Dépouillements

Brain region-specific altered expression and association of mitochondria-related genes in autism / Ayyappan ANITHA in Molecular Autism, (November 2012)  

Public ISBD [article]  inMolecular Autism > (November 2012) . - 12 p. Titre : Brain region-specific altered expression and association of mitochondria-related genes in autism Type de document : Texte imprimé et/ou numérique Auteurs : Ayyappan ANITHA, Auteur ; Kazuhiko NAKAMURA, Auteur ; Ismail THANSEEM, Auteur ; Kazuo YAMADA, Auteur ; Yoshimi IWAYAMA, Auteur ; Tomoko TOYOTA, Auteur ; Hideo MATSUZAKI, Auteur ; Taishi MIYACHI, Auteur ; Satoru YAMADA, Auteur ; Masatsugu TSUJII, Auteur ; Kenji J. TSUCHIYA, Auteur ; Kaori MATSUMOTO, Auteur ; Yasuhide IWATA, Auteur ; Katsuaki SUZUKI, Auteur ; Hironobu ICHIKAWA, Auteur ; Toshiro SUGIYAMA, Auteur ; Takeo YOSHIKAWA, Auteur ; Norio MORI, Auteur Année de publication : 2012 Article en page(s) : 12 p. Langues : Anglais (eng) Mots-clés : Autism  Mitochondria  Postmortem brain  NEFL  Uncoupling protein  Metaxin Index. décimale : PER Périodiques Résumé : BACKGROUND:Mitochondrial dysfunction (MtD) has been observed in approximately five percent of children with autism spectrum disorders (ASD). MtD could impair highly energy-dependent processes such as neurodevelopment, thereby contributing to autism. Most of the previous studies of MtD in autism have been restricted to the biomarkers of energy metabolism, while most of the genetic studies have been based on mutations in the mitochondrial DNA (mtDNA). Despite the mtDNA, most of the proteins essential for mitochondrial replication and function are encoded by the genomic DNA; so far, there have been very few studies of those genes. Therefore, we carried out a detailed study involving gene expression and genetic association studies of genes related to diverse mitochondrial functions.METHODS:For gene expression analysis, postmortem brain tissues (anterior cingulate gyrus (ACG), motor cortex (MC) and thalamus (THL)) from autism patients (n=8) and controls (n=10) were obtained from the Autism Tissue Program (Princeton, NJ, USA). Quantitative real-time PCR arrays were used to quantify the expression of 84 genes related to diverse functions of mitochondria, including biogenesis, transport, translocation and apoptosis. We used the delta delta Ct ([increment][increment]Ct) method for quantification of gene expression. DNA samples from 841 Caucasian and 188 Japanese families were used in the association study of genes selected from the gene expression analysis. FBAT was used to examine genetic association with autism.RESULTS:Several genes showed brain region-specific expression alterations in autism patients compared to controls. Metaxin 2 (MTX2), neurofilament, light polypeptide (NEFL) and solute carrier family 25, member 27 (SLC25A27) showed consistently reduced expression in the ACG, MC and THL of autism patients. NEFL (P = 0.038; Z-score 2.066) and SLC25A27 (P = 0.046; Z-score 1.990) showed genetic association with autism in Caucasian and Japanese samples, respectively. The expression of DNAJC19, DNM1L, LRPPRC, SLC25A12, SLC25A14, SLC25A24 and TOMM20 were reduced in at least two of the brain regions of autism patients.CONCLUSIONS:Our study, though preliminary, brings to light some new genes associated with MtD in autism. If MtD is detected in early stages, treatment strategies aimed at reducing its impact may be adopted. En ligne : http://dx.doi.org/10.1186/2040-2392-3-12 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=202 [article] Brain region-specific altered expression and association of mitochondria-related genes in autism [Texte imprimé et/ou numérique] / Ayyappan ANITHA, Auteur ; Kazuhiko NAKAMURA, Auteur ; Ismail THANSEEM, Auteur ; Kazuo YAMADA, Auteur ; Yoshimi IWAYAMA, Auteur ; Tomoko TOYOTA, Auteur ; Hideo MATSUZAKI, Auteur ; Taishi MIYACHI, Auteur ; Satoru YAMADA, Auteur ; Masatsugu TSUJII, Auteur ; Kenji J. TSUCHIYA, Auteur ; Kaori MATSUMOTO, Auteur ; Yasuhide IWATA, Auteur ; Katsuaki SUZUKI, Auteur ; Hironobu ICHIKAWA, Auteur ; Toshiro SUGIYAMA, Auteur ; Takeo YOSHIKAWA, Auteur ; Norio MORI, Auteur . - 2012 . - 12 p. Langues : Anglais (eng) in Molecular Autism > (November 2012) . - 12 p. Mots-clés : Autism  Mitochondria  Postmortem brain  NEFL  Uncoupling protein  Metaxin Index. décimale : PER Périodiques Résumé : BACKGROUND:Mitochondrial dysfunction (MtD) has been observed in approximately five percent of children with autism spectrum disorders (ASD). MtD could impair highly energy-dependent processes such as neurodevelopment, thereby contributing to autism. Most of the previous studies of MtD in autism have been restricted to the biomarkers of energy metabolism, while most of the genetic studies have been based on mutations in the mitochondrial DNA (mtDNA). Despite the mtDNA, most of the proteins essential for mitochondrial replication and function are encoded by the genomic DNA; so far, there have been very few studies of those genes. Therefore, we carried out a detailed study involving gene expression and genetic association studies of genes related to diverse mitochondrial functions.METHODS:For gene expression analysis, postmortem brain tissues (anterior cingulate gyrus (ACG), motor cortex (MC) and thalamus (THL)) from autism patients (n=8) and controls (n=10) were obtained from the Autism Tissue Program (Princeton, NJ, USA). Quantitative real-time PCR arrays were used to quantify the expression of 84 genes related to diverse functions of mitochondria, including biogenesis, transport, translocation and apoptosis. We used the delta delta Ct ([increment][increment]Ct) method for quantification of gene expression. DNA samples from 841 Caucasian and 188 Japanese families were used in the association study of genes selected from the gene expression analysis. FBAT was used to examine genetic association with autism.RESULTS:Several genes showed brain region-specific expression alterations in autism patients compared to controls. Metaxin 2 (MTX2), neurofilament, light polypeptide (NEFL) and solute carrier family 25, member 27 (SLC25A27) showed consistently reduced expression in the ACG, MC and THL of autism patients. NEFL (P = 0.038; Z-score 2.066) and SLC25A27 (P = 0.046; Z-score 1.990) showed genetic association with autism in Caucasian and Japanese samples, respectively. The expression of DNAJC19, DNM1L, LRPPRC, SLC25A12, SLC25A14, SLC25A24 and TOMM20 were reduced in at least two of the brain regions of autism patients.CONCLUSIONS:Our study, though preliminary, brings to light some new genes associated with MtD in autism. If MtD is detected in early stages, treatment strategies aimed at reducing its impact may be adopted. En ligne : http://dx.doi.org/10.1186/2040-2392-3-12 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=202

Comparing biobehavioral profiles across two social stress paradigms in children with and without autism spectrum disorders / Blythe A. CORBETT in Molecular Autism, (November 2012)  

Public ISBD [article]  inMolecular Autism > (November 2012) . - 10 p. Titre : Comparing biobehavioral profiles across two social stress paradigms in children with and without autism spectrum disorders Type de document : Texte imprimé et/ou numérique Auteurs : Blythe A. CORBETT, Auteur ; Clayton W. SCHUPP, Auteur ; Kimberly E. LANNI, Auteur Année de publication : 2012 Article en page(s) : 10 p. Langues : Anglais (eng) Mots-clés : Cortisol  Autism  Stress  Novelty  Peer  Age Distribution Index. décimale : PER Périodiques Résumé : BACKGROUND:Autism spectrum disorders (ASD) are defined by impairment in reciprocal social interaction and flexible adaptation to the environment. This study compared physiological stress in children with and without ASD exposed to two social stress protocols. We hypothesized that the ASD group would show heightened initial and enduring cortisol levels to the social stressors, which would be moderated by age and intelligence.METHODS:Twenty-seven children with ASD and 32 with typical development (TYP) completed a standardized social-evaluative performance task and a validated paradigm of social play with peers. Physiological stress was measured by salivary cortisol at nine time points. Statistical approaches included repeated-measures linear mixed models and correlation analyses.RESULTS:The average cortisol level of both groups during initial exposure to social situations was significantly greater than baseline levels (ASD, P = 0.018; TYP, P = 0.006). Stress responsivity was significantly different between the groups; the TYP group showed a significant reduction in cortisol over time (P = 0.023), whereas the ASD group maintained an elevated cortisol level (P 0.05). The ASD group evidenced greater variability in between-group, within-group and intra-individual analyses. Age was a positive moderator of stress for the ASD group (P = 0.047), whereas IQ was a negative moderator for the TYP group (P = 0.061).CONCLUSIONS:Initial stress to novel social scenarios is idiosyncratic and predictive of subsequent exposure. Amidst significant variability in cortisol, children with ASD show enhanced and sustained social stress that increases with age. Developmental and cognitive factors differentially moderate stress in children with ASD and TYP, respectively. A model of neuroendocrine reactivity is proposed. En ligne : http://dx.doi.org/10.1186/2040-2392-3-13 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=202 [article] Comparing biobehavioral profiles across two social stress paradigms in children with and without autism spectrum disorders [Texte imprimé et/ou numérique] / Blythe A. CORBETT, Auteur ; Clayton W. SCHUPP, Auteur ; Kimberly E. LANNI, Auteur . - 2012 . - 10 p. Langues : Anglais (eng) in Molecular Autism > (November 2012) . - 10 p. Mots-clés : Cortisol  Autism  Stress  Novelty  Peer  Age Distribution Index. décimale : PER Périodiques Résumé : BACKGROUND:Autism spectrum disorders (ASD) are defined by impairment in reciprocal social interaction and flexible adaptation to the environment. This study compared physiological stress in children with and without ASD exposed to two social stress protocols. We hypothesized that the ASD group would show heightened initial and enduring cortisol levels to the social stressors, which would be moderated by age and intelligence.METHODS:Twenty-seven children with ASD and 32 with typical development (TYP) completed a standardized social-evaluative performance task and a validated paradigm of social play with peers. Physiological stress was measured by salivary cortisol at nine time points. Statistical approaches included repeated-measures linear mixed models and correlation analyses.RESULTS:The average cortisol level of both groups during initial exposure to social situations was significantly greater than baseline levels (ASD, P = 0.018; TYP, P = 0.006). Stress responsivity was significantly different between the groups; the TYP group showed a significant reduction in cortisol over time (P = 0.023), whereas the ASD group maintained an elevated cortisol level (P 0.05). The ASD group evidenced greater variability in between-group, within-group and intra-individual analyses. Age was a positive moderator of stress for the ASD group (P = 0.047), whereas IQ was a negative moderator for the TYP group (P = 0.061).CONCLUSIONS:Initial stress to novel social scenarios is idiosyncratic and predictive of subsequent exposure. Amidst significant variability in cortisol, children with ASD show enhanced and sustained social stress that increases with age. Developmental and cognitive factors differentially moderate stress in children with ASD and TYP, respectively. A model of neuroendocrine reactivity is proposed. En ligne : http://dx.doi.org/10.1186/2040-2392-3-13 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=202

Self-referential and social cognition in a case of autism and agenesis of the corpus callosum / Michael V. LOMBARDO in Molecular Autism, (November 2012)  

Public ISBD [article]  inMolecular Autism > (November 2012) . - 15 p. Titre : Self-referential and social cognition in a case of autism and agenesis of the corpus callosum Type de document : Texte imprimé et/ou numérique Auteurs : Michael V. LOMBARDO, Auteur ; Bhismadev CHAKRABARTI, Auteur ; Meng-Chuan LAI, Auteur ; MRC AIMS CONSORTIUM,, Auteur ; Simon BARON-COHEN, Auteur Année de publication : 2012 Article en page(s) : 15 p. Langues : Anglais (eng) Mots-clés : Autism  Agenesis of the corpus callosum  Self  Theory of mind  Mentalizing  Social cognition Index. décimale : PER Périodiques Résumé : BACKGROUND:While models of autism spectrum conditions (ASC) are emerging at the genetic level of analysis, clear models at higher levels of analysis, such as neuroanatomy, are lacking. Here we examine agenesis of the corpus callosum (AgCC) as a model at the level of neuroanatomy that may be relevant for understanding self-referential and social-cognitive difficulties in ASC.METHODS:We examined performance on a wide array of tests in self-referential and social-cognitive domains in a patient with both AgCC and a diagnosis of ASC. Tests included a depth-of-processing memory paradigm with self-referential and social-cognitive manipulations, self-report measures of self-consciousness, alexithymia, and empathy, as well as performance measures of first-person pronoun usage and mentalizing ability. The performance of the AgCC patient was compared to a group of individuals with ASC but without AgCC and with neurotypical controls. These comparison groups come from a prior study where group differences were apparent across many measures. We used bootstrapping to assess whether the AgCC patient exhibited scores that were within or outside the 95% bias-corrected and accelerated bootstrap confidence intervals observed in both comparison groups.RESULTS:Within the depth-of-processing memory paradigm, the AgCC patient showed decreased memory sensitivity that was more extreme than both comparison groups across all conditions. The patient's most pronounced difficulty on this task emerged in the social-cognitive domain related to information-processing about other people. The patient was similar to the ASC group in benefiting less from self-referential processing compared to the control group. Across a variety of other self-referential (i.e. alexithymia, private self-consciousness) and social-cognitive measures (i.e. self-reported imaginative and perspective-taking subscales of empathy, mentalizing), the AgCC patient also showed more extreme scores than those observed for both of the comparison groups. However, the AgCC patient scored within the range observed in the comparison groups on measures of first-person pronoun usage and self-reported affective empathy subscales.CONCLUSIONS:We conclude that AgCC co-occurring with a diagnosis of ASC may be a relevant model at the level of neuroanatomy for understanding mechanisms involved in self-referential and high-level social-cognitive difficulties in ASC. En ligne : http://dx.doi.org/10.1186/2040-2392-3-14 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=202 [article] Self-referential and social cognition in a case of autism and agenesis of the corpus callosum [Texte imprimé et/ou numérique] / Michael V. LOMBARDO, Auteur ; Bhismadev CHAKRABARTI, Auteur ; Meng-Chuan LAI, Auteur ; MRC AIMS CONSORTIUM,, Auteur ; Simon BARON-COHEN, Auteur . - 2012 . - 15 p. Langues : Anglais (eng) in Molecular Autism > (November 2012) . - 15 p. Mots-clés : Autism  Agenesis of the corpus callosum  Self  Theory of mind  Mentalizing  Social cognition Index. décimale : PER Périodiques Résumé : BACKGROUND:While models of autism spectrum conditions (ASC) are emerging at the genetic level of analysis, clear models at higher levels of analysis, such as neuroanatomy, are lacking. Here we examine agenesis of the corpus callosum (AgCC) as a model at the level of neuroanatomy that may be relevant for understanding self-referential and social-cognitive difficulties in ASC.METHODS:We examined performance on a wide array of tests in self-referential and social-cognitive domains in a patient with both AgCC and a diagnosis of ASC. Tests included a depth-of-processing memory paradigm with self-referential and social-cognitive manipulations, self-report measures of self-consciousness, alexithymia, and empathy, as well as performance measures of first-person pronoun usage and mentalizing ability. The performance of the AgCC patient was compared to a group of individuals with ASC but without AgCC and with neurotypical controls. These comparison groups come from a prior study where group differences were apparent across many measures. We used bootstrapping to assess whether the AgCC patient exhibited scores that were within or outside the 95% bias-corrected and accelerated bootstrap confidence intervals observed in both comparison groups.RESULTS:Within the depth-of-processing memory paradigm, the AgCC patient showed decreased memory sensitivity that was more extreme than both comparison groups across all conditions. The patient's most pronounced difficulty on this task emerged in the social-cognitive domain related to information-processing about other people. The patient was similar to the ASC group in benefiting less from self-referential processing compared to the control group. Across a variety of other self-referential (i.e. alexithymia, private self-consciousness) and social-cognitive measures (i.e. self-reported imaginative and perspective-taking subscales of empathy, mentalizing), the AgCC patient also showed more extreme scores than those observed for both of the comparison groups. However, the AgCC patient scored within the range observed in the comparison groups on measures of first-person pronoun usage and self-reported affective empathy subscales.CONCLUSIONS:We conclude that AgCC co-occurring with a diagnosis of ASC may be a relevant model at the level of neuroanatomy for understanding mechanisms involved in self-referential and high-level social-cognitive difficulties in ASC. En ligne : http://dx.doi.org/10.1186/2040-2392-3-14 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=202