Gastrointestinal abnormalities in children with autistic disorder

Bone density in peripubertal boys with autism spectrum disorders

We determined whether bone mineral density (BMD) is lower in boys with autism spectrum disorders (ASD) than controls, and also assessed variables that may affect BMD in ASD. BMD was measured using dual energy X-ray absorptiometry (DXA) in 18 boys with ASD and 19 controls 8-14 years old. Boys with ASD had lower BMD Z-scores at the spine, hip and femoral neck, and differences at the hip and femoral neck persisted after controlling for maturity and BMI. Vitamin D intake from food and in serum were lower in ASD subjects, as was exercise activity. We conclude that BMD is lower in peripubertal boys with ASD and may be associated with impaired vitamin D status and lower exercise activity.

Immune Response to Dietary Proteins, Gliadin and Cerebellar Peptides in Children with Autism

The mechanisms behind autoimmune reaction to nervous system antigens in autism are not understood. We assessed the reactivity of sera from 50 autism patients and 50 healthy controls to specific peptides from gliadin and the cerebellum. A significant percentage of autism patients showed elevations in antibodies against gliadin and cerebellar peptides simultaneously. For examining cross-reaction between dietary proteins and cerebellar antigens, antibodies were prepared in rabbits, and binding of rabbit anti-gliadin, anti-cerebellar peptides, anti-MBP, anti-milk, anti-egg, anti-soy and anti-corn to either gliadin- or cerebellar-antigen-coated wells was measured. In comparison to anti-gliadin peptide binding to gliadin peptide at 100%, the reaction of anti-cerebellar peptide to gliadin peptide was 22%, whereas the binding of anti-myelin basic protein (MBP), anti-milk, anti-egg and anti-soy to gliadin was less than 10%. Further examination of rabbit anti-gliadin (EQVPLVQQ) and anti-cerebellar (EDVPLLED) 8 amino acid (AA) peptides with human serum albumin (HSA) and an unrelated peptide showed no binding, but the reaction of these antibodies with both the cerebellar and gliadin peptides was greater than 60%. This cross-reaction was further confirmed by DOT-immunoblot and inhibition studies. We conclude that a subgroup of patients with autism produce antibodies against Purkinje cells and gliadin peptides, which may be responsible for some of the neurological symptoms in autism.

Reduced incidence of Prevotella and other fermenters in intestinal microflora of autistic children

High proportions of autistic children suffer from gastrointestinal (GI) disorders, implying a link between autism and abnormalities in gut microbial functions. Increasing evidence from recent high-throughput sequencing analyses indicates that disturbances in composition and diversity of gut microbiome are associated with various disease conditions. However, microbiome-level studies on autism are limited and mostly focused on pathogenic bacteria. Therefore, here we aimed to define systemic changes in gut microbiome associated with autism and autism-related GI problems. We recruited 20 neurotypical and 20 autistic children accompanied by a survey of both autistic severity and GI symptoms. By pyrosequencing the V2/V3 regions in bacterial 16S rDNA from fecal DNA samples, we compared gut microbiomes of GI symptom-free neurotypical children with those of autistic children mostly presenting GI symptoms. Unexpectedly, the presence of autistic symptoms, rather than the severity of GI symptoms, was associated with less diverse gut microbiomes. Further, rigorous statistical tests with multiple testing corrections showed significantly lower abundances of the genera Prevotella, Coprococcus, and unclassified Veillonellaceae in autistic samples. These are intriguingly versatile carbohydrate-degrading and/or fermenting bacteria, suggesting a potential influence of unusual diet patterns observed in autistic children. However, multivariate analyses showed that autism-related changes in both overall diversity and individual genus abundances were correlated with the presence of autistic symptoms but not with their diet patterns. Taken together, autism and accompanying GI symptoms were characterized by distinct and less diverse gut microbial compositions with lower levels of Prevotella, Coprococcus, and unclassified Veillonellaceae.

Possible ameliorative effect of breastfeeding and the uptake of human colostrum against coeliac disease in autistic rats

AIM: To examine the possible ameliorative effect of breastfeeding and the uptake of human colostrum against coeliac disease in autistic rats.

METHODS: Female rats were fed a standard diet and received a single intraperitoneal injection of 600 mg/kg sodium valproate on day 12.5 after conception. In study 1, neonatal rats were randomly subjected to blood tests to investigate autism. In study 2, the 1^st group was fed by the mother after an injection of interferon-γ (IFN-γ) and administration of gliadin. The pups in the 2^nd group were prevented from accessing maternal milk, injected IFN-γ, administered gliadin, and hand-fed human colostrum. The normal littermates fed by the table mothers were injected with physiological saline and served as normal controls in this study.

RESULTS: The protein concentration was higher in group 2 than in group 1 in the duodenum (161.6 ± 9 and 135.4 ± 7 mg/g of tissue, respectively, P < 0.01). A significant increase (P < 0.001) in body weight was detected in human colostrum-treated pups on post natal day (PND) 7 and 21 vs suckling pups in group 1. A delay in eye opening was noticed in the treated rats in group 1 on PND 13 compared with the control group and group 2. Administration of a single intraperitoneal injection of 600 mg/kg sodium valproate on day 12.5 after conception resulted in significantly reduced calcium and vitamin D levels in study 1 compared with the control groups (P < 0.001). However, human colostrum uptake inhibited increases in the level of transglutaminase antibody in autistic pups with coeliac disease.

CONCLUSION: The effects of early-life nutrition and human colostrum on the functional maturation of the duodenal villi in autistic rats with coeliac disease that might limit or prevent the coeliac risk with autism.

Nutritional status survey of children with autism and typically developing children aged 4-6 years in Heilongjiang Province, China

Autism is a neurodevelopmental disability that may affect nutritional management of children with autism. This study aimed to compare the nutritional status of children with autism with that of typically developing children (aged 4–6 years) in China. Nutritional status was assessed by means of nutritional data, anthropometric data, biochemical assessment, physical examination for nutrient deficiencies and providing a questionnaire to parents. A total of fifty-three children with autism and fifty-three typically developing children were enrolled in this study. The parents were asked to complete the questionnaire regarding the eating behaviour and gastrointestinal symptoms of their children. They were also asked to provide a 3 d food diary. Children with autism exhibited several abnormalities in terms of eating behaviour and gastrointestinal symptoms. The levels of vitamins A and B₆, Zn and Ca intakes were <80 % of the dietary reference intakes in both groups. In addition, the proportions of vitamin C and Ca intake deficiencies in the autism group were significantly higher than those in the control group. Serum Zn level was less than the normal reference range in both the groups. Serum Ca, vitamin A and folate levels in children with autism were significantly lower when compared with children without autism. According to the anthropometric data, the mean BMI, weight-for-height Z-score (Z_WH) and BMI for age Z-score (Z_BMIA) of children with autism were significantly higher than those of the typically developing children. Thus, nutritional inadequacies were observed in children with autism and typically developing children in China, which were, however, more pronounced among children with autism.

Identification of unique gene expression profile in children with regressive autism spectrum disorder (ASD) and ileocolitis

Gastrointestinal symptoms are common in children with autism spectrum disorder (ASD) and are often associated with mucosal inflammatory infiltrates of the small and large intestine. Although distinct histologic and immunohistochemical properties of this inflammatory infiltrate have been previously described in this ASD(GI) group, molecular characterization of these lesions has not been reported. In this study we utilize transcriptome profiling of gastrointestinal mucosal biopsy tissue from ASD(GI) children and three non-ASD control groups (Crohn's disease, ulcerative colitis, and histologically normal) in an effort to determine if there is a gene expression profile unique to the ASD(GI) group. Comparison of differentially expressed transcripts between the groups demonstrated that non-pathologic (normal) tissue segregated almost completely from inflamed tissue in all cases. Gene expression profiles in intestinal biopsy tissue from patients with Crohn's disease, ulcerative colitis, and ASD(GI), while having significant overlap with each other, also showed distinctive features for each group. Taken together, these results demonstrate that ASD(GI) children have a gastrointestinal mucosal molecular profile that overlaps significantly with known inflammatory bowel disease (IBD), yet has distinctive features that further supports the presence of an ASD-associated IBD variant, or, alternatively, a prodromal phase of typical inflammatory bowel disease. Although we report qPCR confirmation of representative differentially expressed transcripts determined initially by microarray, these findings may be considered preliminary to the extent that they require further confirmation in a validation cohort.

Oxytocin modulates mTORC1 pathway in the gut

Our recent findings of a weaning-related pattern of oxytocin (OT) and OT receptor (OTR) expression in the rat enteric nervous system and in villus-crypt enterocytes, together with the known high level and stability of OT in breast milk support that OT may play a role in gut function and development. We previously described a biphasic dose-response of the PI3K/Akt pathway in gut cells treated with OT. Activation peaked at 62.5 nM OT (30 min) and coincided with OTR internalization. Here we use automated Western blotting to further explore OT-elicited changes in Akt and pAkt(T308), as well as in downstream substrates p70 S6 kinase-1 (S6K1) and eIF-4E binding protein 1 (4E-BP1). Relative to fresh growth medium (FGM) alone, our results showed OT in FGM reduced the abundance and phosphorylation of S6K1 and the phosphorylation of 4E-BP1, both substrates of mammalian target of rapamycin complex 1 (mTORC1). Phosphorylation of mTORC1 regulator, Raptor(S792), was increased by high and low OT concentrations, with predicted inhibitory effects on mTORC1. OT thus downregulates anabolic effects induced by FGM activity catalyzed by mTORC1. OT is a regulator of the PI3K/Akt/mTORC1 pathway in Caco2BB cells and may modulate translation in gut cells.

Metabolic perturbance in autism spectrum disorders: a metabolomics study

Autism spectrum disorders (ASD) are a group of biological disorders with associated metabolic derangement. This study aimed to identify a pattern of metabolic perturbance in ASD using metabolomics in urinary specimens from 48 children with ASD and 53 age matched controls. Using a combination of liquid- and gas-chromatography-based mass spectrometry, we detected the levels of 82 metabolites (53 of which were increased) that were significantly altered between the ASD and the control groups using osmolality normalized data. Pattern analysis showed that the levels of several amino acids such as glycine, serine, threonine, alanine, histidine, glutamyl amino acids and the organic acid, taurine were significantly (p≤0.05) lower in ASD children. The levels of antioxidants such as carnosine were also reduced in ASD (p=0.054). Furthermore, several gut bacterial metabolites were significantly altered in ASD children who had gastrointestinal dysfunction. Overall, this study detected abnormal amino acid metabolism, increased oxidative stress, and altered gut microbiomes in ASD. The relationship of altered gut microbial co-metabolism and the disrupted metabolisms requires further investigation.

Brief report: Association between behavioral features and gastrointestinal problems among children with autism spectrum disorder

Recent reports suggest certain behaviors among children with autism spectrum disorders (ASD) may indicate underlying gastro-intestinal (GI) problems, and that the presence of these behaviors may help alert primary care providers to the need to evaluate a child with ASD for GI problems. The purpose of this population-based study of 487 children with ASD, including 35 (7.2%) with a medically documented history of GI problems, was to compare behavioral features of children with and without a history of GI problems. Unusual sleeping or eating habits and oppositional behavior were significantly associated with GI problems. These behaviors, however, were frequent in both children with and without GI problems, suggesting they may have limited utility in a screening capacity for GI problems.

Modeling autism: a systems biology approach

Autism is the fastest growing developmental disorder in the world today. The prevalence of autism in the US has risen from 1 in 2500 in 1970 to 1 in 88 children today. People with autism present with repetitive movements and with social and communication impairments. These impairments can range from mild to profound. The estimated total lifetime societal cost of caring for one individual with autism is $3.2 million US dollars. With the rapid growth in this disorder and the great expense of caring for those with autism, it is imperative for both individuals and society that techniques be developed to model and understand autism. There is increasing evidence that those individuals diagnosed with autism present with highly diverse set of abnormalities affecting multiple systems of the body. To this date, little to no work has been done using a whole body systems biology approach to model the characteristics of this disorder. Identification and modelling of these systems might lead to new and improved treatment protocols, better diagnosis and treatment of the affected systems, which might lead to improved quality of life by themselves, and, in addition, might also help the core symptoms of autism due to the potential interconnections between the brain and nervous system with all these other systems being modeled. This paper first reviews research which shows that autism impacts many systems in the body, including the metabolic, mitochondrial, immunological, gastrointestinal and the neurological. These systems interact in complex and highly interdependent ways. Many of these disturbances have effects in most of the systems of the body. In particular, clinical evidence exists for increased oxidative stress, inflammation, and immune and mitochondrial dysfunction which can affect almost every cell in the body. Three promising research areas are discussed, hierarchical, subgroup analysis and modeling over time. This paper reviews some of the systems disturbed in autism and suggests several systems biology research areas. Autism poses a rich test bed for systems biology modeling techniques.

Molecular characterisation of gastrointestinal microbiota of children with autism (with and without gastrointestinal dysfunction) and their neurotypical siblings

Many children with autism spectrum disorders (ASDs) suffer from gastrointestinal problems such as diarrhoea, constipation and abdominal pain. This has stimulated investigations into possible abnormalities of intestinal microbiota in autistic patients. Therefore, we designed this study to identify differences (and/or similarities) in the microbiota of children with autism (without gastrointestinal dysfunction: n = 23; with gastrointestinal dysfunction: n = 28) and their neurotypical siblings (n = 53) who share a similar environment using bacterial tag-encoded FLX amplicon pyrosequencing. Regardless of the diagnosis and sociodemographic characteristics, overall, Firmicutes (70%), Bacteroidetes (20%) and Proteobacteria (4%) were the most dominant phyla in samples. Results did not indicate clinically meaningful differences between groups. The data do not support the hypothesis that the gastrointestinal microbiota of children with ASD plays a role in the symptomatology of ASD. Other explanations for the gastrointestinal dysfunction in this population should be considered including elevated anxiety and self-restricted diets.

Peptides' role in autism with emphasis on exorphins

Problem

The nature of the peptides found increased in urine from autism needs verification of their structure, especially those that show opioid activity.

Methods

The peptides were separated on reverse phase C-18 HPLC in Trifluoroacetic acid–acetonitril gradients. Peaks eluting where synthetic opioids appear, and peaks that are common to most autistic children were analyzed by mass spectrometry and fragmentation pattern on a quadropole mass-spectrometer.

Results

We could demonstrate exorphins in the urine from autistic children, and their length varied from one patient to the next.

Conclusion

Exorphins are found in urine of autistic children and may account for their symptoms.

Short-chain fatty acid fermentation products of the gut microbiome: implications in autism spectrum disorders

Recent evidence suggests potential, but unproven, links between dietary, metabolic, infective, and gastrointestinal factors and the behavioral exacerbations and remissions of autism spectrum disorders (ASDs). Propionic acid (PPA) and its related short-chain fatty acids (SCFAs) are fermentation products of ASD-associated bacteria (Clostridia, Bacteriodetes, Desulfovibrio). SCFAs represent a group of compounds derived from the host microbiome that are plausibly linked to ASDs and can induce widespread effects on gut, brain, and behavior. Intraventricular administration of PPA and SCFAs in rats induces abnormal motor movements, repetitive interests, electrographic changes, cognitive deficits, perseveration, and impaired social interactions. The brain tissue of PPA-treated rats shows a number of ASD-linked neurochemical changes, including innate neuroinflammation, increased oxidative stress, glutathione depletion, and altered phospholipid/acylcarnitine profiles. These directly or indirectly contribute to acquired mitochondrial dysfunction via impairment in carnitine-dependent pathways, consistent with findings in patients with ASDs. Of note, common antibiotics may impair carnitine-dependent processes by altering gut flora favoring PPA-producing bacteria and by directly inhibiting carnitine transport across the gut. Human populations that are partial metabolizers of PPA are more common than previously thought. PPA has further bioactive effects on neurotransmitter systems, intracellular acidification/calcium release, fatty acid metabolism, gap junction gating, immune function, and alteration of gene expression that warrant further exploration. These findings are consistent with the symptoms and proposed underlying mechanisms of ASDs and support the use of PPA infusions in rats as a valid animal model of the condition. Collectively, this offers further support that gut-derived factors, such as dietary or enteric bacterially produced SCFAs, may be plausible environmental agents that can trigger ASDs or ASD-related behaviors and deserve further exploration in basic science, agriculture, and clinical medicine.

Investigation of autism comorbidities and associations in a school-based community sample

PROBLEM

Individuals with autism spectrum disorders (ASDs) have at least as many comorbidities as individuals with typical development may show, but sometimes with different presentations.

METHODS

The study used a school-based health survey related to children diagnosed with ASD in Tehran to determine the possibility of comorbid conditions. Ninety-one children and adolescents with ASD between the ages of 6 and 14 years were included in the study, all from five schools of different districts of the city, using stratified random sampling. All of the subjects had received a clinical diagnosis of ASD (autism, Asperger, and pervasive developmental disorder-not otherwise specified) by a child neurologist or psychiatrist. All of the schools had registered the subjects and were restricted to those with high-functioning forms of ASD, and none were identified with co-occurring mental retardation.

FINDINGS

Results indicated that 72.5% had at least one comorbid condition. There was a trend of higher severity in autism symptoms in subjects with comorbidity. Results showed that attention-deficit/hyperactivity disorder and epileptic disorders were the leading comorbidity in respective categories.

CONCLUSION

Autistic individuals should be monitored regarding their comorbid profiles, with an emphasis on female subjects and those with more severe symptoms. Clinically, the current study has implications for school healthcare providers, including nurses, in addition to researchers and practitioners working with children diagnosed with ASDs.

The co-morbidity burden of children and young adults with autism spectrum disorders

OBJECTIVES

Use electronic health records Autism Spectrum Disorder (ASD) to assess the comorbidity burden of ASD in children and young adults.

STUDY DESIGN

A retrospective prevalence study was performed using a distributed query system across three general hospitals and one pediatric hospital. Over 14,000 individuals under age 35 with ASD were characterized by their co-morbidities and conversely, the prevalence of ASD within these comorbidities was measured. The comorbidity prevalence of the younger (Age<18 years) and older (Age 18-34 years) individuals with ASD was compared.

RESULTS

19.44% of ASD patients had epilepsy as compared to 2.19% in the overall hospital population (95% confidence interval for difference in percentages 13.58-14.69%), 2.43% of ASD with schizophrenia vs. 0.24% in the hospital population (95% CI 1.89-2.39%), inflammatory bowel disease (IBD) 0.83% vs. 0.54% (95% CI 0.13-0.43%), bowel disorders (without IBD) 11.74% vs. 4.5% (95% CI 5.72-6.68%), CNS/cranial anomalies 12.45% vs. 1.19% (95% CI 9.41-10.38%), diabetes mellitus type I (DM1) 0.79% vs. 0.34% (95% CI 0.3-0.6%), muscular dystrophy 0.47% vs 0.05% (95% CI 0.26-0.49%), sleep disorders 1.12% vs. 0.14% (95% CI 0.79-1.14%). Autoimmune disorders (excluding DM1 and IBD) were not significantly different at 0.67% vs. 0.68% (95% CI -0.14-0.13%). Three of the studied comorbidities increased significantly when comparing ages 0-17 vs 18-34 with p<0.001: Schizophrenia (1.43% vs. 8.76%), diabetes mellitus type I (0.67% vs. 2.08%), IBD (0.68% vs. 1.99%) whereas sleeping disorders, bowel disorders (without IBD) and epilepsy did not change significantly.

CONCLUSIONS

The comorbidities of ASD encompass disease states that are significantly overrepresented in ASD with respect to even the patient populations of tertiary health centers. This burden of comorbidities goes well beyond those routinely managed in developmental medicine centers and requires broad multidisciplinary management that payors and providers will have to plan for.

A review of candidate urinary biomarkers for autism spectrum disorder

CONTEXT

Autism is a complex, heterogeneous neurodevelopmental condition with a strong genetic component potentially impacted by various environmental factors influencing susceptibility. There are no reliable laboratory tests available to confirm an autism diagnosis.

OBJECTIVE

To examine the published literature and identify putative urinary biomarkers of autism.

METHODS

A comprehensive literature search was conducted using electronic bibliographic databases.

RESULTS

Putative autism biomarkers were identified that could be categorized according to the key theories that exist regarding the etiology of autism: gastrointestinal factors, immune dysregulation, heavy metal toxicity, neurotransmitter abnormalities, and oxidative stress.

CONCLUSION

There is scope for specific urinary biomarkers to be useful for identification of autistic metabolic phenotypes.

Role of endocrine factors in autistic spectrum disorders

It is possible that autism spectrum disorders (ASDs) have a multifactorial cause along with more than one predisposing and perpetuating factor, all of which culminate in expression of these disorders. Endocrine and neuropeptide factors are among the list of possible etiologic or predisposing contenders. The search for an endocrine model to explain the etiopathogenesis of ASD is a new endeavor. In this article, the authors look at some of the emerging literature that is available regarding any possible relationship between the endocrine hormones and factors and whether it can possibly be etiologic or merely coincidental with autism and ASDs.

Application of novel PCR-based methods for detection, quantitation, and phylogenetic characterization of Sutterella species in intestinal biopsy samples from children with autism and gastrointestinal disturbances

Gastrointestinal disturbances are commonly reported in children with autism and may be associated with compositional changes in intestinal bacteria. In a previous report, we surveyed intestinal microbiota in ileal and cecal biopsy samples from children with autism and gastrointestinal dysfunction (AUT-GI) and children with only gastrointestinal dysfunction (Control-GI). Our results demonstrated the presence of members of the family Alcaligenaceae in some AUT-GI children, while no Control-GI children had Alcaligenaceae sequences. Here we demonstrate that increased levels of Alcaligenaceae in intestinal biopsy samples from AUT-GI children result from the presence of high levels of members of the genus Sutterella. We also report the first Sutterella-specific PCR assays for detecting, quantitating, and genotyping Sutterella species in biological and environmental samples. Sutterella 16S rRNA gene sequences were found in 12 of 23 AUT-GI children but in none of 9 Control-GI children. Phylogenetic analysis revealed a predominance of either Sutterella wadsworthensis or Sutterella stercoricanis in 11 of the individual Sutterella-positive AUT-GI patients; in one AUT-GI patient, Sutterella sequences were obtained that could not be given a species-level classification based on the 16S rRNA gene sequences of known Sutterella isolates. Western immunoblots revealed plasma IgG or IgM antibody reactivity to Sutterella wadsworthensis antigens in 11 AUT-GI patients, 8 of whom were also PCR positive, indicating the presence of an immune response to Sutterella in some children.

IMPORTANCE

Autism spectrum disorders affect ~1% of the population. Many children with autism have gastrointestinal (GI) disturbances that can complicate clinical management and contribute to behavioral problems. Understanding the molecular and microbial underpinnings of these GI issues is of paramount importance for elucidating pathogenesis, rendering diagnosis, and administering informed treatment. Here we describe an association between high levels of intestinal, mucoepithelial-associated Sutterella species and GI disturbances in children with autism. These findings elevate this little-recognized bacterium to the forefront by demonstrating that Sutterella is a major component of the microbiota in over half of children with autism and gastrointestinal dysfunction (AUT-GI) and is absent in children with only gastrointestinal dysfunction (Control-GI) evaluated in this study. Furthermore, these findings bring into question the role Sutterella plays in the human microbiota in health and disease. With the Sutterella-specific molecular assays described here, some of these questions can begin to be addressed.

Impaired carbohydrate digestion and transport and mucosal dysbiosis in the intestines of children with autism and gastrointestinal disturbances

Gastrointestinal disturbances are commonly reported in children with autism, complicate clinical management, and may contribute to behavioral impairment. Reports of deficiencies in disaccharidase enzymatic activity and of beneficial responses to probiotic and dietary therapies led us to survey gene expression and the mucoepithelial microbiota in intestinal biopsies from children with autism and gastrointestinal disease and children with gastrointestinal disease alone. Ileal transcripts encoding disaccharidases and hexose transporters were deficient in children with autism, indicating impairment of the primary pathway for carbohydrate digestion and transport in enterocytes. Deficient expression of these enzymes and transporters was associated with expression of the intestinal transcription factor, CDX2. Metagenomic analysis of intestinal bacteria revealed compositional dysbiosis manifest as decreases in Bacteroidetes, increases in the ratio of Firmicutes to Bacteroidetes, and increases in Betaproteobacteria. Expression levels of disaccharidases and transporters were associated with the abundance of affected bacterial phylotypes. These results indicate a relationship between human intestinal gene expression and bacterial community structure and may provide insights into the pathophysiology of gastrointestinal disturbances in children with autism.

Low relative abundances of the mucolytic bacterium Akkermansia muciniphila and Bifidobacterium spp. in feces of children with autism

Gastrointestinal disturbance is frequently reported for individuals with autism. We used quantitative real-time PCR analysis to quantify fecal bacteria that could influence gastrointestinal health in children with and without autism. Lower relative abundances of Bifidobacteria species and the mucolytic bacterium Akkermansia muciniphila were found in children with autism, the latter suggesting mucus barrier changes.

Effectiveness of nutritional supplements for reducing symptoms in autism-spectrum disorder: a case report

OBJECTIVE

This report presents a case of a 9-year-old boy with autism that responded positively to nutritional supplements.

METHODS

The supplements were dimethylglycine and a combination of a large dose of vitamin B6 (pyridoxal HCl) and magnesium. The Autism Treatment Evaluation Checklist (ATEC) was used for outcome assessment and administered by 2 of his family members both before the nutritional supplements and 5 months into the supplements, thereby referred to as pretest and post-test, respectively. Two (2) assessors independently performed evaluations. The ATEC evaluates four areas: communication, sociability, sensory/cognitive awareness, and behavior. The lower the scores are, the less severe the symptoms are.

RESULTS

The ATEC evaluations by 2 independent assessors showed that the changes in total ATEC were from 63 at pretest to 33 at post-test, and from 64 at pretest to 30 at post-test, respectively. These changes represented reductions of 47.6% and 53.1%. A strong inter-rater reliability was demonstrated, with an intraclass correlation coefficient of 0.988. The school teachers also noticed improvements in various areas consistent with the ATEC evaluations.

CONCLUSIONS

Although the reported findings cannot be generalized, this case report provides useful preliminary evidence to an accumulating body of literature supporting the theory and efficacies of nutritional supplements in autism-spectrum disorders.

Controlled evaluation of the effects of hyperbaric oxygen therapy on the behavior of 16 children with autism spectrum disorders

Hyperbaric oxygen therapy (HBOT) has been used to treat individuals with autism. However, few studies of its effectiveness have been completed. The current study examined the effects of 40 HBOT sessions at 24% oxygen at 1.3 ATA on 11 topographies of directly observed behavior. Five replications of multiple baselines were completed across a total of 16 participants with autism spectrum disorders. No consistent effects were observed across any group or within any individual participant, demonstrating that HBOT was not an effective treatment for the participants in this study. This study represents the first relatively large-scale controlled study evaluating the effects of HBOT at the level of the individual participant, on a wide array of behaviors.

Autoimmune and gastrointestinal dysfunctions: does a subset of children with autism reveal a broader connection?

A large number of autoimmune disorders have a gastrointestinal (GI) dysfunction component that may interplay with genetic, hormonal, environmental and/or stress factors. This narrarive review investigates possible links between autism, immune system abnormalities and GI symptoms in a subgroup of children with autism. A literature search on Medline (1950 to September 2010) was conducted to identify relevant articles by using the keywords 'autism and gastrointestinal' (71 publications) and 'autism and immune' (237 publications), cross-referencing and general searching to evaluate the available literature on the immunological and GI aspects of autism. Sufficient evidence exists to support that a subgroup of children with autism may suffer from concomitant immune-related GI symptoms.

Pathways underlying the gut-to-brain connection in autism spectrum disorders as future targets for disease management

Autism spectrum disorders (ASDs) are pervasive neurodevelopmental disorders, characterized by impairments in social interaction and communication and the presence of limited, repetitive and stereotyped interests and behavior. Bowel symptoms are frequently reported in children with ASD and a potential role for gastrointestinal disturbances in ASD has been suggested. This review focuses on the importance of (allergic) gastrointestinal problems in ASD. We provide an overview of the possible gut-to-brain pathways and discuss opportunities for pharmaceutical and/or nutritional approaches for therapy.

Immunization and children at risk for autism

Possible connections between immunization and developmental disorders, most notably autistic disorders, have been the subject of a great deal of debate and have caused much concern for parents who want to make the safest choices for their children. Anxiety has risen steadily since the mid-1990s, when a medical investigative team led by A Wakefield postulated that the measles-mumps-rubella (MMR) vaccine may be a causative factor in the development of autism spectrum disorder. Since this initial publication, immunization remains controversial for some parents and the uptake of the MMR vaccine has fallen in some countries, despite much discussion regarding the safety of MMR, a lack of evidence for an association between MMR and autism, and the risks of insufficient protection against wild measles virus infection. The Canadian uptake of MMR in 1998 was 95%, but data do not exist to document any change in Canada since that time. Many clinicians are concerned that the uptake in younger siblings of children with autism is considerably lower.Further anxiety for parents has been caused by the suggested association between developmental disorders and mercury toxicity due to thimerosal, which is used as a preservative in some vaccines. Many Canadian parents, while continuing to seek chelation therapy in response to this suggestion, are not aware that, in Canada, thimerosal has never been added to MMR, and has not been present in diphtheria-pertussis-tetanus-poliomyelitis or pentavalent vaccines since 1992. It is found in only Hepatitis B vaccine in some provinces.The present article is intended to be a guide for physicians as they counsel parents.

Eosinophilic esophagitis as a cause of feeding problems in autistic boy. The first reported case

Unrecognized gastrointestinal disorders may contribute to the behavioral problems in non-verbal patients, but they are often overlooked since the clinical symptoms are nonspecific. Eosinophilic esophagitis (EE) is a chronic inflammatory disorder manifesting itself predominantly in reflux-type symptoms that do not respond to standard anti-reflux pharmacotherapy. Here we report the first case of EE in an autistic patient with feeding difficulties caused by exacerbated EE symptoms.

The prevalence of gastrointestinal problems in children across the United States with autism spectrum disorders from families with multiple affected members

OBJECTIVE

: To perform a large registry-based study to determine the relative prevalence of gastrointestinal (GI) problems in children with an autism spectrum disorder (ASD) from families with multiple affected members compared with their unaffected sibling(s).

METHODS

: In-home structured retrospective medical history interviews by parent recall were conducted by a pediatric neurologist. Our analysis sample included information about GI health of 589 subjects with idiopathic, familial ASD and 163 of their unaffected sibling controls registered with Autism Genetic Resource Exchange. Individuals with ASD were subgrouped into 3 autism severity groups (Full Autism, Almost Autism, and Spectrum) based on their Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Scale scores.

RESULTS

: Parents reported significantly more GI problems in children with ASD (249/589; 42%) compared with their unaffected siblings (20/163; 12%) (p < .001). The 2 most common Gl problems in children with ASD were constipation (116/589; 20%) and chronic diarrhea (111/589; 19%). Conditional logistic regression analysis showed that having Full Autism (adjusted odds ratio [AOR] = 14.28, 95% confidence interval [CI]: 6.22-32.77) or Almost Autism (AOR = 5.16, 95% CI 2.02-13.21) was most highly associated with experiencing GI problems. Increased autism symptom severity was associated with higher odds of GI problems (AOR for trend = 2.63, 95% CI: 1.56-4.45).

CONCLUSIONS

: Parents report significantly more GI problems in children with familial ASD, especially those with Full Autism, than in their unaffected children. Increased autism symptom severity is associated with increased odds of having GI problems.

Dysautonomia in autism spectrum disorder: case reports of a family with review of the literature

Case histories of a mother and her two children are reported. The mother was a recovered alcoholic. She and her two children, both of whom had symptoms that are typical of autistic spectrum disorder, had dysautonomia. All had intermittently abnormal erythrocyte transketolase studies indicating abnormal thiamine pyrophosphate homeostasis. Both children had unusual concentrations of urinary arsenic. All had symptomatic improvement with diet restriction and supplementary vitamin therapy but quickly relapsed after ingestion of sugar, milk, or wheat. The stress of a heavy metal burden, superimposed on existing genetic or epigenetic risk factors, may be important in the etiology of autism spectrum disorder when in combination. Dysautonomia has been associated with several diseases, including autism, without a common etiology. It is hypothesized that oxidative stress results in loss of cellular energy and causes retardation of hard wiring of the brain in infancy, affecting limbic system control of the autonomic nervous system.

Theoretical aspects of autism: biomarkers--a review

Autism is dramatically increasing in incidence and is now considered an epidemic. There are no objective means to diagnose the disorder. Diagnosis is made subjectively, based on the perceived behavior of the subject. This review presents an approach toward development of an objective measure of autism. Covering the literature from 1943 to the present in the PubMed and Ovid Medline databases, this review summarizes evidence of hormones, metabolites, amino acids, and other biomarkers present in significantly different quantities in autistic subjects compared to age- and sex-matched controls. These differences can be measured in the gastrointestinal, immunologic, neurologic, and toxicologic systems of the body, with some biomarkers showing ubiquitous application. In addition, there are unifying concepts, i.e., increased vulnerability to oxidative stress, immune glutamatergic dysfunction, and pineal gland malfunction. The variances of the biomarkers from the norm present the opportunity to create biomarker arrays that when properly developed and analyzed could result in an objective diagnosis with a ranking of the severity of autism for each subject. The contribution of each biomarker to the overall diagnosis could be calculated, thus providing a profile pattern unique to the individual. This profile could consequently provide information for therapeutic interventions on an individual basis.

No association between early gastrointestinal problems and autistic-like traits in the general population

AIM

The aim of this study was to determine whether gastrointestinal problems in early childhood relate to autistic-like traits in a general population sample.

METHOD

The parents of 804 children (442 females; 362 males) reported at 1-, 2-, 3-, and 5-year follow-ups whether their child had been taken to a hospital, general practitioner, or health clinic for any of five gastrointestinal symptoms: (1) constipation; (2) diarrhoea; (3) abdominal bloating, discomfort, or irritability; (4) gastro-oesophageal reflux or vomiting; and (5) feeding issues or food selectivity. Parents also reported whether their child had received the measles, mumps, and rubella vaccination. Autistic-like traits were measured when the children had reached early adulthood (mean age 19 y 7 mo; SD 0.63 y) using a self-report questionnaire, the Autism Spectrum Quotient (AQ).

RESULTS

There was no statistically significant difference in AQ scores between those who had (n=133) and those who had not (n=671) experienced early gastrointestinal symptoms. χ(2) analyses revealed that the children with early gastrointestinal problems were no more likely to be represented in the upper quintile of scores on any of the AQ scales. The measles, mumps, and rubella vaccination was unrelated to gastrointestinal symptoms or AQ scores.

INTERPRETATION

Parent-reported gastrointestinal problems in early childhood are unrelated to self-reported autistic-like traits in the general population.

Constipation in children with autism and autistic spectrum disorder

BACKGROUND

Children with autistic spectrum disorders (ASDs) have long been known to suffer from GIT symptoms. We planned to quantify the contribution of this group to our constipation clinic workload, and to discover defining group characteristics.

METHODS

The characteristics of the bowel habit of children with autism ± neuro-developmental psychiatric (NDP) diagnoses were compared with 'normal' children by retrospective chart review. Data were entered into an Excel spreadsheet (Microsoft Office 2007), and compared between groups.

RESULTS

One hundred and eighteen patients presented to the Paediatric Surgical Constipation clinic between April 2003 and May 2008. 90 patients were otherwise normal; 18 patients had NDP; 6 patients had ASD alone and 4 had ASD with other neurodevelopmental features. The median [interquartile range] age at onset in the ASD + NDP and normal groups was 2.5 (1-6) and 14 (4-36) months, respectively (p = 0.03) and the median duration of history in the ASD ± NDP and normal groups was 61 (47-89) and 27 (13-53) months, respectively (p = 0.007).

CONCLUSIONS

Autism spectrum disorders are an order of magnitude more common in the constipation clinic than in the general population. 8.5% of patients who attended our Paediatric Surgical Constipation clinic had autism with or without NDP deficits. Children with autism ± NDP deficits have an earlier onset of symptoms, longer history, and some possess signs similar to those of slow transit constipation. These features may be inborn. A common genetic origin of gut and behavioural abnormalities suggests that specific targeted investigation and treatment for the constipation of ASD may in time be developed.

Intestinal disaccharidase activity in patients with autism: effect of age, gender, and intestinal inflammation

Intestinal disaccharidase activities were measured in 199 individuals with autism to determine the frequency of enzyme deficiency. All patients had duodenal biopsies that were evaluated morphologically and assayed for lactase, sucrase, and maltase activity. Frequency of lactase deficiency was 58% in autistic children ≤ 5 years old and 65% in older patients. As would be expected, patients with autism at age 5 > years demonstrated significant decline in lactase activity (24%, p = .02) in comparison with ≤ 5 years old autistic patients. Boys ≤ 5 years old with autism had 1.7 fold lower lactase activity than girls with autism (p = .02). Only 6% of autistic patients had intestinal inflammation. Lactase deficiency not associated with intestinal inflammation or injury is common in autistic children and may contribute to abdominal discomfort, pain and observed aberrant behavior. Most autistic children with lactose intolerance are not identified by clinical history.

Digestive enzyme supplementation for autism spectrum disorders: a double-blind randomized controlled trial

To examine the effects of a digestive enzyme supplement in improving expressive language, behaviour and other symptoms in children with Autism Spectrum Disorder. Randomized, double-blind placebo-controlled trial using crossover design over 6 months for 43 children, aged 3-8 years. Outcome measurement tools included monthly Global Behaviour Rating Scales, Additional Rating Scales of other symptoms by parents and therapists, and monthly completion of the Rescorla Language Development Survey. Compared with placebo, treatment with enzyme was not associated with clinically significant improvement in behaviour, food variety, gastrointestinal symptoms, sleep quality, engagement with therapist, or the Language Development Survey Vocabulary or Sentence Complexity Scores. A small statistically significant improvement on enzyme therapy was seen for the food variety scores. No clinically significant effect improvement of autism symptoms with enzyme use was shown with this trial, however, possible effects on improvement in food variety warrants further detailed investigation.

A preliminary study on nutritional status and intake in Chinese children with autism

Parents of children with autism often report gastrointestinal problems as well as picky eating and selective eating in their children. The purpose of this study was to evaluate the nutritional status and the nutrient intake in 111 Chinese children with autism, aged between 2 and 9 years. Anthropometric data were expressed as Z scores. A 3-day dietary recall was provided by the parents, and the data were compared with the national Dietary Reference Intakes (DRI) standards for Chinese children. The results showed that only nine of the autistic children (8.1%) were acute or chronically malnourished. From the remaining 102 patients, 67 (60.4%) were eutrophic and 35 (31.5%) had either overweight or obesity. Intakes of both calories and proteins were adequate in the vast majority of these children, but the calories from fat was lower than DRI in the same age group. The average intake of vitamin E and niacin exceeded 100% of DRI, and the intakes of vitamin B1 and B2, magnesium, and iron were between 80% and 90% of DRI range. However, the following nutrients did not meet the DRI requirements at all: vitamins A, B6 and C, folic acid, calcium, and zinc. Although growth was satisfactory in the vast majority of these children with autistic disorder, this study revealed serious deficiencies in the intakes of several vitamins and essential nutrients.

Combined administration of secretin and oxytocin inhibits chronic colitis and associated activation of forebrain neurons

BACKGROUND

The pathogenesis of inflammatory bowel disease is unknown; however, the disorder is aggravated by psychological stress and is itself psychologically stressful. Chronic intestinal inflammation, moreover, has been reported to activate forebrain neurons. We tested the hypotheses that the chronically inflamed bowel signals to the brain through the vagi and that administration of a combination of secretin (S) and oxytocin (OT) inhibits this signaling.

METHODS

Three daily enemas containing 2,4,6-trinitrobenzene sulfonic acid (TNBS), which were given to rats produced chronic colitis and ongoing activation of Fos in brain neurons.

KEY RESULTS

Fos was induced in neurons in the paraventricular nucleus of the hypothalamus, basolateral amygdala, central amygdala, and piriform cortex. Subdiaphragmatic vagotomy failed to inhibit this activation of Fos, suggesting that colitis activates forebrain neurons independently of the vagi. When administered intravenously, but not when given intracerebroventricularly, in doses that were individually ineffective, combined S/OT prevented colitis-associated activation of central neurons. Strikingly, S/OT decreased inflammatory infiltrates into the colon and colonic expression of tumor necrosis factor-alpha and interferon-gamma.

CONCLUSIONS & INFERENCES

These observations suggest that chronic colonic inflammation is ameliorated by the systemic administration of S/OT, which probably explains the parallel ability of systemic S/OT to inhibit the colitis-associated activation of forebrain neurons. It is possible that S and OT, which are endogenous to the colon, might normally combine to restrict the severity of colonic inflammatory responses and that advantage might be taken of this system to develop novel means of treating inflammation-associated intestinal disorders.

A longitudinal study of gastrointestinal diseases in individuals diagnosed with infantile autism as children

BACKGROUND

A number of studies have indicated a link between gastrointestinal (GI) diseases and autism spectrum disorders.

METHOD

The objective of this study was to compare the prevalence and types of GI diseases in a clinical sample of 118 individuals diagnosed as children with infantile autism (IA) with GI diseases in 336 matched controls from the general population, based on data from the nationwide Danish National Hospital Register (DNHR). The average observation time was 30.3 years (SD 0.4) (range 27-30 years), and mean age at the end of the observation period was 42.7 years (SD 7.7) (range between 27 and 57 years of age).

RESULTS

Of the 118 individuals with IA, 97 (82.2%) had been in contact with a medical hospital (inpatient hospitalization or outpatient visits) during the observation period, compared with 312/336 (92.9%) in the control group (P= 0.001). A similar proportion of members from the case and comparison group had a diagnosis of any GI disease in the DNHR: 30.5% against 30.7%, but the nature of their diseases may be somewhat different. Only diseases of oral cavity were significantly associated with IA: 20.3% against 1.2%, P < 0.0001. Otherwise, specific GI diseases occurred with low frequency in both groups.

CONCLUSION

Overall, no evidence was found that patients with IA were more likely than control persons without IA to have defined GI diseases during the 30.3-year observation period.

Altered brain phospholipid and acylcarnitine profiles in propionic acid infused rodents: further development of a potential model of autism spectrum disorders

Recent studies have demonstrated intraventricular infusions of propionic acid (PPA) a dietary and enteric short-chain fatty acid can produce brain and behavioral changes similar to those observed in autism spectrum disorder (ASD). The effects of PPA were further evaluated to determine if there are any alterations in brain lipids associated with the ASD-like behavioral changes observed following intermittent intraventricular infusions of PPA, the related enteric metabolite butyric acid (BUT) or phosphate-buffered saline vehicle. Both PPA and BUT produced significant increases (p < 0.001) in locomotor activity (total distance travelled and stereotypy). PPA and to a lesser extent BUT infusions decreased the levels of total monounsaturates, total omega6 fatty acids, total phosphatidylethanolamine plasmalogens, the ratio of omega6 : omega3 and elevated the levels of total saturates in separated phospholipid species. In addition, total acylcarnitines, total longchain (C12-C24) acylcarnitines, total short-chain (C2 to C9) acylcarnitines, and the ratio of bound to free carnitine were increased following infusions with PPA and BUT. These results provide evidence of a relationship between changes in brain lipid profiles and the occurrence of ASD-like behaviors using the autism rodent model. We propose that altered brain fatty acid metabolism may contribute to ASD.

Investigation of post-transcriptional gene regulatory networks associated with autism spectrum disorders by microRNA expression profiling of lymphoblastoid cell lines

Background

Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by abnormalities in reciprocal social interactions and language development and/or usage, and by restricted interests and repetitive behaviors. Differential gene expression of neurologically relevant genes in lymphoblastoid cell lines from monozygotic twins discordant in diagnosis or severity of autism suggested that epigenetic factors such as DNA methylation or microRNAs (miRNAs) may be involved in ASD.

Methods

Global miRNA expression profiling using lymphoblasts derived from these autistic twins and unaffected sibling controls was therefore performed using high-throughput miRNA microarray analysis. Selected differentially expressed miRNAs were confirmed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis, and the putative target genes of two of the confirmed miRNA were validated by knockdown and overexpression of the respective miRNAs.

Results

Differentially expressed miRNAs were found to target genes highly involved in neurological functions and disorders in addition to genes involved in gastrointestinal diseases, circadian rhythm signaling, as well as steroid hormone metabolism and receptor signaling. Novel network analyses of the putative target genes that were inversely expressed relative to the relevant miRNA in these same samples further revealed an association with ASD and other co-morbid disorders, including muscle and gastrointestinal diseases, as well as with biological functions implicated in ASD, such as memory and synaptic plasticity. Putative gene targets (ID3 and PLK2) of two RT-PCR-confirmed brain-specific miRNAs (hsa-miR-29b and hsa-miR-219-5p) were validated by miRNA overexpression or knockdown assays, respectively. Comparisons of these mRNA and miRNA expression levels between discordant twins and between case-control sib pairs show an inverse relationship, further suggesting that ID3 and PLK2 are in vivo targets of the respective miRNA. Interestingly, the up-regulation of miR-23a and down-regulation of miR-106b in this study reflected miRNA changes previously reported in post-mortem autistic cerebellum by Abu-Elneel et al. in 2008. This finding validates these differentially expressed miRNAs in neurological tissue from a different cohort as well as supports the use of the lymphoblasts as a surrogate to study miRNA expression in ASD.

Conclusions

Findings from this study strongly suggest that dysregulation of miRNA expression contributes to the observed alterations in gene expression and, in turn, may lead to the pathophysiological conditions underlying autism.

Is urinary indolyl-3-acryloylglycine a biomarker for autism with gastrointestinal symptoms?

An autism spectrum disorder (ASD) diagnosis is based on clinical behaviours as there are no validated biological diagnostic tools. Indolyl-3-acryloylglycine (IAG) is a chemical produced by gut microflora and there are conflicting reports as to whether urinary levels are elevated in children with ASD compared with controls. Urinary IAG levels in morning urine samples were statistically significantly higher in children with ASD whose caregivers reported the presence of chronic gastrointestinal (GI) disturbance than children with ASD without chronic GI disturbance. Urinary IAG, however, was not statistically significantly higher in children with ASD, compared with siblings or unrelated controls without ASD.

Nutritional Intake and Therapies in Autism

Autism is one of the fastest growing developmental disabilities in the United States. With every 1 in 100 children diagnosed with autism, this condition is more common than pediatric cancer, diabetes, and AIDS combined. Core deficits of autism limit functioning in social interaction, communication, and daily activity participation. Individuals with autism typically require significant levels of supervised care, special education resources, and health service throughout life. The nutritional status of children with autism is receiving increasing attention in the field. Nutrient deficiencies have been proposed as a causative factor in the manifestation of the disorder. Further, characteristic autism behaviors and autism-specific interventions may increase the risk of suboptimal nutrition. Part 1 of this paper provides a review as to what is currently known regarding the nutrient intake and/or nutritional status of children with autism, and the myriad factors—both medical/nutritional and behavioral/ contextual—likely to impact dietary intake and nutritional status. Part 2 explores nutrition interventions (special diets and dietary supplements or “biomedical” interventions) in terms of safety and efficacy, as well as behavioral interventions used in autism spectrum disorder.