Local structural connectivity is associated with social cognition in autism spectrum disorder.

The current theory implying local, short-range overconnectivity in autism spectrum disorder, contrasting with long-range underconnectivity, is based on heterogeneous results, on limited data involving functional connectivity studies, on heterogeneous paediatric populations and non-specific methodologies. In this work, we studied short-distance structural connectivity in a homogeneous population of males with high-functioning autism spectrum disorder and used a novel methodology specifically suited for assessing U-shaped short-distance tracts, including a recently developed tractography-based atlas of the superficial white matter fibres. We acquired diffusion-weighted MRI for 58 males (27 subjects with high-functioning autism spectrum disorder and 31 control subjects) and extracted the mean generalized fractional anisotropy of 63 short-distance tracts. Neuropsychological evaluation included Wechsler Adult Intelligence Scale IV (WAIS-IV), Communication Checklist-Adult, Empathy Quotient, Social Responsiveness Scale and Behaviour Rating Inventory of Executive Function-Adult (BRIEF-A). In contradiction with the models of short-range over-connectivity in autism spectrum disorder, we found that patients with autism spectrum disorder had a significantly decreased anatomical connectivity in a component comprising 13 short tracts compared to controls. Specific short-tract atypicalities in temporal lobe and insula were significantly associated with clinical manifestations of autism spectrum disorder such as social awareness, language structure, pragmatic skills and empathy, emphasizing their importance in social dysfunction. Short-range decreased anatomical connectivity may thus be an important substrate of social deficits in autism spectrum disorder, in contrast with current models.

Increased risk of ADHD in families with ASD.

Attention Deficit and Hyperactive Disorder (ADHD) and Autism Spectrum Disorders (ASD) are frequent comorbid neurodevelopmental conditions and the overlap between both disorders remains to be delineated. A more complete understanding of the shared genetic and environmental factors is needed. Using a family-based method, we evaluated the risk of ADHD in a group of relatives with an ASD proband (ASD-) and a group of relatives with an ASD and ADHD proband (ASD+). We enrolled 1245 individuals in the study: 499 probands, their 746 first-degree relatives and 140 controls. We used a multivariate generalized estimating equation (GEE) model, in which the dependent variable was the ADHD diagnosis in the relatives and the independent variable the ASD+ or ASD- in probands. We adjusted for sociodemographic factors (age, sex, IQ) and for the nature of the familial relationship with the affected proband (parent or sibling). Among the probands, there were 287 ASD- and 212 ASD+ individuals. ADHD was more frequent in relatives (19%) than in the control group (7%) (p = 0.001). The risk of ADHD was higher in the ASD+ relatives group than in the ASD- relatives group (GEE model OR 1.58 [95% CI 1.04-2.38], p = 0.032). This result was found in parents (OR 1.96 [95% CI 1.14-3.36], but not in siblings (OR 1.28 [95% CI 0.84-1.94], p = 0.434). Our study provides a representative estimate of the family distribution of ADHD in relatives of ASD probands but supports the modest effect of shared genetic and environmental factors between both disorders.

Intracellular Pathogen Infections and Immune Response in Autism.

BACKGROUND/AIMS: Perinatal exposure to infections during critical developmental periods is a promising area of study in autism spectrum disorder (ASD). Epidemiological data has highlighted this relationship, pointing out significant correlations between perinatal exposure to pathogens and the occurrence of ASD. The aim of this review is to critically examine the present state of the art on intracellular pathogenic infection during pregnancy and postnatally, pointing out possible correlations with the development of ASD. METHODS: We reviewed and collected studies concerning potential associations between intracellular pathogens like viral, bacterial, and parasite infection and the risk of ASD. RESULTS: We included 14 publications, considering bacterial and/or viral infection that demonstrated the potential to trigger ASD. Nine case-control studies were included and 5 of them reported an association between infections and ASD. One of the 2 cohorts investigated demonstrated that maternal infection increased the risk of ASD in the offspring. Three cross-sectional studies demonstrated that ASD patients presented with chronic infections and active neuroinflammatory processes. Most of the reports suggest inflammatory response as a common factor, and interleukin 6 appears to be a key-player in this process. CONCLUSION: The immune responses generated by organisms that cause perinatal maternal infection, i.e., bacteria, viruses, or parasites, have been associated with the development of autism in offspring. Physiological changes transmitted from the mother during chronic or acute inflammation should be further investigated so that modulatory preventive measures can be developed.

Understanding Patterns of Intimate Partner Abuse in Male-Male, Male-Female, and Female-Female Couples.

Intimate Partner Abuse (IPA), a major social problem, can lead to mental health conditions and is implicated in 30 % of female and 5 % of male homicide deaths. We hypothesized that due to distinct relationship structures and power dynamics which are immersed in varying sociocultural contexts, victims of male-male, female-female and female-male dyads experience different patterns of IPA. Our objectives were: (1) To examine the demographic and clinical characteristics of victims of male victim-male abuser (M-M), female victim-male abuser (F-M), male victim-female abuser (M-F), and female victim-female abuser (F-F) dyads. (2) To compare patterns of IPA reported by the victims in these groups. Out of 397 subjects in the general population that attempted this Internet-based study, 214 English-speaking subjects were older than 18 years, had experienced IPA, and provided complete information for the analysis. Victims of IPA were screened and specific methods of abuse were evaluated. M-Ms were significantly more educated (70 %) than other groups. F-Fs experienced more abuse before age 18 by a parent or relative. F-Fs experienced the most physical abuse while M-Ms the least (p = 0.004). Physical abuse or threats of abuse in front of children was reported more in F-Fs (p < 0.01) and least in M-Ms. IPA patterns differ significantly with F-Fs presenting the most physical profile and M-Ms presenting the least.

Fecal Supernatant from Adult with Autism Spectrum Disorder Alters Digestive Functions, Intestinal Epithelial Barrier, and Enteric Nervous System.

Autism Spectrum Disorders (ASDs) are neurodevelopmental disorders defined by impaired social interactions and communication with repetitive behaviors, activities, or interests. Gastrointestinal (GI) disturbances and gut microbiota dysbiosis are frequently associated with ASD in childhood. However, it is not known whether microbiota dysbiosis in ASD patients also occurs in adulthood. Further, the consequences of altered gut microbiota on digestive functions and the enteric nervous system (ENS) remain unexplored. Therefore, we studied, in mice, the ability offecal supernatant (FS) from adult ASD patients to induce GI dysfunctions and ENS remodeling. First, the analyses of the fecal microbiota composition in adult ASD patients indicated a reduced α-diversity and increased abundance of three bacterial 16S rRNA gene amplicon sequence variants compared to healthy controls (HC). The transfer of FS from ASD patients (FS-ASD) to mice decreased colonic barrier permeability by 29% and 58% compared to FS-HC for paracellular and transcellular permeability, respectively. These effects are associated with the reduced expression of the tight junction proteins JAM-A, ZO-2, cingulin, and proinflammatory cytokines TNFα and IL1ß. In addition, the expression of glial and neuronal molecules was reduced by FS-ASD as compared to FS-HC in particular for those involved in neuronal connectivity (ßIII-tubulin and synapsin decreased by 31% and 67%, respectively). Our data suggest that changes in microbiota composition in ASD may contribute to GI alterations, and in part, via ENS remodeling.

Correction: Dectin-1 Polymorphism: A Genetic Disease Specifier in Autism Spectrum Disorders?

[This corrects the article DOI: 10.1371/journal.pone.0137339.].

Persistence of dysfunctional natural killer cells in adults with high-functioning autism spectrum disorders: stigma/consequence of unresolved early infectious events?

Background: Autism spectrum disorders (ASD) are characterized by abnormal neurodevelopment, genetic, and environmental risk factors, as well as immune dysfunctions. Several lines of evidence suggest alterations in innate immune responses in children with ASD. To address this question in adults with high-functioning ASD (hf-ASD), we sought to investigate the role of natural killer (NK) cells in the persistence of ASD. Methods: NK cells from 35 adults with hf-ASD were compared to that of 35 healthy controls (HC), selected for the absence of any immune dysfunctions, at different time-points, and over a 2-year follow-up period for four patients. The phenotype and polyfunctional capacities of NK cells were explored according to infectious stigma and clinical parameters (IQ, social, and communication scores). Results: As compared to HC, NK cells from patients with hf-ASD showed a high level of cell activation (p < 0.0001), spontaneous degranulation (p < 0.0001), and interferon-gamma production (p = 0.0004), whereas they were exhausted after in vitro stimulations (p = 0.0006). These data yielded a specific HLA-DR+KIR2DL1+NKG2C+ NK-cell signature. Significant overexpression of NKG2C in hf-ASD patients (p = 0.0005), indicative of viral infections, was inversely correlated with the NKp46 receptor level (r = - 0.67; p < 0.0001), regardless of the IgG status of tested pathogens. Multivariate linear regression analysis also revealed that expression of the late-activating HLA-DR marker was both associated with structural language (r = 0.48; p = 0.007) and social awareness (r = 0.60; p = 0.0007) scores in adult patients with hf-ASD, while KIR2DL1 expression correlated with IQ scores (p = 0.0083). Conclusions: This study demonstrates that adults with hf-ASD have specific NK-cell profile. Presence of NKG2C overexpression together with high-level activation of NK cells suggest an association with underlying pathogens, a hypothesis warranting further exploration in future studies.

Decreased Cortical Thickness in the Anterior Cingulate Cortex in Adults with Autism.

Autism spectrum disorder (ASD) is a developmental disorder underdiagnosed in adults. To date, no consistent evidence of alterations in brain structure has been reported in adults with ASD and few studies were conducted at that age. We analyzed structural magnetic resonance imaging data from 167 high functioning adults with ASD and 195 controls. We ran our analyses on a discovery (n = 301) and a replication sample (n = 61). The right caudal anterior cingulate cortical thickness was significantly thinner in adults with ASD compared to controls in both the discovery and the replication sample. Our work underlines the relevance of studying the brain anatomy of an adult ASD population.

Patients with autism spectrum disorders display reproducible functional connectivity alterations.

Despite the high clinical burden, little is known about pathophysiology underlying autism spectrum disorder (ASD). Recent resting-state functional magnetic resonance imaging (rs-fMRI) studies have found atypical synchronization of brain activity in ASD. However, no consensus has been reached on the nature and clinical relevance of these alterations. Here, we addressed these questions in four large ASD cohorts. Using rs-fMRI, we identified functional connectivity alterations associated with ASD. We tested for associations of these imaging phenotypes with clinical and demographic factors such as age, sex, medication status, and clinical symptom severity. Our results showed reproducible patterns of ASD-associated functional hyper- and hypoconnectivity. Hypoconnectivity was primarily restricted to sensory-motor regions, whereas hyperconnectivity hubs were predominately located in prefrontal and parietal cortices. Shifts in cortico-cortical between-network connectivity from outside to within the identified regions were shown to be a key driver of these abnormalities. This reproducible pathophysiological phenotype was partially associated with core ASD symptoms related to communication and daily living skills and was not affected by age, sex, or medication status. Although the large effect sizes in standardized cohorts are encouraging with respect to potential application as a treatment and for patient stratification, the moderate link to clinical symptoms and the large overlap with healthy controls currently limit the usability of identified alterations as diagnostic or efficacy readout.

Neuromodulatory processes of the brain-gut axis.

Brain-gut axis represents a complex reflex circuit that integrates the communication between cortex and the digestive system. Disturbances of the neuromodulatory processes in the brain-gut axis generate functional digestive disorders mainly centered on the pain symptoms and motility disorders. This article reviews structural and patho-physiological aspects of the brain-gut axis and explains how the neuromodulatory interventions currently used in order to treat GI conditions related to the brain-gut axis disturbances. The neuromodulation can be realized by pharmacological targeting mainly receptors in the periphery or using electrical stimulation applied at different levels of the nervous system or directly in the muscular layers of the bowels resulting in modulation of the digestive system activity. The efficacy of the methods using electrostimulation is dependent on the parameters of the physical system used: amplitude, frequency, burst time of the electrical current and also the positioning of the electrodes. While pharmacological interventions are largely used at the moment, neuromodulatory interventions involving electrical stimulation showed clinical efficacy in research trials and have promise.

HLA-class II haplotypes and Autism Spectrum Disorders.

Infections and autoimmunity are associated with autism spectrum disorders (ASD), with both strongly influenced by the genetic regulation of the human leukocyte antigen (HLA) system. The relationship between ASD and the HLA genetic diversity requires further investigation. Using a case control design, the distribution of HLA class II-DRB1 and DQB1 alleles, genotypes and haplotypes were investigated in ASD patients, versus healthy controls (HC). ASD patients meeting DSM-IV TR criteria and HC (474 and 350 respectively) were genotyped at medium resolution using a Luminex-based SSO technology. Comparisons of genotypes, allele frequencies associated with a haplotype analysis were performed. Results indicate: (i) the HLA-DRB1 *11-DQB1*07 haplotype was more prevalent in ASD patients, versus HC (Pc = 0.001), partially replicating previous data and possibly linking to gastro-intestinal (GI)-related pro-inflammatory processes, given that this haplotype associates with pediatric celiac disorders; (ii) the HLA-DRB1 *17-DQB1*02 haplotype was higher in HC, versus ASD patients (Pc = 0.002), indicating that this is a protective haplotype. Using the Autism Diagnostic Interview to assess clinical dimensions, higher scores on social (Pc = 0.006) and non-verbal functioning (Pc = 0.004) associated with the DRB1 *11 DQB1*07 haplotype. Our results support HLA involvement in ASD, with possible relevance to GI and gut-brain axis dysregulation.

Clinical and autoimmune features of a patient with autism spectrum disorder seropositive for anti-NMDA-receptor autoantibody.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by dysfunctions in social interactions resulting from a complex interplay between immunogenetic and environmental risk factors. Autoimmunity has been proposed as a major etiological component of ASD. Whether specific autoantibodies directed against brain targets are involved in ASD remains an open question. Here, we identified within a cohort an ASD patient with multiple circulating autoantibodies, including the well-characterized one against glutamate NMDA receptor (NMDAR-Ab). The patient exhibited alexithymia and previously suffered from two major depressive episodes without psychotic symptoms. Using a single molecule-based imaging approach, we demonstrate that neither NMDAR-Ab type G immunoglobulin purified from the ASD patient serum, nor that from a seropositive healthy subject, disorganize membrane NMDAR complexes at synapses. These findings suggest that the autistic patient NMDAR-Abs do not play a direct role in the etiology of ASD and that other autoantibodies directed against neuronal targets should be investigated.

El trastorno del espectro autista (TEA) es un trastorno del neurodesarrollo caracterizado por dísfunciones en las interacciones sociales que se traducen en un complejo interjuego entre factores de riesgo ambientales e inmunogenéticos. Se ha propuesto a la autoinmunidad como un componente etiológico importante en el TEA. Sigue pendiente saber si hay autoanticuerpos específicos dirigidos contra blancos cerebrales involucrados en el TEA. En este artículo se identificó, dentro de una cohorte, un paciente con TEA con múltiples autoanticuerpos circulantes, incluyendo uno bien caracterizado contra el receptor de glutamato NMDA (NMDAR-Ab). El paciente presentaba alexitimia y previamente había tenido dos episodios depresivos mayores sin síntomas psicóticos. Mediante técnica de imágenes de molécula única se demostró que ni la γ inmunoglobulina purificada del NMDAR-Ab del suero del paciente con TEA, ni la de un sujeto sano seropositivo desorganizaban los complejos de membrana del NMDAR en las sinapsis. Estos hallazgos sugieren que los auto-anticuerpos del NMDAR de pacientes autistas no juegan un papel directo en la etiología del TEA y que se deben investigar otros autoanticuerpos dirigidos contra blancos neuronales.

Les troubles du spectre autistique (TSA) sont des maladies neurodéveloppementales caracterisées par des dysfonctions des interactions sociales provoquées par un jeu complexe entre des facteurs de risque immunogénétiques et environnementaux. L'auto-immunité a été proposée comme composant étiologique majeur des TSA. Il reste à savoir si des auto-anticorps spécifiques dirigés contre des cibles cérébrales sont impliqués dans les TSA. Dans cet article, nous identifions au sein d'une cohorte, un patient TSA ayant de nombreux auto-anticorps circulants dont celui très connu contre le récepteur NMDA du glutamate (NMDAR-Ab). Ce patient présente une alexithymie et a eu antérieurement deux épisodes dépressifs caractérisés sans symptômes psychotiques. Grâce à l'utilisation d'une technique d'imagerie de molécule unique, nous démontrons que ni l'immunoglobuline γ purifiée NMDAR-Ab sérique du patient TSA ni celle d'un patient sain ayant le même anticorps ne désorganisent les complexes membranaires NMDAR au niveau synaptique. Ces résultats semblent indiquer que les auto-anticorps NMDAR-Ab de patients autistes ne jouent pas de rôle direct dans I'étiologie des TSA et que d'autres autoanticorps dirigés contre des cibles neuronales devraient faire l'objet de recherches.

Cerebellar anatomical alterations and attention to eyes in autism.

The cerebellum is implicated in social cognition and is likely to be involved in the pathophysiology of autism spectrum disorder (ASD). The goal of our study was to explore cerebellar morphology in adults with ASD and its relationship to eye contact, as measured by fixation time allocated on the eye region using an eye-tracking device. Two-hundred ninety-four subjects with ASD and controls were included in our study and underwent a structural magnetic resonance imaging scan. Global segmentation and cortical parcellation of the cerebellum were performed. A sub-sample of 59 subjects underwent an eye tracking protocol in order to measure the fixation time allocated to the eye region. We did not observe any difference in global cerebellar volumes between ASD patients and controls; however, regional analyses found a decrease of the volume of the right anterior cerebellum in subjects with ASD compared to controls. There were significant correlations between fixation time on eyes and the volumes of the vermis and Crus I. Our results suggest that cerebellar morphology may be related to eye avoidance and reduced social attention. Eye tracking may be a promising neuro-anatomically based stratifying biomarker of ASD.

Google Trends: Ready for real-time suicide prevention or just a Zeta-Jones effect? An exploratory study.

Two studies have shown that increasing the consultation of the word "suicide" in the Google search engine was associated with a subsequent increase in the prevalence of suicide attempts. The main goal of this article was to explore the trends generated by a key-word search associated with suicide, depression and bipolarity in an attempt to identify general trends (disorders epidemics in the population/"real events" vs newsworthy advertisement/"media event"). Based on previous studies, the frequency of the search words "how to suicide" and "commit suicide" were analyzed for suicide, as well as "depression" (for depressive disorders) and "bipolar disorder". Together, these analyses suggest that the search for the words "how to suicide" or "commit suicide" on the Google search engine may be a good indicator for suicide prevention policies. However, the tool is not developed enough to date to be used as a real time dynamic indicator of suicide epidemics. The frequency of the search for the word "suicide" was associated with those for "depression" but not for "bipolar disorder", but searches for psychiatric conditions seem to be influenced by media events more than by real events in the general population.

Dectin-1 Polymorphism: A Genetic Disease Specifier in Autism Spectrum Disorders?

INTRODUCTION: In autism spectrum disorders (ASD), complex gene-environment interactions contribute to disease onset and progress. Given that gastro-intestinal dysfunctions are common in ASD, we postulated involvement of microbial dysbiosis in ASD and investigated, under a case-control design, the influence of DNA polymorphisms in the CLEC7A gene that encodes a pivotal fungal sensor, Dectin-1. MATERIAL AND METHODS: DNAs from 478 ASD patients and 351 healthy controls (HC) were analyzed for the CLEC7A rs16910631G/A and rs2078178 A/G single nucleotide polymorphisms (SNPs). Differences in the distribution of allele, genotype and haplotype by Chi-square testing and nonparametric analysis by Kruskal-Wallis/Mann-Whitney tests, where appropriate, were performed. The free statistical package R.2.13 software was used for the statistical analysis. RESULTS: We found that the CLEC7A rs2078178 G allele and GG genotype were more prevalent in HC as compared to ASD but failed to reach statistical significance for the latter (pc = 0.01, 0.06 respectively). However, after phenotype-based stratification, the CLEC7A rs2078178 G allele and GG genotype were found to be significantly more frequent in the Asperger group as compared to other ASD subsets (pc = 0.02, 0.01), a finding reinforced by haplotype analysis (rs2078178/rs16910631 G-G/G-G) (pc = 0.002). Further, intellectual quotient (IQ)-based stratification of ASD patients revealed that IQ values increase linearly along the CLEC7A rs2078178 AA, AG and GG genotypes (p = 0.05) and in a recessive manner (GG vs. AA+AG p = 0.02), further confirmed by haplotype distribution (CLEC7A rs2078178-16910631; A-G/A-G, A-G/G-G and G-G/G-G, p = 0.02, G-G/G-G vs. others, p = 0.01). CONCLUSION: Our data suggest that the genetic diversity of CLEC7A gene influences the ASD phenotype by behaving as a disease specifier and imply that the genetic control of innate immune response could determine the ASD phenotype.

Treatment with anti-toxoplasmic activity (TATA) for toxoplasma positive patients with bipolar disorders or schizophrenia: a cross-sectional study.

OBJECTIVE: The association between Toxoplasma gondii seropositivity and respectively Bipolar Disorder (BD) and Schizophrenia/Schizoaffective disorder (SZ) is one of the most studied link between one pathogen and psychiatric disorders. The aim of the present study was thus to retrospectively determine if the administration of an antipsychotic and/or a mood stabilizer having known in vitro Anti-Toxoplasmic Activity (TATA+) was associated with a better clinical outcome in a population of 152 BD or 114 SZ patients and seropositive for T. gondii infection compared to patients receiving a treatment without anti-toxoplasmic activity (TATA-). METHODS: This multicenter study was conducted in an academic public hospital during a 3-years period between 2009 and 2011. All consecutive inpatients and outpatients with SZ or BD diagnosis with a stable treatment for more than 4 weeks were recruited. socio-demographic and clinical characteristics measured with validated scales as well as a serological status for toxoplasmic infection were included. Treatments were classified according to their in vitro antitoxoplasmic activity. A multivariate model was used to determine the clinical characteristics that were significantly different between patients receiving a treatment with no antitoxoplasmic activity compared to others. RESULTS: BD patients with positive serum antibodies against T. gondii presented more lifetime depressive episodes (p = 0.048) after adjustment for age, sex and sociodemographic characteristics when treated by drug having no anti-toxo activity, compared to patients having received drugs with anti-toxo activity. A significant difference was not found in BD toxonegative patients and in SZ toxopositive or toxonegative patients. CONCLUSIONS: It seems to be of importance to consider prescribing a drug with a clear anti-toxoplasmic activity (TATA+) for BD patients seropositive to T. gondii, in particular valproate that was found as the mood stabilizer with the highest antitoxoplasmic activity. Prospective randomized controlled trials are warranted to confirm this preliminary data.

Therapeutic advances in functional gastrointestinal disease: irritable bowel syndrome.

Reported prevalence rates of irritable bowel syndrome (IBS) are between 8% to 20% in the US general population with an average medical expenditure of US$1.35 billion direct and US$205 million indirect costs. Current pathophysiologic theories are based on abnormalities of both the brain and gut, thus setting a new stage for current and future therapeutic approaches. There are numerous treatment options in IBS acting centrally and peripherally by influencing motility and visceral sensitivity. Clinical evidence is variable; however, newer emerging treatments are being evaluated using better-designed clinical trials. Accurate assessment of IBS drug efficacy is still hampered by heterogeneity of the IBS population. Novel methods such as pharmacogenomics or brain imaging may be helpful in the future to better understand and characterize IBS patient subtypes, and this in turn will lead to more specific and efficient therapeutic options. Patient subpopulation measurement of side effects is also a clinical challenge and further understanding could improve treatment efficacy enhancing the patient compliance.