Perinatal folate-related exposures and risk of psychotic symptoms in the ALSPAC birth cohort

Personal and contextual components of resilience mediate risky family environment's effect on psychotic-like experiences

BACKGROUND

Psychotic-like experiences (PLEs) index an increased risk for subsequent psychotic disorders. A risky family environment is a well-established risk factor for PLEs; however, different contextual and personal resiliency factors may differentially mediate its effect on PLEs.

OBJECTIVE

In this study, we propose a two-dimensional model of resilience. Our aim is to address separately the mediational role of personal and contextual resiliency factors between a risky family environment and PLEs in a community sample.

METHODS AND MATERIALS

Five-hundred University students completed an on-line questionnaire, including the Resilience Scale for Adults (RSA), the 16-item version of the Prodromal Questionnaire (iPQ-16) and the Risky Family Questionnaire (RFQ). Mediation was assessed using Structural Equation Modelling with bootstrapping estimation of indirect effect.

RESULTS

The direct effects of personal and contextual resilience on PLEs were respectively -0.69 [-0.97, -0.41] (P < .001) and - 0.19 [-0.58, 0.20] (ns); the indirect effect through personal resilience was 0.03[0.01, 0.04] (P < .001). Personal resilience mediated 27.4% of the total effect of risky family environment on PLEs.

DISCUSSION

Personal resilience, as opposite to contextual resilience, mediates the effect of a risky family environment on PLEs. Low personal resilience may represent an individual risk factor that transmits the effect of risky family environment on PLEs and could represent a central aspect of individualized prevention and treatment strategies.

Markers of Psychosis Risk in the General Population

The categorical approach to defining schizophrenia spectrum disorders requires meeting established criteria. To advance early identification and intervention in young people, the field has progressed to studying help-seeking individuals who are at clinical high risk based on subthreshold psychosis spectrum symptoms, and criteria have been articulated for qualifying individuals as at risk. A broader dimensional examination of psychosis has been applied to population-based studies on non-help seekers. This review highlights the ascertainment and assessment approaches to such population-based studies. Most studies are cross-sectional and rely on questionnaires with limited overlap of tools. However, several consistent findings emerge on symptoms, neurocognitive deficits, and neuroimaging parameters and other biomarkers associated with emergence and persistence of psychotic features. The findings are consistent with the literature on abnormalities associated with schizophrenia, including the presence of neurocognitive deficits; abnormalities in brain structure, function, and connectivity that are related to distress; impairment; and functional outcome. These findings support the validity of studying psychosis experiences during development in a way that can chart the emergence of psychosis in the context of general psychopathology. Such studies are necessary for establishing developmental trajectories that characterize this emergence and for identifying risk and resilience biomarkers moderating or modulating the full range of schizophrenia-related manifestations. More community-based studies are needed, with better standardization and harmonization of measures and incorporating longitudinal follow-up, to establish mechanistic links between cellular-molecular aberrations and specific manifestations of psychosis as envisioned by the precision medicine agenda.

[The study of the association between the C677T polymorphism of the methylenetetrahydrofolate reductase gene and severity of symptoms in patients with schizophrenia]

OBJECTIVE

To study the association of the C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene with the risk of schizophrenia in a large sample, including schizophrenic patients and mentally healthy people, and to investigate the relationship of this polymorphism with the severity of schizophrenia symptoms and genotype-environment interaction effects on these symptoms.

MATERIAL AND METHODS

The sample for genotyping consisted of 1357 patients with schizophrenia and schizophrenia spectrum disorders and 711 people of the control group. The severity of symptoms was assessed with the PANSS. Obstetrical complications and a traumatic brain injury in medical history were studied as environmental factors.

RESULTS AND CONCLUSION

No association was found between MTHFR C677T polymorphism and schizophrenia. There was no genotype effect on the severity of symptoms on the PANSS subscales. The effect of genotype-environment interactions on the severity of schizophrenia symptoms was not detected. The results do not confirm the data of a number of studies on the relationship of MTHFR C677T polymorphism with schizophrenia symptoms.

The impact of folic acid supplementation on gestational and long term health: Critical temporal windows, benefits and risks

Highlights

Associations between FA supplementation in pregnancy and effects on offspring's NTDs, allergy/respiratory problems, cancer and behaviour problems as been studied.There is growing concern about the effects of excessive FA supplementation, whether in terms of doses or times of exposure.FA supplementation in the periconceptional period is protective against NTDs while in later periods it could be deleterious.A daily dose of 0.4 mg FA in the periconceptional period seems to be effective and safe.

Abstract

Maternal folic acid (FA) supplementation is one of the most popular nutritional interventions during pregnancy for its protective effect against neural tube defects (NTDs).The purposes of this review are: (a) to gather the current evidence regarding supplementation of maternal diet with FA and (b) to problematize the available literature in terms of dosages, critical temporal windows, and its potential benefits and risks.The expression (pregnancy OR fetus OR offspring OR mother) AND ("folic acid" AND supplementation) was searched on PubMed database, filtering for articles published from 2005 to 2014. Publications referring to FA supplementation during the periconceptional period or pregnancy in which there was a conclusion about the effects of isolated FA supplementation on pregnant woman, pregnancy or offspring were included. Of the initial 1182 papers, 109 fulfilled the inclusion criteria.The majority of the publications reported FA supplementation outcomes on offspring's health, with emphasis in NTDs, allergy/respiratory problems, cancer and behaviour problems. Some inconsistency is observed on the impact of FA supplementation on different outcomes, except for NTDs. It is also visible an increased concern about the impact of excessive supplementation, either in terms of doses or exposure's duration.In conclusion, there is a growing interest in FA supplementation issues. The protective effect of FA supplementation over NTDs has been confirmed, being the periconceptional period a critical window, and it is frequently suggested that allergy/respiratory outcomes arise from (excessive) FA supplementation particularly later in pregnancy. Further research on critical doses and time of exposure should be conducted.

New Perspective on Impact of Folic Acid Supplementation during Pregnancy on Neurodevelopment/Autism in the Offspring Children - A Systematic Review

It has been conclusively established that folic acid supplementation prior to and during early pregnancy (up to 12 weeks of gestation) can prevent neural tube defects (NTDs). We hypothesized that folate effects may extend from neuro-structural defects to alterations in neuro-behavioural and emotional skills including autism spectrum disorders (ASDs) and other developmental disorders. The objective of this review was to comprehensively evaluate evidence on the impact of folic acid on neurodevelopment other than NTDs. We conducted an online search of relevant literature compiled by the National Library of Medicine from Medline and EMBASE (searched on Dec 31, 2014: http://www.ncbi.nlm.nih.gov/entrez/query/fcgi and http://www.elsevier.com/online-tools/embase). We first created 3 files (search restricted to English literature) using the following key words: 1) folate or folic acid (171322 papers identified by this search); 2) maternal or pregnancy or pregnant or gestation or gestational or prenatal or antenatal or periconception or periconceptional (1349219 papers identified by this search); and 3) autism or autism spectrum disorders or developmental delay or development or neurodevelopment or mental or cognitive or language or personal-social or gross motor or fine motor or behaviour or intellectual or intelligence or Bayley Scale (8268145 papers identified by this search). We then merged the 3 files and reviewed the papers that addressed these three issues simultaneously. A total of 22 original papers that examined the association between folic acid supplementation in human pregnancy and neurodevelopment/autism were identified after the screening, with 15 studies showing a beneficial effect of folic acid supplementation on neurodevelopment/autism, 6 studies showed no statistically significant difference, while one study showed a harmful effect in > 5 mg folic acid supplementation/day during pregnancy. Folic acid supplementation in pregnancy may have beneficial effects on the neurodevelopment of children beyond its proven effect on NTDs.

Animal models of gene-environment interaction in schizophrenia: A dimensional perspective

Schizophrenia has long been considered as a disorder with multifactorial origins. Recent discoveries have advanced our understanding of the genetic architecture of the disease. However, even with the increase of identified risk variants, heritability estimates suggest an important contribution of non-genetic factors. Various environmental risk factors have been proposed to play a role in the etiopathogenesis of schizophrenia. These include season of birth, maternal infections, obstetric complications, adverse events at early childhood, and drug abuse. Despite the progress in identification of genetic and environmental risk factors, we still have a limited understanding of the mechanisms whereby gene-environment interactions (G × E) operate in schizophrenia and psychoses at large. In this review we provide a critical analysis of current animal models of G × E relevant to psychotic disorders and propose that dimensional perspective will advance our understanding of the complex mechanisms of these disorders.

The Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort as a resource for studying psychopathology in childhood and adolescence: a summary of findings for depression and psychosis

PURPOSE

The purpose of this study is to highlight the Avon Longitudinal Study of Parents and Children (ALSPAC) as a resource to study psychopathology. To demonstrate this, we review the studies related to depression and psychosis in childhood and adolescence and discuss the results in relation to the aetiology of depression and psychotic experiences (PEs) and possible underlying mechanisms.

METHODS

We examined the list of publications from ALSPAC and then classified them as examining (a) the course and risk factors of maternal and paternal depression, (b) the effects of maternal and paternal depression on child development, (c) risk factors for depression in childhood and adolescence, (d) the frequency, clinical relevance and risk factors of PEs, and (e) shared risk factors for depression and PEs.

RESULTS

There was evidence that environmental stressors and the way these are interpreted contribute to risk of depression and evidence that biological factors related to puberty are also likely to play a role. With regards to PEs, the findings further support the existence of 'a continuum of psychosis' while they also suggest that PEs might be of limited clinical utility in predicting psychotic disorder during adolescence and early adulthood. Finally, most risk factors examined were found to be shared between depression and PEs.

CONCLUSIONS

The ALSPAC birth cohort has provided important insights for our understanding of the aetiological mechanisms underlying depression and PEs. Future research could aim to incorporate measures of automatic psychological mechanisms to provide insights into the brain mechanisms that underlie these clinical phenomena.

Maternal lifestyle during pregnancy and child psychomotor development - Polish Mother and Child Cohort study

BACKGROUND

Nowadays special attention is paid to prenatal exposures to maternal lifestyle factors and their impact on a child development.

AIM

The objective of this study was to evaluate the impact of modifiable maternal lifestyle factors on child neurodevelopment based on the Polish Mother and Child Cohort study.

MATERIAL AND METHODS

The current analysis included 538 mother-child pairs. The following factors related to maternal lifestyle were considered: smoking and environmental tobacco smoke (ETS) exposure (based on the cotinine level in maternal saliva measured using LC-ESI+MS/MS method), alcohol consumption and leisure-time physical activity (LTPA) in pregnancy, pre-pregnancy BMI, and folic acid supplementations before and during pregnancy based on questionnaire data. Psychomotor development was assessed in children at the ages of one and two by the Bayley Scales of Infant and Toddler Development.

RESULTS

Significant association was observed between prenatal exposure to tobacco constituents and a decreased child motor development in assessments performed at both ages (β=-0.8, p=0.01; β=-1.4, p<0.001). Maternal pre-pregnancy underweight was associated with decreased language abilities at 12 months of age (β=-5.2, p=0.01) and cognitive and motor development at 24 months of age, for which the associations were of borderline significance (p=0.06). The recommended level of LTPA during pregnancy was beneficial for child language development at two years of age (β=4.8, p=0.02). For alcohol and folic acid consumption there were no significant associations with any of the analyzed domains of child neurodevelopment.

CONCLUSIONS

Children prenatally exposed to tobacco compounds and those of underweight mothers had a decreased psychomotor development. The recommended level of LTPA during pregnancy had positive impact on child development. These results underscore the importance of policies and public health interventions promoting healthy lifestyle among women in reproductive age and during pregnancy.

The secret language of destiny: stress imprinting and transgenerational origins of disease

Epigenetic regulation modulates gene expression without altering the DNA sequence to facilitate rapid adjustments to dynamically changing environmental conditions. The formation of an epigenetic memory allows passing on this information to subsequent generations. Here we propose that epigenetic memories formed by adverse environmental conditions and stress represent a critical determinant of health and disease in the F3 generation and beyond. Transgenerational programming of epigenetic regulation may represent a key to understand adult-onset complex disease pathogenesis and cumulative effects of life span and familial disease etiology. Ultimately, the mechanisms of generating an epigenetic memory may become of potentially promising diagnostic and therapeutic relevance due to their reversible nature. Exploring the role of environmental factors, such as stress, in causing variations in epigenetic profiles may lead to new avenues of personalized, preventive medicine based on epigenetic signatures and interventions.

Maternal folate status in early pregnancy and child emotional and behavioral problems: the Generation R Study

BACKGROUND

Maternal prenatal folate status has been linked to neurodevelopmental disorders, but the association with child emotional and behavioral problems is unclear.

OBJECTIVES

We assessed the association of maternal folate status during pregnancy with child emotional and behavioral problems. Also, we examined whether any association between folate status and child problems is a consequence of maternal folic acid supplement use or variation in maternal MTHFR genotype.

DESIGN

Within a population-based cohort, we measured maternal plasma folate concentrations in early pregnancy and assessed folic acid supplement use by questionnaire. Mothers of European descent were genotyped for the MTHFR 677 C→T polymorphism. Child emotional and behavioral problems were assessed with the Child Behavior Checklist at 3 y in 3209 children.

RESULTS

Children of mothers with prenatal folate deficiency were at higher risk of emotional problems (OR: 1.57; 95% CI: 1.03, 2.38) but not behavioral problems (OR: 1.00; 95% CI: 0.64, 1.56) after adjustment for confounders. A higher risk of emotional problems was also found in children whose mothers started using folic acid supplements late or did not use supplements at all (OR: 1.45; 95% CI: 1.14, 1.84) than in children whose mothers started periconceptionally. However, low plasma folate concentrations only partly explained this association (OR: 1.38; 95% CI: 1.08, 1.78). Although related to plasma folate concentrations, maternal MTHFR genotype did not explain the association of folate status with offspring emotional problems.

CONCLUSION

Low maternal folate status during early pregnancy is associated with a higher risk of emotional problems in the offspring.

Prenatal nutrition, epigenetics and schizophrenia risk: can we test causal effects?

We posit that maternal prenatal nutrition can influence offspring schizophrenia risk via epigenetic effects. In this article, we consider evidence that prenatal nutrition is linked to epigenetic outcomes in offspring and schizophrenia in offspring, and that schizophrenia is associated with epigenetic changes. We focus upon one-carbon metabolism as a mediator of the pathway between perturbed prenatal nutrition and the subsequent risk of schizophrenia. Although post-mortem human studies demonstrate DNA methylation changes in brains of people with schizophrenia, such studies cannot establish causality. We suggest a testable hypothesis that utilizes a novel two-step Mendelian randomization approach, to test the component parts of the proposed causal pathway leading from prenatal nutritional exposure to schizophrenia. Applied here to a specific example, such an approach is applicable for wider use to strengthen causal inference of the mediating role of epigenetic factors linking exposures to health outcomes in population-based studies.