Pubmed du 18/10/2010

Pubmed du jour

2010-10-18 12:03:50

1. Jones CR, Pickles A, Falcaro M, Marsden AJ, Happe F, Scott SK, Sauter D, Tregay J, Phillips RJ, Baird G, Simonoff E, Charman T. {{A multimodal approach to emotion recognition ability in autism spectrum disorders}}. {J Child Psychol Psychiatry} (Oct 18)

Background: Autism spectrum disorders (ASD) are characterised by social and communication difficulties in day-to-day life, including problems in recognising emotions. However, experimental investigations of emotion recognition ability in ASD have been equivocal, hampered by small sample sizes, narrow IQ range and over-focus on the visual modality. Methods: We tested 99 adolescents (mean age 15;6 years, mean IQ 85) with an ASD and 57 adolescents without an ASD (mean age 15;6 years, mean IQ 88) on a facial emotion recognition task and two vocal emotion recognition tasks (one verbal; one non-verbal). Recognition of happiness, sadness, fear, anger, surprise and disgust were tested. Using structural equation modelling, we conceptualised emotion recognition ability as a multimodal construct, measured by the three tasks. We examined how the mean levels of recognition of the six emotions differed by group (ASD vs. non-ASD) and IQ (>/= 80 vs. < 80). Results: We found no evidence of a fundamental emotion recognition deficit in the ASD group and analysis of error patterns suggested that the ASD group were vulnerable to the same pattern of confusions between emotions as the non-ASD group. However, recognition ability was significantly impaired in the ASD group for surprise. IQ had a strong and significant effect on performance for the recognition of all six emotions, with higher IQ adolescents outperforming lower IQ adolescents. Conclusions: The findings do not suggest a fundamental difficulty with the recognition of basic emotions in adolescents with ASD.

2. Urdinguio RG, Fernandez AF, Lopez-Nieva P, Rossi S, Huertas D, Kulis M, Liu CG, Croce C, Calin GA, Esteller M. {{Disrupted microRNA expression caused by Mecp2 loss in a mouse model of Rett syndrome}}. {Epigenetics} (Oct 18);5(7)

MicroRNAs (miRNAs) are short non-coding RNA molecules that regulate post-transcriptional gene expression. They influence a wide range of physiological functions, including neuronal processes, and are regulated by various mechanisms, such as DNA methylation. This epigenetic mark is recognized by transcriptional regulators such as the methyl CpG binding protein Mecp2. Rett syndrome is a complex neurological disorder that has been associated with mutations in the gene coding for Mecp2. Thus, we examined the possible miRNA misregulation caused by Mecp2 absence in a mouse model of Rett syndrome. Using miRNA expression microarrays, we observed that the brain of Rett syndrome mice undergoes a disruption of the expression profiles of miRNAs. Among the significantly altered miRNAs (26%, 65 of 245), overall downregulation of these transcripts was the most common feature (71%), while the remaining 30% were upregulated. Further validation by quantitative RT-PCR demonstrated that the most commonly disrupted miRNAs were miR-146a, miR-146b, miR-130, miR-122a, miR-342 and miR-409 (downregulated) and miR-29b, miR329, miR-199b, miR-382, miR-296, miR-221 and miR-92 (upregulated). Most importantly, transfection of miR-146a in a neuroblastoma cell line caused the downregulation of IL-1 receptor-associated kinase 1 (Irak1) levels, suggesting that the identified defect of miR-146a in Rett syndrome mice brains might be responsible for the observed upregulation of Irak1 in this model of the human disease. Overall, we provide another level of molecular deregulation occurring in Rett syndrome that might be useful for understanding the disease and for designing targeted therapies.

3. Villagonzalo KA, Dodd S, Dean O, Gray K, Tonge B, Berk M. {{Oxidative pathways as a drug target for the treatment of autism}}. {Expert Opin Ther Targets} (Oct 18)

Importance of the field: Autism is a severe, pervasive developmental disorder, the aetiology of which is poorly understood. Current pharmacological treatment options for autism are often focused on addressing comorbid behavioural problems, rather than core features of the disorder. Investigation of a new treatment approach is needed. Areas covered in this review: Recent research has indicated a possible role of abnormalities in oxidative homeostasis in the pathophysiology of autism, based on reports that a range of oxidative biomarkers are significantly altered in people with autism. This article reviews the current findings on oxidative stress in autism, including genetic links to oxidative pathways, changes in antioxidant levels and other oxidative stress markers. We conducted a search of the literature up to June 2010, using Medline, Pubmed, PsycINFO, CINAHL PLUS and BIOSIS Previews. What the reader will gain: This review provides an overview of the current understanding of the role of oxidative stress in autism. This will assist in highlighting areas of future therapeutic targets and potential underlying pathophysiology of this disorder. Take home message: Abnormalities in oxidative homeostasis may play a role in the pathophysiology of autism. Antioxidant treatment may form a potential therapeutic pathway for this complex disorder.