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Autism, heparan sulfate and potential interventions. Exp Neurol 2022; 353:114050. [DOI: 10.1016/j.expneurol.2022.114050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 02/25/2022] [Accepted: 03/13/2022] [Indexed: 11/16/2022]
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2
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Bicker F, Nardi L, Maier J, Vasic V, Schmeisser MJ. Criss-crossing autism spectrum disorder and adult neurogenesis. J Neurochem 2021; 159:452-478. [PMID: 34478569 DOI: 10.1111/jnc.15501] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 08/05/2021] [Accepted: 08/28/2021] [Indexed: 12/19/2022]
Abstract
Autism spectrum disorder (ASD) comprises a group of multifactorial neurodevelopmental disorders primarily characterized by deficits in social interaction and repetitive behavior. Although the onset is typically in early childhood, ASD poses a lifelong challenge for both patients and caretakers. Adult neurogenesis (AN) is the process by which new functional neurons are created from neural stem cells existing in the post-natal brain. The entire event is based on a sequence of cellular processes, such as proliferation, specification of cell fate, maturation, and ultimately, synaptic integration into the existing neural circuits. Hence, AN is implicated in structural and functional brain plasticity throughout life. Accumulating evidence shows that impaired AN may underlie some of the abnormal behavioral phenotypes seen in ASD. In this review, we approach the interconnections between the molecular pathways related to AN and ASD. We also discuss existing therapeutic approaches targeting such pathways both in preclinical and clinical studies. A deeper understanding of how ASD and AN reciprocally affect one another could reveal important converging pathways leading to the emergence of psychiatric disorders.
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Affiliation(s)
- Frank Bicker
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Leonardo Nardi
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Jannik Maier
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Verica Vasic
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Michael J Schmeisser
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany.,Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
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3
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Melrose J, Hayes AJ, Bix G. The CNS/PNS Extracellular Matrix Provides Instructive Guidance Cues to Neural Cells and Neuroregulatory Proteins in Neural Development and Repair. Int J Mol Sci 2021; 22:ijms22115583. [PMID: 34070424 PMCID: PMC8197505 DOI: 10.3390/ijms22115583] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/11/2021] [Accepted: 05/17/2021] [Indexed: 02/07/2023] Open
Abstract
Background. The extracellular matrix of the PNS/CNS is unusual in that it is dominated by glycosaminoglycans, especially hyaluronan, whose space filling and hydrating properties make essential contributions to the functional properties of this tissue. Hyaluronan has a relatively simple structure but its space-filling properties ensure micro-compartments are maintained in the brain ultrastructure, ensuring ionic niches and gradients are maintained for optimal cellular function. Hyaluronan has cell-instructive, anti-inflammatory properties and forms macro-molecular aggregates with the lectican CS-proteoglycans, forming dense protective perineuronal net structures that provide neural and synaptic plasticity and support cognitive learning. Aims. To highlight the central nervous system/peripheral nervous system (CNS/PNS) and its diverse extracellular and cell-associated proteoglycans that have cell-instructive properties regulating neural repair processes and functional recovery through interactions with cell adhesive molecules, receptors and neuroregulatory proteins. Despite a general lack of stabilising fibrillar collagenous and elastic structures in the CNS/PNS, a sophisticated dynamic extracellular matrix is nevertheless important in tissue form and function. Conclusions. This review provides examples of the sophistication of the CNS/PNS extracellular matrix, showing how it maintains homeostasis and regulates neural repair and regeneration.
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Affiliation(s)
- James Melrose
- Raymond Purves Bone and Joint Research Laboratory, Kolling Institute, Northern Sydney Local Health District, St. Leonards, NSW 2065, Australia
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW 2052, Australia
- Sydney Medical School, Northern, The University of Sydney, Sydney, NSW 2052, Australia
- Faculty of Medicine and Health, The University of Sydney, Royal North Shore Hospital, St. Leonards, NSW 2065, Australia
- Correspondence:
| | - Anthony J. Hayes
- Bioimaging Research Hub, Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK;
| | - Gregory Bix
- Clinical Neuroscience Research Center, Departments of Neurosurgery and Neurology, Tulane University School of Medicine, New Orleans, LA 70112, USA;
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4
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Decreased phenol sulfotransferase activities associated with hyperserotonemia in autism spectrum disorders. Transl Psychiatry 2021; 11:23. [PMID: 33414449 PMCID: PMC7791095 DOI: 10.1038/s41398-020-01125-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 09/29/2020] [Accepted: 10/27/2020] [Indexed: 11/08/2022] Open
Abstract
Hyperserotonemia is the most replicated biochemical abnormality associated with autism spectrum disorders (ASD). However, previous studies of serotonin synthesis, catabolism, and transport have not elucidated the mechanisms underlying this hyperserotonemia. Here we investigated serotonin sulfation by phenol sulfotransferases (PST) in blood samples from 97 individuals with ASD and their first-degree relatives (138 parents and 56 siblings), compared with 106 controls. We report a deficient activity of both PST isoforms (M and P) in platelets from individuals with ASD (35% and 78% of patients, respectively), confirmed in autoptic tissues (9 pineal gland samples from individuals with ASD-an important source of serotonin). Platelet PST-M deficiency was strongly associated with hyperserotonemia in individuals with ASD. We then explore genetic or pharmacologic modulation of PST activities in mice: variations of PST activities were associated with marked variations of blood serotonin, demonstrating the influence of the sulfation pathway on serotonemia. We also conducted in 1645 individuals an extensive study of SULT1A genes, encoding PST and mapping at highly polymorphic 16p11.2 locus, which did not reveal an association between copy number or single nucleotide variations and PST activity, blood serotonin or the risk of ASD. In contrast, our broader assessment of sulfation metabolism in ASD showed impairments of other sulfation-related markers, including inorganic sulfate, heparan-sulfate, and heparin sulfate-sulfotransferase. Our study proposes for the first time a compelling mechanism for hyperserotonemia, in a context of global impairment of sulfation metabolism in ASD.
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Wang M, He J, Zhou Y, Lv N, Zhao M, Wei H, Li R. Integrated analysis of miRNA and mRNA expression profiles in the brains of BTBR mice. Int J Dev Neurosci 2020; 80:221-233. [PMID: 32086829 DOI: 10.1002/jdn.10019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 01/30/2020] [Accepted: 02/18/2020] [Indexed: 01/02/2023] Open
Abstract
The BTBR T+ Itpr3tf (BTBR) mouse has developmental disorders in brain and many aberrant neuroanatomical structures and brain dysfunction. However, identification of the pathological mechanisms underlying abnormal brain development in the brains of BTBR mice is still lacking. Increasingly evidence showed that epigenetics plays an important role in the processes of brain development. In this study, we analyzed microRNA (miRNA) and mRNA expression profiles in the cortical brain tissue from BTBR mice, using RNA sequencing. As compared to C57BL/6J (B6) mice, 1,271 differentially expressed genes (DEGs) and 36 known differentially expressed miRNAs (DEMs) were found in the brain from BTBR mice. The functional annotation and categories of DEGs and DEMs were analyzed. Integration analysis identified 103 known miRNA-mRNA interaction pairs. We further verified selected several genes and miRNAs which may be associated with brain development using quantitative RT-PCR (qRT-PCR). Finally, we speculate that reduced myelin-associated oligodendrocytic basic protein and transmembrane proteins 260 may be linked with abnormal brain development in BTBR mice.
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Affiliation(s)
- Min Wang
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, China
| | - Jing He
- Department of Medical Imaging, Shanxi Medical University, Taiyuan, China
| | - Yun Zhou
- Nephrology Division, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, China
| | - Na Lv
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, China
| | - Min Zhao
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, China
| | - Hongen Wei
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, China
| | - Rongshan Li
- Nephrology Division, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, China
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6
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Hope KA, Flatten D, Cavitch P, May B, Sutcliffe JS, O'Donnell J, Reiter LT. The Drosophila Gene Sulfateless Modulates Autism-Like Behaviors. Front Genet 2019; 10:574. [PMID: 31316544 PMCID: PMC6611434 DOI: 10.3389/fgene.2019.00574] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/31/2019] [Indexed: 01/13/2023] Open
Abstract
Major challenges to identifying genes that contribute to autism spectrum disorder (ASD) risk include the availability of large ASD cohorts, the contribution of many genes overall, and small effect sizes attributable to common gene variants. An alternative approach is to use a model organism to detect alleles that impact ASD-relevant behaviors and ask whether homologous human genes infer ASD risk. Here we utilized the Drosophila genetic reference panel (DGRP) as a tool to probe for perturbation in naturally occurring behaviors in Drosophila melanogaster that are analogous to three behavior domains: impaired social communication, social reciprocity and repetitive behaviors or restricted interests. Using 40 of the available DGRP lines, we identified single nucleotide polymorphisms (SNPs) in or near genes controlling these behavior domains, including ASD gene orthologs (neurexin 4 and neuroligin 2), an intellectual disability (ID) gene homolog (kirre), and a gene encoding a heparan sulfate (HS) modifying enzyme called sulfateless (sfl). SNPs in sfl were associated with all three ASD-like behaviors. Using RNAi knock-down of neuronal sfl expression, we observed significant changes in expressive and receptive communication during mating, decreased grooming behavior, and increased social spacing. These results suggest a role for HS proteoglycan synthesis and/or modification in normal social communication, repetitive behavior, and social interaction in flies. Finally, using the DGRP to directly identify genetic effects relevant to a neuropsychiatric disorder further demonstrates the utility of the Drosophila system in the discovery of genes relevant to human disease.
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Affiliation(s)
- Kevin A Hope
- Integrated Program in Biological Sciences, The University of Tennessee Health Science Center, Memphis, TN, United States.,Department of Neurology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Daniel Flatten
- Christian Brothers University, Memphis, TN, United States
| | - Peter Cavitch
- Integrated Program in Biological Sciences, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Ben May
- Rhodes College, Memphis, TN, United States
| | - James S Sutcliffe
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, United States.,Department of Psychiatry, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Janis O'Donnell
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, United States
| | - Lawrence T Reiter
- Department of Neurology, The University of Tennessee Health Science Center, Memphis, TN, United States.,Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States.,Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, TN, United States
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7
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Zhang Z, Dawson PA, Piper M, Simmons DG. Postnatal N-acetylcysteine administration rescues impaired social behaviors and neurogenesis in Slc13a4 haploinsufficient mice. EBioMedicine 2019; 43:435-446. [PMID: 30956169 PMCID: PMC6557756 DOI: 10.1016/j.ebiom.2019.03.081] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 03/26/2019] [Accepted: 03/27/2019] [Indexed: 12/31/2022] Open
Abstract
Background Sulfate availability is crucial for the sulfonation of brain extracellular matrix constituents, membrane phospholipids, neurosteroids, and neurotransmitters. Observations from humans and mouse models suggest dysregulated sulfate levels may be associated with neurodevelopmental disorders, such as autism. However, the cellular mechanisms governing sulfate homeostasis within the developing or adult brain are not fully understood. Methods We utilized a mouse model with a conditional allele for the sulfate transporter Slc13a4, and a battery of behavioral tests, to assess the effects of disrupted sulfate transport on maternal behaviors, social interactions, memory, olfaction, exploratory behavior, anxiety, stress, and metabolism. Immunohistochemistry examined neurogenesis within the stem cells niches. Findings The sulfate transporter Slc13a4 plays a critical role in postnatal brain development. Slc13a4 haploinsufficiency results in significant behavioral phenotypes in adult mice, notably impairments in social interaction and long-term memory, as well as increased neurogenesis in the subventricular stem cell niche. Conditional gene deletion shows these phenotypes have a developmental origin, and that full biallelic expression of Slc13a4 is required only in postnatal development. Furthermore, administration of N-acetylcysteine (NAC) within postnatal window P14-P30 prevents the onset of phenotypes in adult Slc13a4+/− mice. Interpretation Slc13a4 haploinsufficient mice highlight a requirement for adequate sulfate supply in postnatal development for the maturation of important social interaction and memory pathways. With evidence suggesting dysregulated sulfate biology may be a feature of some neurodevelopmental disorders, the utility of sulfate levels as a biomarker of disease and NAC administration as an early preventative measure should be further explored.
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Affiliation(s)
- Zhe Zhang
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St. Lucia, QLD 4072, Australia; Mater Research Institute, The University of Queensland, Woolloongabba, QLD 4102, Australia
| | - Paul Anthony Dawson
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St. Lucia, QLD 4072, Australia; Mater Research Institute, The University of Queensland, Woolloongabba, QLD 4102, Australia
| | - Michael Piper
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St. Lucia, QLD 4072, Australia; Queensland Brain Institute, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - David Gordon Simmons
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St. Lucia, QLD 4072, Australia; Mater Research Institute, The University of Queensland, Woolloongabba, QLD 4102, Australia.
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8
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Pearson BL, Crawley JN, Eilam D, Pentkowski NS, Summers CH. Curiosity as an approach to ethoexperimental analysis: Behavioral neuroscience as seen by students and colleagues of Bob Blanchard. Neurosci Biobehav Rev 2017; 76:415-422. [PMID: 27018381 PMCID: PMC5035557 DOI: 10.1016/j.neubiorev.2016.03.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/16/2016] [Accepted: 03/21/2016] [Indexed: 01/05/2023]
Abstract
This review is a synopsis of an International Behavioral Neuroscience Society (IBNS) symposium which focused on the elements of Behavioral Neuroscience for which Robert J. Blanchard was a Pioneer, Leading Expert, Advocate, Mentor, and Sage. Bob Blanchard's work demonstrably changed our broad understanding of animal behavior, and led the way to experimental design and analysis for studies of animal behavior that helped to clarify the deep complexity and subtleties of behavior. Bob's impact on the field of Behavioral Neuroscience includes the behavior, neurocircuitry, neurochemistry, and pharmacology related to social interactions, aggressive behavior, defensive behaviors, flight, freezing, threat, attack, risk assessment, anxiety disorders, animal models, models of social behavior, and autism. The methods and designs developed by Bob Blanchard over a lifetime have been adopted by scientists around the world, and form a standard of excellence in the field. The article addresses these topics in a way that presents developments in the field, describes the newest research data, and pays tribute to a great scientist and founder of this field of work, Bob Blanchard.
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Affiliation(s)
- Brandon L Pearson
- German Center for Neurodegenerative Diseases, Ludwig-Erhard Allee 2, Bonn 53179, Germany.
| | - Jacqueline N Crawley
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Room 1001A Research II Building 96, 4625 2nd Avenue, Sacramento, CA 95817, USA
| | - David Eilam
- Department of Zoology, Tel-Aviv University, Israel
| | - Nathan S Pentkowski
- Department of Psychology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Cliff H Summers
- Department of Biology, University of South Dakota, Vermillion, SD 57069, USA; Neuroscience Group, BBS, Sanford School of Medicine, University of South Dakota, Vermillion, SD 57069, USA.
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9
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Meyza KZ, Blanchard DC. The BTBR mouse model of idiopathic autism - Current view on mechanisms. Neurosci Biobehav Rev 2017; 76:99-110. [PMID: 28167097 DOI: 10.1016/j.neubiorev.2016.12.037] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 12/17/2016] [Accepted: 12/19/2016] [Indexed: 02/07/2023]
Abstract
Autism spectrum disorder (ASD) is the most commonly diagnosed neurodevelopmental disorder, with current estimates of more than 1% of affected children across nations. The patients form a highly heterogeneous group with only the behavioral phenotype in common. The genetic heterogeneity is reflected in a plethora of animal models representing multiple mutations found in families of affected children. Despite many years of scientific effort, for the majority of cases the genetic cause remains elusive. It is therefore crucial to include well-validated models of idiopathic autism in studies searching for potential therapeutic agents. One of these models is the BTBR T+Itpr3tf/J mouse. The current review summarizes data gathered in recent research on potential molecular mechanisms responsible for the autism-like behavioral phenotype of this strain.
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Affiliation(s)
- K Z Meyza
- Laboratory of Emotions' Neurobiology, Nencki Institute of Experimental Biology, 3 Pasteur Street, Warsaw, 02-093, Poland.
| | - D C Blanchard
- Department of Psychology, University of Hawaii at Manoa,1993 East-West Road, Honolulu, HI 96822, USA
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10
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Dwyer CA, Esko JD. Glycan susceptibility factors in autism spectrum disorders. Mol Aspects Med 2016; 51:104-14. [PMID: 27418189 DOI: 10.1016/j.mam.2016.07.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 07/06/2016] [Indexed: 11/16/2022]
Abstract
Idiopathic autism spectrum disorders (ASDs) are neurodevelopmental disorders with unknown etiology. An estimated 1:68 children in the U.S. are diagnosed with ASDs, making these disorders a substantial public health issue. Recent advances in genome sequencing have identified numerous genetic variants across the ASD patient population. Many genetic variants identified occur in genes that encode glycosylated extracellular proteins (proteoglycans or glycoproteins) or enzymes involved in glycosylation (glycosyltransferases and sulfotransferases). It remains unknown whether "glycogene" variants cause changes in glycosylation and whether they contribute to the etiology and pathogenesis of ASDs. Insights into glycan susceptibility factors are provided by studies in the normal brain and congenital disorders of glycosylation, which are often accompanied by ASD-like behaviors. The purpose of this review is to present evidence that supports a contribution of extracellular glycans and glycoconjugates to the etiology and pathogenesis of idiopathic ASDs and other types of pervasive neurodevelopmental disorders.
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Affiliation(s)
- Chrissa A Dwyer
- Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jeffrey D Esko
- Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093, USA.
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11
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Li Q, Chan SY, Wong KK, Wei R, Leung YO, Ding AY, Hui TCK, Cheung C, Chua SE, Sham PC, Wu EX, McAlonan GM. Tspyl2 Loss-of-Function Causes Neurodevelopmental Brain and Behavior Abnormalities in Mice. Behav Genet 2016; 46:529-37. [PMID: 26826030 PMCID: PMC4886156 DOI: 10.1007/s10519-015-9777-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 12/09/2015] [Indexed: 01/04/2023]
Abstract
Testis specific protein, Y-encoded-like 2 (TSPYL2) regulates the expression of genes encoding glutamate receptors. Glutamate pathology is implicated in neurodevelopmental conditions such as autism spectrum disorder, attention deficit hyperactivity disorder (ADHD) and schizophrenia. In line with this, a microduplication incorporating the TSPYL2 locus has been reported in people with ADHD. However, the role of Tspyl2 remains unclear. Therefore here we used a Tspyl2 loss-of-function mouse model to directly examine how this gene impacts upon behavior and brain anatomy. We hypothesized that Tspyl2 knockout (KO) would precipitate a phenotype relevant to neurodevelopmental conditions. In line with this prediction, we found that Tspyl2 KO mice were marginally more active, had significantly impaired prepulse inhibition, and were significantly more 'sensitive' to the dopamine agonist amphetamine. In addition, the lateral ventricles were significantly smaller in KO mice. These findings suggest that disrupting Tspyl2 gene expression leads to behavioral and brain morphological alterations that mirror a number of neurodevelopmental psychiatric traits.
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Affiliation(s)
- Qi Li
- Department of Psychiatry, The University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory for Cognitive and Brain Sciences, The University of Hong Kong, Hong Kong SAR, China
- HKU-SIRI, The University of Hong Kong, Hong Kong SAR, China
| | - Siu Yuen Chan
- Department of Paediatrics and Adolescent Medicine, The University of Hong Kong, Hong Kong SAR, China.
| | - Kwun K Wong
- Department of Paediatrics and Adolescent Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Ran Wei
- Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan, China
| | - Yu On Leung
- Department of Psychiatry, The University of Hong Kong, Hong Kong SAR, China
| | - Abby Y Ding
- Medical Physics and Research Department, Hong Kong Sanatorium and Hospital, The University of Hong Kong, Hong Kong SAR, China
| | - Tomy C K Hui
- Department of Psychiatry, The University of Hong Kong, Hong Kong SAR, China
| | - Charlton Cheung
- Department of Psychiatry, The University of Hong Kong, Hong Kong SAR, China
| | - Siew E Chua
- Department of Psychiatry, The University of Hong Kong, Hong Kong SAR, China
| | - Pak C Sham
- Department of Psychiatry, The University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory for Cognitive and Brain Sciences, The University of Hong Kong, Hong Kong SAR, China
- Genome Research Centre, The University of Hong Kong, Hong Kong SAR, China
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Grainne M McAlonan
- Department of Forensic and Neurodevelopmental Science, Institute of Psychiatry, Psychology and Neuroscience, King's College, London, UK.
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12
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Yang M, Lewis F, Foley G, Crawley JN. In tribute to Bob Blanchard: Divergent behavioral phenotypes of 16p11.2 deletion mice reared in same-genotype versus mixed-genotype cages. Physiol Behav 2016; 146:16-27. [PMID: 26066718 DOI: 10.1016/j.physbeh.2015.04.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 04/08/2015] [Accepted: 04/11/2015] [Indexed: 01/19/2023]
Abstract
Mouse models offer indispensable heuristic tools for studying genetic and environmental causes of neuropsychiatric disorders, including autism. Development of useful animal models of complex human behaviors depends not only on extensive knowledge of the human disease, but also on a deep understanding of animal behavior and ethology. Robert and Caroline Blanchard pioneered a number of elegant social paradigms in rodents. Their early work led to systematic delineations of rodent naturalist defensive behaviors,which were proven to be highly useful models of human psychiatric disorders, including fear and anxiety. Their work using the Visible Burrow System to study social stress in rats represented an unprecedented approach to study biological mechanisms of depression. In recent years, their extensive knowledge of mouse behavior and ethology enabled them to quickly become leading figures in the field of behavioral genetics of autism. To commemorate Robert Blanchard's influences on animal models of human psychiatric disorders, here we describe a study conceptualized and led by Mu Yang who was trained as a graduate student in the Blanchard laboratory in the early 2000s. This investigation focuses on social housing in a genetic mouse model of 16p11.2 deletion syndrome. Heterozygous deletions and duplications of a segment containing about 29 genes on human chromosome 16 appear in approximately 0.5–1% of all cases of autism. 16p11.2 deletion syndrome is also associated with intellectual disabilities and speech impairments. Our previous studies showed that a mouse model of 16p11.2 deletion syndrome exhibited deficits in vocalizations and novel object recognition, as compared to wildtype littermate control cagemates. In the spirit of Bob Blanchard's careful attention to the role of social dominance in rodent behaviors, we became interested in the question of whether behavioral outcomes of a mutation differ when mutants are housed in mixed genotype cages, versus housing only mutants together in one group cage, and only wildtype littermates together in another group cage after weaning. 16p11.2 deletion presented a particularly good model organism to investigate this question, because the heterozygotes are smaller than their wildtype littermates, and may therefore become subordinate to their larger cagemates.Wildtype and heterozygotes were housed with cagemates of the same genotype (same-genotype cage) or with cagemates of the opposite genotype (mixed-genotype cage). Current results replicated social vocalization and object recognition deficits that we previously found in heterozygotes living in mixed-genotype cages. In contrast, heterozygotes that lived in same-genotype cages emitted normal numbers of vocalizations during male–female interactions, and displayed normal novel object recognition, indicating that the deletion per se was not sufficient to cause cognitive or social deficits. Social approach, same-sex social interaction, anxiety-related behavior, depression-related behavior, and open field exploration were not different between genotypes, and were not affected by housing in mixed versus in same-genotype cages. These findings suggest that elements of the home cage social environment could interact with genotype to impact aspects of disease phenotypes. Current findings are discussed as potentially reflecting behavioral deficits resulted from social stress, as inspired by a seminal paper by Bob and Caroline Blanchard [1].
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13
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Pérez C, Sawmiller D, Tan J. The role of heparan sulfate deficiency in autistic phenotype: potential involvement of Slit/Robo/srGAPs-mediated dendritic spine formation. Neural Dev 2016; 11:11. [PMID: 27089953 PMCID: PMC4836088 DOI: 10.1186/s13064-016-0066-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 04/12/2016] [Indexed: 01/24/2023] Open
Abstract
Autism Spectrum Disorders (ASD) are the second most common developmental cause of disability in the United States. ASDs are accompanied with substantial economic and emotional cost. The brains of ASD patients have marked structural abnormalities, in the form of increased dendritic spines and decreased long distance connections. These structural differences may be due to deficiencies in Heparin Sulfate (HS), a proteoglycan involved in a variety of neurodevelopmental processes. Of particular interest is its role in the Slit/Robo pathway. The Slit/Robo pathway is known to be involved in the regulation of axonal guidance and dendritic spine formation. HS mediates the Slit/Robo interaction; without its presence Slit's repulsive activity is abrogated. Slit/Robo regulates dendritic spine formation through its interaction with srGAPs (slit-robo GTPase Activating Proteins), which leads to downstream signaling, actin cytoskeleton depolymerization and dendritic spine collapse. Through interference with this pathway, HS deficiency can lead to excess spine formation.
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Affiliation(s)
- Christine Pérez
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry and Behavioral Neurosciences, Morsani College of Medicine, University of South Florida, 3515 E Fletcher Ave., Tampa, FL 33613 USA
| | - Darrell Sawmiller
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry and Behavioral Neurosciences, Morsani College of Medicine, University of South Florida, 3515 E Fletcher Ave., Tampa, FL 33613 USA
| | - Jun Tan
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry and Behavioral Neurosciences, Morsani College of Medicine, University of South Florida, 3515 E Fletcher Ave., Tampa, FL 33613 USA
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14
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In Sickness and in Health: Perineuronal Nets and Synaptic Plasticity in Psychiatric Disorders. Neural Plast 2015; 2016:9847696. [PMID: 26839720 PMCID: PMC4709762 DOI: 10.1155/2016/9847696] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/27/2015] [Indexed: 12/25/2022] Open
Abstract
Rapidly emerging evidence implicates perineuronal nets (PNNs) and extracellular matrix (ECM) molecules that compose or interact with PNNs, in the pathophysiology of several psychiatric disorders. Studies on schizophrenia, autism spectrum disorders, mood disorders, Alzheimer's disease, and epilepsy point to the involvement of ECM molecules such as chondroitin sulfate proteoglycans, Reelin, and matrix metalloproteases, as well as their cell surface receptors. In many of these disorders, PNN abnormalities have also been reported. In the context of the “quadripartite” synapse concept, that is, the functional unit composed of the pre- and postsynaptic terminals, glial processes, and ECM, and of the role that PNNs and ECM molecules play in regulating synaptic functions and plasticity, these findings resonate with one of the most well-replicated aspects of the pathology of psychiatric disorders, that is, synaptic abnormalities. Here we review the evidence for PNN/ECM-related pathology in these disorders, with particular emphasis on schizophrenia, and discuss the hypothesis that such pathology may significantly contribute to synaptic dysfunction.
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15
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Abstract
Proteoglycans (PGs) regulate diverse functions in the central nervous system (CNS) by interacting with a number of growth factors, matrix proteins, and cell surface molecules. Heparan sulfate (HS) and chondroitin sulfate (CS) are two major glycosaminoglycans present in the PGs of the CNS. The functionality of these PGs is to a large extent dictated by the fine sulfation patterns present on their glycosaminoglycan (GAG) chains. In the past 15 years, there has been a significant expansion in our knowledge on the role of HS and CS chains in various neurological processes, such as neuronal growth, regeneration, plasticity, and pathfinding. However, defining the relation between distinct sulfation patterns of the GAGs and their functionality has thus far been difficult. With the emergence of novel tools for the synthesis of defined GAG structures, and techniques for their characterization, we are now in a better position to explore the structure-function relation of GAGs in the context of their sulfation patterns. In this review, we discuss the importance of GAGs on CNS development, injury, and disorders with an emphasis on their sulfation patterns. Finally, we outline several GAG-based therapeutic strategies to exploit GAG chains for ameliorating various CNS disorders.
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Affiliation(s)
- Vimal P Swarup
- Department of Bioengineering, University of Utah, Salt Lake City, 84112 UT , USA
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16
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Rowlands D, Sugahara K, Kwok JCF. Glycosaminoglycans and glycomimetics in the central nervous system. Molecules 2015; 20:3527-48. [PMID: 25706756 PMCID: PMC6272379 DOI: 10.3390/molecules20033527] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 02/09/2015] [Accepted: 02/13/2015] [Indexed: 01/05/2023] Open
Abstract
With recent advances in the construction of synthetic glycans, selective targeting of the extracellular matrix (ECM) as a potential treatment for a wide range of diseases has become increasingly popular. The use of compounds that mimic the structure or bioactive function of carbohydrate structures has been termed glycomimetics. These compounds are mostly synthetic glycans or glycan-binding constructs which manipulate cellular interactions. Glycosaminoglycans (GAGs) are major components of the ECM and exist as a diverse array of differentially sulphated disaccharide units. In the central nervous system (CNS), they are expressed by both neurons and glia and are crucial for brain development and brain homeostasis. The inherent diversity of GAGs make them an essential biological tool for regulating a complex range of cellular processes such as plasticity, cell interactions and inflammation. They are also involved in the pathologies of various neurological disorders, such as glial scar formation and psychiatric illnesses. It is this diversity of functions and potential for selective interventions which makes GAGs a tempting target. In this review, we shall describe the molecular make-up of GAGs and their incorporation into the ECM of the CNS. We shall highlight the different glycomimetic strategies that are currently being used in the nervous system. Finally, we shall discuss some possible targets in neurological disorders that may be addressed using glycomimetics.
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Affiliation(s)
- Dáire Rowlands
- John van Geest Centre for Brain Repair, University of Cambridge, Forvie Site, Robinson Way, Cambridge CB2 0PY, UK.
| | - Kazuyuki Sugahara
- Proteoglycan Signaling and Therapeutics Research Group, Graduate School of Life Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo 001-0021, Japan.
| | - Jessica C F Kwok
- John van Geest Centre for Brain Repair, University of Cambridge, Forvie Site, Robinson Way, Cambridge CB2 0PY, UK.
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17
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Doll CA, Broadie K. Impaired activity-dependent neural circuit assembly and refinement in autism spectrum disorder genetic models. Front Cell Neurosci 2014; 8:30. [PMID: 24570656 PMCID: PMC3916725 DOI: 10.3389/fncel.2014.00030] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 01/21/2014] [Indexed: 01/23/2023] Open
Abstract
Early-use activity during circuit-specific critical periods refines brain circuitry by the coupled processes of eliminating inappropriate synapses and strengthening maintained synapses. We theorize these activity-dependent (A-D) developmental processes are specifically impaired in autism spectrum disorders (ASDs). ASD genetic models in both mouse and Drosophila have pioneered our insights into normal A-D neural circuit assembly and consolidation, and how these developmental mechanisms go awry in specific genetic conditions. The monogenic fragile X syndrome (FXS), a common cause of heritable ASD and intellectual disability, has been particularly well linked to defects in A-D critical period processes. The fragile X mental retardation protein (FMRP) is positively activity-regulated in expression and function, in turn regulates excitability and activity in a negative feedback loop, and appears to be required for the A-D remodeling of synaptic connectivity during early-use critical periods. The Drosophila FXS model has been shown to functionally conserve the roles of human FMRP in synaptogenesis, and has been centrally important in generating our current mechanistic understanding of the FXS disease state. Recent advances in Drosophila optogenetics, transgenic calcium reporters, highly-targeted transgenic drivers for individually-identified neurons, and a vastly improved connectome of the brain are now being combined to provide unparalleled opportunities to both manipulate and monitor A-D processes during critical period brain development in defined neural circuits. The field is now poised to exploit this new Drosophila transgenic toolbox for the systematic dissection of A-D mechanisms in normal versus ASD brain development, particularly utilizing the well-established Drosophila FXS disease model.
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Affiliation(s)
- Caleb A Doll
- Department of Biological Sciences, Vanderbilt University Nashville, TN, USA
| | - Kendal Broadie
- Department of Biological Sciences, Vanderbilt University Nashville, TN, USA ; Kennedy Center for Research on Human Development, Vanderbilt University Nashville, TN, USA
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18
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Pitkänen A, Ndode-Ekane XE, Łukasiuk K, Wilczynski GM, Dityatev A, Walker MC, Chabrol E, Dedeurwaerdere S, Vazquez N, Powell EM. Neural ECM and epilepsy. PROGRESS IN BRAIN RESEARCH 2014; 214:229-62. [DOI: 10.1016/b978-0-444-63486-3.00011-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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19
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Blanchard DC, Summers CH, Blanchard RJ. The role of behavior in translational models for psychopathology: functionality and dysfunctional behaviors. Neurosci Biobehav Rev 2013; 37:1567-77. [PMID: 23791787 PMCID: PMC3800172 DOI: 10.1016/j.neubiorev.2013.06.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 05/31/2013] [Accepted: 06/10/2013] [Indexed: 01/05/2023]
Abstract
The history of science has frequently included a problem-based impetus toward research that can be translated expeditiously into solutions. A current problem is that psychopathologies, typically chronic, contribute hugely to the economic and social burden of medical care, especially in the United States. For behavioral neuroscientists a psychopathology-aimed translational research emphasis particularly involves animal models to facilitate the experimental and invasive work necessary to an understanding of the biology of normal and aberrant behavior. When the etiology of a particular psychopathology is unknown, and there are no specific biomarkers, behavioral parallels between the focal disorder and its putative models become crucial elements in assessing model validity. Evaluation of these parallels is frequently neglected, reflecting in part the lack of a systematic conceptualization of the organization of behavior and how this may be conserved across species. Recent work specifically attempting to bridge this gap suggests that analysis of behaviors that are functional - adaptive in crucial situations such as danger or social contexts - can facilitate an understanding of the parallels between behaviors of human and nonhuman species, including the dysfunctional behaviors of psycho pathologies. As research with animal models comes to provide a more systematic analysis of particular behaviors and their adaptive functions, cross-talk between model and focal psychopathology may be advantageous to understanding both.
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Affiliation(s)
- D Caroline Blanchard
- Pacific Biosciences Research Center, 1993 East West Road, Honolulu, HI 96822, USA.
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Pearson BL, Corley MJ, Vasconcellos A, Blanchard DC, Blanchard RJ. Heparan sulfate deficiency in autistic postmortem brain tissue from the subventricular zone of the lateral ventricles. Behav Brain Res 2013; 243:138-45. [PMID: 23318464 DOI: 10.1016/j.bbr.2012.12.062] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 12/12/2012] [Accepted: 12/14/2012] [Indexed: 01/20/2023]
Abstract
Abnormal cellular growth and organization have been characterized in postmortem tissue from brains of autistic individuals, suggestive of pathology in a critical neurogenic niche, the subventricular zone (SVZ) of the brain lateral ventricles (LV). We examined cellular organization, cell proliferation, and constituents of the extracellular matrix such as N-sulfated heparan sulfate (HS) and laminin (LAM) in postmortem brain tissue from the LV-SVZ of young to elderly individuals with autism (n=4) and age-matched typically developing (TD) individuals (n=4) using immunofluorescence techniques. Strong and systematic reductions in HS immunofluorescence were observed in the LV-SVZ of the TD individuals with increasing age. For young through mature, but not elderly, autistic pair members, HS was reduced compared to their matched TDs. Cellular proliferation (Ki67+) was higher in the autistic individual of the youngest age-matched pair. These preliminary data suggesting that HS may be reduced in young to mature autistic individuals are in agreement with previous findings from the BTBR T+tf/J mouse, an animal model of autism; from mice with genetic modifications reducing HS; and with genetic variants in HS-related genes in autism. They suggest that aberrant extracellular matrix glycosaminoglycan function localized to the subventricular zone of the lateral ventricles may be a biomarker for autism, and potentially involved in the etiology of the disorder.
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Affiliation(s)
- Brandon L Pearson
- Department of Psychology, University of Hawaii, 2530 Dole Street, Honolulu, HI 96822, USA
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21
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Meyza KZ, Defensor EB, Jensen AL, Corley MJ, Pearson BL, Pobbe RLH, Bolivar VJ, Blanchard DC, Blanchard RJ. The BTBR T+ tf/J mouse model for autism spectrum disorders-in search of biomarkers. Behav Brain Res 2012; 251:25-34. [PMID: 22958973 DOI: 10.1016/j.bbr.2012.07.021] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 07/11/2012] [Accepted: 07/12/2012] [Indexed: 12/28/2022]
Abstract
Autism spectrum disorders (ASD) form a common group of neurodevelopmental disorders appearing to be under polygenic control, but also strongly influenced by multiple environmental factors. The brain mechanisms responsible for ASD are not understood and animal models paralleling related emotional and cognitive impairments may prove helpful in unraveling them. BTBR T+ tf/J (BTBR) mice display behaviors consistent with the three diagnostic categories for ASD. They show impaired social interaction and communication as well as increased repetitive behaviors. This review covers much of the data available to date on BTBR behavior, neuroanatomy and physiology in search for candidate biomarkers, which could both serve as diagnostic tools and help to design effective treatments for the behavioral symptoms of ASD.
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Affiliation(s)
- Ksenia Z Meyza
- Pacific Biosciences Research Center, University of Hawaii, 1993 East-west Road, Honolulu, HI 96822, USA
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Corley MJ, Meyza KZ, Blanchard DC, Blanchard RJ. Reduced sulfate plasma concentrations in the BTBR T+tf/J mouse model of autism. Physiol Behav 2012; 107:663-5. [PMID: 22538115 DOI: 10.1016/j.physbeh.2012.04.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 04/10/2012] [Accepted: 04/10/2012] [Indexed: 12/13/2022]
Abstract
Clinical studies have shown that children diagnosed with autism show abnormal sulfate chemistry, which is critical for cellular and metabolic processes. To determine if the inbred BTBR T+tf/J mouse shows autism-relevant aberrations in sulfate chemistry, the present study examined plasma sulfate concentrations in BTBR T+tf/J, inbred C57BL/6J, and outbred CD-1 mice. Results showed that the BTBR T+tf/J mouse exhibits significantly lower plasma sulfate concentrations in comparison to both C57BL/6J and CD-1 mice. These results suggest that the BTBR mouse shows autism-relevant abnormalities in sulfate chemistry and may serve additional utility in examining the role of sulfate and sulfate-dependent systems in relation to autism-relevant behavioral aberrations.
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Affiliation(s)
- Michael J Corley
- Department of Psychology, University of Hawaii, Honolulu, HI, USA.
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23
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Autism-like socio-communicative deficits and stereotypies in mice lacking heparan sulfate. Proc Natl Acad Sci U S A 2012; 109:5052-6. [PMID: 22411800 DOI: 10.1073/pnas.1117881109] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Heparan sulfate regulates diverse cell-surface signaling events, and its roles in the development of the nervous system recently have been increasingly uncovered by studies using genetic models carrying mutations of genes encoding enzymes for its synthesis. On the other hand, the role of heparan sulfate in the physiological function of the adult brain has been poorly characterized, despite several pieces of evidence suggesting its role in the regulation of synaptic function. To address this issue, we eliminated heparan sulfate from postnatal neurons by conditionally inactivating Ext1, the gene encoding an enzyme essential for heparan sulfate synthesis. Resultant conditional mutant mice show no detectable morphological defects in the cytoarchitecture of the brain. Remarkably, these mutant mice recapitulate almost the full range of autistic symptoms, including impairments in social interaction, expression of stereotyped, repetitive behavior, and impairments in ultrasonic vocalization, as well as some associated features. Mapping of neuronal activation by c-Fos immunohistochemistry demonstrates that neuronal activation in response to social stimulation is attenuated in the amygdala in these mice. Electrophysiology in amygdala pyramidal neurons shows an attenuation of excitatory synaptic transmission, presumably because of the reduction in the level of synaptically localized AMPA-type glutamate receptors. Our results demonstrate that heparan sulfate is critical for normal functioning of glutamatergic synapses and that its deficiency mediates socio-communicative deficits and stereotypies characteristic for autism.
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