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Zhang Y, Liu X, Li Z, Li H, Miao Z, Wan B, Xu X. Advances on the Mechanisms and Therapeutic Strategies in Non-coding CGG Repeat Expansion Diseases. Mol Neurobiol 2024:10.1007/s12035-024-04239-9. [PMID: 38780719 DOI: 10.1007/s12035-024-04239-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 05/02/2024] [Indexed: 05/25/2024]
Abstract
Non-coding CGG repeat expansions within the 5' untranslated region are implicated in a range of neurological disorders, including fragile X-associated tremor/ataxia syndrome, oculopharyngeal myopathy with leukodystrophy, and oculopharyngodistal myopathy. This review outlined the general characteristics of diseases associated with non-coding CGG repeat expansions, detailing their clinical manifestations and neuroimaging patterns, which often overlap and indicate shared pathophysiological traits. We summarized the underlying molecular mechanisms of these disorders, providing new insights into the roles that DNA, RNA, and toxic proteins play. Understanding these mechanisms is crucial for the development of targeted therapeutic strategies. These strategies include a range of approaches, such as antisense oligonucleotides, RNA interference, genomic DNA editing, small molecule interventions, and other treatments aimed at correcting the dysregulated processes inherent in these disorders. A deeper understanding of the shared mechanisms among non-coding CGG repeat expansion disorders may hold the potential to catalyze the development of innovative therapies, ultimately offering relief to individuals grappling with these debilitating neurological conditions.
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Affiliation(s)
- Yutong Zhang
- Departments of Neurology, The First Affiliated Hospital of Soochow University, Suzhou City, China
| | - Xuan Liu
- Departments of Neurology, The First Affiliated Hospital of Soochow University, Suzhou City, China
| | - Zeheng Li
- Departments of Neurology, The First Affiliated Hospital of Soochow University, Suzhou City, China
| | - Hao Li
- Departments of Neurology, The First Affiliated Hospital of Soochow University, Suzhou City, China
- Department of Neurology, The Fourth Affiliated Hospital of Soochow University, Suzhou, 215124, China
| | - Zhigang Miao
- The Institute of Neuroscience, Soochow University, Suzhou City, China
| | - Bo Wan
- The Institute of Neuroscience, Soochow University, Suzhou City, China
| | - Xingshun Xu
- Departments of Neurology, The First Affiliated Hospital of Soochow University, Suzhou City, China.
- The Institute of Neuroscience, Soochow University, Suzhou City, China.
- Department of Neurology, The First Affiliated Hospital of Soochow University, Suzhou, 215000, China.
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2
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Takarae Y, Zanesco A, Erickson CA, Pedapati EV. EEG Microstates as Markers for Cognitive Impairments in Fragile X Syndrome. Brain Topogr 2024; 37:432-446. [PMID: 37751055 DOI: 10.1007/s10548-023-01009-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 09/12/2023] [Indexed: 09/27/2023]
Abstract
Fragile X syndrome (FXS) is one of the most common inherited causes of intellectual disabilities. While there is currently no cure for FXS, EEG is considered an important method to investigate the pathophysiology and evaluate behavioral and cognitive treatments. We conducted EEG microstate analysis to investigate resting brain dynamics in FXS participants. Resting-state recordings from 70 FXS participants and 71 chronological age-matched typically developing control (TDC) participants were used to derive microstates via modified k-means clustering. The occurrence, mean global field power (GFP), and global explained variance (GEV) of microstate C were significantly higher in the FXS group compared to the TDC group. The mean GFP was significantly negatively correlated with non-verbal IQ (NVIQ) in the FXS group, where lower NVIQ scores were associated with greater GFP. In addition, the occurrence, mean duration, mean GFP, and GEV of microstate D were significantly greater in the FXS group than the TDC group. The mean GFP and occurrence of microstate D were also correlated with individual alpha frequencies in the FXS group, where lower IAF frequencies accompanied greater microstate GFP and occurrence. Alterations in microstates C and D may be related to the two well-established cognitive characteristics of FXS, intellectual disabilities and attention impairments, suggesting that microstate parameters could serve as markers to study cognitive impairments and evaluate treatment outcomes in this population. Slowing of the alpha peak frequency and its correlation to microstate D parameters may suggest changes in thalamocortical dynamics in FXS, which could be specifically related to attention control. (250 words).
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Affiliation(s)
- Yukari Takarae
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, Sacramento, CA, USA.
- M.I.N.D. Institute, University of California, Davis, Sacramento, CA, USA.
| | - Anthony Zanesco
- Department of Psychology, University of Miami, Coral Gables, FL, USA
| | - Craig A Erickson
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Ernest V Pedapati
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
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3
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Li R, Lightbody AA, Lee CH, Bartholomay KL, Marzelli MJ, Reiss AL. Association of Intrinsic Functional Brain Network and Longitudinal Development of Cognitive Behavioral Symptoms in Young Girls With Fragile X Syndrome. Biol Psychiatry 2023; 94:814-822. [PMID: 37004849 PMCID: PMC10544666 DOI: 10.1016/j.biopsych.2023.03.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 03/01/2023] [Accepted: 03/19/2023] [Indexed: 04/04/2023]
Abstract
BACKGROUND Fragile X syndrome (FXS) is an X chromosome-linked genetic disorder characterized by increased risk for behavioral, social, and neurocognitive deficits. Because males express a more severe phenotype than females, research has focused largely on identifying neural abnormalities in all-male or both-sex populations with FXS. Therefore, very little is known about the neural alterations that contribute to cognitive behavioral symptoms in females with FXS. This cross-sectional study aimed to elucidate the large-scale resting-state brain networks associated with the multidomain cognitive behavioral phenotype in girls with FXS. METHODS We recruited 38 girls with full-mutation FXS (11.58 ± 3.15 years) and 32 girls without FXS (11.66 ± 2.27 years). Both groups were matched on age, verbal IQ, and multidomain cognitive behavioral symptoms. Resting-state functional magnetic resonance imaging data were collected. RESULTS Compared with the control group, girls with FXS showed significantly greater resting-state functional connectivity of the default mode network, lower nodal strength at the right middle temporal gyrus, stronger nodal strength at the left caudate, and higher global efficiency of the default mode network. These aberrant brain network characteristics map directly onto the cognitive behavioral symptoms commonly observed in girls with FXS. An exploratory analysis suggested that brain network patterns at a prior time point (time 1) were predictive of the longitudinal development of participants' multidomain cognitive behavioral symptoms. CONCLUSIONS These findings represent the first examination of large-scale brain network alterations in a large sample of girls with FXS, expanding our knowledge of potential neural mechanisms underlying the development of cognitive behavioral symptoms in girls with FXS.
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Affiliation(s)
- Rihui Li
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California; Center for Cognitive and Brain Sciences, Institute of Collaborative Innovation, University of Macau, Taipa, Macau S.A.R., China.
| | - Amy A Lightbody
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California
| | - Cindy H Lee
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California
| | - Kristi L Bartholomay
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California
| | - Matthew J Marzelli
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California
| | - Allan L Reiss
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California; Department of Radiology, Stanford University, Stanford, California; Department of Pediatrics, Stanford University, Stanford, California
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4
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Maurer JJ, Choi A, An I, Sathi N, Chung S. Sleep disturbances in autism spectrum disorder: Animal models, neural mechanisms, and therapeutics. Neurobiol Sleep Circadian Rhythms 2023; 14:100095. [PMID: 37188242 PMCID: PMC10176270 DOI: 10.1016/j.nbscr.2023.100095] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/16/2023] [Accepted: 04/08/2023] [Indexed: 05/17/2023] Open
Abstract
Sleep is crucial for brain development. Sleep disturbances are prevalent in children with autism spectrum disorder (ASD). Strikingly, these sleep problems are positively correlated with the severity of ASD core symptoms such as deficits in social skills and stereotypic behavior, indicating that sleep problems and the behavioral characteristics of ASD may be related. In this review, we will discuss sleep disturbances in children with ASD and highlight mouse models to study sleep disturbances and behavioral phenotypes in ASD. In addition, we will review neuromodulators controlling sleep and wakefulness and how these neuromodulatory systems are disrupted in animal models and patients with ASD. Lastly, we will address how the therapeutic interventions for patients with ASD improve various aspects of sleep. Together, gaining mechanistic insights into the neural mechanisms underlying sleep disturbances in children with ASD will help us to develop better therapeutic interventions.
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Saggar M, Bruno JL, Hall SS. Brief intensive social gaze training reorganizes functional brain connectivity in boys with fragile X syndrome. Cereb Cortex 2023; 33:5218-5227. [PMID: 36376964 PMCID: PMC10151883 DOI: 10.1093/cercor/bhac411] [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: 06/20/2022] [Revised: 09/19/2022] [Accepted: 09/20/2022] [Indexed: 11/16/2022] Open
Abstract
Boys with fragile X syndrome (FXS), the leading known genetic cause of autism spectrum disorder (ASD), demonstrate significant impairments in social gaze and associated weaknesses in communication, social interaction, and other areas of adaptive functioning. Little is known, however, concerning the impact of behavioral treatments for these behaviors on functional brain connectivity in this population. As part of a larger study, boys with FXS (mean age 13.23 ± 2.31 years) and comparison boys with ASD (mean age 12.15 ± 2.76 years) received resting-state functional magnetic resonance imaging scans prior to and following social gaze training administered by a trained behavior therapist in our laboratory. Network-agnostic connectome-based predictive modeling of pretreatment resting-state functional connectivity data revealed a set of positive (FXS > ASD) and negative (FXS < ASD) edges that differentiated the groups significantly and consistently across all folds of cross-validation. Following administration of the brief training, the FXS and ASD groups demonstrated reorganization of connectivity differences. The divergence in the spatial pattern of reorganization response, based on functional connectivity differences pretreatment, suggests a unique pattern of response to treatment in the FXS and ASD groups. These results provide further support for implementing targeted behavioral treatments to ameliorate syndrome-specific behavioral features in FXS.
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Affiliation(s)
- Manish Saggar
- Division of Interdisciplinary Brain Sciences, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, United States
| | - Jennifer L Bruno
- Division of Interdisciplinary Brain Sciences, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, United States
| | - Scott S Hall
- Division of Interdisciplinary Brain Sciences, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, United States
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Tarchi L, Damiani S, Vittori PLT, Frick A, Castellini G, Politi P, Fusar-Poli P, Ricca V. Progressive Voxel-Wise Homotopic Connectivity from childhood to adulthood: Age-related functional asymmetry in resting-state functional magnetic resonance imaging. Dev Psychobiol 2023; 65:e22366. [PMID: 36811370 DOI: 10.1002/dev.22366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 10/11/2022] [Accepted: 09/21/2022] [Indexed: 01/12/2023]
Abstract
Homotopic connectivity during resting state has been proposed as a risk marker for neurologic and psychiatric conditions, but a precise characterization of its trajectory through development is currently lacking. Voxel-Mirrored Homotopic Connectivity (VMHC) was evaluated in a sample of 85 neurotypical individuals aged 7-18 years. VMHC associations with age, handedness, sex, and motion were explored at the voxel-wise level. VMHC correlates were also explored within 14 functional networks. Primary and secondary outcomes were repeated in a sample of 107 adults aged 21-50 years. In adults, VMHC was negatively correlated with age only in the posterior insula (false discovery rate p < .05, >30-voxel clusters), while a distributed effect among the medial axis was observed in minors. Four out of 14 considered networks showed significant negative correlations between VMHC and age in minors (basal ganglia r = -.280, p = .010; anterior salience r = -.245, p = .024; language r = -.222, p = .041; primary visual r = -.257, p = .017), but not adults. In minors, a positive effect of motion on VMHC was observed only in the putamen. Sex did not significantly influence age effects on VMHC. The current study showed a specific decrease in VMHC for minors as a function of age, but not adults, supporting the notion that interhemispheric interactions can shape late neurodevelopment.
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Affiliation(s)
- Livio Tarchi
- Psychiatry Unit, Department of Health Sciences, University of Florence, Florence, Italy
| | - Stefano Damiani
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | | | - Andreas Frick
- Department of Medical Sciences, Psychiatry, Uppsala University, Uppsala, Sweden
| | - Giovanni Castellini
- Psychiatry Unit, Department of Health Sciences, University of Florence, Florence, Italy
| | - Pierluigi Politi
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Paolo Fusar-Poli
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.,Early Psychosis: Interventions and Clinical-detection (EPIC) Lab, Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,OASIS Service, South London and Maudsley NHS Foundation Trust, London, UK
| | - Valdo Ricca
- Psychiatry Unit, Department of Health Sciences, University of Florence, Florence, Italy
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Li R, Bruno JL, Lee CH, Bartholomay KL, Sundstrom J, Piccirilli A, Jordan T, Miller JG, Lightbody AA, Reiss AL. Aberrant brain network and eye gaze patterns during natural social interaction predict multi-domain social-cognitive behaviors in girls with fragile X syndrome. Mol Psychiatry 2022; 27:3768-3776. [PMID: 35595977 DOI: 10.1038/s41380-022-01626-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 05/07/2022] [Accepted: 05/12/2022] [Indexed: 02/08/2023]
Abstract
Girls with fragile X syndrome (FXS) often manifest significant symptoms of avoidance, anxiety, and arousal, particularly in the context of social interaction. However, little is currently known about the associations among neurobiological, biobehavioral such as eye gaze pattern, and social-cognitive dysfunction in real-world settings. In this study, we sought to characterize brain network properties and eye gaze patterns in girls with FXS during natural social interaction. Participants included 42 girls with FXS and 31 age- and verbal IQ-matched girls (control). Portable functional near-infrared spectroscopy (fNIRS) and an eye gaze tracker were used to investigate brain network alterations and eye gaze patterns associated with social-cognitive dysfunction in girls with FXS during a structured face-to-face conversation. Compared to controls, girls with FXS showed significantly increased inter-regional functional connectivity and greater excitability within the prefrontal cortex (PFC), frontal eye field (FEF) and superior temporal gyrus (STG) during the conversation. Girls with FXS showed significantly less eye contact with their conversational partner and more unregulated eye gaze behavior compared to the control group. We also demonstrated that a machine learning approach based on multimodal data, including brain network properties and eye gaze patterns, was predictive of multiple domains of social-cognitive behaviors in girls with FXS. Our findings expand current knowledge of neural mechanisms and eye gaze behaviors underlying naturalistic social interaction in girls with FXS. These results could be further evaluated and developed as intermediate phenotypic endpoints for treatment trial evaluation in girls with FXS.
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Affiliation(s)
- Rihui Li
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA.
| | - Jennifer L Bruno
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Cindy H Lee
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Kristi L Bartholomay
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Jamie Sundstrom
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Aaron Piccirilli
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Tracy Jordan
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Jonas G Miller
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Amy A Lightbody
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Allan L Reiss
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
- Departments of Radiology and Pediatrics, Stanford University, Stanford, CA, 94305, USA
- Department of Pediatrics, Stanford University, Stanford, CA, 94305, USA
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8
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Pedapati EV, Schmitt LM, Ethridge LE, Miyakoshi M, Sweeney JA, Liu R, Smith E, Shaffer RC, Dominick KC, Gilbert DL, Wu SW, Horn PS, Binder DK, Lamy M, Axford M, Erickson CA. Neocortical localization and thalamocortical modulation of neuronal hyperexcitability contribute to Fragile X Syndrome. Commun Biol 2022; 5:442. [PMID: 35546357 PMCID: PMC9095835 DOI: 10.1038/s42003-022-03395-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 04/22/2022] [Indexed: 12/13/2022] Open
Abstract
Fragile X Syndrome (FXS) is a monogenetic form of intellectual disability and autism in which well-established knockout (KO) animal models point to neuronal hyperexcitability and abnormal gamma-frequency physiology as a basis for key disorder features. Translating these findings into patients may identify tractable treatment targets. Using source modeling of resting-state electroencephalography data, we report findings in FXS, including 1) increases in localized gamma activity, 2) pervasive changes of theta/alpha activity, indicative of disrupted thalamocortical modulation coupled with elevated gamma power, 3) stepwise moderation of low and high-frequency abnormalities based on female sex, and 4) relationship of this physiology to intellectual disability and neuropsychiatric symptoms. Our observations extend findings in Fmr1-/- KO mice to patients with FXS and raise a key role for disrupted thalamocortical modulation in local hyperexcitability. This systems-level mechanism has received limited preclinical attention but has implications for understanding fundamental disease mechanisms.
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Affiliation(s)
- Ernest V Pedapati
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
| | - Lauren M Schmitt
- Division of Developmental and Behavioral Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Lauren E Ethridge
- Department of Pediatrics, Section on Developmental and Behavioral Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Psychology, University of Oklahoma, Norman, OK, USA
| | - Makoto Miyakoshi
- Swartz Center for Computational Neuroscience, Institute for Neural Computation, University of California San Diego, La Jolla, CA, USA
| | - John A Sweeney
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Rui Liu
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Elizabeth Smith
- Division of Developmental and Behavioral Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Rebecca C Shaffer
- Division of Developmental and Behavioral Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Kelli C Dominick
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Donald L Gilbert
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Steve W Wu
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Paul S Horn
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Devin K Binder
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, CA, USA
| | - Martine Lamy
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Megan Axford
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Craig A Erickson
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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9
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Zerbi V, Pagani M, Markicevic M, Matteoli M, Pozzi D, Fagiolini M, Bozzi Y, Galbusera A, Scattoni ML, Provenzano G, Banerjee A, Helmchen F, Basson MA, Ellegood J, Lerch JP, Rudin M, Gozzi A, Wenderoth N. Brain mapping across 16 autism mouse models reveals a spectrum of functional connectivity subtypes. Mol Psychiatry 2021; 26:7610-7620. [PMID: 34381171 PMCID: PMC8873017 DOI: 10.1038/s41380-021-01245-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 06/30/2021] [Accepted: 07/20/2021] [Indexed: 02/07/2023]
Abstract
Autism Spectrum Disorder (ASD) is characterized by substantial, yet highly heterogeneous abnormalities in functional brain connectivity. However, the origin and significance of this phenomenon remain unclear. To unravel ASD connectopathy and relate it to underlying etiological heterogeneity, we carried out a bi-center cross-etiological investigation of fMRI-based connectivity in the mouse, in which specific ASD-relevant mutations can be isolated and modeled minimizing environmental contributions. By performing brain-wide connectivity mapping across 16 mouse mutants, we show that different ASD-associated etiologies cause a broad spectrum of connectional abnormalities in which diverse, often diverging, connectivity signatures are recognizable. Despite this heterogeneity, the identified connectivity alterations could be classified into four subtypes characterized by discrete signatures of network dysfunction. Our findings show that etiological variability is a key determinant of connectivity heterogeneity in ASD, hence reconciling conflicting findings in clinical populations. The identification of etiologically-relevant connectivity subtypes could improve diagnostic label accuracy in the non-syndromic ASD population and paves the way for personalized treatment approaches.
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Affiliation(s)
- V Zerbi
- Neural Control of Movement Lab, ETH Zurich, Zurich, Switzerland
| | - M Pagani
- Functional Neuroimaging Lab, Istituto Italiano di Tecnologia, Center for Neuroscience and Cognitive Systems, Rovereto, Italy
| | - M Markicevic
- Neural Control of Movement Lab, ETH Zurich, Zurich, Switzerland
| | - M Matteoli
- Laboratory of Pharmacology and Brain Pathology, Neurocenter, Humanitas Clinical and Research Center - IRCCS, Rozzano, Mi, Italy
- CNR Institute of Neuroscience, Milano, Italy
| | - D Pozzi
- Laboratory of Pharmacology and Brain Pathology, Neurocenter, Humanitas Clinical and Research Center - IRCCS, Rozzano, Mi, Italy
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
| | - M Fagiolini
- F.M. Kirby Neurobiology Department, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Y Bozzi
- Center for Mind/Brain Sciences (CIMeC), University of Trento, Rovereto, Italy
| | - A Galbusera
- Functional Neuroimaging Lab, Istituto Italiano di Tecnologia, Center for Neuroscience and Cognitive Systems, Rovereto, Italy
| | - M L Scattoni
- Research Coordination and Support Service, Istituto Superiore di Sanità, Rome, Italy
| | - G Provenzano
- Department of Cellular, Computational and Integrative Biology. (CIBIO), University of Trento, Trento, Italy
| | - A Banerjee
- Brain Research Institute, University of Zurich, Zurich, Switzerland
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - F Helmchen
- Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - M A Basson
- Centre for Craniofacial and Regenerative Biology, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King's College, London, London, UK
| | - J Ellegood
- Mouse Imaging Ctr., Hosp. For Sick Children, Toronto, ON, Canada
| | - J P Lerch
- Mouse Imaging Ctr., Hosp. For Sick Children, Toronto, ON, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - M Rudin
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - A Gozzi
- Functional Neuroimaging Lab, Istituto Italiano di Tecnologia, Center for Neuroscience and Cognitive Systems, Rovereto, Italy.
| | - N Wenderoth
- Neural Control of Movement Lab, ETH Zurich, Zurich, Switzerland
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10
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Wang X, Zhen Z, Xu S, Li J, Song Y, Liu J. Behavioral and neural correlates of social network size: The unique and common contributions of face recognition and extraversion. J Pers 2021; 90:294-305. [PMID: 34358350 DOI: 10.1111/jopy.12666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 07/27/2021] [Accepted: 08/02/2021] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Humans are inherently social creatures and can gain advantages from larger network size. Researches have shown that different cognitive and personality factors may result in individual differences of social network size (SNS). Here, we focused on whether face recognition ability and extraversion were related to SNS and the neural basis underlying the relations. METHODS Behaviorally, we adopted the face-inversion task, NEO personality inventory, and computerized SNS test to explore the relationships between face recognition, extraversion, and SNS. Neurally, we used resting state functional magnetic resonance imaging and fractional amplitude of low-frequency fluctuation (fALFF) analysis method to investigate the neural correlates of SNS and then revealed whether face recognition and extraversion were related to SNS relevant brain regions. RESULTS We found that individuals with better face recognition ability and more extraverted personality had larger size of social network. In addition, we found that SNS was positively associated with the fALFF in the ventromedial prefrontal cortex (vmPFC), right superior temporal sulcus, and precuneus. Interestingly, the fALFF in the vmPFC significantly correlated with face recognition ability. CONCLUSIONS Our study suggests that both face recognition and extraversion may be important correlates of SNS, and the underlying spontaneous neural substrates are partially dissociable.
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Affiliation(s)
- Xu Wang
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
| | - Zonglei Zhen
- Faculty of Psychology, Beijing Normal University, Beijing, China
| | - Shan Xu
- Faculty of Psychology, Beijing Normal University, Beijing, China
| | - Jingguang Li
- College of Teacher Education, Dali University, Dali, China
| | - Yiying Song
- Faculty of Psychology, Beijing Normal University, Beijing, China
| | - Jia Liu
- Department of Psychology, Tsinghua Laboratory of Brain and Intelligence, Tsinghua University, Beijing, China
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11
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Mody M, Petibon Y, Han P, Kuruppu D, Ma C, Yokell D, Neelamegam R, Normandin MD, Fakhri GE, Brownell AL. In vivo imaging of mGlu5 receptor expression in humans with Fragile X Syndrome towards development of a potential biomarker. Sci Rep 2021; 11:15897. [PMID: 34354107 PMCID: PMC8342610 DOI: 10.1038/s41598-021-94967-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/16/2021] [Indexed: 11/21/2022] Open
Abstract
Fragile X Syndrome (FXS) is a neurodevelopmental disorder caused by silencing of the Fragile X Mental Retardation (FMR1) gene. The resulting loss of Fragile X Mental Retardation Protein (FMRP) leads to excessive glutamate signaling via metabotropic glutamate subtype 5 receptors (mGluR5) which has been implicated in the pathogenesis of the disorder. In the present study we used the radioligand 3-[18F]fluoro-5-(2-pyridinylethynyl)benzonitrile ([18F]FPEB) in simultaneous PET-MR imaging of males with FXS and age- and gender-matched controls to assess the availability of mGlu5 receptors in relevant brain areas. Patients with FXS showed lower [18F]FPEB binding potential (p < 0.01), reflecting reduced mGluR5 availability, than the healthy controls throughout the brain, with significant group differences in insula, anterior cingulate, parahippocampal, inferior temporal and olfactory cortices, regions associated with deficits in inhibition, memory, and visuospatial processes characteristic of the disorder. The results are among the first to provide in vivo evidence of decreased availability of mGluR5 in the brain in individuals with FXS than in healthy controls. The consistent results across the subjects, despite the tremendous challenges with neuroimaging this population, highlight the robustness of the protocol and support for its use in drug occupancy studies; extending our radiotracer development and application efforts from mice to humans.
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Affiliation(s)
- Maria Mody
- Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA.
| | - Yoann Petibon
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Paul Han
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Darshini Kuruppu
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Chao Ma
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Daniel Yokell
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Ramesh Neelamegam
- Department of Radiology, University of Texas Health Science at San Antonio, San Antonio, TX, 78229, USA
| | - Marc D Normandin
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Anna-Liisa Brownell
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
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12
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Whitman ET, Liu S, Torres E, Warling A, Wilson K, Nadig A, McDermott C, Clasen LS, Blumenthal JD, Lalonde FM, Gotts SJ, Martin A, Raznahan A. Resting-State Functional Connectivity and Psychopathology in Klinefelter Syndrome (47, XXY). Cereb Cortex 2021; 31:4180-4190. [PMID: 34009243 PMCID: PMC8485146 DOI: 10.1093/cercor/bhab077] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Klinefelter syndrome (47, XXY; henceforth: XXY syndrome) is a high-impact but poorly understood genetic risk factor for neuropsychiatric impairment. Here, we provide the first study to map alterations of functional brain connectivity in XXY syndrome and relate these changes to brain anatomy and psychopathology. We used resting-state functional magnetic resonance imaging data from 75 individuals with XXY and 84 healthy XY males to 1) implement a brain-wide screen for altered global resting-state functional connectivity (rsFC) in XXY versus XY males and 2) decompose these alterations through seed-based analysis. We then compared these rsFC findings with measures of regional brain anatomy, psychopathology, and cognition. XXY syndrome was characterized by increased global rsFC in the left dorsolateral prefrontal cortex (DLPFC)-reflecting DLPFC overconnectivity with diverse rsFC networks. Functional overconnectivity was partly coupled to co-occurring regional volumetric changes in XXY syndrome, and variation in DLPFC-precuneus rsFC was correlated with the severity of psychopathology. By providing the first view of altered rsFC in XXY syndrome and contextualizing observed changes relative to neuroanatomy and behavior, our study helps to advance biological understanding of XXY syndrome-both as a disorder in its own right and more broadly as a model of genetic risk for psychopathology.
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Affiliation(s)
- Ethan T Whitman
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Siyuan Liu
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Erin Torres
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Allysa Warling
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Kathleen Wilson
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Ajay Nadig
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Cassidy McDermott
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Liv S Clasen
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Jonathan D Blumenthal
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - François M Lalonde
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Stephen J Gotts
- Section on Cognitive Neuropsychology, Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Alex Martin
- Section on Cognitive Neuropsychology, Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD 20814, USA
| | - Armin Raznahan
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20814, USA
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13
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Booker SA, Kind PC. Mechanisms regulating input-output function and plasticity of neurons in the absence of FMRP. Brain Res Bull 2021; 175:69-80. [PMID: 34245842 DOI: 10.1016/j.brainresbull.2021.06.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/13/2021] [Accepted: 06/29/2021] [Indexed: 12/12/2022]
Abstract
The function of brain circuits relies on high-fidelity information transfer within neurons. Synaptic inputs arrive primarily at dendrites, where they undergo integration and summation throughout the somatodendritic domain, ultimately leading to the generation of precise patterns of action potentials. Emerging evidence suggests that the ability of neurons to transfer synaptic information and modulate their output is impaired in a number of neurodevelopmental disorders including Fragile X Syndrome. In this review we summarise recent findings that have revealed the pathophysiological and plasticity mechanisms that alter the ability of neurons in sensory and limbic circuits to reliably code information in the absence of FMRP. We examine which aspects of this transform may result directly from the loss of FMRP and those that a result from compensatory or homeostatic alterations to neuronal function. Dissection of the mechanisms leading to altered input-output function of neurons in the absence of FMRP and their effects on regulating neuronal plasticity throughout development could have important implications for potential therapies for Fragile X Syndrome, including directing the timing and duration of different treatment options.
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Affiliation(s)
- Sam A Booker
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK; Patrick Wild Centre for Autism Research, University of Edinburgh, Edinburgh, UK; Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.
| | - Peter C Kind
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK; Patrick Wild Centre for Autism Research, University of Edinburgh, Edinburgh, UK; Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK; National Centre for Biological Sciences (NCBS), Bangalore, India.
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14
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Wen J, Xu J, Mathena RP, Choi JH, Mintz CD. Early Isoflurane Exposure Impairs Synaptic Development in Fmr1 KO Mice via the mTOR Pathway. Neurochem Res 2021; 46:1577-1588. [PMID: 33791908 DOI: 10.1007/s11064-021-03301-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/23/2021] [Accepted: 03/17/2021] [Indexed: 12/16/2022]
Abstract
General anesthetics (GAs) may cause disruptions in brain development, and the effect of GA exposure in the setting of pre-existing neurodevelopmental disease is unknown. We tested the hypothesis that synaptic development is more vulnerable to GA-induced deficits in a mouse model of fragile X syndrome than in WT mice and asked whether they were related to the mTOR pathway, a signaling system implicated in both anesthesia toxicity and fragile X syndrome. Early postnatal WT and Fmr1-KO mice were exposed to isoflurane and brain slices were collected in adulthood. Primary neuron cultures isolated from WT and Fmr1-KO mice were exposed to isoflurane during development, in some cases treated with rapamycin, and processed for immunohistochemistry at maturity. Quantitative immunofluorescence microscopy was conducted for synaptic markers and markers of mTOR pathway activity. Isoflurane exposure caused reduction in Synpasin-1, PSD-95, and Gephyrin puncta that was significantly lower in Fmr1-KO mice than in WT mice. Similar results were found in cell culture, where synapse loss was ameliorated with rapamycin treatment. Early developmental exposure to isoflurane causes more profound synapse loss in Fmr1- KO than WT mice, and this effect is mediated by a pathologic increase in mTOR pathway activity.
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Affiliation(s)
- Jieqiong Wen
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, China
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Jing Xu
- Department of Anesthesiology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - R Paige Mathena
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Jun H Choi
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - C David Mintz
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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15
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Reduced axonal caliber and structural changes in a rat model of Fragile X syndrome with a deletion of a K-Homology domain of Fmr1. Transl Psychiatry 2020; 10:280. [PMID: 32788572 PMCID: PMC7423986 DOI: 10.1038/s41398-020-00943-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 04/15/2020] [Accepted: 04/21/2020] [Indexed: 12/30/2022] Open
Abstract
Fragile X syndrome (FXS) is a neurodevelopmental disorder that is caused by mutations in the FMR1 gene. Neuroanatomical alterations have been reported in both male and female individuals with FXS, yet the morphological underpinnings of these alterations have not been elucidated. In the current study, we found structural changes in both male and female rats that model FXS, some of which are similarly impaired in both sexes, including the superior colliculus and periaqueductal gray, and others that show sex-specific changes. The splenium of the corpus callosum, for example, was only impaired in males. We also found reduced axonal caliber in the splenium, offering a mechanism for its structural changes. Furthermore, we found that overall, male rats have higher brain-wide diffusion than female rats. Our results provide insight into which brain regions are vulnerable to a loss of Fmr1 expression and reveal an impairment at the level of the axon that could cause structural changes in white matter regions.
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16
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Razak KA, Dominick KC, Erickson CA. Developmental studies in fragile X syndrome. J Neurodev Disord 2020; 12:13. [PMID: 32359368 PMCID: PMC7196229 DOI: 10.1186/s11689-020-09310-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 02/13/2020] [Indexed: 01/27/2023] Open
Abstract
Fragile X syndrome (FXS) is the most common single gene cause of autism and intellectual disabilities. Humans with FXS exhibit increased anxiety, sensory hypersensitivity, seizures, repetitive behaviors, cognitive inflexibility, and social behavioral impairments. The main purpose of this review is to summarize developmental studies of FXS in humans and in the mouse model, the Fmr1 knockout mouse. The literature presents considerable evidence that a number of early developmental deficits can be identified and that these early deficits chart a course of altered developmental experience leading to symptoms well characterized in adolescents and adults. Nevertheless, a number of critical issues remain unclear or untested regarding the development of symptomology and underlying mechanisms. First, what is the role of FMRP, the protein product of Fmr1 gene, during different developmental ages? Does the absence of FMRP during early development lead to irreversible changes, or could reintroduction of FMRP or therapeutics aimed at FMRP-interacting proteins/pathways hold promise when provided in adults? These questions have implications for clinical trial designs in terms of optimal treatment windows, but few studies have systematically addressed these issues in preclinical and clinical work. Published studies also point to complex trajectories of symptom development, leading to the conclusion that single developmental time point studies are unlikely to disambiguate effects of genetic mutation from effects of altered developmental experience and compensatory plasticity. We conclude by suggesting a number of experiments needed to address these major gaps in the field.
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Affiliation(s)
- Khaleel A Razak
- Department of Psychology and Graduate Neuroscience Program, University of California, Riverside, USA
| | - Kelli C Dominick
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA.,Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue MLC 4002, Cincinnati, OH, 45229, USA
| | - Craig A Erickson
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA. .,Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue MLC 4002, Cincinnati, OH, 45229, USA.
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17
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McKechanie AG, Campbell S, Eley SEA, Stanfield AC. Autism in Fragile X Syndrome; A Functional MRI Study of Facial Emotion-Processing. Genes (Basel) 2019; 10:genes10121052. [PMID: 31861230 PMCID: PMC6947308 DOI: 10.3390/genes10121052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 11/25/2019] [Accepted: 12/13/2019] [Indexed: 11/16/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability and autism spectrum disorder, and among those with fragile X syndrome, approximately 1/3rd meet a threshold for an autism spectrum disorder (ASD) diagnosis. Previous functional imaging studies of fragile X syndrome have typically focused on those with fragile X syndrome compared to either neurotypical or autism spectrum disorder control groups. Further, the majority of previous studies have tended to focus on those who are more intellectually able than is typical for fragile X syndrome. In this study, we examine the impact of autistic traits in individuals with fragile X syndrome on a paradigm looking at facial emotion processing. The study included 17 individuals with fragile X syndrome, of whom 10 met criteria for autism as measured by the Autism Diagnostic Observation Schedule (ADOS). Prior to the scan, participants rehearsed on a mock scanner to help acclimatize to the scanner environment and thus allow more severely affected individuals to participate. The task examined the blood-oxygen-level-dependent (BOLD) response to fearful and neutral faces taken from the Ekman faces series. Individuals in the autism group had a region of significantly reduced activity centered on the left superior temporal gyrus, compared to those with FXS alone, in response to the fearful faces. We suggest that autism in individuals with fragile X syndrome is associated with similar changes in the neurobiology of facial emotion processing as seen in idiopathic autism.
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Affiliation(s)
- Andrew G. McKechanie
- The Patrick Wild Centre, The University of Edinburgh, Edinburgh EH10 5HF, UK; (S.C.); (S.E.A.E.); (A.C.S.)
- NHS Lothian, Edinburgh EH1 3EG, UK
- Correspondence: ; Tel.: +44-131-537-6000
| | - Sonya Campbell
- The Patrick Wild Centre, The University of Edinburgh, Edinburgh EH10 5HF, UK; (S.C.); (S.E.A.E.); (A.C.S.)
| | - Sarah E. A. Eley
- The Patrick Wild Centre, The University of Edinburgh, Edinburgh EH10 5HF, UK; (S.C.); (S.E.A.E.); (A.C.S.)
| | - Andrew C. Stanfield
- The Patrick Wild Centre, The University of Edinburgh, Edinburgh EH10 5HF, UK; (S.C.); (S.E.A.E.); (A.C.S.)
- NHS Lothian, Edinburgh EH1 3EG, UK
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18
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Insular Cortex Projections to Nucleus Accumbens Core Mediate Social Approach to Stressed Juvenile Rats. J Neurosci 2019; 39:8717-8729. [PMID: 31591155 DOI: 10.1523/jneurosci.0316-19.2019] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 08/30/2019] [Accepted: 09/18/2019] [Indexed: 02/07/2023] Open
Abstract
Social interactions are shaped by features of the interactants, including age, emotion, sex, and familiarity. Age-specific responses to social affect are evident when an adult male rat is presented with a pair of unfamiliar male conspecifics, one of which is stressed via two foot shocks and the other naive to treatment. Adult test rats prefer to interact with stressed juvenile (postnatal day 30, PN30) conspecifics but avoid stressed adult (PN50) conspecifics. This pattern depends upon the insular cortex (IC), which is anatomically connected to the nucleus accumbens core (NAc). The goal of this work was to test the necessity of IC projections to NAc during social affective behavior. Here, bilateral pharmacological inhibition of the NAc with tetrodotoxin (1 μm; 0.5 μl/side) abolished the preference for stressed PN30, but did not alter interactions with PN50 conspecifics. Using a combination of retrograding tracing and c-Fos immunohistochemistry, we report that social interactions with stressed PN30 conspecifics elicit greater Fos immunoreactivity in IC → NAc neurons than interactions with naive PN30 conspecifics. Chemogenetic stimulation of IC terminals in the NAc increased social exploration with juvenile, but not adult, conspecifics, whereas chemogenetic inhibition of this tract blocked the preference to investigate stressed PN30 conspecifics, which expands upon our previous finding that optogenetic inhibition of IC projection neurons mediated approach and avoidance. These new findings suggest that outputs of IC to the NAc modulate social approach, which provides new insight to the neural circuitry underlying social decision-making.SIGNIFICANCE STATEMENT Social decision-making underlies an animal's behavioral response to others in a range of social contexts. Previous findings indicate the insular cortex (IC) and the nucleus accumbens (NAc) play important roles in social behaviors, and human neuroimaging implicates both IC and NAc in autism and other psychiatric disorders characterized by aberrant social cognition. To test whether IC projections to the NAc are involved in social decision-making, circuit-specific chemogenetic manipulations demonstrated that the IC → NAc pathway mediates social approach toward distressed juvenile, but not adult, conspecifics. This finding is the first to implicate this circuit in rodent socioemotional behaviors and may be a neuroanatomical substrate for integration of emotion with social reward.
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19
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Cogram P, Deacon RMJ, Warner-Schmidt JL, von Schimmelmann MJ, Abrahams BS, During MJ. Gaboxadol Normalizes Behavioral Abnormalities in a Mouse Model of Fragile X Syndrome. Front Behav Neurosci 2019; 13:141. [PMID: 31293404 PMCID: PMC6603241 DOI: 10.3389/fnbeh.2019.00141] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/07/2019] [Indexed: 12/11/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited form of intellectual disability and autism. FXS is also accompanied by attention problems, hyperactivity, anxiety, aggression, poor sleep, repetitive behaviors, and self-injury. Recent work supports the role of γ-aminobutyric-acid (GABA), the primary inhibitory neurotransmitter in the brain, in mediating symptoms of FXS. Deficits in GABA machinery have been observed in a mouse model of FXS, including a loss of tonic inhibition in the amygdala, which is mediated by extrasynaptic GABAA receptors. Humans with FXS also show reduced GABAA receptor availability. Here, we sought to evaluate the potential of gaboxadol (also called OV101 and THIP), a selective and potent agonist for delta-subunit-containing extrasynaptic GABAA receptors (dSEGA), as a therapeutic agent for FXS by assessing its ability to normalize aberrant behaviors in a relatively uncharacterized mouse model of FXS (Fmr1 KO2 mice). Four behavioral domains (hyperactivity, anxiety, aggression, and repetitive behaviors) were probed using a battery of behavioral assays. The results showed that Fmr1 KO2 mice were hyperactive, had abnormal anxiety-like behavior, were more irritable and aggressive, and had an increased frequency of repetitive behaviors compared to wild-type (WT) littermates, which are all behavioral deficits reminiscent of individuals with FXS. Treatment with gaboxadol normalized all of the aberrant behaviors observed in Fmr1 KO2 mice back to WT levels, providing evidence of its potential benefit for treating FXS. We show that the potentiation of extrasynaptic GABA receptors alone, by gaboxadol, is sufficient to normalize numerous behavioral deficits in the FXS model using endpoints that are directly translatable to the clinical presentation of FXS. Taken together, these data support the future evaluation of gaboxadol in individuals with FXS, particularly with regard to symptoms of hyperactivity, anxiety, irritability, aggression, and repetitive behaviors.
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Affiliation(s)
- Patricia Cogram
- FRAXA-DVI, FRAXA Research Foundation, Boston, MA, United States.,Centre for Systems Biotechnology, Biomedicine Division, Fraunhofer-Gesellschaft, Santiago, Chile.,GEN.DDI Limited, London, United Kingdom.,Institute of Ecology and Biodiversity (IEB), University of Chile, Santiago, Chile
| | - Robert M J Deacon
- FRAXA-DVI, FRAXA Research Foundation, Boston, MA, United States.,Centre for Systems Biotechnology, Biomedicine Division, Fraunhofer-Gesellschaft, Santiago, Chile.,GEN.DDI Limited, London, United Kingdom.,Institute of Ecology and Biodiversity (IEB), University of Chile, Santiago, Chile
| | | | | | - Brett S Abrahams
- Ovid Therapeutics, New York, NY, United States.,Department of Genetics and Neuroscience, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Matthew J During
- Ovid Therapeutics, New York, NY, United States.,Department of Neurological Surgery and Molecular Virology, Immunology and Medical Genetics, Ohio State University College of Medicine, Columbus, OH, United States
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20
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Fernandez A, Meechan DW, Karpinski BA, Paronett EM, Bryan CA, Rutz HL, Radin EA, Lubin N, Bonner ER, Popratiloff A, Rothblat LA, Maynard TM, LaMantia AS. Mitochondrial Dysfunction Leads to Cortical Under-Connectivity and Cognitive Impairment. Neuron 2019; 102:1127-1142.e3. [PMID: 31079872 PMCID: PMC6668992 DOI: 10.1016/j.neuron.2019.04.013] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 02/21/2019] [Accepted: 04/03/2019] [Indexed: 12/17/2022]
Abstract
Under-connectivity between cerebral cortical association areas may underlie cognitive deficits in neurodevelopmental disorders, including the 22q11.2 deletion syndrome (22q11DS). Using the LgDel 22q11DS mouse model, we assessed cellular, molecular, and developmental origins of under-connectivity and its consequences for cognitive function. Diminished 22q11 gene dosage reduces long-distance projections, limits axon and dendrite growth, and disrupts mitochondrial and synaptic integrity in layer 2/3 but not 5/6 projection neurons (PNs). Diminished dosage of Txnrd2, a 22q11 gene essential for reactive oxygen species catabolism in brain mitochondria, recapitulates these deficits in WT layer 2/3 PNs; Txnrd2 re-expression in LgDel layer 2/3 PNs rescues them. Anti-oxidants reverse LgDel- or Txnrd2-related layer 2/3 mitochondrial, circuit, and cognitive deficits. Accordingly, Txnrd2-mediated oxidative stress reduces layer 2/3 connectivity and impairs cognition in the context of 22q11 deletion. Anti-oxidant restoration of mitochondrial integrity, cortical connectivity, and cognitive behavior defines oxidative stress as a therapeutic target in neurodevelopmental disorders.
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Affiliation(s)
- Alejandra Fernandez
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA; GW Institute for Biomedical Sciences, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20037, USA
| | - Daniel W Meechan
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA
| | - Beverly A Karpinski
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA
| | - Elizabeth M Paronett
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA
| | - Corey A Bryan
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA
| | - Hanna L Rutz
- Department of Psychology, The George Washington University, Washington, DC 20037, USA
| | - Eric A Radin
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA
| | - Noah Lubin
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA
| | - Erin R Bonner
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA
| | - Anastas Popratiloff
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA
| | - Lawrence A Rothblat
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Psychology, The George Washington University, Washington, DC 20037, USA
| | - Thomas M Maynard
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA
| | - Anthony-Samuel LaMantia
- GW Institute for Neuroscience, The George Washington University, Washington, DC 20037, USA; Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037, USA.
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21
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Lee FHF, Lai TKY, Su P, Liu F. Altered cortical Cytoarchitecture in the Fmr1 knockout mouse. Mol Brain 2019; 12:56. [PMID: 31200759 PMCID: PMC6570929 DOI: 10.1186/s13041-019-0478-8] [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: 04/10/2019] [Accepted: 06/03/2019] [Indexed: 12/15/2022] Open
Abstract
Fragile X syndrome (FXS) is a neurodevelopmental disorder caused by silencing of the FMR1 gene and subsequent loss of its protein product, fragile X retardation protein (FMRP). One of the most robust neuropathological findings in post-mortem human FXS and Fmr1 KO mice is the abnormal increase in dendritic spine densities, with the majority of spines showing an elongated immature morphology. However, the exact mechanisms of how FMRP can regulate dendritic spine development are still unclear. Abnormal dendritic spines can result from disturbances of multiple factors during neurodevelopment, such as alterations in neuron numbers, position and glial cells. In this study, we undertook a comprehensive histological analysis of the cerebral cortex in Fmr1 KO mice. They displayed significantly fewer neuron and PV-interneuron numbers, along with altered cortical lamination patterns. In terms of glial cells, Fmr1 KO mice exhibited an increase in Olig2-oligodendrocytes, which corresponded to the abnormally higher myelin expression in the corpus callosum. Iba1-microglia were significantly reduced but GFAP-astrocyte numbers and intensity were elevated. Using primary astrocytes derived from KO mice, we further demonstrated the presence of astrogliosis characterized by an increase in GFAP expression and astrocyte hypertrophy. Our findings provide important information on the cortical architecture of Fmr1 KO mice, and insights towards possible mechanisms associated with FXS.
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Affiliation(s)
- Frankie H F Lee
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8, Canada
| | - Terence K Y Lai
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, M5T 1R8, Canada
| | - Ping Su
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8, Canada
| | - Fang Liu
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8, Canada. .,Department of Physiology, University of Toronto, Toronto, Ontario, M5T 1R8, Canada. .,Department of Psychiatry, University of Toronto, Toronto, Ontario, M5T 1R8, Canada.
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22
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Zerbi V, Markicevic M, Gasparini F, Schroeter A, Rudin M, Wenderoth N. Inhibiting mGluR5 activity by AFQ056/Mavoglurant rescues circuit-specific functional connectivity in Fmr1 knockout mice. Neuroimage 2019; 191:392-402. [DOI: 10.1016/j.neuroimage.2019.02.051] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 02/11/2019] [Accepted: 02/19/2019] [Indexed: 12/12/2022] Open
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23
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Bagni C, Zukin RS. A Synaptic Perspective of Fragile X Syndrome and Autism Spectrum Disorders. Neuron 2019; 101:1070-1088. [PMID: 30897358 PMCID: PMC9628679 DOI: 10.1016/j.neuron.2019.02.041] [Citation(s) in RCA: 195] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 02/25/2019] [Accepted: 02/27/2019] [Indexed: 12/28/2022]
Abstract
Altered synaptic structure and function is a major hallmark of fragile X syndrome (FXS), autism spectrum disorders (ASDs), and other intellectual disabilities (IDs), which are therefore classified as synaptopathies. FXS and ASDs, while clinically and genetically distinct, share significant comorbidity, suggesting that there may be a common molecular and/or cellular basis, presumably at the synapse. In this article, we review brain architecture and synaptic pathways that are dysregulated in FXS and ASDs, including spine architecture, signaling in synaptic plasticity, local protein synthesis, (m)RNA modifications, and degradation. mRNA repression is a powerful mechanism for the regulation of synaptic structure and efficacy. We infer that there is no single pathway that explains most of the etiology and discuss new findings and the implications for future work directed at improving our understanding of the pathogenesis of FXS and related ASDs and the design of therapeutic strategies to ameliorate these disorders.
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Affiliation(s)
- Claudia Bagni
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland; Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy.
| | - R Suzanne Zukin
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, New York City, NY, USA.
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24
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Zerbi V, Ielacqua GD, Markicevic M, Haberl MG, Ellisman MH, A-Bhaskaran A, Frick A, Rudin M, Wenderoth N. Dysfunctional Autism Risk Genes Cause Circuit-Specific Connectivity Deficits With Distinct Developmental Trajectories. Cereb Cortex 2018; 28:2495-2506. [PMID: 29901787 PMCID: PMC5998961 DOI: 10.1093/cercor/bhy046] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 01/16/2018] [Accepted: 02/12/2018] [Indexed: 12/22/2022] Open
Abstract
Autism spectrum disorders (ASD) are a set of complex neurodevelopmental disorders for which there is currently no targeted therapeutic approach. It is thought that alterations of genes regulating migration and synapse formation during development affect neural circuit formation and result in aberrant connectivity within distinct circuits that underlie abnormal behaviors. However, it is unknown whether deviant developmental trajectories are circuit-specific for a given autism risk-gene. We used MRI to probe changes in functional and structural connectivity from childhood to adulthood in Fragile-X (Fmr1-/y) and contactin-associated (CNTNAP2-/-) knockout mice. Young Fmr1-/y mice (30 days postnatal) presented with a robust hypoconnectivity phenotype in corticocortico and corticostriatal circuits in areas associated with sensory information processing, which was maintained until adulthood. Conversely, only small differences in hippocampal and striatal areas were present during early postnatal development in CNTNAP2-/- mice, while major connectivity deficits in prefrontal and limbic pathways developed between adolescence and adulthood. These findings are supported by viral tracing and electron micrograph approaches and define 2 clearly distinct connectivity endophenotypes within the autism spectrum. We conclude that the genetic background of ASD strongly influences which circuits are most affected, the nature of the phenotype, and the developmental time course of the associated changes.
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Affiliation(s)
- Valerio Zerbi
- Neural Control of Movement Lab, HEST, ETH Zürich, Winterthurerstrasse 190, Zurich, Switzerland
| | - Giovanna D Ielacqua
- Institute for Biomedical Engineering, University and ETH Zurich, Wolfgang-Pauli-Str. 27, Zurich, Switzerland
| | - Marija Markicevic
- Neural Control of Movement Lab, HEST, ETH Zürich, Winterthurerstrasse 190, Zurich, Switzerland
| | - Matthias Georg Haberl
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, USA
| | - Mark H Ellisman
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, USA
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Arjun A-Bhaskaran
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, Bordeaux, France
- University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, Bordeaux, France
| | - Andreas Frick
- INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, Bordeaux, France
- University of Bordeaux, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, Bordeaux, France
| | - Markus Rudin
- Institute for Biomedical Engineering, University and ETH Zurich, Wolfgang-Pauli-Str. 27, Zurich, Switzerland
- Neuroscience Center Zurich, University and ETH Zurich, Winterthurerstrasse 190, Zurich, Switzerland
- Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland
| | - Nicole Wenderoth
- Neural Control of Movement Lab, HEST, ETH Zürich, Winterthurerstrasse 190, Zurich, Switzerland
- Neuroscience Center Zurich, University and ETH Zurich, Winterthurerstrasse 190, Zurich, Switzerland
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25
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Boone CE, Davoudi H, Harrold JB, Foster DJ. Abnormal Sleep Architecture and Hippocampal Circuit Dysfunction in a Mouse Model of Fragile X Syndrome. Neuroscience 2018; 384:275-289. [PMID: 29775702 DOI: 10.1016/j.neuroscience.2018.05.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Revised: 05/03/2018] [Accepted: 05/07/2018] [Indexed: 12/19/2022]
Abstract
Fragile X syndrome (FXS) is the most common heritable cause of intellectual disability and single-gene cause of autism spectrum disorder. The Fmr1 null mouse models much of the human disease including hyperarousal, sensory hypersensitivity, seizure activity, and hippocampus-dependent cognitive impairment. Sleep architecture is disorganized in FXS patients, but has not been examined in Fmr1 knockout (Fmr1-KO) mice. Hippocampal neural activity during sleep, which is implicated in memory processing, also remains uninvestigated in Fmr1-KO mice. We performed in vivo electrophysiological studies of freely behaving Fmr1-KO mice to assess neural activity, in the form of single-unit spiking and local field potential (LFP), within the hippocampal CA1 region during multiple differentiated sleep and wake states. Here, we demonstrate that Fmr1-KO mice exhibited a deficit in rapid eye movement sleep (REM) due to a reduction in the frequency of bouts of REM, consistent with sleep architecture abnormalities of FXS patients. Fmr1-KO CA1 pyramidal cells (CA1-PCs) were hyperactive in all sleep and wake states. Increased low gamma power in CA1 suggests that this hyperactivity was related to increased input to CA1 from CA3. By contrast, slower sharp-wave ripple events (SWRs) in Fmr1-KO mice exhibited longer event duration, slower oscillation frequency, with reduced CA1-PC firing rates during SWRs, yet the incidence rate of SWRs remained intact. These results suggest abnormal neuronal activity in the Fmr1-KO mouse during SWRs, and hyperactivity during other wake and sleep states, with likely adverse consequences for memory processes.
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Affiliation(s)
- Christine E Boone
- Medical Scientist Training Program, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Heydar Davoudi
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, CA, United States
| | - Jon B Harrold
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - David J Foster
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, CA, United States.
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26
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Swanson MR, Wolff JJ, Shen MD, Styner M, Estes A, Gerig G, McKinstry RC, Botteron KN, Piven J, Hazlett HC. Development of White Matter Circuitry in Infants With Fragile X Syndrome. JAMA Psychiatry 2018; 75:505-513. [PMID: 29617515 PMCID: PMC6026861 DOI: 10.1001/jamapsychiatry.2018.0180] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
IMPORTANCE Fragile X syndrome (FXS) is a genetic neurodevelopmental disorder and the most common inherited cause of intellectual disability in males. However, there are no published data on brain development in children with FXS during infancy. OBJECTIVE To characterize the development of white matter at ages 6, 12, and 24 months in infants with FXS compared with that of typically developing controls. DESIGN, SETTING, AND PARTICIPANTS Longitudinal behavioral and brain imaging data were collected at 1 or more time points from 27 infants with FXS and 73 typically developing controls between August 1, 2008, and June 14, 2016, at 2 academic medical centers. Infants in the control group had no first- or second-degree relatives with intellectual or psychiatric disorders, including FXS and autism spectrum disorder. MAIN OUTCOMES AND MEASURES Nineteen major white matter pathways were defined in common atlas space based on anatomically informed methods. Diffusion parameters, including fractional anisotropy, were compared between groups using linear mixed effects modeling. Fiber pathways showing group differences were subsequently examined in association with direct measures of verbal and nonverbal development. RESULTS There were significant differences in the development of 12 of 19 fiber tracts between the 27 infants with FXS (22 boys and 5 girls) and the 73 infants in the control group (46 boys and 27 girls), with lower fractional anisotropy in bilateral subcortical-frontal, occipital-temporal, temporal-frontal, and cerebellar-thalamic pathways, as well as 4 of 6 subdivisions of the corpus callosum. For all 12 of these pathways, there were significant main effects between groups but not for the interaction of age × group, indicating that lower fractional anisotropy was present and stable from age 6 months in infants with FXS. Lower fractional anisotropy values in the uncinate fasciculi were correlated with lower nonverbal developmental quotient in the FXS group (left uncinate, F = 10.06; false discovery rate-corrected P = .03; right uncinate, F = 21.8; P = .004). CONCLUSIONS AND RELEVANCE The results substantiate in human infants the essential role of fragile X gene expression in the early development of white matter. The findings also suggest that the neurodevelopmental effects of FXS are well established at 6 months of age.
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Affiliation(s)
- Meghan R. Swanson
- Carolina Institute for Developmental Disabilities, University of North Carolina at Chapel Hill
| | - Jason J. Wolff
- Department of Educational Psychology, University of Minnesota, Minneapolis
| | - Mark D. Shen
- Department of Psychiatry, University of North Carolina at Chapel Hill
| | - Martin Styner
- Department of Psychiatry, University of North Carolina at Chapel Hill,Department of Computer Science, University of North Carolina at Chapel Hill
| | - Annette Estes
- Department of Speech and Hearing Sciences, University of Washington, Seattle
| | - Guido Gerig
- Department of Computer Science and Engineering, New York University, Brooklyn
| | - Robert C. McKinstry
- Mallinckrodt Institute of Radiology, Washington University in St Louis, St Louis, Missouri
| | - Kelly N. Botteron
- Department of Psychiatry, Washington University in St Louis, St Louis, Missouri,Department of Radiology, Washington University in St Louis, St Louis, Missouri
| | - Joseph Piven
- Department of Psychiatry, University of North Carolina at Chapel Hill
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27
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Abstract
Fragile X syndrome (FXS) is the leading inherited form of intellectual disability and autism spectrum disorder, and patients can present with severe behavioural alterations, including hyperactivity, impulsivity and anxiety, in addition to poor language development and seizures. FXS is a trinucleotide repeat disorder, in which >200 repeats of the CGG motif in FMR1 leads to silencing of the gene and the consequent loss of its product, fragile X mental retardation 1 protein (FMRP). FMRP has a central role in gene expression and regulates the translation of potentially hundreds of mRNAs, many of which are involved in the development and maintenance of neuronal synaptic connections. Indeed, disturbances in neuroplasticity is a key finding in FXS animal models, and an imbalance in inhibitory and excitatory neuronal circuits is believed to underlie many of the clinical manifestations of this disorder. Our knowledge of the proteins that are regulated by FMRP is rapidly growing, and this has led to the identification of multiple targets for therapeutic intervention, some of which have already moved into clinical trials or clinical practice.
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28
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Chyung E, LeBlanc HF, Fallon JR, Akins MR. Fragile X granules are a family of axonal ribonucleoprotein particles with circuit-dependent protein composition and mRNA cargos. J Comp Neurol 2017; 526:96-108. [PMID: 28884477 DOI: 10.1002/cne.24321] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/14/2017] [Accepted: 08/25/2017] [Indexed: 11/08/2022]
Abstract
Local axonal protein synthesis plays a crucial role in the formation and function of neuronal circuits. Understanding the role of this mechanism in specific circuits requires identifying the protein composition and mRNA cargos of the ribonucleoprotein particles (RNPs) that form the substrate for axonal translation. FXGs (Fragile X granules) are axonal RNPs present in a stereotyped subset of mature axons in the intact brain that contain one or more of the Fragile X related (FXR) proteins (FMRP, FXR2P, and FXR1P) along with mRNA and ribosomes. Here we performed a systematic survey of the FXR protein composition and mRNA association of FXGs in the brain. We have identified four FXG types that can be categorized based on their FXR protein complement. All FXGs contain FXR2P, with FMRP and/or FXR1P present in circuit-selective subsets. Individual neuronal cell types predominantly express a single FXG type, with FMRP-containing FXGs the most prevalent in forebrain neurons. All FXG types associate with ribosomes and mRNA, but the specific mRNA cargos are a function of FXG type, brain region and neuron class. Transcripts for β-catenin and its regulator APC associate with a subset of forebrain FXGs. Moreover, both these transcripts can colocalize within individual FXGs, suggesting that the axonal translation of functionally related proteins may be coordinately regulated with high spatiotemporal resolution. Cell type-dependent expression of specific RNP types with distinct mRNA cargos, such as FXGs, presents a potential mechanism for regulating local translation and its output in a circuit-dependent manner.
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Affiliation(s)
- Eunice Chyung
- Department of Neuroscience, Brown University, Providence, Rhode Island, 02912
| | - Hannah F LeBlanc
- Department of Neuroscience, Brown University, Providence, Rhode Island, 02912
| | - Justin R Fallon
- Department of Neuroscience, Brown University, Providence, Rhode Island, 02912
| | - Michael R Akins
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, 19104.,Department of Neurobiology & Anatomy, Drexel University, Philadelphia, Pennsylvania, 19104
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29
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Klein M, van Donkelaar M, Verhoef E, Franke B. Imaging genetics in neurodevelopmental psychopathology. Am J Med Genet B Neuropsychiatr Genet 2017; 174:485-537. [PMID: 29984470 PMCID: PMC7170264 DOI: 10.1002/ajmg.b.32542] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 02/02/2017] [Accepted: 03/10/2017] [Indexed: 01/27/2023]
Abstract
Neurodevelopmental disorders are defined by highly heritable problems during development and brain growth. Attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorders (ASDs), and intellectual disability (ID) are frequent neurodevelopmental disorders, with common comorbidity among them. Imaging genetics studies on the role of disease-linked genetic variants on brain structure and function have been performed to unravel the etiology of these disorders. Here, we reviewed imaging genetics literature on these disorders attempting to understand the mechanisms of individual disorders and their clinical overlap. For ADHD and ASD, we selected replicated candidate genes implicated through common genetic variants. For ID, which is mainly caused by rare variants, we included genes for relatively frequent forms of ID occurring comorbid with ADHD or ASD. We reviewed case-control studies and studies of risk variants in healthy individuals. Imaging genetics studies for ADHD were retrieved for SLC6A3/DAT1, DRD2, DRD4, NOS1, and SLC6A4/5HTT. For ASD, studies on CNTNAP2, MET, OXTR, and SLC6A4/5HTT were found. For ID, we reviewed the genes FMR1, TSC1 and TSC2, NF1, and MECP2. Alterations in brain volume, activity, and connectivity were observed. Several findings were consistent across studies, implicating, for example, SLC6A4/5HTT in brain activation and functional connectivity related to emotion regulation. However, many studies had small sample sizes, and hypothesis-based, brain region-specific studies were common. Results from available studies confirm that imaging genetics can provide insight into the link between genes, disease-related behavior, and the brain. However, the field is still in its early stages, and conclusions about shared mechanisms cannot yet be drawn.
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Affiliation(s)
- Marieke Klein
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Marjolein van Donkelaar
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Ellen Verhoef
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Barbara Franke
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
- Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
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30
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Bruno JL, Hosseini SMH, Saggar M, Quintin EM, Raman MM, Reiss AL. Altered Brain Network Segregation in Fragile X Syndrome Revealed by Structural Connectomics. Cereb Cortex 2017; 27:2249-2259. [PMID: 27009247 DOI: 10.1093/cercor/bhw055] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Fragile X syndrome (FXS), the most common inherited cause of intellectual disability and autism spectrum disorder, is associated with significant behavioral, social, and neurocognitive deficits. Understanding structural brain network topology in FXS provides an important link between neurobiological and behavioral/cognitive symptoms of this disorder. We investigated the connectome via whole-brain structural networks created from group-level morphological correlations. Participants included 100 individuals: 50 with FXS and 50 with typical development, age 11-23 years. Results indicated alterations in topological properties of structural brain networks in individuals with FXS. Significantly reduced small-world index indicates a shift in the balance between network segregation and integration and significantly reduced clustering coefficient suggests that reduced local segregation shifted this balance. Caudate and amygdala were less interactive in the FXS network further highlighting the importance of subcortical region alterations in the neurobiological signature of FXS. Modularity analysis indicates that FXS and typically developing groups' networks decompose into different sets of interconnected sub networks, potentially indicative of aberrant local interconnectivity in individuals with FXS. These findings advance our understanding of the effects of fragile X mental retardation protein on large-scale brain networks and could be used to develop a connectome-level biological signature for FXS.
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Affiliation(s)
- Jennifer Lynn Bruno
- Department of Psychiatry, Center for Interdisciplinary Brain Sciences Research, Stanford, CA 94305-5795, USA
| | - S M Hadi Hosseini
- Department of Psychiatry, Center for Interdisciplinary Brain Sciences Research, Stanford, CA 94305-5795, USA
| | - Manish Saggar
- Department of Psychiatry, Center for Interdisciplinary Brain Sciences Research, Stanford, CA 94305-5795, USA
| | - Eve-Marie Quintin
- School and Applied Child Psychology Program, McGill University, Montreal, QC, CanadaH3A 1Y2
| | - Mira Michelle Raman
- Department of Psychiatry, Center for Interdisciplinary Brain Sciences Research, Stanford, CA 94305-5795, USA
| | - Allan L Reiss
- Department of Psychiatry, Center for Interdisciplinary Brain Sciences Research, Stanford, CA 94305-5795, USA.,Department of Radiology.,Department of Pediatrics, Stanford University, Stanford, CA 94305, USA
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31
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Havlík M. From Anomalies to Essential Scientific Revolution? Intrinsic Brain Activity in the Light of Kuhn's Philosophy of Science. Front Syst Neurosci 2017; 11:7. [PMID: 28293181 PMCID: PMC5328955 DOI: 10.3389/fnsys.2017.00007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 02/13/2017] [Indexed: 01/04/2023] Open
Abstract
The first step toward a modern understanding of fMRI resting brain activity was made by Bharat Biswal in 1995. This surprising, and at first rejected, discovery is now associated with many resting state networks, notably the famous default mode network (DMN). Resting state activity and DMN significantly reassessed our traditional beliefs and conventions about the functioning of the brain. For the majority of the twentieth century, neuroscientists assumed that the brain is mainly the "reactive engine" to the environment operating mostly through stimulation. This "reactive convention" was very influential and convenient for the goals of twentieth century neuroscience-non-invasive functional localization based on stimulation. Largely unchallenged, "reactive convention" determined the direction of scientific research for a long time and became the "reactive paradigm" of the twentieth century. Resting state activity brought knowledge that was quite different of the "reactive paradigm." Current research of the DMN, probably the best known resting state network, leads to entirely new observations and conclusions, which were not achievable from the perspective of the "reactive paradigm." This shift from reactive activity to resting state activity of the brain is accompanied by an important question: "Can resting state activity be considered a scientific revolution and the new paradigm of neuroscience, or is it only significant for one branch of neuroscience, such as fMRI?"
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Affiliation(s)
- Marek Havlík
- Department of Applied Neurosciences and Brain Imaging, National Institute of Mental HealthKlecany, Czechia
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32
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Fung LK, Reiss AL. Moving Toward Integrative, Multidimensional Research in Modern Psychiatry: Lessons Learned From Fragile X Syndrome. Biol Psychiatry 2016; 80:100-111. [PMID: 26868443 PMCID: PMC4912939 DOI: 10.1016/j.biopsych.2015.12.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 12/14/2015] [Accepted: 12/15/2015] [Indexed: 10/22/2022]
Abstract
The field of psychiatry is approaching a major inflection point. The basic science behind cognition, emotion, behavior, and social processes has been advancing rapidly in the past 20 years. However, clinical research supporting the classification system in psychiatry has not kept up with these scientific advances. To begin organizing the basic science of psychiatry in a comprehensive manner, we begin by selecting fragile X syndrome, a neurogenetic disease with cognitive-behavioral manifestations, to illustrate key concepts in an integrative, multidimensional model. Specifically, we describe key genetic and molecular mechanisms (e.g., gamma-aminobutyric acidergic dysfunction and metabotropic glutamate receptor 5-associated long-term depression) relevant to the pathophysiology of fragile X syndrome as well as neural correlates of cognitive-behavioral symptoms. We then describe what we have learned from fragile X syndrome that may be applicable to other psychiatric disorders. We conclude this review by discussing current and future opportunities in diagnosing and treating psychiatric diseases.
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Affiliation(s)
- Lawrence K. Fung
- Division of Child & Adolescent Psychiatry, Department of Psychiatry & Behavioral Sciences, Stanford University, Stanford, CA
| | - Allan L. Reiss
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry & Behavioral Sciences, Stanford University, Stanford, CA
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33
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Hall SS, Dougherty RF, Reiss AL. Profiles of aberrant white matter microstructure in fragile X syndrome. Neuroimage Clin 2016; 11:133-138. [PMID: 26937381 PMCID: PMC4753809 DOI: 10.1016/j.nicl.2016.01.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 01/09/2016] [Accepted: 01/12/2016] [Indexed: 01/28/2023]
Abstract
Previous studies attempting to quantify white matter (WM) microstructure in individuals with fragile X syndrome (FXS) have produced inconsistent findings, most likely due to the various control groups employed, differing analysis methods, and failure to examine for potential motion artifact. In addition, analyses have heretofore lacked sufficient specificity to provide regional information. In this study, we used Automated Fiber-tract Quantification (AFQ) to identify specific regions of aberrant WM microstructure along WM tracts in patients with FXS that differed from controls who were matched on age, IQ and degree of autistic symptoms. Participants were 20 patients with FXS, aged 10 to 23 years, and 20 matched controls. Using Automated Fiber-tract Quantification (AFQ), we created Tract Profiles of fractional anisotropy and mean diffusivity along 18 major WM fascicles. We found that fractional anisotropy was significantly increased in the left and right inferior longitudinal fasciculus (ILF), right uncinate fasciculus, and left cingulum hippocampus in individuals with FXS compared to controls. Conversely, mean diffusivity was significantly decreased in the right ILF in patients with FXS compared to controls. Age was significantly negatively associated with MD values across both groups in 11 tracts. Taken together, these findings indicate that FXS results in abnormal WM microstructure in specific regions of the ILF and uncinate fasciculus, most likely caused by inefficient synaptic pruning as a result of decreased or absent Fragile X Mental Retardation Protein (FMRP). Longitudinal studies are needed to confirm these findings.
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Affiliation(s)
- Scott S Hall
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, United States.
| | - Robert F Dougherty
- Center for Neurobiological Imaging (CNI), Stanford University, Stanford, CA, United States
| | - Allan L Reiss
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, United States
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Schroeder MP, Weiss C, Procissi D, Disterhoft JF, Wang L. Intrinsic connectivity of neural networks in the awake rabbit. Neuroimage 2016; 129:260-267. [PMID: 26774609 DOI: 10.1016/j.neuroimage.2016.01.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 12/04/2015] [Accepted: 01/05/2016] [Indexed: 12/26/2022] Open
Abstract
The way in which the brain is functionally connected into different networks has emerged as an important research topic in order to understand normal neural processing and signaling. Since some experimental manipulations are difficult or unethical to perform in humans, animal models are better suited to investigate this topic. Rabbits are a species that can undergo MRI scanning in an awake and conscious state with minimal preparation and habituation. In this study, we characterized the intrinsic functional networks of the resting New Zealand White rabbit brain using BOLD fMRI data. Group independent component analysis revealed seven networks similar to those previously found in humans, non-human primates and/or rodents including the hippocampus, default mode, cerebellum, thalamus, and visual, somatosensory, and parietal cortices. For the first time, the intrinsic functional networks of the resting rabbit brain have been elucidated demonstrating the rabbit's applicability as a translational animal model. Without the confounding effects of anesthetics or sedatives, future experiments may employ rabbits to understand changes in neural connectivity and brain functioning as a result of experimental manipulation (e.g., temporary or permanent network disruption, learning-related changes, and drug administration).
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Affiliation(s)
- Matthew P Schroeder
- Department of Physiology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Avenue, Ward Building 7-140, Chicago, Illinois 60611, USA
| | - Craig Weiss
- Department of Physiology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Avenue, Ward Building 7-140, Chicago, Illinois 60611, USA
| | - Daniel Procissi
- Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 North Michigan Avenue, Suite 1600, Chicago, IL 60611, USA
| | - John F Disterhoft
- Department of Physiology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Avenue, Ward Building 7-140, Chicago, Illinois 60611, USA
| | - Lei Wang
- Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 North Michigan Avenue, Suite 1600, Chicago, IL 60611, USA
- Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, 710 N. Lake Shore Drive, Abbott Hall 1322, Chicago, IL 60611, USA
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The cognitive developmental profile associated with fragile X syndrome: A longitudinal investigation of cognitive strengths and weaknesses through childhood and adolescence. Dev Psychopathol 2015; 28:1457-1469. [PMID: 26648140 DOI: 10.1017/s0954579415001200] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Few studies have investigated developmental strengths and weaknesses within the cognitive profile of children and adolescents with fragile X syndrome (FXS), a single-gene cause of inherited intellectual impairment. With a prospective longitudinal design and using normalized raw scores (Z scores) to circumvent floor effects, we measured cognitive functioning of 184 children and adolescents with FXS (ages 6 to 16) using the Wechsler Scale of Intelligence for Children on one to three occasions for each participant. Participants with FXS received lower raw scores relative to the Wechsler Scale of Intelligence for Children normative sample across the developmental period. Verbal comprehension, perceptual organization, and processing speed Z scores were marked by a widening gap from the normative sample, while freedom from distractibility Z scores showed a narrowing gap. Key findings include a relative strength for verbal skills in comparison with visuospatial-constructive skills arising in adolescence and a discrepancy between working memory (weakness) and processing speed (strength) in childhood that diminishes in adolescence. Results suggest that the cognitive profile associated with FXS develops dynamically from childhood to adolescence. Findings are discussed within the context of aberrant brain morphology in childhood and maturation in adolescence. We argue that assessing disorder-specific cognitive developmental profiles will benefit future disorder-specific treatment research.
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Haberl MG, Zerbi V, Veltien A, Ginger M, Heerschap A, Frick A. Structural-functional connectivity deficits of neocortical circuits in the Fmr1 (-/y) mouse model of autism. SCIENCE ADVANCES 2015; 1:e1500775. [PMID: 26702437 PMCID: PMC4681325 DOI: 10.1126/sciadv.1500775] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 10/13/2015] [Indexed: 05/13/2023]
Abstract
Fragile X syndrome (FXS), the most common inherited form of intellectual disability disorder and a frequent cause of autism spectrum disorder (ASD), is characterized by a high prevalence of sensory symptoms. Perturbations in the anatomical connectivity of neocortical circuits resulting in their functional defects have been hypothesized to contribute to the underlying etiology of these disorders. We tested this idea by probing alterations in the functional and structural connectivity of both local and long-ranging neocortical circuits in the Fmr1 (-/y) mouse model of FXS. To achieve this, we combined in vivo ultrahigh-field diffusion tensor magnetic resonance imaging (MRI), functional MRI, and viral tracing approaches in adult mice. Our results show an anatomical hyperconnectivity phenotype for the primary visual cortex (V1), but a disproportional low connectivity of V1 with other neocortical regions. These structural data are supported by defects in the structural integrity of the subcortical white matter in the anterior and posterior forebrain. These anatomical alterations might contribute to the observed functional decoupling across neocortical regions. We therefore identify FXS as a "connectopathy," providing a translational model for understanding sensory processing defects and functional decoupling of neocortical areas in FXS and ASD.
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Affiliation(s)
- Matthias G. Haberl
- INSERM, Neurocentre Magendie, Physiopathologie de la plasticité neuronale, U862, 33077 Bordeaux, France
- University of Bordeaux, Neurocentre Magendie, Physiopathologie de la plasticité neuronale, U862, 33076 Bordeaux, France
- Institute of NeuroInformatics, University of Zurich, 8057 Zurich, Switzerland
| | - Valerio Zerbi
- Biomedical MR Research Group, Department of Radiology and Nuclear Medicine, Radboud University Medical Center, 6500 Nijmegen, Netherlands
| | - Andor Veltien
- Biomedical MR Research Group, Department of Radiology and Nuclear Medicine, Radboud University Medical Center, 6500 Nijmegen, Netherlands
| | - Melanie Ginger
- INSERM, Neurocentre Magendie, Physiopathologie de la plasticité neuronale, U862, 33077 Bordeaux, France
- University of Bordeaux, Neurocentre Magendie, Physiopathologie de la plasticité neuronale, U862, 33076 Bordeaux, France
| | - Arend Heerschap
- Biomedical MR Research Group, Department of Radiology and Nuclear Medicine, Radboud University Medical Center, 6500 Nijmegen, Netherlands
| | - Andreas Frick
- INSERM, Neurocentre Magendie, Physiopathologie de la plasticité neuronale, U862, 33077 Bordeaux, France
- University of Bordeaux, Neurocentre Magendie, Physiopathologie de la plasticité neuronale, U862, 33076 Bordeaux, France
- Corresponding author. E-mail:
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Klabunde M, Saggar M, Hustyi KM, Kelley RG, Reiss AL, Hall SS. Examining the neural correlates of emergent equivalence relations in fragile X syndrome. Psychiatry Res 2015; 233:373-9. [PMID: 26250852 PMCID: PMC4555007 DOI: 10.1016/j.pscychresns.2015.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 03/23/2015] [Accepted: 06/25/2015] [Indexed: 10/23/2022]
Abstract
The neural mechanisms underlying the formation of stimulus equivalence relations are poorly understood, particularly in individuals with specific learning impairments. As part of a larger study, we used functional magnetic resonance imaging (fMRI) while participants with fragile X syndrome (FXS), and age- and IQ-matched controls with intellectual disability, were required to form new equivalence relations in the scanner. Following intensive training on matching fractions to pie charts (A=B relations) and pie charts to decimals (B=C relations) outside the scanner over a 2-day period, participants were tested on the trained (A=B, B=C) relations, as well as emergent symmetry (i.e., B=A and C=B) and transitivity/equivalence (i.e., A=C and C=A) relations inside the scanner. Eight participants with FXS (6 female, 2 male) and 10 controls, aged 10-23 years, were able to obtain at least 66.7% correct on the trained relations in the scanner and were included in the fMRI analyses. Across both groups, results showed that the emergence of symmetry relations was correlated with increased brain activation in the left inferior parietal lobule, left postcentral gyrus, and left insula, broadly supporting previous investigations of stimulus equivalence research in neurotypical populations. On the test of emergent transitivity/equivalence relations, activation was significantly greater in individuals with FXS compared with controls in the right middle temporal gyrus, left superior frontal gyrus and left precuneus. These data indicate that neural execution was significantly different in individuals with FXS than in age- and IQ-matched controls during stimulus equivalence formation. Further research concerning how gene-brain-behavior interactions may influence the emergence of stimulus equivalence in individuals with intellectual disabilities is needed.
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Affiliation(s)
| | | | | | | | | | - Scott S. Hall
- Corresponding author: Center for Interdisciplinary Brain Sciences Research, Room 1365, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 401 Quarry Road, Stanford, CA, USA. Tel.: +1 (650) 498 4799,
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Padula MC, Schaer M, Scariati E, Schneider M, Van De Ville D, Debbané M, Eliez S. Structural and functional connectivity in the default mode network in 22q11.2 deletion syndrome. J Neurodev Disord 2015; 7:23. [PMID: 26236404 PMCID: PMC4522079 DOI: 10.1186/s11689-015-9120-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Accepted: 06/25/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The neural endophenotype associated with 22q11.2 deletion syndrome (22q11DS) includes deviant cortical development and alterations in brain connectivity. Resting-state functional magnetic resonance imaging (fMRI) findings also reported disconnectivity within the default mode network (DMN). In this study, we explored the relationship between functional and structural DMN connectivity and their changes with age in patients with 22q11DS in comparison to control participants. Given previous evidence of an association between DMN disconnectivity and the manifestation of psychotic symptoms, we further investigated this relationship in our group of patients with 22q11DS. METHODS T1-weighted, diffusion, and resting-state fMRI scans were acquired from 41 patients with 22q11DS and 43 control participants aged 6 to 28 years. A data-driven approach based on independent component analysis (ICA) was used to identify the DMN and to define regions of interest for the structural and functional connectivity analysis. Prodromal psychotic symptoms were assessed in adolescents and adults using the positive symptom scores of the Structured Interview of Prodromal Syndromes (SIPS). Connectivity measures were compared between groups and correlated with age. Repeating the between-group analysis in three different age bins further assessed the presence of age-related alterations in DMN connectivity. Structural and functional connectivity measures were then correlated with the SIPS scores. RESULTS A simultaneous reduction of functional and structural connectivity between core medial nodes of the DMN was observed. Furthermore, structural connectivity measures significantly increased with age in the control group but not in patients with 22q11DS, suggesting the presence of an age-related alteration of the DMN structural connections. No correlations were found between the DMN disconnectivity and expression of prodromal symptoms in 22q11DS. CONCLUSIONS These findings indicate the presence of functional and structural DMN disconnectivity in 22q11DS and that patients with 22q11DS fail to develop normal structural connections between medial DMN nodes. This suggests the presence of altered neurodevelopmental trajectories in 22q11DS.
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Affiliation(s)
- Maria Carmela Padula
- Office Médico-Pédagogique, Department of Psychiatry, University of Geneva, Rue David-Dufour 1, Case Postale 50, 1211 Genève 8, Switzerland
| | - Marie Schaer
- Office Médico-Pédagogique, Department of Psychiatry, University of Geneva, Rue David-Dufour 1, Case Postale 50, 1211 Genève 8, Switzerland ; Stanford Cognitive and Systems Neuroscience Laboratory, Stanford University, Stanford, CA USA
| | - Elisa Scariati
- Office Médico-Pédagogique, Department of Psychiatry, University of Geneva, Rue David-Dufour 1, Case Postale 50, 1211 Genève 8, Switzerland
| | - Maude Schneider
- Office Médico-Pédagogique, Department of Psychiatry, University of Geneva, Rue David-Dufour 1, Case Postale 50, 1211 Genève 8, Switzerland
| | - Dimitri Van De Ville
- Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland ; Medical Image Processing Lab, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Martin Debbané
- Office Médico-Pédagogique, Department of Psychiatry, University of Geneva, Rue David-Dufour 1, Case Postale 50, 1211 Genève 8, Switzerland ; Adolescence Clinical Psychology Research Unit, Faculty of Psychology and Educational Sciences, Geneva, Switzerland ; Research Department of Clinical, Educational and Health Psychology, University College London, London, U K
| | - Stephan Eliez
- Office Médico-Pédagogique, Department of Psychiatry, University of Geneva, Rue David-Dufour 1, Case Postale 50, 1211 Genève 8, Switzerland ; Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
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Estimating individual contribution from group-based structural correlation networks. Neuroimage 2015; 120:274-84. [PMID: 26162553 DOI: 10.1016/j.neuroimage.2015.07.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 06/16/2015] [Accepted: 07/03/2015] [Indexed: 12/22/2022] Open
Abstract
Coordinated variations in brain morphology (e.g., cortical thickness) across individuals have been widely used to infer large-scale population brain networks. These structural correlation networks (SCNs) have been shown to reflect synchronized maturational changes in connected brain regions. Further, evidence suggests that SCNs, to some extent, reflect both anatomical and functional connectivity and hence provide a complementary measure of brain connectivity in addition to diffusion weighted networks and resting-state functional networks. Although widely used to study between-group differences in network properties, SCNs are inferred only at the group-level using brain morphology data from a set of participants, thereby not providing any knowledge regarding how the observed differences in SCNs are associated with individual behavioral, cognitive and disorder states. In the present study, we introduce two novel distance-based approaches to extract information regarding individual differences from the group-level SCNs. We applied the proposed approaches to a moderately large dataset (n=100) consisting of individuals with fragile X syndrome (FXS; n=50) and age-matched typically developing individuals (TD; n=50). We tested the stability of proposed approaches using permutation analysis. Lastly, to test the efficacy of our method, individual contributions extracted from the group-level SCNs were examined for associations with intelligence scores and genetic data. The extracted individual contributions were stable and were significantly related to both genetic and intelligence estimates, in both typically developing individuals and participants with FXS. We anticipate that the approaches developed in this work could be used as a putative biomarker for altered connectivity in individuals with neurodevelopmental disorders.
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Frolli A, Piscopo S, Conson M. Developmental changes in cognitive and behavioural functioning of adolescents with fragile-X syndrome. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 2015; 59:613-621. [PMID: 25160119 DOI: 10.1111/jir.12165] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/25/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND Individuals with fragile-X syndrome exhibit developmental delay, hyperexcitation and social anxiety; they also show lack of attention and hyperactivity. Few studies have investigated whether levels of functioning change with increasing age. Here, we explored developmental changes across adolescence in the cognitive and behavioural profile of individuals with fragile-X syndrome. To this scope, we assessed intellectual functioning, adaptive behaviour, autistic symptomatology, behavioural problems (e.g. hyperactivity/lack of attention) and strengths (prosocial behaviours). METHOD Thirty-six participants underwent standardised outcome measures (i.e. the Wechsler Intelligence Scales-Revised, the Childhood Autism Rating Scale, the Vineland Adaptive Behavior Scales, and the Strengths and Difficulty Questionnaire) in three time points (Time 1: 9-11; Time 2: 11-13, and Time 3: 13-15 years). RESULTS Verbal IQ improved across time, whereas Nonverbal IQ declined and Full Scale IQ was quite unchanged. Autism ratings decreased; communication and social aspects of adaptive behaviour also enhanced. Finally, elevated levels of hyperactivity/lack of attention at Time 1 significantly improved across the three time points, whereas emotional symptoms, behavioural difficulties, problems with peers and prosocial behaviours remained stable over time. CONCLUSION These findings revealed specific developmental changes in cognitive and behavioural functioning of individuals with fragile-X syndrome, likely related to a progressive maturation of brain systems devoted to attentional control.
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Affiliation(s)
- A Frolli
- Department of Psychology, Second University of Naples, Naples, Italy
| | - S Piscopo
- Laboratory of Animal Physiology and Evolution, Stazione Zoologica Anton Dohrn, Naples, Italy
| | - M Conson
- Department of Psychology, Second University of Naples, Naples, Italy
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41
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Scerif G, Baker K. Annual research review: Rare genotypes and childhood psychopathology--uncovering diverse developmental mechanisms of ADHD risk. J Child Psychol Psychiatry 2015; 56:251-73. [PMID: 25494546 DOI: 10.1111/jcpp.12374] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/10/2014] [Indexed: 01/25/2023]
Abstract
BACKGROUND Through the increased availability and sophistication of genetic testing, it is now possible to identify causal diagnoses in a growing proportion of children with neurodevelopmental disorders. In addition to developmental delay and intellectual disability, many genetic disorders are associated with high risks of psychopathology, which curtail the wellbeing of affected individuals and their families. Beyond the identification of significant clinical needs, understanding the diverse pathways from rare genetic mutations to cognitive dysfunction and emotional-behavioural disturbance has theoretical and practical utility. METHODS We overview (based on a strategic search of the literature) the state-of-the-art on causal mechanisms leading to one of the most common childhood behavioural diagnoses - attention deficit hyperactivity disorder (ADHD) - in the context of specific genetic disorders. We focus on new insights emerging from the mapping of causal pathways from identified genetic differences to neuronal biology, brain abnormalities, cognitive processing differences and ultimately behavioural symptoms of ADHD. FINDINGS First, ADHD research in the context of rare genotypes highlights the complexity of multilevel mechanisms contributing to psychopathology risk. Second, comparisons between genetic disorders associated with similar psychopathology risks can elucidate convergent or distinct mechanisms at each level of analysis, which may inform therapeutic interventions and prognosis. Third, genetic disorders provide an unparalleled opportunity to observe dynamic developmental interactions between neurocognitive risk and behavioural symptoms. Fourth, variation in expression of psychopathology risk within each genetic disorder points to putative moderating and protective factors within the genome and the environment. CONCLUSION A common imperative emerging within psychopathology research is the need to investigate mechanistically how developmental trajectories converge or diverge between and within genotype-defined groups. Crucially, as genetic predispositions modify interaction dynamics from the outset, longitudinal research is required to understand the multi-level developmental processes that mediate symptom evolution.
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Affiliation(s)
- Gaia Scerif
- Department of Experimental Psychology, University of Oxford, Oxford, UK
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La Fata G, Gärtner A, Domínguez-Iturza N, Dresselaers T, Dawitz J, Poorthuis RB, Averna M, Himmelreich U, Meredith RM, Achsel T, Dotti CG, Bagni C. FMRP regulates multipolar to bipolar transition affecting neuronal migration and cortical circuitry. Nat Neurosci 2014; 17:1693-700. [PMID: 25402856 DOI: 10.1038/nn.3870] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 10/16/2014] [Indexed: 12/20/2022]
Abstract
Deficiencies in fragile X mental retardation protein (FMRP) are the most common cause of inherited intellectual disability, fragile X syndrome (FXS), with symptoms manifesting during infancy and early childhood. Using a mouse model for FXS, we found that Fmrp regulates the positioning of neurons in the cortical plate during embryonic development, affecting their multipolar-to-bipolar transition (MBT). We identified N-cadherin, which is crucial for MBT, as an Fmrp-regulated target in embryonic brain. Furthermore, spontaneous network activity and high-resolution brain imaging revealed defects in the establishment of neuronal networks at very early developmental stages, further confirmed by an unbalanced excitatory and inhibitory network. Finally, reintroduction of Fmrp or N-cadherin in the embryo normalized early postnatal neuron activity. Our findings highlight the critical role of Fmrp in the developing cerebral cortex and might explain some of the clinical features observed in patients with FXS, such as alterations in synaptic communication and neuronal network connectivity.
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Affiliation(s)
- Giorgio La Fata
- 1] VIB Center for the Biology of Disease, KU Leuven, Leuven, Belgium. [2] Center for Human Genetics and Leuven Institute for Neurodegenerative Diseases (LIND), KU Leuven, Leuven, Belgium
| | - Annette Gärtner
- 1] VIB Center for the Biology of Disease, KU Leuven, Leuven, Belgium. [2] Center for Human Genetics and Leuven Institute for Neurodegenerative Diseases (LIND), KU Leuven, Leuven, Belgium
| | - Nuria Domínguez-Iturza
- 1] VIB Center for the Biology of Disease, KU Leuven, Leuven, Belgium. [2] Center for Human Genetics and Leuven Institute for Neurodegenerative Diseases (LIND), KU Leuven, Leuven, Belgium
| | | | - Julia Dawitz
- Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, the Netherlands
| | - Rogier B Poorthuis
- Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, the Netherlands
| | - Michele Averna
- 1] VIB Center for the Biology of Disease, KU Leuven, Leuven, Belgium. [2] Center for Human Genetics and Leuven Institute for Neurodegenerative Diseases (LIND), KU Leuven, Leuven, Belgium
| | | | - Rhiannon M Meredith
- Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, the Netherlands
| | - Tilmann Achsel
- 1] VIB Center for the Biology of Disease, KU Leuven, Leuven, Belgium. [2] Center for Human Genetics and Leuven Institute for Neurodegenerative Diseases (LIND), KU Leuven, Leuven, Belgium
| | - Carlos G Dotti
- 1] VIB Center for the Biology of Disease, KU Leuven, Leuven, Belgium. [2] Center for Human Genetics and Leuven Institute for Neurodegenerative Diseases (LIND), KU Leuven, Leuven, Belgium. [3] Centro de Biología Molecular Severo Ochoa, Campus de la Universidad Autónoma de Madrid, Spain
| | - Claudia Bagni
- 1] VIB Center for the Biology of Disease, KU Leuven, Leuven, Belgium. [2] Center for Human Genetics and Leuven Institute for Neurodegenerative Diseases (LIND), KU Leuven, Leuven, Belgium. [3] Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
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Luckhardt C, Jarczok TA, Bender S. Elucidating the neurophysiological underpinnings of autism spectrum disorder: new developments. J Neural Transm (Vienna) 2014; 121:1129-44. [PMID: 25059455 DOI: 10.1007/s00702-014-1265-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 06/19/2014] [Indexed: 12/11/2022]
Abstract
The study of neurophysiological approaches together with rare and common risk factors for Autism Spectrum Disorder (ASD) allows elucidating the specific underlying neurobiology of ASD. Whereas most neurophysiologically based research in ASD to date has focussed on case-control differences based on the DSM- or ICD-based categorical ASD diagnosis, more recent studies have aimed at studying genetically and/or neurophysiologically defined homogeneous ASD subgroups for specific neuronal biomarkers. This review addresses the neurophysiological investigation of ASD by evoked and event-related potentials, by EEG/MEG connectivity measures such as coherence, and transcranial magnetic stimulation. As an example of classical neurophysiological studies in ASD, we report event-related potential studies which have illustrated which brain areas and processing stages are affected in the visual perception of socially relevant stimuli. However, a paradigm shift has taken place in recent years focussing on how these findings can be tracked down to basic neuronal functions such as deficits in cortico-cortical connectivity and the interaction between brain areas. Disconnectivity, for example, can again be related to genetically induced shifts in the excitation/inhibition balance. Genetic causes of ASD may be grouped by their effects on the brain's system level to identify ASD subgroups which respond differentially to therapeutic interventions.
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Affiliation(s)
- C Luckhardt
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, JW Goethe University Frankfurt, Deutschordenstraße 50, 60528, Frankfurt am Main, Germany,
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Colvin SM, Kwan KY. Dysregulated nitric oxide signaling as a candidate mechanism of fragile X syndrome and other neuropsychiatric disorders. Front Genet 2014; 5:239. [PMID: 25101118 PMCID: PMC4105824 DOI: 10.3389/fgene.2014.00239] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 07/03/2014] [Indexed: 12/31/2022] Open
Abstract
A mechanistic understanding of the pathophysiology underpinning psychiatric disorders is essential for the development of targeted molecular therapies. For fragile X syndrome (FXS), recent mechanistic studies have been focused on the metabotropic glutamate receptor (mGluR) signaling pathway. This line of research has led to the discovery of promising candidate drugs currently undergoing various phases of clinical trial, and represents a model of how biological insights can inform therapeutic strategies in neurodevelopmental disorders. Although mGluR signaling is a key mechanism at which targeted treatments can be directed, it is likely to be one of many mechanisms contributing to FXS. A more complete understanding of the molecular and neural underpinnings of the disorder is expected to inform additional therapeutic strategies. Alterations in the assembly of neural circuits in the neocortex have been recently implicated in genetic studies of autism and schizophrenia, and may also contribute to FXS. In this review, we explore dysregulated nitric oxide signaling in the developing neocortex as a novel candidate mechanism of FXS. This possibility stems from our previous work demonstrating that neuronal nitric oxide synthase 1 (NOS1 or nNOS) is regulated by the FXS protein FMRP in the mid-fetal human neocortex. Remarkably, in the mid-late fetal and early postnatal neocortex of human FXS patients, NOS1 expression is severely diminished. Given the role of nitric oxide in diverse neural processes, including synaptic development and plasticity, the loss of NOS1 in FXS may contribute to the etiology of the disorder. Here, we outline the genetic and neurobiological data that implicate neocortical dysfunction in FXS, review the evidence supporting dysregulated nitric oxide signaling in the developing FXS neocortex and its contribution to the disorder, and discuss the implications for targeting nitric oxide signaling in the treatment of FXS and other psychiatric illnesses.
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Affiliation(s)
- Steven M Colvin
- Department of Human Genetics - The Molecular and Behavioral Neuroscience Institute, University of Michigan Medical School Ann Arbor, MI, USA
| | - Kenneth Y Kwan
- Department of Human Genetics - The Molecular and Behavioral Neuroscience Institute, University of Michigan Medical School Ann Arbor, MI, USA
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Cook IA, Hunter AM, Korb AS, Leuchter AF. Do prefrontal midline electrodes provide unique neurophysiologic information in Major Depressive Disorder? J Psychiatr Res 2014; 53:69-75. [PMID: 24630467 PMCID: PMC6333308 DOI: 10.1016/j.jpsychires.2014.01.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 12/21/2013] [Accepted: 01/30/2014] [Indexed: 02/01/2023]
Abstract
Brain oscillatory activity from the midline prefrontal region has been shown to reflect brain dysfunction in subjects with Major Depressive Disorder (MDD). It is not known, however, whether electrodes from this area provide unique information about brain function in MDD. We examined a set of midline sites and two other prefrontal locations for detecting cerebral activity differences between subjects with MDD and healthy controls. Resting awake quantitative EEG (qEEG) data were recorded from 168 subjects: 47 never-depressed adults and 121 with a current major depressive episode. Individual midline electrodes (Fpz, Fz, Cz, Pz, and Oz) and prefrontal electrodes outside the hairline (Fp1, Fp2) were examined with absolute and relative power and cordance in the theta band. We found that MDD subjects exhibited higher values of cordance (p = 0.0066) at Fpz than controls; no significant differences were found at other locations, and power measures showed trend-level differences. Depressed adults showed higher midline cordance than did never-depressed subjects at the most-anterior midline channel. Salient abnormalities in MDD may be detectable by focusing on the prefrontal midline region, and EEG metrics from focused electrode arrays may offer clinical practicality for clinical monitoring.
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Affiliation(s)
- Ian A Cook
- UCLA Depression Research & Clinic Program, Semel Institute for Neuroscience and Human Behavior at UCLA, Brain Research Institute, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, United States; Laboratory of Brain, Behavior, and Pharmacology, Semel Institute for Neuroscience and Human Behavior at UCLA, Brain Research Institute, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, United States; Department of Bioengineering, Henry Samueli School of Engineering & Applied Science, Los Angeles, CA, United States.
| | - Aimee M Hunter
- UCLA Depression Research & Clinic Program, Semel Institute for Neuroscience and Human Behavior at UCLA, Brain Research Institute, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, United States; Laboratory of Brain, Behavior, and Pharmacology, Semel Institute for Neuroscience and Human Behavior at UCLA, Brain Research Institute, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, United States
| | - Alexander S Korb
- UCLA Depression Research & Clinic Program, Semel Institute for Neuroscience and Human Behavior at UCLA, Brain Research Institute, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, United States; Laboratory of Brain, Behavior, and Pharmacology, Semel Institute for Neuroscience and Human Behavior at UCLA, Brain Research Institute, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, United States
| | - Andrew F Leuchter
- UCLA Depression Research & Clinic Program, Semel Institute for Neuroscience and Human Behavior at UCLA, Brain Research Institute, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, United States; Laboratory of Brain, Behavior, and Pharmacology, Semel Institute for Neuroscience and Human Behavior at UCLA, Brain Research Institute, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, United States
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Degraded speech sound processing in a rat model of fragile X syndrome. Brain Res 2014; 1564:72-84. [PMID: 24713347 DOI: 10.1016/j.brainres.2014.03.049] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 03/29/2014] [Accepted: 03/31/2014] [Indexed: 12/29/2022]
Abstract
Fragile X syndrome is the most common inherited form of intellectual disability and the leading genetic cause of autism. Impaired phonological processing in fragile X syndrome interferes with the development of language skills. Although auditory cortex responses are known to be abnormal in fragile X syndrome, it is not clear how these differences impact speech sound processing. This study provides the first evidence that the cortical representation of speech sounds is impaired in Fmr1 knockout rats, despite normal speech discrimination behavior. Evoked potentials and spiking activity in response to speech sounds, noise burst trains, and tones were significantly degraded in primary auditory cortex, anterior auditory field and the ventral auditory field. Neurometric analysis of speech evoked activity using a pattern classifier confirmed that activity in these fields contains significantly less information about speech sound identity in Fmr1 knockout rats compared to control rats. Responses were normal in the posterior auditory field, which is associated with sound localization. The greatest impairment was observed in the ventral auditory field, which is related to emotional regulation. Dysfunction in the ventral auditory field may contribute to poor emotional regulation in fragile X syndrome and may help explain the observation that later auditory evoked responses are more disturbed in fragile X syndrome compared to earlier responses. Rodent models of fragile X syndrome are likely to prove useful for understanding the biological basis of fragile X syndrome and for testing candidate therapies.
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