L'élévation du numéro de copie des gènes 22q11.2 arrête la maturation développementale de la capacité de la mémoire de travail et la neurogenèse de l'hippocampe chez les adultes

Aperçu: G.M.

La capacité de mémoire de travail, une composante essentielle de la fonction exécutive, s'élargit développementalement depuis l'enfance jusqu'à l'âge adulte. Des anomalies dans ce processus de développement sont observées chez les personnes avec un diagnostic de "trouble du spectre de l'autisme (TSA), dans la schizophrénie et les déficiences intellectuelles (DI), impliquant ce processus atypique dans la trajectoire des troubles neuropsychiatriques du développement.  

Cependant, les substrats cellulaires et neuronaux sous-jacents à ce processus ne sont pas compris. La duplication et la triplication de la variation du nombre de copies de 22q11.2 sont associées de façon constante et solide aux déficits cognitifs du TSA et de la DI chez les humains, et la surexpression des petits segments 22q11.2 récapitule les aspects dimensionnels des troubles neuropsychiatriques du développement chez la souris.  

En utilisant une approche d'expression génique sélective par type de région et de cellule, les chercheurs ont démontré que les élévations des nombres de copies de deux gènes (COMT, Tbx1), codés dans les deux petits segments 22q11.2 dans l'hippocampe, empêche la maturation du développement de la capacité de mémoire de travail chez la souris. 

Ces données fournissent une preuve de l'hypothèse nouvelle selon laquelle les élévations des nombres de copies de ces gènes 22q11.2 modifient la trajectoire développementale de la capacité de la mémoire de travail via une neurogénèse adulte sous-optimale dans l'hippocampe.

Mol Psychiatry. 2017 Aug 22. doi: 10.1038/mp.2017.158.

Copy number elevation of 22q11.2 genes arrests the developmental maturation of working memory capacity and adult hippocampal neurogenesis

Boku S¹, Izumi T^1,2, Abe S¹, Takahashi T¹, Nishi A¹, Nomaru H¹, Naka Y¹, Kang G¹, Nagashima M¹, Hishimoto A¹, Enomoto S¹, Duran-Torres G³, Tanigaki K⁴, Zhang J⁵, Ye K⁶, Kato S⁷, Männistö PT³, Kobayashi K⁷, Hiroi N^1,8,9.

Author information

1

Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY, USA.

2

Department of Neuropharmacology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.

3

Division of Pharmacology and Toxicology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.

4

Research Institute, Shiga Medical Center, Moriyama-shi, Shiga, Japan.

5

Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA.

6

Department of Epidemiology &Population Health, Albert Einstein College of Medicine, Bronx, NY, USA.

7

Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Japan.

8

Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA.

9

Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA.

Abstract

Working memory capacity, a critical component of executive function, expands developmentally from childhood through adulthood. Anomalies in this developmental process are seen in individuals with autism spectrum disorder (ASD), schizophrenia and intellectual disabilities (ID), implicating this atypical process in the trajectory of developmental neuropsychiatric disorders. However, the cellular and neuronal substrates underlying this process are not understood. Duplication and triplication of copy number variants of 22q11.2 are consistently and robustly associated with cognitive deficits of ASD and ID in humans, and overexpression of small 22q11.2 segments recapitulates dimensional aspects of developmental neuropsychiatric disorders in mice. We capitalized on these two lines of evidence to delve into the cellular substrates for this atypical development of working memory. Using a region- and cell-type-selective gene expression approach, we demonstrated that copy number elevations of catechol-O-methyl-transferase (COMT) or Tbx1, two genes encoded in the two small 22q11.2 segments, in adult neural stem/progenitor cells in the hippocampus prevents the developmental maturation of working memory capacity in mice. Moreover, copy number elevations of COMT or Tbx1 reduced the proliferation of adult neural stem/progenitor cells in a cell-autonomous manner in vitro and migration of their progenies in the hippocampus granular layer in vivo. Our data provide evidence for the novel hypothesis that copy number elevations of these 22q11.2 genes alter the developmental trajectory of working memory capacity via suboptimal adult neurogenesis in the hippocampus.Molecular Psychiatry advance online publication, 22 August 2017; doi:10.1038/mp.2017.158.

PMID:28827761

DOI:10.1038/mp.2017.158

Une revue systématique de la qualité de vie des adultes sur le "spectre de l'autisme"

Aperçu: G.M.

Le " trouble du spectre de l'autisme" est associé à des conditions coexistantes qui peuvent nuire à la qualité de vie d'un individu. Aucune étude systématique de la qualité de vie des adultes sur le spectre de l'autisme n'a été menée.  

Les objectifs des chercheurs étaient les suivants: 

1. examiner les preuves concernant la qualité de vie des adultes sur le spectre autistique; 
2. évaluer de manière critique la pratique actuelle dans l'évaluation de la qualité de vie des adultes sur le spectre de l'autisme. 

Sur un total de 827 études identifiées; 14 ont été incluses.

Une seule mesure de qualité de vie conçue pour être utilisée avec la population générale du spectre autistique a été identifiée.  

La qualité de vie des adultes sur le spectre de l'autisme est inférieure à celle des adultes au développement typique, lorsqu'elle est mesurée avec des outils conçus pour la population générale.

Il n'existe pas d'outils de mesure de qualité de vie spécifiques au "trouble du spectre de l'autisme" validés pour être utilisés avec des échantillons représentatifs d'adultes sur le spectre de l'autisme.

Il est urgent de développer des mesures robustes de la qualité de vie des adultes autistes.

Autism. 2017 Aug 1:1362361317714988. doi: 10.1177/1362361317714988.

A systematic review of quality of life of adults on the autism spectrum

Ayres M¹, Parr JR¹, Rodgers J¹, Mason D¹, Avery L¹, Flynn D¹.

Author information

1

Newcastle University, UK.

Abstract

Autism spectrum disorder is associated with co-existing conditions that may adversely affect an individual's quality of life. No systematic review of quality of life of adults on the autism spectrum has been conducted. Our objectives were as follows: (1) review the evidence about quality of life for adults on the autism spectrum; (2) critically appraise current practice in assessing quality of life of adults on the autism spectrum. We searched bibliographic databases and other literature to identify studies using a direct measure of quality of life of adults on the autism spectrum. Hand searching of reference lists, citation searching and personal communication with field experts were also undertaken. In total, 827 studies were identified; 14 were included. Only one quality of life measure designed for use with the general autism spectrum population was identified. Quality of life of adults on the autism spectrum is lower than that of typically developing adults, when measured with tools designed for the general population. There are no comprehensive autism spectrum disorder-specific quality of life measurement tools validated for use with representative samples of adults on the autism spectrum. There is a pressing need to develop robust measures of quality of life of autistic adults.

PMID:28805071

DOI:10.1177/1362361317714988

L'inhibition de l'imitation chez les enfants avec un syndrome de Tourette

Aperçu: G.M.

L'échopraxie, c'est-à-dire l'imitation ouverte et automatique des actions d'autres personnes, est fréquente chez les "patients" avec un diagnostic de syndrome de Gilles de la Tourette, de "trouble du spectre de l'autisme" et chez ceux qui ont des lésions frontales. 

Bien que les tâches de temps de réaction systématique aient confirmé une augmentation de l'imitation automatique dans les deux derniers groupes, les patients adultes avec un syndrome de Tourette semblent compenser les tendances d'imitation automatiques par un ralentissement général des temps de réponse.  

Les résultats suggèrent que les enfants atteints du syndrome de Tourette utilisent déjà des stratégies d'inhibition différentes ou supplémentaires par rapport aux enfants en bonne santé.

J Neuropsychol. 2017 Aug 12. doi: 10.1111/jnp.12132.

Imitation inhibition in children with Tourette syndrome

Brandt VC^1,2, Moczydlowski A³, Jonas M⁴, Boelmans K⁵, Bäumer T¹, Brass M⁶, Münchau A¹.

Author information

1

Department of Paediatric and Adult Movement Disorders and Neuropsychiatry, Institute of Neurogenetics, University of Lübeck, Germany.

2

Department of Psychology, University of Southampton, UK.

3

Department of Neurology, University Medical Center Hamburg-Eppendorf, Germany.

4

Department of Human Resources, Health and Social Affairs, University of Applied Sciences, Cologne, Germany.

5

Department of Neurology, Julius-Maximilians-University, Würzburg, Germany.

6

Department of Experimental Psychology, Ghent University, Belgium.

Abstract

OBJECTIVE:

Echopraxia, that is, the open and automatic imitation of other peoples' actions, is common in patients with Gilles de la Tourette syndrome, autism spectrum disorder, and also those with frontal lobe lesions. While systematic reaction time tasks have confirmed increased automatic imitation in the latter two groups, adult patients with Tourette syndrome appear to compensate for automatic imitation tendencies by an overall slowing in response times. However, whether children with Tourette syndrome are already able to inhibit automatic imitation tendencies has not been investigated.

METHOD:

Fifteen children with Tourette syndrome and 15 healthy children (aged 7-12 years) performed an imitation inhibition paradigm. Participants were asked to respond to an auditory cue by lifting their index finger or their little finger. Participants were simultaneously presented with either compatible or incompatible visual stimuli.

RESULTS:

Overall responses in children with Tourette syndrome were slower than in healthy children. Although responses were faster in compatible than in incompatible trials in both groups, this 'interference effect' was smaller in children with Tourette syndrome.

CONCLUSIONS:

Children with Tourette syndrome have a smaller interference effect than healthy children, indicating an enhanced ability to behaviourally control automatic imitation tendencies at the cost of reacting slower. The results suggest that children with Tourette syndrome already employ different or additional inhibition strategies compared to healthy children.

© 2017 The British Psychological Society.

PMID:28801946

DOI:10.1111/jnp.12132

Symptômes précoces d'autisme chez les nourrissons avec une sclérose tubéreuse complexe

Aperçu: G.M.

La sclérose tubéreuse complexe (TSC) est un syndrome génétique autosomique dominant  qui confère un risque significativement augmenté pour le "trouble du spectre de l'autisme" (TSA), avec 50 à 60% des nourrissons ayant des critères de réunion de TSC pour le TSA à l'âge de 3 ans.  

Dans une étude antérieure de la cohorte longitudinale actuelle, l'équipe a constaté que les nourrissons avec TSC qui développent un TSA (TSC / ASD) montrent des capacités cognitives diminuées qui divergent des nourrissons avec TSC et sans TSA (TSC / no ASD). Le travail a été étendu en se demandant si les nourrissons TSC / TSA (n = 13) différaient des TSC / no ASD (n = 10) et des nourrissons à faible risque de développement et sans TSA (LR; n = 21) dans leur communication sociale au cours de la première année de vie.

Les chercheurs ont examiné les premiers signes de "trouble du spectre de l'autisme" (TSA) chez les nourrissons avec une sclérose tubéreuse complexe (environ 50%) répondant aux critères de TSA à l'âge de 3 ans. Les nourrissons avec TSC et TSA ont montré des déficits dans les comportements de communication sociale à l'âge de 9 mois qui se distinguent clairement des comportements chez les nourrissons avec TSC qui ne développent pas de TSA et chez les nourrissons à faible risque. 

 Les résultats confirment l'importance du dépistage et de l'intervention précoce des TSA pour les nourrissons avec TSC.

Autism Res. 2017 Aug 11. doi: 10.1002/aur.1846.

Early autism symptoms in infants with tuberous sclerosis complex

McDonald NM¹, Varcin KJ², Bhatt R¹, Wu JY³, Sahin M⁴, Nelson CA 3rd⁵, Jeste SS¹.

Author information

1

UCLA Semel Institute of Neuroscience and Human Behavior, David Geffen School of Medicine, 760 Westwood Plaza, Los Angeles, CA, 90095.

2

Telethon Kids Institute, University of Western Australia, 100 Roberts Road, Subiaco, WA, 6008, Australia.

3

Division of Pediatric Neurology, UCLA Mattel Children's Hospital, David Geffen School of Medicine, 10833 Le Conte Ave, MDCC Room 22-474, Los Angeles, CA, 90095.

4

Department of Neurology, Boston Children's Hospital, Translational Neuroscience Center, 300 Longwood Avenue, Boston, MA, 02115.

5

Division of Developmental Medicine, Boston Children's Hospital, Harvard Medical School & Harvard Graduate School of Education, Harvard University, 1 Autumn Street, Boston, MA, 02215.

Abstract

Tuberous sclerosis complex (TSC) is a rare, autosomal dominant genetic syndrome that confers significantly increased risk for autism spectrum disorder (ASD), with 50-60% of infants with TSC meeting criteria for ASD by 3 years of age. In a previous study of the current longitudinal cohort, we found that infants with TSC who develop ASD (TSC/ASD) evidence decreased cognitive abilities that diverge from infants with TSC and no ASD (TSC/no ASD). We extended this work by asking whether TSC/ASD infants (n = 13) differed from TSC/no ASD infants (n = 10) and infants with low developmental risk and no ASD (LR; n = 21) in their social communication functioning during the first year of life. We measured early ASD symptoms with the Autism Observation Scale for Infants (AOSI) at 9 and 12 months of age. At both ages, infants in the TSC/ASD group had significantly higher AOSI total scores than infants in the TSC/no ASD and LR groups, which were not fully explained by differences in cognitive abilities. Several items on the AOSI at both ages were predictive of ASD outcome, particularly those representing core social communication deficits (e.g., social referencing). Our findings signal the need for further study of this population within the first year and provide strong justification for early identification and early intervention targeting social communication skills in infants with TSC. Autism Res 2017. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

LAY SUMMARY:

We examined early signs of autism spectrum disorder (ASD) in infants with tuberous sclerosis complex (TSC), approximately 50% of whom will meet criteria for ASD by age 3. Infants with TSC and ASD showed deficits in social communication behaviors by 9 months of age that were clearly distinguishable from behaviors in infants with TSC who do not develop ASD and low risk infants. Results support the importance of early ASD screening and intervention for infants with TSC.

© 2017 International Society for Autism Research, Wiley Periodicals, Inc.

PMID:28801991

DOI:10.1002/aur.1846

Taux, répartition et implications des mutations de la mosaïque poszygotique dans le trouble du spectre de l'autisme

Aperçu: G.M.

Les chercheurs ont systématiquement analysé les mutations postzygotiques (PZM) dans des séquences entières de la plus grande collection de trios (5 947) avec le trouble du spectre de l'autisme (TSA) disponible, y compris 282 trios non publiés, et effectué un re-séquencement en utilisant de multiples technologies indépendantes. Ils ont identifié 7,5% des mutations de novo en tant que PZM, dont 83,3% n'ont pas été décrits dans des études antérieures.

Les PZM constituent une proportion importante de mutations de novo et contribuent de manière importante au risque de TSA. 

Nat Neurosci. 2017 Jul 17. doi: 10.1038/nn.4598.

Rates, distribution and implications of postzygotic mosaic mutations in autism spectrum disorder

Lim ET^1,2,3,4, Uddin M⁵, De Rubeis S^6,7, Chan Y^3,4, Kamumbu AS^1,2,3, Zhang X^1,2,3, D'Gama AM^1,2,3, Kim SN^1,2,3, Hill RS^1,2,3, Goldberg AP^6,7, Poultney C^6,7, Minshew NJ⁸, Kushima I⁹, Aleksic B⁹, Ozaki N⁹, Parellada M¹⁰, Arango C¹⁰, Penzol MJ¹¹, Carracedo A^12,13,14, Kolevzon A^6,7,15,16,17, Hultman CM¹⁸, Weiss LA¹⁹, Fromer M^6,7,20, Chiocchetti AG²¹, Freitag CM²¹; Autism Sequencing Consortium, Church GM^3,4, Scherer SW^22,23,24,25, Buxbaum JD^6,7,15,16, Walsh CA^1,2,3.

Author information

1

Division of Genetics and Genomics, Manton Center for Orphan Disease Research and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts, USA.

2

Departments of Pediatrics and Neurology, Harvard Medical School, Boston, Massachusetts, USA.

3

Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA.

4

Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts, USA.

5

Mohammed Bin Rashid University of Medicine and Health Sciences, College of Medicine, Dubai, United Arab Emirates.

6

Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai,New York, New York, USA.

7

Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, USA.

8

Department of Psychiatry, Center For Excellence in Autism Research, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.

9

Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan.

10

Child and Adolescent Psychiatry Department, Hospital General Universitario Gregorio Marañón, School of Medicine, Universidad Complutense, IiSGM, CIBERSAM, Madrid, Spain.

11

Child and Adolescent Psychiatry Department, Hospital General Universitario Gregorio Marañón, IiSGM, CIBERSAM, Madrid, Spain.

12

Grupo de Medicina Xenomica, Universidade de Santiago de Compostela, Centro Nacional de Genotipado-Plataforma de Recursos Biomoleculares y Bioinformaticos-Instituto de Salud Carlos III (CeGen-PRB2-ISCIII), Santiago de Compostela, Spain.

13

Grupo de Medicina Xenomica, CIBERER, Fundacion Publica Galega de Medicina Xenomica-SERGAS, Santiago de Compostela, Spain.

14

Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah, Saudi Arabia.

15

Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.

16

The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.

17

Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York, USA.

18

Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.

19

Department of Psychiatry and Institute for Human Genetics, University of California, San Francisco, San Francisco, California, USA.

20

Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.

21

Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Autism Research and Intervention Center of Excellence, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany.

22

The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Ontario, Canada.

23

Program in Genetics and Genome Biology (GGB), The Hospital for Sick Children, Toronto, Ontario, Canada.

24

Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.

25

McLaughlin Centre, University of Toronto, Toronto, Ontario, Canada.

Abstract

We systematically analyzed postzygotic mutations (PZMs) in whole-exome sequences from the largest collection of trios (5,947) with autism spectrum disorder (ASD) available, including 282 unpublished trios, and performed resequencing using multiple independent technologies. We identified 7.5% of de novo mutations as PZMs, 83.3% of which were not described in previous studies. Damaging, nonsynonymous PZMs within critical exons of prenatally expressed genes were more common in ASD probands than controls (P < 1 × 10^-6), and genes carrying these PZMs were enriched for expression in the amygdala (P = 5.4 × 10^-3). Two genes (KLF16 and MSANTD2) were significantly enriched for PZMs genome-wide, and other PZMs involved genes (SCN2A, HNRNPU and SMARCA4) whose mutation is known to cause ASD or other neurodevelopmental disorders. PZMs constitute a significant proportion of de novo mutations and contribute importantly to ASD risk.

PMID:28714951

DOI:10.1038/nn.4598

Agression accrue et absence de comportement maternel chez les souris déficientes en DIO3 sont associés à des anomalies dans les systèmes d'oxérocine et de vasopressine

Aperçu: G.M.

Les hormones thyroïdiennes régulent de nombreux aspects du développement et de la fonction du cerveau, et les altérations dans les niveaux d'action de l'hormone thyroïdienne conduisent à des comportements d'anxiété et de dépression anormaux.  

Un facteur critique est la deiodinase de type 3 (DIO3), qui est située dans les neurones et protège le cerveau de l'hormone thyroïdienne en excès.

Les chercheurs ont examiné si une augmentation locale de l'action de l'hormone thyroïdienne cérébrale secondaire à la carence en DIO3 est une conséquence pour les comportements sociaux. 

Bien que nous n'ayons pas observé d'altérations dans la sociabilité, les souris Dio3 - / - des deux sexes ont montré une augmentation significative des comportements liés à l'agression et des déficits légers dans la fonction olfactive. En outre, 85% des Dio3 - / - femelles n'ont manifesté aucun comportement de récupération des pupins et une agression accrue envers les nouveau-nés.

Les comportements sociaux anormaux des souris Dio3 - / - ont été associés à des altérations sexuellement dimorphiqueses dans la physiologie de l'ocytocine (OXT) et de l'arginine vasopressine (AVP), deux neuropeptides ayant des rôles importants dans la détermination des interactions sociales. Ces altérations comprenaient des taux sériques élevés d'OXT et d'AVP, et une expression anormale d'OXT, d'AVP et de leurs récepteurs dans l'hypothalamus néonatal et adulte. 

 

Genes Brain Behav. 2017 Jul 17. doi: 10.1111/gbb.12400.

Increased Aggression and Lack of Maternal Behavior in DIO3-Deficient Mice are Associated with Abnormalities in Oxytocin and Vasopressin Systems

Stohn JP¹, Martinez ME¹, Zafer M², López-Espíndola D¹, Keyes LM², Hernandez A¹.

Author information

1

Maine Medical Center Research Institute, Center for Molecular Medicine, Scarborough, Maine, USA.

2

Department of Medicine, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA.

Abstract

Thyroid hormones regulate many aspects of brain development and function, and alterations in the levels of thyroid hormone action lead to abnormal anxiety- and depression-like behaviors. A complement of factors in the brain function independently of circulating levels of hormone to strictly controlled local thyroid hormone signaling. A critical factor is the type 3 deiodinase (DIO3), which is located in neurons and protects the brain from excessive thyroid hormone. Here we examined whether a local increase in brain thyroid hormone action secondary to DIO3 deficiency is of consequence for social behaviors. Although we did not observe alterations in sociability, Dio3 -/- mice of both sexes exhibited a significant increase in aggression-related behaviors and mild deficits in olfactory function. In addition, 85% of Dio3 -/- dams manifested no pup-retrieval behavior and increased aggression towards the newborns. The abnormal social behaviors of Dio3 -/- mice were associated with sexually dimorphic alterations in the physiology of oxytocin (OXT) and arginine vasopressin (AVP), two neuropeptides with important roles in determining social interactions. These alterations included low adult serum levels of OXT and AVP, and an abnormal expression of Oxt, Avp and their receptors in the neonatal and adult hypothalamus. Our results demonstrate that DIO3 is essential for normal aggression and maternal behaviors, and indicate that abnormal local regulation of thyroid hormone action in the brain may contribute to the social deficits associated with neurodevelopmental disorders.

This article is protected by copyright. All rights reserved.

PMID:28715127

DOI:10.1111/gbb.12400