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Barbour AJ, Gourmaud S, Lancaster E, Li X, Stewart DA, Hoag KF, Irwin DJ, Talos DM, Jensen FE. Seizures exacerbate excitatory: inhibitory imbalance in Alzheimer's disease and 5XFAD mice. Brain 2024; 147:2169-2184. [PMID: 38662500 PMCID: PMC11146435 DOI: 10.1093/brain/awae126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 03/02/2024] [Accepted: 03/24/2024] [Indexed: 05/14/2024] Open
Abstract
Approximately 22% of Alzheimer's disease (AD) patients suffer from seizures, and the co-occurrence of seizures and epileptiform activity exacerbates AD pathology and related cognitive deficits, suggesting that seizures may be a targetable component of AD progression. Given that alterations in neuronal excitatory:inhibitory (E:I) balance occur in epilepsy, we hypothesized that decreased markers of inhibition relative to those of excitation would be present in AD patients. We similarly hypothesized that in 5XFAD mice, the E:I imbalance would progress from an early stage (prodromal) to later symptomatic stages and be further exacerbated by pentylenetetrazol (PTZ) kindling. Post-mortem AD temporal cortical tissues from patients with or without seizure history were examined for changes in several markers of E:I balance, including levels of the inhibitory GABAA receptor, the sodium potassium chloride cotransporter 1 (NKCC1) and potassium chloride cotransporter 2 (KCC2) and the excitatory NMDA and AMPA type glutamate receptors. We performed patch-clamp electrophysiological recordings from CA1 neurons in hippocampal slices and examined the same markers of E:I balance in prodromal 5XFAD mice. We next examined 5XFAD mice at chronic stages, after PTZ or control protocols, and in response to chronic mTORC1 inhibitor rapamycin, administered following kindled seizures, for markers of E:I balance. We found that AD patients with comorbid seizures had worsened cognitive and functional scores and decreased GABAA receptor subunit expression, as well as increased NKCC1/KCC2 ratios, indicative of depolarizing GABA responses. Patch clamp recordings of prodromal 5XFAD CA1 neurons showed increased intrinsic excitability, along with decreased GABAergic inhibitory transmission and altered glutamatergic neurotransmission, indicating that E:I imbalance may occur in early disease stages. Furthermore, seizure induction in prodromal 5XFAD mice led to later dysregulation of NKCC1/KCC2 and a reduction in GluA2 AMPA glutamate receptor subunit expression, indicative of depolarizing GABA receptors and calcium permeable AMPA receptors. Finally, we found that chronic treatment with the mTORC1 inhibitor, rapamycin, at doses we have previously shown to attenuate seizure-induced amyloid-β pathology and cognitive deficits, could also reverse elevations of the NKCC1/KCC2 ratio in these mice. Our data demonstrate novel mechanisms of interaction between AD and epilepsy and indicate that targeting E:I balance, potentially with US Food and Drug Administration-approved mTOR inhibitors, hold therapeutic promise for AD patients with a seizure history.
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Affiliation(s)
- Aaron J Barbour
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sarah Gourmaud
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Eunjoo Lancaster
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Xiaofan Li
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David A Stewart
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Duke University School of Medicine, Durham, NC 27708, USA
| | - Keegan F Hoag
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David J Irwin
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Penn Frontotemporal Degeneration Center, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Delia M Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Pan X, Caillon A, Fan S, Khan S, Tomatsu S, Pshezhetsky AV. Heterologous HSPC Transplantation Rescues Neuroinflammation and Ameliorates Peripheral Manifestations in the Mouse Model of Lysosomal Transmembrane Enzyme Deficiency, MPS IIIC. Cells 2024; 13:877. [PMID: 38786099 PMCID: PMC11120110 DOI: 10.3390/cells13100877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 05/13/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024] Open
Abstract
Mucopolysaccharidosis III type C (MPS IIIC) is an untreatable neuropathic lysosomal storage disease caused by a genetic deficiency of the lysosomal N-acetyltransferase, HGSNAT, catalyzing a transmembrane acetylation of heparan sulfate. HGSNAT is a transmembrane enzyme incapable of free diffusion between the cells or their cross-correction, which limits development of therapies based on enzyme replacement and gene correction. Since our previous work identified neuroinflammation as a hallmark of the CNS pathology in MPS IIIC, we tested whether it can be corrected by replacement of activated brain microglia with neuroprotective macrophages/microglia derived from a heterologous HSPC transplant. Eight-week-old MPS IIIC (HgsnatP304L) mice were transplanted with HSPC from congenic wild type mice after myeloablation with Busulfan and studied using behavior test battery, starting from the age of 6 months. At the age of ~8 months, mice were sacrificed to study pathological changes in the brain, heparan sulfate storage, and other biomarkers of the disease. We found that the treatment corrected several behavior deficits including hyperactivity and reduction in socialization, but not memory decline. It also improved several features of CNS pathology such as microastroglyosis, expression of pro-inflammatory cytokine IL-1β, and accumulation of misfolded amyloid aggregates in cortical neurons. At the periphery, the treatment delayed development of terminal urinary retention, potentially increasing longevity, and reduced blood levels of heparan sulfate. However, we did not observe correction of lysosomal storage phenotype in neurons and heparan sulfate brain levels. Together, our results demonstrate that neuroinflammation in a neurological lysosomal storage disease, caused by defects in a transmembrane enzyme, can be effectively ameliorated by replacement of microglia bearing the genetic defect with cells from a normal healthy donor. They also suggest that heterologous HSPC transplant, if used together with other methods, such as chaperone therapy or substrate reduction therapy, may constitute an effective combination therapy for MPS IIIC and other disorders with a similar etiology.
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Affiliation(s)
- Xuefang Pan
- Department of Pediatrics and Centre Hospitalier Universitaire Sainte-Justine Research Centre, University of Montreal, Montreal, QC H3T 1C5, Canada; (X.P.); (A.C.); (S.F.)
| | - Antoine Caillon
- Department of Pediatrics and Centre Hospitalier Universitaire Sainte-Justine Research Centre, University of Montreal, Montreal, QC H3T 1C5, Canada; (X.P.); (A.C.); (S.F.)
| | - Shuxian Fan
- Department of Pediatrics and Centre Hospitalier Universitaire Sainte-Justine Research Centre, University of Montreal, Montreal, QC H3T 1C5, Canada; (X.P.); (A.C.); (S.F.)
- Department of Anatomy and Cell Biology, McGill University, Montreal, QC H3A 0C7, Canada
| | - Shaukat Khan
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; (S.K.); (S.T.)
| | - Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; (S.K.); (S.T.)
| | - Alexey V. Pshezhetsky
- Department of Pediatrics and Centre Hospitalier Universitaire Sainte-Justine Research Centre, University of Montreal, Montreal, QC H3T 1C5, Canada; (X.P.); (A.C.); (S.F.)
- Department of Anatomy and Cell Biology, McGill University, Montreal, QC H3A 0C7, Canada
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Sgro M, Kodila ZN, Li C, Carmichael I, Warren S, Reichelt AC, Yamakawa GR, Mychasiuk R. Microbiome depletion prior to repeat mild TBI differentially alters social deficits and prefrontal cortex plasticity in adolescent and adult rats. iScience 2024; 27:109395. [PMID: 38510122 PMCID: PMC10952042 DOI: 10.1016/j.isci.2024.109395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/21/2023] [Accepted: 02/28/2024] [Indexed: 03/22/2024] Open
Abstract
Although aging, repeat mild traumatic brain injury (RmTBI), and microbiome modifications independently change social behavior, there has been no investigation into their cumulative effects on social behavior and neuroplasticity within the prefrontal cortex. Therefore, we examined how microbiome depletion prior to RmTBI affected social behavior and neuroplasticity in adolescent and adult rats. Play, temperament analysis, elevated plus maze, and the hot/cold plate assessed socio-emotional function. Analyses of perineuronal nets (PNNs) and parvalbumin (PV) interneurons was completed. Social-emotional deficits were more pronounced in adults, with microbiome depletion attenuating social behavior deficits associated with RmTBI in both age groups. Microbiome depletion increased branch length and PNN arborization within the PFC but decreased the overall number of PNNs. Adults and males were more vulnerable to RmTBI. Interestingly, microbiome depletion may have attenuated the changes to neuroplasticity and subsequent social deficits, suggesting that the microbiome is a viable, but age-specific, target for RmTBI therapeutics.
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Affiliation(s)
- Marissa Sgro
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Zoe N. Kodila
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Crystal Li
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Irena Carmichael
- Monash Micro Imaging, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Samantha Warren
- Monash Micro Imaging, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Amy C. Reichelt
- School of Biomedicine, University of Adelaide, Adelaide, SA 5005, Australia
| | - Glenn R. Yamakawa
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Richelle Mychasiuk
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
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Campbell BFN, Cruz-Ochoa N, Otomo K, Lukacsovich D, Espinosa P, Abegg A, Luo W, Bellone C, Földy C, Tyagarajan SK. Gephyrin phosphorylation facilitates sexually dimorphic development and function of parvalbumin interneurons in the mouse hippocampus. Mol Psychiatry 2024:10.1038/s41380-024-02517-5. [PMID: 38503929 DOI: 10.1038/s41380-024-02517-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 02/25/2024] [Accepted: 03/04/2024] [Indexed: 03/21/2024]
Abstract
The precise function of specialized GABAergic interneuron subtypes is required to provide appropriate synaptic inhibition for regulating principal neuron excitability and synchronization within brain circuits. Of these, parvalbumin-type (PV neuron) dysfunction is a feature of several sex-biased psychiatric and brain disorders, although, the underlying developmental mechanisms are unclear. While the transcriptional action of sex hormones generates sexual dimorphism during brain development, whether kinase signaling contributes to sex differences in PV neuron function remains unexplored. In the hippocampus, we report that gephyrin, the main inhibitory post-synaptic scaffolding protein, is phosphorylated at serine S268 and S270 in a developmentally-dependent manner in both males and females. When examining GphnS268A/S270A mice in which site-specific phosphorylation is constitutively blocked, we found that sex differences in PV neuron density in the hippocampal CA1 present in WT mice were abolished, coincident with a female-specific increase in PV neuron-derived terminals and increased inhibitory input onto principal cells. Electrophysiological analysis of CA1 PV neurons indicated that gephyrin phosphorylation is required for sexually dimorphic function. Moreover, while male and female WT mice showed no difference in hippocampus-dependent memory tasks, GphnS268A/S270A mice exhibited sex- and task-specific deficits, indicating that gephyrin phosphorylation is differentially required by males and females for convergent cognitive function. In fate mapping experiments, we uncovered that gephyrin phosphorylation at S268 and S270 establishes sex differences in putative PV neuron density during early postnatal development. Furthermore, patch-sequencing of putative PV neurons at postnatal day 4 revealed that gephyrin phosphorylation contributes to sex differences in the transcriptomic profile of developing interneurons. Therefore, these early shifts in male-female interneuron development may drive adult sex differences in PV neuron function and connectivity. Our results identify gephyrin phosphorylation as a new substrate organizing PV neuron development at the anatomical, functional, and transcriptional levels in a sex-dependent manner, thus implicating kinase signaling disruption as a new mechanism contributing to the sex-dependent etiology of brain disorders.
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Affiliation(s)
- Benjamin F N Campbell
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland
| | - Natalia Cruz-Ochoa
- Laboratory of Neural Connectivity, Brain Research Institute, Faculties of Medicine and Science, University of Zürich, 8057, Zürich, Switzerland
- Adaptive Brain Circuits in Development and Learning (AdaBD), University Research Priority Program (URPP), University of Zürich, 8057, Zürich, Switzerland
| | - Kanako Otomo
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland
| | - David Lukacsovich
- Laboratory of Neural Connectivity, Brain Research Institute, Faculties of Medicine and Science, University of Zürich, 8057, Zürich, Switzerland
| | - Pedro Espinosa
- Department of Basic Neuroscience, University of Geneva, 1211, Geneva, Switzerland
| | - Andrin Abegg
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland
| | - Wenshu Luo
- Laboratory of Neural Connectivity, Brain Research Institute, Faculties of Medicine and Science, University of Zürich, 8057, Zürich, Switzerland
| | - Camilla Bellone
- Department of Basic Neuroscience, University of Geneva, 1211, Geneva, Switzerland
| | - Csaba Földy
- Laboratory of Neural Connectivity, Brain Research Institute, Faculties of Medicine and Science, University of Zürich, 8057, Zürich, Switzerland
- Adaptive Brain Circuits in Development and Learning (AdaBD), University Research Priority Program (URPP), University of Zürich, 8057, Zürich, Switzerland
| | - Shiva K Tyagarajan
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland.
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Liénard C, Pintart A, Bomont P. Neuronal Autophagy: Regulations and Implications in Health and Disease. Cells 2024; 13:103. [PMID: 38201307 PMCID: PMC10778363 DOI: 10.3390/cells13010103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 12/02/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024] Open
Abstract
Autophagy is a major degradative pathway that plays a key role in sustaining cell homeostasis, integrity, and physiological functions. Macroautophagy, which ensures the clearance of cytoplasmic components engulfed in a double-membrane autophagosome that fuses with lysosomes, is orchestrated by a complex cascade of events. Autophagy has a particularly strong impact on the nervous system, and mutations in core components cause numerous neurological diseases. We first review the regulation of autophagy, from autophagosome biogenesis to lysosomal degradation and associated neurodevelopmental/neurodegenerative disorders. We then describe how this process is specifically regulated in the axon and in the somatodendritic compartment and how it is altered in diseases. In particular, we present the neuronal specificities of autophagy, with the spatial control of autophagosome biogenesis, the close relationship of maturation with axonal transport, and the regulation by synaptic activity. Finally, we discuss the physiological functions of autophagy in the nervous system, during development and in adulthood.
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Affiliation(s)
- Caroline Liénard
- NeuroMyoGene Institute—PGNM, CNRS UMR 5261—INSERM U1315, University of Claude Bernard Lyon 1, 69008 Lyon, France; (C.L.); (A.P.)
- CHU Montpellier, University of Montpellier, 34295 Montpellier, France
| | - Alexandre Pintart
- NeuroMyoGene Institute—PGNM, CNRS UMR 5261—INSERM U1315, University of Claude Bernard Lyon 1, 69008 Lyon, France; (C.L.); (A.P.)
| | - Pascale Bomont
- NeuroMyoGene Institute—PGNM, CNRS UMR 5261—INSERM U1315, University of Claude Bernard Lyon 1, 69008 Lyon, France; (C.L.); (A.P.)
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Curatolo P, Scheper M, Emberti Gialloreti L, Specchio N, Aronica E. Is tuberous sclerosis complex-associated autism a preventable and treatable disorder? World J Pediatr 2024; 20:40-53. [PMID: 37878130 DOI: 10.1007/s12519-023-00762-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 09/10/2023] [Indexed: 10/26/2023]
Abstract
BACKGROUND Tuberous sclerosis complex (TSC) is a genetic disorder caused by inactivating mutations in the TSC1 and TSC2 genes, causing overactivation of the mechanistic (previously referred to as mammalian) target of rapamycin (mTOR) signaling pathway in fetal life. The mTOR pathway plays a crucial role in several brain processes leading to TSC-related epilepsy, intellectual disability, and autism spectrum disorder (ASD). Pre-natal or early post-natal diagnosis of TSC is now possible in a growing number of pre-symptomatic infants. DATA SOURCES We searched PubMed for peer-reviewed publications published between January 2010 and April 2023 with the terms "tuberous sclerosis", "autism", or "autism spectrum disorder"," animal models", "preclinical studies", "neurobiology", and "treatment". RESULTS Prospective studies have highlighted that developmental trajectories in TSC infants who were later diagnosed with ASD already show motor, visual and social communication skills in the first year of life delays. Reliable genetic, cellular, electroencephalography and magnetic resonance imaging biomarkers can identify pre-symptomatic TSC infants at high risk for having autism and epilepsy. CONCLUSIONS Preventing epilepsy or improving therapy for seizures associated with prompt and tailored treatment strategies for autism in a sensitive developmental time window could have the potential to mitigate autistic symptoms in infants with TSC.
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Affiliation(s)
- Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
| | - Mirte Scheper
- Department of Neuropathology, Amsterdam Neuroscience, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
| | - Leonardo Emberti Gialloreti
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Via Montpellier 1, 00133, Rome, Italy
| | - Nicola Specchio
- Clinical and Experimental Neurology, Bambino Gesù Children's Hospital, IRCCS, Full Member of European Reference Network EpiCARE, Piazza S. Onofrio 4, 00165, Rome, Italy.
| | - Eleonora Aronica
- Department of Neuropathology, Amsterdam Neuroscience, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Amsterdam, The Netherlands
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Gonda S, Riedel C, Reiner A, Köhler I, Wahle P. Axons of cortical basket cells originating from dendrites develop higher local complexity than axons emerging from basket cell somata. Development 2023; 150:dev202305. [PMID: 37902086 PMCID: PMC10690106 DOI: 10.1242/dev.202305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 10/24/2023] [Indexed: 10/31/2023]
Abstract
Neuronal differentiation is regulated by neuronal activity. Here, we analyzed dendritic and axonal growth of Basket cells (BCs) and non-Basket cells (non-BCs) using sparse transfection of channelrhodopsin-YFP and repetitive optogenetic stimulation in slice cultures of rat visual cortex. Neocortical interneurons often display axon-carrying dendrites (AcDs). We found that the AcDs of BCs and non-BCs were, on average, the most complex dendrites. Further, the AcD configuration had an influence on BC axonal development. Axons originating from an AcD formed denser arborizations with more terminal endings within the dendritic field of the parent cell. Intriguingly, this occurred already in unstimulated BCs, and complexity was not increased further by optogenetic stimulation. However, optogenetic stimulation exerted a growth-promoting effect on axons emerging from BC somata. The axons of non-BCs neither responded to the AcD configuration nor to the optogenetic stimulation. The results suggest that the formation of locally dense BC plexuses is regulated by spontaneous activity. Moreover, in the AcD configuration, the AcD and the axon it carries mutually support each other's growth.
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Affiliation(s)
- Steffen Gonda
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801 Bochum, Germany
| | - Christian Riedel
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801 Bochum, Germany
| | - Andreas Reiner
- Cellular Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801 Bochum, Germany
| | - Ina Köhler
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801 Bochum, Germany
| | - Petra Wahle
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801 Bochum, Germany
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Specchio N, Nabbout R, Aronica E, Auvin S, Benvenuto A, de Palma L, Feucht M, Jansen F, Kotulska K, Sarnat H, Lagae L, Jozwiak S, Curatolo P. Updated clinical recommendations for the management of tuberous sclerosis complex associated epilepsy. Eur J Paediatr Neurol 2023; 47:25-34. [PMID: 37669572 DOI: 10.1016/j.ejpn.2023.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 08/27/2023] [Accepted: 08/28/2023] [Indexed: 09/07/2023]
Abstract
Children with tuberous sclerosis complex (TSC), may experience a variety of seizure types in the first year of life, most often focal seizure sand epileptic spasms. Drug resistance is seen early in many patients, and the management of TSC associated epilepsy remain a major challenge for clinicians. In 2018 clinical recommendations for the management of TSC associated epilepsy were published by a panel of European experts. In the last five years considerable progress has been made in understanding the neurobiology of epileptogenesis and three interventional randomized controlled trials have changed the therapeutic approach for the management of TSC associated epilepsy. Pre-symptomatic treatment with vigabatrin may delay seizure onset, may reduce seizure severity and reduce the risk of epileptic encephalopathy. The efficacy of mTOR inhibition with adjunctive everolimus was documented in patients with TSC associated refractory seizures and cannabidiol could be another therapeutic option. Epilepsy surgery has significantly improved seizure outcome in selected patients and should be considered early in all patients with drug resistant epilepsy. There is a need to identify patients who may have a higher risk of developing epilepsy and autism spectrum disorder (ASD). In the recent years significant progress has been made owing to the early identification of risk factors for the development of drug-resistant epilepsy. Better understanding of the mechanism underlying epileptogenesis may improve the management for TSC-related epilepsy. Developmental neurobiology and neuropathology give opportunities for the implementation of concepts related to clinical findings, and an early genetic diagnosis and use of EEG and MRI biomarkers may improve the development of pre-symptomatic and disease-modifying strategies.
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Affiliation(s)
- Nicola Specchio
- Clinical and Experimental Neurology, Bambino Gesu' Children's Hospital IRCCS, Full Member of European Reference Network on Rare and Complex Epilepsies EpiCARE, Rome, Italy.
| | - Rima Nabbout
- Department of Pediatric Neurology, Necker Enfants Malades Hospital, Université Paris Cité, Member of the European Reference Network on Rare and Complex Epilepsies EpiCARE, INSERM U1163, Institut Imagine, Paris, France
| | - Eleonora Aronica
- Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Department of (Neuro)Pathology, Amsterdam, Netherlands; Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, the Netherlands
| | - Stephane Auvin
- APHP, Service de Neurologie Pédiatrique, Centre Epilepsies Rares, Member of the European Reference Network on Rare and Complex Epilepsies EpiCARE, Hôpital Robert Debré, Paris, France; Université Paris-Cité, INSERM NeuroDiderot, Paris, France; Institut Universitaire de France (IUF), Paris, France
| | | | - Luca de Palma
- Clinical and Experimental Neurology, Bambino Gesu' Children's Hospital IRCCS, Full Member of European Reference Network on Rare and Complex Epilepsies EpiCARE, Rome, Italy
| | - Martha Feucht
- Epilepsy Center, Department of Pediatrics, Medical University Vienna, Austria
| | - Floor Jansen
- Department of Pediatric Neurology, Brain Center UMC Utrecht, the Netherlands
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland
| | - Harvey Sarnat
- Department of Paediatrics (Neurology), Pathology and Laboratory Medicine (Neuropathology) and Clinical Neurosciences, University of Calgary Cumming School of Medicine and Alberta Children's Hospital Research Institute (Owerko Centre), Calgary, AB, Canada
| | - Lieven Lagae
- Department of Paediatric Neurology, University of Leuven, Leuven, Belgium
| | - Sergiusz Jozwiak
- Research Department, The Children's Memorial Health Institute, ERN EPICARE, Warsaw, Poland
| | - Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
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Zhang Y, Guo Z, Yang L, Cheng C, Gai C, Gao Y, Zhang Y, Sun H, Hu D. Possible Involvement of Perineuronal Nets in Anti-Depressant Effects of Electroacupuncture in Chronic-Stress-Induced Depression in Rats. Neurochem Res 2023; 48:3146-3159. [PMID: 37347359 DOI: 10.1007/s11064-023-03970-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 05/29/2023] [Accepted: 06/12/2023] [Indexed: 06/23/2023]
Abstract
Acupuncture can alleviate depression-like behaviors. However, the neural mechanisms behind the anti-depressive effect remain unknown. Perineuronal net (PNN) abnormalities have been reported in multiple psychiatric disorders. This study investigated the modulation and neural mechanism of PNNs in the anti-depressant process of electroacupuncture (EA) at Baihui (GV20) and Yintang (GV29) points. A rat depression model was induced by chronic unpredicted mild stress (CUMS). The results revealed that CUMS, applied for four weeks, specifically reduces PNNs around parvalbumin (PV). In addition, EA and fluoxetine treatments reverse the decrease in PNNs+ cell density and the ratio of PV and PNN double-positive cells to PV+ neurons in the medial prefrontal cortex (mPFC) after CUMS. Furthermore, EA treatment can reverse the decrease in the protein expression of PNN components (aggrecan and brevican) in the mPFC caused by stress. After EA treatment, the decreased expression of GAD67, GLuA1, and PSD95 in the mPFC induced by CUMS for four weeks was also reversed. PNN degradation in mPFC brain areas potentially interferes with the anti-depressant benefits of EA in rats with depression induced by CUMS. EA treatment did not increase PNNs+ cell density and the ratio of PV and PNN double-positive cells to PV+ neurons after PNNs degradation in the mPFC brain region of rats. This finding indicated that the mechanism of acupuncture's anti-depressant effect may be based on reversing the CUMS-induced decline in PNN expression, the functional impairment of γ-aminobutyric acid (GABA) neurons, and the regulation of excitatory synaptic proteins expression.
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Affiliation(s)
- Yuxin Zhang
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
- Institute of Metabolic Diseases, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Zhenyu Guo
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Luping Yang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China
| | - Cuicui Cheng
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Cong Gai
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Yushan Gao
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Yi Zhang
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Hongmei Sun
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Die Hu
- Department of Anatomy, School of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.
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Toudji I, Toumi A, Chamberland É, Rossignol E. Interneuron odyssey: molecular mechanisms of tangential migration. Front Neural Circuits 2023; 17:1256455. [PMID: 37779671 PMCID: PMC10538647 DOI: 10.3389/fncir.2023.1256455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 08/21/2023] [Indexed: 10/03/2023] Open
Abstract
Cortical GABAergic interneurons are critical components of neural networks. They provide local and long-range inhibition and help coordinate network activities involved in various brain functions, including signal processing, learning, memory and adaptative responses. Disruption of cortical GABAergic interneuron migration thus induces profound deficits in neural network organization and function, and results in a variety of neurodevelopmental and neuropsychiatric disorders including epilepsy, intellectual disability, autism spectrum disorders and schizophrenia. It is thus of paramount importance to elucidate the specific mechanisms that govern the migration of interneurons to clarify some of the underlying disease mechanisms. GABAergic interneurons destined to populate the cortex arise from multipotent ventral progenitor cells located in the ganglionic eminences and pre-optic area. Post-mitotic interneurons exit their place of origin in the ventral forebrain and migrate dorsally using defined migratory streams to reach the cortical plate, which they enter through radial migration before dispersing to settle in their final laminar allocation. While migrating, cortical interneurons constantly change their morphology through the dynamic remodeling of actomyosin and microtubule cytoskeleton as they detect and integrate extracellular guidance cues generated by neuronal and non-neuronal sources distributed along their migratory routes. These processes ensure proper distribution of GABAergic interneurons across cortical areas and lamina, supporting the development of adequate network connectivity and brain function. This short review summarizes current knowledge on the cellular and molecular mechanisms controlling cortical GABAergic interneuron migration, with a focus on tangential migration, and addresses potential avenues for cell-based interneuron progenitor transplants in the treatment of neurodevelopmental disorders and epilepsy.
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Affiliation(s)
- Ikram Toudji
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Montréal, QC, Canada
- Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
| | - Asmaa Toumi
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Montréal, QC, Canada
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, QC, Canada
| | - Émile Chamberland
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Montréal, QC, Canada
- Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
| | - Elsa Rossignol
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Montréal, QC, Canada
- Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
- Department of Pediatrics, Université de Montréal, Montréal, QC, Canada
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11
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Matthiesen M, Khlaifia A, Steininger CFD, Dadabhoy M, Mumtaz U, Arruda-Carvalho M. Maturation of nucleus accumbens synaptic transmission signals a critical period for the rescue of social deficits in a mouse model of autism spectrum disorder. Mol Brain 2023; 16:46. [PMID: 37226266 DOI: 10.1186/s13041-023-01028-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 04/20/2023] [Indexed: 05/26/2023] Open
Abstract
Social behavior emerges early in development, a time marked by the onset of neurodevelopmental disorders featuring social deficits, including autism spectrum disorder (ASD). Although social deficits are at the core of the clinical diagnosis of ASD, very little is known about their neural correlates at the time of clinical onset. The nucleus accumbens (NAc), a brain region extensively implicated in social behavior, undergoes synaptic, cellular and molecular alterations in early life, and is particularly affected in ASD mouse models. To explore a link between the maturation of the NAc and neurodevelopmental deficits in social behavior, we compared spontaneous synaptic transmission in NAc shell medium spiny neurons (MSNs) between the highly social C57BL/6J and the idiopathic ASD mouse model BTBR T+Itpr3tf/J at postnatal day (P) 4, P6, P8, P12, P15, P21 and P30. BTBR NAc MSNs display increased spontaneous excitatory transmission during the first postnatal week, and increased inhibition across the first, second and fourth postnatal weeks, suggesting accelerated maturation of excitatory and inhibitory synaptic inputs compared to C57BL/6J mice. BTBR mice also show increased optically evoked medial prefrontal cortex-NAc paired pulse ratios at P15 and P30. These early changes in synaptic transmission are consistent with a potential critical period, which could maximize the efficacy of rescue interventions. To test this, we treated BTBR mice in either early life (P4-P8) or adulthood (P60-P64) with the mTORC1 antagonist rapamycin, a well-established intervention for ASD-like behavior. Rapamycin treatment rescued social interaction deficits in BTBR mice when injected in infancy, but did not affect social interaction in adulthood.
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Affiliation(s)
- Melina Matthiesen
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
| | - Abdessattar Khlaifia
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
| | | | - Maryam Dadabhoy
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
| | - Unza Mumtaz
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
| | - Maithe Arruda-Carvalho
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada.
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S3G5, Canada.
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12
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Chehrazi P, Lee KKY, Lavertu-Jolin M, Abbasnejad Z, Carreño-Muñoz MI, Chattopadhyaya B, Di Cristo G. p75 neurotrophin receptor in pre-adolescent prefrontal PV interneurons promotes cognitive flexibility in adult mice. Biol Psychiatry 2023:S0006-3223(23)01238-6. [PMID: 37120061 DOI: 10.1016/j.biopsych.2023.04.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/31/2023] [Accepted: 04/16/2023] [Indexed: 05/01/2023]
Abstract
BACKGROUND Parvalbumin (PV)-positive GABAergic cells provide robust perisomatic inhibition to neighboring pyramidal neurons and regulate brain oscillations. Alterations in PV interneuron connectivity and function in the medial prefrontal cortex (mPFC) have been consistently reported in psychiatric disorders associated with cognitive rigidity, suggesting that PV cell deficits could be a core cellular phenotype in these disorders. p75 neurotrophin receptor (p75NTR) regulates the time course of PV cell maturation in a cell-autonomous fashion. Whether p75NTR expression during postnatal development affects adult prefrontal PV cell connectivity and cognitive function is unknown. METHODS We generated transgenic mice with conditional knockout (cKO) of p75NTR in postnatal PV cells. We analysed PV cell connectivity and recruitment following a tail pinch, by immunolabeling and confocal imaging, in naïve mice or following p75NTR re-expression in pre- or post-adolescent mice using Cre-dependent viral vectors. Cognitive flexibility was evaluated using behavioral tests. RESULTS PV cell-specific p75NTR deletion increased both PV cell synapse density and the proportion of PV cells surrounded by perineuronal nets, a marker of mature PV cells, in adult mPFC but not visual cortex. Both phenotypes were rescued by viral-mediated re-introduction of p75NTR in pre-adolescent but not post-adolescent mPFC. Prefrontal cortical PV cells failed to upregulate c-Fos following a tail-pinch stimulation in adult cKO mice. Finally, cKO mice showed impaired fear memory extinction learning as well as deficits in a attention set-shifting task. CONCLUSION These findings suggest that p75NTR expression in adolescent PV cells contributes to the fine tuning of their connectivity and promotes cognitive flexibility in adulthood.
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Affiliation(s)
- Pegah Chehrazi
- Centre de Recherche, CHU Sainte-Justine (CHUSJ), Montréal, Canada; Department of Neurosciences, Université de Montréal, Montréal, Canada
| | - Karen Ka Yan Lee
- Centre de Recherche, CHU Sainte-Justine (CHUSJ), Montréal, Canada; Department of Neurosciences, Université de Montréal, Montréal, Canada
| | - Marisol Lavertu-Jolin
- Centre de Recherche, CHU Sainte-Justine (CHUSJ), Montréal, Canada; Department of Neurosciences, Université de Montréal, Montréal, Canada
| | - Zahra Abbasnejad
- Centre de Recherche, CHU Sainte-Justine (CHUSJ), Montréal, Canada; Department of Neurosciences, Université de Montréal, Montréal, Canada
| | - Maria Isabel Carreño-Muñoz
- Centre de Recherche, CHU Sainte-Justine (CHUSJ), Montréal, Canada; Department of Neurosciences, Université de Montréal, Montréal, Canada
| | | | - Graziella Di Cristo
- Centre de Recherche, CHU Sainte-Justine (CHUSJ), Montréal, Canada; Department of Neurosciences, Université de Montréal, Montréal, Canada.
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13
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Wang J, Wang Z, Dai L, Zhu X, Guan X, Wang J, Li J, Zhang M, Bai Y, Guo H. Supt16 Haploinsufficiency Impairs PI3K/AKT/mTOR/Autophagy Pathway in Human Pluripotent Stem Cells Derived Neural Stem Cells. Int J Mol Sci 2023; 24:ijms24033035. [PMID: 36769360 PMCID: PMC9917370 DOI: 10.3390/ijms24033035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/29/2023] [Accepted: 01/31/2023] [Indexed: 02/08/2023] Open
Abstract
The maintenance of neural stem cells (NSCs) plays a critical role in neurodevelopment and has been implicated in neurodevelopmental disorders (NDDs). However, the underlying mechanisms linking defective human neural stem cell self-renewal to NDDs remain undetermined. Our previous study found that Supt16 haploinsufficiency causes cognitive and social behavior deficits by disrupting the stemness maintenance of NSCs in mice. However, its effects and underlying mechanisms have not been elucidated in human neural stem cells (hNSCs). Here, we generated Supt16+/- induced pluripotent stem cells (iPSCs) and induced them into hNSCs. The results revealed that Supt16 heterozygous hNSCs exhibit impaired proliferation, cell cycle arrest, and increased apoptosis. As the RNA-seq analysis showed, Supt16 haploinsufficiency inhibited the PI3K/AKT/mTOR pathway, leading to rising autophagy, and further resulted in the dysregulated expression of multiple proteins related to cell proliferation and apoptotic process. Furthermore, the suppression of Supt16 heterozygous hNSC self-renewal caused by autophagy activation could be rescued by MHY1485 treatment or reproduced in rapamycin-treated hNSCs. Thus, our results showed that Supt16 was essential for hNSC self-renewal and its haploinsufficiency led to cell cycle arrest, impaired cell proliferation, and increased apoptosis of hNSCs by regulating the PI3K/AKT/mTOR/autophagy pathway. These provided a new insight to understand the causality between the Supt16 heterozygous NSCs and NDDs in humans.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Yun Bai
- Correspondence: (Y.B.); (H.G.); Tel./Fax: +86-23-68771367 (H.G.)
| | - Hong Guo
- Correspondence: (Y.B.); (H.G.); Tel./Fax: +86-23-68771367 (H.G.)
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14
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FDA-Approved Kinase Inhibitors in Preclinical and Clinical Trials for Neurological Disorders. Pharmaceuticals (Basel) 2022; 15:ph15121546. [PMID: 36558997 PMCID: PMC9784968 DOI: 10.3390/ph15121546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/09/2022] [Accepted: 12/09/2022] [Indexed: 12/14/2022] Open
Abstract
Cancers and neurological disorders are two major types of diseases. We previously developed a new concept termed "Aberrant Cell Cycle Diseases" (ACCD), revealing that these two diseases share a common mechanism of aberrant cell cycle re-entry. The aberrant cell cycle re-entry is manifested as kinase/oncogene activation and tumor suppressor inactivation, which are hallmarks of both tumor growth in cancers and neuronal death in neurological disorders. Therefore, some cancer therapies (e.g., kinase inhibition, tumor suppressor elevation) can be leveraged for neurological treatments. The United States Food and Drug Administration (US FDA) has so far approved 74 kinase inhibitors, with numerous other kinase inhibitors in clinical trials, mostly for the treatment of cancers. In contrast, there are dire unmet needs of FDA-approved drugs for neurological treatments, such as Alzheimer's disease (AD), intracerebral hemorrhage (ICH), ischemic stroke (IS), traumatic brain injury (TBI), and others. In this review, we list these 74 FDA-approved kinase-targeted drugs and identify those that have been reported in preclinical and/or clinical trials for neurological disorders, with a purpose of discussing the feasibility and applicability of leveraging these cancer drugs (FDA-approved kinase inhibitors) for neurological treatments.
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15
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Royero P, Quatraccioni A, Früngel R, Silva MH, Bast A, Ulas T, Beyer M, Opitz T, Schultze JL, Graham ME, Oberlaender M, Becker A, Schoch S, Beck H. Circuit-selective cell-autonomous regulation of inhibition in pyramidal neurons by Ste20-like kinase. Cell Rep 2022; 41:111757. [PMID: 36476865 PMCID: PMC9756112 DOI: 10.1016/j.celrep.2022.111757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 10/18/2022] [Accepted: 11/09/2022] [Indexed: 12/12/2022] Open
Abstract
Maintaining an appropriate balance between excitation and inhibition is critical for neuronal information processing. Cortical neurons can cell-autonomously adjust the inhibition they receive to individual levels of excitatory input, but the underlying mechanisms are unclear. We describe that Ste20-like kinase (SLK) mediates cell-autonomous regulation of excitation-inhibition balance in the thalamocortical feedforward circuit, but not in the feedback circuit. This effect is due to regulation of inhibition originating from parvalbumin-expressing interneurons, while inhibition via somatostatin-expressing interneurons is unaffected. Computational modeling shows that this mechanism promotes stable excitatory-inhibitory ratios across pyramidal cells and ensures robust and sparse coding. Patch-clamp RNA sequencing yields genes differentially regulated by SLK knockdown, as well as genes associated with excitation-inhibition balance participating in transsynaptic communication and cytoskeletal dynamics. These data identify a mechanism for cell-autonomous regulation of a specific inhibitory circuit that is critical to ensure that a majority of cortical pyramidal cells participate in information coding.
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Affiliation(s)
- Pedro Royero
- Institute of Experimental Epileptology and Cognition Research, University of Bonn, University of Bonn Medical Center, Venusberg-Campus 1, 53105 Bonn, Germany,International Max Planck Research School for Brain and Behavior, Bonn, Germany
| | - Anne Quatraccioni
- Department of Neuropathology, University Hospital Bonn, Section for Translational Epilepsy Research, 53127 Bonn, Germany,International Max Planck Research School for Brain and Behavior, Bonn, Germany
| | - Rieke Früngel
- In Silico Brain Sciences Group, Max-Planck Institute for Neurobiology of Behavior – Caesar, Bonn, Germany,International Max Planck Research School for Brain and Behavior, Bonn, Germany
| | - Mariella Hurtado Silva
- Synapse Proteomics, Children’s Medical Research Institute, The University of Sydney, Sydney, NSW, Australia
| | - Arco Bast
- In Silico Brain Sciences Group, Max-Planck Institute for Neurobiology of Behavior – Caesar, Bonn, Germany,International Max Planck Research School for Brain and Behavior, Bonn, Germany
| | - Thomas Ulas
- Systems Medicine, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) e.V., Bonn, Germany,PRECISE Platform for Single Cell Genomics and Epigenomics, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) e.V. and University of Bonn, Bonn, Germany,Genomics & Immunoregulation, LIMES Institute, University of Bonn, Bonn, Germany
| | - Marc Beyer
- PRECISE Platform for Single Cell Genomics and Epigenomics, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) e.V. and University of Bonn, Bonn, Germany,Immunogenomics & Neurodegeneration, Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Bonn, Germany
| | - Thoralf Opitz
- Institute of Experimental Epileptology and Cognition Research, University of Bonn, University of Bonn Medical Center, Venusberg-Campus 1, 53105 Bonn, Germany
| | - Joachim L. Schultze
- Systems Medicine, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) e.V., Bonn, Germany,PRECISE Platform for Single Cell Genomics and Epigenomics, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) e.V. and University of Bonn, Bonn, Germany,Genomics & Immunoregulation, LIMES Institute, University of Bonn, Bonn, Germany
| | - Mark E. Graham
- Institute of Experimental Epileptology and Cognition Research, University of Bonn, University of Bonn Medical Center, Venusberg-Campus 1, 53105 Bonn, Germany
| | - Marcel Oberlaender
- In Silico Brain Sciences Group, Max-Planck Institute for Neurobiology of Behavior – Caesar, Bonn, Germany
| | - Albert Becker
- Department of Neuropathology, University Hospital Bonn, Section for Translational Epilepsy Research, 53127 Bonn, Germany
| | - Susanne Schoch
- Department of Neuropathology, University Hospital Bonn, Section for Translational Epilepsy Research, 53127 Bonn, Germany
| | - Heinz Beck
- Institute of Experimental Epileptology and Cognition Research, University of Bonn, University of Bonn Medical Center, Venusberg-Campus 1, 53105 Bonn, Germany,Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Bonn, Germany,Corresponding author
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16
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Abstract
Recent advances in genomics have revealed a wide spectrum of genetic variants associated with neurodevelopmental disorders at an unprecedented scale. An increasing number of studies have consistently identified mutations-both inherited and de novo-impacting the function of specific brain circuits. This suggests that, during brain development, alterations in distinct neural circuits, cell types, or broad regulatory pathways ultimately shaping synapses might be a dysfunctional process underlying these disorders. Here, we review findings from human studies and animal model research to provide a comprehensive description of synaptic and circuit mechanisms implicated in neurodevelopmental disorders. We discuss how specific synaptic connections might be commonly disrupted in different disorders and the alterations in cognition and behaviors emerging from imbalances in neuronal circuits. Moreover, we review new approaches that have been shown to restore or mitigate dysfunctional processes during specific critical windows of brain development. Considering the heterogeneity of neurodevelopmental disorders, we also highlight the recent progress in developing improved clinical biomarkers and strategies that will help to identify novel therapeutic compounds and opportunities for early intervention.
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Affiliation(s)
- David Exposito-Alonso
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom;
- Current affiliation: Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA;
| | - Beatriz Rico
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom;
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17
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Ma J, Li K, Sun X, Liang JN, An XQ, Tian M, Li J, Yan F, Yin Y, Yang YA, Chen FY, Zhang LQ, He XX, He ZX, Guo WX, Zhu XJ, Yu HL. Dysregulation of AMPK-mTOR signaling leads to comorbid anxiety in Dip2a KO mice. Cereb Cortex 2022; 33:4977-4989. [PMID: 36227200 DOI: 10.1093/cercor/bhac393] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 11/12/2022] Open
Abstract
Autism is often comorbid with other psychiatric disorders. We have previously shown that Dip2a knockout (KO) induces autism-like behaviors in mice. However, the role of Dip2a in other psychiatric disorders remains unclear. In this paper, we revealed that Dip2a KO mice had comorbid anxiety. Dip2a KO led to a reduction in the dendritic length of cortical and hippocampal excitatory neurons. Molecular mechanism studies suggested that AMPK was overactivated and suppressed the mTOR cascade, contributing to defects in dendritic morphology. Deletion of Dip2a in adult-born hippocampal neurons (Dip2a conditional knockout (cKO)) increased susceptibility to anxiety upon acute stress exposure. Application of (2R,6R)-hydroxynorketamine (HNK), an inhibitor of mTOR, rescued anxiety-like behaviors in Dip2a KO and Dip2a cKO mice. In addition, 6 weeks of high-fat diet intake alleviated AMPK-mTOR signaling and attenuated the severity of anxiety in both Dip2a KO mice and Dip2a cKO mice. Taken together, these results reveal an unrecognized function of DIP2A in anxiety pathophysiology via regulation of AMPK-mTOR signaling.
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Affiliation(s)
- Jun Ma
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China.,Department of Oral Anatomy and Physiology, School and Hospital of Stomatology, Jilin University, Changchun 130021, China
| | - Kai Li
- Department of Anesthesia, China-Japan Union Hospital, Jilin University, Changchun 130033, China
| | - Xue Sun
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Jia-Nan Liang
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Xian-Quan An
- Department of Anesthesiology, Second Hospital, Jilin University, Changchun 130041, China
| | - Meng Tian
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Jing Li
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Fang Yan
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Yue Yin
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Ying-Ao Yang
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Fei-Yang Chen
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Lu-Qing Zhang
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Xiao-Xiao He
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Zi-Xuan He
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Wei-Xiang Guo
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Science, Beijing 100101, China
| | - Xiao-Juan Zhu
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Hua-Li Yu
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
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18
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Riley VA, Holmberg JC, Sokolov AM, Feliciano DM. Tsc2 shapes olfactory bulb granule cell molecular and morphological characteristics. Front Mol Neurosci 2022; 15:970357. [PMID: 36277492 PMCID: PMC9581303 DOI: 10.3389/fnmol.2022.970357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Tuberous Sclerosis Complex (TSC) is a neurodevelopmental disorder caused by mutations that inactivate TSC1 or TSC2. Hamartin and tuberin are encoded by TSC1 and TSC2 which form a GTPase activating protein heteromer that inhibits the Rheb GTPase from activating a growth promoting protein kinase called mammalian target of rapamycin (mTOR). Growths and lesions occur in the ventricular-subventricular zone (V-SVZ), cortex, olfactory tract, and olfactory bulbs (OB) in TSC. A leading hypothesis is that mutations in inhibitory neural progenitor cells cause brain growths in TSC. OB granule cells (GCs) are GABAergic inhibitory neurons that are generated through infancy by inhibitory progenitor cells along the V-SVZ. Removal of Tsc1 from mouse OB GCs creates cellular phenotypes seen in TSC lesions. However, the role of Tsc2 in OB GC maturation requires clarification. Here, it is demonstrated that conditional loss of Tsc2 alters GC development. A mosaic model of TSC was created by performing neonatal CRE recombinase electroporation into inhibitory V-SVZ progenitors yielded clusters of ectopic cytomegalic neurons with hyperactive mTOR complex 1 (mTORC1) in homozygous Tsc2 mutant but not heterozygous or wild type mice. Similarly, homozygous Tsc2 mutant GC morphology was altered at postnatal days 30 and 60. Tsc2 mutant GCs had hypertrophic dendritic arbors that were established by postnatal day 30. In contrast, loss of Tsc2 from mature GCs had negligible effects on mTORC1, soma size, and dendrite arborization. OB transcriptome profiling revealed a network of significantly differentially expressed genes following loss of Tsc2 during development that altered neural circuitry. These results demonstrate that Tsc2 has a critical role in regulating neural development and shapes inhibitory GC molecular and morphological characteristics.
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19
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Molecular Mechanism and Regulation of Autophagy and Its Potential Role in Epilepsy. Cells 2022; 11:cells11172621. [PMID: 36078029 PMCID: PMC9455075 DOI: 10.3390/cells11172621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/14/2022] [Accepted: 08/22/2022] [Indexed: 01/18/2023] Open
Abstract
Autophagy is an evolutionally conserved degradation mechanism for maintaining cell homeostasis whereby cytoplasmic components are wrapped in autophagosomes and subsequently delivered to lysosomes for degradation. This process requires the concerted actions of multiple autophagy-related proteins and accessory regulators. In neurons, autophagy is dynamically regulated in different compartments including soma, axons, and dendrites. It determines the turnover of selected materials in a spatiotemporal control manner, which facilitates the formation of specialized neuronal functions. It is not surprising, therefore, that dysfunctional autophagy occurs in epilepsy, mainly caused by an imbalance between excitation and inhibition in the brain. In recent years, much attention has been focused on how autophagy may cause the development of epilepsy. In this article, we overview the historical landmarks and distinct types of autophagy, recent progress in the core machinery and regulation of autophagy, and biological roles of autophagy in homeostatic maintenance of neuronal structures and functions, with a particular focus on synaptic plasticity. We also discuss the relevance of autophagy mechanisms to the pathophysiology of epileptogenesis.
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20
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Pan X, Taherzadeh M, Bose P, Heon-Roberts R, Nguyen AL, Xu T, Pará C, Yamanaka Y, Priestman DA, Platt FM, Khan S, Fnu N, Tomatsu S, Morales CR, Pshezhetsky AV. Glucosamine amends CNS pathology in mucopolysaccharidosis IIIC mouse expressing misfolded HGSNAT. J Exp Med 2022; 219:e20211860. [PMID: 35704026 PMCID: PMC9204472 DOI: 10.1084/jem.20211860] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 02/26/2022] [Accepted: 05/02/2022] [Indexed: 02/03/2023] Open
Abstract
The majority of mucopolysaccharidosis IIIC (MPS IIIC) patients have missense variants causing misfolding of heparan sulfate acetyl-CoA:α-glucosaminide N-acetyltransferase (HGSNAT), which are potentially treatable with pharmacological chaperones. To test this approach, we generated a novel HgsnatP304L mouse model expressing misfolded HGSNAT Pro304Leu variant. HgsnatP304L mice present deficits in short-term and working/spatial memory 2-4 mo earlier than previously described constitutive knockout Hgsnat-Geo mice. HgsnatP304L mice also show augmented severity of neuroimmune response, synaptic deficits, and neuronal storage of misfolded proteins and gangliosides compared with Hgsnat-Geo mice. Expression of misfolded human Pro311Leu HGSNAT protein in cultured hippocampal Hgsnat-Geo neurons further reduced levels of synaptic proteins. Memory deficits and majority of brain pathology were rescued in mice receiving HGSNAT chaperone, glucosamine. Our data for the first time demonstrate dominant-negative effects of misfolded HGSNAT Pro304Leu variant and show that they are treatable by oral administration of glucosamine. This suggests that patients affected with mutations preventing normal folding of the enzyme can benefit from chaperone therapy.
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Affiliation(s)
- Xuefang Pan
- Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
| | - Mahsa Taherzadeh
- Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - Poulomee Bose
- Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
| | - Rachel Heon-Roberts
- Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - Annie L.A. Nguyen
- Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
| | - TianMeng Xu
- Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
| | - Camila Pará
- Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
| | - Yojiro Yamanaka
- Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
| | | | | | - Shaukat Khan
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE
| | - Nidhi Fnu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE
| | - Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE
| | - Carlos R. Morales
- Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - Alexey V. Pshezhetsky
- Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
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21
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Lim HK, Yoon JH, Song M. Autism Spectrum Disorder Genes: Disease-Related Networks and Compensatory Strategies. Front Mol Neurosci 2022; 15:922840. [PMID: 35726297 PMCID: PMC9206533 DOI: 10.3389/fnmol.2022.922840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 05/17/2022] [Indexed: 11/16/2022] Open
Abstract
The mammalian brain comprises structurally and functionally distinct regions. Each of these regions has characteristic molecular mechanisms that mediate higher-order tasks, such as memory, learning, emotion, impulse, and motor control. Many genes are involved in neuronal signaling and contribute to normal brain development. Dysfunction of essential components of neural signals leads to various types of brain disorders. Autism spectrum disorder is a neurodevelopmental disorder characterized by social deficits, communication challenges, and compulsive repetitive behaviors. Long-term genetic studies have uncovered key genes associated with autism spectrum disorder, such as SH3 and multiple ankyrin repeat domains 3, methyl-CpG binding protein 2, neurexin 1, and chromodomain helicase DNA binding protein 8. In addition, disease-associated networks have been identified using animal models, and the understanding of the impact of these genes on disease susceptibility and compensation is deepening. In this review, we examine rescue strategies using key models of autism spectrum disorder.
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Affiliation(s)
- Hye Kyung Lim
- Department of Life Sciences, Yeungnam University, Gyeongsan, South Korea
| | - Jong Hyuk Yoon
- Neurodegenerative Diseases Research Group, Korea Brain Research Institute, Daegu, South Korea
- *Correspondence: Jong Hyuk Yoon,
| | - Minseok Song
- Department of Life Sciences, Yeungnam University, Gyeongsan, South Korea
- Minseok Song,
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22
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Cossart R, Garel S. Step by step: cells with multiple functions in cortical circuit assembly. Nat Rev Neurosci 2022; 23:395-410. [DOI: 10.1038/s41583-022-00585-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/16/2022] [Indexed: 12/23/2022]
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Riemersma IW, Havekes R, Kas MJH. Spatial and Temporal Gene Function Studies in Rodents: Towards Gene-Based Therapies for Autism Spectrum Disorder. Genes (Basel) 2021; 13:28. [PMID: 35052369 PMCID: PMC8774890 DOI: 10.3390/genes13010028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/06/2021] [Accepted: 12/20/2021] [Indexed: 12/26/2022] Open
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental condition that is characterized by differences in social interaction, repetitive behaviors, restricted interests, and sensory differences beginning early in life. Especially sensory symptoms are highly correlated with the severity of other behavioral differences. ASD is a highly heterogeneous condition on multiple levels, including clinical presentation, genetics, and developmental trajectories. Over a thousand genes have been implicated in ASD. This has facilitated the generation of more than two hundred genetic mouse models that are contributing to understanding the biological underpinnings of ASD. Since the first symptoms already arise during early life, it is especially important to identify both spatial and temporal gene functions in relation to the ASD phenotype. To further decompose the heterogeneity, ASD-related genes can be divided into different subgroups based on common functions, such as genes involved in synaptic function. Furthermore, finding common biological processes that are modulated by this subgroup of genes is essential for possible patient stratification and the development of personalized early treatments. Here, we review the current knowledge on behavioral rodent models of synaptic dysfunction by focusing on behavioral phenotypes, spatial and temporal gene function, and molecular targets that could lead to new targeted gene-based therapy.
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Affiliation(s)
| | | | - Martien J. H. Kas
- Groningen Institute for Evolutionary Life Sciences, Neurobiology, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands; (I.W.R.); (R.H.)
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24
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Deng Z, Zhou X, Lu JH, Yue Z. Autophagy deficiency in neurodevelopmental disorders. Cell Biosci 2021; 11:214. [PMID: 34920755 PMCID: PMC8684077 DOI: 10.1186/s13578-021-00726-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 12/03/2021] [Indexed: 12/27/2022] Open
Abstract
Autophagy is a cell self-digestion pathway through lysosome and plays a critical role in maintaining cellular homeostasis and cytoprotection. Characterization of autophagy related genes in cell and animal models reveals diverse physiological functions of autophagy in various cell types and tissues. In central nervous system, by recycling injured organelles and misfolded protein complexes or aggregates, autophagy is integrated into synaptic functions of neurons and subjected to distinct regulation in presynaptic and postsynaptic neuronal compartments. A plethora of studies have shown the neuroprotective function of autophagy in major neurodegenerative diseases, such as Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD) and amyotrophic lateral sclerosis (ALS). Recent human genetic and genomic evidence has demonstrated an emerging, significant role of autophagy in human brain development and prevention of spectrum of neurodevelopmental disorders. Here we will review the evidence demonstrating the causal link of autophagy deficiency to congenital brain diseases, the mechanism whereby autophagy functions in neurodevelopment, and therapeutic potential of autophagy.
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Affiliation(s)
- Zhiqiang Deng
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao SAR, 999078, China
| | - Xiaoting Zhou
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.,Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Jia-Hong Lu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao SAR, 999078, China.
| | - Zhenyu Yue
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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Postnatal Sox6 Regulates Synaptic Function of Cortical Parvalbumin-Expressing Neurons. J Neurosci 2021; 41:8876-8886. [PMID: 34503995 PMCID: PMC8549537 DOI: 10.1523/jneurosci.0021-21.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 08/12/2021] [Accepted: 08/16/2021] [Indexed: 11/29/2022] Open
Abstract
Cortical parvalbumin-expressing (Pvalb+) neurons provide robust inhibition to neighboring pyramidal neurons, crucial for the proper functioning of cortical networks. This class of inhibitory neurons undergoes extensive synaptic formation and maturation during the first weeks after birth and continue to dynamically maintain their synaptic output throughout adulthood. While several transcription factors, such as Nkx2-1, Lhx6, and Sox6, are known to be necessary for the differentiation of progenitors into Pvalb+ neurons, which transcriptional programs underlie the postnatal maturation and maintenance of Pvalb+ neurons' innervation and synaptic function remains largely unknown. Because Sox6 is continuously expressed in Pvalb+ neurons until adulthood, we used conditional knock-out strategies to investigate its putative role in the postnatal maturation and synaptic function of cortical Pvalb+ neurons in mice of both sexes. We found that early postnatal loss of Sox6 in Pvalb+ neurons leads to failure of synaptic bouton growth, whereas later removal in mature Pvalb+ neurons in the adult causes shrinkage of already established synaptic boutons. Paired recordings between Pvalb+ neurons and pyramidal neurons revealed reduced release probability and increased failure rate of Pvalb+ neurons' synaptic output. Furthermore, Pvalb+ neurons lacking Sox6 display reduced expression of full-length tropomyosin-receptor kinase B (TrkB), a key modulator of GABAergic transmission. Once re-expressed in neurons lacking Sox6, TrkB was sufficient to rescue the morphologic synaptic phenotype. Finally, we showed that Sox6 mRNA levels were increased by motor training. Our data thus suggest a constitutive role for Sox6 in the maintenance of synaptic output from Pvalb+ neurons into adulthood. SIGNIFICANCE STATEMENT Cortical parvalbumin-expressing (Pvalb+) inhibitory neurons provide robust inhibition to neighboring pyramidal neurons, crucial for the proper functioning of cortical networks. These inhibitory neurons undergo extensive synaptic formation and maturation during the first weeks after birth and continue to dynamically maintain their synaptic output throughout adulthood. However, it remains largely unknown which transcriptional programs underlie the postnatal maturation and maintenance of Pvalb+ neurons. Here, we show that the transcription factor Sox6 cell-autonomously regulates the synaptic maintenance and output of Pvalb+ neurons until adulthood, leaving unaffected other maturational features of this neuronal population.
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