1. Chin EWM, Lim WM, Ma D, Rosales FJ, Goh ELK. {{Choline Rescues Behavioural Deficits in a Mouse Model of Rett Syndrome by Modulating Neuronal Plasticity}}. {Mol Neurobiol};2018 (Sep 15)
Rett syndrome (RTT) is a postnatal neurodevelopmental disorder that primarily affects girls, with 95% of RTT cases resulting from mutations in the methyl-CpG-binding protein 2 (MECP2) gene. Choline, a dietary micronutrient found in most foods, has been shown to be important for brain development and function. However, the exact effects and mechanisms are still unknown. We found that 13 mg/day (1.7 x required daily intake) of postnatal choline treatment to Mecp2-conditional knockout mice rescued not only deficits in motor coordination, but also their anxiety-like behaviour and reduced social preference. Cortical neurons in the brains of Mecp2-conditional knockout mice supplemented with choline showed enhanced neuronal morphology and increased density of dendritic spines. Modelling RTT in vitro by knocking down the expression of the MeCP2 protein with shRNA, we found that choline supplementation to MeCP2-knockdown neurons increased their soma sizes and the complexity of their dendritic arbors. Rescue of the morphological defects could lead to enhanced neurotransmission, as suggested by an observed trend of increased expression of synaptic proteins and restored miniature excitatory postsynaptic current frequency in choline-supplemented MeCP2-knockdown neurons. Through the use of specific inhibitors targeting each of the known physiological pathways of choline, synthesis of phosphatidylcholine from choline was found to be essential in bringing about the changes seen in the choline-supplemented MeCP2-knockdown neurons. Taken together, these data reveal a role of choline in modulating neuronal plasticity, possibly leading to behavioural changes, and hence, a potential for using choline to treat RTT.
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2. Corchon S, Carrillo-Lopez I, Cauli O. {{Quality of life related to clinical features in patients with Rett syndrome and their parents: a systematic review}}. {Metab Brain Dis};2018 (Sep 16)
Patients with a neurodevelopmental disorder such as Rett syndrome (RS), as well as their families, have complex needs that affect their quality of life (QoL). Therefore, both families and patients with RS must be provided with multidisciplinary health care that can identify the clinical features that most affect their QoL and mental health risks. The main objective of this paper is to provide a comprehensive overview of the QoL subdimensions of families affected by RS, including both the parents and children. We conducted a systematic review, following PRISMA criteria, of the data in the PubMed, PsycINFO, Cuiden, and LILACS databases. The results indicated that when considering the family as a whole, RS equally affects the physical and psychological QoL dimensions; the next most affected was the social dimension. According to parents’ reports, seizures are one of the main factors that decreases their QoL. Thus, from a clinical point of view, controlling seizure activity of children with RS is the main way of improving the QoL of their parents. Interventions in patients affected by RS should be based on the improvement of visual contact and concentration, reducing somnolence, and increasing mobility. The subdimensions of QoL that were most affected in parents of girls with RS were those related to mental health and feelings of well-being.
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3. Ghaderi G, Watson SL. {{« In Medical School, You Get Far More Training on Medical Stuff than Developmental Stuff »: Perspectives on ASD from Ontario Physicians}}. {J Autism Dev Disord};2018 (Sep 15)
This study investigated the knowledge and perceived competence of Ontario physicians regarding the diagnosis and treatment of ASDs. Previous research demonstrates that many physicians would like more education regarding diagnosis and treatment of autism spectrum disorders (ASDs). Twenty-seven Ontario physicians filled out a questionnaire and participated in a semi-structured interview. Findings revealed that despite participants’ high perceived knowledge regarding diagnosis and treatment of ASDs, they feel uncomfortable in providing care for this population. Furthermore, many participants stated diagnosing and treating ASDs is not within their scope of practice. Findings have implications for increasing physicians’ knowledge of diagnosis and treatment of ASDs as well as what is required to enhance healthcare for individuals with ASDs and their families.
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4. Ghilan M, Bettio LEB, Noonan A, Brocardo PS, Gil-Mohapel J, Christie BR. {{Impaired spatial processing in a mouse model of fragile X syndrome}}. {Behav Brain Res};2018 (Sep 17);350:72-79.
Fragile X syndrome (FXS) is the most common form of inherited intellectual impairment. The Fmr1(-/y) mouse model has been previously shown to have deficits in context discrimination tasks but not in the elevated plus-maze. To further characterize this FXS mouse model and determine whether hippocampal-mediated behaviours are affected in these mice, dentate gyrus (DG)-dependent spatial processing and Cornu ammonis 1 (CA1)-dependent temporal order discrimination tasks were evaluated. In agreement with previous findings of long-term potentiation deficits in the DG of this transgenic model of FXS, the results reported here demonstrate that Fmr1(-/y) mice perform poorly in the DG-dependent metric change spatial processing task. However, Fmr1(-/y) mice did not present deficits in the CA1-dependent temporal order discrimination task, and were able to remember the order in which objects were presented to them to the same extent as their wild-type littermate controls. These data suggest that the previously reported subregional-specific differences in hippocampal synaptic plasticity observed in the Fmr1(-/y) mouse model may manifest as selective behavioural deficits in hippocampal-dependent tasks.
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5. Koehler L, Fournel A, Albertowski K, Roessner V, Gerber J, Hummel C, Hummel T, Bensafi M. {{Impaired Odor Perception in Autism Spectrum Disorder Is Associated with Decreased Activity in Olfactory Cortex}}. {Chem Senses};2018 (Sep 14)
Autism Spectrum Disorders (ASDs) are characterized by atypical sensory functioning in the visual, tactile, and auditory systems. Although less explored, olfactory changes have been reported in ASD patients. To explore these changes on a neural level, 18 adults with ASD and 18 healthy neurotypical controls were examined in a 2-phase study. Participants were first tested for odor threshold and odor identification. Then, (i) structural magnetic resonance (MR) images of the olfactory bulb were acquired, and (ii) a functional MR imaging olfaction study was conducted. ASD patients exhibited decreased function for odor thresholds and odor identification; this was accompanied by a relatively decreased activation in the piriform cortex. In conclusion, these findings suggest, that the known alterations in olfaction in ASD are rooted in the primary olfactory cortex.
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6. Melancia F, Trezza V. {{Modelling fragile X syndrome in the laboratory setting: A behavioral perspective}}. {Behav Brain Res};2018 (Sep 17);350:149-163.
Fragile X syndrome is the most common form of inherited mental retardation and the most frequent monogenic cause of syndromic autism spectrum disorders. The syndrome is caused by the loss of the Fragile X Mental Retardation Protein (FMRP), a key RNA-binding protein involved in synaptic plasticity and neuronal morphology. Patients show intellectual disability, social deficits, repetitive behaviors and impairments in social communication. The aim of this review is to outline the importance of behavioral phenotyping of animal models of FXS from a developmental perspective, by showing how the behavioral characteristics of FXS at the clinical level can be translated into effective, developmentally-specific and clinically meaningful behavioral readouts in the laboratory setting. After introducing the behavioral features, diagnostic criteria and off-label pharmacotherapy of FXS, we outline how FXS-relevant behavioral features can be modelled in laboratory animals in the course of development: we review the progress to date, discuss how behavioral phenotyping in animal models of FXS is essential to identify potential treatments, and discuss caveats and future directions in this research field.
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7. Syriopoulou-Delli CK, Polychronopoulou SA, Kolaitis GA, Antoniou AG. {{Views of Teachers on Anxiety Symptoms in Students with Autism Spectrum Disorder}}. {J Autism Dev Disord};2018 (Sep 15)
People with autism spectrum disorder (ASD) exhibit comorbidity with anxiety. The aim of this study was the investigation of the perception of teachers on anxiety in school children with ASD. The Scale Teacher Response (SAS-TR) questionnaire was completed by 291 special education and 118 general education teachers, providing data on students in their classes with ASD and of typical development (TD), respectively. According to the total scores on SAS-TR, 46.8% of the children with ASD presented levels of anxiety within the clinical spectrum compared with 15.3% of the children of TD. Gender and age were not associated with the anxiety scores, but in the children with ASD, higher intelligence quotient (IQ) was weakly, and better verbal skills more strongly correlated with a higher anxiety level. Teachers’ awareness of anxiety symptoms in children with ASD may contribute to their social inclusion.
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8. Wang GF, Ye S, Gao L, Han Y, Guo X, Dong XP, Su YY, Zhang X. {{Two single-nucleotide polymorphisms of the RELN gene and symptom-based and developmental deficits among children and adolescents with autistic spectrum disorders in the Tianjin, China}}. {Behav Brain Res};2018 (Sep 17);350:1-5.
Increasing evidence has revealed that genetic variants in Reelin (RELN) gene, especially single-nucleotide polymorphisms (SNPs), correlate with autistic spectrum disorders (ASD) risk; however, no consensus have been reached. This study aimed to provide additional evidence for the association between two SNPs of RELN (i.e., rs736707, rs2229864) and ASD risk, as well as the relationship between RELN gene and symptom-based and developmental deficits of ASD patients in Chinese Han children and adolescents. 157 ASD subjects and 256 typical development (TD) controls were genotyped by TaqMan(R) genotyping assay. ASD patients were assessed by Childhood Autism Rating Scale (CARS), Autism Behavior Checklist (ABC), and Early Childhood Development Questionnaire (ECDQ). We found that SNP rs2229864 was associated with the genetic predisposition of ASD, whereas a negative association between SNP rs2229864 and symptom-based and developmental features was detected. In contrast, RELN rs736707 correlated with the sensory subscale of the ABC, the relating subscale of the ABC and the total score of ABC, although we did not detect a significant association between SNP rs736707 and ASD risk. Furthermore, a significant rs736707-rs2229864 haplotype was detected. Individuals with a CC haplotype were more likely to have ASD, but individuals with a CT haplotype had more chance be TD controls. Further studies using more samples and including more gene variants in RELN are warranted to confirm our results.
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9. Zucker KJ, VanderLaan DP. {{Corrections to Oien, Cicchetti, and Nordahl-Hansen’s (2018) « Gender Dysphoria, Sexuality and Autism Spectrum Disorder: A Systematic Map Review »}}. {J Autism Dev Disord};2018 (Sep 15)