Folic acid as an adjunct in the treatment of children with the autism fragile-X syndrome (AFRAX)

A Scoping Literature Review of the Relation between Nutrition and ASD Symptoms in Children

Autism spectrum disorder (ASD) is characterized by impairments in social interaction, communication skills, and repetitive and restrictive behaviors and interests. Even though there is a biological basis for an effect of specific nutrition factors on ASD symptoms and there is scientific literature available on this relationship, whether nutrition factors could play a role in ASD treatment is unclear. The goal of the current literature review was to summarize the available scientific literature on the relation between nutrition and autism spectrum disorder (ASD) symptoms in childhood, and to formulate practical dietary guidelines. A comprehensive search strategy including terms for ASD, nutrition factors (therapeutic diets, dietary patterns, specific food products, fatty acids and micronutrients) and childhood was developed and executed in six literature databases (Cinahl, Cochrane, Ovid Embase, PsycInfo, PubMed and Web of Science). Data from meta-analyses, systematic reviews and original studies were qualitatively summarized. A total of 5 meta-analyses, 29 systematic reviews and 27 original studies were retrieved that focused on therapeutic diets, specific food products, fatty acids and micronutrients and ASD symptoms during childhood. Results of the available studies were sparse and inconclusive, and hence, no firm conclusions could be drawn. There is currently insufficient evidence for a relation between nutrition and ASD symptoms in childhood, making it impossible to provide practical nutrition guidelines; more methodological sound research is needed.

Cerebral Folate Deficiency, Folate Receptor Alpha Autoantibodies and Leucovorin (Folinic Acid) Treatment in Autism Spectrum Disorders: A Systematic Review and Meta-Analysis

The cerebral folate receptor alpha (FRα) transports 5-methyltetrahydrofolate (5-MTHF) into the brain; low 5-MTHF in the brain causes cerebral folate deficiency (CFD). CFD has been associated with autism spectrum disorders (ASD) and is treated with d,l-leucovorin (folinic acid). One cause of CFD is an autoantibody that interferes with the function of the FRα. FRα autoantibodies (FRAAs) have been reported in ASD. A systematic review was performed to identify studies reporting FRAAs in association with ASD, or the use of d,l-leucovorin in the treatment of ASD. A meta-analysis examined the prevalence of FRAAs in ASD. The pooled prevalence of ASD in individuals with CFD was 44%, while the pooled prevalence of CFD in ASD was 38% (with a significant variation across studies due to heterogeneity). The etiology of CFD in ASD was attributed to FRAAs in 83% of the cases (with consistency across studies) and mitochondrial dysfunction in 43%. A significant inverse correlation was found between higher FRAA serum titers and lower 5-MTHF CSF concentrations in two studies. The prevalence of FRAA in ASD was 71% without significant variation across studies. Children with ASD were 19.03-fold more likely to be positive for a FRAA compared to typically developing children without an ASD sibling. For individuals with ASD and CFD, meta-analysis also found improvements with d,l-leucovorin in overall ASD symptoms (67%), irritability (58%), ataxia (88%), pyramidal signs (76%), movement disorders (47%), and epilepsy (75%). Twenty-one studies (including four placebo-controlled and three prospective, controlled) treated individuals with ASD using d,l-leucovorin. d,l-Leucovorin was found to significantly improve communication with medium-to-large effect sizes and have a positive effect on core ASD symptoms and associated behaviors (attention and stereotypy) in individual studies with large effect sizes. Significant adverse effects across studies were generally mild but the most common were aggression (9.5%), excitement or agitation (11.7%), headache (4.9%), insomnia (8.5%), and increased tantrums (6.2%). Taken together, d,l-leucovorin is associated with improvements in core and associated symptoms of ASD and appears safe and generally well-tolerated, with the strongest evidence coming from the blinded, placebo-controlled studies. Further studies would be helpful to confirm and expand on these findings.

Epigenetics of the developing and aging brain: Mechanisms that regulate onset and outcomes of brain reorganization

Brain development is a life-long process that encompasses several critical periods of transition, during which significant cognitive changes occur. Embryonic development, puberty, and reproductive senescence are all periods of transition that are hypersensitive to environmental factors. Rather than isolated episodes, each transition builds upon the last and is influenced by consequential changes that occur in the transition before it. Epigenetic marks, such as DNA methylation and histone modifications, provide mechanisms by which early events can influence development, cognition, and health outcomes. For example, parental environment influences imprinting patterns in gamete cells, which ultimately impacts gene expression in the embryo which may result in hypersensitivity to poor maternal nutrition during pregnancy, raising the risks for cognitive impairment later in life. This review explores how epigenetics induce and regulate critical periods, and also discusses how early environmental interactions prime a system towards a particular health outcome and influence susceptibility to disease or cognitive impairment throughout life.

Repurposing available drugs for neurodevelopmental disorders: The fragile X experience

Many available drugs have been repurposed as treatments for neurodevelopmental disorders. In the specific case of fragile X syndrome, many clinical trials of available drugs have been conducted with the goal of disease modification. In some cases, detailed understanding of basic disease mechanisms has guided the choice of drugs for clinical trials, and several notable successes in fragile X clinical trials have led to common use of drugs such as minocycline in routine medical practice. Newer technologies like Disease-Gene Expression Matching (DGEM) may allow for more rapid identification of promising repurposing candidates. A DGEM study predicted that sulindac could be therapeutic for fragile X, and subsequent preclinical validation studies have shown promising results. The use of combinations of available drugs and nutraceuticals has the potential to greatly expand the options for repurposing, and may even be a viable business strategy. This article is part of the Special Issue entitled 'Drug Repurposing: old molecules, new ways to fast track drug discovery and development for CNS disorders'.

WFIKKN1 and WFIKKN2: "Companion" proteins regulating TGFB activity

The WFIKKN (WAP, Follistatin/kazal, Immunoglobulin, Kunitz and Netrin domain-containing) protein family is composed of two multidomain proteins: WFIKKN1 and WFIKKN2. They were formed by domain shuffling and are likely present in deuterostoms. The WFIKKN (also called GASP) proteins are well known for their function in muscle and skeletal tissues, namely, inhibition of certain members of the transforming growth factor beta (TGFB) superfamily such as myostatin (MSTN) and growth and differentiation factor 11 (GDF11). However, the role of the WFIKKN proteins in other tissues is still poorly understood in spite of evidence suggesting possible action in the inner ear, brain and reproduction. Further, several recent studies based on next generation technologies revealed differential expression of WFIKKN1 and WFIKKN2 in various tissues suggesting that their function is not limited to MSTN and GDF11 inhibition in musculoskeletal tissue. In this review, we summarize current knowledge about the WFIKKN proteins and propose that they are "companion" proteins for various growth factors by providing localized and sustained presentation of TGFB proteins to their respective receptors, thus regulating the balance between the activation of Smad and non-Smad pathways by TGFB.

Single-base resolution of mouse offspring brain methylome reveals epigenome modifications caused by gestational folic acid

Background

Epigenetic modifications, such as cytosine methylation in CpG-rich regions, regulate multiple functions in mammalian development. Maternal nutrients affecting one-carbon metabolism during gestation can exert long-term effects on the health of the progeny. Using C57BL/6 J mice, we investigated whether the amount of ingested maternal folic acid (FA) during gestation impacted DNA methylation in the offspring’s cerebral hemispheres. Reduced representation bisulfite sequencing at single-base resolution was performed to analyze genome-wide DNA methylation profiles.

Results

We identified widespread differences in the methylation patterns of CpG and non-CpG sites of key developmental genes, including imprinted and candidate autism susceptibility genes (P <0.05). Such differential methylation of the CpG and non-CpG sites may use different mechanisms to alter gene expressions. Quantitative real time reverse transcription-polymerase chain reaction confirmed altered expression of several genes.

Conclusions

These finding demonstrate that high maternal FA during gestation induces substantial alteration in methylation pattern and gene expression of several genes in the cerebral hemispheres of the offspring, and such changes may influence the overall development. Our findings provide a foundation for future studies to explore the influence of gestational FA on genetic/epigenetic susceptibility to altered development and disease in offspring.

Folic acid for fragile X syndrome

BACKGROUND

It has been argued that individuals with fragile X syndrome could have low folate levels in their bodies and that supplementing their dietary intake might remediate the adverse developmental and behavioural effects of the condition.

OBJECTIVES

To review the efficacy and safety of folic acid in the treatment of people with fragile X syndrome.

SEARCH STRATEGY

We searched four databases in November 2010: CENTRAL, PubMed, EMBASE and PsycINFO.

SELECTION CRITERIA

Randomised controlled trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias using the Cochrane 'Risk of bias' tool.

MAIN RESULTS

We included five trials, which were published between 1986 and 1992. Overall, they included 67 patients, all male, with ages ranging from one to 54 years. Intellectual disability in participants varied from borderline to severe and some studies included patients with an additional diagnosis of autism or autistic behaviour. Four of the studies were placebo-controlled cross-over trials and one study was a parallel design. The duration of follow-up ranged from two months to 12 months and the period on folic acid or placebo ranged from two to eight months. Doses of folic acid ranged from 10 mg to 250 mg per day, 10 mg per day being the most common. Most of the younger patients involved were also taking part in special education programmes (usually involving language and occupational therapy).We were not able to perform meta-analysis to combine results but none of the individual studies found evidence of clinical benefit with the use of folic acid medication in fragile X syndrome patients on any of the areas of interest, either psychological and learning capabilities or behaviour and social performance, as measured with standardised tools. Separate analysis of evidence for patients of different age groups, i.e. prepubertal children and postpubertal young people, found some statistically significant results, but did not show clear evidence of benefit for either group. Adverse effects of folic acid treatment were rare, not serious and transient.Studies were generally poorly reported and we classified only one study as being at low risk of bias.

AUTHORS' CONCLUSIONS

The quality of available evidence is low and not suitable for drawing conclusions about the effect of folic acid on fragile X syndrome patients. It consists of few studies with small samples of patients, all of them male, with little statistical power to detect anything other than huge effects.

Treatments for fragile X syndrome: a closer look at the data

Research into the determinants and developmental course of fragile X syndrome (FXS) has made remarkable progress over the last 25 years. However, treatments to ameliorate the symptoms of FXS have been less forthcoming. While there is optimism in the field that the pace of intervention research is quickening, there has been a bias toward psychopharmacological approaches to treatment. A closer look at the data from those investigations reveals a paucity of evidence that medications can improve intellectual and adaptive functioning in FXS, or decrease associated behavioral and/or emotional issues. Work in other related disorders (e.g., autism) has shown that dramatic improvements in intellectual and adaptive functioning, as well as behavioral and emotional problems, can occur if intensive behavioral treatment is begun early in the child's life. It is hoped that future research efforts will evaluate these intensive early intervention strategies in children with FXS, perhaps in combination with pharmacological approaches.

Systematic review of pharmacological treatments in fragile X syndrome

Background

Fragile X syndrome (FXS) is considered the most common cause of inherited mental retardation. Affected people have mental impairment that can include Attention Deficit and/or Hyperactivity Disorder (ADHD), autism disorder, and speech and behavioural disorders. Several pharmacological interventions have been proposed to treat those impairments.

Methods

Systematic review of the literature and summary of the evidence from clinical controlled trials that compared at least one pharmacological treatment with placebo or other treatment in individuals with diagnosis of FXS syndrome and assessed the efficacy and/or safety of the treatments. Studies were identified by a search of PubMed, EMBASE and the Cochrane Databases using the terms fragile X and treatment. Risk of bias of the studies was assessed by using the Cochrane Collaboration criteria.

Results

The search identified 276 potential articles and 14 studies satisfied inclusion criteria. Of these, 10 studies on folic acid (9 with crossover design, only 1 of them with good methodological quality and low risk of bias) did not find in general significant improvements. A small sample size trial assessed dextroamphetamine and methylphenidate in patients with an additional diagnosis of ADHD and found some improvements in those taking methylphenidate, but the length of follow-up was too short. Two studies on L-acetylcarnitine, showed positive effects and no side effects in patients with an additional diagnosis of ADHD. Finally, one study on patients with an additional diagnosis of autism assessed ampakine compound CX516 and found no significant differences between treatment and placebo. Regarding safety, none of the studies that assessed that area found relevant side effects, but the number of patients included was too small to detect side effects with low incidence.

Conclusion

Currently there is no robust evidence to support recommendations on pharmacological treatments in patients with FXS in general or in those with an additional diagnosis of ADHD or autism.

A factor analytic study of the Autism Behavior Checklist

The factor structure of the Autism Behavior Checklist (ABC) (Krug, Arick, & Almond, 1980a, 1980b), a 57-item screening instrument for autism, was examined on a sample of 383 individuals with autism spectrum disorders (i.e., autistic disorder, Asperger syndrome, and other autism-like conditions) aged 5-22 years. A five-factor model accounted for 80% of the total variance in the checklist. Thirty-nine of the 57 items had factor loadings of 0.4 or more, with 13 items loading on Factor 1, 11 items on Factor 2, 6 items on Factor 3, 5 items on Factor 4, and 4 items on Factor 5. No support was found for classifying the 57 items into the five subscales proposed by Krug et al. (1980a, 1980b) or for the three-factor solution suggested by Wadden, Bryson, and Rodger (1991).

Psychopharmacology in autism

Autism is a neurobiological disorder. The core clinical features of autism include impairment in social interaction, impairments in verbal and nonverbal communication, and restricted, repetitive, and stereotyped patterns of behavior, interests, and activities. Autism often has coexisting neuropsychiatric disorders, including seizure disorders, attention deficit hyperactivity disorder, affective disorders, anxiety disorder, obsessive-compulsive disorder, and Tourette disorder. No etiology-based treatment modality has been developed to cure individuals with autism. However, comprehensive intervention, including parental counseling, behavior modification, special education in a highly structured environment, sensory integration training, speech therapy, social skill training, and medication, has demonstrated significant treatment effects in many individuals with autism. Findings from preliminary studies of major neurotransmitters and other neurochemical agents strongly suggest that neurochemical factors play a major role in autism. The findings also provide the rationale for psychopharmacotherapy in individuals with autism. This article reviews studies of neurochemical systems and related psychopharmacological research in autism and related neuropsychiatric disorders. Clinical indications for pharmacotherapy are described, and uses of various medications are suggested. This article also discusses new avenues of investigation that may lead to the development of more effective medication treatments in persons with autism.

High-dose pyridoxine and magnesium administration in children with autistic disorder: an absence of salutary effects in a double-blind, placebo-controlled study

Several reports have described salutary effects such as decreased physical aggression and improved social responsiveness being associated with the administration of high doses of pyridoxine and magnesium (HDPM) in open-labeled and controlled studies of patients with autism. Despite this fact, this intervention remains controversial. A 10-week double-blind, placebo-controlled trial was undertaken to examine both the efficacy and safety of HDPM in autism. Twelve patients were enrolled, and 10 patients (mean age 6 years 3 months) were able to complete the study. HDPM at an average dose of 638.9 mg of pyridoxine and 216.3 mg of magnesium oxide was ineffective in ameliorating autistic behaviors as assessed by the Children's Psychiatric Rating Scale (CPRS), the Clinical Global Impression Scale, and the NIMH Global Obsessive Compulsive Scale. Furthermore, no clinically significant side effects were noted during HDPM administration. A trend for a transient change on the CPRS was found that was possibly due to a placebo response. This study raises doubts about the clinical effectiveness of HDPM in autistic disorder.

A comparison of speaking and mute individuals with autism and autistic-like conditions on the Autism Behavior Checklist

The item, total, and subscale scores on the Autism Behavior Checklist (ABC) were compared for 155 mute and 335 speaking individuals with autism spectrum disorders. Although no significant difference was observed between the groups on the ABC total score, the mute group demonstrated significantly more pathology on 21 of 57 items and 3 of 5 subscales. The speaking group obtained significantly higher scores on only 8 items and 1 subscale (Language). The appropriateness of providing greater pathology scores on expressive language items to speaking, rather than to mute, individuals is called into question. The authors speculate whether the expressive language items are weighted too heavily, in regard both to the Language subscale and to the ABC total score. If the expressive language items were removed, the mute group would have significantly higher ABC total scores and therefore a greater degree of autism severity.

Psychiatry and mental retardation: towards a behavioural pharmacological concept

The rediscovery of psychiatric disorders in mentally retarded subjects has revealed the inadequacy of existing diagnostic and classification systems. The major reason for the limitations of the latter is that such systems have not been developed for application in subjects with substantial intellectual handicaps or other brain dysfunctions. Furthermore, the impact of the different aetiological brain factors is more or less neglected, and so are the specific interrelations between brain dysfunctions and psychiatric symptoms. For a better understanding of the behavioural disorders in mentally retarded subjects, the data from primate studies should be taken into consideration, especially where these suggest a relationship between developmental factors and brain dysfunction. Finally, a functional approach is advocated, linking biological and psychological dysfunctions, that could eventually lead to a so-called functional psychopharmacology.

Double-blind, placebo-controlled crossover study of folinic acid (Leucovorin for the treatment of fragile X syndrome

We conducted a randomized, double-blind, placebo-controlled crossover study of folinic acid therapy (dl-Leucovorin, 15 mg/day) or placebo for males with Fragile X (fra(x)) syndrome. Twenty-one patients were enrolled in the study. The treatment periods were 3 months in length. Patients were followed with chemistry panels and complete blood counts. No differences between placebo and treatment phases were noted in any laboratory parameter. Instruments to measure functioning were the Vineland Adaptive Behavioral Scales, Peabody Picture Vocabulary Test-Revised, Conners Parent and Teaching Rating Scales, the ADD-H: Comprehensive Teacher's Rating Scales (ACTeRS), and a questionnaire designed by the investigators. At the crossover point, 2 parents requested to withdraw from the study because they felt their children had made dramatic gains during the first half of the study and had lost those gains after the crossover point. Both parents had accurately predicted that their sons were receiving folinic acid during the first half of the study. However, no statistically significant differences could be demonstrated between the treatment and placebo phases of the study with any instrument when the results were averaged over the entire cohort. After the conclusion of the study, approximately one-half of the parents believed that their children had benefitted from the folinic acid therapy and elected to continue treatment. Thus far, no significant side effects have been noted from long-term folinic acid therapy so we are offering all Fragile X patients a 3-month trial of medication.

Fenfluramine treatment of twenty children with autism

The effects of fenfluramine were examined on 20 children with autism over a 48-week period utilizing a double-blind placebo-controlled crossover design. Blood and urine samples and psychological tests (Griffith's Developmental Scales and Real Life Rating Scale) were obtained at each crossover period. The only significant improvement was a decrease in abnormal motor behavior. We did not find any significant improvement in intellectual functioning or any correlation between good clinical response and low baseline serotonin levels or high baseline IQ. Serotonin decreased 53% after fenfluramine treatment and rebounded to a level 35% higher than baseline following a placebo period. Fenfluramine and the active metabolite norfenfluramine were determined in plasma samples.

Folic acid treatment of fragile X males: a further study

Investigations of the effect of high dose folic acid treatment of fragile X syndrome in males has produced mixed results. However, no study had examined the possible drug effects of folic acid on non-fragile X control males. Therefore, we examined the effect of folic acid on fragile X males using non-fragile X control males. Subjects were assigned randomly to an ABA or BAB design. Duration of either folic acid or placebo condition was 4 months. Folic acid or placebo was given in a double-blind fashion. At the end of each condition, the subjects' behavior was assessed. At the end of the study, parents were asked to complete a questionnaire. Using parents' responses, we examined 22 items on the Autistic Descriptors Checklist and two subscales from the Vineland Adaptive Behavior Scale which corresponded to areas of behavior parents' noted to have shown improvement. We did not find significant differences between fragile X males and control males, within subjects, nor across folic acid and placebo conditions. Thus, our follow-up study confirms and extends our original findings, as well as those of other researchers: namely, that no dramatic changes in behavior result from high dose folic acid. Moreover, subtle improvements observed in earlier investigations were not confirmed.