Dietary essential fatty acids and brain function: a developmental perspective on mechanisms

[Elucidation of the pathology of mental disorders focusing on polyunsaturated fatty acids and FABPs]

Polyunsaturated fatty acids (PUFAs) are essential for brain development and function, and an imbalance of brain PUFAs is linked to mental disorders like autism and schizophrenia. However, the cellular and molecular mechanisms underlying the effects of PUFAs on the brain remain largely unknown. Since they are insoluble in water, specific transporters like fatty acid binding proteins (FABPs), are required for transport and function of PUFAs within cells. We focused on the relationship between FABP-mediated homeostasis of brain PUFAs and neural plasticity. We found that FABP3, with a high affinity for n-6 PUFAs, is predominantly expressed in the GABAergic inhibitory interneurons of the anterior cingulate cortex (ACC) in the adult mouse brain. FABP3 knockout (KO) mice show increased GABA synthesis and inhibitory synaptic transmission in the ACC. We also found that FABP7 controls lipid raft function in astrocytes, and astrocytes lacking FABP7 exhibit changes in response to external stimuli. Furthermore, in FABP7 KO mice, dendritic protrusion formation in pyramidal neurons becomes abnormal, and we have reported a decrease in spine density and excitatory synaptic transmission. Here, we introduced recent advances in the understanding of the functions of PUFAs and FABPs in the brain, focusing especially on FABP3 and FABP7, in relation to human mental disorders.

Maternal concentrations of phthalates and Attention-Deficit Hyperactivity Disorder (ADHD-) related symptoms in children aged 2 to 4 years from Odense child cohort

BACKGROUND

Phthalates are endocrine disrupting chemicals used in everyday consumer products. Several epidemiological studies have examined the association between prenatal phthalate concentration and Attention-Deficit Hyperactivity Disorder (ADHD) in offspring, but the findings have been inconclusive.

OBJECTIVES

To investigate the association between maternal urinary concentrations of phthalate metabolites during pregnancy and ADHD related symptoms in children at 2 to 4 years in a large prospective cohort.

METHODS

In the Odense Child Cohort from Denmark were women recruited in early pregnancy from 2010 to 2012. Phthalate concentrations were measured in urine samples collected in 3rd trimester and separated into low and high weight phthalates. Parents filled in the Child Behavior Checklist for ages 1.5 to 5 years (CBCL/1½-5), including a 6-item ADHD symptom scale at children aged 2 to 4 years. Data were analysed by use of adjusted negative binomial regression.

RESULTS

A total of 658 mother-child pairs were included. Urinary phthalate metabolite concentrations were generally low compared to previous cohorts. A doubling in maternal concentration of the low-weighted phthalate metabolite MCPP was significantly associated with lower ADHD symptoms score in children (IRR: 0.95 (95 % CI 0.91-0.98)), strongest in girls (IRR: 0.92 (0.87-0.98)). Sex differences were observed. High maternal phthalate metabolite concentrations were associated with lower ADHD symptom score in girls, significant trends across tertile of MCPP and MnBP (p = 0.018, p = 0.038, respectively). In boys, maternal concentrations of high-molecular-weight phthalates (MBzP, ∑DiNP and ∑DEHP) were associated with an almost significantly higher ADHD symptom score (IRR for a doubling in concentration: 1.04 (95 % CI: 0.99-1.10), IRR: 1.05 (95 % CI: 0.97-1.13), IRR: 1.04 (95 % CI: 0.99-1.10), respectively).

CONCLUSION

Maternal concentration of the low-weighted phthalate metabolite MCPP was significantly associated with a lower ADHD symptom score in children, strongest in girls. Maternal concentrations of high-molecular-weight phthalates were associated with non-significant increase in ADHD symptom score in boys.

Brain Metabolomics in Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS)

The course of pathophysiological mechanisms involved in fragile X-associated tremor/ataxia syndrome (FXTAS) remains largely unknown. Previous proteomics and metabolomics studies conducted in blood samples collected from FMR1 premutation carriers with FXTAS reported abnormalities in energy metabolism, and precursors of gluconeogenesis showed significant changes in plasma expression levels in FMR1 premutation carriers who developed FXTAS. We conducted an analysis of postmortem human brain tissues from 44 donors, 25 brains with FXTAS, and 19 matched controls. We quantified the metabolite relative abundance in the inferior temporal gyrus and the cerebellum using untargeted mass spectrometry (MS)-based metabolomics. We investigated how the metabolite type and abundance relate to the number of cytosine-guanine-guanine (CGG) repeats, to markers of neurodegeneration, and to the symptoms of FXTAS. A metabolomic analysis identified 191 primary metabolites, the data were log-transformed and normalized prior to the analysis, and the relative abundance was compared between the groups. The changes in the relative abundance of a set of metabolites were region-specific with some overlapping results; 22 metabolites showed alterations in the inferior temporal gyrus, while 21 showed differences in the cerebellum. The relative abundance of cytidine was decreased in the inferior temporal gyrus, and a lower abundance was found in the cases with larger CGG expansions; oleamide was significantly decreased in the cerebellum. The abundance of 11 metabolites was influenced by changes in the CGG repeat number. A histological evaluation found an association between the presence of microhemorrhages in the inferior temporal gyrus and a lower abundance of 2,5-dihydroxypyrazine. Our study identified alterations in the metabolites involved in the oxidative-stress response and bioenergetics in the brains of individuals with FXTAS. Significant changes in the abundance of cytidine and oleamide suggest their potential as biomarkers and therapeutic targets for FXTAS.

Omega-3 fatty acids: Current insights into mechanisms of action in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is one of the autoimmune diseases characterized by the lack of self-tolerance and the formation of immune complexes and nuclear autoantigens resulting in inflammation in multiple organs. Nowadays, the major aim of SLE therapy is the control of disease activity. However, the biological heterogeneity between patients and the absence of safe and specific targeted treatments complicate the lupus management. Therefore, the potential prophylactic effects of natural therapy considering the potential side effects of classical pharmacology, also the role of diet therapy in decreasing co-morbidities and improving quality of life in SLE patients could be a promising approach to SLE disease. Omega-3 polyunsaturated fatty acids (omega-3 PUFAs) are one of the agents that are considered for their preventive and therapeutic properties in disease activity of SLE and the related complications. The intake of omega-3 PUFAs likely has a direct relationship with improvements in inflammatory, cardiovascular, depressive, and neuromotor symptoms of the patients. The current review summarizes clinical and preclinical studies with comprehensive insights into the mechanisms of action of omega-3 fatty acids (omega-3 FAs) in Systemic Lupus Erythematosus to provide an update on the negative and positive aspects of the intake of omega-3 FAs in SLE patients.

Paternal preconceptional diet enriched with n-3 polyunsaturated fatty acids affects offspring brain function in mice

Recent studies demonstrate that paternal nutrition prior to conception may determine offspring development and health through epigenetic modification. This study aims to investigate the effects of paternal supplementation of n-3 polyunsaturated fatty acids (n-3 PUFAs) on the brain development and function, and associated gene imprinting in the offspring. Three to four-week-old male C57BL/6J mice (founder) were fed with an n-3 PUFA-deficient diet (n-3 D), and two n-3 PUFA supplementation diets – a normal n-3 PUFA content diet (n-3 N) and a high n-3 PUFA content diet (n-3 H) for 12 weeks. Then they were mated to 10-week-old virgin female C57BL/6J mice to generate the offspring. The results showed that paternal n-3 PUFA supplementation in preconception reduced the anxiety- and depressive-like behavior, and improved sociability, learning and memory in the offspring, along with increased synaptic number, upregulated expressions of neuron specific enolase, myelin basic protein, glial fibrillary acidic protein, brain-derived neurotrophic factor in the hippocampus and cerebral cortex, and altered expressions of genes associated with mitochondria biogenesis, fusion, fission and autophagy. Furthermore, with paternal n-3 PUFA supplementation, the expression of imprinted gene Snrpn was downregulated both in testes of the founder mice and their offspring, but upregulated in the cerebral cortex and hippocampus, with altered DNA methylation in its differentially methylated region. The data suggest that higher paternal intake of n-3 PUFAs in preconception may help to maintain optimal brain development and function in the offspring, and further raise the possibility of paternal nutritional intervention for mental health issues in subsequent generations.

Alteration of Fatty Acid Profile in Fragile X Syndrome

Fragile X Syndrome (FXS) is the most prevalent monogenic cause of Autism Spectrum Disorders (ASDs). Despite a common genetic etiology, the affected individuals display heterogenous metabolic abnormalities including hypocholesterolemia. Although changes in the metabolism of fatty acids (FAs) have been reported in various neuropsychiatric disorders, it has not been explored in humans with FXS. In this study, we investigated the FA profiles of two different groups: (1) an Argentinian group, including FXS individuals and age- and sex-matched controls, and (2) a French-Canadian group, including FXS individuals and their age- and sex-matched controls. Since phospholipid FAs are an indicator of medium-term diet and endogenous metabolism, we quantified the FA profile in plasma phospholipids using gas chromatography. Our results showed significantly lower levels in various plasma FAs including saturated, monosaturated, ω-6 polyunsaturated, and ω-3 polyunsaturated FAs in FXS individuals compared to the controls. A decrease in the EPA/ALA (eicosapentaenoic acid/alpha linoleic acid) ratio and an increase in the DPA/EPA (docosapentaenoic acid/eicosapentaenoic acid) ratio suggest an alteration associated with desaturase and elongase activity, respectively. We conclude that FXS individuals present an abnormal profile of FAs, specifically FAs belonging to the ω-3 family, that might open new avenues of treatment to improve core symptoms of the disorder.

Genetic Variants in One-Carbon Metabolism and Their Effects on DHA Biomarkers in Pregnant Women: A Post-Hoc Analysis

The delivery of docosahexanoic acid (DHA) to the fetus is dependent on maternal one-carbon metabolism, as the latter supports the hepatic synthesis and export of a DHA-enriched phosphatidylcholine molecule via the phosphatidylethanolamine N-methyltransferase (PEMT) pathway. The following is a post-hoc analysis of a choline intervention study that sought to investigate whether common variants in one-carbon metabolizing genes associate with maternal and/or fetal blood biomarkers of DHA status. Pregnant women entering their second trimester were randomized to consume, until delivery, either 25 (n = 15) or 550 (n = 15) mg choline/d, and the effects of genetic variants in the PEMT, BHMT, MTHFD1, and MTHFR genes on DHA status were examined. Variant (vs. non-variant) maternal PEMT rs4646343 genotypes tended to have lower maternal RBC DHA (% total fatty acids) throughout gestation (6.9% vs. 7.4%; main effect, p = 0.08) and lower cord RBC DHA at delivery (7.6% vs. 8.4%; main effect, p = 0.09). Conversely, variant (vs. non-variant) maternal MTHFD1 rs2235226 genotypes exhibited higher cord RBC DHA (8.3% vs. 7.3%; main effect, p = 0.0003) and higher cord plasma DHA (55 vs. 41 μg/mL; main effect, p = 0.05). Genotype tended to interact with maternal choline intake (p < 0.1) to influence newborn DHA status for PEMT rs4646343 and PEMT rs7946. These data support the need to consider variants in one-carbon metabolic genes in studies assessing DHA status and requirements during pregnancy.

Effects of mono- and di-glycerides/phospholipids (MDG/PL) on the bioaccessibility of lipophilic nutrients in a protein-based emulsion system

Lipophilic nutrients are known to have relatively poor absorption, thus limiting their bioaccessibility. Consequently, researchers in food and pharmaceutical areas are exploring different techniques to promote the efficient delivery of lipophilic nutrients. The effects of two polar lipids, namely mono-, di-glycerides (MDG) and lecithin (PL), on the bioaccessibility of lipophilic nutrients were investigated in this study with a protein-based emulsion model system. During the emulsion preparation and formation, the incorporation of MDG/PL was found to benefit the dissolution and stabilization of lipophilic nutrients, such as lutein, and could also modify the construction of the emulsion surface. An in vitro digestion study showed that the use of MDG/PL could significantly increase the bioaccessibility of lipophilic nutrients [lutein, vitamin E, and docosahexaenoic acid (DHA)] by 13.52%, 186.90%, and 36.17% in a protein-based emulsion system. The use of MDG and PL decreased the interfacial tension in all the samples: protein only 20.65 mN m^-1, protein-PL 6.47 mN m^-1, and protein-MDG/PL 4.23 mN m^-1, as well as 12.11 mN m^-1, 1.26 mN m^-1 and 1.16 mN m^-1 with the presence of bile salts. Caco-2 cell culture results showed that, with the application of MDG/PL, the absorption rate of micelles was higher than that in the other groups and this resulted in a 70% absorption increase for lutein. Therefore, MDG/PL can improve the lipophilic nutrient absorption via promoting the affinity of formed micelles to the enterocytes of the small intestine. This study exhibited the effectiveness of MDG/PL on improving the bioaccessibility of lipophilic nutrients in a protein-based emulsion system mimicking the digestion and absorption fate of breast milk in an infant's gastric intestinal tract, thus suggesting that MDG/PL can be used as a technical pathway to improve the absorption of lipophilic nutrients.

Nutrition, nutritional deficiencies, and schizophrenia: An association worthy of constant reassessment

Schizophrenia is a mental health disorder that occurs worldwide, cutting across cultures, socioeconomic groups, and geographical barriers. Understanding the details of the neurochemical basis of schizophrenia, factors that contribute to it and possible measures for intervention are areas of ongoing research. However, what has become more evident is the fact that in targeting the neurochemical imbalances that may underlie schizophrenia, the type of response seen with currently available phamacotherapeutic agents does not provide all the answers that are needed. Therefore, the possible contribution of non-pharmacological approaches to schizophrenia management is worthy of consideration. In recent times, research is beginning to show nutrition may play a possibly significant role in schizophrenia, affecting its development, progression and management; however, while attempts had been made to examine this possible relationship from different angles, articles addressing it from a holistic point of view are not common. In this review, we examine existing scientific literature dealing with the possible relationship between nutrition and schizophrenia, with a view to elucidating the impact of diet, nutritional deficiencies and excesses on the aetiology, progression, management and outcome of schizophrenia. Secondly, the effect of nutritional supplements in prevention, as sole therapy, or adjuncts in schizophrenia management are examined.

Placental 13C-DHA metabolism and relationship with maternal BMI, glycemia and birthweight

BACKGROUND

Fetal docosahexaenoic acid (DHA) supply relies on preferential transplacental transfer, which is regulated by placental DHA lipid metabolism. Maternal hyperglycemia and obesity associate with higher birthweight and fetal DHA insufficiency but the role of placental DHA metabolism is unclear.

METHODS

Explants from 17 term placenta were incubated with 13C-labeled DHA for 48 h, at 5 or 10 mmol/L glucose treatment, and the production of 17 individual newly synthesized 13C-DHA labeled lipids quantified by liquid chromatography mass spectrometry.

RESULTS

Maternal BMI positively associated with 13C-DHA-labeled diacylglycerols, triacylglycerols, lysophospholipids, phosphatidylcholine and phosphatidylethanolamine plasmalogens, while maternal fasting glycemia positively associated with five 13C-DHA triacylglycerols. In turn, 13C-DHA-labeled phospholipids and triacylglycerols positively associated with birthweight centile. In-vitro glucose treatment increased most 13C-DHA-lipids, but decreased 13C-DHA phosphatidylethanolamine plasmalogens. However, with increasing maternal BMI, the magnitude of the glucose treatment induced increase in 13C-DHA phosphatidylcholine and 13C-DHA lysophospholipids was curtailed, with further decline in 13C-DHA phosphatidylethanolamine plasmalogens. Conversely, with increasing birthweight centile glucose treatment induced increases in 13C-DHA triacylglycerols were exaggerated, while glucose treatment induced decreases in 13C-DHA phosphatidylethanolamine plasmalogens were diminished.

CONCLUSIONS

Maternal BMI and glycemia increased the production of different placental DHA lipids implying impact on different metabolic pathways. Glucose-induced elevation in placental DHA metabolism is moderated with higher maternal BMI. In turn, findings of associations between many DHA lipids with birthweight suggest that BMI and glycemia promote fetal growth partly through changes in placental DHA metabolism.

Early life stress exposure associated with reduced polyunsaturated-containing lipids in low-income children

BACKGROUND

Psychosocial stress in early childhood is associated with adult obesity and cardiometabolic disease. The association of psychosocial stress with the metabolome in childhood is unknown.

METHOD

Low-income children (n = 28, mean age 1.8 years), recruited from the community, participated. Psychosocial stress was measured by diurnal salivary cortisol (cortisol intercept and slope) and by mother-reported chaos in the home using the Confusion, Hubbub, and Order Scale (CHAOS). At mean age 6.1 years, anthropometry was collected and fasting metabolites measured using an untargeted metabolomics and shotgun lipidomics platform.

RESULTS

Cortisol slope was inversely associated with fatty acid (FA) 20:3, FA 20:4 and polyunsaturated fatty acids (PUFA) metabolites. A higher CHAOS score was associated with lower very long-chain PUFA metabolites and a trend towards lower long-chain PUFA containing triglycerides.

CONCLUSIONS

Psychosocial stress in early childhood, measured with both biological markers and parent report, was associated with lower PUFAs later in childhood. Future work should examine potential mechanisms of association, including dietary intake or direct effects on polyunsaturated fatty acid levels or metabolism.

IMPACT

In this longitudinal study, the key message is that diurnal cortisol patterns and greater parent-reported psychosocial stress exposure in early childhood are associated with lower plasma polyunsaturated fatty acid containing lipids 5 years later, potentially indicating altered dietary intake or metabolism associated with psychosocial stress. Untargeted metabolomics and lipidomics can be used to assess changes in metabolism response to psychosocial stress. Stress exposure in early childhood may be associated with the future metabolome. Future work should examine potential pathways of association, including dietary intake and direct effects on metabolism.

Problem Solving in Animals: Proposal for an Ontogenetic Perspective

Simple Summary

Animals must be able to solve problems to access food and avoid predators. Problem solving is not a complicated process, often relying only on animals exploring their surroundings, and being able to learn and remember information. However, not all species, populations, or even individuals, can solve problems, or can solve problems in the same way. Differences in problem-solving ability could be due to differences in how animals develop and grow, including differences in their genetics, hormones, age, and/or environmental conditions. Here, we consider how an animal’s problem-solving ability could be impacted by its development, and what future work needs to be done to understand the development of problem solving. We argue that, considering how many different factors are involved, focusing on individual animals, and individual variation, is the best way to study the development of problem solving.

Abstract

Problem solving, the act of overcoming an obstacle to obtain an incentive, has been studied in a wide variety of taxa, and is often based on simple strategies such as trial-and-error learning, instead of higher-order cognitive processes, such as insight. There are large variations in problem solving abilities between species, populations and individuals, and this variation could arise due to differences in development, and other intrinsic (genetic, neuroendocrine and aging) and extrinsic (environmental) factors. However, experimental studies investigating the ontogeny of problem solving are lacking. Here, we provide a comprehensive review of problem solving from an ontogenetic perspective. The focus is to highlight aspects of problem solving that have been overlooked in the current literature, and highlight why developmental influences of problem-solving ability are particularly important avenues for future investigation. We argue that the ultimate outcome of solving a problem is underpinned by interacting cognitive, physiological and behavioural components, all of which are affected by ontogenetic factors. We emphasise that, due to the large number of confounding ontogenetic influences, an individual-centric approach is important for a full understanding of the development of problem solving.

Possible involvement of fatty acid binding proteins in psychiatric disorders

Polyunsaturated fatty acids (PUFAs) are essential for brain development and function. Increasing evidence has shown that an imbalance of PUFAs is associated with various human psychiatric disorders, including autism and schizophrenia. However, the mechanisms underlying the effects of PUFAs on brain functions at cellular and molecular levels remain unclear. Since PUFAs are insoluble in water, specific transporters are required to deliver PUFAs to appropriate intracellular compartments. Fatty acid-binding proteins (FABPs), the cellular chaperones of PUFAs, are involved in PUFA intracellular trafficking, signal transduction, and gene transcription. Therefore, we focused on the relationship between FABP-regulated PUFA homeostasis in the brain and neuronal plasticity. The authors previously reported that FABP3, which preferentially binds to n-6 PUFAs, is strongly expressed in the gamma-aminobutyric acid (GABAergic) inhibitory interneurons of the adult mouse anterior cingulate cortex (ACC), which is a component of the limbic cortex and is important for the coordination of cognitive and emotional behaviors. Interestingly, Fabp3 KO mice show increased GABA synthesis and abnormal excitatory/inhibitory balance in the ACC. In addition, studies have indicated that FABP7, which preferentially binds to n-3 PUFAs, controls lipid raft function in astrocytes, and astrocytic Fabp7 deficiency results in an altered response of astrocytes to external stimuli. Furthermore, Fabp7 KO mice exhibit aberrant dendritic morphology, and decreased spine density and excitatory synaptic transmission in pyramidal neurons. This review summarizes relationship between PUFAs or FABPs and human psychiatric disorders and discusses recent progress in elucidating the function of FABPs, especially FABP3 and 7, in the brain.

Role of ferroptosis in neurological diseases

Ferroptosis is a newly identified form of nonapoptotic regulated cell death (RCD) characterized by iron-dependent accumulation of lipid peroxides which leads to oxidative stress and cell death. Recent studies have indicated that ferroptosis plays an essential role in the pathology of neurological diseases, such as intracerebral hemorrhage, ischemic stroke, epilepsy, neurodegenerative diseases, traumatic brain injury and brain cancer. This review focuses on the latest researches on the relationship of ferroptosis with nervous system diseases, highlighting the ferroptosis-based mechanisms, and elaborating the new perspective therapeutic targets of neurological disorders.

Structured form of DHA prevents neurodegenerative disorders: A better insight into the pathophysiology and the mechanism of DHA transport to the brain

Docosahexaenoic acid (DHA) is one of the most important fatty acids that plays a critical role in maintaining proper brain function and cognitive development. Deficiency of DHA leads to several neurodegenerative disorders and, therefore, dietary supplementations of these fatty acids are essential to maintain cognitive health. However, the complete picture of how DHA is incorporated into the brain is yet to be explored. In general, the de novo synthesis of DHA is poor, and targeting the brain with specific phospholipid carriers provides novel insights into the process of reduction of disease progression. Recent studies have suggested that compared to triacylglycerol form of DHA, esterified form of DHA (i.e., lysophosphatidylcholine [lysoPC]) is better incorporated into the brain. Free DHA is transported across the outer membrane leaflet of the blood-brain barrier via APOE4 receptors, whereas DHA-lysoPC is transported across the inner membrane leaflet of the blood-brain barrier via a specific protein called Mfsd2a. Dietary supplementation of this lysoPC specific form of DHA is a novel therapy and is used to decrease the risk of various neurodegenerative disorders. Currently, structured glycerides of DHA - novel nutraceutical agents - are being widely used for the prevention and treatment of various neurological diseases. However, it is important to fully understand their metabolic regulation and mechanism of transportation to the brain. This article comprehensively reviews various studies that have evaluated the bioavailability of DHA, mechanisms of DHA transport, and role of DHA in preventing neurodegenerative disorders, which provides better insight into the pathophysiology of these disorders and use of structured DHA in improving neurological health.

Exploring the role of LC-PUFA metabolism in pregnancy complications

Maternal nutrition during pregnancy plays a significant role in growth and development of the placenta and influencing pregnancy outcome. Suboptimal nutritional status during early gestational period compromises the normal course of pregnancy leading to adverse maternal and fetal outcomes. Omega-3 and omega-6 long chain polyunsaturated fatty acids (LC-PUFA) are important for the growth and development of the placenta. Maternal fatty acids and their metabolites influence the normal course of pregnancy by regulating cell growth and development, cell signaling, regulate angiogenesis, modulate inflammatory responses and influence various structural and functional processes. Alterations in LC-PUFA and their metabolites may result in inadequate spiral artery remodeling or placental angiogenesis leading to structural and functional deficiency of the placenta which contributes to several pregnancy complications like preeclampsia, gestational diabetes mellitus, intrauterine growth restriction, and results in adverse birth outcomes. In this review, we summarize studies examining the role of fatty acids and their metabolites in pregnancy. We also discuss the possible molecular mechanisms through which LC-PUFA influences placental growth and development. Studies have demonstrated that omega-3 fatty acid supplementation lowers the incidence of preterm births, but its effect on reducing pregnancy complications are inconclusive.

Essential omega-3 fatty acids tune microglial phagocytosis of synaptic elements in the mouse developing brain

Omega-3 fatty acids (n-3 PUFAs) are essential for the functional maturation of the brain. Westernization of dietary habits in both developed and developing countries is accompanied by a progressive reduction in dietary intake of n-3 PUFAs. Low maternal intake of n-3 PUFAs has been linked to neurodevelopmental diseases in Humans. However, the n-3 PUFAs deficiency-mediated mechanisms affecting the development of the central nervous system are poorly understood. Active microglial engulfment of synapses regulates brain development. Impaired synaptic pruning is associated with several neurodevelopmental disorders. Here, we identify a molecular mechanism for detrimental effects of low maternal n-3 PUFA intake on hippocampal development in mice. Our results show that maternal dietary n-3 PUFA deficiency increases microglia-mediated phagocytosis of synaptic elements in the rodent developing hippocampus, partly through the activation of 12/15-lipoxygenase (LOX)/12-HETE signaling, altering neuronal morphology and affecting cognitive performance of the offspring. These findings provide a mechanistic insight into neurodevelopmental defects caused by maternal n-3 PUFAs dietary deficiency.

Prenatal and early childhood exposure to phthalates and childhood behavior at age 7 years

BACKGROUND

Emerging evidence suggests that phthalate exposure may be associated with behavior problems in children and that these associations may be sex specific.

METHODS

In a follow up study of 411 inner-city minority mothers and their children, mono-n-butyl phthalate (MnBP), monobenzyl phthalate (MBzP), monoisobutyl phthalate (MiBP), monethyl phthalate (MEP) and four di-2-ethylhexyl phthalate metabolites (DEHP) were quantified in maternal urine samples collected during the third trimester and in child urine samples at ages 3 and 5 years. The Conners' Parent Rating Scale-Revised: Long Form (CPRS) and Child Behavior Checklist (CBCL) were administered to the mothers to assess children's behavior problems at 7 years of age. The analysis included children with available measures of CBCL, CPRS and phthalates measured in maternal urine. We performed both Quasi-Poisson regression and a mixture analysis using Weighted Quantile Sum(WQS) regression to assess the risk for CPRS scores and for internalizing and externalizing behaviors (from the CBCL) following intra-uterine exposure to the phthalate metabolites for boys and girls separately.

RESULTS

Among boys, increases in in anxious-shy behaviors were associated with prenatal exposure to MBzP (Mean Ratio [MR] = 1.20, 95%CI 1.05-1.36) and MiBP (Mean Ratio (MR) = 1.22, 95%CI 1.02-1.47). Among girls, increases in perfectionism were associated with MBzP (MR = 1.15, 95%CI 1.01-1.30). In both boys and girls, increases in psychosomatic problems were associated with MiBP (MR = 1.28, 95%CI 1.02-1.60), and MnBP (MR = 1.28, 95%CI 1.02-1.59), respectively. Among girls, decreased hyperactivity was associated with two DEHP metabolites, mono(2-ethyl-5-oxohexyl) phthalate (MR = 0.83, 95%CI 0.71-0.98) and mono(2-ethyl-5-hydroxyhexyl) phthalate (MR = 0.85, 95%CI 0.72-0.99). Using weighted Quantile Sum logistic regression, no associations were found between the Weighted Quantile Sum (WQS) of phthalate metabolites and CPRS scores or externalizing and internalizing behaviors. Nonetheless, when the analysis was performed separately for DEHP and non-DEHP metabolites significant associations were found between the WQS of DEHP metabolites and social problems in boys (OR = 2.15, 95%CI 1.13-4.06, p-value = 0.02) anxious-shy problems in girls (OR = 2.19, 95%CI 1.15-4.16, p = 0.02), and emotional lability problems in all children (OR = 0.61, 95%CI 0.38-0.97, p = 0.04). MEHP and MEOHP were the most highly weighted DEHP metabolites in WQS mixture. The analysis performed with CBCL scale corroborated these associations.

CONCLUSION

Concentration of non-DEHP metabolites was associated with anxious-shy behaviors among boys. DEHP phthalate metabolites were associated with decreased hyperactivity and impulsivity among girls on CPRS scores. These findings lend further support to the adverse associations between prenatal phthalate exposure and childhood outcomes, and clearly suggest that such associations are sex and mixture specific.

Perinatal exposure to diets with different n-6:n-3 fatty acid ratios affects olfactory tissue fatty acid composition

The olfactory mucosa (OM) and the olfactory bulb (OB) are responsible for the detection and processing of olfactory signals. Like the brain and retina, they contain high levels of n-3 and n-6 polyunsaturated fatty acids (PUFAs), which are essential for the structure and function of neuronal and non-neuronal cells. Since the influence of the maternal diet on olfactory lipid profiles of the offspring has been poorly explored, we examined the effects of feeding mice during the perinatal period with diets containing an adequate linoleic acid level but either deficient in α-linolenic acid (ALA) or supplemented in n-3 long-chain PUFAs on the lipid composition of dams and weaning offspring olfactory tissues. In both the OM and OB, the low n-3 ALA diet led to a marked reduction in n-3 PUFAs with a concomitant increase in n-6 PUFAs, whereas consumption of the high n-3 PUFA diet reduced n-6 PUFAs and increased n-3 PUFAs. Structural analysis showed that the molecular species profiles of the main phospholipid classes of olfactory tissues from weaning pups were markedly affected by the maternal diets. This study demonstrates that the PUFA status of olfactory tissues is sensitive to diet composition from the early stages of development.

Maternal diet high in Omega-3 fatty acids upregulate genes involved in neurotrophin signalling in fetal brain during pregnancy in C57BL/6 mice

Neurotrophins play a critical role in the development, maintenance, and proper function of the brain. We investigated the effects of maternal diet high in omega (n)-3 polyunsaturated fatty acids (PUFA) on fatty acids composition and the gene expression of neurotrophins in fetal brain at different gestation stages. Female C57BL/6 mice (7-weeks old, n = 8/group) were fed a diet containing high, low or very low n-3 PUFA (9, 3 or 1% w/w, respectively), with an n-6:n-3 PUFA of 5:1, 20:1 and 40:1, respectively, for two weeks before mating and throughout pregnancy. Animals were sacrificed during pregnancy at gestation day 12.5 and 18.5 to determine placental and fetal-brain fatty acids composition. The gene expressions of endothelial lipase (EL) and plasma membrane fatty acid-binding protein (FABPpm) were measured in the placenta, while major facilitator superfamily domain-containing 2a (Mfsd2a), brain-derived neurotrophic factor (BDNF), tropomyosin-receptor kinase (TrK)-B, and cAMP response element-binding protein (CREB) were measured in fetal-brain, using qPCR. The protein expression of phosphorylated CREB (pCREB) was determined using ELISA. The high n-3 PUFA diet increased the mRNA expression of EL, FABPpm, and Mfsd2a at both gestation days, compared to other groups. Docosahexaenoic acid (DHA) and total n-3 PUFA were significantly higher in the high n-3 PUFA group, compared to the other groups at both gestation days. The high n-3 PUFA diet also increased the mRNA expressions of BDNF, TrKB and CREB, as well as the protein concentration of pCREB as gestation progressed, compared to the other groups. Our findings show for the first time that maternal diet high in n-3 PUFA increased the mRNA expression of Mfsd2a, which correlated with an increase in DHA accretion in the fetal-brain. A diet high in n-3 PUFA increased neurotrophin signalling in fetal-brain as gestation progressed, demonstrating the importance of n-3 PUFA during brain development.

Relationship between the effect of polyunsaturated fatty acids (PUFAs) on brain plasticity and the improvement on cognition and behavior in individuals with autism spectrum disorder

Objective: This work aimed to compile information about the neuronal processes in which polyunsaturated fatty acids (PUFAs) could modulate brain plasticity, in order to analyze the role of nutritional intervention with the ω-3 and ω-6 fatty acids as a therapeutic strategy for the Autism Spectrum Disorder (ASD)-related signs and symptoms.Methods: We reviewed different articles reporting the effect of PUFAS on neurite elongation, membrane expansion, cytoskeleton rearrangement and neurotransmission, considering the ASD-related abnormalities in these processes.Results: In accordance to the reviewed studies, it is clear that ASD is one of the neurological conditions associated with an impairment in neuronal plasticity; therefore, PUFAs-rich diet improvements on cognition and behavioral deficits in individuals with autism, could be involved with the regulation of neuronal processes implicated in the atypical brain plasticity related with this neurodevelopmental disorder.Discussion: The behavioral and cognitive improvement observed in individuals with ASD after PUFAs treatment might underlie, at least in part, in the ability of ω-3 and ω-6 fatty acids to induce neurite outgrowth, probably, through the dynamic regulation of the neuronal cytoskeleton along with the expansion of neuronal membranes. Furthermore, it might also be associated with an enhancement of the efficacy of synaptic transmission and the modulation of neurotransmitters release.

Severity of psychosis syndrome and change of metabolic abnormality in chronic schizophrenia patients: Severe negative syndrome may be related to a distinct lipid pathophysiology

Background:

Metabolic abnormality is common among schizophrenia patients. Some metabolic traits were found associated with subgroups of schizophrenia patients.

Objectives:

We examined a possible relationship between metabolic abnormality and psychosis profile in schizophrenia patients.

Method:

Three hundred and seventy-two chronic schizophrenia patients treated with antipsychotics for more than 2 years were assessed with the Positive and Negative Syndrome Scale. A set of metabolic traits was measured at scheduled checkpoints between October 2004 and September 2006.

Results:

Multiple regressions adjusted for sex showed negative correlations between body mass index (BMI) and total score and all subscales; triglycerides (TG) was negatively correlated with total score and negative syndrome, while HDLC was positively correlated with negative syndrome. When sex interaction was concerned, total score was negatively correlated with BMI but not with others; negative syndrome was negatively correlated with BMI and positively with HDLC. No metabolic traits were correlated with positive syndrome or general psychopathology.

Conclusions:

Loss of body weight is a serious health problem in schizophrenia patients with severe psychosis syndrome, especially the negative syndrome. Schizophrenia patients with severe negative syndrome may have a distinct lipid pathophysiology in comparison with those who were less severe in the domain.

Changes in behavior and fatty acid composition induced by long-term reduction in murine Δ6-desaturation activity

Polyunsaturated fatty acids (PUFAs), especially arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), play an important role in biological regulation. In our previous study using mice deficient in Δ6 desaturase (D6D), we reported that ARA is required for body growth, while DHA is necessary for functional development. In mammals, ARA and DHA are supplied directly or by synthesis from linoleic acid (LA) and α-linolenic acid (ALA). However, as desaturase enzyme activity is immature or low in newborns, and humans with minor alleles of the gene encoding desaturase, respectively, they require dietary supplementation with ARA and DHA. To investigate how the body reacts to a long-term reduction in fatty acid synthesis, we measured behavioral changes and fatty acid composition in mice heterozygous for the D6D null mutation with reduced D6D activity fed a diet containing only LA and ALA as PUFAs. During the growth-maturity period, heterozygous mice showed a slightly change in interest and curiosity compared with the wild-type group. ARA levels were decreased in the brain and liver in the heterozygous group, especially during the growth-maturity period, whereas DHA levels were decreased in the liver only in the old age period, suggesting that there are differences in the synthesis of and demand for ARA and DHA during life. For newborns, and humans with minor alleles with low desaturase activity, direct ARA intake is particularly important during the growth-maturity period, but they may need to be supplemented with DHA in the old age period. Further research is needed to determine the optimal intake and duration of these fatty acids.

Rapeseed oil fortified with micronutrients improves cognitive alterations associated with metabolic syndrome

Metabolic syndrome represents a major risk factor for severe comorbidities such as cardiovascular diseases or diabetes. It is also associated with an increased prevalence of emotional and cognitive alterations that in turn aggravate the disease and related outcomes. Identifying therapeutic strategies able to improve those alterations is therefore a major socioeconomical and public health challenge. We previously reported that both hippocampal inflammatory processes and neuronal plasticity contribute to the development of emotional and cognitive alterations in db/db mice, an experimental model of metabolic syndrome that displays most of the classical features of the syndrome. In that context, nutritional interventions with known impact on those neurobiological processes appear as a promising alternative to limit the development of neurobiological comorbidities of metabolic syndrome. We therefore tested here whether n-3 polyunsaturated fatty acids (n-3 PUFAs) associated with a cocktail of antioxidants can protect against the development of behavioral alterations that accompany the metabolic syndrome. Thus, this study aimed: 1) to evaluate if a diet supplemented with the plant-derived n-3 PUFA α-linolenic acid (ALA) and antioxidants (provided by n-3 PUFAs-rich rapeseed oil fortified with a mix of naturally constituting antioxidant micronutrients, including coenzyme Q10, tocopherol, and the phenolic compound canolol) improved behavioral alterations in db/db mice, and 2) to decipher the biological mechanisms underlying this behavioral effect. Although the supplemented diet did not improve anxiety-like behavior and inflammatory abnormalities, it reversed hippocampus-dependent spatial memory deficits displayed by db/db mice in a water maze task. It concomitantly changed subunit composition of glutamatergic AMPA and NMDA receptors in the hippocampus that has been shown to modulate synaptic function related to spatial memory. These data suggest that changes in local neuronal plasticity may underlie cognitive improvements in db/db mice fed the supplemented diet. The current findings might therefore provide valuable data for introducing new nutritional strategies for the treatment of behavioral complications associated with MetS.

Neither n-3 Long-Chain PUFA Supplementation of Mothers through Lactation nor of Offspring in a Complementary Food Affects Child Overall or Social-Emotional Development: A 2 × 2 Factorial Randomized Controlled Trial in Rural Ethiopia

BACKGROUND

The n-3 (ω-3) long-chain polyunsaturated fatty acid (LC-PUFA) docosahexaenoic acid (DHA) is essential for optimal brain development. There is a lack of evidence on the effect of postnatal n-3 LC-PUFA supplementation on child development in low-income countries.

OBJECTIVE

We evaluated the efficacy of fish-oil supplementation through lactation or complementary food supplementation on the development of children aged 6-24 mo in rural Ethiopia.

METHODS

We conducted a double-blind randomized controlled trial of n-3 LC-PUFA supplementation for 12 mo using fish-oil capsules [maternal intervention: 215 mg DHA + 285 mg eicosapentaenoic acid (EPA)] or a fish-oil-enriched complementary food supplement (child intervention: 169 mg DHA + 331 mg EPA). In total, 360 pairs of mothers and infants aged 6-12 mo were randomly assigned to 4 arms: maternal intervention and child control, child intervention and maternal control, maternal and child intervention, and maternal and child control. Primary outcomes were overall developmental performance with the use of a culturally adapted Denver II test that assesses personal-social, language, fine-motor, and gross-motor domains and social-emotional developmental performance using the Ages and Stages Questionnaire: Social Emotional at baseline and at 6 and 12 mo. We used mixed-effects models to estimate intervention effects on developmental performance over time (intervention × time interaction).

RESULTS

The evolution in overall and social-emotional developmental performance over time did not differ across study arms (intervention × time: F = 1.09, P = 0.35, and F = 0.61, P = 0.61, respectively). Effects did not change after adjustment for child age, birth order, and nutritional status; maternal age and education; wealth; family size; and breastfeeding frequency. Children's developmental performance significantly decreased during study follow-up (β: -0.03 SDs/mo; 95% CI: -0.04, -0.01 SD/mo; P < 0.01).

CONCLUSIONS

n-3 LC-PUFA supplementation does not affect overall or social-emotional development of children aged 6-24 mo in a low-income setting. Follow-up of the cohort is recommended to determine whether there are long-term effects of the intervention. This trial was registered at clinicaltrials.gov as NCT01817634.

The glycerol-3-phosphate acyltransferase PLAT2 functions in the generation of DHA-rich glycerolipids in Aurantiochytrium limacinum F26-b

Thraustochytrids possess docosahexaenoic acid (DHA, 22:6n-3) as acyl chain(s) of triacylglycerol (TG) and phosphatidylcholine (PC), some of which contain multiple DHAs. However, little is known about how these DHA-rich glycerolipids are produced in thraustochytrids. In this study, we identified PLAT2 in Aurantiochytrium limacinum F26-b as a glycerol-3-phosphate (G3P) acyltransferase (GPAT) by heterologous expression of the gene in budding yeast. Subsequently, we found that GPAT activity was reduced by disruption of the PLAT2 gene in A. limacinum, resulting in a decrease in DHA-containing lysophosphatidic acid (LPA 22:6). Conversely, overexpression of PLAT2 increased both GPAT activity and LPA 22:6. These results indicate that PLAT2 is a GPAT that transfers DHA to G3P in vivo as well as in vitro. Overexpression of the PLAT2 gene increased the production of a two DHA-containing diacylglycerol (DG 44:12), followed by an increase in the three DHA-containing TG (TG 66:18), two-DHA-containing TG (TG 60:12), and two DHA-containing PC (PC 44:12). However, overexpression of PLAT2 did not increase DHA-free DG (DG32:0), which was preferentially converted to three 16:0-containing TG (TG 48:0) but not two 16:0-containing PC (PC 32:0). Collectively, we revealed that DHA-rich glycerolipids are produced from a precursor, LPA 22:6, which is generated by incorporating DHA to G3P by PLAT2 in the A. limacinum.

[Omega-6/omega-3 ratio and cognition in children with epilepsy]

INTRODUCTION

Cognitive impairment is a common consequence of epilepsy in children. This study aimed to assess the ratio of omega-6 to omega-3 fatty acid levels and its impact on cognitive function in children with idiopathic epilepsy.

PATIENTS AND METHODS

We performed a case-control study in 30 children with idiopathic epilepsy and 20 healthy children. We measured levels of alpha-linolenic acid (omega-3) and linoleic acid (omega-6) by means of gas-liquid chromatography. We assessed cognitive function with the Arabic version of the fourth edition of the Stanford-Binet test and the P300 component of event-related potentials. All children had an intelligent quotient greater than 70.

RESULTS

Children with epilepsy had lower levels of omega-3 and higher levels of omega-6 fatty acids and an abnormal omega-6/omega-3 ratio compared to non-epileptic children. We found a significant positive correlation of serum omega-3 levels and a significant negative correlation of serum omega-6 levels with cognitive function scores and P300 latency in children with epilepsy.

CONCLUSION

Children with epilepsy have abnormal ratios of omega-6 to omega-3 fatty acid serum levels, which is associated with impaired cognitive function in these children.

Longitudinal Association between n-3 Long-Chain Polyunsaturated Fatty Acid Intake and Depressive Symptoms: A Population-Based Cohort Study in Japan

It remains unclear whether n-3 long-chain polyunsaturated fatty acids (LCPUFA) have a preventive effect on depression in the general population. This study investigated the longitudinal association between n-3 LCPUFA intake and depressive symptoms in community-dwelling Japanese participants. The participants were aged 40–79 years at baseline in the cohort study, wherein examinations, including the assessment of depressive symptoms and nutritional status, were biennially conducted from 1997 to 2012. The subjects (n = 2335) who had a Center for Epidemiologic Studies Depression Scale (CES-D) score < 16 at the first examination and who participated in the follow-up study at least once were included in the analysis. The follow-up end point was the first onset (CES-D ≥ 16) or the last examination participation. Hazard ratios (95% CIs) for CES-D ≥ 16 were estimated using the adjusted Cox proportional hazards model. Overall, 22.1% participants showed depressive symptoms during follow-up (average; 8.1 years). Compared with the lowest tertile, the highest HR for EPA was 0.74 (0.60–0.93), and highest and middle HRs for DHA were 0.79 (0.63–0.98) and 0.80 (0.65–0.99) (P for trend = 0.009 and 0.032), respectively. Among populations with high fish consumption, higher n-3 LCPUFA intake may be associated with a low risk of depressive symptoms.

Effects of soft electrophiles on selenium physiology

This review examines the effects of neurotoxic electrophiles on selenium (Se) metabolism. Selenium-dependent enzymes depend on the unique and elite functions of selenocysteine (Sec), the 21st proteinogenic amino acid, to perform their biochemical roles. Humans possess 25 selenoprotein genes, ~ half of which are enzymes (selenoenzymes) required for preventing, controlling, or reversing oxidative damage, while others participate in regulating calcium metabolism, thyroid hormone status, protein folding, cytoskeletal structure, Sec synthesis and Se transport. While selenoproteins are expressed in tissue dependent distributions and levels in all cells of all vertebrates, they are particularly important in brain development, health, and functions. As the most potent intracellular nucleophile, Sec is subject to binding by mercury (Hg) and other electron poor soft neurotoxic electrophiles. Epidemiological and environmental studies of the effects of exposures to methyl-Hg (CH₃Hg⁺), elemental Hg (Hg°), and/or other metallic/organic neurotoxic soft electrophiles need to consider the concomitant effects of all members of this class of toxicants in relation to the Se status of their study populations. The contributions of individual electrophiles' discrete and cooperative rates of Se sequestration need to be evaluated in relation to tissue Se reserves of the exposed populations to identify sensitive subgroups which may be at accentuated risk due to poor Se status. Additional study is required to examine possibilities of inherited, acquired, or degenerative neurological disorders of Se homeostasis that may influence vulnerability to soft electrophile exposures. Investigations of soft electrophile toxicity will be enhanced by considering the concomitant effects of combined exposures on tissue Se-availability in relation to pathological consequences during fetal development or in relation to etiologies of neurological disorders and neurodegenerative diseases. Since selenoenzymes are molecular "targets" of soft electrophiles, concomitant evaluation of aggregate exposures to these toxicants in relation to dietary Se intakes will assist regulatory agencies in their goals of improving and protecting public health.

Maternal long chain polyunsaturated fatty acid status and pregnancy complications

Maternal nutrition plays a crucial role in influencing fetal growth and birth outcome. Any nutritional insult starting several weeks before pregnancy and during critical periods of gestation is known to influence fetal development and increase the risk for diseases during later life. Literature suggests that chronic adult diseases may have their origin during early life - a concept referred to as Developmental Origins of Health and Disease (DOHaD) which states that adverse exposures early in life "program" risks for later chronic disorders. Long chain polyunsaturated fatty acids (LCPUFA), mainly omega-6 and omega-3 fatty acids are known to have an effect on fetal programming. The placental supply of optimal levels of LCPUFA to the fetus during early life is extremely important for the normal growth and development of both placenta and fetus. Any alteration in placental development will result in adverse pregnancy outcome such as gestational diabetes mellitus (GDM), preeclampsia, and intrauterine growth restriction (IUGR). A disturbed materno-fetal LCPUFA supply is known to be linked with each of these pathologies. Further, a disturbed LCPUFA metabolism is reported to be associated with a number of metabolic disorders. It is likely that LCPUFA supplementation during early pregnancy may be beneficial in improving the health of the mother, improving birth outcome and thereby reducing the risk of diseases in later life.

Balanced diets in food systems: Emerging trends and challenges for human health

Processed foods, generally known as modified raw foods produced by innovative processing technologies alters the food constituents such natural enzymes, fatty acids, micronutrients, macronutrients and vitamins. In contrast to fresh and unprocessed foods, processed foods are guaranteed to be safer, imperishable, long lasting and consist high level of nutrients bioactivity. Currently, the evolution in food processing technologies is necessary to face food security and safety, nutrition demand, its availability and also other global challenges in the food system. In this scenario, this review consists of information on two food processing technologies, which effects on processed foods before and after processing and the impact of food products on human health. It is also very well established that understanding the type and structure of foods to be processed can assist food processing industries towards advancement of novel food products. In connection with this fact, the present article also discusses the emerging trends and possible modifications in food processing technologies with the combination of conventional and modern techniques to get the suitable nutritional and safety qualities in food.

Maternal n-3 polyunsaturated fatty acid dietary supply modulates microglia lipid content in the offspring

The brain is highly enriched in long chain polyunsaturated fatty acids (LC-PUFAs) that are esterified into phospholipids, the major components of cell membranes. They accumulate during the perinatal period when the brain is rapidly developing. Hence, the levels of LC-PUFAs in the brains of the offspring greatly depend on maternal dietary intake. Perinatal n-3 PUFA consumption has been suggested to modulate the activity of microglial cells, the brain's innate immune cells which contribute to the shaping of neuronal network during development. However, the impact of maternal n-3 PUFA intake on microglial lipid composition in the offspring has never been studied. To investigate the impact of maternal dietary n-3 PUFA supply on microglia lipid composition, pregnant mice were fed with n-3 PUFA deficient, n-3 PUFA balanced or n-3 PUFA supplemented diets during gestation and lactation. At weaning, microglia were isolated from the pup's brains to analyze their fatty acid composition and phospholipid class levels. We here report that post-natal microglial cells displayed a distinctive lipid profile as they contained high levels of eicosapentaenoic acid (EPA), more EPA than docosahexaenoic acid (DHA) and large amount of phosphatidylinositol (PI) / phosphatidylserine (PS). Maternal n-3 PUFA supply increased DHA levels and decreased n-6 docosapentaenoic acid (DPA) levels whereas the PI/PS membrane content was inversely correlated to the quantity of PUFAs in the diet. These results raise the possibility of modulating microglial lipid profile and their subsequent activity in the developing brain.

Omega 3 Consumption and Anxiety Disorders: A Cross-Sectional Analysis of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

Few studies have evaluated the association between diet and mental disorders, and it has been established that &omega;-3 (n-3) fatty acids may have a beneficial effect for sufferers of anxiety disorders. This study is part of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)&mdash;a population-based cohort study on diet and mental health&mdash;and searched for associations between anxiety disorders and consumption of n-3 polyunsaturated fatty acids (PUFA). The study had a cross-sectional design, with a total sample of 12,268 adults. Dietary exposure was measured by a quantitative food-frequency questionnaire, and mental diagnoses were assessed by the Clinical Interview Schedule&mdash;Revised Version and diagnosed according to the International Classification of Diseases (ICD-10). Logistic regression models were built using quintiles of n-3, &omega; 6 (n-6), n-6/n-3 ratio, and PUFA, using the 1st quintile as reference. Anxiety disorders were identified in 15.4% of the sample. After adjusting for sociodemographic variables, cardiovascular risk factors, diet variables, and depression, intakes in the 5th quintile were inversely associated with anxiety disorders for EPA (OR = 0.82, 95% CI = 0.69⁻0.98), DHA (OR = 0.83, 95% CI = 0.69⁻0.98), and DPA (OR = 0.82, 95% CI = 0.69⁻0.98). Participants in the fifth quintile of n-6/n-3 ratio had a positive association with anxiety disorders. Although results suggest a possible protective effect of n-3 fatty acids against anxiety, all associations lost significance after adjustment for multiple comparisons.

Maternal DHA Status during Pregnancy Has a Positive Impact on Infant Problem Solving: A Norwegian Prospective Observation Study

Docosahexaenoic acid (DHA, 22:6, n-3) is a long-chain polyunsaturated fatty acid necessary for normal brain growth and cognitive development. Seafood and dietary supplements are the primary dietary sources of DHA. This study addresses the associations between DHA status in pregnant women and healthy, term-born infant problem-solving skills assessed using the Ages and Stages Questionnaire. The fatty acid status of maternal red blood cells (RBCs) was assessed in the 28th week of gestation and at three months postpartum. The infants’ fatty acid status (RBC) was assessed at three, six, and twelve months, and problem-solving skills were assessed at six and twelve months. Maternal DHA status in pregnancy was found to be positively associated with infants’ problem-solving skills at 12 months. This association remained significant even after controlling for the level of maternal education, a surrogate for socio-economic status. The infants’ DHA status at three months was associated with the infants’ problem solving at 12 months. The results accentuate the importance for pregnant and lactating women to have a satisfactory DHA status from dietary intake of seafood or other sources rich in DHA.

Of Meat and Men: Sex Differences in Implicit and Explicit Attitudes Toward Meat

Modern attitudes to meat in both men and women reflect a strong meat-masculinity association. Sex differences in the relationship between meat and masculinity have not been previously explored. In the current study we used two IATs (implicit association tasks), a visual search task, and a questionnaire to measure implicit and explicit attitudes toward meat in men and women. Men exhibited stronger implicit associations between meat and healthiness than did women, but both sexes associated meat more strongly with 'healthy' than 'unhealthy' concepts. As 'healthy' was operationalized in the current study using terms such as "virile" and "powerful," this suggests that a meat-strength/power association may mediate the meat-masculinity link readily observed across western cultures. The sex difference was not related to explicit attitudes to meat, nor was it attributable to a variety of other factors, such as a generally more positive disposition toward meat in men than women. Men also exhibited an attention bias toward meats, compared to non-meat foods, while females exhibited more caution when searching for non-meat foods, compared to meat. These biases were not related to implicit attitudes, but did tend to increase with increasing hunger levels. Potential ultimate explanations for these differences, including sex differences in bio-physiological needs and receptivity to social signals are discussed.

[The role of brain n-3 fatty acids-GPR40/FFAR1 signaling in pain]

G-protein-coupled receptor 40 (GPR40)/free fatty acid receptor (FFAR) 1 is activated by long-chain fatty acids such as docosahexaenoic acid (DHA). Its receptor is expressed predominantly in the central nervous system (CNS) and in β-cells in the pancreatic Islets. We have already demonstrated that the intracerebroventricular administration of DHA or GW9508, a GPR40/FFAR1 agonist, suppresses formalin-induced pain behavior. It also attenuates complete Freund's adjuvant-induced mechanical allodynia and thermal hyperalgesia, suggesting that these effects occur by increasing β-endorphin release from propiomelanocortin neurons. Furthermore, we found that the brain GPR40/FFAR1 signaling may involve in the regulation of the descending pain control system, whereas the deletion of GPR40/FFAR1 might exacerbate mechanical allodynia in postoperative pain. Therefore, it is possible that the brain n-3 fatty acid-GPR40/FFAR1 signaling may play a key role in the modulation of the endogenous pain control system and emotional function. Here, we discuss the role of brain n-3 fatty acids-GPR40/FFAR1 signaling in a pain, and we review the current status and future prospects of the brain GPR40/FFAR1.

Postnatal polyunsaturated fatty acids associated with larger preterm brain tissue volumes and better outcomes

BackgroundHuman studies investigating the link between postnatal polyunsaturated fatty acids and preterm brain growth are limited, despite emerging evidence of potential effects on outcomes.MethodsSixty preterm neonates <32 weeks gestational age with magnetic resonance imaging (MRI) scanning at near-birth and near-term age were assessed for brain tissue volumes, including cortical gray matter, white matter, deep gray matter, cerebellum, brainstem, and ventricular cerebrospinal fluid. Red blood cell fatty acid content was evaluated within 1 week of each MRI scan. Neurodevelopmental outcome at 30-36 months corrected age was assessed.ResultsAdjusting for potential confounders, higher near-birth docosahexaenoic acid levels are associated with larger cortical gray matter, deep gray matter, and brainstem volumes and higher near-term levels with larger deep gray matter, cerebellar, and brainstem volumes at near-term age; lower near-birth linoleic acid levels are correlated with larger white matter volume at near-term age. By 30-36 months corrected age, larger cortical and deep gray matter, cerebellar, and brainstem volumes by term age are associated with improved language scores and larger cerebellar and brainstem volumes with improved motor scores.ConclusionSpecific polyunsaturated fatty acid levels have differential and time-dependent associations with brain region growth. Larger brain volumes are associated with improved outcomes at preschool age.

N-3 (Omega-3) Fatty Acids: Effects on Brain Dopamine Systems and Potential Role in the Etiology and Treatment of Neuropsychiatric Disorders

BACKGROUND & OBJECTIVE

A number of neuropsychiatric disorders, including Parkinson's disease, schizophrenia, attention deficit hyperactivity disorder, and, to some extent, depression, involve dysregulation of the brain dopamine systems. The etiology of these diseases is multifactorial, involving genetic and environmental factors. Evidence suggests that inadequate levels of n-3 (omega- 3) polyunsaturated fatty acids (PUFA) in the brain may represent a risk factor for these disorders. These fatty acids, which are derived from the diet, are a major component of neuronal membranes and are of particular importance in brain development and function. Low levels of n-3 PUFAs in the brain affect the brain dopamine systems and, when combined with appropriate genetic and other factors, increase the risk of developing these disorders and/or the severity of the disease. This article reviews the neurobiology of n-3 PUFAs and their effects on dopaminergic function.

CONCLUSION

Clinical studies supporting their role in the etiologies of diseases involving the brain dopamine systems and the potential of n-3 PUFAs in the treatment of these disorders are discussed.

DHA Mitigates Autistic Behaviors Accompanied by Dopaminergic Change in a Gene/Prenatal Stress Mouse Model

Autism Spectrum Disorder (ASD) is characterized by impairments in social interaction, social communication, and repetitive and stereotyped behaviors. Recent work has begun to explore gene × environmental interactions in the etiology of ASD. We previously reported that prenatal stress exposure in stress-susceptible heterozygous serotonin transporter (SERT) KO pregnant dams in a mouse model resulted in autism-like behavior in the offspring (SERT/S mice). The association between prenatal stress and ASD appears to be affected by maternal SERT genotype in clinical populations as well. Using the mouse model, we examined autistic-like behaviors in greater detail, and additionally explored whether diet supplementation with docosahexaenoic acid (DHA) may mitigate the behavioral changes. Only male SERT/S mice showed social impairment and stereotyped behavior, and DHA supplementation ameliorated some of these behaviors. We also measured monoamine levels in the SERT/S mice after three treatment paradigms: DHA-rich diet continuously from breeding (DHA diet), DHA-rich diet only after weaning (CTL/DHA diet) and control diet only (CTL diet). The dopamine (DA) content in the striatum was significantly increased in the SERT/S mice compared with wild-type (WT) mice, whereas no difference was observed with noradrenaline and serotonin content. Moreover, DA content in the striatum was significantly reduced in the SERT/S mice with the DHA-rich diet provided continuously from breeding. The results indicate that autism-associated behaviors and changes in the dopaminergic system in this setting can be mitigated with DHA supplementation.

Attenuation of Lead-Induced Neurotoxicity by Omega-3 Fatty Acid in Rats

Background

Lead is widely distributed in the environment and has been found to be associated with various health problems including neurodegenerative diseases.

Purpose

In view of the increasing health risk caused by lead, this study has been carried out to investigate the neuroprotective effect of omega-3 fatty acid (omega-3FA) in lead-induced neurotoxicity in rats.

Methods

Biochemical parameters including oxidative stress in brain regions, lead levels in blood and brain regions and histopathological examination of brain regions of rats were carried out in the present study.

Results

Rats exposed to lead (lead acetate 7.5 mg/kg body weight p.o. for 14 days) caused a significant increase in the levels of lipid peroxidation, protein carbonyl content, ROS production and decreased the activities of glutathione peroxidase, superoxide dismutase and catalase in the cerebellum and cerebral cortex, respectively, as compared to controls. Abnormal histopathological changes and increase in the levels of lead in blood and brain were also observed as compared to controls. Co-treatment of lead with omega-3FA (750 mg/kg body weight p.o. for 14 days) decreased the levels of lipid peroxidation, protein carbonyl content, ROS production and increased the activities of glutathione peroxidase, superoxide dismutase and catalase and showed protection in the histopathological study as compared to rats treated with lead alone.

Conclusions

The result of the present study shows that lead-induced oxidative stress and histopathological alteration in the brain region were significantly protected with co-treatment of lead and omega-3FA. This could be due to its strong antioxidant potential and metal-binding property.

The effect of dietary supplements on clinical aspects of autism spectrum disorder: A systematic review of the literature

BACKGROUND

Autism spectrum disorder is associated with significant social and financial burden and no definite treatment for this entity has been identified, yet. In recent years there has been an increasing interest in the use of dietary interventions as a complementary therapeutic option for these patients.

OBJECTIVE

The aim of this systematic review is to provide high evidence level literature data about the effect of dietary supplements on clinical aspects of children with autism.

METHODS

A comprehensive literature search was conducted using Pubmed as the medical database source. Randomized controlled trials conducted in pediatric populations and including measures of clinical outcomes were considered.

RESULTS

A total of 17 eligible prospective studies were selected. Types of dietary supplements evaluated in these studies included amino acids, fatty acids and vitamins/minerals. N-acetylcysteine was shown to exert a beneficial effect on symptoms of irritability. On the other hand, literature data about the efficacy of d-cycloserine and pyridoxine-magnesium supplements was controversial. No significant effect was identified for fatty acids, N,N-dimethylglycine and inositol. Literature data about ascorbic acid and methyl B12 was few, although some encouraging results were found. No serious adverse events were reported in the vast majority of the studies, while the prevalence of adverse reactions was similar between treatment and placebo groups.

CONCLUSIONS

The use of dietary supplements in children with autism seems to be a safe practice with encouraging data about their clinical efficacy. More studies are needed to further investigate this issue.