Effects of Omega-3 in the treatment of violent schizophrenia patients

Nutrition and schizophrenia: associations worthy of continued revaluation

BACKGROUND

Accumulating evidence have shown that diet and nutrition play significant roles in mental illness, such as depression, anxiety and bipolar disorder. However, comprehensive evaluation of the relationship between nutrition and schizophrenia is lacking.

OBJECTIVE

The present review aims to synthetic elaborate the associations between nutrition and schizophrenia. Relevant studies on dietary patterns, macronutrients, micronutrients were performed through a literature search to synthesize the extracted data.

SUMMARY

Dietary interventions may help prevent the occurrence of schizophrenia, or delay symptoms: Healthy diets like nutritious plant-based foods and high-quality protein, have been linked to reducing the risk or symptoms of schizophrenia. Moreover, diet high in saturated fat and sugar is linked to more serious outcomes of schizophrenia. Additionally, when N-acetylcysteine acts as an adjuvant therapy, the overall symptoms of schizophrenia are significantly reduced. Also nascent evidence showed mental disorders may be related to intestinal microbiota dysfunction. Our study offered important insights into the dietary habits of patients with schizophrenia and the potential impact of nutritional factors on the disease. We also emphasized the need for further research, particularly in the form of large randomized double-blind controlled trials, to better understand the effects of nutrients on schizophrenia symptoms in different populations and disease types.

Nutraceuticals in Psychiatric Disorders: A Systematic Review

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

Nutritional factors associated with aggression

Although the vast majority of patients in forensic psychiatry are treated using pharmacological agents, clinical and ethical concerns about their use have led to the consideration of alternative strategies to reduce aggression that is common in forensic psychiatric settings. One non-invasive and benign biologically-based treatment approach involves nutrition. This article provides a mini-review of the recent evidence on four salient nutritional factors associated with aggressive behavior, namely omega-3 fatty acids, vitamin D, magnesium, and zinc. The current evidence base indicates that lower omega-3 levels are associated with increased aggression. Although research on vitamin D and zinc in relation to aggressive behavior is more limited, there is initial evidence that they are negatively associated with aggression in healthy participants and in psychiatric samples. The relationship between magnesium and aggression varies depending on how magnesium is assessed. Findings from experimental trials reveal that nutritional intervention in the form of omega-3 supplementation has the potential to serve as an effective mode of treatment, with effects that can last beyond the intervention period. There is also support for the utility of nutrition to improve our understanding of how social processes are linked to aggression. In light of the nascent, but promising findings on the role of nutritional factors on aggressive behavior, directions for future research are discussed.

Is It Time for a Paradigm Shift in the Treatment of Schizophrenia? The Use of Inflammation-Reducing and Neuroprotective Drugs-A Review

Comprehending the pathogenesis of schizophrenia represents a challenge for global mental health. To date, although it is evident that alterations in dopaminergic, serotonergic, and glutamatergic neurotransmission underlie the clinical expressiveness of the disease, neuronal disconnections represent only an epiphenomenon. In recent years, several clinical studies have converged on the hypothesis of microglia hyperactivation and a consequent neuroinflammatory state as a pathogenic substrate of schizophrenia. Prenatal, perinatal, and postnatal factors can cause microglia to switch from M2 anti-inflammatory to M1 pro-inflammatory states. A continuous mild neuroinflammatory state progressively leads to neuronal loss, a reduction in dendritic spines, and myelin degeneration. The augmentation of drugs that reduce neuroinflammation to antipsychotics could be an effective therapeutic modality in managing schizophrenia. This review will consider studies in which drugs with anti-inflammatory and neuroprotective properties have been used in addition to antipsychotic treatment in patients with schizophrenia.

Dietary intake of α-ketoglutarate ameliorates α-synuclein pathology in mouse models of Parkinson's disease

Parkinson's disease (PD) is a progressive movement disorder characterized by dopaminergic (DA) neuron degeneration and the existence of Lewy bodies formed by misfolded α-synuclein. Emerging evidence supports the benefits of dietary interventions in PD due to their safety and practicality. Previously, dietary intake of α-ketoglutarate (AKG) was proved to extend the lifespan of various species and protect mice from frailty. However, the mechanism of dietary AKG's effects in PD remains undetermined. In the present study, we report that an AKG-based diet significantly ameliorated α-synuclein pathology, and rescued DA neuron degeneration and impaired DA synapses in adeno-associated virus (AAV)-loaded human α-synuclein mice and transgenic A53T α-synuclein (A53T α-Syn) mice. Moreover, AKG diet increased nigral docosahexaenoic acid (DHA) levels and DHA supplementation reproduced the anti-α-synuclein effects in the PD mouse model. Our study reveals that AKG and DHA induced microglia to phagocytose and degrade α-synuclein via promoting C1q and suppressed pro-inflammatory reactions. Furthermore, results indicate that modulating gut polyunsaturated fatty acid metabolism and microbiota Lachnospiraceae_NK4A136_group in the gut-brain axis may underlie AKG's benefits in treating α-synucleinopathy in mice. Together, our findings propose that dietary intake of AKG is a feasible and promising therapeutic approach for PD.

Effects of Fish-Oil Consumption on Psychological Function Outcomes in Psychosis: A Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials

Research on the effects of fish oil on clinical symptoms and psychosocial functioning in people with psychosis has been inconsistent. We conducted this systematic review and meta-analysis to summarize the available data on the effects of oral intake of fish oil on psychological functioning in patients with psychosis. Three online databases including PubMed, Scopus, and Web of Science were searched to identify relevant studies published by April 2021. The exposure was oral fish-oil supplementation. The Positive and Negative Syndrome Scale (PANSS), the Brief Psychiatric Rating Scale (BPRS), and the Global Assessment of Functioning (GAF) were our outcome measures. Seventeen randomized clinical trials involving 1390 patients were included. No change in PANSS was observed following oral fish-oil intake [weighted mean difference (WMD): -0.87; 95% CI: -16.99, 15.26; P = 0.92]. In a nonlinear dose-response analysis, a significant inverse association was observed between <10 wk of fish-oil supplementation and PANSS (WMD: -10; P-nonlinearity = 0.02). Although analysis of 4 studies showed a nonsignificant reduction in BPRS after fish-oil intake (WMD: -2.990; 95% CI: -6.42, 0.44; P = 0.08), a nonlinear dose-response analysis revealed significant inverse associations between dose (>2200 mg/d) and duration of fish-oil supplementation (<15 wk) with BPRS score (WMD: -8; P-nonlinearity = 0.04). Combined effect sizes from 6 randomized clinical trials showed significant increases in GAF after oral administration of fish oil (WMD: 6.66; 95% CI: 3.39, 9.93; P < 0.001). In conclusion, we did not find any significant changes in PANSS and BPRS scores following fish-oil supplementation. Nevertheless, oral fish-oil intake significantly contributed to improvement in GAF scores. This is the first meta-analysis to examine the effects of fish oil on the psychological functioning scores of PANSS, BPRS, and GAF simultaneously.

Mitochondrial dysfunction in psychiatric disorders

Psychiatric disorders are a heterogeneous group of mental disorders with abnormal mental or behavioral patterns, which severely distress or disable affected individuals and can have a grave socioeconomic burden. Growing evidence indicates that mitochondrial function plays an important role in developing psychiatric disorders. This review discusses the neuropsychiatric consequences of mitochondrial abnormalities in both animal models and patients. We also discuss recent studies associated with compromised mitochondrial function in various psychiatric disorders, such as schizophrenia (SCZ), major depressive disorder (MD), and bipolar disorders (BD). These studies employ various approaches including postmortem studies, imaging studies, genetic studies, and induced pluripotent stem cells (iPSCs) studies. We also summarize the evidence from animal models and clinical trials to support mitochondrial function as a potential therapeutic target to treat various psychiatric disorders. This review will contribute to furthering our understanding of the metabolic etiology of various psychiatric disorders, and help guide the development of optimal therapies.

The efficacy of nutritional supplements for the adjunctive treatment of schizophrenia in adults: A systematic review and network meta-analysis

Nutritional supplementations have been widely used as adjunctive treatments for schizophrenia. However, among these supplementations, of which the most beneficial is currently unknown. This study aimed to compare and rank the effectiveness of nutritional supplementations in the adjunctive treatments of schizophrenia. The four nutritional supplementations evaluated were: 1) folate acid or vitamin B12; 2) vitamin D; 3) N-acetyl cysteine (NAC); 4) Omega-3 polyunsaturated fatty acid, including docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). 17 eligible RCTs with 1165 participants were included in this network meta-analysis based on study criteria. NAC supplementation was significantly more efficacious than folic acid or vitamin B12 [MD (95% CI): -6.6 (-10.8, -2.4)] and omega-3 polyunsaturated fatty acid [MD (95% CI): -5.1(-9.9, -0.8)] supplementation in the term of PANSS score changes. There were no significant differences in the PANSS score changes between NAC and vitamin D [MD (95% CI): -5.2 (-10.9, 0.5)] supplementations. The estimated ranking probabilities of treatments showed that NAC might be the most effective adjunctive intervention over all nutritional supplementations. These results indicate that NAC could improve PANSS score and it may be among the most effective nutritional supplementations in schizophrenia patients.

Nutritional supplementation in the treatment of violent and aggressive behavior: A systematic review

Aggression in correctional and psychiatric settings is relatively common and has a negative effect on physical and mental health both among inmates/clients and staff, as well as organizational-level functioning. The aim of the present study was to critically review the evidence on the effectiveness of nutritional supplements in reducing aggression and violence to contribute to a better understanding of options available for managing aggressive behaviors in adults. The EMBASE, MEDLINE, PsycINFO, Cochrane Library, and PubMed databases were searched for effectiveness studies published in English anytime up until March 2020. Study quality was assessed using the Mixed Methods Appraisal Tool. Altogether, 14 studies met inclusion criteria; 2 investigated micronutrients, 10 examined macronutrients, while further 2 examined a combination of micro and macronutrients. Out of the 14 studies, 5 reported a beneficial effect of nutritional supplementation (omega-3 fatty acids, vitamins/minerals, S-adenosyl-l-methionine, or tryptophan). Five studies did not report a significant beneficial effect of nutritional supplementation (omega-3 fatty acids, folic acid, tryptophan, broad range supplement containing vitamins and fatty acids, and fatty acids in augmentation with valproic acid), while four studies reported mixed effects (on l-tryptophan, broad-range micronutrient formula, folic acid, and omega-3 fatty acids). The results overall indicated that research in this area is in its infancy: very few studies examined the same composition of nutritional supplementation and when they did so the results were contradictory. The methodological shortcoming of existing studies and directions for future research are discussed to facilitate high-quality research in this evolving area of nutritional psychiatry.

Disentangling the Molecular Mechanisms of the Antidepressant Activity of Omega-3 Polyunsaturated Fatty Acid: A Comprehensive Review of the Literature

Major depressive disorders (MDDs) are often associated with a deficiency in long-chain omega-3 polyunsaturated fatty acids (ω-3 PUFAs), as well as signs of low-grade inflammation. Epidemiological and dietary studies suggest that a high intake of fish, the major source of ω-3 PUFAs, is associated with lower rates of MDDs. Meta-analyses of randomized placebo-controlled ω-3 PUFAs intervention-trials suggest that primarily eicosapentaenoic acid (EPA), but not docosahexaenoic acid (DHA), is responsible for the proposed antidepressant effect. In this review, we dissect the current biological knowledge on EPA and DHA and their bioactive lipid metabolites to search for a pharmacological explanation of this, to date, unexplained clinical observation. Through enzymatic conversion by cyclooxygenase (COX), lipoxygenase (ALOX), and cytochrome P-450 monooxygenase (CYP), EPA and DHA are metabolized to major anti-inflammatory and pro-resolving lipid mediators. In addition, both ω-3 PUFAs are precursors for endocannabinoids, with known effects on immunomodulation, neuroinflammation, food intake and mood. Finally, both ω-3 PUFAs are crucial for the structure and organization of membranes and lipid rafts. While most biological effects are shared by these two ω-3 PUFAs, some distinct features could be identified: (1) The preferential CYP monooxygenase pathway for EPA and EPA derived eicosanoids; (2) The high CB2 receptor affinities of EPA-derived EPEA and its epoxy-metabolite 17,18-EEQ-EA, while the DHA-derived endocannabinoids lack such receptor affinities; (3) The competition of EPA but not DHA with arachidonic acid (AA) for particular glycerophospholipids. EPA and AA are preferentially incorporated into phosphatidylinositols, while DHA is mainly incorporated into phosphatidyl-ethanolamine, -serine and -choline. We propose that these distinct features may explain the superior antidepressant activity of EPA rich ω-3 PUFAs and that these are potential novel targets for future antidepressant drugs.

Effects of omega-3 polyunsaturated fatty acids supplements on psychopathology and metabolic parameters in schizophrenia: A meta-analysis of randomized controlled trials

BACKGROUND

Several monotherapy and augmentation strategies have been introduced to improve the treatment of schizophrenia. The benefits of omega-3 polyunsaturated fatty acids in patients with mental disorders is becoming increasingly acknowledged. However, its role in the treatment of schizophrenia raises complex considerations about which there has been little consensus. The aim of this study was to synthesize the findings of randomized controlled trials that were conducted to determine the efficacy and safety of omega-3 polyunsaturated fatty acids in patients with schizophrenia.

METHODS

The MEDLINE, Embase, Cochrane, Scopus, and Web of Science databases were searched for relevant literature. The primary outcome was changes in psychopathology and the secondary outcomes were changes in metabolic parameters and safety profiles.

RESULTS

Twenty double-blind randomized controlled trials in 1494 patients were included. Omega-3 polyunsaturated fatty acids augmentation was associated with significantly improved psychopathology in patients with schizophrenia, particularly general psychopathology and positive symptoms but not negative symptoms. Patients who were severely ill and received omega-3 polyunsaturated fatty acids containing eicosapentaenoic acid >1 g/d showed significant improvement. A favorable effect of omega-3 polyunsaturated fatty acids supplements on serum triglycerides was also demonstrated. Omega-3 polyunsaturated fatty acids are well-tolerated and safe in patients with schizophrenia.

CONCLUSIONS

These findings tentatively support the use of omega-3 polyunsaturated fatty acids as a potential augmentation strategy in schizophrenia. Further research in larger samples is warranted to clarify the optimal dosage and the correct proportions of omega-3 polyunsaturated fatty acids to administer, together with elucidation of the underlying mechanisms.

Microalgae n-3 PUFAs Production and Use in Food and Feed Industries

N-3 polyunsaturated fatty acids (n-3 PUFAs), and especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential compounds for human health. They have been proven to act positively on a panel of diseases and have interesting anti-oxidative, anti-inflammatory or anti-cancer properties. For these reasons, they are receiving more and more attention in recent years, especially future food or feed development. EPA and DHA come mainly from marine sources like fish or seaweed. Unfortunately, due to global warming, these compounds are becoming scarce for humans because of overfishing and stock reduction. Although increasing in recent years, aquaculture appears insufficient to meet the increasing requirements of these healthy molecules for humans. One alternative resides in the cultivation of microalgae, the initial producers of EPA and DHA. They are also rich in biochemicals with interesting properties. After defining macro and microalgae, this review synthesizes the current knowledge on n-3 PUFAs regarding health benefits and the challenges surrounding their supply within the environmental context. Microalgae n-3 PUFA production is examined and its synthesis pathways are discussed. Finally, the use of EPA and DHA in food and feed is investigated. This work aims to define better the issues surrounding n-3 PUFA production and supply and the potential of microalgae as a sustainable source of compounds to enhance the food and feed of the future.

Efficacy of Polyunsaturated Fatty Acids (PUFAs) on Impulsive Behaviours and Aggressiveness in Psychiatric Disorders

It is the focus of increasing interest to investigate the effects of long-chain n-3 and long-chain n-6 polyunsaturated fatty acids (LC n-3 PUFAs; LC n-6 PUFAs) on psychiatric symptoms in a transdiagnostic perspective. There is some evidence that low levels of LC n-3 PUFAs and a higher ratio of LC n-6 to LC n-3 PUFAs in plasma and blood cells are associated with aggressive and impulsive behaviours. Therefore, implementation of LC n-3 PUFAs may produce positive effects on hostility, aggression, and impulsivity in both psychiatric and non-psychiatric samples across different stages of life. A possible mechanism of action of LC n-3 PUFAs in conditions characterized by a high level of impulsivity and aggression is due to the effect of these compounds on the serotonin system and membrane stability. Studies that evaluated the effects of LC n-3 PUFAs on impulsivity and aggressiveness indicated that addition of rather low doses of these agents to antipsychotic treatment might reduce agitation and violent behaviours in psychosis, attention deficit hyperactivity disorder, personality disorders, and impulsive control and conduct disorders. The present review is aimed at examining and discussing available data from recent trials on this topic.

Efficacy and safety of anti-inflammatory agents in treatment of psychotic disorders - A comprehensive systematic review and meta-analysis

OBJECTIVE

Antipsychotic effects of immunomodulating drugs have been suggested; however, a thorough, comprehensive meta-analysis on the effect and safety of anti-inflammatory add-on treatment on psychotic disorders is lacking.

METHOD

Multiple databases were searched up until February 2020. Only double-blinded, randomized, placebo-controlled clinical trials (RCTs) were included. Primary outcomes were change in total psychopathology and adverse events. Secondary outcomes included, amongst others, positive and negative symptoms, general psychopathology and cognitive domains. We performed random-effects meta-analyses estimating mean differences (MD) and standardized mean differences (SMD) for effect sizes.

RESULTS

Seventy RCTs (N = 4104) were included, investigating either primarily anti-inflammatory drugs, i.e. drugs developed for immunomodulation, such as NSAIDs, minocycline and monoclonal antibodies (k = 15), or drugs with potential anti-inflammatory properties (k = 55), e.g. neurosteroids, N-acetyl cysteine, estrogens, fatty acids, statins, and glitazones. Antipsychotics plus anti-inflammatory treatment, compared to antipsychotics plus placebo, was associated with a PANSS scale MD improvement of -4.57 (95%CI = -5.93 to -3.20) points, corresponding to a SMD effect size of -0.29 (95%CI = -0.40 to -0.19). Trials on schizophrenia (MD = -6.80; 95%CI, -9.08 to -4.52) showed greater improvement (p < 0.01) than trials also including other psychotic disorders. However, primarily anti-inflammatory drugs (MD = 4.00; 95%CI = -7.19 to -0.80) were not superior (p = 0.69) to potential anti-inflammatory drugs (MD = 4.71; 95%CI = -6.26 to -3.17). Furthermore, meta-regression found that smaller studies showed significantly larger effect sizes than the larger studies (p = 0.0085), and only 2 studies had low risk of bias on all domains. Small but significant effects were found on negative symptoms (MD = -1.29), positive symptoms (MD = -0.53), general psychopathology (MD = -1.50) and working memory (SMD = 0.21). No differences were found regarding adverse events, but only 26 studies reported hereon.

CONCLUSIONS

Anti-inflammatory add-on treatment to antipsychotics showed improvement of psychotic disorders; however, no superiority was found in primarily anti-inflammatory drugs, raising the question of the mechanism behind the effect, and treatment effect might be overestimated due to the large number of small studies.

The Effect of Dietary Supplementation on Aggressive Behaviour in Australian Adult Male Prisoners: A Feasibility and Pilot Study for a Randomised, Double Blind Placebo Controlled Trial

This study aimed to assess the feasibility of conducting a nutrition trial in adult male prisoners. Adult male prisoners were recruited for a 16-week randomised control trial comparing the effect of ingestion of omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) and multivitamin supplements versus placebo on aggressive behaviour. The baseline and post-intervention assessments from the participant blood samples were the erythrocyte n-3 LCPUFA levels as well as measures of aggressive behaviour determined through institutional records of misconduct (IRM), the Inmate Behaviour Observation Scale (IBOS), and questionnaires. A total of 136 adult male prisoners consented to the study with a retention rate of 60%, and 93% of blood samples were successfully collected. The IRM and IBOS scores were collected for 100% of participants, whilst 82–97% of participants completed the questionnaires. From the baseline data, the Odds Ratio shows that prisoners are 4.3 times more likely to have an IBOS >2 if they are below the 6% cut off on the omega-3 index. Both groups improved across all outcome measures and, at the current sample size, no significant differences were seen between them. A power calculation suggests a total sample size of 600 participants is required to detect the effects of this dietary supplementation, and that this supplementation study is feasible in a Correctional Centre. Important criteria for the exclusion and consideration of logistics and compliance are presented.

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.

Omega-3 fatty acids ameliorate cognitive dysfunction in schizophrenia patients with metabolic syndrome

Our previous study showed that metabolic abnormalities reduced the levels of brain-derived neurotrophic factor (BDNF) and deteriorated cognitive performance in patients with schizophrenia. Inflammation may play a key role in this process. Omega-3 fatty acids have been documented to ameliorate inflammation. Therefore, we hypothesized that omega-3 fatty acids may be of value in enhancing BDNF levels and improving cognitive function in patients with schizophrenia with metabolic syndrome (MetS). We recruited 80 patients with both schizophrenia and MetS who received long-term olanzapine monotherapy. The enzyme-linked immunosorbent assay was used to measure the plasma levels of C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). The patients were randomly assigned to the OMG-3 group (n = 40) or the placebo group (n = 40). Of the 80 patients who consented to the study, 72 completed this 12-week RCT. The primary outcome was the changes from baseline to 12 weeks in clinical characteristics and the levels of BDNF, CRP, IL-6 and TNF-α. There was a significant correlation between omega-3 fatty acid treatment and enhanced delayed memory factor in the RBANS assessment (F_group×time = 6.82; df = 1, 66; P = 0.01) when the patients completed this study. Along with cognitive improvement, omega-3 fatty acids enhanced BDNF (F_group×time = 4.93; df = 1, 66; P = 0.03) and reduced CRP (F_group×time = 17.11; df = 1, 66; P < 0.01), IL-6 (F_group×time = 9.71; df = 1, 66; P < 0.004) and TNF-α (F_group×time = 6.71; df = 1, 66; P = 0.012) levels after 12 weeks of treatment. The changes in BDNF levels are negatively correlated with the changes in TNF-α levels (r = -0.37, P = 0.03) but not with the changes in CRP and IL-6 levels. Our findings provide suggestive evidence that omega-3 fatty acids have beneficial effects on cognitive function in patients with MetS, which is paralleled by enhanced BDNF levels.

Mitochondrial Dysfunction in Schizophrenia

Schizophrenia (SCZ) is a severe neurodevelopmental disorder affecting 1% of populations worldwide with a grave disability and socioeconomic burden. Current antipsychotic medications are effective treatments for positive symptoms, but poorly address negative symptoms and cognitive symptoms, warranting the development of better treatment options. Further understanding of SCZ pathogenesis is critical in these endeavors. Accumulating evidence has pointed to the role of mitochondria and metabolic dysregulation in SCZ pathogenesis. This review critically summarizes recent studies associating a compromised mitochondrial function with people with SCZ, including postmortem studies, imaging studies, genetic studies, and induced pluripotent stem cell studies. This review also discusses animal models with mitochondrial dysfunction resulting in SCZ-relevant neurobehavioral abnormalities, as well as restoration of mitochondrial function as potential therapeutic targets. Further understanding of mitochondrial dysfunction in SCZ may open the door to develop novel therapeutic strategies that can address the symptoms that cannot be adequately addressed by current antipsychotics alone.

Dysregulation of amino acids and lipids metabolism in schizophrenia with violence

BACKGROUND

Many studies have related biochemical characteristics to violence and have reported schizophrenia could elevated the risk of violent behaviour. However, the metabolic characteristics of schizophrenia patients with violence (V.SC) are unclear.

METHODS

To explore the metabolic characteristics of schizophrenia with violence and to identify potential biomarkers, untargeted metabolomics was performed by using gas chromatography time-of-flight mass spectrometry to analyse the plasma metabolites of fifty-three V.SC and twenty-four schizophrenia patients without violence (NV.SC). Multivariate and univariate analyses were performed to identify differential metabolites and biomarkers. Violence was assessed by the MacArthur Violence Assessment Study method. Psychiatric symptoms were assessed by the Positive and Negative Syndrome Scale.

RESULTS

Multivariate analysis was unable to distinguish V.SC from NV.SC. Glycerolipid metabolism and phenylalanine, tyrosine and tryptophan biosynthesis were the differential metabolic pathways between V.SC and NV.SC. We confirmed ten metabolites and five metabolites as metabolic biomarkers of V.SC by random forest and support vector machine analysis, respectively. The biomarker panel, including the ratio of L-asparagine to L-aspartic acid, vanillylmandelic acid and glutaric acid, yielded an area under the receiver operating characteristic curve of 0.808.

CONCLUSIONS

This study gives a holistic view of the metabolic phenotype of schizophrenia with violence which is characterized by the dysregulation of lipids and amino acids. These results might provide information for the aetiological understanding and management of violence in schizophrenia; however, this is a preliminary metabolomics study about schizophrenia with violence, which needs to be repeated in future studies.

Volumetric Abnormalities in Violent Schizophrenia Patients on the General Psychiatric Ward

BACKGROUND

In recent years, neuroimaging has been used increasingly to explore the biological underpinnings of violence carried out by schizophrenia patients (SPs). Studies have focused mostly on patients with a history of carrying out severe physical assaults, or comorbid with substance abuse/personality disorder (SA/PD). As a result, participants were unrepresentative and the interpretation of brain-structure changes was confusing. Here, we concentrated on SPs on a general psychiatric ward with a history of relatively lower violence, and individuals comorbid with SA or PD were excluded. We expected to identify the characteristics of brain morphometry in this population, and to explore whether the morphometric changes were universal.

METHODS

Forty-eight violent schizophrenia patients (VSPs), twenty-seven non-VSPs (nVSPs) and 28 nonviolent healthy controls (HCs) were investigated. Voxel-based morphometry was used to evaluate the gray matter volume (GMV) of all study participants. Whole-brain analyses were used to reveal group effects and differences between any two groups. Correlation analyses were undertaken between significant brain regions and behavioral measurements in the VSP group.

RESULTS

Patients showed a significantly smaller GMV in widespread frontal, temporal, and limbic regions compared with HCs. No region was found in which the two patient groups had significantly larger volumes compared with that in HCs. A significant decrease in the GMV of the right fusiform gyrus was found in the VSP group compared with that in the nVSP group (p = 0.004), where the GMV of this region had a negative correlation with the Physical Aggression [subscale of the Modified Overt Aggression Scale (MOAS)] or Hostility score. The VSP group showed a trend of GMV decrease in the left middle temporal cortex compared with that in the nVSP group (p = 0.077). Negative correlation was also found between the GMV of left inferior temporal gyrus/left Superior frontal gyrus, medial and the Hostility score.

CONCLUSIONS

Our results provide initial evidence demonstrating the generalizability of GMV abnormalities in SPs engaged in varying levels of violence, even when SA or PD have not been implicated. GMV reduction was correlated with only the Physical Aggression subscale score of the MOAS, suggesting that this change in brain morphology may be dependent upon different types of violent actions.

Polyunsaturated Fatty Acids: What is Their Role in Treatment of Psychiatric Disorders?

In the central nervous system omega-3 fatty acids modulate cell signaling and affect dopaminergic and serotonergic pathways. On this basis, a new application for omega-3 fatty acids has been proposed, concerning the treatment of several psychiatric disorders. The present article is an update of a previous systematic review and is aimed to provide a complete report of data published in the period between 1980 and 2019 on efficacy and tolerability of omega-3 fatty acids in psychiatric disorders. In July 2019, an electronic search on PUBMED, Medline and PsychINFO of all RCTs, systematic reviews and meta-analyses on omega-3 fatty acids and psychiatric disorders without any filter or MESH restriction was performed. After eligibility processes, the final number of records included in this review was 126. One hundred and two of these studies were RCTs, while 24 were reviews and meta-analyses. The role of omega-3 fatty acids was studied in schizophrenia, major depression, bipolar disorder, anxiety disorders, obsessive-compulsive disorder, post-traumatic stress disorder, attention deficit hyperactivity disorder (ADHD), autism spectrum disorders, eating disorders, substance use disorder and borderline personality disorder. The main evidence of the efficacy of omega-3 fatty acids has been obtained in treating depressive symptoms in patients with major depression and, to a lesser degree, bipolar depression. Some efficacy was also found in early phases of schizophrenia in addition to antipsychotic treatment, but not in the chronic phases of psychosis. Small beneficial effects of omega-3 fatty acids were observed in ADHD and positive results were reported in a few trials on core symptoms of borderline personality disorder. For other psychiatric disorders results are inconsistent.

Nutrient and genetic biomarkers of nutraceutical treatment response in mood and psychotic disorders: a systematic review

Objective: Nutrient and genetic biomarkers in nutraceutical trials may allow for the personalisation of nutraceutical treatment and assist in predicting treatment response. We aimed to synthesise the findings of trials which have included these biomarkers to determine which may be most useful for predicting nutraceutical response in mood and psychotic disorders.Methods: A systematic review was conducted assessing available literature concerning nutraceutical clinical trials in mood and psychotic disorders (major depression, bipolar disorder, schizophrenia) with baseline and endpoint blood nutrient markers or genetic data available.Results: We identified 35 eligible studies (total n = 3836 participants) examining baseline and endpoint nutrient biomarkers and/or genetic polymorphisms. The key result, as reported in 10 out of 11 omega-3 studies, was a strong association between polyunsaturated fatty acid concentrations (mostly EPA and DHA) and psychiatric outcomes, although the exact nature of the association varied between studies and diagnoses. There was no consistent evidence for levels of other nutrients (including Vitamin D, SAM/SAH ratios, carnitine, folate and vitamin B12) relating to treatment response. The evidence for associations between one-carbon cycle genotypes (e.g. MTHFR C677 T, MTR and FOLH1) and treatment response was also inconsistent.Discussion: The available data tentatively supports omega-3 indices as biomarkers of response to omega-3 treatments in mood disorders. Further research with larger samples examining combinations of polymorphisms is required to determine if any genetic factors influence nutraceutical response in mood and psychotic disorders.

Adjunctive use of anti-inflammatory drugs for schizophrenia: A meta-analytic investigation of randomized controlled trials

OBJECTIVE

Recent evidence suggests that adjuvant anti-inflammatory agents could improve the symptoms of patients with schizophrenia. However, the effects of the adjuvant anti-inflammatory agents on cognitive function, general functioning and side effects have not yet been systematically investigated. The present meta-analysis aimed to explore the effects of anti-inflammatory agents in patients with schizophrenia comprehensively.

METHOD

We performed a literature search in online databases, including PubMed, EMBASE and the Cochrane Database of Systematic Reviews. Randomized, placebo-controlled double-blind studies that investigated clinical outcomes including psychopathology, neurocognition, general functioning and extrapyramidal side effects were included. The examined anti-inflammatory agents included aspirin, celecoxib, omega-3 fatty acids, estrogen, selective estrogen receptor modulator, pregnenolone, N-acetylcysteine, minocycline, davunetide and erythropoietin.

RESULTS

Sixty-two double-blind randomized clinical trials studying 2914 patients with schizophrenia met the inclusion criteria for quantitative analysis. Significant overall effects were found for anti-inflammatory agents for reducing total, positive and negative symptom scores in the Positive and Negative Syndrome Scale. Cognitive improvements were significant with minocycline and pregnenolone augmentation therapy. General functioning was significantly enhanced by overall anti-inflammatory agents. There were no significant differences in side effects compared with placebo. Baseline total Positive and Negative Syndrome Scale score and illness duration were identified as moderating factors in the effects of anti-inflammatory augmentation on psychiatric symptom improvements.

CONCLUSION

The comparative evaluation of efficacy and safety supported the use of anti-inflammatory adjuvant therapy over the use of antipsychotics alone. However, future studies could focus on patients with homogeneous clinical profile to figure out more detailed effects of anti-inflammatory therapy.

Autoimmune phenotypes in schizophrenia reveal novel treatment targets

Typical and atypical antipsychotics are the first-line treatments for schizophrenia, but these classes of drugs are not universally effective, and they can have serious side effects that impact compliance. Antipsychotic drugs generally target the dopamine pathways with some variation. As research of schizophrenia pathophysiology has shifted away from a strictly dopamine-centric focus, the development of new pharmacotherapies has waned. A field of inquiry with centuries-old roots is gaining traction in psychiatric research circles and may represent a new frontier for drug discovery in schizophrenia. At the forefront of this investigative effort is the immune system and its many components, pathways and phenotypes, which are now known to actively engage the brain. Studies in schizophrenia reveal an intricate association of environmentally-driven immune activation in concert with a disrupted genetic template. A consistent conduit through this gene-environmental milieu is the gut-brain axis, which when dysregulated can generate pathological autoimmunity. In this review, we present epidemiological and biochemical evidence in support of an autoimmune component in schizophrenia and depict gut processes and a dysbiotic microbiome as a source and perpetuator of autoimmune dysfunction in the brain. Within this framework, we review the role of infectious agents, inflammation, gut dysbioses and autoantibody propagation on CNS pathologies such as neurotransmitter receptor hypofunction and complement pathway-mediated synaptic pruning. We then review the new pharmacotherapeutic horizon and novel agents directed to impact these pathological conditions. At the core of this discourse is the understanding that schizophrenia is etiologically and pathophysiologically heterogeneous and thus its treatment requires individualized attention with disease state variants diagnosed with objective biomarkers.