The Role of Vitamins in Autism Spectrum Disorder: What Do We Know?

Exploring Dietary Interventions in Autism Spectrum Disorder

Autism spectrum disorder (ASD) involves social communication difficulties and repetitive behaviors, and it has a growing prevalence worldwide. Symptoms include cognitive impairments, gastrointestinal (GI) issues, feeding difficulties, and psychological problems. A significant concern in ASD is food selectivity, leading to nutrient deficiencies. Common GI issues in ASD, such as constipation and irritable bowel syndrome, stem from abnormal gut flora and immune system dysregulation. Sensory sensitivities and behavioral challenges exacerbate these problems, correlating with neurological symptom severity. Children with ASD also exhibit higher oxidative stress due to low antioxidant levels like glutathione. Therapeutic diets, including ketogenic, high-antioxidant, gluten-free and casein-free, and probiotic-rich diets, show potential in managing ASD symptoms like behavior, communication, GI issues, and oxidative stress, though the evidence is limited. Various studies have focused on different populations, but there is increasing concern about the impact among children. This review aims to highlight the food preferences of the ASD population, analyze the effect of the physicochemical and nutritional properties of foods on the selectivity in its consumption, GI problems, and antioxidant deficiencies in individuals with ASD, and evaluate the effectiveness of therapeutic diets, including diets rich in antioxidants, gluten-free and casein-free, ketogenic and essential fatty acids, and probiotic-rich diets in managing these challenges.

Gluten-Free, Casein-Free Diet for Children with Autism Spectrum Disorder: A Case-Controlled Study

Background and Objectives

Numerous therapeutic and dietary interventions have been examined in the last thirty years for pediatric patients diagnosed with autism spectrum disorder (ASD). Our interventional study aimed to assess the effectiveness of the gluten-free, casein-free (GFCF) diet in a cohort of Egyptian children with ASD.

Materials and Methods

The present clinical trial was conducted as a prospective 12-month, open-label, case-controlled interventional study. Thirty-six ASD children who were newly diagnosed and had not taken any prior psychiatric or rehabilitation therapy were included in this study. The patients were randomly assigned into two groups: group A, which received the GFCF diet, and group B, which served as the control group and was not restricted to food containing gluten and casein for 12 months. All patients were followed up for 1 year.

Results

Following the implementation of the GFCF diet in group A, significant improvements in CARS scores were observed compared to group B after 6-month and 1-year follow-up periods.

Conclusions

The introduction of the GFCF diet could be helpful and promising for autistic children. Conclusive evidence regarding the effectiveness of the GFCF diet remains a subject of controversy. Nonetheless, our study contributes some evidence supporting its potential benefits for children with ASD. It is recommended that future research on the GFCF diet employ a more sophisticated research design, incorporating a consistent baseline measure that can effectively assess the therapeutic effects of these interventions for individuals with ASD.

Advances in the Treatment of Autism Spectrum Disorder: Current and Promising Strategies

Autism spectrum disorder (ASD) is an umbrella term for developmental disorders characterized by social and communication impairments, language difficulties, restricted interests, and repetitive behaviors. Current management approaches for ASD aim to resolve its clinical manifestations based on the type and severity of the disability. Although some medications like risperidone show potential in regulating ASD-associated symptoms, a comprehensive treatment strategy for ASD is yet to be discovered. To date, identifying appropriate therapeutic targets and treatment strategies remains challenging due to the complex pathogenesis associated with ASD. Therefore, a comprehensive approach must be tailored to target the numerous pathogenetic pathways of ASD. From currently viable and basic treatment strategies, this review explores the entire field of advancements in ASD management up to cutting-edge modern scientific research. A novel systematic and personalized treatment approach is suggested, combining the available medications and targeting each symptom accordingly. Herein, summarize and categorize the most appropriate ways of modern ASD management into three distinct categories: current, promising, and prospective strategies.

The importance of comprehensive support based on the three pillars of exercise, nutrition, and sleep for improving core symptoms of autism spectrum disorders

Autism spectrum disorder (ASD) is classified as a neurodevelopmental disorder. The Diagnostic and Statistical Manual of Mental Disorders (DSM)-V, which first described ASD, lists persistent deficits in social communication and interrelationships, as well as limited and recurrent modes of behavior, interests, and activities as diagnostic items. Until recently, understanding the pathophysiology of ASD has been mostly from a neurophysiological perspective, and interventions have been mostly behavioral and psychological. In recent years, however, it has become clear that ASD also affects many bodily systems, including the immune system, the sensorimotor system, and the gut-brain axis, and that these factors simultaneously influence it. In light of this background, a new "connectivome theory" has been proposed as a hypothesis for understanding ASD. "Exercise," "nutrition," and "sleep," which are discussed in this mini-review, have a particularly strong relationship with the immune, musculoskeletal, and gut systems among the pathologies mentioned in the "connectivome theory," furthermore, many reports suggest improvements in stereo-responsive behavior and social and communication skills, which are the core symptoms of ASD. In addition, these interventions are characterized by being less subject to location and cost limitations and excel in the continuity of therapeutic intervention, and the three interventions may have a reciprocal positive impact and may function as three pillars to support ASD.

Neuroinflammation and Oxidative Stress in the Pathogenesis of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder (NDD) characterized by impairments in social communication, repetitive behaviors, restricted interests, and hyperesthesia/hypesthesia caused by genetic and/or environmental factors. In recent years, inflammation and oxidative stress have been implicated in the pathogenesis of ASD. In this review, we discuss the inflammation and oxidative stress in the pathophysiology of ASD, particularly focusing on maternal immune activation (MIA). MIA is a one of the common environmental risk factors for the onset of ASD during pregnancy. It induces an immune reaction in the pregnant mother’s body, resulting in further inflammation and oxidative stress in the placenta and fetal brain. These negative factors cause neurodevelopmental impairments in the developing fetal brain and subsequently cause behavioral symptoms in the offspring. In addition, we also discuss the effects of anti-inflammatory drugs and antioxidants in basic studies on animals and clinical studies of ASD. Our review provides the latest findings and new insights into the involvements of inflammation and oxidative stress in the pathogenesis of ASD.

Current evidence for adjunct pyridoxine (vitamin B6) for the treatment of behavioral adverse effects associated with levetiracetam: A systematic review

BACKGROUND

Levetiracetam (LVT), while an effective treatment for multiple seizure types, is associated with a high incidence of neuropsychiatric adverse events (NPAEs). In predominantly retrospective studies, supplementation with pyridoxine/vitamin B₆ (PN) was associated with improvement in NPAEs in some people. A previous review highlighted a lack of double-blind, controlled trials of PN for the treatment of NPAEs in individuals treated with LVT. The current paper updates the findings from the previous review to include evidence from studies published since June 2019.

METHODS

An updated systematic review of the published literature was performed in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Embase, the Cochrane Library, and Google Scholar were searched to identify studies published between June 2019 and 2nd November 2022 in which supplementary PN was initiated for the treatment of LVT-associated NPAEs. All study types were eligible. The risk of bias in randomized trials was assessed using the Cochrane risk-of-bias tool.

RESULTS

Seven additional studies were identified: two double-blind, randomized controlled trials (RCTs), four retrospective studies, and one retrospective case series. One RCT reported significant improvements from baseline in behavioral adverse events (BAEs) in both the intervention (PN) group and the low-dose control group (both p < 0.05), with a significantly greater improvement in the intervention group (p < 0.001). In the second RCT, differences in BAE severity between PN and placebo groups at the endpoint were not statistically significant. In one retrospective study, subjective irritability was reported to have improved from baseline in 9/20 individuals (45%) treated with supplementary PN. Data for systematic assessments (PHQ-9 and GAD-7) were available for 10 individuals. Assessment by PHQ-9 showed that six individuals improved, two worsened and two had no change. Based on the GAD-7, three people improved, two worsened and five had no change. In the second retrospective study, 18/41 individuals (44%) who commenced PN following the emergence of BAEs showed "significant" improvement. In a separate group of individuals with pre-existing behavioral problems in whom PN treatment was initiated at the same time as commencing LVT, 3/18 (16.7%) developed BAEs. This compared with 79/458 people (17.2%) who were initially treated only with LVT. The third retrospective study compared treatment-related irritability in individuals who had been treated with both LVT and perampanel, either sequentially or concomitantly. Two people who developed irritability while receiving LVT monotherapy were able to continue treatment with the addition of PN. The fourth study reported a significantly lower LVT discontinuation rate in individuals taking PN and a higher rate of improved behavior in those who were able to continue LVT. The case series reported improvements in behavioral symptoms in six people within two to three weeks of commencing supplementary PN.

CONCLUSION

Data published within the last three years add to earlier evidence suggesting that PN might be effective in the treatment of NPAEs associated with LVT. However, the quality of evidence remains poor and only a few prospective trials have been published. Data from placebo-controlled trials are still largely lacking. Currently, there is insufficient evidence to justify any firm recommendation for PN supplementation to treat NPAEs associated with LVT. Further well-designed, prospective trials are warranted.

Vitamin D3-Loaded Nanoemulsions as a Potential Drug Delivery System for Autistic Children: Formulation Development, Safety, and Pharmacokinetic Studies

The aim of the current study is the development of a vitamin D₃ (VD3)-loaded nanoemulsion (NE) formulation to improve VD3 oral bioavailability for management of vitamin D inadequacy in autistic children. Eight NE formulations were prepared by high-speed homogenization followed by ultrasonication. Four vegetable oils were employed along with two concentrations of Span 20 as the emulsifier. Glycerol, fructose, and mango flavor were included as viscosity modifier, sweetening, and flavoring agents, respectively. The prepared VD3-loaded NE formulations exhibited high drug content (> 98%), droplet size (DS) ranging from 61.15 to 129.8 nm with narrow size distribution, zeta potential values between - 9.83 and - 19.22 mV, and acceptable pH values (4.59-5.89). Storage stability showed that NE formulations underwent coalescence and phase separation during 6 months at room temperature, whereas at refrigerated conditions, formulations showed slight creaming. The optimum formulation (VD3-NE6) revealed a non-significant DS growth at refrigerated conditions and spherical morphology under transmission electron microscopy. VD3-NE6 did not produce any toxic effects to rats treated orally for 3 months, where normal blood picture and kidney and liver functions were observed compared to control rats. Also, serum calcium, oxidative stress, and apoptosis biomarkers remained within normal levels, indicating the safety of the optimum formulation. Furthermore, evaluation of VD3-NE6 oral bioavailability depicted a significant increase in AUC_0-72 and C_max with decreased T_max compared to plain VD3. The optimum formulation demonstrated improved stability, safety, and oral bioavailability indicating the potential for successful management of vitamin D deficiency in autistic children.

Nutrient intake and adequacy in children with autism spectrum disorder: EPINED epidemiological study

LAY ABSTRACT

Children with autism spectrum disorder (ASD) have a fivefold elevated risk of developing eating problems, which predisposes them to nutritional deficiencies. This study assesses nutritional intake and adequacy in children with ASD, subdiagnostic autistic symptoms and typically developing (TD) children. Preschool children with ASD and subdiagnostic symptoms had slightly lower intake of monounsaturated fatty acids (MUFA), vitamin D and vitamin B12. Primary school children with ASD and subdiagnostic symptoms had slightly higher intake of protein, cholesterol, thiamine and niacin, and a higher percentage of obesity than children with TD. All children had a high intake in sugars, fats and saturated fatty acids; a very highly inadequate intake of vitamins (vitamins D and E), fibre, b-carotene, calcium and magnesium; and a moderately inadequate intake of vitamin C, folate and iron. However, although all children need nutrition advice, children with ASD and subdiagnostic autistic symptoms had a poorer quality diet than those with TD.

Gene-environment interactions in Alzheimer disease: the emerging role of epigenetics

With the exception of a few monogenic forms, Alzheimer disease (AD) has a complex aetiology that is likely to involve multiple susceptibility genes and environmental factors. The role of environmental factors is difficult to determine and, until a few years ago, the molecular mechanisms underlying gene-environment (G × E) interactions in AD were largely unknown. Here, we review evidence that has emerged over the past two decades to explain how environmental factors, such as diet, lifestyle, alcohol, smoking and pollutants, might interact with the human genome. In particular, we discuss how various environmental AD risk factors can induce epigenetic modifications of key AD-related genes and pathways and consider how epigenetic mechanisms could contribute to the effects of oxidative stress on AD onset. Studies on early-life exposures are helping to uncover critical time windows of sensitivity to epigenetic influences from environmental factors, thereby laying the foundations for future primary preventative approaches. We conclude that epigenetic modifications need to be considered when assessing G × E interactions in AD.

Ketogenic Diet: A Dietary Intervention via Gut Microbiome Modulation for the Treatment of Neurological and Nutritional Disorders (a Narrative Review)

The ketogenic diet (KD) has been important in treating epilepsy since the 1920s. The benefits of KD further expanded to other neurological diseases, including Alzheimer’s diseases, autism spectrum disorder, and nutritional disorder (obesity). Although the therapeutic efficacy of KD has been generally accepted, there is limited knowledge about its underlying mechanism of action, particularly its effect on our gut microbiome. Gut dysbiosis has been proposed to be involved in those diseases, and KD can promote gut microbiota remodeling that may assist in recovery. This review explores the therapeutic applications of KD, the roles of the gut microbiome in neurological diseases and obesity, as well as the effect of KD on the gut microbiome. The present information suggests that KD has significant roles in altering the gut microbiome to improve disease symptoms, mainly by incrementing Bacteroidetes to Firmicutes (B/F) ratio and reducing Proteobacteria in certain cases. However, current gaps call for continued research to understand better the gut microbiota profile altered by KD.

Effect of Supplementation on Levels of Homovanilic and Vanillylmandelic Acids in Children with Autism Spectrum Disorders

Autism Spectrum Disorders (ASD) are characterized by numerous comorbidities, including various metabolic and nutritional abnormalities. In many children with ASD, problems with proper nutrition can often lead to inadequate nutrient intake and some disturbances in metabolic profiles, which subsequently correlate with impaired neurobehavioural function. The purpose of this study was to investigate and compare the relationship between supplementation, levels of homovanillic acid (HVA) and vanillylmandelic acid (VMA) and the behaviour of children with ASD using quantitative urinary acid determination and questionnaires provided by parents/caregivers. The study was carried out on 129 children between 3 and 18 years of age. HVA and VMA were extracted and derivatized from urinary samples and simultaneously analyzed by gas chromatography-mass spectrometry (GC-MS). In addition, parents/caregivers of children with ASD were asked to complete questionnaires containing information about their diet and intake/non-intake of supplements. The application of the Mann–Whitney U test showed a statistically significant difference between the level of HVA and vitamin B supplementation (p = 1.64 × 10⁻²) and also omega-6 fatty acids supplementation and the levels of HVA (p = 1.50 × 10⁻³) and VMA (p = 2.50 × 10⁻³). In some children, a reduction in the severity of autistic symptoms (better response to own name or better reaction to change) was also observed. These results suggest that supplementation affects the levels of HVA and VMA and might also affect the children’s behaviour. Further research on these metabolites and the effects of supplementation on their levels, as well as the effects on the behaviour and physical symptoms among children with ASD is needed.

Serum Galanin in Children with Autism Spectrum Disorder

Recent studies have attempted to measure several biomarkers to understand the complex interactions of the anatomic systems that may be involved in autism spectrum disorder (ASD). In CNS, galanin takes part in a variety of pathological and physiological processes. Prior research has indicated it is involved in several neuropsychiatric disorders and has a role in inhibiting the neuronal firing and release of serotonin, norepinephrine, and acetylcholine. To date, serum galanin levels have not been investigated in the context of ASD. This study aimed, therefore, to compare the serum galanin levels of children with ASD and healthy controls and to reveal any association between galanin level and the severity of ASD, as well as other psychological and demographic parameters. Serum galanin levels were measured by radioimmunoassay in 116 children with ASD and 98 healthy children. We observed significantly increased serum concentrations of galanin in children with ASD relative to healthy children. Moreover, children with severe ASD had significantly higher galanin levels than those with less severe disease. We also confirmed significant positive correlations between galanin and psychiatric parameters in children with ASD. For the first time, we suggest a possible correlation between serum galanin and the degree of ASD severity. Increased galanin levels may play a role in the pathogenesis of ASD.

Research Progress in Vitamin A and Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a highly heterogeneous neurodevelopmental disorder. Over the past few decades, many studies have investigated the effects of VA supplementation in ASD patients and the relationship between vitamin A (VA) levels and ASD. VA is an essential micronutrient that plays an important role in various systems and biological processes in the form of retinoic acid (RA). Recent studies have shown that serum VA concentration is negatively correlated with the severity of ASD. The lack of VA during pregnancy or early fetal development can affect brain development and lead to long-term or even permanent impairment in the learning process, memory formation, and cognitive function. In addition, VA deficiency has been reported to have a major impact on the gastrointestinal function of children with ASD, while VA supplementation has been shown to improve the symptoms of ASD to a certain extent. This paper provides a comprehensive review of the relationship between VA and ASD.

Paving Plant-Food-Derived Bioactives as Effective Therapeutic Agents in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, where social and communication deficits and repetitive behaviors are present. Plant-derived bioactives have shown promising results in the treatment of autism. In this sense, this review is aimed at providing a careful view on the use of plant-derived bioactive molecules for the treatment of autism. Among the plethora of bioactives, curcumin, luteolin, and resveratrol have revealed excellent neuroprotective effects and can be effectively used in the treatment of neuropsychological disorders. However, the number of clinical trials is limited, and none of them have been approved for the treatment of autism or autism-related disorder. Further clinical studies are needed to effectively assess the real potential of such bioactive molecules.

Alterations in Gut Vitamin and Amino Acid Metabolism are Associated with Symptoms and Neurodevelopment in Children with Autism Spectrum Disorder

Metabolic disturbance may be implicated in the pathogenesis of autism. This study aimed to investigate the gut metabolomic profiles of autistic children and to analyze potential interaction between gut metabolites with autistic symptoms and neurodevelopment levels. We involved 120 autistic and 60 neurotypical children. Autistic symptoms and neurodevelopment levels were assessed. Fecal samples were analyzed using untargeted liquid chromatography-tandem mass spectrometry methods. Our results showed the metabolic disturbances of autistic children involved in multiple vitamin and amino acid metabolism pathways, with the strongest enrichment identified for tryptophan metabolism, retinol metabolism, cysteine-methionine metabolism, and vitamin digestion and absorption. Differential gut metabolites were correlated to autistic symptoms and neurodevelopment levels. Our findings improved the understanding of the perturbations of metabolome networks in autism.

Vitamin D levels in children and adolescents with autism

OBJECTIVE

This study aimed to investigate the relationship between autism spectrum disorder (ASD) and vitamin D levels in children and adolescents.

METHODS

We measured serum 25-hydroxyvitamin D (25-OHD) levels in 1529 patients with ASD aged 3 to 18 years, without any additional chronic diseases. Levels of 25-OHD were compared according to sex, age (<11 or ≥11 years), and birth season. Additionally, laboratory parameters (calcium, phosphorus, alkaline phosphatase, and 25-OHD) of 100 selected patients with ASD were compared with those of the healthy control group.

RESULTS

Vitamin D deficiency or insufficiency was found in approximately 95% of all patients. Levels of 25-OHD in adolescent patients with ASD aged 11 to 18 years were significantly lower than those in patients aged younger than 11 years. In the 100 selected patients with ASD, mean serum 25-OHD levels were significantly lower and alkaline phosphatase levels were higher compared with those in healthy children.

CONCLUSION

Our study suggests a relationship between vitamin D and ASD in children. Monitoring vitamin D levels is crucial in autistic children, especially adolescents, to take protective measures and treat this condition early.

What is autism?

The term "Autism spectrum disorder" (ASD), in vogue at present, has evolved after continual substantial developments taking place over more than a century. ASD is a heterogeneous, multi-factorial, developmental disability in which an unusual pattern of development takes place during infant and toddler years. As per DSM-5, Autism spectrum disorder is a combined phrase for a family of complex developmental disabilities inclusive of "Autistic Disorder, Pervasive Developmental Disorder not Otherwise Specified (PDD-NOS), and Asperger's Disorder". "ASD is characterized not only by persistent impairments in reciprocal social communication and social interactions, but is also manifested by restricted, repetitive patterns of behavior, interests, or activities". The classical clinical signs that exist in two major domains, viz. the 'social domain' and the 'behavioral domain' for the precise diagnosis of ASD have been tabulated and major differences between DSM-5 and DSM-4 are depicted with the help of a figure in this basic review article. A sharp rise in the incidence of ASD cases has been observed worldwide owing to various risk factors such as genetic predisposition coupled with adverse environmental conditions, gynecological interventions, etc. Two official manuals viz. the "Diagnostic and Statistical Manual of Mental Disorders" (DSM) (published by the American Psychiatric Association), and the "International Classification of Diseases" (ICD) (published by the World Health Organization) is being regularly updated to facilitate diagnosis of ASD. ICD-11 guidelines being prospectively implemented with effect from January 2022 have attracted global attention.

Polymorphism of interleukin-1β and interleukin-1 receptor antagonist genes in children with autism spectrum disorders

In this study, we first investigated interleukin-1 beta (IL-1β) and IL-1 receptor antagonist (IL-1RA) levels in a cohort of Egyptian children with autism spectrum disorder (ASD) and in healthy controls. Second, we examined the single-nucleotide polymorphisms (SNPs) at positions -31 and - 511 of the IL-1β gene promoter and IL1RA and assessed the association between IL1B and IL1RA polymorphisms with ASD. We examined IL1β promoter polymorphism at -511 (IL-1β-511) and - 31 (IL-1β-31) and IL1RA gene polymorphism in 80 children with ASD and 60 healthy children. The children with ASD had significantly higher levels of IL-1β and IL-1RA than the controls. The children with ASD also had significantly higher frequencies of homozygous (CC) and heterozygous (TC) genotype variants of IL-1β-511, and IL-1RA than the controls. Moreover, the frequency of the IL-1β-511 allele (C) was higher in the ASD group than in the controls (p = .001). The homozygous and heterozygous variants of IL-1RA allele II were also significantly higher in the ASD group than in the control group. There was no significant association between the IL-1β-31 genotype and autism classes. However, there were significant differences in the distribution of the IL-1RA heterogeneous genotype and allele II among children with severe autism. The inflammatory role of cytokines has been implicated in a variety of neuropsychiatric pathologies, including autism. Our data show alterations in the IL-1β system, with abnormally increased serum levels of IL-1β and IL-1RA in the children with ASD. Further, polymorphisms in the IL-1β-511 and IL-1RA genotype variants correlated positively with autism severity and behavioral abnormalities. IL-1β-511 and IL-1RA gene polymorphisms could impact ASD risk and may be used as potential biomarkers of ASD. Variations in the IL-1β and IL-1RA systems may have a role in the pathophysiology of ASD.

Emerging risk of environmental factors: insight mechanisms of Alzheimer's diseases

Neurodegenerative disorders are typically sporadic in nature in addition to usually influenced through an extensive range of environmental factors, lifestyle, and genetic elements. Latest observations have hypothesized that exposure of environmental factors may increase the prospective risk of Alzheimer's diseases (AD). However, the role of environmental factors as a possible dangerous issue has extended importance concerned in AD pathology, although actual etiology of the disorder is still not yet clear. Thus, the aim of this review is to highlight the possible correlation between environmental factors and AD, based on the present literature view. Environmental risk factors might play an important role in decelerating or accelerating AD progression. Among well-known environmental risk factors, prolonged exposure to several heavy metals, for example, aluminum, arsenic, cadmium, lead, and mercury; particulate air, and some pesticides as well as metal-containing nanoparticles have been participated to cause AD. These heavy metals have the capacity to enhance amyloid β (Aβ) peptide along with tau phosphorylation, initiating amyloid/senile plaques, as well as neurofibrillary tangle formation; therefore, neuronal cell death has been observed. Furthermore, particulate air, pesticides, and heavy metal exposure have been recommended to lead AD susceptibility and phenotypic diversity though epigenetic mechanisms. Therefore, this review deliberates recent findings detailing the mechanisms for a better understanding the relationship between AD and environmental risk factors along with their mechanisms of action on the brain functions.

Vitamin C Attenuates Oxidative Stress and Behavioral Abnormalities Triggered by Fipronil and Pyriproxyfen Insecticide Chronic Exposure on Zebrafish Juvenile

Chronic exposure to synthetic insecticides in the early life of a child can lead to a series of disorders. Several causes as parental age, maternal smoking, birth complications, and exposure to toxins such as insecticides on childhood can lead to Autism spectrum disorder (ASD) occurrence. The aim of this study was to evaluate the potential protective role of vitamin C (Vit. C) from children's supplements after 14 days chronic exposure to insecticide mixture fipronil (Fip) + pyriproxyfen (Pyr) on juvenile zebrafish for swimming performances, social behavior and oxidative stress associated with ASD model. Juvenile (14-17 mm) wild-type AB zebrafish (Danio rerio) (45 days) were exposed to relevant concentrations: vit. C (25 µg L-1), Fip (600 µg L-1/1.372 μM) + Pyr (600 µg L-1/1.89 μM), and [Fip (600 µg L-1/1.372 μM) + Pyr (600 µg L-1 /1.89 μM)] + vit. C (25 µg L-1). Our results showed that insecticides can disturb the social behavior of zebrafish during 14 days of the administration, decreased the swimming performances, and elevated the oxidative stress biomarkers of SOD (superoxide dismutase), GPx (glutathione peroxidase), and MDA (malondialdehyde). The vitamin C supplement significantly attenuated the neurotoxicity of insecticide mixture and oxidative stress. This study provides possible in vivo evidence to show that vitamin C supplements could attenuate oxidative stress and brain damage of fipronil and pyriproxyfen insecticide chronic exposure on zebrafish juvenile.

Relationship between Vitamin Deficiencies and Co-Occurring Symptoms in Autism Spectrum Disorder

Recently, connections have been made between feeding and eating problems and autism spectrum disorder (ASD) and between autism pathophysiology and diet issues. These could explain some of the mechanisms which have not yet been discovered or are not sufficiently characterized. Moreover, there is an increased awareness for micronutrients in ASD due to the presence of gastrointestinal (GI) problems that can be related to feeding issues. For example, levels of vitamins B₁, B₆, B₁₂, A and D are often reported to be low in ASD children. Thus, in the present mini review we focused on describing the impact of some vitamins deficiencies and their relevance in ASD patients.

Oxidative Stress and Immune System Dysfunction in Autism Spectrum Disorders

Autism Spectrum Disorders (ASDs) represent a group of neurodevelopmental disorders associated with social and behavioral impairments. Although dysfunctions in several signaling pathways have been associated with ASDs, very few molecules have been identified as potentially effective drug targets in the clinic. Classically, research in the ASD field has focused on the characterization of pathways involved in neural development and synaptic plasticity, which support the pathogenesis of this group of diseases. More recently, immune system dysfunctions have been observed in ASD. In addition, high levels of reactive oxygen species (ROS), which cause oxidative stress, are present in ASD patients. In this review, we will describe the major alterations in the expression of genes coding for enzymes involved in the ROS scavenging system, in both ASD patients and ASD mouse models. In addition, we will discuss, in the context of the most recent literature, the possibility that oxidative stress, inflammation and immune system dysfunction may be connected to, and altogether support, the pathogenesis and/or severity of ASD. Finally, we will discuss the possibility of novel treatments aimed at counteracting the interplay between ROS and inflammation in people with ASD.

Hair trace element concentrations in autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD)

BACKGROUND

The existing data demonstrate that alteration of trace element and mineral status in children with neurodevelopmental disorders including ASD and ADHD. However, comparative analysis of the specific patterns of trace element and mineral metabolism in children with ASD and ADHD was not performed. Therefore, the primary objective of the present study was to assess hair trace element and mineral levels in boys with ADHD, ASD, as well as ADHD with ASD.

METHODS

Boys with ADHD (n = 52), ASD (n = 53), both ADHD and ASD (n = 52), as well as neurotypical controls (n = 52) were examined. Hair analysis was performed using inductively-coupled plasma mass-spectrometry.

RESULTS

The obtained data demonstrate that hair Co, Mg, Mn, and V levels were significantly reduced in children with ADHD and ASD, and especially in boys with ADHD + ASD. Hair Zn was found to be reduced by 20% (p = 0.009) only in children with ADHD + ASD as compared to healthy controls. Factor analysis demonstrated that ASD was associated with significant alteration of hair Co, Fe, Mg, Mn, and V levels, whereas impaired hair Mg, Mn, and Zn content was also significantly associated with ADHD. In regression models hair Zn and Mg were negatively associated with severity of neurodevelopmental disorders. The revealed similarity of trace element and mineral disturbances in ASD and ADHD may be indicative of certain similar pathogenetic features.

CONCLUSION

The obtained data support the hypothesis that trace elements and minerals, namely Mg, Mn, and Zn, may play a significant role in development of both ADHD and ASD. Improvement of Mg, Mn, and Zn status in children with ASD and ADHD may be considered as a nutritional strategy for improvement of neurodevelopmental disturbances, although clinical trials and experimental studies are highly required to support this hypothesis.

Specialized Diet Therapies: Exploration for Improving Behavior in Autism Spectrum Disorder (ASD)

As a major neurodevelopmental disorder, Autism Spectrum Disorder (ASD) encompasses deficits in communication and repetitive and restricted interests or behaviors in childhood and adolescence. Its etiology may come from either a genetic, epigenetic, neurological, hormonal, or an environmental cause, generating pathways that often altogether play a synergistic role in the development of ASD pathogenesis. Furthermore, the metabolic origin of ASD should be important as well. A balanced diet consisting of the essential and special nutrients, alongside the recommended caloric intake, is highly recommended to promote growth and development that withstand the physiologic and behavioral challenges experienced by ASD children. In this review paper, we evaluated many studies that show a relationship between ASD and diet to develop a better understanding of the specific effects of the overall diet and the individual nutrients required for this population. This review will add a comprehensive update of knowledge in the field and shed light on the possible nutritional deficiencies, metabolic impairments (particularly in the gut microbiome), and malnutrition in individuals with ASD, which should be recognized in order to maintain the improved socio-behavioral habit and physical health.

China Multi-Center Preschool Autism Project (CMPAP): Design and Methodologies to Identify Clinical Symptom Features and Biomarkers of Autism Spectrum Disorders

Background: The etiology of autism spectrum disorder (ASD) has not yet been fully identified, but it seems to be triggered by complex genetic and environmental risk factors. Moreover, the tremendous etiological and clinical differences among individuals with ASD has had a major negative impact on early diagnosis and individualized treatment. Earlier diagnosis of precise clinical subtypes of ASD could lead to individualized treatment and a better prognosis. However, few large-scale epidemiological studies have explored precise clinical subtypes and clinically meaningful biomarkers, especially in China. Methods and Design: The China Multi-center Preschool Autism Project (CMPAP) includes nearly 3,000 children-1,469 individuals with ASD and 1,499 typically-developing (TD) controls-from 13 cities in China. Using a case-control design, each participant was comprehensively characterized in terms of feeding and disease history, maternal history, family history, clinical core symptoms, comorbidities, biochemical markers, genomics, urine/fecal metabonomics, and intestinal flora. In addition, data on environmental risk factors were obtained using interviews and electronic medical records. Conclusion: The study was designed to: (1) investigate age at diagnosis and treatment and family and social support for preschool children with ASD in China, (2) develop a more accurate clinical subtype and intervention system for the ICD-11, and (3) find the specific genes and environmental markers of different subtypes, which will help in the development of early diagnosis and individual intervention programs for preschool children with ASD. This study will provide the basis for improving national health policies for ASD in China.

Gestational B-vitamin supplementation alleviates PM2.5-induced autism-like behavior and hippocampal neurodevelopmental impairment in mice offspring

Gestational exposure to PM_2.5 is a worldwide environmental issue associated with long-lasting behavior abnormalities and neurodevelopmental impairments in the hippocampus of offspring. PM_2.5 may induce hippocampus injury and lead to autism-like behavior such as social communication deficits and stereotyped repetitive behavior in children through neuroinflammation and neurodegeneration. Here, we investigated the preventive effect of B-vitamin on PM_2.5-induced deleterious effects by focusing on anti-inflammation, antioxidant, synaptic remodeling and neurodevelopment. Pregnant mice were randomly divided into three groups including control group (mice subject to PBS only), model group (mice subject to both 30 μL PM_2.5 of 3.456 μg/μL and 10 mL/(kg·d) PBS), and intervention group (mice subject to both 30 μL PM_2.5 of 3.456 μg/μL and 10 mL/(kg·d) B-vitamin supplementation (folic acid, vitamin B6 and vitamin B12 with concentrations at 0.06, 1.14 and 0.02 mg/mL, respectively)). In the current study B-vitamin significantly alleviated neurobehavioral impairment reflected in reduced social communication disorders, stereotyped repetitive behavior, along with learning and spatial memory impairment in PM_2.5-stimulated mice offspring. Next, B-vitamin corrected synaptic loss and reduced mitochondrial damage in hippocampus of mice offspring, demonstrated by normalized synapse quantity, synaptic cleft, postsynaptic density (PSD) thickness and length of synaptic active area. Furthermore, significantly down-regulated expression of pro-inflammatory cytokines including NF-κB, TNF-α and IL-1β, and lipid peroxidation were found. We observed elevated levels of oxidant-related genes (SOD, GSH and GSH-Px). Moreover, decreased cleaved caspase-3 and TUNEL-positive cells suggested inhibited PM_2.5-induced apoptosis by B-vitamin. Furthermore, B-vitamin increased neurogenesis by increasing EdU-positive cells in the subgranular zone (SGZ) of offspring. Collectively, our results suggest that B-vitamin supplementation exerts preventive effect on autism-like behavior and neurodevelopmental impairment in hippocampus of mice offspring gestationally exposed to PM_2.5, to which alleviated mitochondrial damage, increased anti-inflammatory and antioxidant capacity and synaptic efficiency, reduced neuronal apoptosis and improved hippocampal neurogenesis may contribute.

Effects of l-Carnitine in Patients with Autism Spectrum Disorders: Review of Clinical Studies

Carnitine is an amino acid derivative, which plays several important roles in human physiology, in the central nervous system, and for mitochondrial metabolism, in particular. Altered carnitine metabolic routes have been associated with a subgroup of patients with autism spectrum disorders (ASD) and could add to the pathophysiology associated with these disorders. We review the current evidence about the clinical effects of carnitine administration in ASD in both non-syndromic forms and ASD associated with genetic disorders. Two randomized clinical trials and one open-label prospective trial suggest that carnitine administration could be useful for treating symptoms in non-syndromic ASD. The effect of carnitine administration in ASD associated with genetic disorders is not conclusive because of a lack of clinical trials and objectives in ASD evaluation, but beneficial effects have also been reported for other comorbid disorders, such as intellectual disability and muscular strength. Side effects observed with a dose of 200 mg/kg/day consisted of gastro-intestinal symptoms and a strong, heavy skin odor. Doses of about 50–100 mg/kg/day are generally well tolerated. Further clinical trials with the identification of the subgroup of ASD patients that would benefit from carnitine administration are warranted.

Maternal folic acid and micronutrient supplementation is associated with vitamin levels and symptoms in children with autism spectrum disorders

To explore possible associations between maternal use of micronutrient supplements and the subsequent vitamin levels and symptoms in offspring with autism spectrum disorder (ASD), a total of 416 children with ASD and 201 typically developing (TD) children were enrolled. The children born to mothers without folic acid (FA) and micronutrient supplementation during pregnancy had more severe social cognition impairments, social communication impairments, autism behaviour mannerisms, developmental delays in adaptive and gross motor behaviour and gastrointestinal problems than children born to mothers who used FA and micronutrient supplements (P＜0.05). Interestingly, there was an association between maternal micronutrient supplementation and vitamin A (VA), vitamin D (VD) and folate levels in the ASD children (P<0.05), and levels of these vitamins also were associated with symptoms of ASD. Maternal FA and/or micronutrient supplementation may potentially moderate the symptoms of ASD. Interrupting the chain of micronutrient deficiencies between pregnant mothers and children may be beneficial in improving symptoms of ASD.