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Mardones MD, Rostam KD, Nickerson MC, Gupta K. Canonical Wnt activator Chir99021 prevents epileptogenesis in the intrahippocampal kainate mouse model of temporal lobe epilepsy. Exp Neurol 2024; 376:114767. [PMID: 38522659 PMCID: PMC11058011 DOI: 10.1016/j.expneurol.2024.114767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 02/29/2024] [Accepted: 03/21/2024] [Indexed: 03/26/2024]
Abstract
The Wnt signaling pathway mediates the development of dentate granule cell neurons in the hippocampus. These neurons are central to the development of temporal lobe epilepsy and undergo structural and physiological remodeling during epileptogenesis, which results in the formation of epileptic circuits. The pathways responsible for granule cell remodeling during epileptogenesis have yet to be well defined, and represent therapeutic targets for the prevention of epilepsy. The current study explores Wnt signaling during epileptogenesis and for the first time describes the effect of Wnt activation using Wnt activator Chir99021 as a novel anti-epileptogenic therapeutic approach. Focal mesial temporal lobe epilepsy was induced by intrahippocampal kainate (IHK) injection in wild-type and POMC-eGFP transgenic mice. Wnt activator Chir99021 was administered daily, beginning 3 h after seizure induction, and continued up to 21-days. Immature granule cell morphology was quantified in the ipsilateral epileptogenic zone and the contralateral peri-ictal zone 14 days after IHK, targeting the end of the latent period. Bilateral hippocampal electrocorticographic recordings were performed for 28-days, 7-days beyond treatment cessation. Hippocampal behavioral tests were performed after completion of Chir99021 treatment. Consistent with previous studies, IHK resulted in the development of epilepsy after a 14 day latent period in this well-described mouse model. Activation of the canonical Wnt pathway with Chir99021 significantly reduced bilateral hippocampal seizure number and duration. Critically, this effect was retained after treatment cessation, suggesting a durable antiepileptogenic change in epileptic circuitry. Morphological analyses demonstrated that Wnt activation prevented pathological remodeling of the primary dendrite in both the epileptogenic zone and peri-ictal zone, changes in which may serve as a biomarker of epileptogenesis and anti-epileptogenic treatment response in pre-clinical studies. These findings were associated with improved object location memory with Chir99021 treatment after IHK. This study provides novel evidence that canonical Wnt activation prevents epileptogenesis in the IHK mouse model of mesial temporal lobe epilepsy, preventing pathological remodeling of dentate granule cells. Wnt signaling may therefore play a key role in mesial temporal lobe epileptogenesis, and Wnt modulation may represent a novel therapeutic strategy in the prevention of epilepsy.
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Affiliation(s)
- Muriel D Mardones
- Indiana University, Stark Neurosciences Research Institute, W 15th St, Indianapolis, IN 46202, United States of America; Indiana University, Department of Neurosurgery, W 16th St, Indianapolis, IN 46202, United States of America.
| | - Kevin D Rostam
- Indiana University, Stark Neurosciences Research Institute, W 15th St, Indianapolis, IN 46202, United States of America.
| | - Margaret C Nickerson
- Indiana University, Stark Neurosciences Research Institute, W 15th St, Indianapolis, IN 46202, United States of America.
| | - Kunal Gupta
- Medical College of Wisconsin, Department of Neurosurgery, 8701 Watertown Plank Rd, Milwaukee, WI 53226, United States of America; Medical College of Wisconsin, Neuroscience Research Center, 8701 Watertown Plank Rd, Milwaukee, WI 53226, United States of America; Indiana University, Stark Neurosciences Research Institute, W 15th St, Indianapolis, IN 46202, United States of America; Indiana University, Department of Neurosurgery, W 16th St, Indianapolis, IN 46202, United States of America.
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2
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Lara MK, Brabec JL, Hernan AE, Scott RC, Tyler AL, Mahoney JM. Network-based analysis predicts interacting genetic modifiers from a meta-mapping study of spike-wave discharge in mice. GENES, BRAIN, AND BEHAVIOR 2024; 23:e12879. [PMID: 38444174 PMCID: PMC10915378 DOI: 10.1111/gbb.12879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 11/29/2023] [Accepted: 12/19/2023] [Indexed: 03/07/2024]
Abstract
Absence seizures are characterized by brief lapses in awareness accompanied by a hallmark spike-and-wave discharge (SWD) electroencephalographic pattern and are common to genetic generalized epilepsies (GGEs). While numerous genes have been associated with increased risk, including some Mendelian forms with a single causal allele, most cases of GGE are idiopathic and there are many unknown genetic modifiers of GGE influencing risk and severity. In a previous meta-mapping study, crosses between transgenic C57BL/6 and C3HeB/FeJ strains, each carrying one of three SWD-causing mutations (Gabrg2tm1Spet(R43Q) , Scn8a8j or Gria4spkw1 ), demonstrated an antagonistic epistatic interaction between loci on mouse chromosomes 2 and 7 influencing SWD. These results implicate universal modifiers in the B6 background that mitigate SWD severity through a common pathway, independent of the causal mutation. In this study, we prioritized candidate modifiers in these interacting loci. Our approach integrated human genome-wide association results with gene interaction networks and mouse brain gene expression to prioritize candidate genes and pathways driving variation in SWD outcomes. We considered candidate genes that are functionally associated with human GGE risk genes and genes with evidence for coding or non-coding allele effects between the B6 and C3H backgrounds. Our analyses output a summary ranking of gene pairs, one gene from each locus, as candidates for explaining the epistatic interaction. Our top-ranking gene pairs implicate microtubule function, cytoskeletal stability and cell cycle regulation as novel hypotheses about the source of SWD variation across strain backgrounds, which could clarify underlying mechanisms driving differences in GGE severity in humans.
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Affiliation(s)
- Montana Kay Lara
- Department of Neurological SciencesUniversity of VermontBurlingtonVermontUSA
| | - Jeffrey L. Brabec
- Department of Neurological SciencesUniversity of VermontBurlingtonVermontUSA
| | - Amanda E. Hernan
- Department of Neurological SciencesUniversity of VermontBurlingtonVermontUSA
- Division of NeuroscienceNemours Children's HealthWilmingtonDelawareUSA
- Department of Psychological and Brain SciencesUniversity of DelawareNewarkDelawareUSA
| | - Rod C. Scott
- Division of NeuroscienceNemours Children's HealthWilmingtonDelawareUSA
- Department of Psychological and Brain SciencesUniversity of DelawareNewarkDelawareUSA
| | | | - J. Matthew Mahoney
- Department of Neurological SciencesUniversity of VermontBurlingtonVermontUSA
- The Jackson LaboratoryBar HarborMaineUSA
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3
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Kim EJ, Lee M, Yum MS. Specific inhibitor of Wnt/beta-catenin pathway can alter behavioral responses in young rats with malformed cortices. Behav Brain Res 2024; 460:114801. [PMID: 38070690 DOI: 10.1016/j.bbr.2023.114801] [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: 08/03/2023] [Revised: 11/24/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023]
Abstract
The Wnt/beta-catenin pathway plays a crucial role in regulating cellular processes and has been implicated in neural activity-dependent learning as well as anxiety. However, the role of this pathway in young children with abnormal cortical development is unknown. Cortical malformations at early development, behavioral abnormalities, and a susceptibility to seizures have been reported in rats prenatally exposed to methylazoxymethanol. In this study, we aimed to investigate whether we could improve the behavioral deficits in young rats with malformed cerebral cortices by modulation of the Wnt/beta-catenin pathway. We found a small molecule Wnt/beta-catenin inhibitor (CWP) that increased exploratory behavior in the open field test (P9, CWP 100 ug treatment, peripheral exploration, P = 0.011) and social behavior test (P12, CWP 250 ug treatment, distance traveled in center, P = 0.033) and decreased anxiety in fear conditioning. However, it did not reduce the susceptibility to seizures. After high dose (250 ug) CWP treatment at P12, phosphocreatine and glutathione (GSH) were decreased in the cortex at P15 (P = 0.021). These findings suggest that the role of Wnt/beta-catenin signaling in exploratory behavior and anxiety during early development warrants further investigation.
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Affiliation(s)
- Eun-Jin Kim
- Department of Pediatrics, University of Ulsan College of Medicine, Seoul 05505, South Korea; Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, South Korea
| | - Minyoung Lee
- Department of Pediatrics, University of Ulsan College of Medicine, Seoul 05505, South Korea; Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, South Korea
| | - Mi-Sun Yum
- Department of Pediatrics, University of Ulsan College of Medicine, Seoul 05505, South Korea; Department of Pediatrics, Asan Medical Center Children's Hospital, 88 Olympic-ro, Songpa-ku, Seoul 05505, South Korea.
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4
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An insight into crosstalk among multiple signaling pathways contributing to epileptogenesis. Eur J Pharmacol 2021; 910:174469. [PMID: 34478688 DOI: 10.1016/j.ejphar.2021.174469] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/16/2021] [Accepted: 08/30/2021] [Indexed: 01/04/2023]
Abstract
Despite the years of research, epilepsy remains uncontrolled in one-third of afflicted individuals and poses a health and economic burden on society. Currently available anti-epileptic drugs mainly target the excitatory-inhibitory imbalance despite targeting the underlying pathophysiology of the disease. Recent research focuses on understanding the pathophysiologic mechanisms that lead to seizure generation and on possible new treatment avenues for preventing epilepsy after a brain injury. Various signaling pathways, including the mechanistic target of rapamycin (mTOR) pathway, mitogen-activated protein kinase (MAP-ERK) pathway, JAK-STAT pathway, wnt/β-catenin signaling, cAMP pathway, and jun kinase pathway, have been suggested to play an essential role in this regard. Recent work suggests that the mTOR pathway intervenes epileptogenesis and proposes that mTOR inhibitors may have antiepileptogenic properties for epilepsy. In the same way, several animal studies have indicated the involvement of the Wnt signaling pathway in neurogenesis and neuronal death induced by seizures in different phases (acute and chronic) of seizure development. Various studies have also documented the activation of JAK-STAT signaling in epilepsy and cAMP involvement in epileptogenesis through CREB (cAMP response element-binding protein). Although studies are there, the mechanism for how components of these pathways mediate epileptogenesis requires further investigation. This review summarises the current role of various signaling pathways involved in epileptogenesis and the crosstalk among them. Furthermore, we will also discuss the mechanical base for the interaction between these pathways and how these interactions could be a new emerging promising target for future epilepsy therapies.
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5
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Chen L, Wang Y, Chen Z. Adult Neurogenesis in Epileptogenesis: An Update for Preclinical Finding and Potential Clinical Translation. Curr Neuropharmacol 2021; 18:464-484. [PMID: 31744451 PMCID: PMC7457402 DOI: 10.2174/1570159x17666191118142314] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 10/31/2019] [Accepted: 11/18/2019] [Indexed: 12/22/2022] Open
Abstract
Epileptogenesis refers to the process in which a normal brain becomes epileptic, and is characterized by hypersynchronous spontaneous recurrent seizures involving a complex epileptogenic network. Current available pharmacological treatment of epilepsy is generally symptomatic in controlling seizures but is not disease-modifying in epileptogenesis. Cumulative evidence suggests that adult neurogenesis, specifically in the subgranular zone of the hippocampal dentate gyrus, is crucial in epileptogenesis. In this review, we describe the pathological changes that occur in adult neurogenesis in the epileptic brain and how adult neurogenesis is involved in epileptogenesis through different interventions. This is followed by a discussion of some of the molecular signaling pathways involved in regulating adult neurogenesis, which could be potential druggable targets for epileptogenesis. Finally, we provide perspectives on some possible research directions for future studies.
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Affiliation(s)
- Liying Chen
- Institute of Pharmacology & Toxicology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Yi Wang
- Institute of Pharmacology & Toxicology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China.,Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Zhong Chen
- Institute of Pharmacology & Toxicology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China.,Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
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6
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Liu Y, Xing H, Yokoi F, Vaillancourt DE, Li Y. Investigating the role of striatal dopamine receptor 2 in motor coordination and balance: Insights into the pathogenesis of DYT1 dystonia. Behav Brain Res 2021; 403:113137. [PMID: 33476687 DOI: 10.1016/j.bbr.2021.113137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 12/29/2020] [Accepted: 01/13/2021] [Indexed: 12/16/2022]
Abstract
DYT1 or DYT-TOR1A dystonia is early-onset, generalized dystonia. Most DYT1 dystonia patients have a heterozygous trinucleotide GAG deletion in DYT1 or TOR1A gene, with a loss of a glutamic acid residue of the protein torsinA. DYT1 dystonia patients show reduced striatal dopamine D2 receptor (D2R) binding activity. We previously reported reduced striatal D2R proteins and impaired corticostriatal plasticity in Dyt1 ΔGAG heterozygous knock-in (Dyt1 KI) mice. It remains unclear how the D2R reduction contributes to the pathogenesis of DYT1 dystonia. Recent knockout studies indicate that D2R on cholinergic interneurons (Chls) has a significant role in corticostriatal plasticity, while D2R on medium spiny neurons (MSNs) plays a minor role. To determine how reduced D2Rs on ChIs and MSNs affect motor performance, we generated ChI- or MSN-specific D2R conditional knockout mice (Drd2 ChKO or Drd2 sKO). The striatal ChIs in the Drd2 ChKO mice showed an increased firing frequency and impaired quinpirole-induced inhibition, suggesting a reduced D2R function on the ChIs. Drd2 ChKO mice had an age-dependent deficient performance on the beam-walking test similar to the Dyt1 KI mice. The Drd2 sKO mice, conversely, had a deficit on the rotarod but not the beam-walking test. Our findings suggest that D2Rs on Chls and MSNs have critical roles in motor control and balance. The similarity of the beam-walking deficit between the Drd2 ChKO and Dyt1 KI mice supports our earlier notion that D2R reduction on striatal ChIs contributes to the pathophysiology and the motor symptoms of DYT1 dystonia.
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Affiliation(s)
- Yuning Liu
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, United States; Genetics Institute, University of Florida, Gainesville, FL, United States
| | - Hong Xing
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, United States
| | - Fumiaki Yokoi
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, United States
| | - David E Vaillancourt
- Department of Applied Physiology and Kinesiology, Biomedical Engineering, and Neurology, University of Florida, Gainesville, FL, United States
| | - Yuqing Li
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, United States; Genetics Institute, University of Florida, Gainesville, FL, United States.
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7
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Insights into Potential Targets for Therapeutic Intervention in Epilepsy. Int J Mol Sci 2020; 21:ijms21228573. [PMID: 33202963 PMCID: PMC7697405 DOI: 10.3390/ijms21228573] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/04/2020] [Accepted: 11/11/2020] [Indexed: 02/06/2023] Open
Abstract
Epilepsy is a chronic brain disease that affects approximately 65 million people worldwide. However, despite the continuous development of antiepileptic drugs, over 30% patients with epilepsy progress to drug-resistant epilepsy. For this reason, it is a high priority objective in preclinical research to find novel therapeutic targets and to develop effective drugs that prevent or reverse the molecular mechanisms underlying epilepsy progression. Among these potential therapeutic targets, we highlight currently available information involving signaling pathways (Wnt/β-catenin, Mammalian Target of Rapamycin (mTOR) signaling and zinc signaling), enzymes (carbonic anhydrase), proteins (erythropoietin, copine 6 and complement system), channels (Transient Receptor Potential Vanilloid Type 1 (TRPV1) channel) and receptors (galanin and melatonin receptors). All of them have demonstrated a certain degree of efficacy not only in controlling seizures but also in displaying neuroprotective activity and in modifying the progression of epilepsy. Although some research with these specific targets has been done in relation with epilepsy, they have not been fully explored as potential therapeutic targets that could help address the unsolved issue of drug-resistant epilepsy and develop new antiseizure therapies for the treatment of epilepsy.
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8
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Lee EC, Hu VW. Phenotypic Subtyping and Re-Analysis of Existing Methylation Data from Autistic Probands in Simplex Families Reveal ASD Subtype-Associated Differentially Methylated Genes and Biological Functions. Int J Mol Sci 2020; 21:E6877. [PMID: 32961747 PMCID: PMC7555936 DOI: 10.3390/ijms21186877] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 09/14/2020] [Accepted: 09/17/2020] [Indexed: 12/27/2022] Open
Abstract
Autism spectrum disorder (ASD) describes a group of neurodevelopmental disorders with core deficits in social communication and manifestation of restricted, repetitive, and stereotyped behaviors. Despite the core symptomatology, ASD is extremely heterogeneous with respect to the severity of symptoms and behaviors. This heterogeneity presents an inherent challenge to all large-scale genome-wide omics analyses. In the present study, we address this heterogeneity by stratifying ASD probands from simplex families according to the severity of behavioral scores on the Autism Diagnostic Interview-Revised diagnostic instrument, followed by re-analysis of existing DNA methylation data from individuals in three ASD subphenotypes in comparison to that of their respective unaffected siblings. We demonstrate that subphenotyping of cases enables the identification of over 1.6 times the number of statistically significant differentially methylated regions (DMR) and DMR-associated genes (DAGs) between cases and controls, compared to that identified when all cases are combined. Our analyses also reveal ASD-related neurological functions and comorbidities that are enriched among DAGs in each phenotypic subgroup but not in the combined case group. Moreover, relational gene networks constructed with the DAGs reveal signaling pathways associated with specific functions and comorbidities. In addition, a network comprised of DAGs shared among all ASD subgroups and the combined case group is enriched in genes involved in inflammatory responses, suggesting that neuroinflammation may be a common theme underlying core features of ASD. These findings demonstrate the value of phenotype definition in methylomic analyses of ASD and may aid in the development of subtype-directed diagnostics and therapeutics.
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Affiliation(s)
| | - Valerie W. Hu
- Department of Biochemistry and Molecular Medicine, The George Washington University, School of Medicine and Health Sciences, Washington, DC 20037, USA;
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9
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Kernohan KD, McBride A, Hartley T, Rojas SK, Dyment DA, Boycott KM, Dyack S. p21 protein-activated kinase 1 is associated with severe regressive autism, and epilepsy. Clin Genet 2019; 96:449-455. [PMID: 31392718 DOI: 10.1111/cge.13618] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 05/08/2019] [Indexed: 01/26/2023]
Abstract
The p21-activated kinase (PAK) family of proteins function as key effectors of RHO family GTPases in mammalian cells to regulate many pathways including Ras/Raf/MEK/ERK and Wnt/β-catenin, amongst others. Here we report an individual with a novel autosomal dominant disorder characterized by severe regressive autism, intellectual disability, and epilepsy. Exome sequencing of the proband and her parents revealed a de novo variant in the PAK1 gene ([NM_001128620] c.362C>T/p.Pro121Leu). Studies in patient cells showed a clear effect on PAK1 protein function, including altered phosphorylation of targets (JNK and ERK), decreased abundance of β-catenin, and concomitant altered expression downstream of these key regulators. Our findings add PAK1 to the list of PAK proteins and kinases which when mutated cause rare genetic diseases.
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Affiliation(s)
- Kristin D Kernohan
- Newborn Screening Ontario, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Arran McBride
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Taila Hartley
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Samantha K Rojas
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
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- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - David A Dyment
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada.,Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Kym M Boycott
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada.,Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Sarah Dyack
- Department of Pediatrics, Dalhousie University and IWK Health Centre, Halifax, Nova Scotia, Canada
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10
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Effects of GLP-1 Receptor Activation on a Pentylenetetrazole-Kindling Rat Model. Brain Sci 2019; 9:brainsci9050108. [PMID: 31091715 PMCID: PMC6562858 DOI: 10.3390/brainsci9050108] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 04/26/2019] [Accepted: 05/06/2019] [Indexed: 12/12/2022] Open
Abstract
Objectives: To study the possible anti-seizure and neuroprotective effect of glucagon like peptide 1 (GLP1) analogue (liraglutide) in a pentylenetetrazole (PTZ) induced kindled rat model and its underlying mechanisms. Methods: Thirty Sprague Dawley rats were allocated into 3 equal groups; i) Normal group: normal rats received normal saline, ii) PTZ (kindling) group: received PTZ (50 mg/Kg intraperitoneally (i.p.)) every other day for 2 weeks and iii) PTZ + GLP1 group: same as the PTZ group but rats received liraglutide (75 µg/kg i.p. daily) for 2 weeks before PTZ injection. Seizure severity score, seizure latency and duration were assessed. Also, the expression of caspase-3 (apoptotic marker) and β-catenin (Wnt pathway) by western blotting, markers of oxidative stress (GSH, CAT and MDA) by biochemical assay and the expression of LC3 (marker of autophagy) and heat shock protein 70 (Hsp70) by immunostaining were assessed in hippocampal regions of brain tissues. Results: PTZ caused a significant increase in Racine score and seizure duration with a significant decrease in seizure latency. These effects were associated with a significant increase in MDA, β-catenin, caspase-3, Hsp70 and LC3 in brain tissues (p < 0.05). Meanwhile, liraglutide treatment caused significant attenuation in PTZ-induced seizures, which were associated with significant improvement in markers of oxidative stress, reduction in LC3, caspase-3 and β-catenin and marked increase in Hsp70 in hippocampal regions (p < 0.05). Conclusion: Activation of GLP1R might have anticonvulsant and neuroprotective effects against PTZ-induced epilepsy. These effects could be due to suppression of oxidative stress, apoptosis and autophagy and upregulation of Hsp70.
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11
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Uncovering the Pharmacological Mechanism of Chaibei Zhixian Decoction on Epilepsy by Network Pharmacology Analysis. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2019; 2019:3104741. [PMID: 31214268 PMCID: PMC6535852 DOI: 10.1155/2019/3104741] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 03/29/2019] [Accepted: 04/21/2019] [Indexed: 02/07/2023]
Abstract
Objective Epilepsy is a neuronal disorder that is characterized by epileptic seizures and linked with abnormal neural functioning in the brain. Traditional Chinese medicine (TCM) formula Chaibei Zhixian decoction (CZD) has been widely used for epilepsy in China while the pharmacological mechanisms are still unclear. In the present study, systematic and comprehensive network pharmacology was utilized for the first time to reveal the potential pharmacological mechanisms of CZD on epilepsy. Methods Traditional Chinese Medicine Systems Pharmacology (TCMSP) database and analysis platform was utilized for the development of an ingredients-targets database. After identifying epileptic targets of CZD, their interaction with other proteins was estimated based on protein-protein interaction network created from STITCH and gene ontology (GO) enrichment analysis utilizing Cytoscape-ClueGO plugin. Results CZD formula was found to have 643 chemical ingredients, and the potential protein targets of these ingredients were 5230, as retrieved from TCMSP database. Twenty-six protein targets were found to be associated with epilepsy. Thirteen hub genes were regulated by CZD in epilepsy, including estradiol, ESR1, ESR2, SRC, CTNNB1, EP300, MAPK1, MAPK3, SP1, BRCA1, NCOA3, CHRM1, and GSK3B. The results of GO terms analysis showed that 8 GO terms were recovered in the form of 3 clusters, including negative regulation of protein kinase B signaling, positive regulation of interleukin-1 production, and microvillus assembly. Conclusions Network pharmacology approach provides better understanding of the underlying pharmacological mechanisms of CZD on epilepsy. Estradiol, ESR1, ESR2, CTNNB1, EP300, MAPK1, MAPK3, BRCA1, and GSK3B are likely to be important molecules regulated by CZD in treatment of epilepsy. Negative regulation of protein kinase B signaling may play vital roles in the treatment of epilepsy by CZD.
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12
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DiNuoscio G, Atit RP. Wnt/β-catenin signaling in the mouse embryonic cranial mesenchyme is required to sustain the emerging differentiated meningeal layers. Genesis 2019; 57:e23279. [PMID: 30615824 DOI: 10.1002/dvg.23279] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 12/03/2018] [Accepted: 12/04/2018] [Indexed: 12/31/2022]
Abstract
Cranial neural crest cells (CNCCs) give rise to cranial mesenchyme (CM) that differentiates into the forebrain meningeal progenitors in the basolateral and apical regions of the head. This occurs in close proximity to the other CNCC-CM-derivatives, such as calvarial bone and dermal progenitors. We found active Wnt signaling transduction in the forebrain meningeal progenitors in basolateral and apical populations and in the non-meningeal CM preceding meningeal differentiation. Here, we dissect the source of Wnt ligand secretion and requirement of Wnt/β-catenin signaling for the lineage selection and early differentiation of the forebrain meninges. We find persistent canonical Wnt/β-catenin signal transduction in the meningeal progenitors in the absence of Wnt ligand secretion in the CM or surface ectoderm, suggesting additional sources of Wnts. Conditional mutants for Wntless and β-catenin in the CM showed that Wnt ligand secretion and Wnt/β-catenin signaling were dispensable for specification and proliferation of early meningeal progenitors. In the absence of β-catenin in the CM, we found diminished laminin matrix and meningeal hypoplasia, indicating a structural and trophic role of mesenchymal β-catenin signaling. This study shows that β-catenin signaling is required in the CM for maintenance and organization of the differentiated meningeal layers in the basolateral and apical populations of embryonic meninges.
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Affiliation(s)
- Gregg DiNuoscio
- Department of Biology, Case Western Reserve University, Cleveland, Ohio
| | - Radhika P Atit
- Department of Biology, Case Western Reserve University, Cleveland, Ohio.,Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio.,Department of Dermatology, Case Western Reserve University, Cleveland, Ohio
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13
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Hussein AM, Eldosoky M, El-Shafey M, El-Mesery M, Ali AN, Abbas KM, Abulseoud OA. Effects of metformin on apoptosis and α-synuclein in a rat model of pentylenetetrazole-induced epilepsy. Can J Physiol Pharmacol 2018; 97:37-46. [PMID: 30308130 DOI: 10.1139/cjpp-2018-0266] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The present study was designed to examine the possible neuroprotective and antiepileptic effects of metformin (Metf) in a rat model of pentylenetetrazole (PTZ)-induced epilepsy and its possible underlying mechanisms. Forty male albino rats were assigned to 4 groups of equal size: (1) normal control (NC) group, (2) Metf group: daily treatment with Metf (200 mg/kg, i.p.) for 2 weeks, (3) PTZ group: treatment with PTZ (50 mg/kg, i.p.) every other day for 2 weeks, and (4) Metf + PTZ group: daily treatment with PTZ and metformin (200 mg/kg, i.p.) for 2 weeks. Administration of PTZ caused a significant increase in seizure score and duration, induced a state of oxidative stress (high malondialdehyde, low reduced glutathione and catalase activity), and led to the upregulation of β-catenin, caspase-3, and its cleavage products, Hsp70 and α-synuclein, in hippocampal regions as well as a significant reduction in seizure latency. While Metf treatment significantly ameliorated PTZ-induced seizures, attenuated oxidative stress, and upregulated α-synuclein and β-catenin expression, it also inhibited caspase-3 activation and the release of the cleavage product and caused more upregulation in Hsp70 expression in hippocampal regions (p < 0.05). In conclusion, the antiepileptic and neuroprotective effects of Metf in PTZ-induced epilepsy might be due to the inhibition of apoptosis, attenuation of oxidative stress and α-synuclein expression, and upregulation of Hsp70.
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Affiliation(s)
- Abdelaziz M Hussein
- a Department of Medical Physiology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Mohamed Eldosoky
- a Department of Medical Physiology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Mohamed El-Shafey
- b Department of Human Anatomy, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Mohamed El-Mesery
- c Department of Biochemistry, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | - Amr N Ali
- d Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Khaled M Abbas
- d Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Osama A Abulseoud
- e Chemistry and Drug Metabolism, IRP, National Institute on Drug Abuse, National Institutes of Health, Biomedical Research Center, Baltimore, MD, USA
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14
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Hodges SL, Lugo JN. Wnt/β-catenin signaling as a potential target for novel epilepsy therapies. Epilepsy Res 2018; 146:9-16. [PMID: 30053675 DOI: 10.1016/j.eplepsyres.2018.07.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 06/28/2018] [Accepted: 07/11/2018] [Indexed: 01/01/2023]
Abstract
Epilepsy is one of the most common neurological disorders, and yet many afflicted individuals are resistant to all available therapeutic treatments. Existing pharmaceutical treatments function primarily to reduce hyperexcitability and prevent seizures, but fail to influence the underlying pathophysiology of the disorder. Recently, research efforts have focused on identifying alternative mechanistic targets for anti-epileptogenic therapies that can prevent the development of chronic epilepsy. The Wnt/β-catenin pathway, one possible target, has been demonstrated to be disrupted in both acute and chronic phases of epilepsy. Wnt/β-catenin signaling can regulate many seizure-induced changes in the brain, including neurogenesis and neuronal death, as well as can influence seizure susceptibility and potentially the development of chronic epilepsy. Several genome-wide studies and in vivo knockout animal models have provided evidence for an association between disrupted Wnt/β-catenin signaling and epilepsy. Furthermore, approved pharmaceutical drugs and other small molecule compounds that target components of the β-catenin destruction complex or antagonize endogenous inhibitors of the pathway have shown to be protective following seizures. However, additional studies are needed to determine the optimal time period in which modulation of the pathway may be most beneficial. Overall, disrupted molecular networks such as Wnt/β-catenin signaling, could be a promising anti-epileptogenic target for future epilepsy therapies.
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Affiliation(s)
- Samantha L Hodges
- Institute of Biomedical Studies, Baylor University, Waco, TX, 76798, USA
| | - Joaquin N Lugo
- Institute of Biomedical Studies, Baylor University, Waco, TX, 76798, USA; Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA; Department of Biology, Baylor University, Waco, TX, 76798, USA.
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15
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Hussein AM, Adel M, El-Mesery M, Abbas KM, Ali AN, Abulseoud OA. l-Carnitine Modulates Epileptic Seizures in Pentylenetetrazole-Kindled Rats via Suppression of Apoptosis and Autophagy and Upregulation of Hsp70. Brain Sci 2018. [PMID: 29538301 PMCID: PMC5870363 DOI: 10.3390/brainsci8030045] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
l-Carnitine is a unique nutritional supplement for athletes that has been recently studied as a potential treatment for certain neuropsychiatric disorders. However, its efficacy in seizure control has not been investigated. Sprague Dawley rats were randomly assigned to receive either saline (Sal) (negative control) or pentylenetetrazole (PTZ) 40 mg/kg i.p. × 3 times/week × 3 weeks. The PTZ group was further subdivided into two groups, the first received oral l-carnitine (l-Car) (100 mg/kg/day × 4 weeks) (PTZ + l-Car), while the second group received saline (PTZ + Sal). Daily identification and quantification of seizure scores, time to the first seizure and the duration of seizures were performed in each animal. Molecular oxidative markers were examined in the animal brains. l-Car treatment was associated with marked reduction in seizure score (p = 0.0002) that was indicated as early as Day 2 of treatment and continued throughout treatment duration. Furthermore, l-Car significantly prolonged the time to the first seizure (p < 0.0001) and shortened seizure duration (p = 0.028). In addition, l-Car administration for four weeks attenuated PTZ-induced increase in the level of oxidative stress marker malondialdehyde (MDA) (p < 0.0001) and reduced the activity of catalase enzyme (p = 0.0006) and increased antioxidant GSH activity (p < 0.0001). Moreover, l-Car significantly reduced PTZ-induced elevation in protein expression of caspase-3 (p < 0.0001) and β-catenin (p < 0.0001). Overall, our results suggest a potential therapeutic role of l-Car in seizure control and call for testing these preclinical results in a proof of concept pilot clinical study.
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Affiliation(s)
- Abdelaziz M Hussein
- Department of Medical Physiology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt.
| | - Mohamed Adel
- Department of Medical Physiology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt.
| | - Mohamed El-Mesery
- Department of Biochemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
| | - Khaled M Abbas
- Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt.
| | - Amr N Ali
- Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt.
| | - Osama A Abulseoud
- Neuroimaging Research Branch, IRP, National Institute on Drug Abuse, National Institutes of Health, Biomedical Research Center, 251 Bayview Blvd, Baltimore, MD 21224, USA.
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16
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Miyata M, Maruo T, Kaito A, Wang S, Yamamoto H, Fujiwara T, Mizoguchi A, Mandai K, Takai Y. Roles of afadin in the formation of the cellular architecture of the mouse hippocampus and dentate gyrus. Mol Cell Neurosci 2017; 79:34-44. [DOI: 10.1016/j.mcn.2016.12.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 11/15/2016] [Accepted: 12/27/2016] [Indexed: 12/19/2022] Open
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17
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Pirone A, Alexander J, Lau LA, Hampton D, Zayachkivsky A, Yee A, Yee A, Jacob MH, Dulla CG. APC conditional knock-out mouse is a model of infantile spasms with elevated neuronal β-catenin levels, neonatal spasms, and chronic seizures. Neurobiol Dis 2016; 98:149-157. [PMID: 27852007 DOI: 10.1016/j.nbd.2016.11.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 10/24/2016] [Accepted: 11/11/2016] [Indexed: 01/08/2023] Open
Abstract
Infantile spasms (IS) are a catastrophic childhood epilepsy syndrome characterized by flexion-extension spasms during infancy that progress to chronic seizures and cognitive deficits in later life. The molecular causes of IS are poorly defined. Genetic screens of individuals with IS have identified multiple risk genes, several of which are predicted to alter β-catenin pathways. However, evidence linking malfunction of β-catenin pathways and IS is lacking. Here, we show that conditional deletion in mice of the adenomatous polyposis coli gene (APC cKO), the major negative regulator of β-catenin, leads to excessive β-catenin levels and multiple salient features of human IS. Compared with wild-type littermates, neonatal APC cKO mice exhibit flexion-extension motor spasms and abnormal high-amplitude electroencephalographic discharges. Additionally, the frequency of excitatory postsynaptic currents is increased in layer V pyramidal cells, the major output neurons of the cerebral cortex. At adult ages, APC cKOs display spontaneous electroclinical seizures. These data provide the first evidence that malfunctions of APC/β-catenin pathways cause pathophysiological changes consistent with IS. Our findings demonstrate that the APC cKO is a new genetic model of IS, provide novel insights into molecular and functional alterations that can lead to IS, and suggest novel targets for therapeutic intervention.
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Affiliation(s)
- Antonella Pirone
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States
| | - Jonathan Alexander
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States; Neuroscience Program, Tufts Sackler School of Biomedical Sciences, Boston, MA 02111, United States
| | - Lauren A Lau
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States; Neuroscience Program, Tufts Sackler School of Biomedical Sciences, Boston, MA 02111, United States
| | - David Hampton
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States
| | - Andrew Zayachkivsky
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06520, United States
| | - Amy Yee
- Department of Developmental, Molecular, and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, United States
| | - Audrey Yee
- VA Eastern Colorado Health System, Golden, CO 80401, United States
| | - Michele H Jacob
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States.
| | - Chris G Dulla
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States.
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18
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Gammie SC. Current Models and Future Directions for Understanding the Neural Circuitries of Maternal Behaviors in Rodents. ACTA ACUST UNITED AC 2016; 4:119-35. [PMID: 16251728 DOI: 10.1177/1534582305281086] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Maternal behaviors in rodents include a number of subcomponents, such as nursing, nest building, licking and grooming of pups, pup retrieval, and maternal aggression. Because each behavior involves a unique motor pattern, a unique ensemble neural circuitry must underlie each behavior. To what extent there is overlap in terms of brain regions and specific neurons for each circuit is being actively investigated. This review will first examine overlapping and separate components of pup retrieval and maternal aggression circuitries while examining a central role for medial preoptic area (MPA) in both behaviors. With an emphasis on experimental approaches, the review will then highlight recent findings and propose future directions for understanding maternal behavior regulation. Finally, examples for why studying the neural basis of maternal behaviors can bring insights to other areas of neuroscience, such as feeding, addiction, and anxiety and aggression regulation will be provided.
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19
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The Role of Wnt/β-Catenin Signaling Pathway in Disrupted Hippocampal Neurogenesis of Temporal Lobe Epilepsy: A Potential Therapeutic Target? Neurochem Res 2015; 40:1319-32. [PMID: 26012365 DOI: 10.1007/s11064-015-1614-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 05/06/2015] [Accepted: 05/12/2015] [Indexed: 02/05/2023]
Abstract
Temporal lobe epilepsy is one of the most common clinical neurological disorders. One of the major pathological findings in temporal lobe epilepsy is hippocampal sclerosis, characterized by massive neuronal loss and severe gliosis. The epileptogenesis process of temporal lobe epilepsy usually starts with initial precipitating insults, followed by neurodegeneration, abnormal hippocampus circuitry reorganization, and the formation of hypersynchronicity. Experimental and clinical evidence strongly suggests that dysfunctional neurogenesis is involved in the epileptogenesis. Recent data demonstrate that neurogenesis is induced by acute seizures or precipitating insults, whereas the capacity of neuronal recruitment and proliferation substantially decreases in the chronic phase of epilepsy. Participation of the Wnt/β-catenin signaling pathway in neurogenesis reveals its importance in epileptogenesis; its dysfunction contributes to the structural and functional abnormality of temporal lobe epilepsy, while rescuing this pathway exerts neuroprotective effects. Here, we summarize data supporting the involvement of Wnt/β-catenin signaling in the epileptogenesis of temporal lobe epilepsy. We also propose that the Wnt/β-catenin signaling pathway may serve as a promising therapeutic target for temporal lobe epilepsy treatment.
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20
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Kuechler A, Willemsen MH, Albrecht B, Bacino CA, Bartholomew DW, van Bokhoven H, van den Boogaard MJH, Bramswig N, Büttner C, Cremer K, Czeschik JC, Engels H, van Gassen K, Graf E, van Haelst M, He W, Hogue JS, Kempers M, Koolen D, Monroe G, de Munnik S, Pastore M, Reis A, Reuter MS, Tegay DH, Veltman J, Visser G, van Hasselt P, Smeets EEJ, Vissers L, Wieland T, Wissink W, Yntema H, Zink AM, Strom TM, Lüdecke HJ, Kleefstra T, Wieczorek D. De novo mutations in beta-catenin (CTNNB1) appear to be a frequent cause of intellectual disability: expanding the mutational and clinical spectrum. Hum Genet 2014; 134:97-109. [PMID: 25326669 DOI: 10.1007/s00439-014-1498-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 10/03/2014] [Indexed: 10/24/2022]
Abstract
Recently, de novo heterozygous loss-of-function mutations in beta-catenin (CTNNB1) were described for the first time in four individuals with intellectual disability (ID), microcephaly, limited speech and (progressive) spasticity, and functional consequences of CTNNB1 deficiency were characterized in a mouse model. Beta-catenin is a key downstream component of the canonical Wnt signaling pathway. Somatic gain-of-function mutations have already been found in various tumor types, whereas germline loss-of-function mutations in animal models have been shown to influence neuronal development and maturation. We report on 16 additional individuals from 15 families in whom we newly identified de novo loss-of-function CTNNB1 mutations (six nonsense, five frameshift, one missense, two splice mutation, and one whole gene deletion). All patients have ID, motor delay and speech impairment (both mostly severe) and abnormal muscle tone (truncal hypotonia and distal hypertonia/spasticity). The craniofacial phenotype comprised microcephaly (typically -2 to -4 SD) in 12 of 16 and some overlapping facial features in all individuals (broad nasal tip, small alae nasi, long and/or flat philtrum, thin upper lip vermillion). With this detailed phenotypic characterization of 16 additional individuals, we expand and further establish the clinical and mutational spectrum of inactivating CTNNB1 mutations and thereby clinically delineate this new CTNNB1 haploinsufficiency syndrome.
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Affiliation(s)
- Alma Kuechler
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany,
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21
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Tucci V, Kleefstra T, Hardy A, Heise I, Maggi S, Willemsen MH, Hilton H, Esapa C, Simon M, Buenavista MT, McGuffin LJ, Vizor L, Dodero L, Tsaftaris S, Romero R, Nillesen WN, Vissers LELM, Kempers MJ, Vulto-van Silfhout AT, Iqbal Z, Orlando M, Maccione A, Lassi G, Farisello P, Contestabile A, Tinarelli F, Nieus T, Raimondi A, Greco B, Cantatore D, Gasparini L, Berdondini L, Bifone A, Gozzi A, Wells S, Nolan PM. Dominant β-catenin mutations cause intellectual disability with recognizable syndromic features. J Clin Invest 2014; 124:1468-82. [PMID: 24614104 DOI: 10.1172/jci70372] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 01/09/2014] [Indexed: 12/18/2022] Open
Abstract
The recent identification of multiple dominant mutations in the gene encoding β-catenin in both humans and mice has enabled exploration of the molecular and cellular basis of β-catenin function in cognitive impairment. In humans, β-catenin mutations that cause a spectrum of neurodevelopmental disorders have been identified. We identified de novo β-catenin mutations in patients with intellectual disability, carefully characterized their phenotypes, and were able to define a recognizable intellectual disability syndrome. In parallel, characterization of a chemically mutagenized mouse line that displays features similar to those of human patients with β-catenin mutations enabled us to investigate the consequences of β-catenin dysfunction through development and into adulthood. The mouse mutant, designated batface (Bfc), carries a Thr653Lys substitution in the C-terminal armadillo repeat of β-catenin and displayed a reduced affinity for membrane-associated cadherins. In association with this decreased cadherin interaction, we found that the mutation results in decreased intrahemispheric connections, with deficits in dendritic branching, long-term potentiation, and cognitive function. Our study provides in vivo evidence that dominant mutations in β-catenin underlie losses in its adhesion-related functions, which leads to severe consequences, including intellectual disability, childhood hypotonia, progressive spasticity of lower limbs, and abnormal craniofacial features in adults.
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22
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Neural crest-derived mesenchymal cells require Wnt signaling for their development and drive invagination of the telencephalic midline. PLoS One 2014; 9:e86025. [PMID: 24516524 PMCID: PMC3916303 DOI: 10.1371/journal.pone.0086025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 12/08/2013] [Indexed: 11/19/2022] Open
Abstract
Embryonic neural crest cells contribute to the development of the craniofacial mesenchyme, forebrain meninges and perivascular cells. In this study, we investigated the function of ß-catenin signaling in neural crest cells abutting the dorsal forebrain during development. In the absence of ß-catenin signaling, neural crest cells failed to expand in the interhemispheric region and produced ectopic smooth muscle cells instead of generating dermal and calvarial mesenchyme. In contrast, constitutive expression of stabilized ß-catenin in neural crest cells increased the number of mesenchymal lineage precursors suggesting that ß-catenin signaling is necessary for the expansion of neural crest-derived mesenchymal cells. Interestingly, the loss of neural crest-derived mesenchymal stem cells (MSCs) leads to failure of telencephalic midline invagination and causes ventricular system defects. This study shows that ß-catenin signaling is required for the switch of neural crest cells to MSCs and mediates the expansion of MSCs to drive the formation of mesenchymal structures of the head. Furthermore, loss of these structures causes striking defects in forebrain morphogenesis.
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23
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Wang HT, Zeng L, Zhang X, Li K, Zu Y, Liu JW, Liu YJ, Zhu ZC, Xiong ZQ, Zheng J, Hu ZL. Inactivation of β-catenin results in the reduction of postnatal body weight gain. Brain Res Bull 2014; 100:55-60. [DOI: 10.1016/j.brainresbull.2013.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 11/01/2013] [Accepted: 11/11/2013] [Indexed: 11/29/2022]
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24
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Grafodatskaya D, Chung BHY, Butcher DT, Turinsky AL, Goodman SJ, Choufani S, Chen YA, Lou Y, Zhao C, Rajendram R, Abidi FE, Skinner C, Stavropoulos J, Bondy CA, Hamilton J, Wodak S, Scherer SW, Schwartz CE, Weksberg R. Multilocus loss of DNA methylation in individuals with mutations in the histone H3 lysine 4 demethylase KDM5C. BMC Med Genomics 2013; 6:1. [PMID: 23356856 PMCID: PMC3573947 DOI: 10.1186/1755-8794-6-1] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/14/2013] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND A number of neurodevelopmental syndromes are caused by mutations in genes encoding proteins that normally function in epigenetic regulation. Identification of epigenetic alterations occurring in these disorders could shed light on molecular pathways relevant to neurodevelopment. RESULTS Using a genome-wide approach, we identified genes with significant loss of DNA methylation in blood of males with intellectual disability and mutations in the X-linked KDM5C gene, encoding a histone H3 lysine 4 demethylase, in comparison to age/sex matched controls. Loss of DNA methylation in such individuals is consistent with known interactions between DNA methylation and H3 lysine 4 methylation. Further, loss of DNA methylation at the promoters of the three top candidate genes FBXL5, SCMH1, CACYBP was not observed in more than 900 population controls. We also found that DNA methylation at these three genes in blood correlated with dosage of KDM5C and its Y-linked homologue KDM5D. In addition, parallel sex-specific DNA methylation profiles in brain samples from control males and females were observed at FBXL5 and CACYBP. CONCLUSIONS We have, for the first time, identified epigenetic alterations in patient samples carrying a mutation in a gene involved in the regulation of histone modifications. These data support the concept that DNA methylation and H3 lysine 4 methylation are functionally interdependent. The data provide new insights into the molecular pathogenesis of intellectual disability. Further, our data suggest that some DNA methylation marks identified in blood can serve as biomarkers of epigenetic status in the brain.
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Affiliation(s)
- Daria Grafodatskaya
- Genetics and Genome Biology Program, Hospital for Sick Children, Toronto, ON, Canada
| | - Barian HY Chung
- Division of Clinical and Metabolic Genetics, Hospital for Sick Children, Toronto, ON, Canada
- Centre of Reproduction, Growth & Development, Department of Pediatrics & Adolescent Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - Darci T Butcher
- Genetics and Genome Biology Program, Hospital for Sick Children, Toronto, ON, Canada
| | - Andrei L Turinsky
- Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, ON, Canada
| | - Sarah J Goodman
- Centre of Reproduction, Growth & Development, Department of Pediatrics & Adolescent Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - Sana Choufani
- Centre of Reproduction, Growth & Development, Department of Pediatrics & Adolescent Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - Yi-An Chen
- Genetics and Genome Biology Program, Hospital for Sick Children, Toronto, ON, Canada
| | - Youliang Lou
- Genetics and Genome Biology Program, Hospital for Sick Children, Toronto, ON, Canada
| | - Chunhua Zhao
- Genetics and Genome Biology Program, Hospital for Sick Children, Toronto, ON, Canada
| | - Rageen Rajendram
- Genetics and Genome Biology Program, Hospital for Sick Children, Toronto, ON, Canada
| | - Fatima E Abidi
- J.C. Self Research Institute, Greenwood Genetic Center, Greenwood, SC, USA
| | - Cindy Skinner
- J.C. Self Research Institute, Greenwood Genetic Center, Greenwood, SC, USA
| | - James Stavropoulos
- Department of Pediatric Laboratory Medicine, Hospital for Sick Children, Toronto, ON, Canada
| | - Carolyn A Bondy
- Developmental Endocrinology Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Jill Hamilton
- Division of Endocrinology, Department of Pediatrics, Hospital for Sick Children, Toronto, ON, Canada
- Department of Pediatrics, University of Toronto, Toronto, ON, Canada
| | - Shoshana Wodak
- Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular and Medical Genetics, University of Toronto, Toronto, ON, Canada
| | - Stephen W Scherer
- Department of Molecular and Medical Genetics, University of Toronto, Toronto, ON, Canada
- The Centre for Applied Genomics, Hospital for Sick Children, Toronto, ON, Canada
| | - Charles E Schwartz
- J.C. Self Research Institute, Greenwood Genetic Center, Greenwood, SC, USA
| | - Rosanna Weksberg
- Division of Clinical and Metabolic Genetics, Hospital for Sick Children, Toronto, ON, Canada
- Department of Pediatrics, University of Toronto, Toronto, ON, Canada
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25
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Tapia M, Del Puerto A, Puime A, Sánchez-Ponce D, Fronzaroli-Molinieres L, Pallas-Bazarra N, Carlier E, Giraud P, Debanne D, Wandosell F, Garrido JJ. GSK3 and β-catenin determines functional expression of sodium channels at the axon initial segment. Cell Mol Life Sci 2013; 70:105-20. [PMID: 22763697 PMCID: PMC11113494 DOI: 10.1007/s00018-012-1059-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 05/21/2012] [Accepted: 06/12/2012] [Indexed: 10/28/2022]
Abstract
Neuronal action potentials are generated through voltage-gated sodium channels, which are tethered by ankyrinG at the membrane of the axon initial segment (AIS). Despite the importance of the AIS in the control of neuronal excitability, the cellular and molecular mechanisms regulating sodium channel expression at the AIS remain elusive. Our results show that GSK3α/β and β-catenin phosphorylated by GSK3 (S33/37/T41) are localized at the AIS and are new components of this essential neuronal domain. Pharmacological inhibition of GSK3 or β-catenin knockdown with shRNAs decreased the levels of phosphorylated-β-catenin, ankyrinG, and voltage-gated sodium channels at the AIS, both "in vitro" and "in vivo", therefore diminishing neuronal excitability as evaluated via sodium current amplitude and action potential number. Thus, our results suggest a mechanism for the modulation of neuronal excitability through the control of sodium channel density by GSK3 and β-catenin at the AIS.
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Affiliation(s)
- Mónica Tapia
- Department of Cellular, Molecular and Developmental Neurobiology, Instituto Cajal, CSIC, Avenida Doctor Arce, Madrid, 28002 Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Ana Del Puerto
- Department of Cellular, Molecular and Developmental Neurobiology, Instituto Cajal, CSIC, Avenida Doctor Arce, Madrid, 28002 Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Alberto Puime
- Departamento de Anatomía Patológica, Capio Fundación Jiménez Díaz, Madrid, 28040 Spain
| | - Diana Sánchez-Ponce
- Department of Cellular, Molecular and Developmental Neurobiology, Instituto Cajal, CSIC, Avenida Doctor Arce, Madrid, 28002 Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | | | - Noemí Pallas-Bazarra
- Department of Cellular, Molecular and Developmental Neurobiology, Instituto Cajal, CSIC, Avenida Doctor Arce, Madrid, 28002 Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Edmond Carlier
- INSERM U1072, Marseille, 13344 France
- Aix-Marseille University, U1072, Marseille, 13344 France
| | - Pierre Giraud
- INSERM U1072, Marseille, 13344 France
- Aix-Marseille University, U1072, Marseille, 13344 France
| | - Dominique Debanne
- INSERM U1072, Marseille, 13344 France
- Aix-Marseille University, U1072, Marseille, 13344 France
| | - Francisco Wandosell
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Juan José Garrido
- Department of Cellular, Molecular and Developmental Neurobiology, Instituto Cajal, CSIC, Avenida Doctor Arce, Madrid, 28002 Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
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Yokoi F, Dang MT, Li Y. Improved motor performance in Dyt1 ΔGAG heterozygous knock-in mice by cerebellar Purkinje-cell specific Dyt1 conditional knocking-out. Behav Brain Res 2012; 230:389-98. [PMID: 22391119 PMCID: PMC3322286 DOI: 10.1016/j.bbr.2012.02.029] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 02/11/2012] [Accepted: 02/17/2012] [Indexed: 01/23/2023]
Abstract
Early-onset generalized torsion dystonia (dystonia 1) is an inherited movement disorder caused by mutations in DYT1 (TOR1A), which codes for torsinA. Most patients have a 3-base pair deletion (ΔGAG) in one allele of DYT1, corresponding to a loss of a glutamic acid residue (ΔE) in the C-terminal region of the protein. Functional alterations in basal ganglia circuits and the cerebellum have been reported in dystonia. Pharmacological manipulations or mutations in genes that result in functional alterations of the cerebellum have been reported to have dystonic symptoms and have been used as phenotypic rodent models. Additionally, structural lesions in the abnormal cerebellar circuits, such as cerebellectomy, have therapeutic effects in these models. A previous study has shown that the Dyt1 ΔGAG heterozygous knock-in (KI) mice exhibit motor deficits in the beam-walking test. Both Dyt1 ΔGAG heterozygous knock-in (KI) and Dyt1 Purkinje cell-specific knockout (Dyt1 pKO) mice exhibit dendritic alterations of cerebellar Purkinje cells. Here, Dyt1 pKO mice exhibited significantly less slip numbers in the beam-walking test, suggesting better motor performance than control littermates, and normal gait. Furthermore, Dyt1 ΔGAG KI/Dyt1 pKO double mutant mice exhibited significantly lower numbers of slips than Dyt1 ΔGAG heterozygous KI mice, suggesting Purkinje-cell specific knockout of Dyt1 wild-type (WT) allele in Dyt1 ΔGAG heterozygous KI mice rescued the motor deficits. The results suggest that molecular lesions of torsinA in Purkinje cells by gene therapy or intervening in the signaling pathway downstream of the cerebellar Purkinje cells may rescue motor symptoms in dystonia 1.
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Affiliation(s)
- Fumiaki Yokoi
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, 32610-0236, USA
| | - Mai Tu Dang
- Department of Neurology, Hospital of University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Yuqing Li
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, 32610-0236, USA
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Yokoi F, Dang MT, Yang G, Li J, Doroodchi A, Zhou T, Li Y. Abnormal nuclear envelope in the cerebellar Purkinje cells and impaired motor learning in DYT11 myoclonus-dystonia mouse models. Behav Brain Res 2012; 227:12-20. [PMID: 22040906 PMCID: PMC3242862 DOI: 10.1016/j.bbr.2011.10.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 10/10/2011] [Accepted: 10/16/2011] [Indexed: 11/22/2022]
Abstract
Myoclonus-dystonia (M-D) is a movement disorder characterized by myoclonic jerks with dystonia. DYT11 M-D is caused by mutations in SGCE which codes for ɛ-sarcoglycan. SGCE is maternally imprinted and paternally expressed. Abnormal nuclear envelope has been reported in mouse models of DYT1 generalized torsion dystonia. However, it is not known whether similar alterations occur in DYT11 M-D. We developed a mouse model of DYT11 M-D using paternally inherited Sgce heterozygous knockout (Sgce KO) mice and reported that they had myoclonus and motor coordination and learning deficits in the beam-walking test. However, the specific brain regions that contribute to these phenotypes have not been identified. Since ɛ-sarcoglycan is highly expressed in the cerebellar Purkinje cells, here we examined the nuclear envelope in these cells using a transmission electron microscope and found that they are abnormal in Sgce KO mice. Our results put DYT11 M-D in a growing family of nuclear envelopathies. To analyze the effect of loss of ɛ-sarcoglycan function in the cerebellar Purkinje cells, we produced paternally inherited cerebellar Purkinje cell-specific Sgce conditional knockout (Sgce pKO) mice. Sgce pKO mice showed motor learning deficits, while they did not show abnormal nuclear envelope in the cerebellar Purkinje cells, robust motor deficits, or myoclonus. The results suggest that ɛ-sarcoglycan in the cerebellar Purkinje cells contributes to the motor learning, while loss of ɛ-sarcoglycan in other brain regions may contribute to nuclear envelope abnormality, myoclonus and motor coordination deficits.
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Affiliation(s)
- Fumiaki Yokoi
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Mai T. Dang
- Department of Neurology, Hospital of University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Guang Yang
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - JinDong Li
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Atbin Doroodchi
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Tong Zhou
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yuqing Li
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
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Boggetti B, Niessen CM. Adherens junctions in mammalian development, homeostasis and disease: lessons from mice. Subcell Biochem 2012; 60:321-55. [PMID: 22674078 DOI: 10.1007/978-94-007-4186-7_14] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Mice have proven to be a particularly powerful model to study molecular mechanisms of development and disease. The reason for this is the close evolutionary relationship between rodents and humans, similarities in physiological mechanisms in mice and human, and the large number of techniques available to study gene functions in mice. A large number of mice mutations, either germ line, conditional or inducible, have been generated in the past years for adherens junctions components, and the number is still increasing. In this review we will discuss mice models that have contributed to understanding the developmental and physiological role of adherens junctions and their components in mammals and have revealed novel mechanistic aspects of how adherens junctions regulate morphogenesis and tissue homeostasis.
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Affiliation(s)
- Barbara Boggetti
- Department of Dermatology, Center for Molecular Medicine, University of Cologne, Room 4A.05, Robert Kochstrasse 21, 50931, Cologne, Germany
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Yokoi F, Dang MT, Zhou T, Li Y. Abnormal nuclear envelopes in the striatum and motor deficits in DYT11 myoclonus-dystonia mouse models. Hum Mol Genet 2011; 21:916-25. [PMID: 22080833 DOI: 10.1093/hmg/ddr528] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
DYT11 myoclonus-dystonia (M-D) is a movement disorder characterized by myoclonic jerks with dystonic symptoms and caused by mutations in paternally expressed SGCE, which codes for ε-sarcoglycan. Paternally inherited Sgce heterozygous knock-out (KO) mice exhibit motor deficits and spontaneous myoclonus. Abnormal nuclear envelopes have been reported in cellular and mouse models of early-onset DYT1 generalized torsion dystonia; however, the relationship between the abnormal nuclear envelopes and motor symptoms are not clear. Furthermore, it is not known whether abnormal nuclear envelope exists in non-DYT1 dystonia. In the present study, abnormal nuclear envelopes in the striatal medium spiny neurons (MSNs) were found in Sgce KO mice. To analyze whether the loss of ε-sarcoglycan in the striatum alone causes abnormal nuclear envelopes, motor deficits or myoclonus, we produced paternally inherited striatum-specific Sgce conditional KO (Sgce sKO) mice and analyzed their phenotypes. Sgce sKO mice exhibited motor deficits in both beam-walking and accelerated rotarod tests, while they did not exhibit abnormal nuclear envelopes, alteration in locomotion, or myoclonus. The results suggest that the loss of ε-sarcoglycan in the striatum contributes to motor deficits, while it alone does not produce abnormal nuclear envelopes or myoclonus. Development of therapies targeting the striatum to compensate for the loss of ε-sarcoglycan function may rescue the motor deficits in DYT11 M-D patients.
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Affiliation(s)
- Fumiaki Yokoi
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610-0236, USA
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Motor deficits and decreased striatal dopamine receptor 2 binding activity in the striatum-specific Dyt1 conditional knockout mice. PLoS One 2011; 6:e24539. [PMID: 21931745 PMCID: PMC3171455 DOI: 10.1371/journal.pone.0024539] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 08/12/2011] [Indexed: 11/23/2022] Open
Abstract
DYT1 early-onset generalized dystonia is a hyperkinetic movement disorder caused by mutations in DYT1 (TOR1A), which codes for torsinA. Recently, significant progress has been made in studying pathophysiology of DYT1 dystonia using targeted mouse models. Dyt1 ΔGAG heterozygous knock-in (KI) and Dyt1 knock-down (KD) mice exhibit motor deficits and alterations of striatal dopamine metabolisms, while Dyt1 knockout (KO) and Dyt1 ΔGAG homozygous KI mice show abnormal nuclear envelopes and neonatal lethality. However, it has not been clear whether motor deficits and striatal abnormality are caused by Dyt1 mutation in the striatum itself or the end results of abnormal signals from other brain regions. To identify the brain region that contributes to these phenotypes, we made a striatum-specific Dyt1 conditional knockout (Dyt1 sKO) mouse. Dyt1 sKO mice exhibited motor deficits and reduced striatal dopamine receptor 2 (D2R) binding activity, whereas they did not exhibit significant alteration of striatal monoamine contents. Furthermore, we also found normal nuclear envelope structure in striatal medium spiny neurons (MSNs) of an adult Dyt1 sKO mouse and cerebral cortical neurons in cerebral cortex-specific Dyt1 conditional knockout (Dyt1 cKO) mice. The results suggest that the loss of striatal torsinA alone is sufficient to produce motor deficits, and that this effect may be mediated, at least in part, through changes in D2R function in the basal ganglia circuit.
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Is intractable epilepsy a tauopathy? Med Hypotheses 2011; 76:897-900. [DOI: 10.1016/j.mehy.2011.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 01/14/2011] [Accepted: 03/03/2011] [Indexed: 12/20/2022]
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Zhang L, Yokoi F, Jin YH, DeAndrade MP, Hashimoto K, Standaert DG, Li Y. Altered dendritic morphology of Purkinje cells in Dyt1 ΔGAG knock-in and purkinje cell-specific Dyt1 conditional knockout mice. PLoS One 2011; 6:e18357. [PMID: 21479250 PMCID: PMC3066238 DOI: 10.1371/journal.pone.0018357] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Accepted: 02/28/2011] [Indexed: 11/18/2022] Open
Abstract
Background DYT1 early-onset generalized dystonia is a neurological movement disorder characterized by involuntary muscle contractions. It is caused by a trinucleotide deletion of a GAG (ΔGAG) in the DYT1 (TOR1A) gene encoding torsinA; the mouse homolog of this gene is Dyt1 (Tor1a). Although structural and functional alterations in the cerebellum have been reported in DYT1 dystonia, neuronal morphology has not been examined in vivo. Methodology/Principal Findings In this study, we examined the morphology of the cerebellum in Dyt1 ΔGAG knock-in (KI) mice. Golgi staining of the cerebellum revealed a reduction in the length of primary dendrites and a decrease in the number of spines on the distal dendrites of Purkinje cells. To determine if this phenomenon was cell autonomous and mediated by a loss of torsinA function in Purkinje cells, we created a knockout of the Dyt1 gene only in Purkinje cells of mice. We found the Purkinje-cell specific Dyt1 conditional knockout (Dyt1 pKO) mice have similar alterations in Purkinje cell morphology, with shortened primary dendrites and decreased spines on the distal dendrites. Conclusion/Significance These results suggest that the torsinA is important for the proper development of the cerebellum and a loss of this function in the Purkinje cells results in an alteration in dendritic structure.
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Affiliation(s)
- Lin Zhang
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Fumiaki Yokoi
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Yuan-Hu Jin
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Mark P. DeAndrade
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Kenji Hashimoto
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan
| | - David G. Standaert
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Yuqing Li
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- * E-mail:
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Chen CM, Wang HY, You LR, Shang RL, Liu FC. Expression analysis of an evolutionarily conserved metallophosphodiesterase gene, Mpped1, in the normal and beta-catenin-deficient malformed dorsal telencephalon. Dev Dyn 2010; 239:1797-806. [PMID: 20503375 DOI: 10.1002/dvdy.22293] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
We report the expression of the mouse Mpped1 in the telencephalon through embryonic stages to adulthood. Using Northern blotting analysis and RNA in situ hybridization (ISH), our data show that Mpped1 is specifically expressed in the brain and is enriched in the cortical plate of the developing telencephalon. Postnatally, the expression of Mpped1 is reduced in the cerebral cortex relative to its levels in the embryonic dorsal telencephalon. Also, Mpped1 expression is sustained in the hippocampal CA1 region. Examination of the expression of Mpped1 and other cortical layer markers by ISH in a malformed beta-catenin null dorsal telencephalon show that the Mpped1-, Cux2-, and Rorbeta-expressing superficial cortical layers are reduced and form patchy patterns, and the Tbr-1-expressing deep-layer neurons are incorrectly located on superficial layers, indicative of a migration defect of cortical neurons in the absence of beta-catenin.
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Affiliation(s)
- Chun-Ming Chen
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.
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Cournoyer P, Desrosiers RR. Valproic acid enhances protein L-isoaspartyl methyltransferase expression by stimulating extracellular signal-regulated kinase signaling pathway. Neuropharmacology 2009; 56:839-48. [PMID: 19371592 DOI: 10.1016/j.neuropharm.2009.01.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Revised: 01/06/2009] [Accepted: 01/09/2009] [Indexed: 11/29/2022]
Abstract
Proteins are susceptible to various non-enzymatic post-translational modifications occurring during aging and in certain pathological states. The protein L-isoaspartyl methyltransferase (PIMT) is an enzyme that recognizes and repairs the abnormal L-isoaspartyl residues in proteins. Recently, we reported that PIMT expression was stimulated by the anti-epileptic drug valproic acid and that this was mediated through the glycogen synthase kinase-3 (GSK-3)/beta-catenin pathway. In this study, to gain further insights into which of the signaling pathways activated by valproic acid regulate PIMT abundance, astrocytoma U-87 MG and neuroblastoma SH-SY5Y cells were treated with this drug to investigate the possible involvement of the extracellular-regulated kinase (ERK) pathway in PIMT induction. Valproic acid increased ERK1/2 phosphorylation on Thr202/Tyr204 and Thr185/Tyr187, respectively. Pharmacological inhibitors against the kinases Src, c-Raf, MEK1/2 and ERK1/2 abolished the ERK1/2 phosphorylation stimulated by valproic acid, thus preventing PIMT induction by the drug. Furthermore, MEK1/2 inhibition with U0126 blocked the higher phosphorylation of RSK-1 on Thr359/Ser363 and of GSK-3beta on Ser9 as well as the increased expression of RSK-1, beta-catenin and PIMT upon treatment with valproic acid. RSK-1 knockdown by interfering RNA abrogated the increased expression of RSK-1, beta-catenin and PIMT as well as the induced phosphorylation of RSK-1 and GSK-3beta due to valproic acid. Thus, our findings demonstrated that PIMT up-regulation by valproic acid required the activation of the ERK signaling pathway including RSK-1 the latter being responsible for inactivating GSK-3 and subsequently leading to beta-catenin stabilization.
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Affiliation(s)
- Philippe Cournoyer
- Université du Québec à Montréal, C.P. 8888, Succursale Centre-Ville, Montréal, Québec, Canada H3C 3P8
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35
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Grigoryan T, Wend P, Klaus A, Birchmeier W. Deciphering the function of canonical Wnt signals in development and disease: conditional loss- and gain-of-function mutations of beta-catenin in mice. Genes Dev 2008; 22:2308-41. [PMID: 18765787 PMCID: PMC2749675 DOI: 10.1101/gad.1686208] [Citation(s) in RCA: 452] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Wnt signaling is one of a handful of powerful signaling pathways that play crucial roles in the animal life by controlling the genetic programs of embryonic development and adult homeostasis. When disrupted, these signaling pathways cause developmental defects, or diseases, among them cancer. The gateway of the canonical Wnt pathway, which contains >100 genes, is an essential molecule called beta-catenin (Armadillo in Drosophila). Conditional loss- and gain-of-function mutations of beta-catenin in mice provided powerful tools for the functional analysis of canonical Wnt signaling in many tissues and organs. Such studies revealed roles of Wnt signaling that were previously not accessible to genetic analysis due to the early embryonic lethality of conventional beta-catenin knockout mice, as well as the redundancy of Wnt ligands, receptors, and transcription factors. Analysis of conditional beta-catenin loss- and gain-of-function mutant mice demonstrated that canonical Wnt signals control progenitor cell expansion and lineage decisions both in the early embryo and in many organs. Canonical Wnt signaling also plays important roles in the maintenance of various embryonic or adult stem cells, and as recent findings demonstrated, in cancer stem cell types. This has opened new opportunities to model numerous human diseases, which have been associated with deregulated Wnt signaling. Our review summarizes what has been learned from genetic studies of the Wnt pathway by the analysis of conditional beta-catenin loss- and gain-of-function mice.
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Affiliation(s)
- Tamara Grigoryan
- Max-Delbück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Peter Wend
- Max-Delbück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Alexandra Klaus
- Max-Delbück Center for Molecular Medicine, 13125 Berlin, Germany
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36
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Up-regulation of protein L-isoaspartyl methyltransferase expression by lithium is mediated by glycogen synthase kinase-3 inactivation and beta-catenin stabilization. Neuropharmacology 2008; 55:669-76. [PMID: 18582478 DOI: 10.1016/j.neuropharm.2008.05.033] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Revised: 05/27/2008] [Accepted: 05/30/2008] [Indexed: 12/31/2022]
Abstract
During cell aging, proteins accumulate damages, which affect their structure and activity. The protein l-isoaspartyl methyltransferase (PIMT) is involved in the repair of proteins containing abnormal L-isoaspartyl residues. Although its mechanism of action is well defined, little is known about the pathways involved in the regulation of PIMT expression. In this study, we demonstrated that glycogen synthase kinase-3 (GSK-3) and beta-catenin are involved in the regulation of PIMT expression. Treatment of astrocytoma cells (U-87) with direct pharmacological GSK-3 inhibitors such as lithium, SB-216763 and SB-415286 stimulated PIMT expression ( approximately twofold). As expected, GSK-3 inhibition led to an increase of phosphorylated GSK-3beta (Ser9) and to beta-catenin accumulation. PIMT induction by lithium was dependent on increased protein synthesis. In addition, RT-PCR analysis showed higher level of PIMT mRNA following GSK-3 inhibition, which was abolished by the transcriptional inhibitor actinomycin D. These results demonstrated regulation of PIMT expression by lithium at both the transcriptional and the translational levels. Additionally, inhibition by siRNA of GSK-3 and beta-catenin modulated the expression of the PIMT in accordance with GSK-3 pharmacological inhibition. Valproic acid, an antiepileptic drug with mood-stabilizing properties, up-regulated phospho-GSK-3beta (Ser9), beta-catenin and PIMT levels similarly to lithium. This study reports that PIMT expression is up-regulated by GSK-3 inhibition and beta-catenin stabilization upon treatments with lithium and valproic acid. These findings suggest a possible therapeutic role for PIMT in certain brain diseases including epilepsy.
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Vashlishan AB, Madison JM, Dybbs M, Bai J, Sieburth D, Ch'ng Q, Tavazoie M, Kaplan JM. An RNAi Screen Identifies Genes that Regulate GABA Synapses. Neuron 2008; 58:346-61. [DOI: 10.1016/j.neuron.2008.02.019] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Revised: 02/12/2008] [Accepted: 02/19/2008] [Indexed: 01/29/2023]
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Gavériaux-Ruff C, Kieffer BL. Conditional gene targeting in the mouse nervous system: Insights into brain function and diseases. Pharmacol Ther 2007; 113:619-34. [PMID: 17289150 DOI: 10.1016/j.pharmthera.2006.12.003] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2006] [Revised: 12/08/2006] [Accepted: 12/08/2006] [Indexed: 11/24/2022]
Abstract
Conditional gene knockout represents an extremely powerful approach to study the function of single genes in the nervous system. The Cre-LoxP system is the most advanced technology for spatial and temporal control of genetic inactivation, and there is rapid progress using this methodology in neuroscience research. In this approach, mice with LoxP sites flanking the gene of interest (floxed mice) are bred with transgenic mice expressing Cre recombinase under the control of a selected promoter (Cre mice). This promoter is critical in that it determines the time and site of Cre expression. Cre enzyme, in turn, recombines the floxed gene and produces gene knockout. Here we review Cre mouse lines that have been developed to target either the entire brain, selected brain areas, or specific neuronal populations. We then summarize phenotypic consequences of conditional gene targeting in the brain for more than 40 genes, as reported to date. For many broadly expressed genes, brain-restricted knockout has overcome lethality of conventional knockout (KO) and has highlighted a specific role of the encoded protein in some aspect of brain function. In the case of neural genes, data from null mutants in specific brain sites or neurons has refined our understanding of the role of individual molecules that regulate complex behaviors or synaptic plasticity within neural circuits. Among the many developing functional genomic approaches, conditional gene targeting in the mouse has become an excellent tool to elucidate the function of the approximately 5000 known or unknown genes that operate in the nervous system.
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Affiliation(s)
- Claire Gavériaux-Ruff
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, UMR7104, Illkirch, France.
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Wahlsten D, Bishop KM, Ozaki HS. Recombinant inbreeding in mice reveals thresholds in embryonic corpus callosum development. GENES BRAIN AND BEHAVIOR 2006; 5:170-88. [PMID: 16507008 DOI: 10.1111/j.1601-183x.2005.00153.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The inbred strains BALB/cWah1 and 129P1/ReJ both show incomplete penetrance for absent corpus callosum (CC); about 14% of adult mice have no CC at all. Their F(1) hybrid offspring are normal, which proves that the strains differ at two or more loci pertinent to absent CC. Twenty-three recombinant inbred lines were bred from the F(2) cross of BALB/c and 129, and several of these expressed a novel and severe phenotype after only three or four generations of inbreeding - total absence of the CC and severe reduction of the hippocampal commissure (HC) in every adult animal. As inbreeding progressed, intermediate sizes of the CC and the HC remained quite rare. This striking phenotypic distribution in adults arose from developmental thresholds in the embryo. CC axons normally cross to the opposite hemisphere via a tissue bridge in the septal region at midline, where the HC forms before CC axons arrive. The primary defect in callosal agenesis in the BALB/c and 129 strains is severe retardation of fusion of the hemispheres in the septal region, and failure to form a CC is secondary to this defect. The putative CC axons arrive at midline at the correct time and place in all groups, but in certain genotypes, the bridge is not yet present. The relative timing of axon growth and delay of the septal bridge create a narrow critical period for forming a normal brain.
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Affiliation(s)
- D Wahlsten
- Department of Psychology, University of Alberta, Edmonton, Canada.
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Francis F, Meyer G, Fallet-Bianco C, Moreno S, Kappeler C, Socorro AC, Tuy FPD, Beldjord C, Chelly J. Human disorders of cortical development: from past to present. Eur J Neurosci 2006; 23:877-93. [PMID: 16519653 DOI: 10.1111/j.1460-9568.2006.04649.x] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Epilepsy and mental retardation, originally of unknown cause, are now known to result from many defects including cortical malformations, neuronal circuitry disorders and perturbations of neuronal communication and synapse function. Genetic approaches in combination with MRI and related imaging techniques continually allow a re-evaluation and better classification of these disorders. Here we review our current understanding of some of the primary defects involved, with insight from recent molecular biology advances, the study of mouse models and the results of neuropathology analyses. Through these studies the molecular determinants involved in the control of neuron number, neuronal migration, generation of cortical laminations and convolutions, integrity of the basement membrane at the pial surface, and the establishment of neuronal circuitry are being elucidated. We have attempted to integrate these results with the available data concerning, in particular, human brain development, and to emphasize the limitations in some cases of extrapolating from rodent models. Taking such species differences into account is clearly critical for understanding the pathophysiological mechanisms associated with these disorders.
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Affiliation(s)
- Fiona Francis
- Institut Cochin, Département de Génétique et Développement, Paris, F-75014 France.
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Dang MT, Yokoi F, McNaught KSP, Jengelley TA, Jackson T, Li J, Li Y. Generation and characterization of Dyt1 DeltaGAG knock-in mouse as a model for early-onset dystonia. Exp Neurol 2005; 196:452-63. [PMID: 16242683 DOI: 10.1016/j.expneurol.2005.08.025] [Citation(s) in RCA: 167] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Revised: 08/29/2005] [Accepted: 08/30/2005] [Indexed: 10/25/2022]
Abstract
A trinucleotide deletion of GAG in the DYT1 gene that encodes torsinA protein is implicated in the neurological movement disorder of Oppenheim's early-onset dystonia. The mutation removes a glutamic acid in the carboxy region of torsinA, a member of the Clp protease/heat shock protein family. The function of torsinA and the role of the mutation in causing dystonia are largely unknown. To gain insight into these unknowns, we made a gene-targeted mouse model of Dyt1 DeltaGAG to mimic the mutation found in DYT1 dystonic patients. The mutated heterozygous mice had deficient performance on the beam-walking test, a measure of fine motor coordination and balance. In addition, they exhibited hyperactivity in the open-field test. Mutant mice also showed a gait abnormality of increased overlap. Mice at 3 months of age did not display deficits in beam-walking and gait, while 6-month mutant mice did, indicating an age factor in phenotypic expression as well. While striatal dopamine and 4-dihydroxyphenylacetic acid (DOPAC) levels in Dyt1 DeltaGAG mice were similar to that of wild-type mice, a 27% decrease in 4-hydroxy, 3-methoxyphenacetic acid (homovanillic acid) was detected in mutant mice. Dyt1 DeltaGAG tissues also have ubiquitin- and torsinA-containing aggregates in neurons of the pontine nuclei. A sex difference was noticed in the mutant mice with female mutant mice exhibiting fewer alterations in behavioral, neurochemical, and cellular changes. Our results show that knocking in a Dyt1 DeltaGAG allele in mouse alters their motor behavior and recapitulates the production of protein aggregates that are seen in dystonic patients. Our data further support alterations in the dopaminergic system as a part of dystonia's neuropathology.
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Affiliation(s)
- Mai T Dang
- Department of Molecular and Integrative Physiology, NeuroTech Group, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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Novikova SI, He F, Bai J, Lidow MS. Neuropathology of the cerebral cortex observed in a range of animal models of prenatal cocaine exposure may reflect alterations in genes involved in the Wnt and cadherin systems. Synapse 2005; 56:105-16. [PMID: 15729737 DOI: 10.1002/syn.20134] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Several recent reports show that the cerebral cortex in humans and animals with altered expressions of Wnt/cadherin network-associate molecules display cytoarchitectural abnormalities reminiscent of cortical dysplasias seen in some (mouse-, rat-, and monkey-based) animal models of prenatal cocaine exposure. Therefore, we employed oligo microarrays followed by real-time RT-PCR to compare expressions of genes involved in Wnt and cadherin systems in the cerebral wall of 18-day-old (E18) fetuses from cocaine-treated (20 mg/kg cocaine, s.c., b.i.d., E8-18) and drug-naive (saline, s.c.) mice. The pregnant mice chronically treated with cocaine in the above-described manner represent one of the animal models producing offspring with widespread cortical dysplasias. Out of more than 150 relevant genes in the arrays, 32 were upregulated and 9 were downregulated in cocaine-exposed fetuses. The majority of these genes (30 out of 41) were similarly affected in the frontal and occipital regions of the cerebral wall. We also used Western immunoblotting to examine the ability of cocaine to regulate the protein levels of beta-catenin, the key functional component of both Wnt and cadherin systems. While the total cell levels of beta-catenin were increased throughout the cerebral wall of cocaine-exposed fetuses, its nuclear (gene-transcription driving) levels remained unaltered. This suggests a transcription-unrelated role for cocaine-induced upregulation of this protein. Overall, our findings point to an intriguing possibility that that cerebral cortical dysplasias observed in several animal models of prenatal cocaine exposure may be at least in part related to alterations in the Wnt/cadherin molecular network.
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Affiliation(s)
- Svetlana I Novikova
- Department of Biomedical Sciences, and Program of Neuroscience, University of Maryland, Baltimore, Maryland 21201, USA
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