Atopic features in early childhood autism

Assessing the biobehavioral effects of ultramicronized-palmitoylethanolamide monotherapy in autistic adults with different severity levels: a report of two cases

Despite promise of its supplementation as both monotherapy and add-on treatment in autism spectrum disorder (ASD), the biobehavioral effects of Palmitoylethanolamide (PEA) in autistic adults have never been explored so far. We discussed the cases of two autistic adults with different degrees of severity (level 1 and level 2) presenting with symptoms of psychic distress, who were treated with ultramicronized-PEA (um-PEA) 600 mg/day monotherapy for a sustained period of 4 months. The level 1 autistic patient showed improved depressive symptoms and social engagement at a 12-week follow-up, in parallel to a tendency toward reduced inflammatory response and enhanced endocannabinoid (eCB) signaling, partially relapsing after um-PEA discontinuation at four months. Opposedly, the level 2 autistic patient exhibited a generally stable psychosocial functioning for the initial 12 weeks, consistent with basically unchanged immune and eCBs levels, abruptly deteriorating and leading to antipsychotic initiation afterwards. No significant side effects were reported in both cases during the observation period. The two cases suggest that um-PEA could be an effective option for the treatment of psychic distress in level 1 autistic adults, warranting further investigation of its age- and level-specificity and of the biological underpinnings of its therapeutic effect in ASD.

Atopic Dermatitis and Autism Spectrum Disorders: Common Role of Environmental and Clinical Co-Factors in the Onset and Severity of Their Clinical Course

Increasing evidence suggests an association between atopic dermatitis, the most chronic inflammatory disease of the skin, and autism spectrum disorders, which are a group of neurodevelopmental diseases. Inflammation and immune dysregulation associated with genetic and environmental factors seem to characterize the pathophysiological mechanisms of both conditions. We conducted a literature review of the PubMed database aimed at identifying the clinical features and alleged risk factors that could be used in clinical practice to predict the onset of ASD and/or AD or worsen their prognosis in the context of comorbidities.

Examining the association between autism spectrum disorder and atopic eczema: meta-analysis of current evidence

OBJECTIVES

This study aims to investigate the association between autism spectrum disorder (ASD) and atopic eczema (AE), shedding light on potential associations and underlying mechanisms.

METHODS

A comprehensive review of literature was conducted to identify relevant studies published up to August 2023. Various electronic databases, including PubMed, Embase, Scopus, Web of Science, and Cochrane, were searched using specific keywords related to ASD and AE.

RESULTS

The meta-analysis covered a total of 30 studies. The first analysis included 23 studies with a combined total of 147430 eczema patients in the ASD group and 8895446 eczema patients in non-ASD group. We calculated the risk ratio of eczema in ASD and non-ASD groups, which revealed a significantly higher risk of eczema in patients with ASD (RR 1.34; 95% CI 1.03, 1.76). The second analysis included seven studies with a combined total of 3570449 ASD patients in the AE group and 3253973 in the non-Eczema group. The risk ratio of ASD in the Eczema and Non-Eczema groups showed an insignificantly increased risk of ASD in patients with eczema (RR 1.67; 95% CI 0.91, 3.06).

CONCLUSION

This study underscores the possible link between ASD and atopic eczema, shedding light on their potential association.

IMPACT

Our study conducted a meta-analysis on the association between autism spectrum disorder (ASD) and atopic eczema (AE), shedding light on potential associations and underlying mechanisms. The review we conducted covered a total of 30 studies. This study underscores the possible link between ASD and atopic eczema, shedding light on their potential association.

Early childhood neurodevelopmental milestones in children with allergic diseases: the Japan Environment and Children's Study (JECS)

This study investigated the potential link between early childhood allergic diseases and neurodevelopmental milestone attainment during the first 3 years of life. Utilizing data from a large-scale prospective birth cohort study in Japan, encompassing 87,986 children, we examined physician-diagnosed and caregiver-reported allergic conditions, including atopic dermatitis (AD), asthma, and food allergy (FA). Neurodevelopmental milestones were assessed using the Ages and Stages Questionnaires at 1, 1.5, 2, 2.5, and 3 years of age. Stabilized inverse probability-weighted generalized estimating equation models were employed to estimate odds ratios (ORs). Our analysis revealed no significant association of AD and asthma with delay in communication, gross motor, fine motor, problem-solving, and personal-social skills during the initial 3 years of life. However, children with FA showed an increased likelihood of experiencing gross motor delay compared with that shown by those without FA (weighted adjusted OR: 1.14). Despite this, no significant association of FA with other developmental domains was observed. Early childhood allergies may not influence neurodevelopmental delays. However, there is a potential association between FA and delays, specifically in gross motor skills, that warrants routine developmental monitoring and additional investigations.

Ectodermal origins of the skin-brain axis: a novel model for the developing brain, inflammation, and neurodevelopmental conditions

Early life development and its divergence is influenced by multiple genetic, neurological, and environmental factors. Atypical neurodevelopment, such as that observed in autism spectrum disorder, likely begins in early gestation during a period of entwined growth between the brain and epithelial barriers of the skin, gastrointestinal tract, and airway. This review coalesces epidemiological and neuroinflammatory evidence linking cutaneous atopic disease with both reduced skin barrier integrity and determinants of neurodivergence. We consider the shared developmental origin of epidermal and neural tissue with related genetic and environmental risk factors to evaluate potential pre- and postnatal modifiers of the skin-brain connection. Initial postnatal skin barrier integrity may provide a useful marker for both cortical integrity and meaningful subgroups of children showing early neurodevelopmental delays. It may also modify known risk factors to neurodevelopment, such as pathogen caused immune system activation. These novel insights of a skin-brain-neurodevelopment connection may advance detection and intervention opportunities.

Early childhood allergy linked with development of attention deficit hyperactivity disorder and autism spectrum disorder

BACKGROUND

Previous studies reported controversial results regarding the association between allergic disorders and attention deficit hyperactivity disorder (ADHD)/autism spectrum disorder (ASD). The aim of this article was to investigate whether allergic disorders are associated with ADHD/ASD in a large cohort of pediatric patients.

METHODS

A retrospective study using the pediatric (0-18 year) database (ICD-9-CM codes) of Clalit Health Services during the years (2000-2018). Diagnosis of all disorders was made by specialist physicians.

RESULTS

A total of 117 022 consecutive non-selective allergic children diagnosed with one or more allergic disorder (asthma, rhinitis, conjunctivitis, skin, food, or drug allergy) and 116 968 non-allergic children were enrolled to our study. The mean follow-up period was 11 ± 6 years. The presence of allergic disorders in early childhood (mean age of allergic diagnosis 4.5 ± 4.3 years) in boys as well as in girls significantly increased the risk to develop ADHD (O.R 2.45, CI 2.39-2.51; p < .0001), ASD (O.R 1.17, CI 1.08-1.27; p < .0001), or both ADHD + ASD (O.R 1.5, CI 1.35-1.79; p < .0001). Children with more than one allergic comorbidity revealed a much higher risk. In a multivariable analysis (adjusted for age at study entry, number of yearly visits, and gender), the risk of allergic children to develop ADHD and ADHD + ASD, but not ASD alone, remained significantly higher.

CONCLUSION

Allergic disorder in early childhood significantly increased the risk to develop ADHD, and to a less extend ASD, in later life.

Phenotypic overlap between atopic dermatitis and autism

BACKGROUND

Autism, a childhood behavioral disorder, belongs to a large suite of diseases, collectively referred to as autism spectrum disorders (ASD). Though multifactorial in etiology, approximately 10% of ASD are associated with atopic dermatitis (AD). Moreover, ASD prevalence increases further as AD severity worsens, though these disorders share no common causative mutations. We assessed here the link between these two disorders in the standard, valproic acid mouse model of ASD. In prior studies, there was no evidence of skin involvement, but we hypothesized that cutaneous involvement could be detected in experiments conducted in BALB/c mice. BALB/c is an albino, laboratory-bred strain of the house mouse and is among the most widely used inbred strains used in animal experimentation.

METHODS

We performed our studies in valproic acid (VPA)-treated BALB/c hairless mice, a standard mouse model of ASD. Mid-trimester pregnant mice received a single intraperitoneal injection of either valproic acid sodium salt dissolved in saline or saline alone on embryonic day 12.5 and were housed individually until postnatal day 21. Only the brain and epidermis appeared to be affected, while other tissues remain unchanged. At various postnatal time points, brain, skin and blood samples were obtained for histology and for quantitation of tissue sphingolipid content and cytokine levels.

RESULTS

AD-like changes in ceramide content occurred by day one postpartum in both VPA-treated mouse skin and brain. The temporal co-emergence of AD and ASD, and the AD phenotype-dependent increase in ASD prevalence correlated with early appearance of cytokine markers (i.e., interleukin [IL]-4, 5, and 13), as well as mast cells in skin and brain. The high levels of interferon (IFN)γ not only in skin, but also in brain likely account for a significant decline in esterified very-long-chain N-acyl fatty acids in brain ceramides, again mimicking known IFNγ-induced changes in AD.

CONCLUSION

Baseline involvement of both AD and ASD could reflect concurrent neuro- and epidermal toxicity, possibly because both epidermis and neural tissues originate from the embryonic neuroectoderm. These studies illuminate the shared susceptibility of the brain and epidermis to a known neurotoxin, suggesting that the atopic diathesis could be extended to include ASD.

Understanding the Link Between Allergy and Neurodevelopmental Disorders: A Current Review of Factors and Mechanisms

Both allergic diseases and neurodevelopmental disorders are non-communicable diseases (NCDs) that not only impact on the quality of life and but also result in substantial economic burden. Immune dysregulation and inflammation are typical hallmarks in both allergic and neurodevelopmental disorders, suggesting converging pathophysiology. Epidemiological studies provided convincing evidence for the link between allergy and neurodevelopmental diseases such as attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Possible factors influencing the development of these disorders include maternal depression and anxiety, gestational diabetes mellitus, maternal allergic status, diet, exposure to environmental pollutants, microbiome dysbiosis, and sleep disturbances that occur early in life. Moreover, apart from inflammation, epigenetics, gene expression, and mitochondrial dysfunction have emerged as possible underlying mechanisms in the pathogenesis of these conditions. The exploration and understanding of these shared factors and possible mechanisms may enable us to elucidate the link in the comorbidity.

The "Connectivome Theory": A New Model to Understand Autism Spectrum Disorders

The classical approach to autism spectrum disorders (ASD) is often limited to considering their neuro-functional aspects. However, recent scientific literature has shown that ASDs also affect many body systems and apparatuses such as the immune system, the sensory-motor system, and the gut-brain axis. The connective tissue, a common thread linking all these structures, may have a pathogenetic role in the multisystem involvement of ASD. Depending on its different anatomical sites, the connective tissue performs functions of connection and support; furthermore, it acts as a barrier between the external and internal environments, regulating the interchange between the two and performing immunological surveillance. The connective tissue shares a close relationship with the central nervous system, the musculoskeletal system and the immune system. Alterations in brain connectivity are common to various developmental disorders, including ASD, and for this reason here we put forward the hypothesis that alterations in the physiological activity of microglia could be implicated in the pathogenesis of ASD. Also, muscle hypotonia is likely to clinically correlate with an altered sensoriality and, in fact, discomfort or early muscle fatigue are often reported in ASDs. Furthermore, patients with ASD often suffer from intestinal dysfunctions, malabsorption and leaky gut syndrome, all phenomena that may be linked to reduced intestinal connectivity. In addition, at the cutaneous and subcutaneous levels, ASDs show a greater predisposition to inflammatory events due to the lack of adequate release of anti-inflammatory mediators. Alveolar-capillary dysfunctions have also been observed in ASD, most frequently interstitial inflammations, immune-mediated forms of allergic asthma, and bronchial hyper-reactivity. Therefore, in autism, altered connectivity can result in phenomena of altered sensitivity to environmental stimuli. The following interpretative model, that we define as the "connectivome theory," considers the alterations in connective elements of common mesodermal origin located in the various organs and apparatuses and entails the evaluation and interpretation of ASDs through also highlighting somatic elements. We believe that this broader approach could be helpful for a more accurate analysis, as it is able to enrich clinical evaluation and define more multidisciplinary and personalized interventions.

Association between childhood asthma and attention deficit hyperactivity or autism spectrum disorders: A systematic review with meta-analysis

BACKGROUND

Children with asthma are at risk of depression and anxiety and growing evidence suggest they may also be at risk of attention deficit hyperreactivity disorder (ADHD) and autism spectrum disorder (ASD). Here, we conducted a systematic review with meta-analysis of studies investigating association between asthma and ADHD or ASD in children.

METHODS

A comprehensive search using PubMed, EMBASE and Cochrane Library databases was completed in March 2019. Observational human studies published in English, clinic-based or population-based with a healthy comparator group, evaluating asthma-ADHD or asthma-ASD overlap in children 18 years or younger using categorical diagnoses (yes/no) were considered for inclusion. Random effects meta-analysis models were used to analyse data. The Newcastle Ottawa Scale was used to evaluate risk of bias.

RESULTS

A total of 25 asthma-ADHD studies were included of which 17 showed significant positive associations and one a negative association: 17/25 studies were population-based, 19/25 were cross-sectional or cohort studies and 7/25 had a low risk of bias. We performed a meta-analysis of 23 of the studies, which showed a significant association between asthma and ADHD: odds ratio (OR) 1.52 (1.42-1.63), P < .001, I2 = 60%. All studies were adjusted for age and sex and a large proportion; that is, 19/23 were further adjusted for relevant confounders. Seventeen asthma-ASD studies were included, whereof 7 showed a positive association and 3 a negative association; 8/17 were population-based with a cross-sectional study design and 4/17 had a low risk of bias. We performed a meta-analysis of 14 of the studies, which did not show a significant association between asthma and ASD: OR 1.12 (0.93-1.34), P = .24, I2 = 89%. All studies were adjusted for age and sex and 10/14 were further adjusted for relevant confounders.

CONCLUSIONS

This systematic review with meta-analyses shows a significant overlap between asthma and ADHD, but not between asthma and ASD in children. Clinicians taking care of children with asthma or ADHD should be aware of such association to aid an early diagnosis and treatment of such comorbidity.

A meta-analysis of pro-inflammatory cytokines in autism spectrum disorders: Effects of age, gender, and latitude

BACKGROUND

Autism spectrum disorders (ASD) occur in 1.5% of the general population worldwide. Studies suggest that ASD might have more costs than diabetes and attention deficit and hyperactivity disorder by 2025. Dysregulation of the cytokine system is well-documented in ASD. We conducted a meta-analysis of studies providing data on circulating concentrations of pro-inflammatory cytokines in people with ASD compared with control subjects without ASD.

METHODS

We identified potentially eligible studies by systematically searching electronic databases from inception to February 2018.

RESULTS

Thirty-eight studies with total of 2487 participants (1393 patients with ASD and 1094 control subjects) were included in the meta-analysis; 13 for interferon (IFN)-γ, 17 for interleukin (IL)-1β, 22 for IL-6, 19 for tumor necrosis factor (TNF)-α, 4 for IL-1α, 6 for IL-2, 4 for IL-7, 8 for IL-8, 14 for IL-12, 3 for IL-15, 12 for IL-17, 3 for IL-18, 3 for IL-2 receptor, 3 for TNF-β, and 3 for IL-23. We found medium increases in levels of plasma IFN-γ (standardized mean difference, SMD = 0.53) and serum IL-1β (SMD = 0.56) and small increases in levels of blood IL-1β (SMD = 0.35), serum IL-6 (SMD = 0.30) and serum TNF-α (SMD = 0.31) for patients with ASD. Meta-regression analyses identified latitude as a negative moderator of the effect size (ES) of difference in mean levels of IFN-γ (R² = 0.26) and TNF-α (R² = 0.74). Also, difference in the mean age between patients and controls had a negative interaction with the ES of difference in mean levels of IL-1β. In contrast, there was a positive effect of the moderator of difference in the proportion of male subjects between patients and controls on the ES of difference in mean levels of IL-1β. We found no significant alterations in peripheral levels of other pro-inflammatory cytokines including IL-1α, IL-2, IL-2R, IL-3, IL-7, IL-8, IL-12, IL-12p40, IL-12p70, IL-15, IL-17, IL-18, IL-23, TBF-β, and TNFRI/II in patients with ASD.

CONCLUSIONS

This meta-analysis provides evidence for higher concentration of pro-inflammatory cytokines IFN-γ, IL-1β, IL-6, and TNF-α in autistic patents compared with control subjects. Also, meta-regression analyses point to the interaction of latitude, age, and gender with peripheral alterations of associated pro-inflammatory cytokines.

MicroRNA Cross-Involvement in Autism Spectrum Disorders and Atopic Dermatitis: A Literature Review

Autism Spectrum Disorder (ASD) is a category of neurodevelopmental disturbances seriously affecting social skills, to which the scientific community has paid great attention in last decades. To date, their pathogenesis is still unknown, but several studies highlighted the relevance of gene-environment interactions in the onset of ASD. In addition, an immune involvement was seen in a wide number of ASD subjects, leading several researchers to hypothesize a possible common pathogenesis between ASD and immune disturbances, including Atopic Dermatitis (AD). In general, among potential contributing factors, microRNAs (miRNAs), small molecules capable of controlling gene expression and targeting mRNA transcripts, might represent one of the major circulating link, possibly unraveling the connections between neurodevelopmental and immune conditions. Under such premises, we conducted a systematic literature review, under the PRISMA guidelines, trying to define the panel of common miRNAs involved in both ASD and AD. The review retrieved articles published between January 1, 2005, and December 13, 2018, in PubMed, ScienceDirect, PsycARTICLES, and Google Scholar. We found a handful of works dealing with miRNAs in ASD and AD, with the most overlapping dysregulated miRNAs being miR-146 and miR-155. Two possible compounds are abnormally regulated in both ASD and AD subjects, possibly cross-contributing to the interactions between the two disorders, setting the basis to investigate more precisely the possible link between ASD and AD from another, not just clinical, perspective.

Family history of immune conditions and autism spectrum and developmental disorders: Findings from the study to explore early development

Numerous studies have reported immune system disturbances in individuals with autism and their family members; however, there is considerable variability in findings with respect to the specific immune conditions involved, their timing, and the family members affected and little understanding of variation by autism subphenotype. Using data from the Study to Explore Early Development (SEED), a multi-site case-control study of children born 2003-2006 in the United States, we examined the role of family history of autoimmune diseases, asthma, and allergies in autism spectrum disorder (ASD) as well as other developmental disorders (DD). We investigated maternal immune conditions during the pregnancy period, as well as lifetime history of these conditions in several family members (mother, father, siblings, and study child). Logistic regression analyses included 663 children with ASD, 984 children with DD, and 915 controls ascertained from the general population (POP). Maternal history of eczema/psoriasis and asthma was associated with a 20%-40% increased odds of both ASD and DD. Risk estimates varied by specific ASD subphenotypes in association with these exposures. In addition, children with ASD were more likely to have a history of psoriasis/eczema or allergies than POP controls. No association was observed for paternal history or family history of these immune conditions for either ASD or DD. These data support a link between maternal and child immune conditions and adverse neurodevelopmental outcomes, and further suggest that associations may differ by ASD phenotype of the child. Autism Research 2019, 12: 123-135. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Using data from a large multi-site study in the US-the Study to Explore Early Development-we found that women with a history of eczema/psoriasis and asthma are more likely to have children with ASD or DD. In addition, children with ASD are more likely to have a history of psoriasis/eczema or allergies than typically developing children. These data support a link between maternal and child immune conditions and adverse neurodevelopmental outcomes.

Association of Pediatric Allergic Rhinitis with the Ratings of Attention-Deficit/Hyperactivity Disorder

Background

Allergic rhinitis (AR) is currently the most prevalent allergic disease in children and adolescents.

Objective

Surveys conducted by population-based studies of East Asia revealed an increased prevalence of behavioral disorders in patients with AR. Thus, in this study, we explored the prevalence of attention-deficit/hyperactivity disorder (ADHD) in pediatric patients with AR.

Methods

A total of 333 children (6–12 years of age) with AR and a total of 322 age-matched controls were included in this study. An otorhinolaryngologist diagnosed all AR cases and evaluated the severity of the disease. Skin-prick test results for 18 major allergens, Paediatric Rhinoconjunctivitis Quality of Life Questionnaire (PRQLQ), Child Behavior Checklist (CBCL), and Swanson, Nolan, and Pelham version IV (SNAP-IV) scores were recorded.

Results

In total, 320 age-matched controls and 323 children with AR completed the study. With respect to the Total Nasal Symptom Score and the PRQLQ, the condition of the experimental group was more serious than that of the controls. The scores on the hyperactivity/impulsivity and inattention subscales, which evaluate ADHD symptoms, and those on the CBCL subscales were significantly higher in patients with AR than in the controls (all p values were <0.01). From the results of the Pearson correlation, we deduced that there were significant positive correlations between the AR-related data and each subscale of the CBCL and SNAP-IV in the AR group. Moreover, two basic characteristics (males and environmental exposure to tobacco smoke) present significant positive and age showed a significant negative correlations affect ADHD symptom in both the AR group and the control group. Also, in the “pure AR” group, hierarchical regression analyses were performed to determine the subtests of the PRQLQ, which are significant predictors of SNAP-IV and CBCL.

Conclusions

Apart from AR per se, the possible comorbidities of impulsivity and inattention are important when managing children with AR. It is essential to evaluate the symptoms of ADHD in children and adolescents with AR.

Longitudinal association between early atopic dermatitis and subsequent attention-deficit or autistic disorder: A population-based case-control study

Atopic dermatitis (AD) is one of the common allergic diseases in children. The presence of allergic diseases was found to have association with the risk of developing attention-deficit hyperactivity disorder (ADHD) or autistic spectrum disorder (ASD) in children, but it is still inconclusive. This study was to investigate the longitudinal relationship between AD developed during toddlerhood and subsequent development of ADHD or ASD in later childhood. Toddlers born between 1998 and 2008 and diagnosed with AD at the age younger than 3 years and older than 1 month were retrieved from Taiwan's National Health Insurance Research Database. Age- and gender-matched toddlers with no lifetime AD were enrolled as the control group. All enrolled toddlers were followed until 2011 to identify the development of ADHD or ASD. Multivariate Cox regression analysis was performed to analyze the hazard ratios (HRs). The risks associated with allergic comorbidities were analyzed. A total of 18,473 toddlers were enrolled into the AD group. The presence of AD significantly increased the risk of developing ADHD (HR = 2.92, 95% confidence interval [CI] = 2.48-3.45) or ASD (HR = 8.90, 95% CI = 4.98-15.92) when aged 3 years or older. Children from the AD group with 3 comorbidities together, namely, allergic rhinitis, allergic conjunctivitis, and asthma, had the greatest risk of developing ADHD and ASD (ADHD: HR = 4.67, 95% CI = 3.81-5.43; ASD: HR = 16.65, 95% CI = 8.63-30.60). In conclusion, toddlers who suffer from AD at the age younger than 3 years are at a higher risk of developing ADHD and ASD during later childhood. Pediatricians taking care of toddlers with AD should have knowledge of this increased risk of developing ADHD and ASD later in life, especially when children have certain comorbidities such as allergic rhinitis, allergic conjunctivitis, and asthma.

Atopic diseases and inflammation of the brain in the pathogenesis of autism spectrum disorders

Autism spectrum disorders (ASDs) affect as many as 1 in 45 children and are characterized by deficits in sociability and communication, as well as stereotypic movements. Many children also show severe anxiety. The lack of distinct pathogenesis and reliable biomarkers hampers the development of effective treatments. As a result, most children with ASD are prescribed psychopharmacologic agents that do not address the core symptoms of ASD. Autoantibodies against brain epitopes in mothers of children with ASD and many such children strongly correlate with allergic symptoms and indicate an aberrant immune response, as well as disruption of the blood-brain barrier (BBB). Recent epidemiological studies have shown a strong statistical correlation between risk for ASD and either maternal or infantile atopic diseases, such as asthma, eczema, food allergies and food intolerance, all of which involve activation of mast cells (MCs). These unique tissue immune cells are located perivascularly in all tissues, including the thalamus and hypothalamus, which regulate emotions. MC-derived inflammatory and vasoactive mediators increase BBB permeability. Expression of the inflammatory molecules interleukin (IL-1β), IL-6, 1 L-17 and tumor necrosis factor (TNF) is increased in the brain, cerebrospinal fluid and serum of some patients with ASD, while NF-kB is activated in brain samples and stimulated peripheral blood immune cells of other patients; however, these molecules are not specific. Instead the peptide neurotensin is uniquely elevated in the serum of children with ASD, as is corticotropin-releasing hormone, secreted from the hypothalamus under stress. Both peptides trigger MC to release IL-6 and TNF, which in turn, stimulate microglia proliferation and activation, leading to disruption of neuronal connectivity. MC-derived IL-6 and TGFβ induce maturation of Th17 cells and MCs also secrete IL-17, which is increased in ASD. Serum IL-6 and TNF may define an ASD subgroup that benefits most from treatment with the natural flavonoid luteolin. Atopic diseases may create a phenotype susceptible to ASD and formulations targeting focal inflammation of the brain could have great promise in the treatment of ASD.

Association between Asthma and Autism Spectrum Disorder: A Meta-Analysis

Objective

We conducted a meta-analysis to summarize the evidence from epidemiological studies of the association between asthma and autism spectrum disorder (ASD).

Methods

A literature search was conducted using PubMed, Embase, and Cochrane library for studies published before February 2nd, 2016. Observational studies investigating the association between asthma and ASD were included. A random effects model was used to calculate the pooled risk estimates for the outcome. Subgroup analysis was used to explore potential sources of heterogeneity and publication bias was estimated using Begg's and Egger's tests.

Results

Ten studies encompassing 175,406 participants and 8,809 cases of ASD were included in this meta-analysis. In the cross-sectional studies, the prevalence of asthma in ASD was 20.4%, while the prevalence of asthma in controls was 15.4% (P < 0.001). The pooled odds ratio (OR) for the prevalence of asthma in ASD in the cross-sectional studies was 1.26 (95% confidence interval (CI): 0.98–1.61) (P = 0.07), with moderate heterogeneity (I² = 65.0%, P = 0.02) across studies. In the case-control studies, the pooled OR for the prevalence of asthma in ASD was 0.98 (95% CI: 0.68–1.43) (P = 0.94), and there was no evidence of an association between asthma and ASD. No evidence of significant publication bias on the association between asthma and ASD was found.

Conclusions

In conclusion, the results of this meta-analysis do not suggest an association between asthma and ASD. Further prospective studies ascertaining the association between asthma and ASD are warranted.

Increased production of IL-17 in children with autism spectrum disorders and co-morbid asthma

Inflammation and asthma have both been reported in some children with autism spectrum disorder (ASD). To further assess this connection, peripheral immune cells isolated from young children with ASD and typically developing (TD) controls and the production of cytokines IL-17, -13, and -4 assessed following ex vivo mitogen stimulation. Notably, IL-17 production was significantly higher following stimulation in ASD children compared to controls. Moreover, IL-17 was increased in ASD children with co-morbid asthma compared to controls with the same condition. In conclusion, children with ASD exhibited a differential response to T cell stimulation with elevated IL-17 production compared to controls.

Co-occurrence of autism and asthma in a nationally-representative sample of children in the United States

Few large epidemiological studies have examined the co-occurrence of autism and asthma. We performed a cross-sectional study to examine this association using the 2007 National Survey of Children's Health dataset (n = 77,951). We controlled for confounders and tested for autism-secondhand smoke interaction. Prevalence of asthma and autism were 14.5 % (n = 11,335) and 1.81 % (n = 1,412) respectively. Unadjusted odds ratio (OR) for asthma among autistic children was 1.35 (95 % CI 1.18-1.55). Adjusting for covariates (age, gender, body mass index, race, brain injury, secondhand smoke and socio-economic status) attenuated the OR to 1.19 (95 % CI 1.03-1.36). Autism-secondhand smoke interaction was insignificant (p = 0.38). Asthma is approximately 35 % more common in autistic children; screening may be an efficient approach to reduce risk of morbidity due to asthma.

Immune mediated conditions in autism spectrum disorders

We conducted a case-control study among members of Kaiser Permanente Northern California (KPNC) born between 1980 and 2003 to determine the prevalence of immune-mediated conditions in individuals with autism, investigate whether these conditions occur more often than expected, and explore the timing of onset relative to autism diagnosis. Cases were children and young adults with at least two autism diagnoses recorded in outpatient records (n=5565). Controls were children without autism randomly sampled at a ratio of 5 to 1, matched to cases on birth year, sex, and length of KPNC membership (n=27,825). The main outcomes - asthma, allergies, and autoimmune diseases - were identified from KPNC inpatient and outpatient databases. Chi-square tests were used to evaluate case-control differences. Allergies and autoimmune diseases were diagnosed significantly more often among children with autism than among controls (allergy: 20.6% vs. 17.7%, Crude odds ratio (OR)=1.22, 95% confidence interval (CI) 1.13-1.31; autoimmune disease: 1% vs. 0.76%, OR=1.36, 95% CI 1.01-1.83), and asthma was diagnosed significantly less often (13.7% vs. 15.9%; OR=0.83, 95% CI 0.76-0.90). Psoriasis occurred more than twice as often in cases than in controls (0.34% vs. 0.15%; OR=2.35, 95% CI 1.36-4.08). Our results support previous observations that children with autism have elevated prevalence of specific immune-related comorbidities.

Asthma and Allergies in Children With Autism Spectrum Disorders: Results From the CHARGE Study

Immune aberrations are often noted in children with autism spectrum disorder (ASD), but whether asthma and allergy are related to ASD is not well defined. This study examined asthma and allergies in association with ASD and phenotypic subsets. Participants were 560 children with confirmed ASD and 391 typically developing children from the CHildhood Autism Risks from Genetics and the Environment study. Maternally reported child asthma and allergy was compared between cases and controls, and in association with cognitive and behavioral test scores. Prevalence of asthma and overall allergies did not differ between cases and controls, but overall allergy in children with ASD was associated with higher stereotypy scores as measured by the Aberrant Behavior Checklist. In addition, reported food allergies were significantly associated with ASD (adjusted odds ratio = 2.23, 95% confidence interval 1.28, 3.89). Our results suggest food allergies and sensitivities may be more common in children with ASD, and that these issues may correlate with other behaviors.

Is atopy in early childhood a risk factor for ADHD and ASD? a longitudinal study

OBJECTIVE

Previous studies have found a temporal concordance in the increased prevalence of atopic diathesis/atopic diseases, attention-deficit hyperactivity disorder (ADHD), and autistic spectrum disorder (ASD) worldwide. But, the temporal association among these 3 distinct diseases is unknown.

METHOD

14,812 atopic subjects diagnosed with any atopic disease (asthma, atopic dermatitis, allergic rhinitis, or allergic conjunctivitis) before the age of 3 (atopic cohort) and 6944 non-atopic subjects with no lifetime atopic disease (non-atopic cohort), born between 1997 and 2000, were enrolled and followed to December 31, 2010 to identify the development of ADHD and ASD.

RESULTS

The presence of any atopic disease in early childhood increased the risk of developing ADHD (hazard ratio [HR]: 1.97) and ASD (HR: 3.40) in later life. Greater numbers of atopic comorbidities (4 comorbidities: ADHD: HR: 2.53; ASD: HR: 4.29) were significantly related to a greater risk of developing ADHD and ASD.

DISCUSSION

Atopic diathesis in early childhood elevated the risk of developing ADHD and ASD in later life, with the dose-dependent relationship of more atopic comorbidities with a greater likelihood of ADHD and ASD.

The need for a comprehensive molecular characterization of autism spectrum disorders

Autism spectrum disorders (ASD) are a heterogeneous group of disorders which have complex behavioural phenotypes. Although ASD is a highly heritable neuropsychiatric disorder, genetic research alone has not provided a profound understanding of the underlying causes. Recent developments using biochemical tools such as transcriptomics, proteomics and cellular models, will pave the way to gain new insights into the underlying pathological pathways. This review addresses the state-of-the-art in the search for molecular biomarkers for ASD. In particular, the most important findings in the biochemical field are highlighted and the need for establishing streamlined interaction between behavioural studies, genetics and proteomics is stressed. Eventually, these approaches will lead to suitable translational ASD models and, therefore, a better disease understanding which may facilitate novel drug discovery efforts in this challenging field.

Autism and EMF? Plausibility of a pathophysiological link part II

Autism spectrum conditions (ASCs) are defined behaviorally, but they also involve multileveled disturbances of underlying biology that find striking parallels in the physiological impacts of electromagnetic frequency and radiofrequency radiation exposures (EMF/RFR). Part I (Vol 776) of this paper reviewed the critical contributions pathophysiology may make to the etiology, pathogenesis and ongoing generation of behaviors currently defined as being core features of ASCs. We reviewed pathophysiological damage to core cellular processes that are associated both with ASCs and with biological effects of EMF/RFR exposures that contribute to chronically disrupted homeostasis. Many studies of people with ASCs have identified oxidative stress and evidence of free radical damage, cellular stress proteins, and deficiencies of antioxidants such as glutathione. Elevated intracellular calcium in ASCs may be due to genetics or may be downstream of inflammation or environmental exposures. Cell membrane lipids may be peroxidized, mitochondria may be dysfunctional, and various kinds of immune system disturbances are common. Brain oxidative stress and inflammation as well as measures consistent with blood-brain barrier and brain perfusion compromise have been documented. Part II of this paper documents how behaviors in ASCs may emerge from alterations of electrophysiological oscillatory synchronization, how EMF/RFR could contribute to these by de-tuning the organism, and policy implications of these vulnerabilities. It details evidence for mitochondrial dysfunction, immune system dysregulation, neuroinflammation and brain blood flow alterations, altered electrophysiology, disruption of electromagnetic signaling, synchrony, and sensory processing, de-tuning of the brain and organism, with autistic behaviors as emergent properties emanating from this pathophysiology. Changes in brain and autonomic nervous system electrophysiological function and sensory processing predominate, seizures are common, and sleep disruption is close to universal. All of these phenomena also occur with EMF/RFR exposure that can add to system overload ('allostatic load') in ASCs by increasing risk, and can worsen challenging biological problems and symptoms; conversely, reducing exposure might ameliorate symptoms of ASCs by reducing obstruction of physiological repair. Various vital but vulnerable mechanisms such as calcium channels may be disrupted by environmental agents, various genes associated with autism or the interaction of both. With dramatic increases in reported ASCs that are coincident in time with the deployment of wireless technologies, we need aggressive investigation of potential ASC-EMF/RFR links. The evidence is sufficient to warrant new public exposure standards benchmarked to low-intensity (non-thermal) exposure levels now known to be biologically disruptive, and strong, interim precautionary practices are advocated.

Antibodies against food antigens in patients with autistic spectrum disorders

PURPOSE

Immune system of some autistic patients could be abnormally triggered by gluten/casein assumption. The prevalence of antibodies to gliadin and milk proteins in autistic children with paired/impaired intestinal permeability and under dietary regimen either regular or restricted is reported.

METHODS

162 ASDs and 44 healthy children were investigated for intestinal permeability, tissue-transglutaminase (tTG), anti-endomysium antibodies (EMA)-IgA, and total mucosal IgA to exclude celiac disease; HLA-DQ2/-DQ8 haplotypes; total systemic antibodies (IgA, IgG, and IgE); specific systemic antibodies: α-gliadin (AGA-IgA and IgG), deamidated-gliadin-peptide (DGP-IgA and IgG), total specific gliadin IgG (all fractions: α, β, γ, and ω), β-lactoglobulin IgG, α-lactalbumin IgG, casein IgG; and milk IgE, casein IgE, gluten IgE,-lactoglobulin IgE, and α-lactalbumin IgE.

RESULTS

AGA-IgG and DPG-IgG titers resulted to be higher in ASDs compared to controls and are only partially influenced by diet regimen. Casein IgG titers resulted to be more frequently and significantly higher in ASDs than in controls. Intestinal permeability was increased in 25.6% of ASDs compared to 2.3% of healthy children. Systemic antibodies production was not influenced by paired/impaired intestinal permeability.

CONCLUSIONS

Immune system of a subgroup of ASDs is triggered by gluten and casein; this could be related either to AGA, DPG, and Casein IgG elevated production or to impaired intestinal barrier function.

A retrospective review of cytogenetic studies on methyl isocyanate with special reference to the Bhopal gas tragedy: is the next generation also at risk?

The world's worst industrial disaster, at Union Carbide, Bhopal, India, took place on 2-3 December 1984, leading to the leakage of poisonous methyl-isocyanate into the environment, causing thousands of deaths, pregnancy loss and for some, incapacitation for life. More than a quarter of a century later, the Indian Council of Medical Research undertook to redefine the abysmal consequences of the toxic gas exposure on the exposed population. This invigorated the interest of scientific community in the evaluation of the long-term effects, with reference to cytogenetic parameters. The thrust area was identified in terms of genetic disorders, low birth weight, developmental/growth disorders and congenital malformations. Also the impact on epigenetic factors, which may have contributed to variations in the functional expression of genes, was not negated, stimulating intense scientific research on in utero exposure and the progeny of the exposed population. To accomplish this mammoth task, molecular cytogenetic investigations must be undertaken in conjunction with conventional cytogenetics, using techniques such as FISH, Immuno-FISH, SKY and SNP analysis, to build up a cytogenetic database of the surviving population.

Low serum IgA and increased expression of CD23 on B lymphocytes in peripheral blood in children with regressive autism aged 3-6 years old

INTRODUCTION

Immune system dysfunction is considered to be one of many medical disorders found in children with autism. The primary objective of the study was to assess if blood tests reflecting humoral immunity (IgA, IgG, IgM, IgE) are useful in identifying children with regressive autism. The secondary objective was to evaluate a part of the cellular arm of immunity (CD4/CD25 Tregs, CD4/CD23 cells) in those children.

MATERIAL AND METHODS

Using a clinical case-control design, the systemic levels of immunoglobulins and lymphocyte subpopulations analysed by flow cytometry were compared in children aged 3-6 years old with a new diagnosis of regressive autism (n = 24; mean age: 4.25 ±1.70 years; male 23/24) and in sex- and age-matched healthy children (n = 24; aged 4.25 ±2.20 years; male 23/24).

RESULTS

The humoral immunity profile, described by three binary variables, IgA < 0.97 g/l, IgE > 36 IU/ml, and IgG > 6.3 g/l, with a sensitivity of 79% and a specificity of 83% (p < 0.0001), was able to identify children with autism. The highest risk of autism diagnosis was associated with IgA < 0.97g/l (OR - 23.0; p < 0.001). A higher number of CD19/CD23 was found in children diagnosed with autism than in the control group (36.82 ±6.72% vs. 18.20 ±3.95%; p < 0.02). No correlation between the number of CD23-positive cells and serum IgE levels was observed.

CONCLUSIONS

A subtle shift of serum immunoglobulins consisting of low-normal IgA and B cell activation expressed by an increase of CD23-positive cells may characterize children with regressive autism aged 3-6 years old.

Corticotropin-releasing hormone and extracellular mitochondria augment IgE-stimulated human mast-cell vascular endothelial growth factor release, which is inhibited by luteolin

BACKGROUND

Autism spectrum disorders (ASDs) are neurodevelopmental disorders characterized by varying degrees of dysfunctional social abilities, learning deficits, and stereotypic behaviors. Many patients with ASDs have 'allergy-like' symptoms and respond disproportionally to stress. We have previously shown that the peptide neurotensin (NT) is increased in the serum of young children with autism and that can stimulate extracellular secretion of mitochondrial (mt)DNA which was also increased in the serum of these children.

METHODS

Human mast cells were stimulated by corticotropin-releasing hormone (CRH), mitochondrial DNA, IgE/anti-IgE, either for 24 hours to measure vascular endothelial growth factor (VEGF) release by ELISA or for 6 hours or quantitative PCR.

RESULTS

CRH augmented IgE/anti-IgE-induced human mast-cell release of VEGF and it also induced the expression of IgE receptor (FcεRI) on mast cells. Moreover, sonicated mitochondria also augmented VEGF release, and this effect was blocked by the natural flavone luteolin.

CONCLUSION

These results indicate that stress and infection-mimicking extracellular mitochondrial components augment allergic inflammation that may be involved in the early pathogenesis of ASDs. Moreover, luteolin inhibits these processes and may be helpful in the treatment of ASDs.

Brief report: "allergic symptoms" in children with Autism Spectrum Disorders. More than meets the eye?

Many children with Autism Spectrum Disorders (ASD) have either family and/or personal history of "allergic symptomatology", often in the absence of positive skin or RAST tests. These symptoms may suggest mast cell activation by non-allergic triggers. Moreover, children with mastocytosis or mast cell activation syndrome (MCAS), a spectrum of rare diseases characterized by increased number of activated mast cells in many organs, appear to have ASD at a rate tenfold higher (1/10 children) than that of the general population (1/100 children). Mast cell activation by allergic, infectious, environmental and stress-related triggers, especially perinatally, would release pro-inflammatory and neurotoxic molecules. We speculate these could disrupt the gut-blood-brain barriers, thus contributing to brain inflammation and ASD pathogenesis. Increased mast cell responsiveness may define at least a subgroup of ASD subjects, who could benefit from inhibition of mast cell activation.

Mast cell activation and autism

Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by varying degrees of dysfunctional communication and social interactions, repetitive and stereotypic behaviors, as well as learning and sensory deficits. Despite the impressive rise in the prevalence of autism during the last two decades, there are few if any clues for its pathogenesis, early detection or treatment. Increasing evidence indicates high brain expression of pro-inflammatory cytokines and the presence of circulating antibodies against brain proteins. A number of papers, mostly based on parental reporting on their children's health problems, suggest that ASD children may present with "allergic-like" problems in the absence of elevated serum IgE and chronic urticaria. These findings suggest non-allergic mast cell activation, probably in response to environmental and stress triggers that could contribute to inflammation. In utero inflammation can lead to preterm labor and has itself been strongly associated with adverse neurodevelopmental outcomes. Premature babies have about four times higher risk of developing ASD and are also more vulnerable to infections, while delayed development of their gut-blood-brain barriers makes exposure to potential neurotoxins likely. Perinatal mast cell activation by infectious, stress-related, environmental or allergic triggers can lead to release of pro-inflammatory and neurotoxic molecules, thus contributing to brain inflammation and ASD pathogenesis, at least in a subgroup of ASD patients. This article is part of a Special Issue entitled: Mast cells in inflammation.

A proteomic investigation of B lymphocytes in an autistic family: a pilot study of exposure to natural rubber latex (NRL) may lead to autism

Autism is a multi-factorial neurodevelopmental disorder. We have investigated the molecular mechanism involved in a Chinese family with autism by a proteomic approach. Antibody chips containing 500 spots of human protein antibodies were used to screen for differentially expressed proteins in the peripheral B lymphocytes between autistic and non-autistic siblings in this family. Four proteins relevant to immuno-pathway, including IKKα that was up-regulated and Tyk2, EIF4G1 and PRKCI that were down-regulated, were identified differentially expressed in autistic versus non-autistic siblings. Western blot analysis and reverse transcription quantitative polymerase chain reaction validated the differential expression of these four proteins. Based on the function of these differentially expressed proteins, relevant studies on immunoglobulin E (IgE) level, nuclear factor kappa B signaling activation and cell cycle were conducted in both autistic and non-autistic children of this family. Considering the fact that the family members were in close contact with natural rubber latex (NRL) and that IgE-mediated cross-reactions could be triggered by Hevea brasiliensis (Hev-b) proteins in NRL, we hypothesize that immune reactions triggered by close contact with NRL might influence the functions of B lymphocytes by altering expression of certain proteins identified in our experiments thus contributing to the occurrence of autism.

Neurotensin is increased in serum of young children with autistic disorder

Autism spectrum disorders (ASD) are a group of pervasive neurodevelopmental disorders diagnosed in early childhood. They are associated with a set of "core symptoms" that include disabilities in social interaction skills, verbal and non-verbal communication, as well as repetitive and stereotypic behaviors. There is no definite pathogenetic mechanism or diagnostic tests. Many children with ASD also have "allergic-like" symptoms, but test negative implying mast cell activation by non-allergic triggers. We measured by Milliplex arrays serum levels of 3 neuropeptides that could stimulate mast cells in children with autistic disorder (n = 19; 16 males and 3 females; mean age 3.0 ± 0.4 years) and healthy, unrelated controls (n = 16; 13 males and 3 females; mean age 3 ± 1.2 years). Only neurotensin (NT) was significantly increased from 60.5 ± 6.0 pg/ml in controls to 105.6 ± 12.4 pg/ml in autistic disorder (p = 0.004). There was no statistically significant difference in the serum levels of β-endorphin or substance P (SP). NT could stimulate immune cells, especially mast cells, and/or have direct effects on brain inflammation and ASD.

The ScanBrit randomised, controlled, single-blind study of a gluten- and casein-free dietary intervention for children with autism spectrum disorders

There is increasing interest in the use of gluten- and casein-free diets for children with autism spectrum disorders (ASDs). We report results from a two-stage, 24-month, randomised, controlled trial incorporating an adaptive 'catch-up' design and interim analysis. Stage 1 of the trial saw 72 Danish children (aged 4 years to 10 years 11 months) assigned to diet (A) or non-diet (B) groups by stratified randomisation. Autism Diagnostic Observation Schedule (ADOS) and the Gilliam Autism Rating Scale (GARS) were used to assess core autism behaviours, Vineland Adaptive Behaviour Scales (VABS) to ascertain developmental level, and Attention-Deficit Hyperactivity Disorder - IV scale (ADHD-IV) to determine inattention and hyperactivity. Participants were tested at baseline, 8, and 12 months. Based on per protocol repeated measures analysis, data for 26 diet children and 29 controls were available at 12 months. At this point, there was a significant improvement to mean diet group scores (time*treatment interaction) on sub-domains of ADOS, GARS and ADHD-IV measures. Surpassing of predefined statistical thresholds as evidence of improvement in group A at 12 months sanctioned the re-assignment of group B participants to active dietary treatment. Stage 2 data for 18 group A and 17 group B participants were available at 24 months. Multiple scenario analysis based on inter- and intra-group comparisons showed some evidence of sustained clinical group improvements although possibly indicative of a plateau effect for intervention. Our results suggest that dietary intervention may positively affect developmental outcome for some children diagnosed with ASD. In the absence of a placebo condition to the current investigation, we are, however, unable to disqualify potential effects derived from intervention outside of dietary changes. Further studies are required to ascertain potential best- and non-responders to intervention. The study was registered with ClincialTrials.gov, number NCT00614198.

The immune system's role in the biology of autism

PURPOSE OF REVIEW

The following is a review of the most recent research concerning the potential role of immune system dysfunction in autism. This body of literature has expanded dramatically over the past few years as researchers continue to identify immune anomalies in individuals with autism.

RECENT FINDINGS

The most exciting of these recent findings is the discovery of autoantibodies targeting brain proteins in both children with autism and their mothers. In particular, circulating maternal autoantibodies directed toward fetal brain proteins are highly specific for autism. This finding has great potential as a biomarker for disease risk and may provide an avenue for future therapeutics and prevention. Additionally, data concerning the cellular immune system in children with autism suggest there may be a defect in signaling pathways that are shared by the immune and central nervous systems. Although studies to explore this hypothesis are ongoing, there is great interest in the commonalities between the neural and immune systems and their extensive interactions.

SUMMARY

In summary, the exciting research regarding the role of the immune system in autism spectrum disorders may have profound implications for diagnosis and treatment of this devastating disease.

Mercury induces inflammatory mediator release from human mast cells

Background

Mercury is known to be neurotoxic, but its effects on the immune system are less well known. Mast cells are involved in allergic reactions, but also in innate and acquired immunity, as well as in inflammation. Many patients with Autism Spectrum Disorders (ASD) have "allergic" symptoms; moreover, the prevalence of ASD in patients with mastocytosis, characterized by numerous hyperactive mast cells in most tissues, is 10-fold higher than the general population suggesting mast cell involvement. We, therefore, investigated the effect of mercuric chloride (HgCl₂) on human mast cell activation.

Methods

Human leukemic cultured LAD2 mast cells and normal human umbilical cord blood-derived cultured mast cells (hCBMCs) were stimulated by HgCl2 (0.1-10 μM) for either 10 min for beta-hexosaminidase release or 24 hr for measuring vascular endothelial growth factor (VEGF) and IL-6 release by ELISA.

Results

HgCl₂ induced a 2-fold increase in β-hexosaminidase release, and also significant VEGF release at 0.1 and 1 μM (311 ± 32 pg/10⁶ cells and 443 ± 143 pg/10⁶ cells, respectively) from LAD2 mast cells compared to control cells (227 ± 17 pg/10⁶ cells, n = 5, p < 0.05). Addition of HgCl₂ (0.1 μM) to the proinflammatory neuropeptide substance P (SP, 0.1 μM) had synergestic action in inducing VEGF from LAD2 mast cells. HgCl₂ also stimulated significant VEGF release (360 ± 100 pg/10⁶ cells at 1 μM, n = 5, p < 0.05) from hCBMCs compared to control cells (182 ± 57 pg/10⁶ cells), and IL-6 release (466 ± 57 pg/10⁶ cells at 0.1 μM) compared to untreated cells (13 ± 25 pg/10⁶ cells, n = 5, p < 0.05). Addition of HgCl₂ (0.1 μM) to SP (5 μM) further increased IL-6 release.

Conclusions

HgCl₂ stimulates VEGF and IL-6 release from human mast cells. This phenomenon could disrupt the blood-brain-barrier and permit brain inflammation. As a result, the findings of the present study provide a biological mechanism for how low levels of mercury may contribute to ASD pathogenesis.

Update on autism: a review of 1300 reports published in 2008

This publication, by reviewing 1300 studies published on autism in 2008, represents an update on this topic. Results include possible parental influences, maternal conditions, and studies on genes and chromosomes. Possible etiological factors involve the "extreme male brain," defects in the mirror neuron system, vaccines, underconnectivity, disorders of central coherence, and many other more specific etiologies. Assessments or tests for autism are also reviewed. Characteristics of autistic individuals include repetitive behavior, language disorders, sleep disturbances, social problems, joint attention disorders, seizures, allergic reactions, and various behavioral changes. Cognitive changes involve IQ, reasoning, and verbal and language disorders. The savant syndrome is a fascinating phenomenon, at times seen in autistic individuals. Neurophysiological and neuroanatomical changes are also reviewed, as are comorbid conditions. Finally, treatment involves various medications including risperidone, ziprasidone, and antipsychotic drugs, as well as different procedures such as magnetic stimulation, acupuncture, and hyperbaric oxygen therapy. As mentioned in the 2007 survey, nearly every conceivable problem that a child can have may be found in these unfortunate children and nearly every conceivable etiology has been mentioned to account for this serious disorder.

Autism: an emerging 'neuroimmune disorder' in search of therapy

BACKGROUND

Autism spectrum disorders (ASDs) are neurodevelopmental disorders characterized by difficulties in communication and by repetitive and stereotypic behaviors, as well as by social impairment, attention, cognitive, and learning defects. ASDs present in early childhood and their prevalence has increased significantly to 1/150 children. Despite a number of theories, the actual reasons for this increase are still not clear. There is no reliable screening test, and no definite pathogenesis or curative therapy. Consequently, there is a major gap hampering development of effective treatments.

OBJECTIVE

To review recent publications on ASDs pathogenesis and treatment with emphasis on neuroimmune processes and new therapeutic approaches.

METHODS

Mostly original papers (450) on epidemiology, possible pathogenesis or treatment of ASDs in Medline from 1990 to May 2009 were reviewed. All authors contributed to this review.

RESULTS/CONCLUSION

Increased oxidative stress and immune dysregulation are present in ASDs. Mast-cell activation may contribute to gut-blood-brain barrier disruption and brain inflammation. No effective treatments have emerged. Well-designed clinical trials with nonpsychotropic drugs were few and ASD characteristics varied considerably, making conclusions difficult. Psychotropic drugs are often used for stereotypic and aggressive behaviors. Unique combinations with antioxidant and anti-inflammatory flavonoids hold promise. New potential translational research areas and possible treatments are suggested.

Autism Spectrum Disorders and Mastocytosis

Autism Spectrum Disorders (ASD) are diagnosed in early childhood and include Autism, Asperger's disorder and Pervasive neurodevelopmental disorder - not otherwise specified (PDD-NOS, or atypical autism). ASD are associated with varying degrees of dysfunctional communication and social skills, repetitive and stereotypic behaviors, as well as attention and learning disabilities. Most ASD patients also have food intolerance and other allergic symptomatology indicative of mast cell activation. The number of ASD cases have increased over the last decade to 1/100, but there is no definite pathogenesis or curative therapy. We report that the apparent prevalence of ASD in patients with mastocytosis, a rare disease occuring in 1/4,000 children and characterized by an increased number of hypersensitive mast cells in many organs, is about 1/10 or 10 times higher than the general population. A child with skin mastocytosis [urticaria pigmentosa, (UP)] and regressive autism is presented to illustrate the point. Allergic, infectious, neuroimmune and environmental triggers may activate mast cells to release vasoactive, inflammatory and neurotoxic molecules. These could disrupt the gut-blood-brain-barriers (BBB), and/or activate susceptibility genes, thus contributing to brain inflammation and ASD.

Food allergy and autism spectrum disorders: is there a link?

Gastrointestinal (GI) symptoms are common comorbidities in children with autism spectrum disorders (ASDs). Parents often attribute these GI symptoms to food allergy (FA), although an evaluation for IgE-mediated FA is often unrevealing. Our previous studies indicated a high prevalence of non-IgE-mediated FA in young children with ASDs. Therefore, non-IgE-mediated FA may account for some but not all GI symptoms observed in children with ASDs. This raises the question of what treatment measures are applicable to ASD children with GI symptoms. A wide variety of dietary supplements and dietary intervention measures for ASD children have been promoted by medical professionals practicing complementary and alternative medicine despite the lack of rigorous scientific validation in most instances. This review summarizes possible (or proposed) etiologies of GI symptoms in ASD children and discusses risks and possible benefits of intervention measures promoted by complementary and alternative practitioners, with emphasis on FA.

Novel therapeutic targets for autism

Autism spectrum disorders (ASDs) are pervasive neurodevelopmental disorders, diagnosed in early childhood when acquired skills are lost or the acquisition of new skills becomes delayed. ASDs are associated with varying degrees of dysfunctional communication and social skills, in addition to repetitive and stereotypic behaviors. The diagnosis has increased considerably to approximately one in 180 people, but it is not clear whether this is because of a higher prevalence of the disorder, improved awareness by clinicians or a combination of both. There are no defined mechanisms of pathogenesis or curative therapy presently available. Oxidative stress, overactivation of the hypothalamic-pituitary-adrenal axis and increased gut-blood-brain-barrier permeability might be involved. The scope of this article is to integrate these findings and present the opinion that non-allergic activation of gastrointestinal and brain mast cells could contribute to many of the pathologic findings and provide unique targets for ASD therapy. We make suggestions for new research directives and possible novel therapies from readily available molecules.