Comments on Bozzatello et al. Supplementation with Omega-3 Fatty Acids in Psychiatric Disorders: A Review of Literature Data. J. Clin. Med. 2016, 5, 67

Effects of Omega 3 Fatty Acids on Main Dimensions of Psychopathology

The usefulness of polyunsaturated fatty acids on inflammatory, cardiovascular, and the nervous system was studied in the last decades, but the mechanisms underlying their benefic properties are still partially unknown. These agents seem to express their action on the membrane phospholipid composition and permeability and modulation of second messenger cascades. In psychiatry, the efficacy and tolerability of omega-3 fatty acids were investigated in several psychiatric disorders, including major depression, bipolar disorder, personality disorders, high-risk conditions to develop psychosis, attention-deficit hyperactivity disorder, and autism spectrum disorders. Initial findings in this field are promising, and some relevant questions need to be addressed. In particular, the effects of these agents on the main symptom dimensions have to be investigated in a trans-diagnostic perspective. The present systematic review is aimed to examine the available data on the efficacy of omega-3 fatty acids on domains of psychotic symptoms, affective symptoms, impulsivity, and aggressiveness, and harmful behaviors, and suicide risk.

Equity, acceptability and feasibility of using polyunsaturated fatty acids in children and adolescents with autism spectrum disorder: a rapid systematic review

INTRODUCTION

Some recent randomized controlled trials (RCTs) assessed the efficacy and safety of polyunsaturated fatty acids (PUFAs) for the treatment of autism spectrum disorder (ASD). To optimally inform the Italian guideline for the management of ASD in children and adolescents, we reviewed the impact on equity, acceptability and feasibility for developing a pilot recommendation for PUFAs.

METHODS

We performed a rapid systematic review of observational and experimental studies on PUFAs for children and adolescents with ASD, extracting data on resources required, equity, acceptability, and feasibility of PUFAs. We followed the framework provided by the grading of recommendations assessment, development and evaluation (GRADE) methodology, and we assessed risk of bias and methodological quality of included studies. Results were synthesized both narratively and quantitatively to address clinically relevant questions on equity, acceptability, and feasibility.

RESULTS

We found 14 papers related to equity. PUFAs did not seem to impact equity importantly. We did not find variation in effectiveness across subgroups and in a base case scenario, the cost of a 12 weeks cycle of therapy with 1.155 g/day of PUFAs was €65.51 euro. The acceptability of PUFAs was evaluated in 17 studies, 9 of which were RCTs. PUFAs were widely used among children and adolescents with ASD (18 to 51%), and 50% of parents considered nutritional supplementation as useful. Difficulty in swallowing capsules and bad taste were identified as possible causes of poor compliance, but treatment adherence, when measured in included RCTs, was judged to be good to excellent. Discontinuation due to any cause for PUFAs could not differ from placebo (low certainty of evidence). The feasibility of using PUFAs was assessed in 12 studies. PUFAs were probably sustainable, and no particular critical issue emerged from the feasibility assessment. However, the evidence appeared scarce and indirect.

CONCLUSIONS

We found the administration of PUFAs in children and adolescents with ASD to be potentially equitable, acceptable and feasible. These results are limited by the limited number and quality of retrieved documents, and need to be viewed in light of efficacy and safety data to formulate clinical recommendations.

Combination of Omega-3 Fatty Acids and Valproic Acid in Treatment of Borderline Personality Disorder: A Follow-Up Study

BACKGROUND AND OBJECTIVES

Some evidence of efficacy has been found for omega-3 fatty acids in patients with borderline personality disorder (BPD). In a previous 12-week randomized trial we assessed the efficacy of the combination of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) with valproic acid, in comparison with valproic acid monotherapy, in 43 BPD outpatients. Combined therapy was superior to valproic acid monotherapy (the control group) in the treatment of some BPD symptoms: impulsive-behavioral dyscontrol, outbursts of anger, and self-harm. The present study is a 24-week follow-up aimed at evaluating whether the differences in efficacy between the two subgroups were maintained after discontinuation of omega-3 fatty acids.

METHODS

Thirty-four patients who completed the 12-week trial entered the follow-up study. Participants were evaluated at the beginning and at the end of the follow-up period using the rating scales that showed a significant difference between the groups after the 12-week trial with fatty acids supplementation: the Borderline Personality Disorder Severity Index (BPDSI) (items 'impulsivity' and 'outbursts of anger'), Barratt Impulsiveness Scale-Version 11 (BIS-11), and Self Harm Inventory (SHI). Statistical analysis was performed with analysis of variance (ANOVA) for repeated measures.

RESULTS

At the end of the follow-up a significant difference within groups was maintained for all four variables examined, while a significant difference between groups was maintained for outbursts of anger. Concerning tolerability, no clinically significant adverse effects were registered during the follow-up period.

CONCLUSIONS

Combined therapy with omega-3 fatty acids showed long-lasting effects after discontinuation in terms of anger control.

TRIAL REGISTRATION

The trial was registered in the Australian New Zealand Clinical Trials Registry (ANZCTR) and allocated the code: ACTRN12612001150831.

Focus on fatty acids in the neurometabolic pathophysiology of psychiatric disorders

Continuous research into the pathophysiology of psychiatric disorders, such as major depressive disorder (MDD), posttraumatic stress disorder (PTSD), and schizophrenia, suggests an important role for metabolism. This narrative review will provide an up-to-date summary of how metabolism is thought to be involved in the pathophysiology of these psychiatric disorders. We will focus on (I) the important role of fatty acids in these metabolic alterations, (II) whether fatty acid alterations represent epiphenomena or risk factors, and (III) similarities and dissociations in fatty acid alterations between different psychiatric disorders. (Historical) epidemiological evidence links fatty acid intake to psychiatric disorder prevalence, corroborated by altered fatty acid concentrations measured in psychiatric patients. These fatty acid alterations are connected with other concomitant pathophysiological mechanisms, including biological stress (hypothalamic-pituitary-adrenal (HPA)-axis and oxidative stress), inflammation, and brain network structure and function. Metabolomics and lipidomics studies are underway to more deeply investigate this complex network of associated neurometabolic alterations. Supplementation of fatty acids as disease-modifying nutraceuticals has clinical potential, particularly add-on eicosapentaenoic acid (EPA) in depressed patients with markers of increased inflammation. However, by interpreting the observed fatty acid alterations as partly (mal)adaptive phenomena, we attempt to nuance translational expectations and provide new clinical applications for these novel neurometabolic insights, e.g., to predict treatment response or depression recurrence. In conclusion, placing fatty acids in context can contribute to further understanding and optimized treatment of psychiatric disorders, in order to diminish their overwhelming burden of disease.

Impact of diet-derived signaling molecules on human cognition: exploring the food-brain axis

The processes that define mammalian physiology evolved millions of years ago in response to ancient signaling molecules, most of which were acquired by ingestion and digestion. In this way, evolution inextricably linked diet to all major physiological systems including the nervous system. The importance of diet in neurological development is well documented, although the mechanisms by which diet-derived signaling molecules (DSMs) affect cognition are poorly understood. Studies on the positive impact of nutritive and non-nutritive bioactive molecules on brain function are encouraging but lack the statistical power needed to demonstrate strong positive associations. Establishing associations between DSMs and cognitive functions like mood, memory and learning are made even more difficult by the lack of robust phenotypic markers that can be used to accurately and reproducibly measure the effects of DSMs. Lastly, it is now apparent that processes like neurogenesis and neuroplasticity are embedded within layers of interlocked signaling pathways and gene regulatory networks. Within these interdependent pathways and networks, the various transducers of DSMs are used combinatorially to produce those emergent adaptive gene expression responses needed for stimulus-induced neurogenesis and neuroplasticity. Taken together, it appears that cognition is encoded genomically and modified by epigenetics and epitranscriptomics to produce complex transcriptional programs that are exquisitely sensitive to signaling molecules from the environment. Models for how DSMs mediate the interplay between the environment and various neuronal processes are discussed in the context of the food-brain axis.

The effect of school meals with fatty fish on adolescents' self-reported symptoms for mental health: FINS-TEENS - a randomized controlled intervention trial

There is a growing body of evidence linking fish consumption and n-3 LCPUFAs to mental health. Still, the results from randomized trials with n-3 LCPUFAs show conflicting results, and it is possible that the combined effect of several nutrients in fish may explain the observed associations. To aim of the present study was to investigate if school meals with fatty fish three times per week for 12 weeks could alter mental health in a sample of typically developing adolescents. In the Fish Intervention Studies-TEENS (FINS-TEENS), adolescents from eight secondary schools (n=425) in Norway, were randomized to receive school meals with fatty fish, meat or n-3 LCPUFA supplements. Mental health was assessed with the Strengths and Difficulties Questionnaire (SDQ) and the differences between the groups were assessed with linear mixed effect models, unadjusted and adjusted for baseline and dietary compliance. The results showed no effects of school meals with fatty fish compared to similar meals with meat or n-3 LCPUFAs on the adolescents' self-reported symptom scores for mental health. Among adolescents scoring above the SDQ cut-offs (high-scorers), the fish- improved less than the meat group in the self-reported symptom scores for total difficulties- and emotional problems. However, the findings should be regarded as preliminary, as the analyses for the high-scorer group were underpowered. In conclusion, serving school meals with fatty fish did not alter mental health in a typically developing sample of adolescents. It is possible that serving healthy school meals with meat is more beneficial than similar meals with fatty fish in adolescents scoring high on mental health problems. However, the results should be seen as preliminary, as the dietary compliance in the fish group was low and the analyses in the high score group underpowered. Thus, further studies should investigate the associations between fish consumption and adolescents' mental health.

Polyunsaturated fatty acid deficiency during neurodevelopment in mice models the prodromal state of schizophrenia through epigenetic changes in nuclear receptor genes

The risk of schizophrenia is increased in offspring whose mothers experience malnutrition during pregnancy. Polyunsaturated fatty acids (PUFAs) are dietary components that are crucial for the structural and functional integrity of neural cells, and PUFA deficiency has been shown to be a risk factor for schizophrenia. Here, we show that gestational and early postnatal dietary deprivation of two PUFAs-arachidonic acid (AA) and docosahexaenoic acid (DHA)-elicited schizophrenia-like phenotypes in mouse offspring at adulthood. In the PUFA-deprived mouse group, we observed lower motivation and higher sensitivity to a hallucinogenic drug resembling the prodromal symptoms in schizophrenia. Furthermore, a working-memory task-evoked hyper-neuronal activity in the medial prefrontal cortex was also observed, along with the downregulation of genes in the prefrontal cortex involved in oligodendrocyte integrity and the gamma-aminobutyric acid (GABA)-ergic system. Regulation of these genes was mediated by the nuclear receptor genes Rxr and Ppar, whose promoters were hyper-methylated by the deprivation of dietary AA and DHA. In addition, the RXR agonist bexarotene upregulated oligodendrocyte- and GABA-related gene expression and suppressed the sensitivity of mice to the hallucinogenic drug. Notably, the expression of these nuclear receptor genes were also downregulated in hair-follicle cells from schizophrenia patients. These results suggest that PUFA deficiency during the early neurodevelopmental period in mice could model the prodromal state of schizophrenia through changes in the epigenetic regulation of nuclear receptor genes.

Specific behavioral and cellular adaptations induced by chronic morphine are reduced by dietary omega-3 polyunsaturated fatty acids

Opiates, one of the oldest known drugs, are the benchmark for treating pain. Regular opioid exposure also induces euphoria making these compounds addictive and often misused, as shown by the current epidemic of opioid abuse and overdose mortalities. In addition to the effect of opioids on their cognate receptors and signaling cascades, these compounds also induce multiple adaptations at cellular and behavioral levels. As omega-3 polyunsaturated fatty acids (n-3 PUFAs) play a ubiquitous role in behavioral and cellular processes, we proposed that supplemental n-3 PUFAs, enriched in docosahexanoic acid (DHA), could offset these adaptations following chronic opioid exposure. We used an 8 week regimen of n-3 PUFA supplementation followed by 8 days of morphine in the presence of this diet. We first assessed the effect of morphine in different behavioral measures and found that morphine increased anxiety and reduced wheel-running behavior. These effects were reduced by dietary n-3 PUFAs without affecting morphine-induced analgesia or hyperlocomotion, known effects of this opiate acting at mu opioid receptors. At the cellular level we found that morphine reduced striatal DHA content and that this was reversed by supplemental n-3 PUFAs. Chronic morphine also increased glutamatergic plasticity and the proportion of Grin2B-NMDARs in striatal projection neurons. This effect was similarly reversed by supplemental n-3 PUFAs. Gene analysis showed that supplemental PUFAs offset the effect of morphine on genes found in neurons of the dopamine receptor 2 (D2)-enriched indirect pathway but not of genes found in dopamine receptor 1(D1)-enriched direct-pathway neurons. Analysis of the D2 striatal connectome by a retrogradely transported pseudorabies virus showed that n-3 PUFA supplementation reversed the effect of chronic morphine on the innervation of D2 neurons by the dorsomedial prefontal and piriform cortices. Together these changes outline specific behavioral and cellular effects of morphine that can be reduced or reversed by dietary n-3 PUFAs.