivation-induced reduction in tonic inhibition might serve a homeostatic function by increasing the firing levels of cells in deprived cortical circuits.
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Farb DH, Ratner MH. Targeting the modulation of neural circuitry for the treatment of anxiety disorders. Pharmacol Rev 2015; 66:1002-32. [PMID: 25237115 DOI: 10.1124/pr.114.009126] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Anxiety disorders are a major public health concern. Here, we examine the familiar area of anxiolysis in the context of a systems-level understanding that will hopefully lead to revealing an underlying pharmacological connectome. The introduction of benzodiazepines nearly half a century ago markedly improved the treatment of anxiety disorders. These agents reduce anxiety rapidly by allosterically enhancing the postsynaptic actions of GABA at inhibitory type A GABA receptors but side effects limit their use in chronic anxiety disorders. Selective serotonin reuptake inhibitors and serotonin/norepinephrine reuptake inhibitors have emerged as an effective first-line alternative treatment of such anxiety disorders. However, many individuals are not responsive and side effects can be limiting. Research into a relatively new class of agents known as neurosteroids has revealed novel modulatory sites and mechanisms of action that are providing insights into the pathophysiology of certain anxiety disorders, potentially bridging the gap between the GABAergic and serotonergic circuits underlying anxiety. However, translating the pharmacological activity of compounds targeted to specific receptor subtypes in rodent models of anxiety to effective therapeutics in human anxiety has not been entirely successful. Since modulating any one of several broad classes of receptor targets can produce anxiolysis, we posit that a systems-level discovery platform combined with an individualized medicine approach based on noninvasive brain imaging would substantially advance the development of more effective therapeutics.
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Affiliation(s)
- David H Farb
- Laboratory of Molecular Neurobiology, Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts
| | - Marcia H Ratner
- Laboratory of Molecular Neurobiology, Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts
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Mo J, Kim CH, Lee D, Sun W, Lee HW, Kim H. Early growth response 1 (Egr-1) directly regulates GABAA receptor α2, α4, and θ subunits in the hippocampus. J Neurochem 2015; 133:489-500. [PMID: 25708312 DOI: 10.1111/jnc.13077] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 02/10/2015] [Accepted: 02/17/2015] [Indexed: 11/28/2022]
Abstract
The homeostatic regulation of neuronal activity in glutamatergic and GABAergic synapses is critical for neural circuit development and synaptic plasticity. The induced expression of the transcription factor early growth response 1 (Egr-1) in neurons is tightly associated with many forms of neuronal activity, but the underlying target genes in the brain remained to be elucidated. This study uses a quantitative real-time PCR approach, in combination with in vivo chromatin immunoprecipitation, and reveals that GABAA receptor subunit, GABRA2 (α2), GABRA4 (α4), and GABRQ (θ) genes, are transcriptional targets of Egr-1. Transfection of a construct that over-expresses Egr-1 in neuroblastoma (Neuro2A) cells up-regulates the α2, α4, and θ subunits. Given that Egr-1 knockout mice display less GABRA2, GABRA4, and GRBRQ mRNA in the hippocampus, and that Egr-1 directly binds to their promoters and induces mRNA expression, the present findings support a role for Egr-1 as a major regulator for altered GABAA receptor composition in homeostatic plasticity, in a glutamatergic activity-dependent manner. The early growth response 1 (Egr-1) is an inducible transcription factor to mediate rapid gene expression by neuronal activity. However, its underlying molecular target genes and mechanisms are not fully understood. We suggest that GABAA receptor subunits, GABRA2 (α2), GABRA4 (α4), and GABRQ (θ) genes are transcriptional targets of Egr-1. Neuronal activity-dependent up-regulation of Egr-1 might lead to altered subtypes of GABAA receptors for the maintenance of homeostatic excitatory and inhibitory balance for the regulation of synaptic strength.
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Affiliation(s)
- Jiwon Mo
- Department of Anatomy and Division of Brain Korea 21 Biomedical Science, College of Medicine, Korea University, Seoul, Korea
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Grabenstatter HL, Cogswell M, Cruz Del Angel Y, Carlsen J, Gonzalez MI, Raol YH, Russek SJ, Brooks-Kayal AR. Effect of spontaneous seizures on GABAA receptor α4 subunit expression in an animal model of temporal lobe epilepsy. Epilepsia 2014; 55:1826-33. [PMID: 25223733 DOI: 10.1111/epi.12771] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/31/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Temporal lobe epilepsy (TLE) is frequently medically intractable and often progressive. Compromised inhibitory neurotransmission due to altered γ-aminobutyric acid (GABA)A receptor α4 subunit (GABAA Rα4) expression has been emphasized as a potential contributor to the initial development of epilepsy following a brain insult (primary epileptogenesis), but the regulation of GABAA Rα4 during chronic epilepsy, specifically, how expression is altered following spontaneous seizures, is less well understood. METHODS Continuous video-electroencephalography (EEG) recordings from rats with pilocarpine-induced TLE were used to capture epileptic animals within 3 h of a spontaneous seizure (SS), or >24 h after the last SS, to determine whether recent occurrence of a seizure was associated with altered levels of GABAA Rα4 expression. We further evaluated whether this GABAA Rα4 plasticity is regulated by signaling mechanisms active in primary epileptogenesis, specifically, increases in brain-derived neurotrophic factor (BDNF) and early growth response factor 3 (Egr3). RESULTS Elevated levels of GABAA Rα4 messenger RNA (mRNA) and protein were observed following spontaneous seizures, and were associated with higher levels of BDNF and Egr3 mRNA. SIGNIFICANCE These data suggest that spontaneous, recurrent seizures that define chronic epilepsy may influence changes in GABAA Rα4 expression, and that signaling pathways known to regulate GABAA Rα4 expression after status epilepticus may also be activated after spontaneous seizures in chronically epileptic animals.
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Affiliation(s)
- Heidi L Grabenstatter
- Department of Pediatrics, Section of Neurology, Translational Epilepsy Research Program, University of Colorado, AMC, Aurora, Colorado, U.S.A
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Modulation of GABAA receptor signaling increases neurogenesis and suppresses anxiety through NFATc4. J Neurosci 2014; 34:8630-45. [PMID: 24948817 DOI: 10.1523/jneurosci.0047-14.2014] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Correlative evidence suggests that GABAergic signaling plays an important role in the regulation of activity-dependent hippocampal neurogenesis and emotional behavior in adult mice. However, whether these are causally linked at the molecular level remains elusive. Nuclear factor of activated T cell (NFAT) proteins are activity-dependent transcription factors that respond to environmental stimuli in different cell types, including hippocampal newborn neurons. Here, we identify NFATc4 as a key activity-dependent transcriptional regulator of GABA signaling in hippocampal progenitor cells via an unbiased high-throughput genome-wide study. Next, we demonstrate that GABAA receptor (GABAAR) signaling modulates hippocampal neurogenesis through NFATc4 activity, which in turn regulates GABRA2 and GABRA4 subunit expression via binding to specific promoter responsive elements, as assessed by ChIP and luciferase assays. Furthermore, we show that selective pharmacological enhancement of GABAAR activity promotes hippocampal neurogenesis via the calcineurin/NFATc4 axis. Importantly, the NFATc4-dependent increase in hippocampal neurogenesis after GABAAR stimulation is required for the suppression of the anxiety response in mice. Together, these data provide a novel molecular insight into the regulation of the anxiety response in mice, suggesting that the GABAAR/NFATc4 axis is a druggable target for the therapy of emotional disorders.
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Dihydromyricetin prevents fetal alcohol exposure-induced behavioral and physiological deficits: the roles of GABAA receptors in adolescence. Neurochem Res 2014; 39:1147-61. [PMID: 24676702 DOI: 10.1007/s11064-014-1291-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 03/18/2014] [Accepted: 03/20/2014] [Indexed: 10/25/2022]
Abstract
Fetal alcohol exposure (FAE) can lead to a variety of behavioral and physiological disturbances later in life. Understanding how alcohol (ethanol, EtOH) affects fetal brain development is essential to guide the development of better therapeutics for FAE. One of EtOH's many pharmacological targets is the γ-aminobutyric acid type A receptor (GABAAR), which plays a prominent role in early brain development. Acute EtOH potentiates inhibitory currents carried by certain GABAAR subtypes, whereas chronic EtOH leads to persistent alterations in GABAAR subunit composition, localization and function. We recently introduced a flavonoid compound, dihydromyricetin (DHM), which selectively antagonizes EtOH's intoxicating effects in vivo and in vitro at enhancing GABAAR function as a candidate for alcohol abuse pharmacotherapy. Here, we studied the effect of FAE on physiology, behavior and GABAAR function of early adolescent rats and tested the utility of DHM as a preventative treatment for FAE-induced disturbances. Gavage administration of EtOH (1.5, 2.5, or 5.0 g/kg) to rat dams on day 5, 8, 10, 12, and 15 of pregnancy dose-dependently reduced female/male offspring ratios (largely through decreased numbers of female offspring) and offspring body weights. FAE (2.5 g/kg) rats tested on postnatal days (P) 25-32 also exhibited increased anxiety and reduced pentylenetetrazol (PTZ)-induced seizure threshold. Patch-clamp recordings from dentate gyrus granule cells (DGCs) in hippocampal slices from FAE (2.5 g/kg) rats at P25-35 revealed reduced sensitivity of GABAergic miniature inhibitory postsynaptic currents (mIPSCs) and tonic current (Itonic) to potentiation by zolpidem (0.3 μM). Interestingly, potentiation of mIPSCs by gaboxadol increased, while potentiation of Itonic decreased in DGCs from FAE rats. Co-administration of EtOH (1.5 or 2.5 g/kg) with DHM (1.0 mg/kg) in pregnant dams prevented all of the behavioral, physiological, and pharmacological alterations observed in FAE offspring. DHM administration alone in pregnant rats had no adverse effect on litter size, progeny weight, anxiety level, PTZ seizure threshold, or DGC GABAAR function. Our results indicate that FAE induces long-lasting alterations in physiology, behavior, and hippocampal GABAAR function and that these deficits are prevented by DHM co-treatment of EtOH-exposed dams. The absence of adverse side effects and the ability of DHM to prevent FAE consequences suggest that DHM is an attractive candidate for development as a treatment for prevention of fetal alcohol spectrum disorders.
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Wehrspaun CC, Ponting CP, Marques AC. Brain-expressed 3'UTR extensions strengthen miRNA cross-talk between ion channel/transporter encoding mRNAs. Front Genet 2014; 5:41. [PMID: 24616735 PMCID: PMC3935148 DOI: 10.3389/fgene.2014.00041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 02/03/2014] [Indexed: 01/28/2023] Open
Abstract
Why protein-coding genes express transcripts with longer 3′untranslated regions (3′UTRs) in the brain rather than in other tissues remains poorly understood. Given the established role of 3′UTRs in post-transcriptional regulation of transcript abundance and their recently highlighted contributions to miRNA-mediated cross-talk between mRNAs, we hypothesized that 3′UTR lengthening enhances coordinated expression between functionally-related genes in the brain. To test this hypothesis, we annotated 3′UTRs of human brain-expressed genes and found that transcripts encoding ion channels or transporters are specifically enriched among those genes expressing their longest 3′UTR extension in this tissue. These 3′UTR extensions have high density of response elements predicted for those miRNAs that are specifically expressed in the human frontal cortex (FC). Importantly, these miRNA response elements are more frequently shared among ion channel/transporter-encoding mRNAs than expected by chance. This indicates that miRNA-mediated cross-talk accounts, at least in part, for the observed coordinated expression of ion channel/transporter genes in the adult human brain. We conclude that extension of these genes' 3′UTRs enhances the miRNA-mediated cross-talk among their transcripts which post-transcriptionally regulates their mRNAs' relative levels.
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Affiliation(s)
- Claudia C Wehrspaun
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK ; Section on Neuropathology, Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, IRP, NIMH, National Institutes of Health Bethesda, MD, USA
| | - Chris P Ponting
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK ; MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
| | - Ana C Marques
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK ; MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
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Dey D, Eckle VS, Vitko I, Sullivan KA, Lasiecka ZM, Winckler B, Stornetta RL, Williamson JM, Kapur J, Perez-Reyes E. A potassium leak channel silences hyperactive neurons and ameliorates status epilepticus. Epilepsia 2014; 55:203-13. [PMID: 24299204 PMCID: PMC4161023 DOI: 10.1111/epi.12472] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2013] [Indexed: 01/20/2023]
Abstract
OBJECTIVE To develop a constitutively active K(+) leak channel using TREK-1 (TWIK-related potassium channel 1; TREK-M) that is resistant to compensatory down-regulation by second messenger cascades, and to validate the ability of TREK-M to silence hyperactive neurons using cultured hippocampal neurons. To test if adenoassociated viral (AAV) delivery of TREK-M could reduce the duration of status epilepticus and reduce neuronal death induced by lithium-pilocarpine administration. METHODS Molecular cloning techniques were used to engineer novel vectors to deliver TREK-M via plasmids, lentivirus, and AAV using a cytomegalovirus (CMV)-enhanced GABRA4 promoter. Electrophysiology was used to characterize the activity and regulation of TREK-M in human embryonic kidney (HEK-293) cells, and the ability to reduce spontaneous activity in cultured hippocampal neurons. Adult male rats were injected bilaterally with self-complementary AAV particles composed of serotype 5 capsid into the hippocampus and entorhinal cortex. Lithium-pilocarpine was used to induce status epilepticus. Seizures were monitored using continuous video-electroencephalography (EEG) monitoring. Neuronal death was measured using Fluoro-Jade C staining of paraformaldehyde-fixed brain slices. RESULTS TREK-M inhibited neuronal firing by hyperpolarizing the resting membrane potential and decreasing input resistance. AAV delivery of TREK-M decreased the duration of status epilepticus by 50%. Concomitantly it reduced neuronal death in areas targeted by the AAV injection. SIGNIFICANCE These findings demonstrate that TREK-M can silence hyperexcitable neurons in the brain of epileptic rats and treat acute seizures. This study paves the way for an alternative gene therapy treatment of status epilepticus, and provides the rationale for studies of AAV-TREK-M's effect on spontaneous seizures in chronic models of temporal lobe epilepsy.
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Affiliation(s)
- Deblina Dey
- Departments of Pharmacology, Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
- Neuroscience Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
| | - Veit-Simon Eckle
- Departments of Pharmacology, Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
| | - Iuliia Vitko
- Departments of Pharmacology, Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
| | - Kyle A. Sullivan
- Departments of Pharmacology, Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
- Undergraduate School of Arts and Sciences, University of Virginia, Charlottesville, Virginia, U.S.A
| | - Zofia M. Lasiecka
- Department of Neuroscience, Virginia School of Medicine, Charlottesville, Virginia, U.S.A
| | - Bettina Winckler
- Neuroscience Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
- Department of Neuroscience, Virginia School of Medicine, Charlottesville, Virginia, U.S.A
| | - Ruth L. Stornetta
- Departments of Pharmacology, Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
| | - John M. Williamson
- Department of Neurology, Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
| | - Jaideep Kapur
- Neuroscience Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
- Department of Neurology, Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
| | - Edward Perez-Reyes
- Departments of Pharmacology, Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
- Neuroscience Graduate Program University of Virginia School of Medicine, Charlottesville, Virginia, U.S.A
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Scharfman HE, Brooks-Kayal AR. Is plasticity of GABAergic mechanisms relevant to epileptogenesis? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 813:133-50. [PMID: 25012373 DOI: 10.1007/978-94-017-8914-1_11] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Numerous changes in GABAergic neurons, receptors, and inhibitory mechanisms have been described in temporal lobe epilepsy (TLE), either in humans or in animal models. Nevertheless, there remains a common assumption that epilepsy can be explained by simply an insufficiency of GABAergic inhibition. Alternatively, investigators have suggested that there is hyperinhibition that masks an underlying hyperexcitability. Here we examine the status epilepticus (SE) models of TLE and focus on the dentate gyrus of the hippocampus, where a great deal of data have been collected. The types of GABAergic neurons and GABAA receptors are summarized under normal conditions and after SE. The role of GABA in development and in adult neurogenesis is discussed. We suggest that instead of "too little or too much" GABA there is a complexity of changes after SE that makes the emergence of chronic seizures (epileptogenesis) difficult to understand mechanistically, and difficult to treat. We also suggest that this complexity arises, at least in part, because of the remarkable plasticity of GABAergic neurons and GABAA receptors in response to insult or injury.
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Affiliation(s)
- Helen E Scharfman
- The Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, USA,
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Ferando I, Mody I. Altered gamma oscillations during pregnancy through loss of δ subunit-containing GABA(A) receptors on parvalbumin interneurons. Front Neural Circuits 2013; 7:144. [PMID: 24062647 PMCID: PMC3775147 DOI: 10.3389/fncir.2013.00144] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/27/2013] [Indexed: 11/26/2022] Open
Abstract
Gamma (γ) oscillations (30–120 Hz), an emergent property of neuronal networks, correlate with memory, cognition and encoding. In the hippocampal CA3 region, locally generated γ oscillations emerge through feedback between inhibitory parvalbumin-positive basket cells (PV+BCs) and the principal (pyramidal) cells. PV+BCs express δ-subunit-containing GABAARs (δ-GABAARs) and NMDA receptors (NMDA-Rs) that balance the frequency of γ oscillations. Neuroactive steroids (NS), such as the progesterone-derived (3α,5α)-3-hydroxy-pregnan-20-one (allopregnanolone; ALLO), modulate the expression of δ-GABAARs and the tonic conductance they mediate. Pregnancy produces large increases in ALLO and brain-region-specific homeostatic changes in δ-GABAARs expression. Here we show that in CA3, where most PV+ interneurons (INs) express δ-GABAARs, expression of δ-GABAARs on INs diminishes during pregnancy, but reverts to control levels within 48 h postpartum. These anatomical findings were corroborated by a pregnancy-related increase in the frequency of kainate-induced CA3 γ oscillations in vitro that could be countered by the NMDA-R antagonists D-AP5 and PPDA. Mimicking the typical hormonal conditions during pregnancy by supplementing 100 nM ALLO lowered the γ frequencies to levels found in virgin or postpartum mice. Our findings show that states of altered NS levels (e.g., pregnancy) may provoke perturbations in γ oscillatory activity through direct effects on the GABAergic system, and underscore the importance of δ-GABAARs homeostatic plasticity in maintaining constant network output despite large hormonal changes. Inaccurate coupling of NS levels to δ-GABAAR expression may facilitate abnormal neurological and psychiatric conditions such as epilepsy, post-partum depression, and post-partum psychosis, thus providing insights into potential new treatments.
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Affiliation(s)
- Isabella Ferando
- Department of Neurology, The David Geffen School of Medicine, University of California Los Angeles, CA 90095-733522, USA
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Saha S, Hu Y, Martin SC, Bandyopadhyay S, Russek SJ, Farb DH. Polycomblike protein PHF1b: a transcriptional sensor for GABA receptor activity. BMC Pharmacol Toxicol 2013; 14:37. [PMID: 23879974 PMCID: PMC3734045 DOI: 10.1186/2050-6511-14-37] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 06/17/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The γ-aminobutyric acid (GABA) type A receptor (GABA(A)R) contains the recognition sites for a variety of agents used in the treatment of brain disorders, including anxiety and epilepsy. A better understanding of how receptor expression is regulated in individual neurons may provide novel opportunities for therapeutic intervention. Towards this goal we have studied transcription of a GABA(A)R subunit gene (GABRB1) whose activity is autologously regulated by GABA via a 10 base pair initiator-like element (β(1)-INR). METHODS By screening a human cDNA brain library with a yeast one-hybrid assay, the Polycomblike (PCL) gene product PHD finger protein transcript b (PHF1b) was identified as a β(1)-INR associated protein. Promoter/reporter assays in primary rat cortical cells demonstrate that PHF1b is an activator at GABRB1, and chromatin immunoprecipitation assays reveal that presence of PHF1 at endogenous Gabrb1 is regulated by GABA(A)R activation. RESULTS PCL is a member of the Polycomb group required for correct spatial expression of homeotic genes in Drosophila. We now show that PHF1b recognition of β(1)-INR is dependent on a plant homeodomain, an adjacent helix-loop-helix, and short glycine rich motif. In neurons, it co-immunoprecipitates with SUZ12, a key component of the Polycomb Repressive Complex 2 (PRC2) that regulates a number of important cellular processes, including gene silencing via histone H3 lysine 27 trimethylation (H3K27me3). CONCLUSIONS The observation that chronic exposure to GABA reduces PHF1 binding and H3K27 monomethylation, which is associated with transcriptional activation, strongly suggests that PHF1b may be a molecular transducer of GABA(A)R function and thus GABA-mediated neurotransmission in the central nervous system.
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Affiliation(s)
- Shamol Saha
- Department of Pharmacology & Experimental Therapeutics, Laboratory of Translational Epilepsy, Boston University School of Medicine, Boston, MA 02118, USA
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Grabenstatter HL, Russek SJ, Brooks-Kayal AR. Molecular pathways controlling inhibitory receptor expression. Epilepsia 2013; 53 Suppl 9:71-8. [PMID: 23216580 DOI: 10.1111/epi.12036] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Epilepsy is a disease of complex etiology, and multiple molecular mechanisms contribute to its development. Temporal lobe epilepsy (TLE) may result from an initial precipitating event such as hypoxia, head injury, or prolonged seizure (i.e., status epilepticus [SE]), that is followed by a latent period of months to years before spontaneous seizures occur. γ-Aminobutyric acid (GABA)(A) receptor (GABA(A) R) subunit changes occur during this latent period and may persist following the onset of spontaneous seizures. Research into the molecular mechanisms regulating these changes and potential targets for intervention to reverse GABA(A) R subunit alterations have uncovered seizure-induced pathways that contribute to epileptogenesis. Several growth or transcription factors are known to be activated by SE, including (but not limited to): brain-derived neurotrophic factor (BDNF), cAMP response element binding protein (CREB), inducible cAMP early repressor (ICER), and early growth response factors (Egrs). Results of multiple studies suggest that these factors transcriptionally regulate GABA(A) R subunit gene expression in a way that is pertinent to the development of epilepsy. This article focuses on these signaling elements and describes their possible roles in gene regulatory pathways that may be critical in the development of chronic epilepsy.
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Affiliation(s)
- Heidi L Grabenstatter
- Translational Epilepsy Program, University of Colorado School of Medicine, Aurora, Colorado 80045, USA
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Beaumont TL, Yao B, Shah A, Kapatos G, Loeb JA. Layer-specific CREB target gene induction in human neocortical epilepsy. J Neurosci 2012; 32:14389-401. [PMID: 23055509 PMCID: PMC3478758 DOI: 10.1523/jneurosci.3408-12.2012] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Revised: 07/17/2012] [Accepted: 08/20/2012] [Indexed: 11/21/2022] Open
Abstract
Epilepsy is a disorder of recurrent seizures that affects 1% of the population. To understand why some areas of cerebral cortex produce seizures and others do not, we identified differentially expressed genes in human epileptic neocortex compared with nearby regions that did not produce seizures. The transcriptome that emerged strongly implicates MAPK signaling and CREB-dependent transcription, with 74% of differentially expressed genes containing a cAMP response element (CRE) in their proximal promoter, more than half of which are conserved. Despite the absence of recent seizures in these patients, epileptic brain regions prone to seizures showed persistent activation of ERK and CREB. Persistent CREB activation was directly linked to CREB-dependent gene transcription by chromatin immunoprecipitation that showed phosphorylated CREB constitutively associated with the proximal promoters of many of the induced target genes involved in neuronal signaling, excitability, and synaptic plasticity. A distinct spatial pattern of ERK activation was seen in superficial axodendritic processes of epileptic neocortex that colocalized with both CREB phosphorylation and CREB target gene induction in well demarcated populations of layer 2/3 neurons. These same neuronal lamina showed a marked increase in synaptic density. The findings generated in this study generate a robust and spatially restricted pattern of epileptic biomarkers and associated synaptic changes that could lead to new mechanistic insights and potential therapeutic targets for human epilepsy.
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Affiliation(s)
- Thomas L. Beaumont
- The Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan 48201
| | | | | | - Gregory Kapatos
- The Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Jeffrey A. Loeb
- Department of Neurology and
- The Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan 48201
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Verrotti A, D'Egidio C, Agostinelli S, Verrotti C, Pavone P. Diagnosis and management of catamenial seizures: a review. Int J Womens Health 2012; 4:535-41. [PMID: 23071424 PMCID: PMC3469236 DOI: 10.2147/ijwh.s28872] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Catamenial epilepsy is defined as a pattern of seizures that changes in severity during particular phases of the menstrual cycle, wherein estrogens are proconvulsant, increasing the neuronal excitability; and progesterone is anticonvulsant, enhancing GABA-mediated inhibition. Thus, changes in serum estradiol/progesterone ratio throughout a normal reproductive cycle bring about an increased or decreased risk of seizure occurrence. To date, there are no specific drug treatments for catamenial epilepsy however, non-hormonal and hormonal therapies have been proposed. The aim of this review is to report preclinical and clinical evidences about the relationship between female reproductive steroids and epileptic seizures, and to describe treatment approaches for catamenial epilepsy.
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Raible DJ, Frey LC, Cruz Del Angel Y, Russek SJ, Brooks-Kayal AR. GABA(A) receptor regulation after experimental traumatic brain injury. J Neurotrauma 2012; 29:2548-54. [PMID: 22827467 DOI: 10.1089/neu.2012.2483] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The gamma-aminobutyric acid (GABA) type A receptor (GABA(A)R) is responsible for most fast synaptic inhibition in the adult brain. The GABA(A)R protein is composed of multiple subunits that determine the distribution, properties, and dynamics of the receptor. Several studies have shown that the Janus kinase/signal transducer and activator of transcription (JaK/STAT) and early growth response 3 (Egr3) signaling pathways can alter GABA(A)R subunit expression after status epilepticus (SE). In this study we investigated changes in these pathways after experimental TBI in the rat using a lateral fluid percussion injury (FPI) model. Our results demonstrated changes in the expression of several GABA(A)R subunit levels after injury, including GABA(A)R α1 and α4 subunits. This change appears to be transcriptional, and there is an associated increase in the phosphorylation of STAT3, and an increase in the expression of Egr3 and inducible cAMP element repressor (ICER) after FPI. These findings suggest that the activation of the JaK/STAT and Egr3 pathways after TBI may regulate injury-related changes in GABA(A)R subunit expression.
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Affiliation(s)
- Daniel J Raible
- Neuroscience Program, University of Colorado, Anschutz Medical Campus, Aurora, Colorado, USA
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