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Mesarosova L, Scheper M, Iyer A, Anink JJ, Mills JD, Aronica E. miR-193b-3p/ PGC-1α pathway regulates an insulin dependent anti-inflammatory response in Parkinson's disease. Neurobiol Dis 2024; 199:106587. [PMID: 38950713 DOI: 10.1016/j.nbd.2024.106587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 06/18/2024] [Accepted: 06/28/2024] [Indexed: 07/03/2024] Open
Abstract
It has been shown that many miRNAs, including miR-193b-3p, are differentially expressed in Parkinson's disease (PD). Dysregulation of miR-193b-3p/PGC-1α axis may alter homeostasis in cells and can induce an inflammatory response commonly accompanied by metabolic disturbances. The aim of the present study is to investigate if dysregulation of the miR-193-3p/PGC-1α axis may contribute to the pathological changes observed in the PD brain. Brain tissue were obtained from middle frontal gyrus of non-demented controls and individuals with a PD diagnosis. RT-qPCR was used to determine the expression of miR-193b-3p and in situ hybridization (ISH) and immunological analysis were employed to establish the cellular distribution of miR-193b-3p. Functional assays were performed using SH-SY5Y cells, including transfection and knock-down of miR-193b-3p. We found significantly lower expression of miR-193b-3p in the early stages of PD (PD4) which increased throughout disease progression. Furthermore, altered expression of PGC-1α suggested a direct inhibitory effect of miR-193b-3p in the brain of individuals with PD. Moreover, we observed changes in expression of insulin after transfection of SH-SY5Y cells with miR-193b-3p, which led to dysregulation in the expression of several pro- or anti - inflammatory genes. Our findings indicate that the miR-193b-3p/PGC-1α axis is involved in the regulation of insulin signaling. This regulation is crucial, since insulin induced inflammatory response may serve as a protective mechanism during acute situations but potentially evolve into a pathological process in chronic conditions. This novel regulatory mechanism may represent an interesting therapeutic target with potential benefits for various neurodegenerative diseases.
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Affiliation(s)
- Lucia Mesarosova
- Amsterdam UMC location University of Amsterdam, Department of (Neuro)Pathology Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, the Netherlands.
| | - Mirte Scheper
- Amsterdam UMC location University of Amsterdam, Department of (Neuro)Pathology Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, the Netherlands
| | - Anand Iyer
- Amsterdam UMC location University of Amsterdam, Department of (Neuro)Pathology Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, the Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, the Netherlands
| | - Jasper J Anink
- Amsterdam UMC location University of Amsterdam, Department of (Neuro)Pathology Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, the Netherlands
| | - James D Mills
- Amsterdam UMC location University of Amsterdam, Department of (Neuro)Pathology Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, the Netherlands.
| | - Eleonora Aronica
- Amsterdam UMC location University of Amsterdam, Department of (Neuro)Pathology Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, the Netherlands
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2
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Ferrer I. Historical review: The golden age of the Golgi method in human neuropathology. J Neuropathol Exp Neurol 2024; 83:375-395. [PMID: 38622902 DOI: 10.1093/jnen/nlae031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024] Open
Abstract
Golgi methods were used to study human neuropathology in the 1970s, 1980s, and 1990s of the last century. Although a relatively small number of laboratories applied these methods, their impact was crucial by increasing knowledge about: (1) the morphology, orientation, and localization of neurons in human cerebral and cerebellar malformations and ganglionic tumors, and (2) the presence of abnormal structures including large and thin spines (spine dysgenesis) in several disorders linked to mental retardation, focal enlargements of the axon hillock and dendrites (meganeurites) in neuronal storage diseases, growth cone-like appendages in Alzheimer disease, as well as abnormal structures in other dementias. Although there were initial concerns about their reliability, reduced dendritic branches and dendritic spines were identified as common alterations in mental retardation, dementia, and other pathological conditions. Similar observations in appropriate experimental models have supported many abnormalities that were first identified using Golgi methods in human material. Moreover, electron microscopy, immunohistochemistry, fluorescent tracers, and combined methods have proven the accuracy of pioneering observations uniquely visualized as 3D images of fully stained individual neurons. Although Golgi methods had their golden age many years ago, these methods may still be useful complementary tools in human neuropathology.
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Affiliation(s)
- Isidro Ferrer
- Department of Pathology and Experimental Therapeutics, University of Barcelona, Hospitalet de LLobregat, Spain
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3
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D'Antoni S, Schiavi S, Buzzelli V, Giuffrida S, Feo A, Ascone F, Busceti CL, Nicoletti F, Trezza V, Catania MV. Group I and group II metabotropic glutamate receptors are upregulated in the synapses of infant rats prenatally exposed to valproic acid. Psychopharmacology (Berl) 2023; 240:2617-2629. [PMID: 37707611 PMCID: PMC10640443 DOI: 10.1007/s00213-023-06457-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 08/23/2023] [Indexed: 09/15/2023]
Abstract
RATIONALE Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social interaction and restricted/stereotyped behavior. Prenatal exposure to valproic acid (VPA) is associated with an increased risk of developing ASD in humans and autistic-like behaviors in rodents. Increasing evidence indicates that dysfunctions of glutamate receptors at synapses are associated with ASD. In the VPA rat model, an involvement of glutamate receptors in autism-like phenotypes has been suggested; however, few studies were carried out on metabotropic glutamate (mGlu) receptors. OBJECTIVES We examined the protein expression levels of group I (mGlu1 and mGlu5) and group II (mGlu2/3) mGlu receptors in rats prenatally exposed to VPA and evaluated the effect of mGlu receptor modulation on an early autism-like phenotype in these animals. METHODS We used western blotting analysis on synaptosomes obtained from forebrain of control and VPA rats at different ages (postnatal day P13, 35, 90) and carried out ultrasonic vocalization (USV) emission test in infant control and VPA rats. RESULTS The expression levels of all these receptors were significantly increased in infant VPA rats. No changes were detected in adolescent and adult rats. An acute treatment with the preferential mGlu2/3 antagonist, LY341495, attenuated the impairment in the USV emission in VPA rats. No effect was observed after a treatment with the mGlu5 selective antagonist, MTEP. CONCLUSIONS Our findings demonstrate that the expression of group I and group II mGlu receptors is upregulated at synapses of infant VPA rats and suggest that mGlu2/3 receptor modulation may have a therapeutic potential in ASD.
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Affiliation(s)
- Simona D'Antoni
- Institute for Biomedical Research and Innovation, National Research Council (IRIB-CNR), Catania, Italy
| | - Sara Schiavi
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Rome, Italy
| | - Valeria Buzzelli
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Rome, Italy
| | - Samuele Giuffrida
- Institute for Biomedical Research and Innovation, National Research Council (IRIB-CNR), Catania, Italy
| | - Alessandro Feo
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Rome, Italy
| | - Fabrizio Ascone
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Rome, Italy
| | | | - Ferdinando Nicoletti
- IRCCS Neuromed, Pozzilli, Italy
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Viviana Trezza
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Rome, Italy
- Neuroendocrinology, Metabolism and Neuropharmacology Unit, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Maria Vincenza Catania
- Institute for Biomedical Research and Innovation, National Research Council (IRIB-CNR), Catania, Italy.
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4
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Zimmer TS, Broekaart DWM, Gruber VE, van Vliet EA, Mühlebner A, Aronica E. Tuberous Sclerosis Complex as Disease Model for Investigating mTOR-Related Gliopathy During Epileptogenesis. Front Neurol 2020; 11:1028. [PMID: 33041976 PMCID: PMC7527496 DOI: 10.3389/fneur.2020.01028] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 08/06/2020] [Indexed: 12/13/2022] Open
Abstract
Tuberous sclerosis complex (TSC) represents the prototypic monogenic disorder of the mammalian target of rapamycin (mTOR) pathway dysregulation. It provides the rational mechanistic basis of a direct link between gene mutation and brain pathology (structural and functional abnormalities) associated with a complex clinical phenotype including epilepsy, autism, and intellectual disability. So far, research conducted in TSC has been largely neuron-oriented. However, the neuropathological hallmarks of TSC and other malformations of cortical development also include major morphological and functional changes in glial cells involving astrocytes, oligodendrocytes, NG2 glia, and microglia. These cells and their interglial crosstalk may offer new insights into the common neurobiological mechanisms underlying epilepsy and the complex cognitive and behavioral comorbidities that are characteristic of the spectrum of mTOR-associated neurodevelopmental disorders. This review will focus on the role of glial dysfunction, the interaction between glia related to mTOR hyperactivity, and its contribution to epileptogenesis in TSC. Moreover, we will discuss how understanding glial abnormalities in TSC might give valuable insight into the pathophysiological mechanisms that could help to develop novel therapeutic approaches for TSC or other pathologies characterized by glial dysfunction and acquired mTOR hyperactivation.
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Affiliation(s)
- Till S Zimmer
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Diede W M Broekaart
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | | | - Erwin A van Vliet
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, Netherlands
| | - Angelika Mühlebner
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands
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5
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van Vliet EA, Iyer AM, Mesarosova L, Çolakoglu H, Anink JJ, van Tellingen O, Maragakis NJ, Shefner J, Bunt T, Aronica E. Expression and Cellular Distribution of P-Glycoprotein and Breast Cancer Resistance Protein in Amyotrophic Lateral Sclerosis Patients. J Neuropathol Exp Neurol 2020; 79:266-276. [PMID: 31999342 PMCID: PMC7036662 DOI: 10.1093/jnen/nlz142] [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: 06/15/2019] [Revised: 11/23/2019] [Accepted: 12/20/2019] [Indexed: 12/11/2022] Open
Abstract
For amyotrophic lateral sclerosis (ALS), achieving and maintaining effective drug levels in the brain is challenging due to the activity of ATP-binding cassette (ABC) transporters which efflux drugs that affect drug exposure and response in the brain. We investigated the expression and cellular distribution of the ABC transporters P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) using immunohistochemistry in spinal cord (SC), motor cortex, and cerebellum from a large cohort of genetically well characterized ALS patients (n = 25) and controls (n = 14). The ALS group included 17 sporadic (sALS) and 8 familial (fALS) patients. Strong P-gp expression was observed in endothelial cells in both control and ALS specimens. Immunohistochemical analysis showed higher P-gp expression in reactive astroglial cells in both gray (ventral horn) and white matter of the SC, as well as in the motor cortex of all ALS patients, as compared with controls. BCRP expression was higher in glia in the SC and in blood vessels and glia in the motor cortex of ALS patients, as compared with controls. P-gp and BCRP immunoreactivity did not differ between sALS and fALS cases. The upregulation of both ABC transporters in the brain may explain multidrug resistance in ALS patients and has implications for the use of both approved and experimental therapeutics.
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Affiliation(s)
- Erwin A van Vliet
- From the Amsterdam UMC, University of Amsterdam, Department of (Neuro)Pathology, Amsterdam Neuroscience.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam
| | - Anand M Iyer
- From the Amsterdam UMC, University of Amsterdam, Department of (Neuro)Pathology, Amsterdam Neuroscience
| | - Lucia Mesarosova
- From the Amsterdam UMC, University of Amsterdam, Department of (Neuro)Pathology, Amsterdam Neuroscience
| | - Hilal Çolakoglu
- Division of Pharmacology, The Netherlands Cancer Institute (HÇ, OvT), Amsterdam, The Netherlands
| | - Jasper J Anink
- From the Amsterdam UMC, University of Amsterdam, Department of (Neuro)Pathology, Amsterdam Neuroscience
| | - Olaf van Tellingen
- Division of Pharmacology, The Netherlands Cancer Institute (HÇ, OvT), Amsterdam, The Netherlands
| | - Nicholas J Maragakis
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jeremy Shefner
- Department of Neurology, Barrow Neurological Institute, Phoenix, Arizona
| | - Ton Bunt
- Izumi Biosciences, Inc., Lexington, Massachusetts
| | - Eleonora Aronica
- From the Amsterdam UMC, University of Amsterdam, Department of (Neuro)Pathology, Amsterdam Neuroscience
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6
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Zhang Z, Li N, Wei X, Chen B, Zhang Y, Zhao Y, Hu X, Hou S. GRM4 inhibits the proliferation, migration, and invasion of human osteosarcoma cells through interaction with CBX4. Biosci Biotechnol Biochem 2020; 84:279-289. [PMID: 31581881 DOI: 10.1080/09168451.2019.1673147] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
ABSTRACT
In recent years, the survey of metabolic glutamate receptor 4 (GRM4) in tumor biology has been gradually concerned. There are currently few studies on GRM4 in osteosarcoma, and the biological function is not clear. Analysis of TCGA database showed that there was no substantial deviation in the expression of GRM4 between osteosarcoma and normal tissues. In the subsequent experiments, there is no significant difference in either mRNA or protein levels among immortalized human osteoblasts and various osteosarcoma cells. With the overexpression of GRM4, cell proliferation, migration and invasion were inhibited obviously. It was further revealed that GRM4 can interact with CBX4 to restrict the nuclear localization of CBX4 and affect the transcriptional activity of HIF-1α. This is the evidence supporting the interaction between GRM4 and CBX4, which could inhibit the malignant behavior of osteosarcoma cells through the GRM4/CBX4/HIF-1α signaling pathway.
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Affiliation(s)
- Zengliang Zhang
- Department of orthopaedics, Fourth Medical Center of PLA General Hospital, Beijing, China
- Chinese PLA Medical School, Beijing, China
| | - Nan Li
- Department of orthopaedics, Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Xing Wei
- Aerospace Center Hospital, Beijing, China
| | - Bingyao Chen
- Department of orthopaedics, Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Yinglong Zhang
- Department of orthopaedics, Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Yantao Zhao
- Department of orthopaedics, Fourth Medical Center of PLA General Hospital, Beijing, China
- Beijing Engineering Research Center of Orthopaedic Implants, Beijing, China
| | - Xiantong Hu
- Department of orthopaedics, Fourth Medical Center of PLA General Hospital, Beijing, China
- Beijing Engineering Research Center of Orthopaedic Implants, Beijing, China
| | - Shuxun Hou
- Department of orthopaedics, Fourth Medical Center of PLA General Hospital, Beijing, China
- Orthopedic Institute of PLA, Beijing, China
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7
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Short B, Kozek L, Harmsen H, Zhang B, Wong M, Ess KC, Fu C, Naftel R, Pearson MM, Carson RP. Cerebral aquaporin-4 expression is independent of seizures in tuberous sclerosis complex. Neurobiol Dis 2019; 129:93-101. [PMID: 31078684 DOI: 10.1016/j.nbd.2019.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/23/2019] [Accepted: 05/08/2019] [Indexed: 12/26/2022] Open
Abstract
Astrocytes serve many functions in the human brain, many of which focus on maintenance of homeostasis. Astrocyte dysfunction in Tuberous Sclerosis Complex (TSC) has long been appreciated with activation of the mTORC1 signaling pathway resulting in gliosis and possibly contributing to the very frequent phenotype of epilepsy. We hypothesized that aberrant expression of the astrocyte protein aquaporin-4 (AQP4) may be present in TSC and contribute to disease pathology. Characterization of AQP4 expression in epileptic cortex from TSC patients demonstrated a diffuse increase in AQP4. To determine if this was due to exposure to seizures, we examined Aqp4 expression in mouse models of TSC in which Tsc1 or Tsc2 inactivation was targeted to astrocytes or glial progenitors, respectively. Loss of either Tsc1 or Tsc2 from astrocytes resulted in a marked increase in Aqp4 expression which was sensitive to mTORC1 inhibition with rapamycin. Our findings in both TSC epileptogenic cortex and in a variety of astrocyte culture models demonstrate for the first time that AQP4 expression is dysregulated in TSC. The extent to which AQP4 contributes to epilepsy in TSC is not known, though the similarities in AQP4 expression between TSC and temporal lobe epilepsy supports further studies targeting AQP4 in TSC.
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Affiliation(s)
- Brittany Short
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, United States
| | - Lindsay Kozek
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, United States; Vanderbilt Brain Institute, Vanderbilt University, United States
| | - Hannah Harmsen
- Department of Pathology, Vanderbilt University Medical Center, United States
| | - Bo Zhang
- Departments of Neurology, Pediatrics, and Neuroscience, Washington University School of Medicine, United States
| | - Michael Wong
- Departments of Neurology, Pediatrics, and Neuroscience, Washington University School of Medicine, United States
| | - Kevin C Ess
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, United States; Vanderbilt Brain Institute, Vanderbilt University, United States
| | - Cary Fu
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, United States
| | - Robert Naftel
- Department of Neurosurgery, Vanderbilt University Medical Center, United States
| | | | - Robert P Carson
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, United States; Vanderbilt Brain Institute, Vanderbilt University, United States; Department of Pharmacology, Vanderbilt University Medical Center, United States.
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8
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Okamoto SI, Prikhodko O, Pina-Crespo J, Adame A, McKercher SR, Brill LM, Nakanishi N, Oh CK, Nakamura T, Masliah E, Lipton SA. NitroSynapsin for the treatment of neurological manifestations of tuberous sclerosis complex in a rodent model. Neurobiol Dis 2019; 127:390-397. [PMID: 30928642 DOI: 10.1016/j.nbd.2019.03.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 03/07/2019] [Accepted: 03/26/2019] [Indexed: 12/13/2022] Open
Abstract
Tuberous sclerosis (TSC) is an autosomal dominant disorder caused by heterozygous mutations in the TSC1 or TSC2 gene. TSC is often associated with neurological, cognitive, and behavioral deficits. TSC patients also express co-morbidity with anxiety and mood disorders. The mechanism of pathogenesis in TSC is not entirely clear, but TSC-related neurological symptoms are accompanied by excessive glutamatergic activity and altered synaptic spine structures. To address whether extrasynaptic (e)NMDA-type glutamate receptor (NMDAR) antagonists, as opposed to antagonists that block physiological phasic synaptic activity, can ameliorate the synaptic and behavioral features of this disease, we utilized the Tsc2+/- mouse model of TSC to measure biochemical, electrophysiological, histological, and behavioral parameters in the mice. We found that antagonists that preferentially block tonic activity as found at eNMDARs, particularly the newer drug NitroSynapsin, provide biological and statistically significant improvement in Tsc2+/- phenotypes. Accompanying this improvement was correction of activity in the p38 MAPK-TSC-Rheb-mTORC1-S6K1 pathway. Deficits in hippocampal long-term potentiation (LTP), histological loss of synapses, and behavioral fear conditioning in Tsc2+/- mice were all improved after treatment with NitroSynapsin. Taken together, these results suggest that amelioration of excessive excitation, by limiting aberrant eNMDAR activity, may represent a novel treatment approach for TSC.
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Affiliation(s)
| | - Olga Prikhodko
- Biomedical Sciences Graduate Program, University of California San Diego, School of Medicine, La Jolla, CA 92093, USA
| | - Juan Pina-Crespo
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Anthony Adame
- Department of Neurosciences, University of California San Diego, School of Medicine, La Jolla, CA 92093, USA
| | - Scott R McKercher
- Scintillon Institute, San Diego, CA 92121, USA; Neuroscience Translational Center, Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Laurence M Brill
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | | | - Chang-Ki Oh
- Scintillon Institute, San Diego, CA 92121, USA; Neuroscience Translational Center, Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Tomohiro Nakamura
- Scintillon Institute, San Diego, CA 92121, USA; Neuroscience Translational Center, Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Eliezer Masliah
- Department of Neurosciences, University of California San Diego, School of Medicine, La Jolla, CA 92093, USA
| | - Stuart A Lipton
- Scintillon Institute, San Diego, CA 92121, USA; Department of Neurosciences, University of California San Diego, School of Medicine, La Jolla, CA 92093, USA; Neuroscience Translational Center, Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA.
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9
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Mühlebner A, Bongaarts A, Sarnat HB, Scholl T, Aronica E. New insights into a spectrum of developmental malformations related to mTOR dysregulations: challenges and perspectives. J Anat 2019; 235:521-542. [PMID: 30901081 DOI: 10.1111/joa.12956] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2019] [Indexed: 12/20/2022] Open
Abstract
In recent years the role of the mammalian target of rapamycin (mTOR) pathway has emerged as crucial for normal cortical development. Therefore, it is not surprising that aberrant activation of mTOR is associated with developmental malformations and epileptogenesis. A broad spectrum of malformations of cortical development, such as focal cortical dysplasia (FCD) and tuberous sclerosis complex (TSC), have been linked to either germline or somatic mutations in mTOR pathway-related genes, commonly summarised under the umbrella term 'mTORopathies'. However, there are still a number of unanswered questions regarding the involvement of mTOR in the pathophysiology of these abnormalities. Therefore, a monogenetic disease, such as TSC, can be more easily applied as a model to study the mechanisms of epileptogenesis and identify potential new targets of therapy. Developmental neuropathology and genetics demonstrate that FCD IIb and hemimegalencephaly are the same diseases. Constitutive activation of mTOR signalling represents a shared pathogenic mechanism in a group of developmental malformations that have histopathological and clinical features in common, such as epilepsy, autism and other comorbidities. We seek to understand the effect of mTOR dysregulation in a developing cortex with the propensity to generate seizures as well as the aftermath of the surrounding environment, including the white matter.
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Affiliation(s)
- A Mühlebner
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - A Bongaarts
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - H B Sarnat
- Departments of Paediatrics, Pathology (Neuropathology) and Clinical Neurosciences, University of Calgary Cumming School of Medicine and Alberta Children's Hospital Research Institute (Owerko Centre), Calgary, AB, Canada
| | - T Scholl
- Department of Paediatric and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - E Aronica
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Amsterdam, The Netherlands
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10
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Conditional Knock-out of mGluR5 from Astrocytes during Epilepsy Development Impairs High-Frequency Glutamate Uptake. J Neurosci 2018; 39:727-742. [PMID: 30504280 DOI: 10.1523/jneurosci.1148-18.2018] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 11/11/2018] [Accepted: 11/18/2018] [Indexed: 11/21/2022] Open
Abstract
Astrocyte expression of metabotropic glutamate receptor 5 (mGluR5) is consistently observed in resected tissue from patients with epilepsy and is equally prevalent in animal models of epilepsy. However, little is known about the functional signaling properties or downstream consequences of astrocyte mGluR5 activation during epilepsy development. In the rodent brain, astrocyte mGluR5 expression is developmentally regulated and confined in expression/function to the first weeks of life, with similar observations made in human control tissue. Herein, we demonstrate that mGluR5 expression and function dramatically increase in a mouse model of temporal lobe epilepsy. Interestingly, in both male and female mice, mGluR5 function persists in the astrocyte throughout the process of epileptogenesis following status epilepticus. However, mGluR5 expression and function are transient in animals that do not develop epilepsy over an equivalent time period, suggesting that patterns of mGluR5 expression may signify continuing epilepsy development or its resolution. We demonstrate that, during epileptogenesis, astrocytes reacquire mGluR5-dependent calcium transients following agonist application or synaptic glutamate release, a feature of astrocyte-neuron communication absent since early development. Finally, we find that the selective and conditional knock-out of mGluR5 signaling from astrocytes during epilepsy development slows the rate of glutamate clearance through astrocyte glutamate transporters under high-frequency stimulation conditions, a feature that suggests astrocyte mGluR5 expression during epileptogenesis may recapitulate earlier developmental roles in regulating glutamate transporter function.SIGNIFICANCE STATEMENT In development, astrocyte mGluR5 signaling plays a critical role in regulating structural and functional interactions between astrocytes and neurons at the tripartite synapse. Notably, mGluR5 signaling is a positive regulator of astrocyte glutamate transporter expression and function, an essential component of excitatory signaling regulation in hippocampus. After early development, astrocyte mGluR5 expression is downregulated, but reemerges in animal models of temporal lobe epilepsy (TLE) development and patient epilepsy samples. We explored the hypothesis that astrocyte mGluR5 reemergence recapitulates earlier developmental roles during TLE acquisition. Our work demonstrates that astrocytes with mGluR5 signaling during TLE development perform faster glutamate uptake in hippocampus, revealing a previously unexplored role for astrocyte mGluR5 signaling in hypersynchronous pathology.
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11
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Huang CY, Hsueh YM, Chen LC, Cheng WC, Yu CC, Chen WJ, Lu TL, Lan KJ, Lee CH, Huang SP, Bao BY. Clinical significance of glutamate metabotropic receptors in renal cell carcinoma risk and survival. Cancer Med 2018; 7:6104-6111. [PMID: 30488581 PMCID: PMC6308098 DOI: 10.1002/cam4.1901] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 11/07/2018] [Accepted: 11/09/2018] [Indexed: 01/14/2023] Open
Abstract
Accumulating evidence suggests the roles of glutamate metabotropic receptors (GRMs) in cancer, in addition to synaptic signalling. The present study assessed the associations of genetic variants in eight GRM genes with regard to risk and overall survival (OS) in 780 renal cell carcinoma (RCC) patients and controls. After adjustment for known risk factors, GRM5 rs7102764 T was associated with an increased risk of RCC (P = 0.006). Additional analysis has provided evidence that rs7102764 T was correlated with a higher expression of GRM5, which is consistently found to be upregulated in tumours, compared to normal tissues. Furthermore, the GRM3 rs701332 C, GRM4 rs2499707 T, and GRM4 rs4713742 T alleles were significantly associated with a poorer OS (P ≤ 0.030). The three loci were also observed to have strong cumulative effects on OS. Additional analysis has revealed a significant genotype‐expression correlation of rs2499707 T with increased GRM4 expression, which in turn leads to poorer OS in patients with RCC. GRMs might be involved in RCC development and progression, and genetic variants in GRMs might be promising biomarkers.
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Affiliation(s)
- Chao-Yuan Huang
- Department of Urology, College of Medicine, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan.,Department of Urology, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu, Taiwan
| | - Yu-Mei Hsueh
- Department of Family Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.,Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Lih-Chyang Chen
- Department of Medicine, Mackay Medical College, New Taipei City, Taiwan
| | - Wei-Chung Cheng
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan.,Research Center for Tumor Medical Science, China Medical University, Taichung, Taiwan.,Drug Development Center, China Medical University, Taichung, Taiwa
| | - Chia-Cheng Yu
- Division of Urology, Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.,Department of Urology, School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Department of Pharmacy, Tajen University, Pingtung, Taiwan
| | - Wei-Jen Chen
- School of Public Health, College of Public Health, Taipei Medical University, Taipei, Taiwan
| | - Te-Ling Lu
- Department of Pharmacy, China Medical University, Taichung, Taiwan
| | - Kuo-Jin Lan
- Department of Pharmacy, China Medical University, Taichung, Taiwan
| | - Cheng-Hsueh Lee
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Shu-Pin Huang
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.,Department of Urology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.,Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.,Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Bo-Ying Bao
- Department of Pharmacy, China Medical University, Taichung, Taiwan.,Sex Hormone Research Center, China Medical University Hospital, Taichung, Taiwan.,Department of Nursing, Asia University, Taichung, Taiwan
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12
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Nardecchia F, Orlando R, Iacovelli L, Colamartino M, Fiori E, Leuzzi V, Piccinin S, Nistico R, Puglisi-Allegra S, Di Menna L, Battaglia G, Nicoletti F, Pascucci T. Targeting mGlu5 Metabotropic Glutamate Receptors in the Treatment of Cognitive Dysfunction in a Mouse Model of Phenylketonuria. Front Neurosci 2018; 12:154. [PMID: 29615849 PMCID: PMC5864888 DOI: 10.3389/fnins.2018.00154] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 02/26/2018] [Indexed: 11/23/2022] Open
Abstract
We studied group-I metabotropic glutamate (mGlu) receptors in Pahenu2 (ENU2) mice, which mimic the genetics and neurobiology of human phenylketonuria (PKU), a metabolic disorder characterized, if untreated, by autism, and intellectual disability (ID). Male ENU2 mice showed increased mGlu5 receptor protein levels in the hippocampus and corpus striatum (but not in the prefrontal cortex) whereas the transcript of the mGlu5 receptor was unchanged. No changes in mGlu1 receptor mRNA and protein levels were found in any of the three brain regions of ENU2 mice. We extended the analysis to Homer proteins, which act as scaffolds by linking mGlu1 and mGlu5 receptors to effector proteins. Expression of the long isoforms of Homer was significantly reduced in the hippocampus of ENU2 mice, whereas levels of the short Homer isoform (Homer 1a) were unchanged. mGlu5 receptors were less associated to immunoprecipitated Homer in the hippocampus of ENU2 mice. The lack of mGlu5 receptor-mediated long-term depression (LTD) in wild-type mice (of BTBR strain) precluded the analysis of hippocampal synaptic plasticity in ENU2 mice. We therefore performed a behavioral analysis to examine whether pharmacological blockade of mGlu5 receptors could correct behavioral abnormalities in ENU2 mice. Using the same apparatus we sequentially assessed locomotor activity, object exploration, and spatial object recognition (spatial novelty test) after displacing some of the objects from their original position in the arena. Systemic treatment with the mGlu5 receptor antagonist, MPEP (20 mg/kg, i.p.), had a striking effect in the spatial novelty test by substantially increasing the time spent in exploring the displaced objects in ENU2 mice (but not in wild-type mice). These suggest a role for mGlu5 receptors in the pathophysiology of ID in PKU and suggest that, also in adult untreated animals, cognitive dysfunction may be improved by targeting these receptors with an appropriate therapy.
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Affiliation(s)
- Francesca Nardecchia
- Department of Physiology and Pharmacology, Sapienza Università di Roma, Rome, Italy.,Department of Pediatrics and Child Neuropsychiatry, Sapienza Università di Roma, Rome, Italy
| | - Rosamaria Orlando
- Department of Physiology and Pharmacology, Sapienza Università di Roma, Rome, Italy
| | - Luisa Iacovelli
- Department of Physiology and Pharmacology, Sapienza Università di Roma, Rome, Italy
| | - Marco Colamartino
- Daniel Bovet Department of Psychology, Neurobiology Research Center, Sapienza Università di Roma, Rome, Italy
| | - Elena Fiori
- Daniel Bovet Department of Psychology, Neurobiology Research Center, Sapienza Università di Roma, Rome, Italy
| | - Vincenzo Leuzzi
- Department of Pediatrics and Child Neuropsychiatry, Sapienza Università di Roma, Rome, Italy
| | - Sonia Piccinin
- Department of Physiology and Pharmacology, Sapienza Università di Roma, Rome, Italy.,Department of Biology, Università degli Studi di Roma Tor Vergata, Rome, Italy
| | - Robert Nistico
- Department of Biology, Università degli Studi di Roma Tor Vergata, Rome, Italy
| | - Stefano Puglisi-Allegra
- Daniel Bovet Department of Psychology, Neurobiology Research Center, Sapienza Università di Roma, Rome, Italy.,IRCCS Foundation Santa Lucia, Rome, Italy
| | | | | | - Ferdinando Nicoletti
- Department of Physiology and Pharmacology, Sapienza Università di Roma, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Tiziana Pascucci
- Daniel Bovet Department of Psychology, Neurobiology Research Center, Sapienza Università di Roma, Rome, Italy.,IRCCS Foundation Santa Lucia, Rome, Italy
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13
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Bai XX, Gu L, Yang HM, Xi SS, Xia N, Zhang S, Zhang H. Downregulation of metabotropic glutamate receptor 5 inhibits hepatoma development in a neurotoxin rotenone-induced Parkinson's disease model. Toxicol Lett 2018; 288:71-81. [PMID: 29458170 DOI: 10.1016/j.toxlet.2018.02.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 02/13/2018] [Accepted: 02/13/2018] [Indexed: 12/28/2022]
Abstract
Clinical epidemiological studies have shown that there is a link between Parkinson's disease (PD) and cancer, but how PD regulates cancer development remains unknown. In our study, the effect of metabotropic glutamate receptor 5 (mGlu5) on hepatoma was explored in a rotenone-induced PD model both in vitro and in vivo. We found that conditioned media derived from MN9D dopaminergic neuronal cells by rotenone-induced toxicity inhibited the growth, migration, invasion and promoted apoptosis of Hepa1-6 cells, which corresponded with decreased expression of mGlu5. Furthermore, treatment with 2-methyl-6-(phenylethynyl)pyridine (MPEP), a mGlu5 antagonist and knockdown of mGlu5, further reduced ATP levels and migration distance, and increased cleavage of caspase-3 in Hepa1-6 cells. Additionally, we found that conditioned media derived from rotenone-treated MN9D dopaminergic neuronal cells enhanced reactive oxygen species (ROS) generation and JNK phosphorylation, which could be further increased by MPEP treatment, and attenuated by mGlu5 agonist, (RS)-2-Chloro-5-hydroxyphenylglycine (CHPG) and ROS scavenger, N-acetyl-l-cysteine (NAC). The results indicated that down-regulation of mGlu5 promoted cell apoptosis through the intracellular ROS/JNK signaling pathway in a rotenone-induced cellular PD model. These findings were confirmed in vivo in a rotenone-induced rat model of PD combined with diethylnitrosamine (DEN)-induced hepatoma. Expression of Ki67 was decreased, and the levels of caspase-3 and p-JNK were increased in this model, which was accompanied by a decrease in protein expression of mGlu5. The study suggest that negative regulation of mGlu5 may inhibit hepatoma development in a rotenone-induced PD model, and as such may help with our further understanding of the correlation between PD and cancer.
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Affiliation(s)
- Xiao Xu Bai
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorder, Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Li Gu
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorder, Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Hui Min Yang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorder, Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Shao Song Xi
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorder, Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Ning Xia
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorder, Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Song Zhang
- Shanxi Academy of Analytical Science, 030006, China
| | - Hong Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorder, Ministry of Education, Capital Medical University, Beijing 100069, China.
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14
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Curatolo P, Moavero R, van Scheppingen J, Aronica E. mTOR dysregulation and tuberous sclerosis-related epilepsy. Expert Rev Neurother 2018; 18:185-201. [DOI: 10.1080/14737175.2018.1428562] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital, Rome, Italy
| | - Romina Moavero
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital, Rome, Italy
- Child Neurology Unit, Neuroscience and Neurorehabilitation Department, “Bambino Gesù” Children’s Hospital, IRCCS, Rome, Italy
| | - Jackelien van Scheppingen
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN), The Netherlands
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15
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Neuronal Glutamate Transporters Control Dopaminergic Signaling and Compulsive Behaviors. J Neurosci 2017; 38:937-961. [PMID: 29229708 DOI: 10.1523/jneurosci.1906-17.2017] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 11/24/2017] [Accepted: 12/01/2017] [Indexed: 12/21/2022] Open
Abstract
There is an ongoing debate on the contribution of the neuronal glutamate transporter EAAC1 to the onset of compulsive behaviors. Here, we used behavioral, electrophysiological, molecular, and viral approaches in male and female mice to identify the molecular and cellular mechanisms by which EAAC1 controls the execution of repeated motor behaviors. Our findings show that, in the striatum, a brain region implicated with movement execution, EAAC1 limits group I metabotropic glutamate receptor (mGluRI) activation, facilitates D1 dopamine receptor (D1R) expression, and ensures long-term synaptic plasticity. Blocking mGluRI in slices from mice lacking EAAC1 restores D1R expression and synaptic plasticity. Conversely, activation of intracellular signaling pathways coupled to mGluRI in D1R-containing striatal neurons of mice expressing EAAC1 leads to reduced D1R protein level and increased stereotyped movement execution. These findings identify new molecular mechanisms by which EAAC1 can shape glutamatergic and dopaminergic signals and control repeated movement execution.SIGNIFICANCE STATEMENT Genetic studies implicate Slc1a1, a gene encoding the neuronal glutamate transporter EAAC1, with obsessive-compulsive disorder (OCD). EAAC1 is abundantly expressed in the striatum, a brain region that is hyperactive in OCD. What remains unknown is how EAAC1 shapes synaptic function in the striatum. Our findings show that EAAC1 limits activation of metabotropic glutamate receptors (mGluRIs) in the striatum and, by doing so, promotes D1 dopamine receptor (D1R) expression. Targeted activation of signaling cascades coupled to mGluRIs in mice expressing EAAC1 reduces D1R expression and triggers repeated motor behaviors. These findings provide new information on the molecular basis of OCD and suggest new avenues for its treatment.
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16
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Bongaarts A, Giannikou K, Reinten RJ, Anink JJ, Mills JD, Jansen FE, Spliet GW, den Dunnen WF, Coras R, Blümcke I, Paulus W, Scholl T, Feucht M, Kotulska K, Jozwiak S, Buccoliero AM, Caporalini C, Giordano F, Genitori L, Söylemezoğlu F, Pimentel J, Nellist M, Schouten-van Meeteren AY, Nag A, Mühlebner A, Kwiatkowski DJ, Aronica E. Subependymal giant cell astrocytomas in Tuberous Sclerosis Complex have consistent TSC1/TSC2 biallelic inactivation, and no BRAF mutations. Oncotarget 2017; 8:95516-95529. [PMID: 29221145 PMCID: PMC5707039 DOI: 10.18632/oncotarget.20764] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 07/31/2017] [Indexed: 12/12/2022] Open
Abstract
Subependymal giant cell astrocytomas (SEGAs) are rare, low-grade glioneuronal brain tumors that occur almost exclusively in patients with tuberous sclerosis complex (TSC). Though histologically benign, SEGAs can lead to serious neurological complications, including hydrocephalus, intractable seizures and death. Previous studies in a limited number of SEGAs have provided evidence for a biallelic two-hit inactivation of either TSC1 or TSC2, resulting in constitutive activation of the mechanistic target of rapamycin complex 1 pathway. The activating BRAF V600E mutation is a common genetic alteration in low grade gliomas and glioneuronal tumors, and has been reported in SEGAs as well. In the present study, we assessed the prevalence of the BRAF V600E mutation in a large cohort of TSC related SEGAs (n=58 patients including 56 with clinical TSC) and found no evidence of either BRAF V600E or other mutations in BRAF. To confirm that these SEGAs fit the classic model of two hit TSC1 or TSC2 inactivation, we also performed massively parallel sequencing of these loci. Nineteen (19) of 34 (56%) samples had mutations in TSC2, 10 (29%) had mutations in TSC1, while 5 (15%) had no mutation identified in TSC1/TSC2. The majority of these samples had loss of heterozygosity in the same gene in which the mutation was identified. These results significantly extend previous studies, and in agreement with the Knudson two hit mechanism indicate that biallelic alterations in TSC2 and less commonly, TSC1 are consistently seen in SEGAs.
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Affiliation(s)
- Anika Bongaarts
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Krinio Giannikou
- Division of Pulmonary and Critical Care Medicine and of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Roy J. Reinten
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jasper J. Anink
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - James D. Mills
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Floor E. Jansen
- Department of Pediatric Neurology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - G.M Wim Spliet
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Willfred F.A. den Dunnen
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Roland Coras
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Ingmar Blümcke
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Werner Paulus
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - Theresa Scholl
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
| | - Martha Feucht
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
| | - Sergiusz Jozwiak
- Department of Child Neurology, Medical University of Warsaw, Warsaw, Poland
| | | | | | - Flavio Giordano
- Department of Neurosurgery, Anna Meyer Children's Hospital, Florence, Italy
| | - Lorenzo Genitori
- Department of Neurosurgery, Anna Meyer Children's Hospital, Florence, Italy
| | - Figen Söylemezoğlu
- Department of Pathology, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - José Pimentel
- Department of Neurology, Hospital de Santa Maria, Lisbon, Portugal
| | - Mark Nellist
- Department of Clinical Genetics, Erasmus Medical Centre, Rotterdam, The Netherlands
| | | | - Anwesha Nag
- Center for Cancer Genome Discovery, Dana Farber Cancer Institute, Boston, Massachusetts, USA
| | - Angelika Mühlebner
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
| | - David J. Kwiatkowski
- Division of Pulmonary and Critical Care Medicine and of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN), The Netherlands
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
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17
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Lascano AM, Korff CM, Picard F. Seizures and Epilepsies due to Channelopathies and Neurotransmitter Receptor Dysfunction: A Parallel between Genetic and Immune Aspects. Mol Syndromol 2016; 7:197-209. [PMID: 27781030 DOI: 10.1159/000447707] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Despite intensive research activity leading to many important discoveries, the pathophysiological mechanisms underlying seizures and epilepsy remain poorly understood. An important number of specific gene defects have been related to various forms of epilepsies, and autoimmunity and epilepsy have been associated for a long time. Certain central nervous system proteins have been involved in epilepsy or acute neurological diseases with seizures either due to underlying gene defects or immune dysfunction. Here, we focus on 2 of them that have been the object of particular attention and in-depth research over the past years: the N-methyl-D-aspartate receptor and the leucin-rich glioma-inactivated protein 1 (LGI1). We also describe illustrative examples of situations in which genetics and immunology meet in the complex pathways that underlie seizures and epilepsy.
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Affiliation(s)
- Agustina M Lascano
- EEG and Epilepsy Exploration Unit, University Hospitals Geneva, Geneva, Switzerland
| | - Christian M Korff
- Pediatric Neurology Unit, Child and Adolescent Department, University Hospitals Geneva, Geneva, Switzerland
| | - Fabienne Picard
- EEG and Epilepsy Exploration Unit, University Hospitals Geneva, Geneva, Switzerland
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18
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Metabotropic glutamate receptor 5 – a promising target in drug development and neuroimaging. Eur J Nucl Med Mol Imaging 2016; 43:1151-70. [DOI: 10.1007/s00259-015-3301-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 12/22/2015] [Indexed: 10/22/2022]
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19
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Abstract
Epilepsy develops in more than 70-90% of oligodendroglial tumors and represents a favorable indicator for long-term survival if present as the first clinical sign. Presence of IDH1 mutation is frequently associated with seizures in oligodendrogliomas, next to alterations of glutamate and GABA metabolism in the origin of glioma-associated epilepsy. Treatment by surgery or radiotherapy results in seizure freedom in about two-thirds of patients, and chemotherapy to a seizure reduction in about 50%. Symptomatic anticonvulsive therapy with levetiracetam and valproic acid as monotherapy are both evidence-based drugs for the partial epilepsies, and their effective use in brain tumors is supported by a large amount of additional data. Pharmacoresistance against anticonvulsants is more prevalent among oligodendrogliomas, occurring in about 40% despite polytherapy with two anticonvulsants or more. Toxic signs of anticonvulsants in brain tumors involve cognition, bone marrow and skin. Previous neurosurgery, radiation therapy or chemotherapy add to the risks of cognitive dysfunction.
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Affiliation(s)
- Melissa Kerkhof
- Department of Neurology, Medical Center The Hague, The Netherlands
| | - Christa Benit
- Department of Neurology, Medical Center The Hague, The Netherlands
| | | | - Charles J Vecht
- Service Neurologie Mazarin, GH Pitié-Salpêtrière, Paris, France
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20
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Kotajima-Murakami H, Sato A, Ikeda K. [Pathology and treatment of autism spectrum disorders]. Nihon Yakurigaku Zasshi 2015; 145:193-200. [PMID: 25864830 DOI: 10.1254/fpj.145.193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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21
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Zantomio D, Chana G, Laskaris L, Testa R, Everall I, Pantelis C, Skafidas E. Convergent evidence for mGluR5 in synaptic and neuroinflammatory pathways implicated in ASD. Neurosci Biobehav Rev 2015; 52:172-7. [PMID: 25704074 DOI: 10.1016/j.neubiorev.2015.02.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 01/25/2015] [Accepted: 02/07/2015] [Indexed: 01/05/2023]
Abstract
The pathogenesis of Autism Spectrum Disorder (ASD), a serious neurodevelopmental disorder, is poorly understood. We review evidence for alterations in glutamatergic signalling in the aetiology of ASD, with a focus on the metabotropic glutamate receptor-5 (mGluR5). mGluR5 signalling is important for synapse formation, neuroplasticity and long term potentiation as well as neuroprotection and has been shown to have a regulatory role in neuroinflammation. Evidence for neuroinflammation in ASD is supported by increase in pro-inflammatory cytokines in the blood and cerebrospinal fluid (CSF) and increased number and activation of microglia in postmortem dorsolateral prefrontal cortex (DLPFC). mGlur5 signalling has also been shown to downregulate microglial activation. Therefore, we focus on mGluR5 as a potential unifying explanation for synapse alteration and neuroinflammation seen in ASD. Data from mGluR5 knockout mouse models, and syndromic and non syndromic forms of ASD are discussed in relation to how alterations in mGluR5 are associated with ASD symptoms. This review supports altered mGluR5 functioning as a convergent point in ASD pathogenesis and indicates more research is warranted into mGluR5 as a potential therapeutic target.
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Affiliation(s)
- Daniela Zantomio
- Department of Haematology, Austin Health, Heidelberg, VIC, Australia; Centre for Neural Engineering, The University of Melbourne, Parkville, Victoria, Australia
| | - Gursharan Chana
- Centre for Neural Engineering, The University of Melbourne, Parkville, Victoria, Australia; Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia; The Florey Institute of Neuroscience and Mental Health, Australia
| | - Liliana Laskaris
- Centre for Neural Engineering, The University of Melbourne, Parkville, Victoria, Australia; Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia
| | - Renee Testa
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne & Melbourne Health, Parkville, Victoria, Australia; Department of Psychology, Monash University, Clayton, Vic, Australia
| | - Ian Everall
- Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia; The Florey Institute of Neuroscience and Mental Health, Australia
| | - Christos Pantelis
- Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia; Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne & Melbourne Health, Parkville, Victoria, Australia; The Florey Institute of Neuroscience and Mental Health, Australia
| | - Efstratios Skafidas
- Centre for Neural Engineering, The University of Melbourne, Parkville, Victoria, Australia; Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia; The Florey Institute of Neuroscience and Mental Health, Australia; Centre for Integrative Brain Function, Australia.
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22
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Aronica E, Crino PB. Epilepsy related to developmental tumors and malformations of cortical development. Neurotherapeutics 2014; 11:251-68. [PMID: 24481729 PMCID: PMC3996119 DOI: 10.1007/s13311-013-0251-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Structural abnormalities of the brain are increasingly recognized in patients with neurodevelopmental delay and intractable focal epilepsies. The access to clinically well-characterized neurosurgical material has provided a unique opportunity to better define the neuropathological, neurochemical, and molecular features of epilepsy-associated focal developmental lesions. These studies help to further understand the epileptogenic mechanisms of these lesions. Neuropathological evaluation of surgical specimens from patients with epilepsy-associated developmental lesions reveals two major pathologies: focal cortical dysplasia and low-grade developmental tumors (glioneuronal tumors). In the last few years there have been major advances in the recognition of a wide spectrum of developmental lesions associated with a intractable epilepsy, including cortical tubers in patients with tuberous sclerosis complex and hemimegalencephaly. As an increasing number of entities are identified, the development of a unified and comprehensive classification represents a great challenge and requires continuous updates. The present article reviews current knowledge of molecular pathogenesis and the pathophysiological mechanisms of epileptogenesis in this group of developmental disorders. Both emerging neuropathological and basic science evidence will be analyzed, highlighting the involvement of different, but often converging, pathogenetic and epileptogenic mechanisms, which may create the basis for new therapeutic strategies in these disorders.
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Affiliation(s)
- Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105, AZ, Amsterdam, The Netherlands,
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23
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D'Antoni S, Spatuzza M, Bonaccorso CM, Musumeci SA, Ciranna L, Nicoletti F, Huber KM, Catania MV. Dysregulation of group-I metabotropic glutamate (mGlu) receptor mediated signalling in disorders associated with Intellectual Disability and Autism. Neurosci Biobehav Rev 2014; 46 Pt 2:228-41. [PMID: 24548786 DOI: 10.1016/j.neubiorev.2014.02.003] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 01/13/2014] [Accepted: 02/06/2014] [Indexed: 12/11/2022]
Abstract
Activation of group-I metabotropic glutamate receptors, mGlu1 and mGlu5, triggers a variety of signalling pathways in neurons and glial cells, which are differently implicated in synaptic plasticity. The earliest and much of key studies discovered abnormal mGlu5 receptor function in Fragile X syndrome (FXS) mouse models which then motivated more recent work that finds mGlu5 receptor dysfunction in related disorders such as intellectual disability (ID), obsessive-compulsive disorder (OCD) and autism. Therefore, mGlu1/5 receptor dysfunction may represent a common aetiology of these complex diseases. Furthermore, many studies have focused on dysregulation of mGlu5 signalling to synaptic protein synthesis. However, emerging evidence finds abnormal mGlu5 receptor interactions with its scaffolding proteins in FXS which results in mGlu5 receptor dysfunction and phenotypes independent of signalling to protein synthesis. Finally, both an increased and reduced mGlu5 functioning seem to be associated with ID and autism spectrum disorders, with important consequences for potential treatment of these developmental disorders.
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Affiliation(s)
- Simona D'Antoni
- Institute of Neurological Sciences, the National Research Council of Italy (CNR), Catania, Italy
| | - Michela Spatuzza
- Institute of Neurological Sciences, the National Research Council of Italy (CNR), Catania, Italy
| | | | | | - Lucia Ciranna
- Department of Biomedical Sciences, section of Physiology, University of Catania, Italy
| | - Ferdinando Nicoletti
- IRCCS Neuromed, Pozzilli (IS), Italy; University of Rome La Sapienza, Rome, Italy
| | - Kimberly M Huber
- University of Texas Southwestern Medical Center, Department of Neuroscience, Dallas, TX 75390-9111, USA
| | - Maria Vincenza Catania
- Institute of Neurological Sciences, the National Research Council of Italy (CNR), Catania, Italy; IRCCS Oasi Maria SS, Troina (EN), Italy.
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Potter WB, Basu T, O'Riordan KJ, Kirchner A, Rutecki P, Burger C, Roopra A. Reduced juvenile long-term depression in tuberous sclerosis complex is mitigated in adults by compensatory recruitment of mGluR5 and Erk signaling. PLoS Biol 2013; 11:e1001627. [PMID: 23966835 PMCID: PMC3742461 DOI: 10.1371/journal.pbio.1001627] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 07/05/2013] [Indexed: 02/07/2023] Open
Abstract
A mouse model of the human genetic disorder tuberous sclerosis complex fails to undergo developmental down-regulation of mGluR5 expression and activation of Erk signaling, probably contributing to the aberrant plasticity and epilepsy in this disease. Tuberous sclerosis complex (TSC) is a multisystem genetic disease that manifests with mental retardation, tumor formation, autism, and epilepsy. Heightened signaling through the mammalian target of rapamycin (mTOR) pathway is involved in TSC pathology, however it remains unclear how other signaling pathways are perturbed and contribute to disease symptoms. Reduced long-term depression (LTD) was recently reported in TSC mutant mice. We find that although reduced LTD is a feature of the juvenile mutant hippocampus, heightened expression of metabotropic glutamate receptor 5 and constitutively activated Erk signaling in the adult hippocampus drives wild-type levels of LTD. Increased mGluR5 and Erk results in a novel mTOR-independent LTD in CA1 hippocampus of adult mice, and contributes to the development of epileptiform bursting activity in the TSC2+/− CA3 region of the hippocampus. Inhibition of mGluR5 or Erk signaling restores appropriate mTOR-dependence to LTD, and significantly reduces epileptiform bursting in TSC2+/− hippocampal slices. We also report that adult TSC2+/− mice exhibit a subtle perseverative behavioral phenotype that is eliminated by mGluR5 antagonism. These findings highlight the potential of modulating the mGluR5-Erk pathway in a developmental stage-specific manner to treat TSC. Tuberous sclerosis complex (TSC) is a genetic disorder that afflicts around 1 in 6,000 people and results from a mutation in one of two genes, TSC1 or TSC2. TSC patients suffer a number of neuronal symptoms including various degrees of autism, mental retardation, and epilepsy, the latter found in more than 80% of cases within the first year of life. In the TSC mutant mice that are used to model the disease, a region of the brain called the hippocampus fails to undergo long-term depression (LTD), a neuronal process that is important for learning and memory. We find that while this is the case in juvenile mutant mice, adult mice appear to have fixed this deficit. The “fix” involves the ramping up of signaling pathways involving mGluR5 and Erk. Although increased mGluR5 and Erk signaling outwardly fixes the problem of diminished LTD in adulthood, it renders the brain insensitive to the cues and inputs that normally work to control LTD. Moreover, the hippocampus in adult TSC mice is prone to seizures and impaired in learning and memory tasks. We find that drugs that target mGluR5 or Erk signaling repair the problems with excitability and learning deficits.
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Affiliation(s)
- Wyatt B. Potter
- Department of Neuroscience, Medical Science Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- Neuroscience Training Program, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Trina Basu
- Department of Neuroscience, Medical Science Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- Neuroscience Training Program, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Kenneth J. O'Riordan
- Department of Neurology, William S. Middleton Memorial VA Hospital and University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Allison Kirchner
- Department of Neuroscience, Medical Science Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Paul Rutecki
- Department of Neurology, William S. Middleton Memorial VA Hospital and University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Corinna Burger
- Department of Neurology, William S. Middleton Memorial VA Hospital and University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Avtar Roopra
- Department of Neuroscience, Medical Science Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- * E-mail:
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Iyer A, Prabowo A, Anink J, Spliet WGM, van Rijen PC, Aronica E. Cell injury and premature neurodegeneration in focal malformations of cortical development. Brain Pathol 2013; 24:1-17. [PMID: 23586324 DOI: 10.1111/bpa.12060] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Accepted: 03/26/2013] [Indexed: 12/17/2022] Open
Abstract
Several lines of evidence suggest that cell injury may occur in malformations of cortical development associated with epilepsy. Moreover, recent studies support the link between neurodevelopmental and neurodegenerative mechanisms. We evaluated a series of focal cortical dysplasia (FCD, n=26; type I and II) and tuberous sclerosis complex (TSC, n=6) cases. Sections were processed for terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick-end labeling (TUNEL) labeling and immunohistochemistry using markers for the evaluation of apoptosis signaling pathways and neurodegeneration-related proteins/pathways. In both FCD II and TSC specimens, we observed significant increases in both TUNEL-positive and caspase-3-positive cells compared with controls and FCD I. Expression of β-amyloid precursor protein was observed in neuronal soma and processes in FCD II and TSC. In these specimens, we also observed an abnormal expression of death receptor-6. Immunoreactivity for phosphorylated tau was only found in older patients with FCD II and TSC. In these cases, prominent nuclear/cytoplasmic p62 immunoreactivity was detected in both dysmorphic neurons and balloon/giant cells. Our data provide evidence of complex, but similar, mechanisms of cell injury in focal malformations of cortical development associated with mammalian target of rapamycin pathway hyperactivation, with prominent induction of apoptosis-signaling pathways and premature activation of mechanisms of neurodegeneration.
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Affiliation(s)
- Anand Iyer
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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Iyer A, van Scheppingen J, Anink J, Milenkovic I, Kovács GG, Aronica E. Developmental patterns of DR6 in normal human hippocampus and in Down syndrome. J Neurodev Disord 2013; 5:10. [PMID: 23618225 PMCID: PMC3666921 DOI: 10.1186/1866-1955-5-10] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 04/04/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Death receptor 6 (DR6) is highly expressed in the human brain: it has been shown to induce axon pruning and neuron death via distinct caspases and to mediate axonal degeneration through binding to N-terminal β amyloid precursor protein (N-APP). METHODS We investigated the expression of DR6 during prenatal and postnatal development in human hippocampus and temporal cortex by immunocytochemistry and Western blot analysis (118 normal human brain specimens; 9 to 41 gestational weeks; 1 day to 7 months postnatally; 3 to 91 years). To investigate the role of N-APP/DR6/caspase 6 pathway in the development of hippocampal Alzheimer's disease (AD)-associated pathology, we examined DR6 immunoreactivity (IR) in the developing hippocampus from patients with Down syndrome (DS; 48 brain specimens; 14 to 41 gestational weeks; 7 days to 8 months postnatally; 15 to 64 years) and in adults with DS and AD. RESULTS DR6 was highly expressed in human adult hippocampus and temporal cortex: we observed consistent similar temporal and spatial expression in both control and DS brain. Western blot analysis of total homogenates of temporal cortex and hippocampus showed developmental regulation of DR6. In the hippocampus, DR6 IR was first apparent in the stratum lacunosum-moleculare at 16 weeks of gestation, followed by stratum oriens, radiatum, pyramidale (CA1 to CA4) and molecular layer of the dentate gyrus between 21 and 23 gestational weeks, reaching a pattern similar to adult hippocampus around birth. Increased DR6 expression in dystrophic neurites was detected focally in a 15-year-old DS patient. Abnormal DR6 expression pattern, with increased expression within dystrophic neurites in and around amyloid plaques was observed in adult DS patients with widespread AD-associated neurodegeneration and was similar to the pattern observed in AD hippocampus. Double-labeling experiments demonstrated the colocalization, in dystrophic neurites, of DR6 with APP. We also observed colocalization with hyper-phosphorylated Tau and with caspase 6 (increased in hippocampus with AD pathology) in plaque-associated dystrophic neurites and within the white matter. CONCLUSIONS These findings demonstrate a developmental regulation of DR6 in human hippocampus and suggest an abnormal activation of the N-APP/DR6/caspase 6 pathway, which can contribute to initiation or progression of hippocampal AD-associated pathology.
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Affiliation(s)
- Anand Iyer
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands
| | - Jackelien van Scheppingen
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands
| | - Jasper Anink
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands
| | - Ivan Milenkovic
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Gabor G Kovács
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands.,SEIN - Stichting Epilepsie Instellingen Nederland, Heemstede, The Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
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Crino PB. Evolving neurobiology of tuberous sclerosis complex. Acta Neuropathol 2013; 125:317-32. [PMID: 23386324 DOI: 10.1007/s00401-013-1085-x] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 01/14/2013] [Accepted: 01/19/2013] [Indexed: 11/30/2022]
Abstract
Over the past decade, there have been numerous advances in our understanding of the molecular pathogenesis of tuberous sclerosis complex (TSC). Following the identification of the TSC1 and TSC2 genes, a link to regulatory control of the mammalian target of rapamycin (mTOR) signaling pathway has paved the way for new therapeutic interventions, and now even approved therapies for TSC. Gene identification has permitted establishment of cell lines and conditional knockout mouse strains to assay how abnormalities in brain structure lead to enhanced excitability, seizures, cognitive disabilities, and other neuropsychological disorders in TSC. Furthermore, work in in vitro systems and analysis of rodent models and human tissue has allowed investigators to study how brain lesions form in TSC. Evolving questions over the next decade include understanding the high clinical variability of TSC, defining why there is a lack of clear genotype-phenotype correlations, and identifying biomarkers for prognosis and stratification. The study of TSC has in many ways reflected a paradigm "bench-to-bedside" success story that serves as a model of many other neurological disorders.
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Affiliation(s)
- Peter B Crino
- Department of Neurology, Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, 6th Floor Medical Education and Research Building, 3500N. Broad Street, Philadelphia, PA 19140-4106, USA.
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Prabowo AS, Iyer AM, Anink JJ, Spliet WGM, van Rijen PC, Aronica E. Differential expression of major histocompatibility complex class I in developmental glioneuronal lesions. J Neuroinflammation 2013; 10:12. [PMID: 23347564 PMCID: PMC3565983 DOI: 10.1186/1742-2094-10-12] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 01/10/2013] [Indexed: 11/21/2022] Open
Abstract
Purpose The expression of the major histocompatibility complex class I (MHC-I) in the brain has received considerable interest not only because of its fundamental role in the immune system, but also for its non-immune functions in the context of activity-dependent brain development and plasticity. Methods In the present study we evaluated the expression and cellular pattern of MHC-I in focal glioneuronal lesions associated with intractable epilepsy. MHC-I expression was studied in epilepsy surgery cases with focal cortical dysplasia (FCD I, n = 6; FCD IIa, n = 6 and FCD IIb, n = 15), tuberous sclerosis complex (TSC, cortical tubers; n = 6) or ganglioglioma (GG; n = 15) using immunocytochemistry. Evaluation of T lymphocytes with granzyme-B+ granules and albumin immunoreactivity was also performed. Results All lesions were characterized by MHC-I expression in blood vessels. Expression in both endothelial and microglial cells as well as in neurons (dysmorphic/dysplastic neurons) was observed in FCD II, TSC and GG cases. We observed perivascular and parenchymal T lymphocytes (CD8+, T-cytotoxic) with granzyme-B+ granules in FCD IIb and TSC specimens. Albumin extravasation, with uptake in astrocytes, was observed in FCD IIb and GG cases. Conclusions Our findings indicate a prominent upregulation of MHC-I as part of the immune response occurring in epileptogenic glioneuronal lesions. In particular, the induction of MHC-I in neuronal cells appears to be a feature of type II FCD, TSC and GG and may represent an important accompanying event of the immune response, associated with blood–brain barrier dysfunction, in these developmental lesions.
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Affiliation(s)
- Avanita S Prabowo
- Department of Neuro Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands.
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Leung HTT, Ring H. Epilepsy in four genetically determined syndromes of intellectual disability. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 2013; 57:3-20. [PMID: 22142420 DOI: 10.1111/j.1365-2788.2011.01505.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
BACKGROUND Epilepsy occurs with increased frequency in people with an intellectual disability (ID) compared to the rest of the population. A variety of research has in recent years shed light on genetic and biochemical aetiologies of epilepsy and, often in a different literature, on syndromes of ID. The aims of this annotation are to review developments in understanding of the pathophysiology of several ID syndromes in which epilepsy is a frequent co-occurrence and to relate these observations to recent advances in understanding of how these pathophysiological disturbances may lead to epilepsy. METHOD The ID syndromes selected for review were fragile X (FXS), Rett (RTT) and Angelman syndromes (AS) and tuberous sclerosis complex (TSC). Epilepsy is a significant aspect of these syndromes and relevant research into the genetic and biochemical pathophysiology of these four ID syndromes may be informative in establishing the association between epilepsy and ID. Employing a structured approach the authors initially searched the PubMed database for large case series describing the characteristics of epilepsy as manifested in these ID syndromes. The criteria for inclusion of the case series in the review were a sample size of greater than 50 and the description of several of the characteristic features of epilepsy, namely prevalence of seizures, age of seizure onset, seizure frequency, seizure semiology, severity and treatment. Following this, studies of the genetic and biochemical pathophysiology of these four ID syndromes were reviewed and the potential relevance of this research in understanding the association with epilepsy highlighted. Findings were considered in a focused manner in terms of effects on excitatory and inhibitory neurotransmitter systems and on glial function. RESULTS Diverse genetic pathologies underlying several ID syndromes can lead to alterations in the functioning of the glutamatergic and GABAergic neurotransmitter systems. The mechanisms involved include transcriptional regulation in RTT, translational regulation in FXS and TSC, and UBE3A-mediated proteolysis in AS. Expression or functioning of receptor subunits, uptake sites and enzymes involved in neurotransmitter metabolism are often affected by these changes, and may lead to modifications in network excitability and neuronal plasticity that may contribute to epileptogenesis and ID. Dysfunction in astrocytes may also contribute to epileptogenesis and ID in FXS, RTT and TSC with potential mechanisms including failure of astrocytic support functions, glial inflammation and homeostatic disturbances that affect the excitability and architecture of neuronal networks. CONCLUSIONS The annotation highlights research describing disturbances in excitatory and inhibitory neurotransmitter systems, neuronal ion channel and glial functions that provide possible explanations for the co-occurrence of seizures within several ID syndromes, in some cases suggesting possible avenues for research into novel therapeutic targets. Phenotypic overlaps between syndromes may also relate to roles for the implicated genes in different disturbances in linked biochemical pathways.
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Affiliation(s)
- H T T Leung
- Christ's College, University of Cambridge, UK
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Dello Russo C, Lisi L, Feinstein DL, Navarra P. mTOR kinase, a key player in the regulation of glial functions: relevance for the therapy of multiple sclerosis. Glia 2012; 61:301-11. [PMID: 23044764 DOI: 10.1002/glia.22433] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 09/06/2012] [Accepted: 09/11/2012] [Indexed: 12/26/2022]
Abstract
The mammalian target of rapamycin (mTOR) is a serine/threonine protein kinase with a central role in the regulation of cell growth and proliferation, and several intracellular processes, such as mRNA transcription and translation, autophagy and cytoskeletal organization. The relevance of this pathway in the regulation of the immune system is well characterized. mTOR is essential for the proper activation and proliferation of effector T cells, restricts the development of regulatory T cells, and downregulates innate immune responses. Recently, a direct role of mTOR in the modulation of glial functions has also been recognized. Data from our group and others support the notion that mTOR is involved in microglial proinflammatory activation. The kinase regulates several intracellular processes in astrocytes, among which the rate of mRNA degradation of the inducible form of NO synthase. Therefore, the inhibition of mTOR kinase activity in glial cells results in anti-inflammatory actions, suggesting possible beneficial effects of mTOR inhibitors (like rapamycin) in the treatment of inflammatory-based pathologies of the central nervous system. In contrast, mTOR plays an important role in the regulation of oligodendrocyte development and myelination process as well as several neuronal functions, which may limit this therapeutic approach. Nevertheless, as reviewed here, there is robust evidence that rapamycin ameliorates the clinical course of both the relapsing-remitting and the chronic experimental autoimmune encephalomyelitis (EAE), and significantly reduces the hyperalgesia observed before clinical development of EAE. These findings may have important clinical implications for the therapy of multiple sclerosis.
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Affiliation(s)
- Cinzia Dello Russo
- Institute of Pharmacology, Catholic University Medical School, Rome, Italy.
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Abstract
Structural abnormalities of the brain are increasingly recognized in patients that suffer from pharmacoresistant focal epilepsies by applying high-resolution imaging techniques. In many of these patients, epilepsy surgery results in control of seizures. Neuropathologically, a broad spectrum of malformations of cortical development (MCD) is observed in respective surgical brain samples. These samples provide a unique basis to further understand underlying pathomechanisms by molecular approaches and develop improved diagnostics and entirely new therapeutic perspectives. Here we provide a comprehensive description of neuropathological findings, available classification systems as well as molecular mechanisms of MCDs. We emphasize the recently published ILEA classification system for focal cortical dysplasias (FCDs), which are now histopathologically distinguished as types I to III. However, this revised classification system represents a major challenge for molecular neuropathologists, as the underlying pathomechanisms in virtually all FCD entities will need to be specified in detail. The fact that only recently, the mammalian target of rapamycin (mTOR)-antagonist Everolimus has been introduced as a treatment of epilepsies in the context of tuberous sclerosis-associated brain lesions is a striking example of a successful translational "bedside to bench and back" approach. Hopefully, the exciting clinico-pathological developments in the field of MCDs will in short term foster further therapeutic breakthroughs for the frequently associated medically refractory epilepsies.
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Affiliation(s)
- Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam
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Wu YL, Wang NN, Gu L, Yang HM, Xia N, Zhang H. The suppressive effect of metabotropic glutamate receptor 5 (mGlu5) inhibition on hepatocarcinogenesis. Biochimie 2012; 94:2366-75. [PMID: 22706282 DOI: 10.1016/j.biochi.2012.06.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 06/04/2012] [Indexed: 01/23/2023]
Abstract
Metabotropic glutamate receptors (mGlus) are G-protein-coupled receptors playing an important role in the central nervous system (CNS). Recently, mGlus have been identified in peripheral tissues, and aberrant expression or inhibition of the receptors functions in the development of certain cancers. However, the correlation of mGlu activity with hepatocellular carcinoma (HCC) remains unknown. In this study, we analyzed the effects of inhibiting mGlu5 activity in hepatocarcinoma cell lines and a xenograft model. Inactivation of mGlu5 with 2-Methyl-6-(phenylethyl)-pyridine (MPEP), a specific antagonist of the receptor, caused inhibition of cell growth, migration, and invasion of HepG2 and Bel-7402 cells, assessed by MTT assay, ATP production, wound healing, and Boyden chamber assay, respectively. Moreover, inhibition of tumor growth and the potential metastasis of hepatocellular carcinoma were also found in nude mice. Furthermore, mGlu5-mediated extracellular signal-regulated kinase (ERK) phosphorylation has been found to be partially involved in cell growth and migration, as detected by stimulation of (S)-3,5-Dihydroxyphenylglycine (DHPG), an agonist of the receptor, and blockage of MPEP and U0126, an inhibitor of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (MEK). These data indicate that inhibiting the activity of mGlu5 has the molecular potential to suppress oncogenic actions by blocking downstream effector molecules. The study suggests that mGlu5 activity may contribute to understanding the development of HCC.
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Affiliation(s)
- Yong Le Wu
- Department of Cell Biology, Municipal Laboratory for Liver Protection and Regulation of Regeneration, Capital Medical University, Beijing 100069, China
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Transient mGlu5R inhibition enhances the survival of granule cell precursors in the neonatal cerebellum. Neuroscience 2012; 219:271-9. [PMID: 22677205 DOI: 10.1016/j.neuroscience.2012.05.064] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 05/28/2012] [Indexed: 12/31/2022]
Abstract
The generation of the most abundant neurons of the cerebellum, the granule cells, relies on a balance between clonal expansion and apoptosis during the first 10 days after birth in the external germinal layer (EGL). The amino acid glutamate controls such critical phases of cell development in other systems through specific receptors such as metabotropic glutamate receptor 5 (mGlu(5)R). However, the function of mGlu(5)Rs on the proliferation and survival of granule cell precursors (GCPs) remains elusive. We found mGlu(5)R mRNA transcripts in EGL using RT-PCR and observed mGlu(5)R-mediated Ca(2+) responses in GCPs in acute slices as early as postnatal day (P) 2-3. Using in vivo injections of the selective non-competitive mGlu(5)R antagonist 2-methyl-6-(phenylethynyl)pyridine (MPEP) in P7-P9 mice, we found a 20% increase in the number of proliferative GCPs labeled at P7 with the S-phase marker bromodeoxyuridine (BrdU), but no increase in cell proliferation examined 2h following a BrdU injection. Furthermore, similar treatments led to a significant 70% decrease in the number of apoptotic GCPs in the EGL as determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. In contrast, in vivo treatment with the mGlu(5)R agonist (RS)-2-chloro-5-hydroxyphenylglycine (CHPG) resulted in a ∼60% increase in the number of TUNEL-labeled GCPs compared to control. These findings identify a unique role for glutamate acting at mGlu(5)Rs as a functional switch regulating GCP survival in the EGL, thus controlling the total number of cerebellar granule cells produced.
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Talos DM, Sun H, Kosaras B, Joseph A, Folkerth RD, Poduri A, Madsen JR, Black PM, Jensen FE. Altered inhibition in tuberous sclerosis and type IIb cortical dysplasia. Ann Neurol 2012; 71:539-51. [PMID: 22447678 PMCID: PMC3334406 DOI: 10.1002/ana.22696] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Revised: 11/17/2011] [Accepted: 12/09/2011] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The most common neurological symptom of tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD) is early life refractory epilepsy. As previous studies have shown enhanced excitatory glutamatergic neurotransmission in TSC and FCD brains, we hypothesized that neurons associated with these lesions may also express altered γ-aminobutyric acid (GABA)(A) receptor (GABA(A)R)-mediated inhibition. METHODS Expression of the GABA(A)R subunits α1 and α4, and the Na(+)-K(+)-2Cl(-) (NKCC1) and the K(+)-Cl(-) (KCC2) transporters, in human TSC and FCD type II specimens were analyzed by Western blot and double label immunocytochemistry. GABA(A) R responses in dysplastic neurons from a single case of TSC were measured by perforated patch recording and compared to normal-appearing cortical neurons from a non-TSC epilepsy case. RESULTS TSC and FCD type IIb lesions demonstrated decreased expression of GABA(A)R α1, and increased NKCC1 and decreased KCC2 levels. In contrast, FCD type IIa lesions showed decreased α4, and increased expression of both NKCC1 and KCC2 transporters. Patch clamp recordings from dysplastic neurons in acute slices from TSC tubers demonstrated excitatory GABA(A)R responses that were significantly attenuated by the NKCC1 inhibitor bumetanide, in contrast to hyperpolarizing GABA(A)R-mediated currents in normal neurons from non-TSC cortical slices. INTERPRETATION Expression and function of GABA(A)Rs in TSC and FCD type IIb suggest the relative benzodiazepine insensitivity and more excitatory action of GABA compared to FCD type IIa. These factors may contribute to resistance of seizure activity to anticonvulsants that increase GABAergic function, and may justify add-on trials of the NKCC1 inhibitor bumetanide for the treatment of TSC and FCD type IIb-related epilepsy.
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Affiliation(s)
- Delia M. Talos
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Hongyu Sun
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Bela Kosaras
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | | | - Rebecca D. Folkerth
- Department of Pathology (Neuropathology), Children’s Hospital Boston
- Department of Pathology, Brigham and Women’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Annapurna Poduri
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Joseph R. Madsen
- Department of Neurosurgery, Children’s Hospital Boston
- Department of Neurosurgery, Brigham and Women’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Peter M. Black
- Department of Neurosurgery, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Frances E. Jensen
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
- Program in Neuroscience, Boston, Massachusetts 02115
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Rohof WO, Aronica E, Beaumont H, Troost D, Boeckxstaens GE. Localization of mGluR5, GABAB, GABAA, and cannabinoid receptors on the vago-vagal reflex pathway responsible for transient lower esophageal sphincter relaxation in humans: an immunohistochemical study. Neurogastroenterol Motil 2012; 24:383-e173. [PMID: 22256945 DOI: 10.1111/j.1365-2982.2011.01868.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Transient lower esophageal sphincter relaxations (TLESRs) are the predominant mechanisms underlying gastro-esophageal reflux. TLESRs are mediated by a vago-vagal reflex, which can be blocked by interaction with metabotropic Glutamate Receptor 5 (mGluR5), γ-aminobutyric acid type B (GABA(B)), γ-aminobutyric acid type A (GABA(A)), and cannabinoid (CB) receptors. However, the distribution of these receptors in the neural pathway underlying the triggering of TLESRs has not been evaluated in humans. METHODS Using immunohistochemistry, we investigated the distribution of mGluR5, GABA(A), GABA(B), CB1, and CB2 receptors in the human nodose ganglion, the brain stem, and the myenteric plexus of the esophagus. KEY RESULTS MGluR5, GABA(B), CB1, and CB2 receptors are abundantly expressed in neurons of the myenteric plexus of the LES, nodose ganglion cell bodies and nerve fibers, the dorsal motor nucleus, and nucleus of the solitary tract in the brain stem. GABA(A) receptors are expressed in the same regions except in the nodose ganglion and myenteric plexus of the LES. CONCLUSIONS & INFERENCES Human mGluR5, GABA(A,B), and CB(1,2) receptors are abundantly expressed along the vago-vagal neural pathway and involved in the triggering of TLESRs. These findings are not only in line with the central side effects observed during treatment with reflux inhibitors such as GABA(B) receptor agonists and mGluR5 antagonists, but also suggest that peripherally acting compounds may be effective.
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Affiliation(s)
- W O Rohof
- Department of Gastroenterology, Academic Medical Center, Amsterdam, The Netherlands
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Abstract
Tuberous Sclerosis Complex (TSC) is an autosomal dominant multisystem disorder, characterized by the presence of hamartomatous lesions involving different organ systems, including the brain. Epilepsy is the most common presenting symptom, representing a major source of morbidity and mortality. Despite multiple antiepileptic drug combinations, in about two thirds of cases the patients present high-frequency drug-resistant epilepsy, and nonpharmacologic options may be considered. The aim of this work was to point out the current knowledge on epileptogenesis in TSC, the available medical therapies and diagnostic tools, and possible surgical strategies, with the intent to better understand the actual difficulties in controlling seizures and the results reported in the literature. There is also a section dedicated to the common association with cognitive impairment and the role of epilepsy control on its outcome.
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Affiliation(s)
- Federica Novegno
- Department of Pediatric Neurosurgery, Catholic University Medical School, Rome, Italy.
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37
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Chévere-Torres I, Kaphzan H, Bhattacharya A, Kang A, Maki JM, Gambello MJ, Arbiser JL, Santini E, Klann E. Metabotropic glutamate receptor-dependent long-term depression is impaired due to elevated ERK signaling in the ΔRG mouse model of tuberous sclerosis complex. Neurobiol Dis 2011; 45:1101-10. [PMID: 22198573 DOI: 10.1016/j.nbd.2011.12.028] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 11/08/2011] [Accepted: 12/08/2011] [Indexed: 11/28/2022] Open
Abstract
Tuberous sclerosis complex (TSC) and fragile X syndrome (FXS) are caused by mutations in negative regulators of translation. FXS model mice exhibit enhanced metabotropic glutamate receptor-dependent long-term depression (mGluR-LTD). Therefore, we hypothesized that a mouse model of TSC, ΔRG transgenic mice, also would exhibit enhanced mGluR-LTD. We measured the impact of TSC2-GAP mutations on the mTORC1 and ERK signaling pathways and protein synthesis-dependent hippocampal synaptic plasticity in ΔRG transgenic mice. These mice express a dominant/negative TSC2 that binds to TSC1, but has a deletion and substitution mutation in its GAP-domain, resulting in inactivation of the complex. Consistent with previous studies of several other lines of TSC model mice, we observed elevated S6 phosphorylation in the brains of ΔRG mice, suggesting upregulated translation. Surprisingly, mGluR-LTD was not enhanced, but rather was impaired in the ΔRG transgenic mice, indicating that TSC and FXS have divergent synaptic plasticity phenotypes. Similar to patients with TSC, the ΔRG transgenic mice exhibit elevated ERK signaling. Moreover, the mGluR-LTD impairment displayed by the ΔRG transgenic mice was rescued with the MEK-ERK inhibitor U0126. Our results suggest that the mGluR-LTD impairment observed in ΔRG mice involves aberrant TSC1/2-ERK signaling.
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Feliciano D, Bordey A. Un modèle murin de sclérose tubéreuse de Bourneville pour comprendre le processus d’épilepsie associé auxtuberscorticaux. Med Sci (Paris) 2011; 27:328-30. [DOI: 10.1051/medsci/2011273328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Feliciano DM, Su T, Lopez J, Platel JC, Bordey A. Single-cell Tsc1 knockout during corticogenesis generates tuber-like lesions and reduces seizure threshold in mice. J Clin Invest 2011; 121:1596-607. [PMID: 21403402 DOI: 10.1172/jci44909] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 01/26/2011] [Indexed: 11/17/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by mutations in Tsc1 or Tsc2 that lead to mammalian target of rapamycin (mTOR) hyperactivity. Patients with TSC suffer from intractable seizures resulting from cortical malformations known as tubers, but research into how these tubers form has been limited because of the lack of an animal model. To address this limitation, we used in utero electroporation to knock out Tsc1 in selected neuronal populations in mice heterozygous for a mutant Tsc1 allele that eliminates the Tsc1 gene product at a precise developmental time point. Knockout of Tsc1 in single cells led to increased mTOR activity and soma size in the affected neurons. The mice exhibited white matter heterotopic nodules and discrete cortical tuber-like lesions containing cytomegalic and multinucleated neurons with abnormal dendritic trees resembling giant cells. Cortical tubers in the mutant mice did not exhibit signs of gliosis. Furthermore, phospho-S6 immunoreactivity was not upregulated in Tsc1-null astrocytes despite a lower seizure threshold. Collectively, these data suggest that a double-hit strategy to eliminate Tsc1 in discrete neuronal populations generates TSC-associated cortical lesions, providing a model to uncover the mechanisms of lesion formation and cortical hyperexcitability. In addition, the absence of glial reactivity argues against a contribution of astrocytes to lesion-associated hyperexcitability.
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Affiliation(s)
- David M Feliciano
- Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut 06520-8082, USA
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40
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Boer K, Spliet W, van Rijen P, Jansen F, Aronica E. Expression patterns of AMOG in developing human cortex and malformations of cortical development. Epilepsy Res 2010; 91:84-93. [DOI: 10.1016/j.eplepsyres.2010.06.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 06/13/2010] [Accepted: 06/29/2010] [Indexed: 10/19/2022]
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41
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Boer K, Encha-Razavi F, Sinico M, Aronica E. Differential distribution of group I metabotropic glutamate receptors in developing human cortex. Brain Res 2010; 1324:24-33. [DOI: 10.1016/j.brainres.2010.02.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 01/21/2010] [Accepted: 02/03/2010] [Indexed: 10/19/2022]
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Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder that results from mutations in the TSC1 or TSC2 genes and is associated with hamartoma formation in multiple organ systems. The neurological manifestations of TSC are particularly challenging and include infantile spasms, intractable epilepsy, cognitive disabilities, and autism. Progress over the past 15 years has demonstrated that the TSC1 or TSC2 encoded proteins modulate cell function via the mTOR signaling cascade and serve as keystones in regulating cell growth and proliferation. The mTOR pathway provides an intersection for an intricate network of protein cascades that respond to cellular nutrition, energy levels, and growth-factor stimulation. In the brain, TSC1 and TSC2 have been implicated in cell body size, dendritic arborization, axonal outgrowth and targeting, neuronal migration, cortical lamination, and spine formation. Antagonism of the mTOR pathway with rapamycin and related compounds may provide new therapeutic options for TSC patients.
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Affiliation(s)
- Ksenia A Orlova
- Departments of Neurology and Neuroscience, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
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Aronica E, Fluiter K, Iyer A, Zurolo E, Vreijling J, van Vliet EA, Baayen JC, Gorter JA. Expression pattern of miR-146a, an inflammation-associated microRNA, in experimental and human temporal lobe epilepsy. Eur J Neurosci 2010; 31:1100-7. [PMID: 20214679 DOI: 10.1111/j.1460-9568.2010.07122.x] [Citation(s) in RCA: 249] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Increasing evidence supports the involvement of inflammatory and immune processes in temporal lobe epilepsy (TLE). MicroRNAs (miRNA) represent small regulatory RNA molecules that have been shown to act as negative regulators of gene expression controlling different biological processes, including immune-system homeostasis and function. We investigated the expression and cellular distribution of miRNA-146a (miR-146a) in a rat model of TLE as well as in human TLE. miR-146a analysis in rat hippocampus was performed by polymerase chain reaction and immunocytochemistry at 1 week and 3-4 months after induction of status epilepticus (SE). Prominent upregulation of miR-146a activation was evident at 1 week after SE and persisted in the chronic phase. The miR-146a expression was confirmed to be present in reactive astrocytes. In human TLE with hippocampal sclerosis, increased astroglial expression of miR-146a was observed mainly in regions where neuronal cell loss and reactive gliosis occurred. The increased and persistent expression of miR-146a in reactive astrocytes supports the possible involvement of miRNAs in the modulation of the astroglial inflammatory response occurring in TLE and provides a target for future studies aimed at developing strategies against pro-epileptogenic inflammatory signalling.
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Affiliation(s)
- E Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, The Netherlands.
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44
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Boer K, Crino PB, Gorter JA, Nellist M, Jansen FE, Spliet WGM, van Rijen PC, Wittink FRA, Breit TM, Troost D, Wadman WJ, Aronica E. Gene expression analysis of tuberous sclerosis complex cortical tubers reveals increased expression of adhesion and inflammatory factors. Brain Pathol 2009; 20:704-19. [PMID: 19912235 DOI: 10.1111/j.1750-3639.2009.00341.x] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cortical tubers in patients with tuberous sclerosis complex are associated with disabling neurological manifestations, including intractable epilepsy. While these malformations are believed to result from the effects of TSC1 or TSC2 gene mutations, the molecular mechanisms leading to tuber formation, as well as the onset of seizures, remain largely unknown. We used the Affymetrix Gene Chip platform to provide the first genome-wide investigation of gene expression in surgically resected tubers, compared with histological normal perituberal tissue from the same patients or autopsy control tissue. We identified 2501 differentially expressed genes in cortical tubers compared with autopsy controls. Expression of genes associated with cell adhesion, for example, VCAM1, integrins and CD44, or with the inflammatory response, including complement factors, serpinA3, CCL2 and several cytokines, was increased in cortical tubers, whereas genes related to synaptic transmission, for example, the glial glutamate transporter GLT-1, and voltage-gated channel activity, exhibited lower expression. Gene expression in perituberal cortex was distinct from autopsy control cortex suggesting that even in the absence of tissue pathology the transcriptome is altered in TSC. Changes in gene expression yield insights into new candidate genes that may contribute to tuber formation or seizure onset, representing new targets for potential therapeutic development.
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Affiliation(s)
- Karin Boer
- Department of (Neuro)Pathology, Academic Medical Center, Amsterdam, The Netherlands
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D’Arcangelo G. From human tissue to animal models: Insights into the pathogenesis of cortical dysplasia. Epilepsia 2009; 50 Suppl 9:28-33. [DOI: 10.1111/j.1528-1167.2009.02290.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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46
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Napolioni V, Moavero R, Curatolo P. Recent advances in neurobiology of Tuberous Sclerosis Complex. Brain Dev 2009; 31:104-13. [PMID: 19028034 DOI: 10.1016/j.braindev.2008.09.013] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Accepted: 09/26/2008] [Indexed: 10/21/2022]
Abstract
Tuberous Sclerosis Complex (TSC) is a multisystem genetic disorder with variable phenotypic expression, due to a mutation in one of the two genes, TSC1 and TSC2, and a subsequent hyperactivation of the downstream mTOR pathway, resulting in increased cell growth and proliferation. The central nervous system is consistently involved in TSC, with 90% of individuals affected showing structural abnormalities, and almost all having some degree of CNS clinical manifestations, including seizures, cognitive impairment and behavioural problems. TSC is proving to be a particularly informative model for studying contemporary issues in developmental neurosciences. Recent advances in the neurobiology of TSC from molecular biology, molecular genetics, and animal model studies provide a better understanding of the pathogenesis of TSC-related neurological symptoms. Rapamycin normalizes the dysregulated mTOR pathway, and recent clinical trials have demonstrated its efficacy in various TSC manifestations, suggesting the possibility that rapamycin may have benefit in the treatment of TSC brain disease.
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Affiliation(s)
- Valerio Napolioni
- Laboratory of Human Genetics, Department of Molecular, Cellular and Animal Biology, University of Camerino, Camerino, Italy
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