Maternal polyunsaturated fatty acids during pregnancy and offspring brain development in childhood

Nutraceuticals in Psychiatric Disorders: A Systematic Review

Correct nutrition and diet are directly correlated with mental health, functions of the immune system, and gut microbiota composition. Diets with a high content of some nutrients, such as fibers, phytochemicals, and short-chain fatty acids (omega-3 fatty acids), seem to have an anti-inflammatory and protective action on the nervous system. Among nutraceuticals, supplementation of probiotics and omega-3 fatty acids plays a role in improving symptoms of several mental disorders. In this review, we collect data on the efficacy of nutraceuticals in patients with schizophrenia, autism spectrum disorders, major depression, bipolar disorder, and personality disorders. This narrative review aims to provide an overview of recent evidence obtained on this topic, pointing out the direction for future research.

Nutritional Quality Implications: Exploring the Impact of a Fatty Acid-Rich Diet on Central Nervous System Development

Given the comprehensive examination of the role of fatty acid-rich diets in central nervous system development in children, this study bridges significant gaps in the understanding of dietary effects on neurodevelopment. It delves into the essential functions of fatty acids in neurodevelopment, including their contributions to neuronal membrane formation, neuroinflammatory modulation, neurogenesis, and synaptic plasticity. Despite the acknowledged importance of these nutrients, this review reveals a lack of comprehensive synthesis in current research, particularly regarding the broader spectrum of fatty acids and their optimal levels throughout childhood. By consolidating the existing knowledge and highlighting critical research gaps, such as the effects of fatty acid metabolism on neurodevelopmental disorders and the need for age-specific dietary guidelines, this study sets a foundation for future studies. This underscores the potential of nutritional strategies to significantly influence neurodevelopmental trajectories, advocating an enriched academic and clinical understanding that can inform dietary recommendations and interventions aimed at optimizing neurological health from infancy.

Association between interpregnancy interval and risk of autism spectrum disorder: a systematic review and Bayesian network meta-analysis

Although the risk of autism spectrum disorder (ASD) has been reported to be associated with interpregnancy intervals (IPIs), their association remains debatable due to inconsistent findings in existing studies. Therefore, the present study aimed to explore their association. PubMed, Embase, Web of Science, and the Cochrane Library were systematically retrieved up to May 25, 2022. An updated search was performed on May 25, 2023, to encompass recent studies. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS). Our primary outcome measures were expressed as adjusted odds ratios (ORs). Given various control measures for IPI and diverse IPI thresholds in the included studies, a Bayesian network meta-analysis was performed. Eight studies were included, involving 24,865 children with ASD and 2,890,289 children without ASD. Compared to an IPI of 24 to 35 months, various IPIs were significantly associated with a higher risk of ASD (IPIs < 6 months: OR = 1.63, 95% CI 1.53-1.74, n = 5; IPIs of 6-11 months: OR = 1.50, 95% CI 1.42-1.59, n = 4; IPIs of 12-23 months: OR = 1.19, 95% CI 1.12-1.23, n = 10; IPIs of 36-59 months: OR = 0.96, 95% CI 0.94-0.99, n = 2; IPIs of 60-119 months: OR = 1.15, 95% CI 1.10-1.20, n = 4; IPIs > 120 months: OR = 1.57, 95% CI 1.43-1.72, n = 4). After adjusting confounding variables, our analysis delineated a U-shaped restricted cubic spline curve, underscoring that both substantially short (< 24 months) and excessively long IPIs (> 72 months) are significantly correlated with an increased risk of ASD.  Conclusion: Our analysis indicates that both shorter and longer IPIs might predispose children to a higher risk of ASD. Optimal childbearing health and neurodevelopmental outcomes appear to be associated with a moderate IPI, specifically between 36 and 60 months. What is Known: • An association between autism spectrum disorder (ASD) and interpregnancy intervals (IPIs) has been speculated in some reports. • This association remains debatable due to inconsistent findings in available studies. What is New: • Our study delineated a U-shaped restricted cubic spline curve, suggesting that both shorter and longer IPIs predispose children to a higher risk of ASD. • Optimal childbearing health and neurodevelopmental outcomes appear to be associated with a moderate IPI, specifically between 36 and 60 months.

Optimal omegas - barriers and novel methods to narrow omega-3 gaps. A narrative review

Dietary intakes of omega-3 long chain polyunsaturated fatty acids (O3LC-PUFAs) such as eicosapentaenoic and docosahexaenoic acid are central to development and health across the life course. O3LC-PUFAs have been linked to neurological development, maternal and child health and the etiology of certain non-communicable diseases including age-related cognitive decline, cardiovascular disease, and diabetes. However, dietary inadequacies exist in the United Kingdom and on a wider global scale. One predominant dietary source of O3LC-PUFAs is fish and fish oils. However, growing concerns about overfishing, oceanic contaminants such as dioxins and microplastics and the trend towards plant-based diets appear to be acting as cumulative barriers to O3LC-PUFAs from these food sources. Microalgae are an alternative provider of O3LC-PUFA-rich oils. The delivery of these into food systems is gaining interest. The present narrative review aims to discuss the present barriers to obtaining suitable levels of O3LC-PUFAs for health and wellbeing. It then discusses potential ways forward focusing on innovative delivery methods to utilize O3LC-PUFA-rich oils including the use of fortification strategies, bioengineered plants, microencapsulation, and microalgae.

Prenatal iron supplementation adjusted to maternal iron stores reduces behavioural problems in 4-year-old children

Prenatal iron supplementation improves children's health and cognitive performance, but few studies explore behavioural development. This study assessed the effects of adjusting prenatal iron supplementation to maternal iron stores during early pregnancy on children's behavioural problems. Randomized controlled trial conducted in Tarragona (Spain) involving 230 nonanaemic pregnant women and their children after a 4-year follow-up. Based on haemoglobin (Hb) levels before gestational week (GW) 12, women receive different iron doses: those with Hb = 110-130 g/L were randomized to receive 80 or 40 mg/day and those with Hb > 130 g/L were randomized to receive 20 or 40 mg/day. Maternal iron stores at GW12 were classified using serum ferritin (SF) as low (SF < 15 µg/L), normal (SF = 15-65 µg/L), and normal-high (SF > 65 µg/L). Children's behaviour was assessed by parents using the Child Behaviour Checklist for ages 1.5-5 years and the Behaviour Rating Inventory of Executive Function-Preschool Version, and by teachers using the Teacher's Report Form for ages 1.5-5 years. Multivariable regression models were performed. Taking 80 mg/day of iron improved child behaviour when women had low iron stores but worsened it when mothers had normal-high iron stores, except for depressive and attention/hyperactivity problems. Taking 20 mg/day of iron improved behaviour only in those children whose mothers had SF > 65 µg/L in early pregnancy. Additionally, executive functioning improved at high doses of prenatal iron when maternal baseline SF < 15 µg/L. Adjusting prenatal iron supplementation to both maternal baseline Hb levels and iron stores reduces behavioural problems in 4-year-old children.

Importance of Maternal Iron Status on the Improvement of Cognitive Function in Children After Prenatal Iron Supplementation

INTRODUCTION

The effectiveness of prenatal iron supplementation improves maternal hematological outcomes, but little research has focused on child outcomes. The objective of this study was to assess whether prenatal iron supplementation adjusted to maternal needs improves children's cognitive functioning.

METHODS

The analyses included a subsample of nonanemic pregnant women recruited in early pregnancy and their children aged 4 years (n=295). Data were collected between 2013 and 2017 in Tarragona (Spain). On the basis of hemoglobin levels before the 12th gestational week, women receive different iron doses: 80 vs 40 mg/d if hemoglobin is 110-130 g/L and 20 vs 40 mg/d if hemoglobin >130 g/L. Children's cognitive functioning was assessed using the Wechsler Preschool and Primary Scale of Intelligence-IV and Developmental Neuropsychological Assessment-II tests. The analyses were carried out in 2022 after the completion of the study. Multivariate regression models were performed for assessing the association between different doses of prenatal iron supplementation and children's cognitive functioning.

RESULTS

Taking 80 mg/d of iron was positively associated with all the scales of the Wechsler Preschool and Primary Scale of Intelligence-IV and Neuropsychological Assessment-II when mothers had initial serum ferritin <15 µg/L, but it was negatively associated with Verbal Comprehension Index, Working Memory Index, Processing Speed Index, and Vocabulary Acquisition Index from Wechsler Preschool and Primary Scale of Intelligence-IV and verbal fluency index from Neuropsychological Assessment-II when mothers showed initial serum ferritin >65 µg/L. In the other group, taking 20 mg/d of iron was positively associated with Working Memory Index, Intelligence Quotient, verbal fluency, and emotion recognition indices when women had initial serum ferritin >65 µg/L.

CONCLUSIONS

Prenatal iron supplementation adjusted to the maternal hemoglobin levels and baseline iron stores improves cognitive functioning in children aged 4 years.

Evidence or no evidence for essential fatty acids in the treatment of autism spectrum disorders?

Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders that affect social communication, behavior, and sensory processing, in which PUFAs are considered important. This mini-review article aims to investigate the current evidence regarding the use of essential fatty acids (EFAs) in the treatment of autism spectrum disorders (ASDs). The study examines various research studies, related to EFAs, their benefits, and their role in ASD treatment. The article focuses on exploring the potential mechanisms underlying the effects of EFAs on ASDs, including their anti-inflammatory, antioxidant, and neuroprotective properties. Furthermore, the study discusses limitations and challenges associated with the use of EFAs in ASD treatment, including variability in dosage and duration of treatment. The results of this review indicate that while some studies suggest a positive effect of EFAs on ASD symptoms, there is currently insufficient evidence to support their routine use as a stand-alone treatment for ASD. The need for further research to better understand the potential benefits and limitations of EFAs in ASD treatment is highlighted.

Placental AA/EPA Ratio Is Associated with Obesity Risk Parameters in the Offspring at 6 Years of Age

During pregnancy, maternal polyunsaturated fatty acids (PUFA) are transferred to the fetus through the placenta by specific FA transporters (FATP). A higher perinatal exposure to n-6 over n-3 PUFA could be linked to excess fat mass and obesity development later in life. In this context, we aimed to assess the associations between long chain PUFAs (LC-PUFAs) (n-6, n-3, and n-6/n-3 ratios) measured in the placenta at term birth with obesity-related parameters in the offspring at 6 years of age and assess whether these associations are dependent on the placental relative expression of fatty acid transporters. As results, the PUFAn-6/PUFAn-3 ratio was 4/1, which scaled up to 15/1 when considering only the arachidonic acid/eicosapentaenoic acid ratio (AA/EPA ratio). Positive associations between the AA/EPA ratio and offspring's obesity risk parameters were found with weight-SDS, BMI-SDS, percent fat mass-SDS, visceral fat, and HOMA-IR (r from 0.204 to 0.375; all p < 0.05). These associations were more noticeable in those subjects with higher expression of fatty acid transporters. Therefore, in conclusion, a higher placental AA/EPA ratio is positively associated with offspring's visceral adiposity and obesity risk parameters, which become more apparent in subjects with higher expressions of placental FATPs. Our results support the potential role of n-6 and n-3 LC-PUFA in the fetal programming of obesity risk in childhood. For the present study, 113 healthy pregnant women were recruited during the first trimester of pregnancy and their offspring were followed up at 6 years of age. The fatty acid profiles and the expression of fatty acid transporters (FATP1 and FATP4) were analyzed from placental samples at birth. Associations between LC-PUFA (n-6, n-3, and n-6/n-3 ratios) and obesity risk parameters (weight, body mass index (BMI), percent fat mass, visceral fat, and homeostatic model assessment of insulin resistance (HOMA-IR)) in the offspring at 6 years of age were examined.

The Impact of Linoleic Acid on Infant Health in the Absence or Presence of DHA in Infant Formulas

Both linoleic acid (LA) and α-linolenic acid (ALA) are essential dietary fatty acids, and a balanced dietary supply of these is of the utmost importance for health. In many countries across the globe, the LA level and LA/ALA ratio in breast milk (BM) are high. For infant formula (IF), the maximum LA level set by authorities (e.g., Codex or China) is 1400 mg LA/100 kcal ≈ 28% of total fatty acid (FA) ≈ 12.6% of energy. The aims of this study are: (1) to provide an overview of polyunsaturated fatty acid (PUFA) levels in BM across the world, and (2) to determine the health impact of different LA levels and LA/ALA ratios in IF by reviewing the published literature in the context of the current regulatory framework. The lipid composition of BM from mothers living in 31 different countries was determined based on a literature review. This review also includes data from infant studies (intervention/cohort) on nutritional needs regarding LA and ALA, safety, and biological effects. The impact of various LA/ALA ratios in IF on DHA status was assessed within the context of the current worldwide regulatory framework including China and the EU. Country averages of LA and ALA in BM range from 8.5-26.9% FA and 0.3-2.65% FA, respectively. The average BM LA level across the world, including mainland China, is below the maximum 28% FA, and no toxicological or long-term safety data are available on LA levels > 28% FA. Although recommended IF LA/ALA ratios range from 5:1 to 15:1, ratios closer to 5:1 seem to promote a higher endogenous synthesis of DHA. However, even those infants fed IF with more optimal LA/ALA ratios do not reach the DHA levels observed in breastfed infants, and the levels of DHA present are not sufficient to have positive effects on vision. Current evidence suggests that there is no benefit to going beyond the maximum LA level of 28% FA in IF. To achieve the DHA levels found in BM, the addition of DHA to IF is necessary, which is in line with regulations in China and the EU. Virtually all intervention studies investigating LA levels and safety were conducted in Western countries in the absence of added DHA. Therefore, well-designed intervention trials in infants across the globe are required to obtain clarity about optimal and safe levels of LA and LA/ALA ratios in IF.

Oxidized linoleic acid metabolites regulate neuronal morphogenesis in vitro

Linoleic acid (LA, 18:2n-6) is an essential nutrient for optimal infant growth and brain development. The effects of LA in the brain are thought to be mediated by oxygenated metabolites of LA known as oxidized LA metabolites (OXLAMs), but evidence is lacking to directly support this hypothesis. This study investigated whether OXLAMs modulate key neurodevelopmental processes including axon outgrowth, dendritic arborization, cell viability and synaptic connectivity. Primary cortical neuron-glia co-cultures from postnatal day 0-1 male and female rats were exposed for 48h to the following OXLAMs: 1) 13-hydroxyoctadecadienoic acid (13-HODE); 2) 9-hydroxyoctadecadienoic acid (9-HODE); 3) 9,10-dihydroxyoctadecenoic acid (9,10-DiHOME); 4) 12(13)-epoxyoctadecenoic acid (12(13)-EpOME); 5) 9,10,13-trihydroxyoctadecenoic acid (9,10,13-TriHOME); 6) 9-oxo-octadecadienoic acid (9-OxoODE); and 7) 12,13-dihydroxyoctadecenoic acid (12,13-DiHOME). Axonal outgrowth, evaluated by Tau-1 immunostaining, was increased by 9-HODE, but decreased by 12,13-DiHOME in male but not female neurons. Dendrite arborization, evaluated by MAP2B-eGFP expression, was affected by 9-HODE, 9-OxoODE, and 12(13)-EpOME in male neurons and, by 12(13)-EpOME in female neurons. Neither cell viability nor synaptic connectivity were significantly altered by OXLAMs. Overall, this study shows select OXLAMs modulate neuron morphology in a sex-dependent manner, with male neurons being more susceptible.

Foraging on anthropogenic food predicts problem-solving skills in a seabird

Species and populations with greater cognitive performance are more successful at adapting to changing habitats. Accordingly, urban species and populations often outperform their rural counterparts on problem-solving tests. Paradoxically, urban foraging also might be detrimental to the development and integrity of animals' brains because anthropogenic foods often lack essential nutrients such as the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are important for cognitive performance in mammals and possibly birds. We tested whether urbanization or consumption of EPA and DHA are associated with problem-solving abilities in ring-billed gulls, a seabird that historically exploited marine environments rich in omega-3 fatty acids but now also thrives in urban centres. Using incubating adults nesting across a range of rural to urban colonies with equal access to the ocean, we tested whether urban gulls preferentially consumed anthropogenic food while rural nesters relied on marine organisms. As we expected individual variation in foraging habits within nesting location, we characterized each captured gulls' diet using stable isotope and fatty acid analyses of their red blood cells. To test their problem-solving abilities, we presented the sampled birds with a horizontal rendition of the string-pull test, a foraging puzzle often used in animal cognitive studies. The isotopic and fatty acid profiles of urban nesters indicated a diet comprising primarily anthropogenic food, whereas the profiles of rural nesters indicated a high reliance on marine organisms. Despite the gulls' degree of access to urban foraging habitat not predicting solving success, birds with biochemical profiles reflecting anthropogenic food (less DHA and a higher carbon-13 ratio in their red blood cells) had a greater probability of solving the string-pull test. These results suggest that experience foraging on anthropogenic food is the main explanatory factor leading to successful problem-solving, while regular consumption of omega-3s during incubation appears inconsequential.

The role of nutrients in human neurodevelopment and their potential to prevent neurodevelopmental adversity

Nutritional deficits or excesses affect a huge proportion of pregnant women worldwide. Maternal nutrition has a significant influence on the fetal environment and can dramatically impact fetal brain development. This paper reviews current nutritional supplements that can be used to optimise fetal neurodevelopment and prevent neurodevelopmental morbidities, including folate, iodine, vitamin B12, iron, and vitamin D. Interestingly, while correcting nutritional deficits can prevent neurodevelopmental adversity, overcorrecting them can in some cases be detrimental, so care needs to be taken when recommending supplementation in pregnancy. The potential benefits of using nutrition to prevent neurodiversity is shown by promising nutraceuticals, sulforaphane and creatine, both currently under investigation. They have the potential to promote improved neurodevelopmental outcomes through mitigation of pathological processes, including hypoxia, inflammation, and oxidative stress. Neurodevelopment is a complex process and whilst the role of micronutrients and macronutrients on the developing fetal brain is not completely understood, this review highlights the key findings thus far.

Adapting prenatal iron supplementation to maternal needs results in optimal child neurodevelopment: a follow-up of the ECLIPSES Study

Background

Prenatal prescription of standard iron supplements to prevent iron deficiency appears not to be appropriate for all women and their children, as some women may be at risk of iron deficiency and others at risk of iron excess early in pregnancy. The present study aimed to assess whether prenatal iron supplementation adapted to the needs of each pregnant woman affects their child’s neurodevelopment.

Methods

Follow-up of a community-based RCT involving 503 mother–child pairs. Non-anaemic pregnant women recruited in Tarragona (Spain) early in pregnancy were prescribed a daily iron dose based on their initial haemoglobin levels: Stratum 1 (Hb = 110–130 g/L, 80 or 40 mg/d of iron) and Stratum 2 (Hb > 130 g/L, 40 or 20 mg/d of iron). Women receiving 40 mg/d were considered the control group in each Strata. The child’s neurodevelopment was assessed at 40 days of age using the Bayley Scales of Infant Development-III (BSID-III). Adjusted multiple regression models were used.

Results

Multiple regression analyses showed no association between the intervention and control group within each Strata on the BSID-III scores on any of the developmental scales in children, including cognitive, language, and motor development: Stratum 1 (β 1.46, 95%CI -2.15, 5.07; β 1.30, 95%CI -1.99, 4.59; and β 2.04, 95%CI -3.88, 7.96, respectively) and Stratum 2 (β -4.04, 95%CI -7.27, 0.80; β -0.36, 95%CI -3.47, 2.75; and β -3.76, 95%CI -9.30, 1.78, respectively).

Conclusions

In non-anaemic women in early pregnancy, no differences were found in the cognitive, language and motor development of children at 40 days of age between the dose of iron tested in each case –adjusted to initial Hb levels– compared to the dose of the control group. Further studies are guaranteed to confirm our findings.

Trial registration

The ECLIPSES study was registered at www.clinicaltrialsregister.eu as EudraCT number 2012–005,480-28.

Are Brain and Cognitive Reserve Shaped by Early Life Circumstances?

When growing older, many people are faced with cognitive deterioration, which may even amount to a form of dementia at some point in time. Although neuropathological signs of dementia disorders can often be demonstrated in brains of patients, the degree to which clinical symptoms are present does mostly not accurately reflect the amount of neuropathology that is present. Sometimes existent pathology even goes without any obvious clinical presentation. An explanation for this phenomenon may be found in the concept of reserve capacity. Reserve capacity refers to the ability of the brain to effectively buffer changes that are associated with normal aging processes and to cope with pathological damage. A larger reserve capacity has been suggested to increase resilience against age-associated cognitive deterioration and dementia disorders. Traditionally, a division has been made between brain reserve, which is based on morphological characteristics of the brain, and cognitive reserve, which is based on functional characteristics of the brain. The present review discusses the premises that brain and cognitive reserve capacity are shaped by prenatal and early postnatal factors. Evidence is accumulating that circumstances during the first 1,000 days of life are of the utmost importance for the lifelong health of an individual. Cognitive deterioration and dementia disorders may also have their origin in early life and a potentially important pathway by which the early environment affects the risk for neurodegenerative diseases is by developmental programming of the reserve capacity of the brain. The basic idea behind developmental programming of brain and cognitive reserve is explained and an overview of studies that support this idea is presented. The review is concluded by a discussion of potential mechanisms, synthesis of the evidence and relevance and future directions in the field of developmental origins of reserve capacity.

Susceptibility of Female Mice to the Dietary Omega-3/Omega-6 Fatty-Acid Ratio: Effects on Adult Hippocampal Neurogenesis and Glia

Maternal intake of omega-3 (n-3 PUFAs) and omega-6 (n-6 PUFAs) polyunsaturated fatty acids impacts hippocampal neurogenesis during development, an effect that may extend to adulthood by altering adult hippocampal neurogenesis (AHN). The n-3 PUFAs and n-6 PUFAs are precursors of inflammatory regulators that potentially affect AHN and glia. Additionally, n-3 PUFA dietary supplementation may present a sexually dimorphic action in the brain. Therefore, we postulated that dietary n-6/n-3 PUFA balance shapes the adult DG in a sex-dependent manner influencing AHN and glia. We test our hypothesis by feeding adult female and male mice with n-3 PUFA balanced or deficient diets. To analyze the immunomodulatory potential of the diets, we injected mice with the bacterial endotoxin lipopolysaccharide (LPS). LPS reduced neuroblast number, and its effect was exacerbated by the n-3 PUFA-deficient diet. The n-3 PUFA-deficient diet reduced the DG volume, AHN, microglia number, and surveilled volume. The diet effect on most mature neuroblasts was exclusively significant in female mice. Colocalization and multivariate analysis revealed an association between microglia and AHN, as well as the sexual dimorphic effect of diet. Our study reveals that female mice are more susceptible than males to the effect of dietary n-6/n-3 PUFA ratio on AHN and microglia.

INTERESTERIFIED FAT MATERNAL CONSUMPTION BEFORE CONCEPTION PROGRAMMS MEMORY AND LEARNING OF ADULTHOOD OFFSPRING: how big is this deleterious repercussion?

In recent years, interesterified fat (IF) has largely replaced trans fat in industrialized food. Studies of our research group showed that IF consumption may not be safe for central nervous system (CNS) functions. Our current aim was to evaluate IF maternal consumption before conception on cognitive performance of adult rat offspring. Female Wistar rats were fed with standard chow plus 20% soybean and fish oil mix (control group) or plus 20% IF from weaning until adulthood (before mating), when the diets were replaced by standard chow only. Following the gestation and pups' development, locomotion and memory performance followed by neurotrophin immunocontent and fatty acids (FA) profile in the hippocampus of the adulthood male offspring were quantified. Maternal IF consumption before conception decreased hippocampal palmitoleic acid incorporation, proBDNF and BDNF levels, decreasing both exploratory activity and memory performance in adult offspring. Considering that, the adult male offspring did not consume IF directly, further studies are needed to understand the molecular mechanisms and if the IF maternal preconception consumption could induce the epigenetic changes observed here. Our outcomes reinforce an immediate necessity to monitor and / or question the replacement of trans fat by IF with further studies involving CNS functions.

Serum cytokines are associated with n-3 polyunsaturated fatty acids and not with methylmercury measured in infant cord blood in the Seychelles child development study

BACKGROUND

Maternal fish consumption increases infant methylmercury (MeHg) exposure and polyunsaturated fatty acid (PUFA) concentrations. The n-3 PUFA are regulators of inflammation while MeHg may impact the cord cytokine profile and, subsequently, contribute to immune mediated outcomes. This study aimed to investigate associations between infant MeHg exposure and cord cytokine concentrations while adjusting for cord PUFA.

METHODS

We studied participants in the Seychelles Child Development Study (SCDS) Nutrition Cohort 2 (NC2), a large birth cohort in a high fish-eating population. Whole blood MeHg, serum PUFA and serum cytokine concentrations (IFN-γ, IL-1β, IL-2, IL-12p70, TNF-α, IL-4, IL-10, IL-13, IL-6 and IL-8) were measured in cord blood collected at delivery (n = 878). Linear regression examined associations between infant MeHg exposure and cord cytokines concentrations, with and without adjustment for cord PUFA. An interaction model examined cord MeHg, cytokines and tertiles of the n-6:n-3 ratio (low/medium/high).

RESULTS

There was no overall association between cord MeHg (34.08 ± 19.98 μg/L) and cytokine concentrations, with or without adjustment for PUFA. Increased total n-3 PUFA (DHA, EPA and ALA) was significantly associated with lower IL-10 (β = -0.667; p = 0.007) and lower total Th2 (IL-4, IL-10 and IL-13) (β = -0.715; p = 0.036). In the interaction model, MeHg and IL-1β was positive and significantly different from zero in the lowest n-6:n-3 ratio tertile (β = 0.002, p = 0.03).

CONCLUSION

Methylmercury exposure from fish consumption does not appear to impact markers of inflammation in cord blood. The association of cord n-3 PUFA with lower IL-10 and total Th2 cytokines suggests that they may have a beneficial influence on the regulation of the inflammatory milieu. These findings are important for public health advice and deserve to be investigated in follow up studies.

Maternal C-Peptide and Insulin Sensitivity, but Not BMI, Associate with Fatty Acids in the First Trimester of Pregnancy

Maternal obesity in pregnancy is a pro-inflammatory condition exposing the fetus to an adverse environment. Here, we tested associations of maternal obesity (primary exposures: BMI, leptin) and metabolic parameters (secondary exposures: glucose, C-peptide, and insulin sensitivity) with total serum concentrations of fatty acids in the first trimester of human pregnancy. This cross-sectional study included 123 non-smoking women with singleton pregnancy. In maternal serum, cotinine, leptin, and C-peptide (ELISA), glucose (hexokinase-based test) and fatty acids (gas chromatography) were quantified, and the insulin sensitivity index (ISHOMA) was calculated. Concentrations of fatty acid classes and total fatty acids did not differ between BMI or leptin categories. However, n-3 polyunsaturated fatty acids (PUFA) were decreased in the category with the highest C-peptide concentration (n-3 PUFA: CI -35.82--6.28, p < 0.006) and in the lowest ISHOMA category (n-3 PUFA: CI -36.48--5.61, p < 0.008). In a subcohort, in which fetal sex was determined (RT-qPCR of placental tissue), C-peptide was significantly associated with docosahexaenoic acid (DHA) in mothers bearing a female (n = 46), but not male (n = 37) fetus. In conclusion, pregnant women with high fasting C-peptide and low ISHOMA had decreased n-3 PUFA, and DHA was lower with higher C-peptide only in mothers bearing a female fetus.

The Influence of Prenatal DHA Supplementation on Individual Domains of Behavioral Functioning in School-Aged Children: Follow-Up of a Randomized Controlled Trial

Docosahexaenoic acid (DHA) accumulates in the fetal brain during pregnancy and is thought to have a role in supporting neurodevelopment. We conducted a multicenter, double-blind, randomized controlled trial in women with a singleton pregnancy who were <21 weeks’ gestation at trial entry. Women were provided with 800 mg DHA/day or a placebo supplement from trial entry until birth. When children reached seven years of age, we invited parents to complete the Strengths and Difficulties Questionnaire (SDQ), the Behavior Rating Inventory of Executive Function (BRIEF), and the Conners 3rd Edition Attention-Deficit Hyperactivity Disorder (ADHD) Index to assess child behavior and behavioral manifestations of executive dysfunction. There were 543 parent–child pairs (85% of those eligible) that participated in the follow-up. Scores were worse in the DHA group than the placebo group for the BRIEF Global Executive, Behavioral Regulation and Metacognition Indexes, and the Shift, Inhibit, Monitor, Working Memory, and Organization of Materials scales, as well as for the Conners 3 ADHD index, and the SDQ Total Difficulties score, Hyperactivity/Inattention score, and Peer Relationship Problems score. In this healthy, largely term-born sample of children, prenatal DHA supplementation conferred no advantage to childhood behavior, and instead appeared to have an adverse effect on behavioral functioning, as assessed by standardized parental report scales.

Mental Health in Childhood and Adolescence: The Role of Polyunsaturated Fatty Acids

There is increasing awareness of the importance of polyunsaturated fatty acids (PUFAs) for optimal brain development and function. In recent decades, researchers have confirmed the central role of PUFAs in a variety of patho-physiological processes. These agents modulate the mechanisms of brain cell signalling including the dopaminergic and serotonergic pathways. Therefore, nutritional insufficiencies of PUFAs may have adverse effects on brain development and developmental outcomes. The role of n-3 PUFAs has been studied in several psychiatric disorders in adulthood: schizophrenia, major depression, bipolar disorder, anxiety disorders, obsessive-compulsive disorder, post-traumatic stress disorder, attention deficit hyperactivity disorder (ADHD), autism spectrum disorders, eating disorders, substance use disorder, and borderline personality disorder. In contrast to the great number of studies conducted in adults, there are only limited data on the effects of n-3 PUFA supplementation in children and adolescents who suffer from mental disorders or show a high risk of developing psychiatric disorders. The aim of this review is to provide a complete and updated account of the available evidence of the impact of polyunsaturated fatty acids on developmental psychopathology in children and adolescents and the effect of fatty acid supplementation during developmental milestones, particularly in high-risk populations of children with minimal but detectable signs or symptoms of mental disorders.