Low docosahexaenoic acid status is associated with reduced indices in cortical integrity in the anterior cingulate of healthy male children: a 1H MRS Study

Familial risk for bipolar I disorder is associated with erythrocyte omega-3 polyunsaturated fatty acid deficits in youth with attention-deficit hyperactivity disorder

Although attention-deficit/hyperactivity disorder (ADHD) and a family history of bipolar I disorder (BD) increase the risk for developing BD, associated pathoetiological mechanisms remain poorly understood. One candidate risk factor is a neurodevelopmental deficiency in omega-3 polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study investigated erythrocyte EPA+DHA biostatus in psychostimulant-free ADHD youth with ('high-risk', HR) and without ('low-risk', LR) a first-degree relative with BD, and healthy controls (HC). Erythrocyte EPA+DHA composition was determined by gas chromatography, and symptom ratings were performed. A total of n = 123 (HR, n = 41; LR, n = 42; HC, n = 40) youth (mean age: 14.4 ± 2.5 years) were included in the analysis. Compared with HC, erythrocyte EPA+DHA composition was significantly lower in HR (-13%) but not LR (-3%), and there was a trend for HR to be lower than LR (-11%). Both HR and LR differed significantly from HC on all symptom ratings. HR had greater ADHD hyperactivity/impulsive symptom severity, manic symptom severity, and higher parent-reported ratings of internalization, externalization, and dysregulation, compared with LR. ADHD youth with a BD family history exhibit erythrocyte EPA+DHA deficits and a more severe clinical profile, including greater manic and dysregulation symptoms, compared with ADHD youth without a BD family history.

Prenatal docosahexaenoic acid supplementation has long-term effects on childhood behavioral and brain responses during performance on an inhibitory task

Introduction: Offsprings from a prenatal docosahexaenoic acid (DHA) supplementation trial, in which pregnant women were assigned to placebo or 600mg DHA/day, were followed to determine the effect of prenatal DHA supplementation on the behavior and brain function at 5.5 years (n=81 placebo, n=86 supplemented).Methods: Event-related potentials (ERP) were recorded during a visual task requiring a button press (Go) to frequent target stimuli and response inhibition to the rare stimuli (No-Go). Univariate ANOVAs were used to test differences between group and sex for behavioral measures. ERP differences were tested using a three-way mixed-design multivariate analysis of variance (MANOVA).Results: There was a significant sex × group interaction for hit rate and errors of omission; there was no difference between males and females in the placebo group, but DHA males outperformed DHA females. Males overall and the placebo group made more errors requiring response inhibition; DHA females were significantly better than placebo females and DHA males. ERP P2 amplitude was larger in the DHA group. A significant N2 amplitude condition effect was observed in females and DHA group males, but not in placebo group males.Discussion: Prenatal DHA supplementation improved inhibitory performance overall, especially for females in the DHA group, possibly accounting for their conservative behavior during Go trials. Development of brain regions responsible for visual processing may be sensitive to maternal DHA status, evidenced by greater P2 amplitude. Males may benefit more from maternal DHA supplementation, indicated by the N2 condition effect seen only in males in the DHA group.

Effects of dietary omega-3 intake on vigilant attention and resting-state functional connectivity in neurotypical children and adolescents

BACKGROUND

Vigilant Attention (VA) is a critical cognitive function allowing to maintain our attention, particularly in redundant or intellectually unchallenging situations. Evidence has shown that, as the brain develops, VA abilities rapidly improve throughout childhood and adolescence. Dietary omega-3 polyunsaturated fats (PUFA), playing a critical role for proper brain development and maturation of cortical regions, may contribute to variations in VA abilities.

OBJECTIVE

The present study investigated the effect of dietary omega-3 PUFA intake (docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)) on resting-state functional connectivity (rsFC) of a meta-analytically defined VA network in 24 neurotypical children and adolescents (7.3-17.2 years) from the Healthy Brain Network databank.

METHODS

Functional MRI and phenotypical information were collected from the Healthy Brain Network databank. Intake of omega-3 DHA and EPA was assessed using a food frequency questionnaire and was adjusted for total calorie intake. Out of scanner VA-related performance was assessed using the VA condition of the Adaptive Cognitive Evaluation tool.

RESULTS

Overall, reported intake of omega-3 PUFA was not significantly associated with VA-related performance. Furthermore, energy-adjusted omega-3 intake was not significantly correlated with rsFC within the VA network. A complementary whole-brain analysis revealed that energy-adjusted omega-3 intake was correlated with decreased rsFC between parieto-occipital brain regions.

CONCLUSION

The present study was not able to detect a relationship between dietary omega-3 and rsFC or VA performance.

Effects of Maternal Fish Oil and/or 5-Methyl-Tetrahydrofolate Supplementation during Pregnancy on Offspring Brain Resting-State at 10 Years Old: A Follow-Up Study from the NUHEAL Randomized Controlled Trial

Recent studies have shown that maternal supplementation with folate and long-chain polyunsaturated fatty acids (LC-PUFAs) during pregnancy may affect children's brain development. We aimed at examining the potential long-term effect of maternal supplementation with fish oil (FO) and/or 5-methyl-tetrahydrofolate (5-MTHF) on the brain functionality of offspring at the age of 9.5-10 years. The current study was conducted as a follow-up of the Spanish participants belonging to the Nutraceuticals for a Healthier Life (NUHEAL) project; 57 children were divided into groups according to mother's supplementation and assessed through functional magnetic resonance imaging (fMRI) scanning and neurodevelopment testing. Independent component analysis and double regression methods were implemented to investigate plausible associations. Children born to mothers supplemented with FO (FO and FO + 5-MTHF groups, n = 33) showed weaker functional connectivity in the default mode (DM) (angular gyrus), the sensorimotor (SM) (motor and somatosensory cortices) and the fronto-parietal (FP) (angular gyrus) networks compared to the No-FO group (placebo and 5-MTHF groups, n = 24) (PFWE < 0.05). Furthermore, no differences were found regarding the neuropsychological tests, except for a trend of better results in an object recall (memory) test. Considering the No-FO group, the aforementioned networks were associated negatively with attention and speed-processing functions. Mother's FO supplementation during pregnancy seems to be able to shape resting-state network functioning in their children at school age and appears to produce long-term effects on children´s cognitive processing.

Relationship between whole blood omega-3 fatty acid levels and dorsal cingulate gray matter volume: Sex differences and implications for impulse control

During adolescence, the prefrontal cortex (PFC) undergoes substantial structural development, including cortical thinning, a process associated with improvements in behavioral control. The cingulate cortex is among the regions recruited in response inhibition and mounting evidence suggests cingulate function may be sensitive to availability of an essential dietary nutrient, omega-3 fatty acids (N3; i.e. EPA + DHA). Our primary aim was to investigate the relationship between a biomarker of omega-3 fatty acids -- percent of whole blood fatty acids as EPA + DHA (N3 Index) -- and cingulate morphology, in typically developing adolescent males (n = 29) and females (n = 33). Voxel-based morphometry (VBM) was used to quantify gray matter volume (GMV) in the dorsal region of the cingulate (dCC). Impulse control was assessed via caregiver report (BRIEF) and Go/No-Go task performance. We predicted that greater N3 Index in adolescents would be associated with less dCC GMV and better impulse control. Results revealed that N3 Index was inversely related to GMV in males, but not in females. Furthermore, males with less right dCC GMV exhibited better caregiver-rated impulse control. A simple mediation model revealed that, in males, N3 Index may indirectly impact impulse control through its association with right dCC GMV. Findings suggest a sex-specific link between levels of N3 and dCC structural development, with adolescent males more impacted by lower N3 levels than females. Identifying factors such as omega-3 fatty acid levels, which may modulate the neurodevelopment of response inhibition, is critical for understanding typical and atypical developmental trajectories associated with this core executive function.

Choline and DHA in Maternal and Infant Nutrition: Synergistic Implications in Brain and Eye Health

The aim of this review is to highlight current insights into the roles of choline and docosahexaenoic acid (DHA) in maternal and infant nutrition, with special emphasis on dietary recommendations, gaps in dietary intake, and synergistic implications of both nutrients in infant brain and eye development. Adequate choline and DHA intakes are not being met by the vast majority of US adults, and even more so by women of child-bearing age. Choline and DHA play a significant role in infant brain and eye development, with inadequate intakes leading to visual and neurocognitive deficits. Emerging findings illustrate synergistic interactions between choline and DHA, indicating that insufficient intakes of one or both could have lifelong deleterious impacts on both maternal and infant health.

Dietary Long-Chain Omega-3 Fatty Acids Are Related to Impulse Control and Anterior Cingulate Function in Adolescents

Impulse control, an emergent function modulated by the prefrontal cortex (PFC), helps to dampen risky behaviors during adolescence. Influences on PFC maturation during this period may contribute to variations in impulse control. Availability of omega-3 fatty acids, an essential dietary nutrient integral to neuronal structure and function, may be one such influence. This study examined whether intake of energy-adjusted long-chain omega-3 fatty acids [eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA)] was related to variation in impulse control and PFC activity during performance of an inhibitory task in adolescents (n = 87; 51.7% female, mean age 13.3 ± 1.1 years) enrolled in a longitudinal neuroimaging study. Intake of DHA + EPA was assessed using a food frequency questionnaire and adjusted for total energy intake. Inhibitory control was assessed using caregiver rating scale (BRIEF Inhibit subscale) and task performance (false alarm rate) on a Go/No-Go task performed during functional MRI. Reported intake of long-chain omega-3 was positively associated with caregiver ratings of adolescent ability to control impulses (p = 0.017) and there was a trend for an association between intake and task-based impulse control (p = 0.072). Furthermore, a regression of BOLD response within PFC during successful impulse control (Correct No-Go versus Incorrect No-Go) with energy-adjusted DHA + EPA intake revealed that adolescents reporting lower intakes display greater activation in the dorsal anterior cingulate, potentially suggestive of a possible lag in cortical development. The present results suggest that dietary omega-3 fatty acids are related to development of both impulse control and function of the dorsal anterior cingulate gyrus in normative adolescent development. Insufficiency of dietary omega-3 fatty acids during this developmental period may be a factor which hinders development of behavioral control.

Nutrient biomarkers shape individual differences in functional brain connectivity: Evidence from omega-3 PUFAs

A wealth of neuroscience evidence demonstrates that diet and nutrition play an important role in structural brain plasticity, promoting the development of gray matter volume and maintenance of white matter integrity across the lifespan. However, the role of nutrition in shaping individual differences in the functional brain connectome remains to be well established. We therefore investigated whether nutrient biomarkers known to have beneficial effects on brain structure (i.e., the omega-3 polyunsaturated fatty acids; ω-3 PUFAs), explain individual differences in functional brain connectivity within healthy older adults (N = 96). Our findings demonstrate that ω-3 PUFAs are associated with individual differences in functional connectivity within regions that support executive function (prefrontal cortex), memory (hippocampus), and emotion (amygdala), and provide key evidence that the influence of these regions on global network connectivity reliably predict general, fluid, and crystallized intelligence. The observed findings not only elucidate the role of ω-3 PUFAs in functional brain plasticity and intelligence, but also motivate future studies to examine their impact on psychological health, aging, and disease.

Long-chain polyunsaturated fatty acid supplementation in the first year of life affects brain function, structure, and metabolism at age nine years

The present study sought to determine whether supplementation of long-chain polyunsaturated fatty acids (LCPUFA) during the first year of life influenced brain function, structure, and metabolism at 9 years of age. Newborns were randomly assigned to consume formula containing either no LCPUFA (control) or formula with 0.64% of total fatty acids as arachidonic acid (ARA; 20:4n6) and variable amounts of docosahexaenoic acid (DHA; 22:6n3) (0.32%, 0.64%, or 0.96% of total fatty acids) from birth to 12 months. At age 9 years (±0.6), 42 children enrolled in a follow-up multimodal magnetic resonance imaging (MRI) study including functional (fMRI, Flanker task), resting state (rsMRI), anatomic, and proton magnetic resonance spectroscopy (¹ H MRS). fMRI analysis using the Flanker task found that trials requiring greater inhibition elicited greater brain activation in LCPUFA-supplemented children in anterior cingulate cortex (ACC) and parietal regions. rsMRI analysis showed that children in the 0.64% group exhibited greater connectivity between prefrontal and parietal regions compared to all other groups. In addition, voxel-based analysis (VBM) revealed that the 0.32% and 0.64% groups had greater white matter volume in ACC and parietal regions compared to controls and the 0.96% group. Finally, ¹ H MRS data analysis identified that N-acetylaspartate (NAA) and myo-inositol (mI) were higher in LCPUFA groups compared to the control group. LCPUFA supplementation during infancy has lasting effects on brain structure, function, and neurochemical concentrations in regions associated with attention (parietal) and inhibition (ACC), as well as neurochemicals associated with neuronal integrity (NAA) and brain cell signaling (mI).

Role of polyunsaturated fatty acids in human brain structure and function across the lifespan: An update on neuroimaging findings

There is a substantial body of evidence from animal studies implicating polyunsaturated fatty acids (PUFA) in neuroinflammatory, neurotrophic, and neuroprotective processes in brain. However, direct evidence for a role of PUFA in human brain structure and function has been lacking. Over the last decade there has been a notable increase in neuroimaging studies that have investigated the impact of PUFA intake and/or blood levels (i.e., biostatus) on brain structure, function, and pathology in human subjects. The majority of these studies specifically evaluated associations between omega-3 PUFA intake and/or biostatus and neuroimaging outcomes using a variety of experimental designs and imaging techniques. This review provides an updated overview of these studies in an effort to identify patterns to guide and inform future research. While the weight of evidence provides general support for a beneficial effect of a habitual diet consisting of higher omega-3 PUFA intake on cortical structure and function in healthy human subjects, additional research is needed to replicate and extend these findings as well as identify response mediators and clarify mechanistic pathways. Controlled intervention trials are also needed to determine whether increasing n-3 PUFA biostatus can prevent or attenuate neuropathological brain changes observed in patients with or at risk for psychiatric disorders and dementia.

Putative Astroglial Dysfunction in Schizophrenia: A Meta-Analysis of 1H-MRS Studies of Medial Prefrontal Myo-Inositol

Background: Several lines of evidence support a role for astroglial pathology in schizophrenia. Myo-inositol is particularly abundant in astroglia. Many small sized studies have reported on myo-inositol concentration in schizophrenia, but to date these have not been pooled to estimate a collective effect size. Methods: We reviewed all proton magnetic resonance spectroscopy (1H-MRS) studies reporting myo-inositol values for patients satisfying DSM or ICD based criteria for schizophrenia in comparison to a healthy controls group in the medial prefrontal cortex published until February 2018. A random-effects model was used to calculate the pooled effect size using metafor package. A meta-regression analysis of moderator variables was also undertaken. Results: The literature search identified 19 studies published with a total sample size of 585 controls, 561 patients with schizophrenia. Patients with schizophrenia had significantly reduced medial prefrontal myo-inositol compared to controls (RFX standardized mean difference = 0.19, 95% CI [0.05-0.32], z = 2.72, p = 0.0067; heterogeneity p = 0.09). Studies with more female patients reported more notable schizophrenia-related reduction in myo-inositol (z = 2.53, p = 0.011). Discussion: We report a small, but significant reduction in myo-inositol concentration in the medial prefrontal cortex in schizophrenia. The size of the reported effect indicates that the biological pathways affecting the astroglia are likely to operate only in a subset of patients with schizophrenia. MRS myo-inositol could be a useful tool to stratify and investigate such patients.

Polyunsaturated fatty acids and recurrent mood disorders: Phenomenology, mechanisms, and clinical application

A body of evidence has implicated dietary deficiency in omega-3 polyunsaturated fatty acids (n-3 PUFA), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in the pathophysiology and etiology of recurrent mood disorders including major depressive disorder (MDD) and bipolar disorder. Cross-national and cross-sectional evidence suggests that greater habitual intake of n-3 PUFA is associated with reduced risk for developing mood symptoms. Meta-analyses provide strong evidence that patients with mood disorders exhibit low blood n-3 PUFA levels which are associated with increased risk for the initial development of mood symptoms in response to inflammation. While the etiology of this n-3 PUFA deficit may be multifactorial, n-3 PUFA supplementation is sufficient to correct this deficit and may also have antidepressant effects. Rodent studies suggest that n-3 PUFA deficiency during perinatal development can recapitulate key neuropathological, neurochemical, and behavioral features associated with mood disorders. Clinical neuroimaging studies suggest that low n-3 PUFA biostatus is associated with abnormalities in cortical structure and function also observed in mood disorders. Collectively, these findings implicate dietary n-3 PUFA insufficiency, particularly during development, in the pathophysiology of mood dysregulation, and support implementation of routine screening for and treatment of n-3 PUFA deficiency in patients with mood disorders.

Polyunsaturated fatty acid biostatus, phospholipase A2 activity and brain white matter microstructure across adolescence

Adolescence is a period of major brain white matter (WM) changes, and membrane lipid metabolism likely plays a critical role in brain WM myelination. Long-chain polyunsaturated fatty acids (LC-PUFAs) are essential components of cell membranes including oligodendrocytes, and LC-PUFA release and turnover in membranes is regulated by phospholipase A₂ enzymes. To investigate the role of membrane lipid metabolism in healthy WM myelination across adolescence, the present study examined the relationship between membrane LC-PUFA biostatus, phospholipase A₂ activity, and brain WM microstructure in healthy subjects aged 9-20years (n=30). Diffusion tensor imaging (DTI) was performed to measure average fractional anisotropy (FA) and diffusivity (indices sensitive to WM myelination) of nine major cerebral WM tracts. Blood samples were collected to measure erythrocyte membrane fatty acid concentrations and plasma intracellular phospholipase A₂ activity (inPLA₂). Plasma inPLA₂ activity showed a significant U-curved association with WM radial diffusivity, and an inverted U-curved association with WM FA, independent of age. A significant positive linear correlation was observed between docosahexaenoic acid concentration and axial diffusivity in the corpus callosum. These findings suggest that there may be optimal physiological inPLA₂ activity levels associated with healthy WM myelination in late childhood and adolescence. Myelination may be mediated by cleavage of docosahexaenoic acid from membrane phospholipids by inPLA₂. These findings have implications for our understanding of the role of LC-PUFA homeostasis in myelin-related neurodevelopmental disorders.

Event-related potential differences in children supplemented with long-chain polyunsaturated fatty acids during infancy

Long-chain polyunsaturated fatty acids (LCPUFA) have been shown to be necessary for early retinal and brain development, but long-term cognitive benefits of LCPUFA in infancy have not been definitively established. The present study sought to determine whether LCPUFA supplementation during the first year of life would result in group differences in behavior and event-related potentials (ERPs) while performing a task requiring response inhibition (Go/No-Go) at 5.5 years of age. As newborns, 69 children were randomly assigned to infant formulas containing either no LCPUFA (control) or formula with 0.64% of total fatty acids as arachidonic acid (ARA; 20:4n6) and various concentrations of docosahexaenoic acid (DHA; 22:6n3) (0.32%, 0.64% or 0.96%) for the first 12 months of life. At 5.5 years of age, a task designed to test the ability to inhibit a prepotent response (Go/No-Go) was administered, yielding both event-related potentials (ERPs) and behavioral data. Behavioral measures did not differ between groups, although reaction times of supplemented children were marginally faster. Unsupplemented children had lower P2 amplitude than supplemented children to both Go and No-Go conditions. N2 amplitude was significantly higher on No-Go trials than Go trials, but only for supplemented children, resulting in a significant Group × Condition interaction. Topographical analysis of the ERPs revealed that the LCPUFA-supplemented group developed a novel period of synchronous activation (microstate) involving wider anterior brain activation around 200 ms; this microstate was not present in controls. These findings suggest that LCPUFA supplementation during the first 12 months of life exerts a developmental programming effect that is manifest in brain electrophysiology. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=oM2leg4sevs.

Effect of Poly Unsaturated Fatty Acids Administration on Children with Attention Deficit Hyperactivity Disorder: A Randomized Controlled Trial

INTRODUCTION

Attention Deficit Hyperactivity Disorder (ADHD) is a common disorder of childhood. Studies have indicated nutritional deficiencies, particularly Poly Unsaturated Fatty Acids (PUFA) deficiency in these children and have suggested supplementation with PUFA for clinical improvement.

AIM

The present study aimed at evaluating the effect of PUFA administration in Indian children with ADHD.

SETTINGS AND DESIGN

The study was conducted in the paediatrics and psychiatry departments of a tertiary care hospital. We conducted a prospective double blind randomized control trial on children aged 4-11 years, diagnosed with ADHD according to DSM-IV TR criterias and Kiddie-Schedule for Affective Disorders and Schizophrenia - Present and lifetime version.

MATERIALS AND METHODS

The study subjects were randomized into study and control groups. The control group was administered Atomoxetine, while the study group received Atomoxetine along with Eicosapentanoic acid (EPA) and Docosahexanoic acid (DHA). Both groups were followed up every 2 weeks over the next 4 months using Conner's Parent Rating Scale - Revised (CPRS-R).

STATISTICAL ANALYSIS

The data was carefully analysed by SPSS (17^th version) software with the help of a statistician. Confidence interval of 95% was used. The complete data was analysed using appropriate parametric and non parametric tests. Correlation was done between various socio-demographic and illness related parameters. For all analyses, probability of 5% or less was assumed to represent statistical significance.

RESULTS

Fifty children diagnosed with ADHD were randomized to study group (n=25) and control group (n=25). The study group had greater reduction in ADHD scores as compared to the control group, although not statistically significant (p = 0.08). Improvement was more significant in male study subjects with combined type of ADHD.

CONCLUSION

It may be concluded that PUFA supplementation improves the symptoms of ADHD. However, the effect is not clinically significant if supplementation is not given for prolonged duration and in adequate doses.

Nutrient intake and cerebral metabolism in healthy middle-aged adults: Implications for cognitive aging

OBJECTIVES

Growing evidence suggests dietary factors influence cognition, but the effects of nutrient intake on cerebral metabolism in adults are currently unknown. The present study investigated the relationship between major macronutrient intake (fat, carbohydrate, and protein) and cerebral neurochemical profiles in middle-aged adults.

METHODS

Thirty-six adults recorded dietary intake for 3 days prior to completing cognitive testing and a proton magnetic resonance spectroscopy (¹H-MRS) scan. ¹H-MRS of occipitoparietal gray matter was used to assess glutamate (Glu), N-acetyl-aspartate (NAA), choline (Cho), and myo-inositol (mI) relative to creatine (Cr) levels.

RESULTS

Regression analyses revealed that high intake of polyunsaturated fatty acids (PUFAs) was associated with lower cerebral Glu/Cr (P = 0.005), and high intake of saturated fat (SFA) was associated with poorer memory function (P = 0.030) independent of age, sex, education, estimated intelligence, total caloric intake, and body mass index.

DISCUSSION

In midlife, greater PUFA intake (ω-3 and ω-6) may be associated with lower cerebral glutamate, potentially indicating more efficient cellular reuptake of glutamate. SFA intake, on the other hand, was linked with poorer memory performance. These results suggest that dietary fat intake modification may be an important intervention target for the prevention of cognitive decline.

Meta-analysis of erythrocyte polyunsaturated fatty acid biostatus in bipolar disorder

OBJECTIVES

Dietary deficiency in polyunsaturated fatty acids (PUFAs), including the omega-3 fatty acids eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), and excesses in omega-6 fatty acids, including linoleic acid (LA; 18:2n-6) and arachidonic acid (AA; 20:4n-6), may be associated with the pathophysiology of bipolar disorder. In an effort to provide clarification regarding the relationship between PUFA biostatus and bipolar disorder, this meta-analysis investigated studies comparing erythrocyte (red blood cell) membrane PUFA composition in patients with bipolar disorder and healthy controls.

METHODS

A meta-analysis was performed on case-control studies comparing erythrocyte PUFA (EPA, DHA, LA and AA) levels in patients with bipolar I disorder and healthy controls. Standardized effect sizes were calculated and combined using a random effects model.

RESULTS

Six eligible case-control studies comprising n = 118 bipolar I patients and n = 147 healthy controls were included in the analysis. Compared with healthy controls, patients with bipolar I disorder exhibited robust erythrocyte DHA deficits (p = 0.0008) and there was a trend for lower EPA (p = 0.086). There were no significant differences in LA (p = 0.42) or AA (p = 0.64).

CONCLUSIONS

Bipolar I disorder is associated with robust erythrocyte DHA deficits. These findings add to a growing body of evidence implicating omega-3 PUFA deficiency in the pathophysiology of bipolar disorder.

Docosahexaenoic acid biostatus is associated with event-related functional connectivity in cortical attention networks of typically developing children

OBJECTIVE

Although extant preclinical evidence suggests that the long-chain omega-3 fatty acid docosahexaenoic acid (DHA) is important for neurodevelopment, little is known about its role in human cortical structural and functional maturation. In the present cross-sectional study, we investigated the relationship between DHA biostatus and functional connectivity in cortical attention networks of typically developing children.

METHODS

Male children (aged 8-10 years, n = 36) were divided into 'low-DHA' (n = 18) and 'high-DHA' (n = 18) biostatus groups by a median split of erythrocyte DHA levels. Event-related functional connectivity during the performance of a sustained attention task (identical pairs continuous performance task (CPT-IP)) was conducted using functional magnetic resonance imaging. A voxelwise approach used the anterior cingulate cortex (ACC) as the seed-region.

RESULTS

Erythrocyte DHA composition in the low-DHA group (2.6 ± 0.9%) was significantly lower than the high-DHA group (4.1 ± 1.1%, P ≤ 0.0001). Fish intake frequency was greater in the high-DHA group (P = 0.003) and was positively correlated with DHA levels among all subjects. The low-DHA group exhibited reduced functional connectivity between the ACC and the ventrolateral prefrontal cortex, insula, precuneus, superior parietal lobule, middle occipital gyrus, inferior temporal gyrus, and lingual gyrus compared with the high-DHA group (P < 0.05; corrected). The low-DHA group did not exhibit greater ACC functional connectivity with any region compared with the high-DHA group. On the CPT-IP task, the low-DHA group had slower reaction time (P = 0.03) which was inversely correlated with erythrocyte DHA among all subjects.

DISCUSSION

These data suggest that low-DHA biostatus is associated with reduced event-related functional connectivity in cortical attention networks of typically developing children.

Effects of fish oil supplementation on prefrontal metabolite concentrations in adolescents with major depressive disorder: a preliminary 1H MRS study

OBJECTIVE

To use proton magnetic resonance spectroscopy ((1)H MRS) to investigate the effects of fish oil (FO) supplementation on cortical metabolite concentrations in adolescents with major depressive disorder (MDD).

METHODS

Metabolite concentrations were determined by (1)H MRS in the anterior cingulate cortex and bilateral dorsolateral prefrontal cortex (DLPFC) of adolescents with MDD before and following 10-week open-label supplementation with low (2.4 g/day, n = 7) or high (16.2 g/day, n = 7) dose FO. Depressive symptom severity scores and erythrocyte fatty acid levels were also determined.

RESULTS

Baseline erythrocyte eicosapentaenoic acid (EPA) composition was positively correlated, and arachidonic acid (AA) and the AA/EPA ratio were inversely correlated, with choline (Cho) concentrations in the right DLPFC. Docosahexaenoic acid (DHA) composition was inversely correlated with myo-inositol (mI) concentrations in the left DLPFC. Erythrocyte EPA and DHA composition increased, and AA decreased, significantly following low-dose and high-dose FO supplementation. In the intent-to-treat sample, depressive symptom severity scores decreased significantly in the high-dose group (-40%, P < 0.0001) and there was a trend in the low-dose group (-20%, P = 0.06). There were no significant baseline-endpoint changes in metabolite levels in each voxel. In the low-dose group there were changes with large effect sizes, including a decrease in mI in the left DLPFC (-12%, P = 0.18, d = 0.8) and increases in glutamate + glutamine (Glx) (+12%, P = 0.19, d = 0.8) and Cho (+15%, P = 0.08, d = 1.2) in the right DLPFC. In the high-dose group, there was a trend for increases in Cho in the right DLPFC (+10%, P = 0.09, d = 1.2).

DISCUSSION

These preliminary data suggest that increasing the LCn-3 fatty acid status of adolescent MDD patients is associated with subtle changes in Glx, mI, and Cho concentrations in the DLPFC that warrant further evaluation in a larger controlled trial.

Effects of omega-3 polyunsaturated fatty acids on human brain morphology and function: What is the evidence?

Public opinion and media coverage suggest that there are benefits of long-chain ω-3 polyunsaturated fatty acid (LC-PUFA) intake on brain functioning. However, it is an open question whether this is indeed the case. Therefore, we reviewed the evidence for effects of ω-3 LC-PUFA on human brain morphology and function. We included studies on (1) naturalistic long-term ω-3 LC-PUFA intake during life (2) the effects of short-term ω-3 LC-PUFA supplementation in healthy subjects and (3) the effects of ω-3 LC-PUFA supplementation as alternative or add-on treatment for psychiatric or neurological disorders. To date, 24 studies have been published on the effect of ω-3 LC-PUFA on brain function and structure. Findings from naturalistic studies and clinical trials in healthy individuals indicate that ω-3 LC-PUFA intake may be associated with increased functional activation of the prefrontal cortex in children, and greater gray matter volume and white matter integrity during aging. However, most naturalistic studies were cross-sectional or did not find any effect on cognition. As such, it is hard to estimate the magnitude of any beneficial effects. Furthermore, there is only limited evidence to support that ω-3 LC-PUFA supplementation is beneficial in brain disorders, such as Alzheimer's Disease, Attention Deficit/Hyperactivity Disorder, Major Depressive Disorder and schizophrenia. Overall, the literature suggests that sensitivity to supplementation may vary over development, and as a consequence of brain disorders. The biological mechanisms underlying any (beneficial) effects ω-3 LC-PUFAs on the brain are currently unknown and need to be investigated.

Detection and treatment of omega-3 fatty acid deficiency in psychiatric practice: Rationale and implementation

A body of translational evidence has implicated dietary deficiency in long-chain omega-3 (LCn-3) fatty acids, including eicosapenaenoic acid (EPA) and docosahexaenoic acid (DHA), in the pathophysiology and potentially etiology of different psychiatric disorders. Case–control studies have consistently observed low erythrocyte (red blood cell) EPA and/or DHA levels in patients with major depressive disorder, bipolar disorder, schizophrenia, and attention deficit hyperactivity disorder. Low erythrocyte EPA + DHA biostatus can be treated with fish oil-based formulations containing preformed EPA + DHA, and extant evidence suggests that fish oil supplementation is safe and well-tolerated and may have therapeutic benefits. These and other data provide a rationale for screening for and treating LCn-3 fatty acid deficiency in patients with psychiatric illness. To this end, we have implemented a pilot program that routinely measures blood fatty acid levels in psychiatric patients entering a residential inpatient clinic. To date over 130 blood samples, primarily from patients with treatment-refractory mood or anxiety disorders, have been collected and analyzed. Our initial results indicate that the majority (75 %) of patients exhibit whole blood EPA + DHA levels at ≤4 percent of total fatty acid composition, a rate that is significantly higher than general population norms (25 %). In a sub-set of cases, corrective treatment with fish oil-based products has resulted in improvements in psychiatric symptoms without notable side effects. In view of the urgent need for improvements in conventional treatment algorithms, these preliminary findings provide important support for expanding this approach in routine psychiatric practice.

Reduced Symptoms of Inattention after Dietary Omega-3 Fatty Acid Supplementation in Boys with and without Attention Deficit/Hyperactivity Disorder

Attention deficit/hyperactivity disorder (ADHD) is one of the most common child psychiatric disorders, and is often treated with stimulant medication. Nonpharmacological treatments include dietary supplementation with omega-3 fatty acids, although their effectiveness remains to be shown conclusively. In this study, we investigated the effects of dietary omega-3 fatty acid supplementation on ADHD symptoms and cognitive control in young boys with and without ADHD. A total of 40 boys with ADHD, aged 8-14 years, and 39 matched, typically developing controls participated in a 16-week double-blind randomized placebo-controlled trial. Participants consumed 10 g of margarine daily, enriched with either 650 mg of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) each or placebo. Baseline and follow-up assessments addressed ADHD symptoms, fMRI of cognitive control, urine homovanillic acid, and cheek cell phospholipid sampling. EPA/DHA supplementation improved parent-rated attention in both children with ADHD and typically developing children. Phospholipid DHA level at follow-up was higher for children receiving EPA/DHA supplements than placebo. There was no effect of EPA/DHA supplementation on cognitive control or on fMRI measures of brain activity. This study shows that dietary supplementation with omega-3 fatty acids reduces symptoms of ADHD, both for individuals with ADHD and typically developing children. This effect does not appear to be mediated by cognitive control systems in the brain, as no effect of supplementation was found here. Nonetheless, this study offers support that omega-3 supplementation may be an effective augmentation for pharmacological treatments of ADHD (NCT01554462: The Effects of EPA/DHA Supplementation on Cognitive Control in Children with ADHD; http://clinicaltrials.gov/show/NCT01554462).

Anterior cingulate cortex mediates the relationship between O3PUFAs and executive functions in APOE e4 carriers

INTRODUCTION

Although diet has a substantial influence on the aging brain, the relationship between biomarkers of diet and aspects of brain health remains unclear. This study examines the neural mechanisms that mediate the relationship between omega-3 polyunsaturated fatty acids (O3PUFAs) and executive functions in at-risk (APOE e4 carriers), cognitively intact older adults. We hypothesized that higher levels of O3PUFAs are associated with better performance in a particular component of the executive functions, namely cognitive flexibility, and that this relationship is mediated by gray matter volume of a specific region thought to be important for cognitive flexibility, the anterior cingulate cortex.

METHODS

We examined 40 cognitively intact adults between the ages of 65 and 75 with the APOE e4 polymorphism to investigate the relationship between biomarkers of O3PUFAs, tests of cognitive flexibility (measured by the Delis-Kaplan Executive Function System Trail Making Test), and gray matter volume within regions of the prefrontal cortex (PFC).

RESULTS

A mediation analysis revealed that gray matter volume within the left rostral anterior cingulate cortex partially mediates the relationship between O3PUFA biomarkers and cognitive flexibility.

CONCLUSION

These results suggest that the anterior cingulate cortex acts as a mediator of the relationship between O3PUFAs and cognitive flexibility in cognitively intact adults thought to be at risk for cognitive decline. Through their link to executive functions and neuronal measures of PFC volume, O3PUFAs show potential as a nutritional therapy to prevent dysfunction in the aging brain.

ω-3 fatty acid supplementation as a potential therapeutic aid for the recovery from mild traumatic brain injury/concussion

Sports-related concussions or mild traumatic brain injuries (mTBIs) are becoming increasingly recognized as a major public health concern; however, no effective therapy for these injuries is currently available. ω-3 (n-3) fatty acids, such as docosahexaenoic acid (DHA), have important structural and functional roles in the brain, with established clinical benefits for supporting brain development and cognitive function throughout life. Consistent with these critical roles of DHA in the brain, accumulating evidence suggests that DHA may act as a promising recovery aid, or possibly as a prophylactic nutritional measure, for mTBI. Preclinical investigations demonstrate that dietary consumption of DHA provided either before or after mTBI improves functional outcomes, such as spatial learning and memory. Mechanistic investigations suggest that DHA influences multiple aspects of the pathologic molecular signaling cascade that occurs after mTBI. This review examines the evidence of interactions between DHA and concussion and discusses potential mechanisms by which DHA helps the brain to recover from injury. Additional clinical research in humans is needed to confirm the promising results reported in the preclinical literature.

Detection and Treatment of Long-Chain Omega-3 Fatty Acid Deficiency in Adolescents with SSRI-Resistant Major Depressive Disorder

Residual depressive symptoms are commonly observed in adolescents with major depressive disorder (MDD) following treatment with selective serotonin reuptake inhibitors (SSRIs). This study combined a case-control analysis and an open-label fish oil (FO) trial to investigate the relationship between long-chain omega-3 (LCn-3) fatty acid status and residual depressive symptoms in SSRI-resistant adolescent MDD patients. Baseline erythrocyte docosahexaenoic acid (DHA)(-28%, p=0.0003), but not eicosapentaenoic acid (EPA)(-18%, p=0.2), was significantly lower in patients (n=20) compared with healthy controls (n=20). Patients receiving 10-week low-dose (2.4 g/d, n=7) and high-dose (16.2 g/d, n=7) FO exhibited significant increases in erythrocyte EPA and DHA composition. In the intent-to-treat sample, depressive symptoms decreased significantly in the high-dose group (n=7, -40%, p<0.0001), and there was a trend in the low-dose group (n=10, -20%, p=0.06). Symptom remission was observed in 40% of patients in the low-dose group and 100% of patients in the high-dose group. There were no significant changes in vital signs and adverse events were rated as mild or moderate in severity. These preliminary findings demonstrate that adolescents with SSRI-resistant depression exhibit robust DHA deficits, and suggest that adjunctive FO supplementation is well-tolerated and effective for increasing LCn-3 fatty acid status and augmenting SSRI antidepressant effects.

Omega-3 supplementation improves cognition and modifies brain activation in young adults

OBJECTIVE

The current study aimed to investigate the effects of eicosapentaenoic acid (EPA)-rich and docosahexaenoic acid (DHA)-rich supplementations on cognitive performance and functional brain activation.

DESIGN

A double-blind, counterbalanced, crossover design, with a 30-day washout period between two supplementation periods (EPA-rich and DHA-rich) was employed. Functional magnetic resonance imaging scans were obtained during performance of Stroop and Spatial Working Memory tasks prior to supplementation and after each 30-day supplementation period.

RESULTS

Both supplementations resulted in reduced ratio of arachidonic acid to EPA levels. Following the EPA-rich supplementation, there was a reduction in functional activation in the left anterior cingulate cortex and an increase in activation in the right precentral gyrus coupled with a reduction in reaction times on the colour-word Stroop task. By contrast, the DHA-rich supplementation led to a significant increase in functional activation in the right precentral gyrus during the Stroop and Spatial Working Memory tasks, but there was no change in behavioural performance.

CONCLUSIONS

By extending the theory of neural efficiency to the within-subject neurocognitive effects of supplementation, we concluded that following the EPA-rich supplementation, participants' brains worked 'less hard' and achieved a better cognitive performance than prior to supplementation. Conversely, the increase in functional activation and lack of improvement in time or accuracy of cognitive performance following DHA-rich supplementation may indicate that DHA-rich supplementation is less effective than EPA-rich supplementation in enhancing neurocognitive functioning after a 30-day supplementation period in the same group of individuals.