51
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Fuchs C, Gennaccaro L, Ren E, Galvani G, Trazzi S, Medici G, Loi M, Conway E, Devinsky O, Rimondini R, Ciani E. Pharmacotherapy with sertraline rescues brain development and behavior in a mouse model of CDKL5 deficiency disorder. Neuropharmacology 2019; 167:107746. [PMID: 31469994 DOI: 10.1016/j.neuropharm.2019.107746] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/27/2019] [Accepted: 08/21/2019] [Indexed: 12/15/2022]
Abstract
Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene cause a severe neurodevelopmental disorder, CDKL5 deficiency disorder (CDD). CDKL5 is fundamental for correct brain development and function, but the molecular mechanisms underlying aberrant neurologic dysfunction in CDD are incompletely understood. Here we show a dysregulation of hippocampal and cortical serotonergic (5-HT) receptor expression in heterozygous Cdkl5 knockout (KO) female mice, suggesting that impaired 5-HT neurotransmission contributes to CDD. We demonstrate that targeting impaired 5-HT signaling via the selective serotonin reuptake inhibitor (SSRI) sertraline rescues CDD-related neurodevelopmental and behavioral defects in heterozygous Cdkl5 KO female mice. In particular, chronic treatment with sertraline normalized locomotion, stereotypic and autistic-like features, and spatial memory in Cdkl5 KO mice. These positive behavioral effects were accompanied by restored neuronal survival, dendritic development and synaptic connectivity. At a molecular level, sertraline increased brain-derived neurotrophic factor (BDNF) expression and restored abnormal phosphorylation levels of tyrosine kinase B (TrkB) and its downstream target the extracellular signal-regulated kinase (ERK1/2). Since sertraline is an FDA-approved drug with an extensive safety and tolerability data package, even for children, our findings suggest that sertraline may improve neurodevelopment in children with CDD. This article is part of the special issue entitled 'Serotonin Research: Crossing Scales and Boundaries'.
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Affiliation(s)
- Claudia Fuchs
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy.
| | - Laura Gennaccaro
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Elisa Ren
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Giuseppe Galvani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Giorgio Medici
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Manuela Loi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Erin Conway
- Department of Neurology, NYU Langone Health, New York, USA
| | - Orrin Devinsky
- Department of Neurology, NYU Langone Health, New York, USA
| | - Roberto Rimondini
- Department of Medical and Clinical Sciences, University of Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy.
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52
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Fazzari M, Frasca A, Bifari F, Landsberger N. Aminoglycoside drugs induce efficient read-through of CDKL5 nonsense mutations, slightly restoring its kinase activity. RNA Biol 2019; 16:1414-1423. [PMID: 31232219 DOI: 10.1080/15476286.2019.1632633] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
The X-linked CDKL5 gene codes for a kinase whose mutations have been associated with a suite of neurodevelopmental disorders generally characterized by early-onset epileptic encephalopathy and severe intellectual disability. The impact of these mutations on CDKL5 functions and brain development remain mainly unknown, although the importance of maintaining the catalytic activity is generally recognized. Since no cure exists for CDKL5 disorders, the demand for innovative therapies is a real emergency. The recent discovery that CDKL5 is dosage sensitive poses concerns on conventional protein and gene augmentative therapies. Thus, RNA-based therapeutic approaches might be preferred. We studied the efficacy of read-through therapy on CDKL5 premature termination codons (PTCs) that correspond roughly to 15% of all mutations. Our results provide the first demonstration that all tested CDKL5 nonsense mutations are efficiently suppressed by aminoglycoside drugs. The functional characterization of the restored full-length CDKL5 reveals that read-through proteins fully recover their subcellular localization, but only partially rescue their catalytic activity. Since read-through can cause amino acid substitution, CDKL5 patients carrying the PTC outside the catalytic domain might benefit more from a nonsense suppression therapy. Eventually, we demonstrate that non-aminoglycoside drugs, such as Ataluren (PTC124) and GJ072, are unable to induce read-through activity on CDKL5 PTCs. Although these drugs might be more effective in vivo, these results question the validity of the Ataluren phase 2 clinical trial that is currently ongoing on CDKL5 patients.
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Affiliation(s)
- Maria Fazzari
- Department of Medical Biotechnology and Translational Medicine, University of Milan , Segrate , Italy
| | - Angelisa Frasca
- Department of Medical Biotechnology and Translational Medicine, University of Milan , Segrate , Italy
| | - Francesco Bifari
- Department of Medical Biotechnology and Translational Medicine, University of Milan , Segrate , Italy
| | - Nicoletta Landsberger
- Department of Medical Biotechnology and Translational Medicine, University of Milan , Segrate , Italy
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53
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Yennawar M, White RS, Jensen FE. AMPA Receptor Dysregulation and Therapeutic Interventions in a Mouse Model of CDKL5 Deficiency Disorder. J Neurosci 2019; 39:4814-4828. [PMID: 30952813 PMCID: PMC6561688 DOI: 10.1523/jneurosci.2041-18.2019] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 03/13/2019] [Accepted: 03/27/2019] [Indexed: 01/28/2023] Open
Abstract
Pathogenic mutations in cyclin-dependent kinase-like 5 (CDKL5) result in CDKL5 deficiency disorder (CDD), a rare disease marked by early-life seizures, autistic behaviors, and intellectual disability. Although mouse models of CDD exhibit dendritic instability and alterations in synaptic scaffolding proteins, studies of glutamate receptor levels and function are limited. Here we used a novel mouse model of CDD, the Cdkl5R59X knock-in mouse (R59X), to investigate changes in synaptic glutamate receptor subunits and functional consequences. Male mice were used for all experiments to avoid the confounding effects of X-inactivation that would be present in female heterozygous mice. We showed that adult male R59X mice recapitulated the behavioral outcomes observed in other mouse models of CDD, including social deficits and memory and learning impairments, and exhibited decreased latency to seizure upon pentylenetetrazol administration. Furthermore, we observed a specific increase in GluA2-lacking α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid)-type glutamate receptors (AMPARs) in the adult R59X hippocampus, which is accompanied electrophysiologically by increased rectification ratio of AMPAR EPSCs and elevated early-phase long term potentiation (LTP). Finally, we showed that acute treatment with the GluA2-lacking AMPAR blocker IEM-1460 decreased AMPAR currents, and rescued social deficits, working memory impairments, and seizure behavior latency in R59X mice.SIGNIFICANCE STATEMENT CDKL5 deficiency disorder (CDD) is a rare disease marked by autistic-like behaviors, intellectual disability, and seizures. While synaptic dysfunction has been observed in mouse models of CDD, there is limited information on how synaptic alterations contribute to behavioral and functional changes in CDD. Here we reveal elevated hippocampal GluA2-lacking AMPAR expression in a novel mouse model of CDD that is accompanied by changes in synaptic AMPAR function and plasticity. We also show, for the first time, that acutely targeting GluA2-lacking AMPAR dysregulation rescues core synaptic and neurobehavioral deficits in CDD.
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MESH Headings
- Adult
- Animals
- Behavior, Animal
- Child, Preschool
- Disease Models, Animal
- Epileptic Syndromes/drug therapy
- Epileptic Syndromes/genetics
- Epileptic Syndromes/psychology
- Excitatory Postsynaptic Potentials/genetics
- Female
- Gene Knock-In Techniques
- Humans
- Learning Disabilities/genetics
- Learning Disabilities/psychology
- Male
- Memory Disorders/genetics
- Memory Disorders/psychology
- Mice
- Mice, Inbred C57BL
- Mice, Neurologic Mutants
- Mutation/genetics
- Protein Serine-Threonine Kinases/deficiency
- Protein Serine-Threonine Kinases/genetics
- Psychomotor Performance
- Receptors, AMPA/deficiency
- Receptors, AMPA/drug effects
- Receptors, AMPA/genetics
- Seizures/chemically induced
- Seizures/physiopathology
- Social Behavior
- Spasms, Infantile/drug therapy
- Spasms, Infantile/genetics
- Spasms, Infantile/psychology
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Affiliation(s)
| | - Rachel S White
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
| | - Frances E Jensen
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
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54
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Ren E, Roncacé V, Trazzi S, Fuchs C, Medici G, Gennaccaro L, Loi M, Galvani G, Ye K, Rimondini R, Aicardi G, Ciani E. Functional and Structural Impairments in the Perirhinal Cortex of a Mouse Model of CDKL5 Deficiency Disorder Are Rescued by a TrkB Agonist. Front Cell Neurosci 2019; 13:169. [PMID: 31114483 PMCID: PMC6503158 DOI: 10.3389/fncel.2019.00169] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 04/09/2019] [Indexed: 11/24/2022] Open
Abstract
Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a severe X-linked neurodevelopmental encephalopathy caused by mutations in the CDKL5 gene and characterized by early-onset epilepsy and intellectual and motor impairments. No cure is currently available for CDD patients, as limited knowledge of the pathology has hindered the development of therapeutics. Cdkl5 knockout (KO) mouse models, recently created to investigate the role of CDKL5 in the etiology of CDD, recapitulate various features of the disorder. Previous studies have shown alterations in synaptic plasticity and dendritic pattern in the cerebral cortex and in the hippocampus, but the knowledge of the molecular substrates underlying these alterations is still limited. Here, we have examined for the first time synaptic function and plasticity, dendritic morphology, and signal transduction pathways in the perirhinal cortex (PRC) of this mouse model. Being interconnected with a wide range of cortical and subcortical structures and involved in various cognitive processes, PRC provides a very interesting framework for examining how CDKL5 mutation leads to deficits at the synapse, circuit, and behavioral level. We found that long-term potentiation (LTP) was impaired, and that the TrkB/PLCγ1 pathway could be mechanistically involved in this alteration. PRC neurons in mutant mice showed a reduction in dendritic length, dendritic branches, PSD-95-positive puncta, GluA2-AMPA receptor levels, and spine density and maturation. These functional and structural deficits were associated with impairment in visual recognition memory. Interestingly, an in vivo treatment with a TrkB agonist (the 7,8-DHF prodrug R13) to trigger the TrkB/PLCγ1 pathway rescued defective LTP, dendritic pattern, PSD-95 and GluA2-AMPA receptor levels, and restored visual recognition memory in Cdkl5 KO mice. Present findings demonstrate a critical role of TrkB signaling in the synaptic development alterations due to CDKL5 mutation, and suggest the possibility of TrkB-targeted pharmacological interventions.
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Affiliation(s)
- Elisa Ren
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Vincenzo Roncacé
- Department for Life Quality Studies, University of Bologna, Bologna, Italy
| | - Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Claudia Fuchs
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Giorgio Medici
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Laura Gennaccaro
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Manuela Loi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Giuseppe Galvani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Keqiang Ye
- School of Medicine, Emory University, Atlanta, GA, United States
| | - Roberto Rimondini
- Department of Biomedical and Clinical Sciences, University of Bologna, Bologna, Italy
| | - Giorgio Aicardi
- Department for Life Quality Studies, University of Bologna, Bologna, Italy.,Interdepartmental Center "Luigi Galvani" for Integrated Studies of Bioinformatics, Biophysics and Biocomplexity, University of Bologna, Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
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55
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Ko A, Kang HC. Frequently Identified Genetic Developmental and Epileptic Encephalopathy: A Review Focusing on Precision Medicine. ANNALS OF CHILD NEUROLOGY 2019. [DOI: 10.26815/acn.2019.00066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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56
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Fuchs C, Medici G, Trazzi S, Gennaccaro L, Galvani G, Berteotti C, Ren E, Loi M, Ciani E. CDKL5 deficiency predisposes neurons to cell death through the deregulation of SMAD3 signaling. Brain Pathol 2019; 29:658-674. [PMID: 30793413 DOI: 10.1111/bpa.12716] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 02/18/2019] [Indexed: 12/11/2022] Open
Abstract
CDKL5 deficiency disorder (CDD) is a rare encephalopathy characterized by early onset epilepsy and severe intellectual disability. CDD is caused by mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene, a member of a highly conserved family of serine-threonine kinases. Only a few physiological substrates of CDKL5 are currently known, which hampers the discovery of therapeutic strategies for CDD. Here, we show that SMAD3, a primary mediator of TGF-β action, is a direct phosphorylation target of CDKL5 and that CDKL5-dependent phosphorylation promotes SMAD3 protein stability. Importantly, we found that restoration of the SMAD3 signaling through TGF-β1 treatment normalized defective neuronal survival and maturation in Cdkl5 knockout (KO) neurons. Moreover, we demonstrate that Cdkl5 KO neurons are more vulnerable to neurotoxic/excitotoxic stimuli. In vivo treatment with TGF-β1 prevents increased NMDA-induced cell death in hippocampal neurons from Cdkl5 KO mice, suggesting an involvement of the SMAD3 signaling deregulation in the neuronal susceptibility to excitotoxic injury of Cdkl5 KO mice. Our finding reveals a new function for CDKL5 in maintaining neuronal survival that could have important implications for susceptibility to neurodegeneration in patients with CDD.
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Affiliation(s)
- Claudia Fuchs
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Giorgio Medici
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Laura Gennaccaro
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Giuseppe Galvani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Chiara Berteotti
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Elisa Ren
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Manuela Loi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
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57
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Li W, Cao J, Liu J, Chu W, Zhang C, Chen S, Kang Z. Downregulation of CDKL1 suppresses neuroblastoma cell proliferation, migration and invasion. Cell Mol Biol Lett 2019; 24:19. [PMID: 30891073 PMCID: PMC6407201 DOI: 10.1186/s11658-019-0139-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 02/11/2019] [Indexed: 01/28/2023] Open
Abstract
Background Cyclin-dependent kinase-like 1 (CDKL1) is a member of the cell division control protein 2-related serine–threonine protein kinase family. It is known to occur in various malignant tumors, but its role in neuroblastoma (NB) remains unclear. Methods We constructed a CDKL1-silenced NB cell strain (SH-SY5Y) and used real-time PCR and western blotting to confirm the silencing. Functional analyses were performed using the MTT, colony-formation, FACS, wound-healing and transwell invasion assays. Results The expression of CDKL1 was significantly upregulated in NB tissue as compared to the adjacent normal tissue. CDKL1 knockdown significantly suppressed cell viability and colony formation ability. It also induced cell cycle G0/G1 phase arrest and apoptosis, and suppressed the migration and invasion ability of SH-SY5Y cells. CDKL1 knockdown decreased the CDK4, cyclin D1 and vimentin expression levels, and increased the caspase-3, PARP and E-cadherin expression levels in SH-SY5Y cells. Conclusions Our findings suggest that CDKL1 plays an important role in NB cell proliferation, migration and invasion. It might serve as a potential target for NB therapy.
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Affiliation(s)
- Weiyi Li
- 1Eye Hospital, China Academy of Chinese Medical Sciences, No 33 Lugu Road, Shijingshan district, Beijing, 100040 China
| | - Jing Cao
- Yinan Branch of Qilu Hospital of Shandong University, Linyi, Shandong China
| | - Jian Liu
- 1Eye Hospital, China Academy of Chinese Medical Sciences, No 33 Lugu Road, Shijingshan district, Beijing, 100040 China
| | - Wenli Chu
- 1Eye Hospital, China Academy of Chinese Medical Sciences, No 33 Lugu Road, Shijingshan district, Beijing, 100040 China
| | - Congqing Zhang
- 1Eye Hospital, China Academy of Chinese Medical Sciences, No 33 Lugu Road, Shijingshan district, Beijing, 100040 China
| | - Shuiling Chen
- 1Eye Hospital, China Academy of Chinese Medical Sciences, No 33 Lugu Road, Shijingshan district, Beijing, 100040 China
| | - Zefeng Kang
- 1Eye Hospital, China Academy of Chinese Medical Sciences, No 33 Lugu Road, Shijingshan district, Beijing, 100040 China
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58
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Trazzi S, De Franceschi M, Fuchs C, Bastianini S, Viggiano R, Lupori L, Mazziotti R, Medici G, Lo Martire V, Ren E, Rimondini R, Zoccoli G, Bartesaghi R, Pizzorusso T, Ciani E. CDKL5 protein substitution therapy rescues neurological phenotypes of a mouse model of CDKL5 disorder. Hum Mol Genet 2019; 27:1572-1592. [PMID: 29474534 DOI: 10.1093/hmg/ddy064] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 02/17/2018] [Indexed: 11/13/2022] Open
Abstract
Cyclin-dependent kinase like-5 (CDKL5) disorder is a rare neurodevelopmental disease caused by mutations in the CDKL5 gene. The consequent misexpression of the CDKL5 protein in the nervous system leads to a severe phenotype characterized by intellectual disability, motor impairment, visual deficits and early-onset epilepsy. No therapy is available for CDKL5 disorder. It has been reported that a protein transduction domain (TAT) is able to deliver macromolecules into cells and even into the brain when fused to a given protein. We demonstrate that TAT-CDKL5 fusion protein is efficiently internalized by target cells and retains CDKL5 activity. Intracerebroventricular infusion of TAT-CDKL5 restored hippocampal development, hippocampus-dependent memory and breathing pattern in Cdkl5-null mice. Notably, systemically administered TAT-CDKL5 protein passed the blood-brain-barrier, reached the CNS, and rescued various neuroanatomical and behavioral defects, including breathing pattern and visual responses. Our results suggest that CDKL5 protein therapy may be an effective clinical tool for the treatment of CDKL5 disorder.
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Affiliation(s)
- Stefania Trazzi
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Marianna De Franceschi
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Claudia Fuchs
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Stefano Bastianini
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Rocchina Viggiano
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Leonardo Lupori
- BIO@SNS lab, Scuola Normale Superiore di Pisa, 56125 Pisa, Italy
| | | | - Giorgio Medici
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Viviana Lo Martire
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Elisa Ren
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Roberto Rimondini
- Department of Medical and Clinical Sciences, University of Bologna, 40126 Bologna, Italy
| | - Giovanna Zoccoli
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Renata Bartesaghi
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Tommaso Pizzorusso
- BIO@SNS lab, Scuola Normale Superiore di Pisa, 56125 Pisa, Italy.,NEUROFARBA Department, University of Florence, 50139 Florence, Italy.,Institute of Neuroscience, CNR, 56125 Pisa, Italy
| | - Elisabetta Ciani
- 1Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
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59
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From molecules to medicines: the dawn of targeted therapies for genetic epilepsies. Nat Rev Neurol 2018; 14:735-745. [DOI: 10.1038/s41582-018-0099-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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60
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Zhu YC, Xiong ZQ. Molecular and Synaptic Bases of CDKL5 Disorder. Dev Neurobiol 2018; 79:8-19. [PMID: 30246934 DOI: 10.1002/dneu.22639] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 09/05/2018] [Accepted: 09/14/2018] [Indexed: 01/04/2023]
Abstract
The X-linked gene cyclin-dependent kinase-like 5 (CDKL5) encodes a serine/threonine kinase abundantly expressed in the brain. Mutations in CDKL5 have been associated with neurodevelopmental disorders characterized by early-onset epileptic encephalopathy and severe intellectual disability, suggesting that CDKL5 plays important roles in brain development and function. Recent studies using cultured neurons, knockout mice, and human iPSC-derived neurons have demonstrated that CDKL5 regulates axon outgrowth, dendritic morphogenesis, and synapse formation. The role of CDKL5 in maintaining synaptic function in the mature brain has also begun to emerge. Moreover, mouse models that are deficient for CDKL5 recapitulate some of the key clinical phenotypes in human patients. Here we review these findings related to the function of CDKL5 in the brain and discuss the underlying molecular and cellular mechanisms.
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Affiliation(s)
- Yong-Chuan Zhu
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zhi-Qi Xiong
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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61
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Vigli D, Rusconi L, Valenti D, La Montanara P, Cosentino L, Lacivita E, Leopoldo M, Amendola E, Gross C, Landsberger N, Laviola G, Kilstrup-Nielsen C, Vacca RA, De Filippis B. Rescue of prepulse inhibition deficit and brain mitochondrial dysfunction by pharmacological stimulation of the central serotonin receptor 7 in a mouse model of CDKL5 Deficiency Disorder. Neuropharmacology 2018; 144:104-114. [PMID: 30326240 DOI: 10.1016/j.neuropharm.2018.10.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/05/2018] [Accepted: 10/12/2018] [Indexed: 12/30/2022]
Abstract
Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene cause CDKL5 Deficiency Disorder (CDD), a rare neurodevelopmental syndrome characterized by severe behavioural and physiological symptoms. No cure is available for CDD. CDKL5 is a kinase that is abundantly expressed in the brain and plays a critical role in neurodevelopmental processes, such as neuronal morphogenesis and plasticity. This study provides the first characterization of the neurobehavioural phenotype of 1 year old Cdkl5-null mice and demonstrates that stimulation of the serotonin receptor 7 (5-HT7R) with the agonist molecule LP-211 (0.25 mg/kg once/day for 7 days) partially rescues the abnormal phenotype and brain molecular alterations in Cdkl5-null male mice. In particular, LP-211 treatment completely normalizes the prepulse inhibition defects observed in Cdkl5-null mice and, at a molecular level, restores the abnormal cortical phosphorylation of rpS6, a downstream target of mTOR and S6 kinase, which plays a direct role in regulating protein synthesis. Moreover, we demonstrate for the first time that mitochondria show prominent functional abnormalities in Cdkl5-null mouse brains that can be restored by pharmacological stimulation of brain 5-HT7R.
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Affiliation(s)
- Daniele Vigli
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy
| | - Laura Rusconi
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
| | - Daniela Valenti
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, National Council of Research, 70126 Bari, Italy
| | - Paolo La Montanara
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
| | - Livia Cosentino
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy
| | - Enza Lacivita
- Dept. Pharmacy, University of Bari "Aldo Moro", 70125 Bari, Italy
| | | | - Elena Amendola
- Molecular Medicine and Medical Biotechnologies, University of Naples "Federico II", 80131 Napoli, Italy
| | - Cornelius Gross
- Mouse Biology Unit, European Molecular Biology Laboratory (EMBL) 00015 Monterotondo, Italy
| | - Nicoletta Landsberger
- Department of Medical Biotechnology and Translational Medicine, University of Milan, 20090 Segrate, Italy
| | - Giovanni Laviola
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy
| | - Charlotte Kilstrup-Nielsen
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
| | - Rosa A Vacca
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, National Council of Research, 70126 Bari, Italy
| | - Bianca De Filippis
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy.
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Schroeder E, Yuan L, Seong E, Ligon C, DeKorver N, Gurumurthy CB, Arikkath J. Neuron-Type Specific Loss of CDKL5 Leads to Alterations in mTOR Signaling and Synaptic Markers. Mol Neurobiol 2018; 56:4151-4162. [PMID: 30288694 DOI: 10.1007/s12035-018-1346-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 09/06/2018] [Indexed: 11/27/2022]
Abstract
CDKL5 disorder is a devastating neurodevelopmental disorder associated with epilepsy, developmental retardation, autism, and related phenotypes. Mutations in the CDKL5 gene, encoding CDKL5, have been identified in this disorder. CDKL5 is a protein with homology to the serine-threonine kinases and incompletely characterized function. We generated and validated a murine model bearing a floxed allele of CDKL5 and polyclonal antibodies to CDKL5. CDKL5 is well expressed in the cortex, hippocampus, and striatum, localized to synaptosomes and nuclei and developmentally regulated in the hippocampus. Using Cre-mediated mechanisms, we deleted CDKL5 from excitatory CaMKIIα-positive neurons or inhibitory GABAergic neurons. Our data indicate that loss of CDKL5 in excitatory neurons of the cortex or inhibitory neurons of the striatum differentially alters expression of some components of the mechanistic target of rapamycin (mTOR) signaling pathway. Further loss of CDKL5 in excitatory neurons of the cortex or inhibitory neurons of the striatum leads to alterations in levels of synaptic markers in a neuron-type specific manner. Taken together, these data support a model in which loss of CDKL5 alters mTOR signaling and synaptic compositions in a neuron-type specific manner and suggest that CDKL5 may have distinct functional roles related to cellular signaling in excitatory and inhibitory neurons. Thus, these studies provide new insights into the biology of CDKL5 and suggest that the molecular pathology in CDKL5 disorder may have distinct neuron-type specific origins and effects.
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Affiliation(s)
- Ethan Schroeder
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Li Yuan
- Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Eunju Seong
- Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Cheryl Ligon
- Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Nicholas DeKorver
- Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - C B Gurumurthy
- Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Jyothi Arikkath
- Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
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Lim Z, Wong K, Downs J, Bebbington K, Demarest S, Leonard H. Vagus nerve stimulation for the treatment of refractory epilepsy in the CDKL5 Deficiency Disorder. Epilepsy Res 2018; 146:36-40. [DOI: 10.1016/j.eplepsyres.2018.07.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 07/17/2018] [Accepted: 07/22/2018] [Indexed: 12/24/2022]
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Baltussen LL, Rosianu F, Ultanir SK. Kinases in synaptic development and neurological diseases. Prog Neuropsychopharmacol Biol Psychiatry 2018; 84:343-352. [PMID: 29241837 DOI: 10.1016/j.pnpbp.2017.12.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 12/08/2017] [Accepted: 12/09/2017] [Indexed: 10/18/2022]
Abstract
Neuronal morphogenesis and synapse development is essential for building a functioning nervous system, and defects in these processes are associated with neurological disorders. Our understanding of molecular components and signalling events that contribute to neuronal development and pathogenesis is limited. Genes associated with neurodevelopmental and neurodegenerative diseases provide entry points for elucidating molecular events that contribute to these conditions. Several protein kinases, enzymes that regulate protein function by phosphorylating their substrates, are genetically linked to neurological disorders. Identifying substrates of these kinases is key to discovering their function and providing insight for possible therapies. In this review, we describe how various methods for kinase-substrate identification helped elucidate kinase signalling pathways important for neuronal development and function. We describe recent advances on roles of kinases TAOK2, TNIK and CDKL5 in neuronal development and the converging pathways of LRRK2, PINK1 and GAK in Parkinson's Disease.
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Affiliation(s)
- Lucas L Baltussen
- Kinases and Brain Development Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Flavia Rosianu
- Kinases and Brain Development Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Sila K Ultanir
- Kinases and Brain Development Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom.
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Heterozygous CDKL5 Knockout Female Mice Are a Valuable Animal Model for CDKL5 Disorder. Neural Plast 2018; 2018:9726950. [PMID: 29977282 PMCID: PMC5994305 DOI: 10.1155/2018/9726950] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 03/27/2018] [Accepted: 04/10/2018] [Indexed: 12/21/2022] Open
Abstract
CDKL5 disorder is a severe neurodevelopmental disorder caused by mutations in the X-linked CDKL5 (cyclin-dependent kinase-like five) gene. CDKL5 disorder primarily affects girls and is characterized by early-onset epileptic seizures, gross motor impairment, intellectual disability, and autistic features. Although all CDKL5 female patients are heterozygous, the most valid disease-related model, the heterozygous female Cdkl5 knockout (Cdkl5 +/−) mouse, has been little characterized. The lack of detailed behavioral profiling of this model remains a crucial gap that must be addressed in order to advance preclinical studies. Here, we provide a behavioral and molecular characterization of heterozygous Cdkl5 +/− mice. We found that Cdkl5 +/− mice reliably recapitulate several aspects of CDKL5 disorder, including autistic-like behaviors, defects in motor coordination and memory performance, and breathing abnormalities. These defects are associated with neuroanatomical alterations, such as reduced dendritic arborization and spine density of hippocampal neurons. Interestingly, Cdkl5 +/− mice show age-related alterations in protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) signaling, two crucial signaling pathways involved in many neurodevelopmental processes. In conclusion, our study provides a comprehensive overview of neurobehavioral phenotypes of heterozygous female Cdkl5 +/− mice and demonstrates that the heterozygous female might be a valuable animal model in preclinical studies on CDKL5 disorder.
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Okuda K, Takao K, Watanabe A, Miyakawa T, Mizuguchi M, Tanaka T. Comprehensive behavioral analysis of the Cdkl5 knockout mice revealed significant enhancement in anxiety- and fear-related behaviors and impairment in both acquisition and long-term retention of spatial reference memory. PLoS One 2018; 13:e0196587. [PMID: 29702698 PMCID: PMC5922552 DOI: 10.1371/journal.pone.0196587] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 04/16/2018] [Indexed: 12/27/2022] Open
Abstract
Mutations in the Cyclin-dependent kinase-like 5 (CDKL5) gene cause severe neurodevelopmental disorders. Recently we have generated Cdkl5 KO mice by targeting exon 2 on the C57BL/6N background, and demonstrated postsynaptic overaccumulation of GluN2B-containing N-methyl-D-aspartate (NMDA) receptors in the hippocampus. In the current study, we subjected the Cdkl5 KO mice to a battery of comprehensive behavioral tests, aiming to reveal the effects of loss of CDKL5 in a whole perspective of motor, emotional, social, and cognition/memory functions, and to identify its undetermined roles. The neurological screen, rotarod, hot plate, prepulse inhibition, light/dark transition, open field, elevated plus maze, Porsolt forced swim, tail suspension, one-chamber and three-chamber social interaction, 24-h home cage monitoring, contextual and cued fear conditioning, Barnes maze, and T-maze tests were applied on adult Cdkl5 -/Y and +/Y mice. Cdkl5 -/Y mice showed a mild alteration in the gait. Analyses of emotional behaviors revealed significantly enhanced anxiety-like behaviors of Cdkl5 -/Y mice. Depressive-like behaviors and social interaction of Cdkl5 -/Y mice were uniquely altered. The contextual and cued fear conditioning of Cdkl5 -/Y mice were comparable to control mice; however, Cdkl5 -/Y mice showed a significantly increased freezing time and a significantly decreased distance traveled during the pretone period in the altered context. Both acquisition and long-term retention of spatial reference memory were significantly impaired. The morphometric analysis of hippocampal CA1 pyramidal neurons revealed impaired dendritic arborization and immature spine development in Cdkl5 -/Y mice. These results indicate that CDKL5 plays significant roles in regulating emotional behaviors especially on anxiety- and fear-related responses, and in both acquisition and long-term retention of spatial reference memory, which suggests that focus and special attention should be paid to the specific mechanisms of these deficits in the CDKL5 deficiency disorder.
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Affiliation(s)
- Kosuke Okuda
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Keizo Takao
- Section of Behavior Patterns, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
| | - Aya Watanabe
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Tsuyoshi Miyakawa
- Section of Behavior Patterns, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
- Division of Systems Medical Science, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi, Japan
| | - Masashi Mizuguchi
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Teruyuki Tanaka
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- * E-mail:
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Fuchs C, Fustini N, Trazzi S, Gennaccaro L, Rimondini R, Ciani E. Treatment with the GSK3-beta inhibitor Tideglusib improves hippocampal development and memory performance in juvenile, but not adult, Cdkl5 knockout mice. Eur J Neurosci 2018; 47:1054-1066. [PMID: 29603837 DOI: 10.1111/ejn.13923] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 03/13/2017] [Accepted: 03/22/2018] [Indexed: 01/21/2023]
Abstract
Cyclin-dependent kinase-like 5 (CDKL5) disorder is a severe neurodevelopmental disorder characterized by early-onset epileptic seizures, severe developmental delay, and intellectual disability. To date, no effective pharmacological treatments are available to improve the neurological phenotype that is due to mutations in the CDKL5 gene. Murine models of CDKL5 disorder have recently been generated, making the preclinical testing of pharmacological interventions possible. Using a Cdkl5 knockout (KO) mouse model, we recently demonstrated that deficiency of Cdkl5 causes defects in postnatal hippocampal development and hippocampus-dependent learning and memory. These defects were accompanied by an increased activity of GSK3β, an important inhibitory regulator of many neuronal functions. Pharmacological inhibition of GSK3β activity was able to recover hippocampal defects and cognitive performance in juvenile Cdkl5 KO mice, suggesting that GSK3β inhibitors might be a potential therapeutic option for CDKL5 disorder. As GSK3β inhibitors have been shown to have differential medication responses in young people and adults, this study was designed to examine whether GSK3β is a possible therapeutic target both in juvenile and in adult CDKL5 patients. We found that treatment with the GSK3β inhibitor Tideglusib during the juvenile period improved hippocampal development and hippocampus-dependent behaviors in Cdkl5 KO mice, while treatment later on in adulthood had no positive effects. These results suggest that pharmacological interventions aimed at normalizing impaired GSK3β activity might have different age-dependent outcomes in CDKL5 disorder. This is of utmost importance in the development of therapeutic approaches in CDKL5 patients and in the design of rational clinical trials.
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Affiliation(s)
- Claudia Fuchs
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, 40126, Italy
| | - Norma Fustini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, 40126, Italy
| | - Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, 40126, Italy
| | - Laura Gennaccaro
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, 40126, Italy
| | - Roberto Rimondini
- Department of Medical and Clinical Sciences, University of Bologna, Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, 40126, Italy
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68
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Jhang CL, Huang TN, Hsueh YP, Liao W. Mice lacking cyclin-dependent kinase-like 5 manifest autistic and ADHD-like behaviors. Hum Mol Genet 2018; 26:3922-3934. [PMID: 29016850 DOI: 10.1093/hmg/ddx279] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 07/10/2017] [Indexed: 01/02/2023] Open
Abstract
Neurodevelopmental disorders frequently share common clinical features and appear high rate of comorbidity, such as those present in patients with attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorders (ASD). While characterizing behavioral phenotypes in the mouse model of cyclin-dependent kinase-like 5 (CDKL5) disorder, a neurodevelopmental disorder caused by mutations in the X-linked gene encoding CDKL5, we found that these mice manifested behavioral phenotypes mimicking multiple key features of ASD, such as impaired social interaction and communication, as well as increased stereotypic digging behaviors. These mice also displayed hyper-locomotion, increased aggressiveness and impulsivity, plus deficits in motor and associative learning, resembling primary symptoms of ADHD. Through brain region-specific biochemical analysis, we uncovered that loss of CDKL5 disrupts dopamine synthesis and the expression of social communication-related key genes, such as forkhead-box P2 and mu-opioid receptor, in the corticostriatal circuit. Together, our findings support that CDKL5 plays a role in the comorbid features of autism and ADHD, and mice lacking CDKL5 may serve as an animal model to study the molecular and circuit mechanisms underlying autism-ADHD comorbidity.
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Affiliation(s)
- Cian-Ling Jhang
- Institute of Neuroscience, National Cheng-Chi University, Taipei 116, Taiwan
| | - Tzyy-Nan Huang
- Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan
| | - Wenlin Liao
- Institute of Neuroscience, National Cheng-Chi University, Taipei 116, Taiwan.,Research Center for Mind, Brain and Learning, National Cheng-Chi University, Taipei 116, Taiwan
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Abstract
The tragedy of epilepsy emerges from the combination of its high prevalence, impact upon sufferers and their families, and unpredictability. Childhood epilepsies are frequently severe, presenting in infancy with pharmaco-resistant seizures; are often accompanied by debilitating neuropsychiatric and systemic comorbidities; and carry a grave risk of mortality. Here, we review the most current basic science and translational research findings on several of the most catastrophic forms of pediatric epilepsy. We focus largely on genetic epilepsies and the research that is discovering the mechanisms linking disease genes to epilepsy syndromes. We also describe the strides made toward developing novel pharmacological and interventional treatment strategies to treat these disorders. The research reviewed provides hope for a complete understanding of, and eventual cure for, these childhood epilepsy syndromes.
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Affiliation(s)
- MacKenzie A Howard
- Center for Learning and Memory and Department of Neuroscience, University of Texas at Austin, Texas, 78712;
| | - Scott C Baraban
- Epilepsy Research Laboratory in the Department of Neurological Surgery, Weill Institute for Neurosciences, University of California, San Francisco, California 94143;
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70
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Gao HL, Li C, Nabeka H, Shimokawa T, Wang ZY, Cao YM, Matsuda S. An 18-mer Peptide Derived from Prosaposin Ameliorates the Effects of Aβ1-42 Neurotoxicity on Hippocampal Neurogenesis and Memory Deficit in Mice. J Alzheimers Dis 2018; 53:1173-92. [PMID: 27372641 DOI: 10.3233/jad-160093] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The pathological hallmarks of Alzheimer's disease (AD) include amyloid-β (Aβ) accumulation, neurofibrillary tangle formation, synaptic dysfunction, and neuronal loss. The present study was performed to investigate the protective effects and mechanism of action of a prosaposin-derived 18-mer peptide (PS18: LSELIINNATEELLIKGL) on mice hippocampal progenitor cell proliferation, neurogenesis, and memory tasks after intracerebroventricular injection of Aβ1-42 peptide. Seven days after Aβ1-42 injection, significant proliferation of hippocampal progenitor cells and memory impairment were evident. Two weeks after Aβ1-42 peptide injection, elevated numbers of surviving 5-bromo-2-deoxyuridine cells and newly formed neurons were detected. Treatment with PS18 attenuated these effects evoked by Aβ1-42. Our data indicate that treatment with PS18 partially attenuated the increase in hippocampal neurogenesis caused by Aβ1-42-induced neuroinflammation and prevented memory deficits associated with increased numbers of activated glial cells. We observed an increase in ADAM10 and decreases in BACE1, PS1/2, and AβPP protein levels, suggesting that PS18 enhances the nonamyloidogenic AβPP cleavage pathway. Importantly, our results further showed that PS18 activated the PI3K/Akt pathway, phosphorylated GSK-3α/β, and, as a consequence, exerted a neuroprotective effect. In addition, PS18 showed a protective effect against Aβ1-42-induced neurotoxicity via suppression of the caspase pathway; upregulation of Bcl-2; downregulation of BAX, attenuating mitochondrial damage; and inhibition of caspase-3. These findings suggest that PS18 may provide a valuable therapeutic strategy for the treatment of progressive neurodegenerative diseases, such as AD.
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Affiliation(s)
- Hui-Ling Gao
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Cheng Li
- Department of Immunology, China Medical University, Shenyang, China
| | - Hiroaki Nabeka
- Department of Anatomy and Embryology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
| | - Tetsuya Shimokawa
- Department of Anatomy and Embryology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
| | - Zhan-You Wang
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Ya-Ming Cao
- Department of Immunology, China Medical University, Shenyang, China
| | - Seiji Matsuda
- Department of Anatomy and Embryology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
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Canning P, Park K, Gonçalves J, Li C, Howard CJ, Sharpe TD, Holt LJ, Pelletier L, Bullock AN, Leroux MR. CDKL Family Kinases Have Evolved Distinct Structural Features and Ciliary Function. Cell Rep 2018; 22:885-894. [PMID: 29420175 PMCID: PMC5846859 DOI: 10.1016/j.celrep.2017.12.083] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 11/07/2017] [Accepted: 12/22/2017] [Indexed: 12/28/2022] Open
Abstract
Various kinases, including a cyclin-dependent kinase (CDK) family member, regulate the growth and functions of primary cilia, which perform essential roles in signaling and development. Neurological disorders linked to CDK-Like (CDKL) proteins suggest that these underexplored kinases may have similar functions. Here, we present the crystal structures of human CDKL1, CDKL2, CDKL3, and CDKL5, revealing their evolutionary divergence from CDK and mitogen-activated protein kinases (MAPKs), including an unusual ?J helix important for CDKL2 and CDKL3 activity. C. elegans CDKL-1, most closely related to CDKL1-4 and localized to neuronal cilia transition zones, modulates cilium length; this depends on its kinase activity and ?J helix-containing C terminus. Human CDKL5, linked to Rett syndrome, also localizes to cilia, and it impairs ciliogenesis when overexpressed. CDKL5 patient mutations modeled in CDKL-1 cause localization and/or cilium length defects. Together, our studies establish a disease model system suggesting cilium length defects as a pathomechanism for neurological disorders, including epilepsy.
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Affiliation(s)
- Peter Canning
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Kwangjin Park
- Department of Molecular Biology and Biochemistry, and Centre for Cell Biology, Development, and Disease, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - João Gonçalves
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Chunmei Li
- Department of Molecular Biology and Biochemistry, and Centre for Cell Biology, Development, and Disease, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Conor J Howard
- Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Timothy D Sharpe
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Liam J Holt
- Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Laurence Pelletier
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Alex N Bullock
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, UK.
| | - Michel R Leroux
- Department of Molecular Biology and Biochemistry, and Centre for Cell Biology, Development, and Disease, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
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Barbiero I, Peroni D, Tramarin M, Chandola C, Rusconi L, Landsberger N, Kilstrup-Nielsen C. The neurosteroid pregnenolone reverts microtubule derangement induced by the loss of a functional CDKL5-IQGAP1 complex. Hum Mol Genet 2018. [PMID: 28641386 DOI: 10.1093/hmg/ddx237] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
CDKL5 is a protein kinase that plays a key role for neuronal functions as testified by the onset of complex neuronal dysfunctions in patients with genetic lesions in CDKL5. Here we identify a novel interactor of CDKL5, IQGAP1, a fundamental regulator of cell migration and polarity. In accordance with a functional role of this interaction, depletion of CDKL5 impairs cell migration and impedes the localization of IQGAP1 at the leading edge. Moreover, we demonstrate that CDKL5 is required for IQGAP1 to form a functional complex with its effectors, Rac1 and the microtubule plus end tracking protein CLIP170. These defects eventually impact on the microtubule association of CLIP170, thus deranging their dynamics. CLIP170 is a cellular target of the neurosteroid pregnenolone; by blocking CLIP170 in its active conformation, pregnenolone is capable of restoring the microtubule association of CLIP170 in CDKL5 deficient cells and rescuing morphological defects in neurons devoid of CDKL5. These findings provide novel insights into CDKL5 functions and pave the way for target-specific therapeutic strategies for individuals affected with CDKL5-disorder.
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Affiliation(s)
- Isabella Barbiero
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
| | - Diana Peroni
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
| | - Marco Tramarin
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
| | - Chetan Chandola
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
| | - Laura Rusconi
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
| | - Nicoletta Landsberger
- Department of Medical Biotechnology and Translational Medicine, University of Milan, 20129 Milan, Italy
| | - Charlotte Kilstrup-Nielsen
- Department of Biotechnology and Life Sciences and Center of Neuroscience, University of Insubria, 21052 Busto Arsizio, Italy
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CDKL5 localizes at the centrosome and midbody and is required for faithful cell division. Sci Rep 2017; 7:6228. [PMID: 28740074 PMCID: PMC5524905 DOI: 10.1038/s41598-017-05875-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 06/05/2017] [Indexed: 02/02/2023] Open
Abstract
The cyclin-dependent kinase-like 5 (CDKL5) gene has been associated with rare neurodevelopmental disorders characterized by the early onset of seizures and intellectual disability. The CDKL5 protein is widely expressed in most tissues and cells with both nuclear and cytoplasmic localization. In post-mitotic neurons CDKL5 is mainly involved in dendritic arborization, axon outgrowth, and spine formation while in proliferating cells its function is still largely unknown. Here, we report that CDKL5 localizes at the centrosome and at the midbody in proliferating cells. Acute inactivation of CDKL5 by RNA interference (RNAi) leads to multipolar spindle formation, cytokinesis failure and centrosome accumulation. At the molecular level, we observed that, among the several midbody components we analyzed, midbodies of CDKL5-depleted cells were devoid of HIPK2 and its cytokinesis target, the extrachromosomal histone H2B phosphorylated at S14. Of relevance, expression of the phosphomimetic mutant H2B-S14D, which is capable of overcoming cytokinesis failure in HIPK2-defective cells, was sufficient to rescue spindle multipolarity in CDKL5-depleted cells. Taken together, these results highlight a hitherto unknown role of CDKL5 in regulating faithful cell division by guaranteeing proper HIPK2/H2B functions at the midbody.
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74
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Okuda K, Kobayashi S, Fukaya M, Watanabe A, Murakami T, Hagiwara M, Sato T, Ueno H, Ogonuki N, Komano-Inoue S, Manabe H, Yamaguchi M, Ogura A, Asahara H, Sakagami H, Mizuguchi M, Manabe T, Tanaka T. CDKL5 controls postsynaptic localization of GluN2B-containing NMDA receptors in the hippocampus and regulates seizure susceptibility. Neurobiol Dis 2017; 106:158-170. [PMID: 28688852 DOI: 10.1016/j.nbd.2017.07.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 06/10/2017] [Accepted: 07/02/2017] [Indexed: 12/21/2022] Open
Abstract
Mutations in the Cyclin-dependent kinase-like 5 (CDKL5) gene cause severe neurodevelopmental disorders accompanied by intractable epilepsies, i.e. West syndrome or atypical Rett syndrome. Here we report generation of the Cdkl5 knockout mouse and show that CDKL5 controls postsynaptic localization of GluN2B-containing N-methyl-d-aspartate (NMDA) receptors in the hippocampus and regulates seizure susceptibility. Cdkl5 -/Y mice showed normal sensitivity to kainic acid; however, they displayed significant hyperexcitability to NMDA. In concordance with this result, electrophysiological analysis in the hippocampal CA1 region disclosed an increased ratio of NMDA/α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated excitatory postsynaptic currents (EPSCs) and a significantly larger decay time constant of NMDA receptor-mediated EPSCs (NMDA-EPSCs) as well as a stronger inhibition of the NMDA-EPSCs by the GluN2B-selective antagonist ifenprodil in Cdkl5 -/Y mice. Subcellular fractionation of the hippocampus from Cdkl5 -/Y mice revealed a significant increase of GluN2B and SAP102 in the PSD (postsynaptic density)-1T fraction, without changes in the S1 (post-nuclear) fraction or mRNA transcripts, indicating an intracellular distribution shift of these proteins to the PSD. Immunoelectron microscopic analysis of the hippocampal CA1 region further confirmed postsynaptic overaccumulation of GluN2B and SAP102 in Cdkl5 -/Y mice. Furthermore, ifenprodil abrogated the NMDA-induced hyperexcitability in Cdkl5 -/Y mice, suggesting that upregulation of GluN2B accounts for the enhanced seizure susceptibility. These data indicate that CDKL5 plays an important role in controlling postsynaptic localization of the GluN2B-SAP102 complex in the hippocampus and thereby regulates seizure susceptibility, and that aberrant NMDA receptor-mediated synaptic transmission underlies the pathological mechanisms of the CDKL5 loss-of-function.
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Affiliation(s)
- Kosuke Okuda
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Shizuka Kobayashi
- Division of Neuronal Network, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| | - Masahiro Fukaya
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara 252-0374, Japan
| | - Aya Watanabe
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Takuto Murakami
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Mai Hagiwara
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Tempei Sato
- Department of Systems Biomedicine, National Research Institute for Child Health and Development, Tokyo 157-8535, Japan
| | - Hiroe Ueno
- Department of Systems Biomedicine, National Research Institute for Child Health and Development, Tokyo 157-8535, Japan
| | - Narumi Ogonuki
- Bioresource Engineering Division, RIKEN BioResource Center, Tsukuba 305-0074, Japan
| | - Sayaka Komano-Inoue
- Department of Physiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Hiroyuki Manabe
- Department of Physiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Masahiro Yamaguchi
- Department of Physiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Atsuo Ogura
- Bioresource Engineering Division, RIKEN BioResource Center, Tsukuba 305-0074, Japan
| | - Hiroshi Asahara
- Department of Systems Biomedicine, National Research Institute for Child Health and Development, Tokyo 157-8535, Japan; Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla 92037, USA
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara 252-0374, Japan
| | - Masashi Mizuguchi
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Toshiya Manabe
- Division of Neuronal Network, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| | - Teruyuki Tanaka
- Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan.
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Loss of CDKL5 in Glutamatergic Neurons Disrupts Hippocampal Microcircuitry and Leads to Memory Impairment in Mice. J Neurosci 2017; 37:7420-7437. [PMID: 28674172 DOI: 10.1523/jneurosci.0539-17.2017] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Revised: 06/15/2017] [Accepted: 06/22/2017] [Indexed: 01/23/2023] Open
Abstract
Cyclin-dependent kinase-like 5 (CDKL5) deficiency is a neurodevelopmental disorder characterized by epileptic seizures, severe intellectual disability, and autistic features. Mice lacking CDKL5 display multiple behavioral abnormalities reminiscent of the disorder, but the cellular origins of these phenotypes remain unclear. Here, we find that ablating CDKL5 expression specifically from forebrain glutamatergic neurons impairs hippocampal-dependent memory in male conditional knock-out mice. Hippocampal pyramidal neurons lacking CDKL5 show decreased dendritic complexity but a trend toward increased spine density. This morphological change is accompanied by an increase in the frequency of spontaneous miniature EPSCs and interestingly, miniature IPSCs. Using voltage-sensitive dye imaging to interrogate the evoked response of the CA1 microcircuit, we find that CA1 pyramidal neurons lacking CDKL5 show hyperexcitability in their dendritic domain that is constrained by elevated inhibition in a spatially and temporally distinct manner. These results suggest a novel role for CDKL5 in the regulation of synaptic function and uncover an intriguing microcircuit mechanism underlying impaired learning and memory.SIGNIFICANCE STATEMENT Cyclin-dependent kinase-like 5 (CDKL5) deficiency is a severe neurodevelopmental disorder caused by mutations in the CDKL5 gene. Although Cdkl5 constitutive knock-out mice have recapitulated key aspects of human symptomatology, the cellular origins of CDKL5 deficiency-related phenotypes are unknown. Here, using conditional knock-out mice, we show that hippocampal-dependent learning and memory deficits in CDKL5 deficiency have origins in glutamatergic neurons of the forebrain and that loss of CDKL5 results in the enhancement of synaptic transmission and disruptions in neural circuit dynamics in a spatially and temporally specific manner. Our findings demonstrate that CDKL5 is an important regulator of synaptic function in glutamatergic neurons and serves a critical role in learning and memory.
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Lim Z, Wong K, Olson HE, Bergin AM, Downs J, Leonard H. Use of the ketogenic diet to manage refractory epilepsy in CDKL5 disorder: Experience of >100 patients. Epilepsia 2017; 58:1415-1422. [PMID: 28605011 DOI: 10.1111/epi.13813] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/10/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Zhan Lim
- Telethon Kids Institute; University of Western Australia; West Perth Western Australia Australia
| | - Kingsley Wong
- Telethon Kids Institute; University of Western Australia; West Perth Western Australia Australia
| | - Heather E. Olson
- Division of Epilepsy and Clinical Neurophysiology; Department of Neurology; Boston Children's Hospital; Boston Massachusetts U.S.A
| | - Ann M. Bergin
- Division of Epilepsy and Clinical Neurophysiology; Department of Neurology; Boston Children's Hospital; Boston Massachusetts U.S.A
| | - Jenny Downs
- Telethon Kids Institute; University of Western Australia; West Perth Western Australia Australia
- School of Physiotherapy and Exercise Science; Curtin University; Perth Western Australia Australia
| | - Helen Leonard
- Telethon Kids Institute; University of Western Australia; West Perth Western Australia Australia
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Wang Y, Li Y, Xing Q, Han XG, Dong X, Lu Y, Zhou M. Sevoflurane anesthesia in pregnant rats negatively affects nerve function in offspring potentially via inhibition of the Wnt/β-catenin pathway. Mol Med Rep 2017; 15:2753-2759. [PMID: 28447764 DOI: 10.3892/mmr.2017.6316] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 01/10/2017] [Indexed: 11/06/2022] Open
Abstract
Due to the rapid development of medical technology used to perform intrauterine procedures during pregnancy, the number of patients receiving fetal surgery under general anesthesia is increasing. The aim of the present study was to determine the effects of anesthetics on the offspring of rats, and to identify the potential mechanisms underlying these effects. On day 14 of pregnancy, Sprague‑Dawley rats were equally divided into the following 3 groups (n=9): Control group (n=3), 3% sevoflurane group (n=3) and 4% sevoflurane group (n=3). Following birth of the offspring, the juvenile rats were assessed using an open‑field test, Morris water maze and a continuous passive avoidance test on different days to determine their learning abilities and memory. Western blot and reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analyses were used to examine the expression of multiple critical factors associated with the proliferation and apoptosis of nerve cells, including Ki67, nestin, B cell leukemia/lymphoma 2 (Bcl-2), BCL2 associated X (Bax) and caspase‑3. Additionally, the level of adenosine triphosphate production among the 3 groups were compared. Furthermore, expression alterations in of glycogen synthase kinase‑3β (GSK‑3β) and β‑catenin were examined. The Morris water maze experiment revealed that an increased concentration of sevoflurane exposure significantly reduced the learning and memory abilities of the juvenile rats when compared with controls. In addition, western blotting and RT-qPCR analyses determined that the protein and mRNA expression levels of Bax, caspase‑3 and GSK‑3β were significantly increased relative to the controls. By contrast, the expression levels of nestin, Ki‑67, Bcl‑2 and β‑catenin were significantly reduced. The results of the present study suggest that exposure of pregnant mice to sevoflurane anesthesia demonstrates a negative effect on the learning and memory abilities of their offspring, and the Wnt/β-catenin signaling pathway may be involved in this process.
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Affiliation(s)
- Yiyao Wang
- Department of Anesthesiology, The First Affiliated Hospital and College of Clinical Medicine, Henan University of Science and Technology, Luoyang, Henan 471003, P.R. China
| | - Yu Li
- Department of Anesthesiology, The First Affiliated Hospital and College of Clinical Medicine, Henan University of Science and Technology, Luoyang, Henan 471003, P.R. China
| | - Qunzhi Xing
- Department of Anesthesiology, The First Affiliated Hospital and College of Clinical Medicine, Henan University of Science and Technology, Luoyang, Henan 471003, P.R. China
| | - Xuechan G Han
- Department of Anesthesiology, The First Affiliated Hospital and College of Clinical Medicine, Henan University of Science and Technology, Luoyang, Henan 471003, P.R. China
| | - Xu Dong
- Department of Anesthesiology, The First Affiliated Hospital and College of Clinical Medicine, Henan University of Science and Technology, Luoyang, Henan 471003, P.R. China
| | - Yiping Lu
- Department of Anesthesiology, The First Affiliated Hospital and College of Clinical Medicine, Henan University of Science and Technology, Luoyang, Henan 471003, P.R. China
| | - Mintao Zhou
- Department of Anesthesiology, The First Affiliated Hospital and College of Clinical Medicine, Henan University of Science and Technology, Luoyang, Henan 471003, P.R. China
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Pfisterer U, Khodosevich K. Neuronal survival in the brain: neuron type-specific mechanisms. Cell Death Dis 2017; 8:e2643. [PMID: 28252642 PMCID: PMC5386560 DOI: 10.1038/cddis.2017.64] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 01/24/2017] [Accepted: 01/31/2017] [Indexed: 12/19/2022]
Abstract
Neurogenic regions of mammalian brain produce many more neurons that will eventually survive and reach a mature stage. Developmental cell death affects both embryonically produced immature neurons and those immature neurons that are generated in regions of adult neurogenesis. Removal of substantial numbers of neurons that are not yet completely integrated into the local circuits helps to ensure that maturation and homeostatic function of neuronal networks in the brain proceed correctly. External signals from brain microenvironment together with intrinsic signaling pathways determine whether a particular neuron will die. To accommodate this signaling, immature neurons in the brain express a number of transmembrane factors as well as intracellular signaling molecules that will regulate the cell survival/death decision, and many of these factors cease being expressed upon neuronal maturation. Furthermore, pro-survival factors and intracellular responses depend on the type of neuron and region of the brain. Thus, in addition to some common neuronal pro-survival signaling, different types of neurons possess a variety of 'neuron type-specific' pro-survival constituents that might help them to adapt for survival in a certain brain region. This review focuses on how immature neurons survive during normal and impaired brain development, both in the embryonic/neonatal brain and in brain regions associated with adult neurogenesis, and emphasizes neuron type-specific mechanisms that help to survive for various types of immature neurons. Importantly, we mainly focus on in vivo data to describe neuronal survival specifically in the brain, without extrapolating data obtained in the PNS or spinal cord, and thus emphasize the influence of the complex brain environment on neuronal survival during development.
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Affiliation(s)
- Ulrich Pfisterer
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Konstantin Khodosevich
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
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79
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Zhou A, Han S, Zhou ZJ. Molecular and genetic insights into an infantile epileptic encephalopathy - CDKL5 disorder. ACTA ACUST UNITED AC 2017; 12:1-6. [PMID: 28580010 DOI: 10.1007/s11515-016-1438-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND The discovery that mutations in cyclin-dependent kinase-like 5 (CDKL5) gene are associated with infantile epileptic encephalopathy has stimulated world-wide research effort to understand the molecular and genetic basis of CDKL5 disorder. Given the large number of literature published thus far, this review aims to summarize current genetic studies, draw a consensus on proposed molecular functions, and point to gaps of knowledge in CDKL5 research. METHODS A systematic review process was conducted using the PubMed search engine focusing on CDKL5 studies in the recent ten years. We analyzed these publications and summarized the findings into four sections: genetic studies, CDKL5 expression patterns, molecular functions, and animal models. We also discussed challenges and future directions in each section. RESULTS On the clinical side, CDKL5 disorder is characterized by early onset epileptic seizures, intellectual disability, and stereotypical behaviors. On the research side, a series of molecular and genetic studies in human patients, cell cultures and animal models have established the causality of CDKL5 to the infantile epileptic encephalopathy, and pointed to a key role for CDKL5 in regulating neuronal function in the brain. Mouse models of CDKL5 disorder have also been developed, and notably, manifest behavioral phenotypes, mimicking numerous clinical symptoms of CDKL5 disorder and advancing CDKL5 research to the preclinical stage. CONCLUSIONS Given what we have learned thus far, future identification of robust, quantitative, and sensitive outcome measures would be the key in animal model studies, particularly in heterozygous females. In the meantime, molecular and cellular studies of CDKL5 should focus on mechanism-based investigation and aim to uncover druggable targets that offer the potential to rescue or ameliorate CDKL5 disorder-related phenotypes.
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Affiliation(s)
- Ailing Zhou
- Jiaozhou People's Hospital, Jiaozhou, Shangdong 266300, China
| | - Song Han
- Jiaozhou People's Hospital, Jiaozhou, Shangdong 266300, China
| | - Zhaolan Joe Zhou
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
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80
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Lin YC, Frei JA, Kilander MBC, Shen W, Blatt GJ. A Subset of Autism-Associated Genes Regulate the Structural Stability of Neurons. Front Cell Neurosci 2016; 10:263. [PMID: 27909399 PMCID: PMC5112273 DOI: 10.3389/fncel.2016.00263] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 10/28/2016] [Indexed: 12/15/2022] Open
Abstract
Autism spectrum disorder (ASD) comprises a range of neurological conditions that affect individuals’ ability to communicate and interact with others. People with ASD often exhibit marked qualitative difficulties in social interaction, communication, and behavior. Alterations in neurite arborization and dendritic spine morphology, including size, shape, and number, are hallmarks of almost all neurological conditions, including ASD. As experimental evidence emerges in recent years, it becomes clear that although there is broad heterogeneity of identified autism risk genes, many of them converge into similar cellular pathways, including those regulating neurite outgrowth, synapse formation and spine stability, and synaptic plasticity. These mechanisms together regulate the structural stability of neurons and are vulnerable targets in ASD. In this review, we discuss the current understanding of those autism risk genes that affect the structural connectivity of neurons. We sub-categorize them into (1) cytoskeletal regulators, e.g., motors and small RhoGTPase regulators; (2) adhesion molecules, e.g., cadherins, NCAM, and neurexin superfamily; (3) cell surface receptors, e.g., glutamatergic receptors and receptor tyrosine kinases; (4) signaling molecules, e.g., protein kinases and phosphatases; and (5) synaptic proteins, e.g., vesicle and scaffolding proteins. Although the roles of some of these genes in maintaining neuronal structural stability are well studied, how mutations contribute to the autism phenotype is still largely unknown. Investigating whether and how the neuronal structure and function are affected when these genes are mutated will provide insights toward developing effective interventions aimed at improving the lives of people with autism and their families.
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Affiliation(s)
- Yu-Chih Lin
- Laboratory of Neuronal Connectivity, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
| | - Jeannine A Frei
- Laboratory of Neuronal Connectivity, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
| | - Michaela B C Kilander
- Laboratory of Neuronal Connectivity, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
| | - Wenjuan Shen
- Laboratory of Neuronal Connectivity, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
| | - Gene J Blatt
- Laboratory of Autism Neurocircuitry, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
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81
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Current understanding and neurobiology of epileptic encephalopathies. Neurobiol Dis 2016; 92:72-89. [DOI: 10.1016/j.nbd.2016.03.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 03/01/2016] [Accepted: 03/09/2016] [Indexed: 12/25/2022] Open
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82
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Trazzi S, Fuchs C, Viggiano R, De Franceschi M, Valli E, Jedynak P, Hansen FK, Perini G, Rimondini R, Kurz T, Bartesaghi R, Ciani E. HDAC4: a key factor underlying brain developmental alterations in CDKL5 disorder. Hum Mol Genet 2016; 25:3887-3907. [PMID: 27466189 DOI: 10.1093/hmg/ddw231] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 07/07/2016] [Accepted: 07/08/2016] [Indexed: 12/12/2022] Open
Abstract
Cyclin-dependent kinase-like 5 (CDKL5) is a Ser/Thr protein kinase predominantly expressed in the brain. Mutations of the CDKL5 gene lead to CDKL5 disorder, a neurodevelopmental pathology that shares several features with Rett Syndrome and is characterized by severe intellectual disability. The phosphorylation targets of CDKL5 are largely unknown, which hampers the discovery of therapeutic strategies for improving the neurological phenotype due to CDKL5 mutations. Here, we show that the histone deacetylase 4 (HDAC4) is a direct phosphorylation target of CDKL5 and that CDKL5-dependent phosphorylation promotes HDAC4 cytoplasmic retention. Nuclear HDAC4 binds to chromatin as well as to MEF2A transcription factor, leading to histone deacetylation and altered neuronal gene expression. By using a Cdkl5 knockout (Cdkl5 -/Y) mouse model, we found that hypophosphorylated HDAC4 translocates to the nucleus of neural precursor cells, thereby reducing histone 3 acetylation. This effect was reverted by re-expression of CDKL5 or by inhibition of HDAC4 activity through the HDAC4 inhibitor LMK235. In Cdkl5 -/Y mice treated with LMK235, defective survival and maturation of neuronal precursor cells and hippocampus-dependent memory were fully normalized. These results demonstrate a critical role of HDAC4 in the neurodevelopmental alterations due to CDKL5 mutations and suggest the possibility of HDAC4-targeted pharmacological interventions.
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Affiliation(s)
- Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Claudia Fuchs
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Rocchina Viggiano
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | | | - Emanuele Valli
- Department of Pharmacy and Biotechnology, and CIRI Health Sciences and Technologies
| | - Paulina Jedynak
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Finn K Hansen
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität, Düsseldorf, Germany
| | - Giovanni Perini
- Department of Pharmacy and Biotechnology, and CIRI Health Sciences and Technologies
| | - Roberto Rimondini
- Department of Medical and Clinical Sciences, University of Bologna, Italy
| | - Thomas Kurz
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität, Düsseldorf, Germany
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
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Sivilia S, Mangano C, Beggiato S, Giuliani A, Torricella R, Baldassarro VA, Fernandez M, Lorenzini L, Giardino L, Borelli AC, Ferraro L, Calzà L. CDKL5 knockout leads to altered inhibitory transmission in the cerebellum of adult mice. GENES BRAIN AND BEHAVIOR 2016; 15:491-502. [DOI: 10.1111/gbb.12292] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 03/20/2016] [Accepted: 04/02/2016] [Indexed: 12/29/2022]
Affiliation(s)
- S. Sivilia
- Department of Veterinary Medical Science; University of Bologna; Bologna
| | - C. Mangano
- Department of Veterinary Medical Science; University of Bologna; Bologna
| | - S. Beggiato
- Department of Medical Sciences; University of Ferrara; Ferrara
| | - A. Giuliani
- Department of Veterinary Medical Science; University of Bologna; Bologna
| | - R. Torricella
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR); University of Bologna; Bologna
| | - V. A. Baldassarro
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR); University of Bologna; Bologna
| | - M. Fernandez
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR); University of Bologna; Bologna
| | - L. Lorenzini
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR); University of Bologna; Bologna
| | - L. Giardino
- Department of Veterinary Medical Science; University of Bologna; Bologna
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR); University of Bologna; Bologna
| | - A. C. Borelli
- Department of Medical Sciences; University of Ferrara; Ferrara
| | - L. Ferraro
- Department of Life Sciences and Biotechnology; University of Ferrara; Ferrara
| | - L. Calzà
- Department of Veterinary Medical Science; University of Bologna; Bologna
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR); University of Bologna; Bologna
- Department of Pharmacy and Biotechnology; University of Bologna; Bologna Italy
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CDKL5 and Shootin1 Interact and Concur in Regulating Neuronal Polarization. PLoS One 2016; 11:e0148634. [PMID: 26849555 PMCID: PMC4746202 DOI: 10.1371/journal.pone.0148634] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 01/21/2016] [Indexed: 12/26/2022] Open
Abstract
In the last years, the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene has been associated with epileptic encephalopathies characterized by the early onset of intractable epilepsy, severe developmental delay, autistic features, and often the development of Rett syndrome-like features. Still, the role of CDKL5 in neuronal functions is not fully understood. By way of a yeast two hybrid screening we identified the interaction of CDKL5 with shootin1, a brain specific protein acting as a determinant of axon formation during neuronal polarization. We found evidence that CDKL5 is involved, at least in part, in regulating neuronal polarization through its interaction with shootin1. Indeed, the two proteins interact in vivo and both are localized in the distal tip of outgrowing axons. By using primary hippocampal neurons as model system we find that adequate CDKL5 levels are required for axon specification. In fact, a significant number of neurons overexpressing CDKL5 is characterized by supernumerary axons, while the silencing of CDKL5 disrupts neuronal polarization. Interestingly, shootin1 phosphorylation is reduced in neurons silenced for CDKL5 suggesting that the kinase affects, directly or indirectly, the post-translational modification of shootin1. Finally, we find that the capacity of CDKL5 to generate surplus axons is attenuated in neurons with reduced shootin1 levels, in agreement with the notion that two proteins act in a common pathway. Altogether, these results point to a role of CDKL5 in the early steps of neuronal differentiation that can be explained, at least in part, by its association with shootin1.
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Isoflurane Is More Deleterious to Developing Brain Than Desflurane: The Role of the Akt/GSK3β Signaling Pathway. BIOMED RESEARCH INTERNATIONAL 2016; 2016:7919640. [PMID: 27057548 PMCID: PMC4753322 DOI: 10.1155/2016/7919640] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Revised: 12/09/2015] [Accepted: 12/14/2015] [Indexed: 02/07/2023]
Abstract
Demand is increasing for safer inhalational anesthetics for use in pediatric anesthesia. In this regard, researchers have debated whether isoflurane is more toxic to the developing brain than desflurane. In the present study, we compared the effects of postnatal exposure to isoflurane with those of desflurane on long-term cognitive performance and investigated the role of the Akt/GSK3β signaling pathway. Postnatal day 6 (P6) mice were exposed to either isoflurane or desflurane, after which the phosphorylation levels of Akt/GSK3β and learning and memory were assessed at P8 or P31. The phosphorylation levels of Akt/GSK3β and learning and memory were examined after intervention with lithium. We found that isoflurane, but not desflurane, impaired spatial learning and memory at P31. Accompanied by behavioral change, only isoflurane decreased p-Akt (ser473) and p-GSK3β (ser9) expressions, which led to GSK3β overactivation. Lithium prevented GSK3β overactivation and alleviated isoflurane-induced cognitive deficits. These results suggest that isoflurane is more likely to induce developmental neurotoxicity than desflurane in context of multiple exposures and that the Akt/GSK3β signaling pathway partly participates in this process. GSK3β inhibition might be an effective way to protect against developmental neurotoxicity.
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Yang JW, Ru J, Ma W, Gao Y, Liang Z, Liu J, Guo JH, Li LY. BDNF promotes the growth of human neurons through crosstalk with the Wnt/β-catenin signaling pathway via GSK-3β. Neuropeptides 2015; 54:35-46. [PMID: 26311646 DOI: 10.1016/j.npep.2015.08.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 07/30/2015] [Accepted: 08/12/2015] [Indexed: 12/30/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) plays an important role in neuronal growth; however, the downstream regulatory mechanisms remain unclear. In this study, we investigated whether BDNF exerts its neurotrophic effects through the Wnt/β-catenin signaling pathway in human embryonic spinal cord neurons in vitro. We found that neuronal growth (soma size and average neurite length) was increased by transfection with a BDNF overexpression plasmid. Western blotting and real-time quantitative PCR showed that expression of the BDNF pathway components TrkB, PI3K, Akt and PLC-γ was increased by BDNF overexpression. Furthermore, the Wnt signaling factors Wnt, Frizzled and Dsh and the downstream target β-catenin were upregulated, whereas GSK-3β was downregulated. In contrast, when BDNF signaling was downregulated with BDNF siRNA, the growth of neurons was decreased. Furthermore, BDNF signaling factors, Wnt pathway components and β-catenin were all downregulated, whereas GSK-3β was upregulated. This suggests that BDNF affects the growth of neurons in vitro through crosstalk with Wnt signaling, and that GSK-3β may be a critical factor linking these two pathways. To evaluate this possibility, we treated neurons with 6-bromoindirubin-3'-oxime (BIO), a small molecule GSK-3β inhibitor. BIO reduced the effects of BDNF upregulation/downregulation on soma size and average neurite length, and suppressed the impact of BDNF modulation on the Wnt signaling pathway. Taken together, our findings suggest that BDNF promotes the growth of neurons in vitro through crosstalk with the Wnt/β-catenin signaling pathway, and that this interaction may be mediated by GSK-3β.
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Affiliation(s)
- Jin-Wei Yang
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan 650500, China; Second Department of General Surgery, First People's Hospital of Yunnan Province, Kunming, Yunnan 650032, China.
| | - Jin Ru
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan 650500, China; Second Department of General Surgery, First People's Hospital of Yunnan Province, Kunming, Yunnan 650032, China.
| | - Wei Ma
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan 650500, China.
| | - Yan Gao
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan 650500, China; Department of Pathology, Children's Hospital of Kunming City, Kunming, Yunnan 650034, China.
| | - Zhang Liang
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan 650500, China.
| | - Jia Liu
- Second Department of General Surgery, First People's Hospital of Yunnan Province, Kunming, Yunnan 650032, China.
| | - Jian-Hui Guo
- Second Department of General Surgery, First People's Hospital of Yunnan Province, Kunming, Yunnan 650032, China.
| | - Li-Yan Li
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan 650500, China.
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Fuchs C, Rimondini R, Viggiano R, Trazzi S, De Franceschi M, Bartesaghi R, Ciani E. Inhibition of GSK3β rescues hippocampal development and learning in a mouse model of CDKL5 disorder. Neurobiol Dis 2015; 82:298-310. [PMID: 26143616 DOI: 10.1016/j.nbd.2015.06.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 06/10/2015] [Accepted: 06/24/2015] [Indexed: 12/24/2022] Open
Abstract
Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been identified in a rare neurodevelopmental disorder characterized by early-onset seizures, severe developmental delay, intellectual disability and Rett syndrome-like features. CDKL5 is highly expressed in the brain during early postnatal stages, suggesting its importance for brain maturation. Using a newly-generated Cdkl5 knockout (Cdkl5 -/Y) mouse, we recently found that loss of Cdkl5 impairs postnatal hippocampal development with a reduction in neuronal precursor survival and maturation. These defects were accompanied by increased activity of the glycogen synthase kinase 3β (GSK3β) a crucial inhibitory regulator of many neurodevelopmental processes. The goal of the current study was to establish whether inhibition of GSK3β corrects hippocampal developmental defects due to Cdkl5 loss. We found that treatment with the GSK3β inhibitor SB216763 restored neuronal precursor survival, dendritic maturation, connectivity and hippocampus-dependent learning and memory in the Cdkl5 -/Y mouse. Importantly, these effects were retained one month after treatment cessation. At present, there are no therapeutic strategies to improve the neurological defects of subjects with CDKL5 disorder. Current results point at GSK3β inhibitors as potential therapeutic tools for the improvement of abnormal brain development in CDKL5 disorder.
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Affiliation(s)
- Claudia Fuchs
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Piazza di Porta San Donato 2, 40126 Bologna, Italy
| | - Roberto Rimondini
- Department of Medical and Clinical Sciences, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Rocchina Viggiano
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Piazza di Porta San Donato 2, 40126 Bologna, Italy
| | - Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Piazza di Porta San Donato 2, 40126 Bologna, Italy
| | - Marianna De Franceschi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Piazza di Porta San Donato 2, 40126 Bologna, Italy
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Piazza di Porta San Donato 2, 40126 Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Piazza di Porta San Donato 2, 40126 Bologna, Italy.
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Mertz J, Tan H, Pagala V, Bai B, Chen PC, Li Y, Cho JH, Shaw T, Wang X, Peng J. Sequential Elution Interactome Analysis of the Mind Bomb 1 Ubiquitin Ligase Reveals a Novel Role in Dendritic Spine Outgrowth. Mol Cell Proteomics 2015; 14:1898-910. [PMID: 25931508 DOI: 10.1074/mcp.m114.045898] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Indexed: 11/06/2022] Open
Abstract
The mind bomb 1 (Mib1) ubiquitin ligase is essential for controlling metazoan development by Notch signaling and possibly the Wnt pathway. It is also expressed in postmitotic neurons and regulates neuronal morphogenesis and synaptic activity by mechanisms that are largely unknown. We sought to comprehensively characterize the Mib1 interactome and study its potential function in neuron development utilizing a novel sequential elution strategy for affinity purification, in which Mib1 binding proteins were eluted under different stringency and then quantified by the isobaric labeling method. The strategy identified the Mib1 interactome with both deep coverage and the ability to distinguish high-affinity partners from low-affinity partners. A total of 817 proteins were identified during the Mib1 affinity purification, including 56 high-affinity partners and 335 low-affinity partners, whereas the remaining 426 proteins are likely copurified contaminants or extremely weak binding proteins. The analysis detected all previously known Mib1-interacting proteins and revealed a large number of novel components involved in Notch and Wnt pathways, endocytosis and vesicle transport, the ubiquitin-proteasome system, cellular morphogenesis, and synaptic activities. Immunofluorescence studies further showed colocalization of Mib1 with five selected proteins: the Usp9x (FAM) deubiquitinating enzyme, alpha-, beta-, and delta-catenins, and CDKL5. Mutations of CDKL5 are associated with early infantile epileptic encephalopathy-2 (EIEE2), a severe form of mental retardation. We found that the expression of Mib1 down-regulated the protein level of CDKL5 by ubiquitination, and antagonized CDKL5 function during the formation of dendritic spines. Thus, the sequential elution strategy enables biochemical characterization of protein interactomes; and Mib1 analysis provides a comprehensive interactome for investigating its role in signaling networks and neuronal development.
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Affiliation(s)
- Joseph Mertz
- From the ‡Departments of Structural Biology and Developmental Neurobiology
| | | | | | - Bing Bai
- From the ‡Departments of Structural Biology and Developmental Neurobiology
| | - Ping-Chung Chen
- From the ‡Departments of Structural Biology and Developmental Neurobiology
| | - Yuxin Li
- From the ‡Departments of Structural Biology and Developmental Neurobiology
| | | | - Timothy Shaw
- §St. Jude Proteomics Facility, ¶Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | | | - Junmin Peng
- From the ‡Departments of Structural Biology and Developmental Neurobiology, §St. Jude Proteomics Facility,
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Okuda K, Tanaka T. [Towards elucidating the regulatory roles of CDKL5 in synaptic transmission]. Nihon Yakurigaku Zasshi 2015; 145:183-6. [PMID: 25864828 DOI: 10.1254/fpj.145.183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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