Homocysteine-reducing strategies improve symptoms in chronic schizophrenic patients with hyperhomocysteinemia

Nutraceuticals and phytoceuticals in the treatment of schizophrenia: a systematic review and network meta-analysis "Nutra NMA SCZ"

Sub-optimal response in schizophrenia is frequent, warranting augmentation strategies over treatment-as-usual (TAU). We assessed nutraceuticals/phytoceutical augmentation strategies via network meta-analysis. Randomized controlled trials in schizophrenia/schizoaffective disorder were identified via the following databases: PubMed, MEDLINE, EMBASE, Scopus, PsycINFO, CENTRAL, and ClinicalTrials.gov. Change (Standardized Mean Difference = SMD) in total symptomatology and acceptability (Risk Ratio = RR) were co-primary outcomes. Secondary outcomes were positive, negative, cognitive, and depressive symptom changes, general psychopathology, tolerability, and response rates. We conducted subset analyses by disease phase and sensitivity analyses by risk of bias and assessed global/local inconsistency, publication bias, risk of bias, and confidence in the evidence. The systematic review included 49 records documenting 50 studies (n = 2384) documenting 22 interventions. Citicoline (SMD =-1.05,95%CI = -1.85; -0.24), L-lysine (SMD = -1.04,95%CI = -1.84; -0.25), N-acetylcysteine (SMD = -0.87, 95%CI = -1.27; -0.47) and sarcosine (SMD = -0.5,95%CI = -0.87-0.13) outperformed placebo for total symptomatology. High heterogeneity (tau2 = 0.10, I2 = 55.9%) and global inconsistency (Q = 40.79, df = 18, p = 0.002) emerged without publication bias (Egger's test, p = 0.42). Sarcosine improved negative symptoms (SMD = -0.65, 95%CI = -1.10; -0.19). N-acetylcysteine improved negative symptoms (SMD = -0.90, 95%CI = -1.42; -0.39)/general psychopathology (SMD = -0.76, 95%CI = -1.39; -0.13). No compound improved total symptomatology within acute phase studies (k = 7, n = 422). Sarcosine (SMD = -1.26,95%CI = -1.91; -0.60), citicoline (SMD = -1.05,95%CI = -1.65;-0.44), and N-acetylcysteine (SMD = -0.55,95%CI = -0.92,-0.19) outperformed placebo augmentation in clinically stable participants. Sensitivity analyses removing high-risk-of-bias studies confirmed overall findings in all phases and clinically stable samples. In contrast, the acute phase analysis restricted to low risk-of-bias studies showed a superior effect vs. placebo for N-acetylcysteine (SMD = -1.10, 95%CI = -1.75,-0.45), L-lysine (SMD = -1.05,95%CI = -1.55, -0.19), omega-3 fatty acids (SMD = -0.83,95%CI = -1.31, -0.34) and withania somnifera (SMD = -0.71,95%CI = -1.21,-0.22). Citicoline (SMD = -1.05,95%CI = -1.86,-0.23), L-lysine (SMD = -1.04,95%CI = -1.84,-0.24), N-acetylcysteine (SMD = -0.89,95%CI = -1.35,-0.43) and sarcosine (SMD = -0.61,95%CI = -1.02,-0.21) outperformed placebo augmentation of TAU ("any phase"). Drop-out due to any cause or adverse events did not differ between nutraceutical/phytoceutical vs. placebo+TAU. Sarcosine, citicoline, and N-acetylcysteine are promising augmentation interventions in stable patients with schizophrenia, yet the quality of evidence is low to very low. Further high-quality trials in acute phases/specific outcomes/difficult-to-treat schizophrenia are warranted.

Folate and vitamin B12 supplementation in patients with schizophrenia and low serum folate level: A 24-week randomized, double-blind, placebo-controlled study

PURPOSE

We aimed to evaluate the effects of folate and vitamin B12 on psychopathology in patients with schizophrenia and low serum folate levels.

METHODS

Fifty-five schizophrenia patients with serum folate levels lower than 6 mg/L were randomized in a 2:1 ratio to supplementation with 5 mg of folate and 500 μg of vitamin B12 per day (the folate group, n = 36) or placebo (the placebo group, n = 19) for 24 weeks. We evaluated patients' symptomatology with the Positive and Negative Symptom Scale (PANSS) and cognitive functions with Cogstate.

RESULTS

During the 24-week intervention, serum folate and vitamin B12 levels significantly increased, and homocysteine level significantly decreased in the folate group, but these markers did not significantly change in the placebo group. There were no significant changes in scores of total and each subscale of PANSS, and Cogstate between the folate and placebo groups. A subgroup analysis within the folate groups revealed no significant differences in the changes of psychotic symptoms severity or cognitive functions among patients with different degrees of folate level increments.

CONCLUSION

Our finding suggested that the extent of increased folate levels did not exert a notable impact on the changes of psychotic symptoms severity or cognitive function in our patients. It may also due to the relatively stable condition in our recruited patients, so supplementation of folate cannot show its effectiveness. Whether folate can improve psychopathology in moderate to severe patients with schizophrenia should be evaluated with a larger sample size in the future.

Vitamin B12 Supplementation in Psychiatric Practice

PURPOSE OF REVIEW

Vitamin B12 (B12, cobalamin) deficiency has been associated with neuropsychiatric symptoms, suggesting a role for B12 supplementation both as a treatment for psychiatric symptoms due to B12 deficiency and as an augmentation strategy for pharmacological treatments of psychiatric disorders. This critical review discusses the major causes of B12 deficiency, the range of psychiatric and non-psychiatric manifestations of B12 deficiency, the indications for testing B12 levels, and the evidence for B12 supplementation for major psychiatric disorders.

RECENT FINDINGS

We find that high-quality evidence shows no benefit to routine B12 supplementation for mild depressive symptoms or to prevent depression. There is very limited evidence on the role of B12 supplementation to augment antidepressants. No high-quality evidence to date suggests a role for routine B12 supplementation in any other major psychiatric disorder. No formal guidelines indicate when clinicians should test B12 levels for common psychiatric symptoms, in the absence of major risk factors for deficiency or cardinal symptoms of deficiency. No robust evidence currently supports routine B12 supplementation for major psychiatric disorders. However, psychiatrists should be aware of the important risk factors for B12 deficiency and should be able to identify symptoms of B12 deficiency, which requires prompt testing, medical workup, and treatment. Testing for B12 deficiency should be considered for atypical or severe psychiatric presentations.

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.

Epigenetics, Nutrition, and the Brain: Improving Mental Health through Diet

The relationship between nutrition and brain health is intricate. Studies suggest that nutrients during early life impact not only human physiology but also mental health. Although the exact molecular mechanisms that depict this relationship remain unclear, there are indications that environmental factors such as eating, lifestyle habits, stress, and physical activity, influence our genes and modulate their function by epigenetic mechanisms to shape mental health outcomes. Epigenetic mechanisms act as crucial link between genes and environmental influences, proving that non-genetic factors could have enduring effects on the epigenome and influence health trajectories. We review studies that demonstrated an epigenetic mechanism of action of nutrition on mental health, focusing on the role of specific micronutrients during critical stages of brain development. The methyl-donor micronutrients of the one-carbon metabolism, such as choline, betaine, methionine, folic acid, VitB6 and VitB12 play critical roles in various physiological processes, including DNA and histone methylation. These micronutrients have been shown to alter gene function and susceptibility to diseases including mental health and metabolic disorders. Understanding how micronutrients influence metabolic genes in humans can lead to the implementation of early nutritional interventions to reduce the risk of developing metabolic and mental health disorders later in life.

Nutraceuticals and phytoceuticals in the treatment of schizophrenia: a systematic review and network meta-analysis

Background

Sub-optimal response in schizophrenia is frequent, warranting augmentation strategies over treatment-as-usual (TAU).

Methods

We assessed nutraceuticals/phytoceutical augmentation strategies via network meta-analysis. Randomized controlled trials in schizophrenia/schizoaffective disorder were identified via the following databases: PubMed, MEDLINE, EMBASE, Scopus, PsycINFO, CENTRAL, and ClinicalTrials.gov. Change (Standardized Mean Difference=SMD) in total symptomatology and acceptability (Risk Ratio=RR) were co-primary outcomes. Secondary outcomes were positive, negative, cognitive, and depressive symptom changes, general psychopathology, tolerability, and response rates. We conducted subset analyses by disease phase and sensitivity analyses by risk of bias and assessed global/local inconsistency, publication bias, risk of bias, and confidence in the evidence.

Results

The systematic review included 49 records documenting 50 studies (n=2,384) documenting 22 interventions. Citicoline (SMD=-1.05,95%CI=-1.85; -.24), L-lysine (SMD=-1.04,95%CI=-1.84;-.25), N-acetylcysteine (SMD=-.87,95%CI=-1.27;-.47) and sarcosine (SMD=-.5,95%CI=-.87-.13) outperformed placebo for total symptomatology. High heterogeneity (tau2=.10, I2=55.9%) and global inconsistency (Q=40.79, df=18, p=.002) emerged without publication bias (Egger's test, p=.42). Sarcosine improved negative symptoms (SMD=-.65, 95%CI=-1.10; -.19). N-acetylcysteine improved negative symptoms (SMD=-.90, 95%CI=-1.42; -.39)/general psychopathology (SMD=-.76, 95%CI=-1.39; -.13). No compound improved total symptomatology within acute phase studies (k=7, n=422). Sarcosine (SMD=-1.26,95%CI=-1.91; -.60), citicoline (SMD=-1.05,95%CI=-1.65;-.44), and N-acetylcysteine (SMD=-.55,95%CI=-.92,-.19) outperformed placebo augmentation in clinically stable participants. Sensitivity analyses removing high-risk-of-bias studies confirmed overall findings in all phases and clinically stable samples. In contrast, the acute phase analysis restricted to low risk-of-bias studies showed a superior effect vs. placebo for N-acetylcysteine (SMD=-1.10,95%CI=-1.75,-.45), L-lysine (SMD=-1.05,95%CI=-1.55,-.19), omega-3 fatty acids (SMD=-.83,95%CI=-1.31,-.34) and withania somnifera (SMD=-.71,95%CI=-1.21,-.22). Citicoline (SMD=-1.05,95%CI=-1.86,-.23), L-lysine (SMD=-1.04,95%CI=-1.84,-.24), N-acetylcysteine (SMD=-.89,95%CI=-1.35,-.43) and sarcosine (SMD=-.61,95%CI=-1.02,-.21) outperformed placebo augmentation of TAU ("any phase"). Drop-out due to any cause or adverse events did not differ between nutraceutical/phytoceutical vs. placebo+TAU.

Conclusions

Sarcosine, citicoline, and N-acetylcysteine are promising augmentation interventions in stable patients with schizophrenia, yet the quality of evidence is low to very low. Further high-quality trials in acute phases/specific outcomes/difficult-to-treat schizophrenia are warranted.

Complementary/Integrative Medicine Treatment and Prevention of Youth Psychosis

The rationale for CIM treatments in youth psychoses is to optimize treatment by targeting symptoms not resolved by antipsychotics, such as negative symptoms (major drivers of disability). Adjunctive omega-3 fatty acids (ω-3 FA) or N-acetyl cystine (NAC usage for > 24-week) can potentially reduce negative symptoms and improve function. ω-3 FA or exercise may prevent progression to psychosis in youth (in prodromal stage). Weekly 90-minute moderate to vigorous physical activity or aerobic exercise can reduce positive and negative symptoms. Awaiting better research, CIM agents are also recommended because they are devoid of any serious side-effects.

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.

The Effects of Plasma Homocysteine Level on the Risk of Three Major Psychiatric Disorders: A Mendelian Randomization Study

BACKGROUND

Higher homocysteine (Hcy) level has been suggested to be associated with major psychiatric disorders (MPDs), such as schizophrenia (SCZ), bipolar disorder (BD), and major depressive disorder (MDD). We investigated the causal relationships between plasma Hcy level and MPDs risks using the Mendelian randomization (MR) method.

METHODS

We selected 18 loci associated with plasma Hcy level from a large-scale genome-wide association study (GWAS) as genetic instruments. Genetic associations with SCZ, MDD, BD and BD subtypes (BD-I and BD-II) were extracted from several GWAS datasets from the Psychiatric Genomics Consortium. We used the Generalized Summary-data-based Mendelian Randomization (GSMR) method to estimate the associations of genetically predicted plasma Hcy levels with MPDs risks. We also performed inverse variance-weighted (IVW) analysis to verify the GSMR results and used MR-Egger regression and leave-one-out analysis to test the assumptions for a valid MR analysis.

RESULTS

Genetically predicted plasma Hcy levels were associated with risks of SCZ (odds ratio [OR] = 1.12, P _GSMR = 1.73 × 10^-3) and BD-I (OR = 1.14, P _IVW = 5.23 × 10^-3) after Bonferroni correction. These associations were statistically significant when using IVW analysis (SCZ: OR = 1.11, P _IVW = 2.74 × 10^-3; BD-I: OR = 1.13, P _IVW = 9.44 × 10^-3). Furthermore, no significant horizontal pleiotropy was found by sensitivity analysis, and leave-one-out analyses showed no specific SNP affected the overall estimate. However, genetically determined plasma Hcy levels were not causally associated with MDD, BD, or BD-II risks.

CONCLUSION

Our results suggest that elevated plasma Hcy levels may increase the risk of SCZ or BD-I. Further randomized clinical trials are warranted to validate the MR findings in our study.

Fingertip advanced glycation end products and psychotic symptoms among adolescents

Case control studies have suggested that advanced glycation end products play a key role in the pathophysiology of chronic schizophrenia. However, the longitudinal association between advanced glycation end products and psychotic symptoms among drug-naïve adolescents remains unclear. This study examined whether advanced glycation end products could predict the trajectory of psychotic symptoms in drug-naive adolescents using data from prospective population-based biomarker subsample study of the Tokyo Teen Cohort. A total of 277 community-dwelling adolescents aged 13 years without antipsychotic medication were analyzed. Fingertip advanced glycation end products were measured in adolescents using noninvasive technology that can be used quickly. The trajectory of psychotic symptoms in a 12-month follow-up was assessed by experienced psychiatrists using a semi-structured interview. Of the 277 participants, 13 (4.7%) experienced persistent psychotic symptoms (psychotic symptoms at baseline and follow-up), 65 (23.5%) experienced transient psychotic symptoms (psychotic symptoms at baseline or follow-up), and 199 (71.8%) did not have psychotic symptoms. Multinomial logistic regression analysis adjusted for age and sex revealed that baseline fingertip advanced glycation end products might predict the risk of persistent psychotic symptoms (odds ratio = 1.68; 95% confidence interval, 1.05-2.69; P = 0.03). Altogether, fingertip advanced glycation end products potentially predicted the trajectory of psychotic symptoms among drug-naive adolescents, which indicated its involvement in the pathophysiology of early psychosis. Further studies are required to identify strategies to reduce adolescent advanced glycation end products, which may contribute to preventing the onset of psychosis.

Towards Tailored Gut Microbiome-Based and Dietary Interventions for Promoting the Development and Maintenance of a Healthy Brain

Mental health is determined by a complex interplay between the Neurological Exposome and the Human Genome. Multiple genetic and non-genetic (exposome) factors interact early in life, modulating the risk of developing the most common complex neurodevelopmental disorders (NDDs), with potential long-term consequences on health. To date, the understating of the precise etiology underpinning these neurological alterations, and their clinical management pose a challenge. The crucial role played by diet and gut microbiota in brain development and functioning would indicate that modulating the gut-brain axis may help protect against the onset and progression of mental-health disorders. Some nutritional deficiencies and gut microbiota alterations have been linked to NDDs, suggesting their potential pathogenic implications. In addition, certain dietary interventions have emerged as promising alternatives or adjuvant strategies for improving the management of particular NDDs, at least in particular subsets of subjects. The gut microbiota can be a key to mediating the effects of other exposome factors such as diet on mental health, and ongoing research in Psychiatry and Neuropediatrics is developing Precision Nutrition Models to classify subjects according to a diet response prediction based on specific individual features, including microbiome signatures. Here, we review current scientific evidence for the impact of early life environmental factors, including diet, on gut microbiota and neuro-development, emphasizing the potential long-term consequences on health; and also summarize the state of the art regarding the mechanisms underlying diet and gut microbiota influence on the brain-gut axis. Furthermore, we describe the evidence supporting the key role played by gut microbiota, diet and nutrition in neurodevelopment, as well as the effectiveness of certain dietary and microbiome-based interventions aimed at preventing or treating NDDs. Finally, we emphasize the need for further research to gain greater insight into the complex interplay between diet, gut microbiome and brain development. Such knowledge would help towards achieving tailored integrative treatments, including personalized nutrition.

Prevalence and clinical demography of hyperhomocysteinemia in Han Chinese patients with schizophrenia

Previous studies have shown that high homocysteine worsens the occurrence, symptoms, and prognosis of patients with schizophrenia. The purpose of this study was to evaluate the prevalence, clinical correlation, and demographic characteristics of hyperhomocysteinemia in Han Chinese schizophrenia patients. In this study, we enrolled 330 schizophrenia patients and 190 healthy controls. Positive and Negative Syndrome Scale (PANSS) was used to evaluate the psychiatric symptoms of patients with schizophrenia. The plasma homocysteine level was measured by the enzyme cycle method and the concentration of homocysteine > 15 μmol/L was defined as hyperhomocysteinemia. The prevalence of hyperhomocysteinemia in Han Chinese schizophrenia patients and healthy controls was 55.05% and 26.98%, respectively. Schizophrenia patients with hyperhomocysteinemia had more male proportion, older age, higher smoking rate, lower HDL level, higher PANSS total score, and higher negative factor than those patients without hyperhomocysteinemia. Binary logical regression result showed that gender and age were the independent risk factors of hyperhomocysteinemia. Han Chinese patients with schizophrenia had high prevalence hyperhomocysteinemia than healthy controls, and elderly male patients have a higher risk of hyperhomocysteinemia. This study was registered in the China Clinical Trial Registration Center (chiCTR 1800017044).

[The effect of various forms of folates on cognitive functions in patients with chronic schizophrenia]

OBJECTIVE

To assess the dynamics of cognitive functions in patients with schizophrenia during intake of various forms of folate as an add-on to antipsychotic therapy.

MATERIAL AND METHODS

Using a battery of cognitive tests, the authors evaluated the dynamics of cognitive functions in 3 groups of patients with schizophrenia who received folic acid (n=25), metafolin (n=25) during 4 weeks and in the control group (n=25). Genetic variants of the polymorphism of the folate metabolism enzyme methylenetetrahydrofolate reductase (MTHFR) 677C>T were determined using real-time PCR. Only the carriers of the minor T allele were included in the study.

RESULTS AND CONCLUSION

The improvement of certain cognitive functions was noted after folate administration, it was more pronounced and statistically significant in the metapholin group. The results hold promises for further studies of prolonged use of folate in prophylactic doses for schizophrenia.

Homocysteine level, body mass index and clinical correlates in Chinese Han patients with schizophrenia

Obesity is common comorbidity in patients with schizophrenia. Previous studies have reported that homocysteine (Hcy) is increased in schizophrenia. However, no study has reported the association between BMI and Hcy levels in schizophrenia. This cross-sectional naturalistic study aimed to evaluate the relationship between BMI, Hcy and clinical symptoms in Chinese Han patients with chronic schizophrenia. Clinical and anthropometric data as well as plasma Hcy level and glycolipid parameters were collected. Psychopathology was measured with the Positive and Negative Syndrome Scale (PANSS). Our results showed that compared with the low BMI group, the high BMI group had a higher PANSS general psychopathology subscore, higher levels of blood glucose, total cholesterol and high-density lipoprotein (HDL) cholesterol (all p < 0.05). Hcy levels were negatively associated with BMI in patients (p < 0.001). Hcy level, the PANSS general psychopathology subscale, total cholesterol and education (all p < 0.05) were the influencing factors of high BMI. Our study suggest that Hcy level may be associated with BMI in patients with schizophrenia. Moreover, patients with high BMI show more severe clinical symptoms and higher glucose and lipid levels.

Efficient Prediction of Vitamin B Deficiencies via Machine-Learning Using Routine Blood Test Results in Patients With Intense Psychiatric Episode

BACKGROUND

Vitamin B deficiency is common worldwide and may lead to psychiatric symptoms; however, vitamin B deficiency epidemiology in patients with intense psychiatric episode has rarely been examined. Moreover, vitamin deficiency testing is costly and time-consuming, which has hampered effectively ruling out vitamin deficiency-induced intense psychiatric symptoms. In this study, we aimed to clarify the epidemiology of these deficiencies and efficiently predict them using machine-learning models from patient characteristics and routine blood test results that can be obtained within one hour.

METHODS

We reviewed 497 consecutive patients, who are deemed to be at imminent risk of seriously harming themselves or others, over a period of 2 years in a single psychiatric tertiary-care center. Machine-learning models (k-nearest neighbors, logistic regression, support vector machine, and random forest) were trained to predict each deficiency from age, sex, and 29 routine blood test results gathered in the period from September 2015 to December 2016. The models were validated using a dataset collected from January 2017 through August 2017.

RESULTS

We found that 112 (22.5%), 80 (16.1%), and 72 (14.5%) patients had vitamin B1, vitamin B12, and folate (vitamin B9) deficiency, respectively. Further, the machine-learning models were well generalized to predict deficiency in the future unseen data, especially using random forest; areas under the receiver operating characteristic curves for the validation dataset (i.e., the dataset not used for training the models) were 0.716, 0.599, and 0.796, respectively. The Gini importance of these vitamins provided further evidence of a relationship between these vitamins and the complete blood count, while also indicating a hitherto rarely considered, potential association between these vitamins and alkaline phosphatase (ALP) or thyroid stimulating hormone (TSH).

DISCUSSION

This study demonstrates that machine-learning can efficiently predict some vitamin deficiencies in patients with active psychiatric symptoms, based on the largest cohort to date with intense psychiatric episode. The prediction method may expedite risk stratification and clinical decision-making regarding whether replacement therapy should be prescribed. Further research includes validating its external generalizability in other clinical situations and clarify whether interventions based on this method could improve patient care and cost-effectiveness.

Comparison of serum levels of asymmetric dimethylarginine between patients who take two types of atypical anti psychotics

Background: Schizophrenia is associated with increased cardiovascular morbidity. Asymmetric dimethylarginine (ADMA) has been suggested as a cardiovascular biomarker. Treatment with atypical antipsychotics can increase some traditional risk factors of coronary artery disease. In addition to traditional risk factors, this study is carried out as a comparison of serum levels of ADMA and non-traditional factors among patients who take two types of atypical antipsychotics. Methods: In this clinical study, 57 schizophrenic patients with multiple episodes and 20 healthy voluntaries that fulfilled inclusion and exclusion criteria were entered into the study. The patients were divided into 3 groups (18 patients received risperidone alone, 20 patients received clozapine alone and 19 patients did not receive any drug). Plasma concentrations of ADMA, high-sensitivity Creactive protein (hs-CRP) and homocysteine were measured through enzyme-linked immunosorbent assay (ELISA), and traditional risk factors of metabolic syndrome were measured. Results: Mean age of participants was 46.08±12.54 years. Moreover, the traditional (High-density lipoprotein (HDL), total cholesterol, waistline, and Body Mass Index (BMI)) and non-traditional factors (Homocysteine, hs-CRP) and ADMA were higher in patients with schizophrenia compared to healthy group (p≤ 0.05). Also, in the clozapine group, all mentioned non-traditional factors and ADMA were significantly higher than other groups (p≤ 0.05). Conclusion: In the clozapine group, levels of non-traditional factors and ADMA were significantly higher which indicates these patients are at risk of cardiovascular disease.

Folic Acid and Vitamin B12 Supplementation on Male Patients with Schizophrenia Predominant Negative Symptoms

Background:

Schizophrenia is a chronic mental disorder that affects approximately 1% of the world’s population. Particularly, negative symptoms are frequently resistant and are the main contributors to the disability on schizophrenia patients. Folic acid and vitamin B12 supplementation is the safe and affordable approach, which can significantly improve the outcome on the patients with residual symptoms.

Objectives:

We aimed to understand the difference of negative subscale of Positive and Negative Syndrome Scale (PANSS) Score on patients with schizophrenia who receive risperidone with the addition folic acid and Vitamin B12 and patients who receive only risperidone after 6 weeks.

Methods:

This study is a quasi experimental pre-test and post-test designs that are divided into two groups, they are group receiving risperidone with the addition of folic acid and vitamin B12 and the group receiving only risperidone. Diagnosis of schizophrenia according to the International Classification of Diseases (ICD-10) criteria and negative symptoms assessed by using negative subscale of PANSS Scores are observed. Statistical analysis is conducted using Statistical Package for the Social Sciences (SPSS) software.

Results:

There was a significant difference in the mean score of negative-scale PANSS scores at the end of week 6 between the group receiving folic acid and vitamin B12 supplementation and the group receiving only risperidone with p = 0.002; p <0.05.

Conclusion:

Folic acid and vitamin B12 Supplementation provide benefits to patients schizophrenia.

Evaluation of hyperhomocysteinemia prevalence and its influence on the selected cognitive functions in patients with schizophrenia

There is evidence that hyperhomocysteinemia may be associated with the development of schizophrenia and cognitive impairment. Therefore, the aim of this study was to analyze the relationship between cognitive functions and normal homocysteine concentrations vs. hyperhomocysteinemia in schizophrenia patients before and after supplementation with vitamins B6, B12 and folate. An 8-week prospective, non-randomized study enrolled 122 adult patients with schizophrenia (67F/55M, mean age 43.54 ± 11.94 years). Homocysteine concentrations were measured in all individuals and afterwards hyperhomocysteinemia patients (n = 42) were divided into two subgroups: treated with oral vitamins supplementation (B6 - 25 mg/d, B12 - 20 μg/d, folate - 2,5 mg/d) (n = 22) and without supplementation (n = 20). The assessment of schizophrenia symptoms severity in study group was performed using the Positive and Negative Syndrome Scale (PANSS). Cognitive functions were evaluated using the Stroop test and the Trail Making Test (TMT). We observed a higher prevalence of hyperhomocysteinemia in schizophrenia patients (34.4%) in comparison to the general population. Individuals with schizophrenia and coexisting hyperhomocysteinemia had worse performance on the Stroop and the TMT tests as well as higher PANSS scores. In these patients, supplementation with vitamins effectively decreased the homocysteine concentrations to the normal values, however there was no statistically significant improvement in the PANSS and cognitive test scores, except a significant decrease in the number of the Stroop test errors. We conclude that significant results obtained in this study show that there is a relationship between homocysteine blood concentration and schizophrenia severity. Moreover, homocysteine concentration lowering might be beneficial in schizophrenia patients with hyperhomocysteinemia in terms of cognitive functions improvement.

Antiepileptic drug-induced psychosis associated with MTHFR C677T: a case report

Background

Various antiepileptic drugs can potentially cause psychiatric side effects in patients with epilepsy, but the precise mechanism of these actions remains unknown. In recent years, the common polymorphism C677T in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene has attracted attention for its role in the onset of psychiatric diseases. MTHFR and several vitamins (as cofactors) are crucial for remethylation of homocysteine via folate and homocysteine metabolism. We report a case of a Japanese patient who presented with reversible schizophrenia-like symptoms during antiepileptic drug therapy.

Case presentation

Our patient had frontal lobe epilepsy and had been treated with several antiepileptic drugs since the age of 13 years. He developed auditory hallucinations and multiple personalities at 17 years of age, several months after the initiation of phenytoin and phenobarbital, despite these antiepileptic drugs being used within the therapeutic ranges. Genetic analysis revealed that he was homozygous for the C677T polymorphism of MTHFR. Hyperhomocysteinemia, hypomethionemia, and multiple vitamin deficiencies, including folate, riboflavin, and pyridoxal, were identified at the age of 23 years. Vitamin supplementation and alteration of the antiepileptic drugs improved his psychotic symptoms. Multiple vitamin deficiencies with homozygous MTHFR C677T should be considered in patients presenting with schizophrenia-like symptoms during antiepileptic drug therapy.

Conclusions

To the best of our knowledge, this is the first report of antiepileptic drug-induced psychosis associated with homozygous C677T and multiple vitamin deficiencies. Our findings will contribute to the elucidation of the pathogenesis of the psychiatric side effects of antiepileptic drugs and lead to improved medical management for patients with epilepsy.

The Vitamins in Psychosis Study: A Randomized, Double-Blind, Placebo-Controlled Trial of the Effects of Vitamins B12, B6, and Folic Acid on Symptoms and Neurocognition in First-Episode Psychosis

BACKGROUND

Elevated homocysteine is observed in schizophrenia and associated with illness severity. The aim of this study was to determine whether vitamins B₁₂, B₆, and folic acid lower homocysteine and improve symptomatology and neurocognition in first-episode psychosis. Whether baseline homocysteine, genetic variation, sex, and diagnosis interact with B-vitamin treatment on outcomes was also examined.

METHODS

A randomized, double-blind, placebo-controlled trial was used. A total of 120 patients with first-episode psychosis were randomized to an adjunctive B-vitamin supplement (containing folic acid [5 mg], B₁₂ [0.4 mg], and B₆ [50 mg]) or placebo, taken once daily for 12 weeks. Coprimary outcomes were change in total symptomatology (Positive and Negative Syndrome Scale) and composite neurocognition. Secondary outcomes included additional measures of symptoms, neurocognition, functioning, tolerability, and safety.

RESULTS

B-vitamin supplementation reduced homocysteine levels (p = .003, effect size = -0.65). B-vitamin supplementation had no significant effects on Positive and Negative Syndrome Scale total (p = .749) or composite neurocognition (p = .785). There were no significant group differences in secondary symptom domains. A significant group difference in the attention/vigilance domain (p = .024, effect size = 0.49) showed that the B-vitamin group remained stable and the placebo group declined in performance. In addition, 14% of the sample had elevated baseline homocysteine levels, which was associated with greater improvements in one measure of attention/vigilance following B-vitamin supplementation. Being female and having affective psychosis was associated with improved neurocognition in select domains following B-vitamin supplementation. Genetic variation did not influence B-vitamin treatment response.

CONCLUSIONS

While 12-week B-vitamin supplementation might not improve overall psychopathology and global neurocognition, it may have specific neuroprotective properties in attention/vigilance, particularly in patients with elevated homocysteine levels, patients with affective psychosis, and female patients. Results support a personalized medicine approach to vitamin supplementation in first-episode psychosis.

Folic acid/methylfolate for the treatment of psychopathology in schizophrenia: a systematic review and meta-analysis

RATIONALE

This study aims to examine whether folate/folic acid/methylfolate/folinic acid supplemented to antipsychotics (FA + AP) is beneficial in schizophrenia treatment.

OBJECTIVE

We conducted a comprehensive systematic review and meta-analysis of double-blind, placebo-controlled, randomized clinical trials (RCTs) of FA + AP for schizophrenia.

METHODS

The primary outcome was an improvement in total symptoms. Other outcomes were psychopathology subscales (positive, negative, general, and depressive symptoms), discontinuation due to all-cause and adverse events, and individual adverse events. The meta-analysis evaluated the effect size based on a random-effects model.

RESULTS

Although we included ten RCTs with 925 patients in total (seven folic acid RCTs (n = 789), two methylfolate RCTs (n = 96), and one folinic acid RCT (n = 40)) in the systematic review, only seven RCTs were included in the meta-analysis. Pooled FA + AP treatments were not superior to placebo + AP in the improvement of total (N = 7, n = 340; standardized mean difference (SMD) = - 0.20, 95% confidence interval (CI) = - 0.41, 0.02, p = 0.08, I² = 0%), positive, general, or depressive symptoms. Pooled FA + AP treatments were more effective than placebo + AP for negative symptoms (N = 5, n = 281; SMD = -0.25, 95% CI = -0.49, -0.01, p = 0.04, I² = 0%). Although pooled FA + AP treatments were associated with a lower incidence of serious adverse events than placebo treatments (N = 4, n = 241; risk ratio = 0.32, 95% CI = 0.12-0.82, p = 0.02, I² = 0%; number needed to harm = not significant), there were no significant differences in other safety outcomes between both treatments.

CONCLUSIONS

Our findings suggest that pooled FA + AP treatment improves negative symptoms in schizophrenia patients. Moreover, this treatment was well tolerated. However, because our results might exhibit a small-study effect, future studies with a larger sample should be conducted to obtain more robust results.

Synaptic Effects of Dopamine Breakdown and Their Relation to Schizophrenia-Linked Working Memory Deficits

Working memory is the ability to hold information "online" over a time delay in order to perform a task. This kind of memory is encoded in the brain by persistent neural activity that outlasts the presentation of a stimulus. Patients with schizophrenia perform poorly in working memory tasks that require the brief memory of a target location in space. This deficit indicates that persistent neural activity related to spatial locations may be impaired in the disease. At the circuit level, many studies have shown that NMDA receptors and the dopamine system are involved in both schizophrenia pathology and working memory-related persistent activity. In this Hypothesis and Theory article, we examine the possible connection between NMDA receptors, the dopamine system, and schizophrenia-linked working memory deficits. In particular, we focus on the dopamine breakdown product homocysteine (HCY), which is consistently elevated in schizophrenia patients. Our previous studies have shown that HCY strongly reduces the desensitization of NMDA currents. Here, we show that HCY likely affects NMDA receptors in brain regions that support working memory; this is because these areas favor dopamine breakdown over transport to clear dopamine from synapses. Finally, within the context of two NMDA-based computational models of working memory, we suggest a mechanism by which HCY could give rise to the working memory deficits observed in schizophrenia patients.

Serum Homocysteine and Behavioral and Psychological Symptoms of Dementia: Is There Any Correlation in Alzheimer's Disease?

Background

There are studies showing the relation between serum B12, folate and Behavioral and Psychological symptoms of Dementia (BPSD) in Alzheimer's disease (AD). Serum levels of these vitamins do not reflect actual disease status and therefore checking the serum Homocysteine level is considered a better test. Homocysteine has been found to be associated with cognitive impairment and various psychiatric disorders.

Purpose

This study was planned to identify the correlation between serum homocysteine levels and BPSD in AD patients.

Methods

AD patients (n = 18) and healthy controls (n = 18) were included in the study. Diagnosis of AD was confirmed using International Classification Disease-10. AD patients were assessed using Mini Mental Status Examination (MMSE), Clinical Dementia Rating scale (CDR), Global Deterioration scale (GDS), and Neuropsychiatric inventory (NPI). Healthy controls were assessed on MMSE and Mini International Neuropsychiatric Interview. Serum homocysteine, vitamin B12, and folate levels were measured in all study subjects.

Results

Patients with AD had statistically significant higher serum levels of homocysteine as compared to the control group, while the levels of vitamin B12 and folate did not differ significantly. There was statistically significant positive correlation of serum homocysteine levels with total NPI score as well as with NPI sub-domains particularly delusion, agitation/aggression, and depression/dysphoria. Serum homocysteine levels did not correlate significantly with MMSE, CDR, and GDS scores.

Conclusion

Correlation was observed between serum homocysteine levels and behavioral and psychological symptoms of AD. There is a possibility of etiological role, but the underlying pathophysiological mechanisms need to be elucidated. Whether patients will benefit or not with supplements of vitamin B12 and folate requires further research. This was a cross-sectional study and findings should not be generalized. Further prospective longitudinal studies with a large number of patients are needed.

Gender differences in C-reactive protein and homocysteine modulation of cognitive performance and real-world functioning in bipolar disorder

BACKGROUND

Cognitive and psychosocial impairment has been associated with increased levels of C-reactive protein (CRP) and homocysteine in bipolar disorder, but gender differences have seldom been studied.

METHODS

Two hundred and twenty-four bipolar outpatients were included. Cognitive performance was assessed through the Screen for Cognitive Impairment in Psychiatry (SCIP). Psychosocial functioning was evaluated using the Functioning Assessment Short Test (FAST) and the General Assessment of Functioning (GAF). Homocysteine and CRP levels were determined. Separate analyses were performed by gender. Partial correlations were calculated to test for associations between biomarkers and cognitive and psychosocial functioning. Hierarchical multiple regression was used to assess factors predicting cognitive and psychosocial functioning. Covariates were: age, education, duration of illness, hospital admissions, depressive symptoms, tobacco consumption, and BMI.

RESULTS

A better performance was noted in women in delayed verbal learning (p = 0.010), along with better occupational functioning (p = 0.027) and greater leisure time impairment (p = 0.034). In men, CRP and homocysteine levels were associated with psychosocial dysfunction (interpersonal relationships and financial functioning, respectively). In women, CRP levels correlated with cognitive performance (SCIP total raw score, immediate and delayed verbal learning, and verbal fluency). CRP was a predictor of cognitive performance in women only.

LIMITATIONS

The choice of the cognitive scale and covariates and the lack of a control group may be the main limitations.

CONCLUSIONS

A gender difference was found in biomarker modulation of cognition and psychosocial functioning. A gender-based approach to cognition and real-world functioning should be considered in bipolar disorder to ensure an optimal outcome.

Decreased serum pyridoxal levels in schizophrenia: meta-analysis and Mendelian randomization analysis

BACKGROUND

Alterations in one-carbon metabolism have been associated with schizophrenia, and vitamin B6 is one of the key components in this pathway.

METHODS

We first conducted a case-control study of serum pyridoxal levels and schizophrenia in a large Japanese cohort (n = 1276). Subsequently, we conducted a meta-analysis of association studies (n = 2125). Second, we investigated whether rs4654748, which was identified in a genome-wide association study as a vitamin B6-related single nucleotide polymorphism, was genetically implicated in patients with schizophrenia in the Japanese population (n = 10 689). Finally, we assessed the effect of serum pyridoxal levels on schizophrenia risk using a Mendelian randomization (MR) approach.

RESULTS

Serum pyridoxal levels were significantly lower in patients with schizophrenia than in controls, not only in our cohort, but also in the pooled data set of the meta-analysis of association studies (standardized mean difference -0.48, 95% confidence interval [CI] -0.57 to -0.39, p = 9.8 × 10-24). We failed to find a significant association between rs4654748 and schizophrenia. Furthermore, an MR analysis failed to find a causal relationship between pyridoxal levels and schizophrenia risk (odds ratio 0.99, 95% CI 0.65-1.51, p = 0.96).

LIMITATIONS

Food consumption and medications may have affected serum pyridoxal levels in our cross-sectional study. Sample size, number of instrumental variables and substantial heterogeneity among patients with schizophrenia are limitations of an MR analysis.

CONCLUSION

We found decreased serum pyridoxal levels in patients with schizophrenia in this observational study. However, we failed to obtain data supporting a causal relationship between pyridoxal levels and schizophrenia risk using the MR approach.

Natural Medicines for Psychotic Disorders: A Systematic Review

Patients with psychotic disorders regularly use natural medicines, although it is unclear whether these are effective and safe. The aim of this study was to provide an overview of evidence for improved outcomes by natural medicines. A systematic literature search was performed through Medline, PsycINFO, CINAHL, and Cochrane until May 2015. In 110 randomized controlled trials, evidence was found for glycine, sarcosine, N-acetylcysteine, some Chinese and ayurvedic herbs, ginkgo biloba, estradiol, and vitamin B6 to improve psychotic symptoms when added to antipsychotics. Ginkgo biloba and vitamin B6 seemed to reduce tardive dyskinesia and akathisia. Results on other compounds were negative or inconclusive. All natural agents, except reserpine, were well tolerated. Most study samples were small, study periods were generally short, and most results need replication. However, there is some evidence for beneficial effects of certain natural medicines.

Biochemical, physiological and clinical effects of l-methylfolate in schizophrenia: a randomized controlled trial

Folic acid supplementation confers modest benefit in schizophrenia, but its effectiveness is influenced by common genetic variants in the folate pathway that hinder conversion to its active form. We examined physiological and clinical effects of l-methylfolate, the fully reduced and bioactive form of folate, in schizophrenia. In this randomized, double-blind trial, outpatients with schizophrenia (n=55) received l-methylfolate 15 mg or placebo for 12 weeks. Patients were maintained on stable doses of antipsychotic medications. The pre-defined primary outcome was change in plasma methylfolate at 12 weeks. Secondary outcomes included change in symptoms (Positive and Negative Syndrome Scale (PANSS), Scale for Assessment of Negative Symptoms, Calgary Depression Scale for Schizophrenia), cognition (Measurement and Treatment Research to Improve Cognition in Schizophrenia composite) and three complementary magnetic resonance imaging measures (working memory-related activation, resting connectivity, cortical thickness). Primary, mixed model, intent-to-treat analyses covaried for six genetic variants in the folate pathway previously associated with symptom severity and/or response to folate supplementation. Analyses were repeated without covariates to evaluate dependence on genotype. Compared with placebo, l-methylfolate increased plasma methylfolate levels (d=1.00, P=0.0009) and improved PANSS Total (d=0.61, P=0.03) as well as PANSS Negative and General Psychopathology subscales. Although PANSS Total and General Psychopathology changes were influenced by genotype, significant PANSS Negative changes occurred regardless of genotype. No treatment differences were seen in other symptom rating scales or cognitive composite scores. Patients receiving l-methylfolate exhibited convergent changes in ventromedial prefrontal physiology, including increased task-induced deactivation, altered limbic connectivity and increased cortical thickness. In conclusion, l-methylfolate supplementation was associated with salutary physiological changes and selective symptomatic improvement in this study of schizophrenia patients, warranting larger clinical trials. ClinicalTrials.gov, NCT01091506.

Pyridoxamine: A novel treatment for schizophrenia with enhanced carbonyl stress

AIM

The aim of this clinical trial was to obtain proof of concept for high-dose pyridoxamine as a novel treatment for schizophrenia with enhanced carbonyl stress.

METHODS

Ten Japanese schizophrenia patients with high plasma pentosidine, which is a representative biomarker of enhanced carbonyl stress, were recruited in a 24-week, open trial in which high-dose pyridoxamine (ranging from 1200 to 2400 mg/day) was administered using a conventional antipsychotic regimen. Main outcomes were the total change in Positive and Negative Syndrome Scale score and the Brief Psychiatric Rating Scale score from baseline to end of treatment at week 24 (or at withdrawal).

RESULTS

Decreased plasma pentosidine levels were observed in eight patients. Two patients showed marked improvement in their psychological symptoms. A patient who harbors a frameshift mutation in the Glyoxalase 1 gene also showed considerable reduction in psychosis accompanied with a moderate decrease in plasma pentosidine levels. A reduction of greater than 20% in the assessment scale of drug-induced Parkinsonism occurred in four patients. Although there was no severe suicide-related ideation or behavior, Wernicke's encephalopathy-like adverse drug reactions occurred in two patients and were completely suppressed by thiamine supplementation.

CONCLUSION

High-dose pyridoxamine add-on treatment was, in part, effective for a subpopulation of schizophrenia patients with enhanced carbonyl stress. Further randomized, placebo-controlled trials with careful monitoring will be required to validate the efficacy of high-dose pyridoxamine for these patients.

S-Adenosyl Methionine and Transmethylation Pathways in Neuropsychiatric Diseases Throughout Life

S-Adenosyl methionine (SAMe), as a major methyl donor, exerts its influence on central nervous system function through cellular transmethylation pathways, including the methylation of DNA, histones, protein phosphatase 2A, and several catecholamine moieties. Based on available evidence, this review focuses on the lifelong range of severe neuropsychiatric and neurodegenerative diseases and their associated neuropathologies, which have been linked to the deficiency/load of SAMe production or/and the disturbance in transmethylation pathways. Also included in this review are the present-day applications of SAMe in the treatment in these diseases in each age group.

Antioxidant and anti-inflammatory nutrient status, supplementation, and mechanisms in patients with schizophrenia

Over 50 million people around the world suffer from schizophrenia, a severe mental illness characterized by misinterpretation of reality. Although the exact causes of schizophrenia are still unknown, studies have indicated that inflammation and oxidative stress may play an important role in the etiology of the disease. Pro-inflammatory cytokines are crucial for normal central nervous development and proper functioning of neural networks and neurotransmitters. Patients with schizophrenia tend to have abnormal immune activation resulting in elevated pro-inflammatory cytokine levels, ultimately leading to functional brain impairments. Patients with schizophrenia have also been found to suffer from oxidative stress, a result of an imbalance between the production of free radicals and the ability to detoxify their harmful effects. Furthermore, inflammation and oxidative stress are implicated to be related to the severity of psychotic symptoms. Several nutrients are known to have anti-inflammatory and antioxidant functions through various mechanisms in our body. The present review evaluates studies and literature that address the status and supplementation of omega-3 polyunsaturated fatty acids, vitamin D, B vitamins (B6, folate, B12), vitamin E, and carotenoids in different stages of schizophrenia. The possible anti-inflammatory and antioxidant mechanisms of action of each nutrient are discussed.

The effects of vitamin and mineral supplementation on symptoms of schizophrenia: a systematic review and meta-analysis

BACKGROUND

When used as an adjunctive with antipsychotics, certain vitamins and minerals may be effective for improving symptomatic outcomes of schizophrenia, by restoring nutritional deficits, reducing oxidative stress, or modulating neurological pathways.

METHOD

We conducted a systematic review of all randomized controlled trials (RCTs) reporting effects of vitamin and/or mineral supplements on psychiatric symptoms in people with schizophrenia. Random-effects meta-analyses were used to calculate the standardized mean difference between nutrient and placebo treatments.

RESULTS

An electronic database search in July 2016 identified 18 eligible RCTs, with outcome data for 832 patients. Pooled effects showed that vitamin B supplementation (including B6, B8 and B12) reduced psychiatric symptoms significantly more than control conditions [g = 0.508, 95% confidence interval (CI) 0.01-1.01, p = 0.047, I 2 = 72.3%]. Similar effects were observed among vitamin B RCTs which used intention-to-treat analyses (g = 0.734, 95% CI 0.00-1.49, p = 0.051). However, no effects of B vitamins were observed in individual domains of positive and negative symptoms (both p > 0.1). Meta-regression analyses showed that shorter illness duration was associated with greater vitamin B effectiveness (p = 0.001). There were no overall effects from antioxidant vitamins, inositol or dietary minerals on psychiatric symptoms.

CONCLUSIONS

There is preliminary evidence that certain vitamin and mineral supplements may reduce psychiatric symptoms in some people with schizophrenia. Further research is needed to examine how the benefits of supplementation relate to nutrient deficits and the impact upon underlying neurobiological pathways, in order to establish optimal nutrient formulations for improving clinical outcomes in this population. Future studies should also explore the effects of combining beneficial nutrients within multi-nutrient formulas.

[Psychopathological characteristics and social functioning of the schizophrenic patients with the T allele of the MTHFR677C>T polymorphism]

AIM

To compare the severity of psychopathological symptoms and characteristics of personal and social functioning in patients with schizophrenia, carriers of different alleles of the MTHFR677C>T polymorphism.

MATERIAL AND METHODS

One hundred and fifty patients diagnosed with schizophrenia were genotyped for the MTHFR677C>T polymorphism, some of them were examined using psychometric scales and tests (PANSS, SANS, PSP, CDSS, a battery of cognitive tests etc).

RESULTS AND CONCLUSION

Patients with the MTHFR677T variant had greater severity of negative symptoms regardless of psychometric instruments used in the study, greater severity of schizophrenia disorder in whole measured with the PANSS General psychopathological symptoms subscale, higher scores on the PANSS cognitive cluster and lower levels of personal and social functioning measured with the PSP compared to the patients with the MTHFR677CС genotype. The results of psychometric testing are in line with significant differences of MTHFR677T allele carriers from those with the MTHFR677CС genotype in the number of disable patients and the use of different types of psychiatric services. The differences were not related to sex, age, illness duration and depressive symptoms measured with CDSS and PANSS «depression/anxiety» factor.

Lower folate levels in schizophrenia: A meta-analysis

This meta-analysis aimed to estimate the association between folate level and schizophrenia in order to provide the evidence for the treatment of schizophrenia. Data were extracted from all the studies meeting our inclusion and exclusion criteria. The association between the folate level and schizophrenia was evaluated by the standardized mean difference (SMD) and 95% confidence interval (CI). The 20 published articles of our meta-analysis included 1463 (53.4%) cases and 1276 (46.6%) controls. The folate level was significantly lower in schizophrenia cases than in healthy controls. Subgroup analysis showed the folate level was lower in cases from Asia subgroup than in healthy controls. Sensitivity analysis showed that the current results were credible and reliable and the funnel plots indicated no publication bias in our meta-analysis. Our study indicates that schizophrenia patients may have lower folate levels. More epidemiological and laboratory studies are still needed to confirm whether it is necessary to supplement folate in schizophrenia patients.

Effect of folic acid on oxidative stress and behavioral changes in the animal model of schizophrenia induced by ketamine

Recent studies have shown benefits for the supplementation of folic acid in schizophrenic patients. The aim of this study was to evaluate the effects of folic acid addition on adult rats, over a period of 7 or 14 days. It also sets out to verify any potential protective action using an animal model of schizophrenia induced by ketamine, in behavioral and biochemical parameters. This study used two protocols (acute and chronic) for the administration of ketamine at a dose of 25 mg/kg (i.p.). The folic acid was given by oral route in doses of 5, 10 and 50 mg/kg, once daily, for 7 and/or 14 days in order to compare the protective effects of folic acid. Thirty minutes after the last administration of ketamine, the locomotor and social interaction activities were evaluated, and immediately the brain structure were removed for biochemical analysis. In this study, ketamine was administered in a single dose or in doses over the course of 7 days increasing the animal's locomotion. This study showed that the administration of folic acid over 7 days was unable to prevent hyper locomotion. In contrast, folic acid (10 and 50 mg/kg) administrated over a period of 14 days, was able to partially prevent the hyper locomotion. Our data indicates that both acute and chronic administrations of ketamine increased the time to first contact between the animals, while the increased latency for social contact was completely prevented by folic acid (5, 10 and 50 mg/kg). Chronic and acute administrations of ketamine also increased lipid peroxidation and protein carbonylation in brain. Folic acid (10 and 50 mg/kg) supplements showed protective effects on the oxidative damage found in the different brain structures evaluated. All together, the results indicate that nutritional supplementation with folic acid provides promising results in an animal model of schizophrenia induced by ketamine.

Homocysteine and cognition: A systematic review of 111 studies

BACKGROUND

Elevated plasma homocysteine ​​(Hcy) levels have been associated with cognitive dysfunction in a wide range of conditions. The aim of this review is to establish which cognitive domains and populations are the most affected.

METHODS

We systematically review the literature and consider all articles that showed any relationship between plasma Hcy levels and scores achieved on cognitive performance tests in both, the general population and patients suffering from central nervous system disorders and other diseases. When effect sizes were available and combinable, several meta-analyses were performed.

RESULTS

We found 111 pertinent articles. There were 24 cohort studies, 18 randomized trials, 21 case-control studies, and 48 cross-sectional studies. This review reveals a positive trend between cognitive decline and increased plasma Hcy concentrations in general population and in patients with cognitive impairments. Results from the meta-analyses also confirm this trend. Treatment with vitamin supplementation fails to show a reduction in cognitive decline.

DISCUSSION

Further investigations are warranted to clarify this relationship. Earlier detection of the elevated Hcy levels may be an effective intervention to prevent cognitive impairment and dementia.

Metabolic dysregulation in first-episode schizophrenia patients with respect to genetic variation in one-carbon metabolism

The aim of this study was to investigate the prevalence of metabolic disturbances in patients with first-episode schizophrenia (FES) and test the hypothesis that genetic variation in one-carbon metabolism may account for metabolic dysregulation in early psychosis. We measured fasting glucose, lipid profile parameters, homocysteine, folate and vitamin B12 in 135 patients with FES and 146 healthy controls (HCs). Polymorphisms in the following genes were determined: MTHFR (C677T and A1298C), MTHFD1 (G1958A), MTRR (A66G) and BHMT (G742A). Serum levels of folate and high-density lipoproteins (HDL) were significantly lower in patients with FES compared to HCs. In turn, serum levels of homocysteine and triglycerides were significantly higher in patients with FES than in HCs. Prevalence of hyperhomocysteinemia, low folate and HDL levels together with dyslipidemia was significantly higher in patients with FES compared to HCs. Higher homocysteine levels, lower vitamin B12 levels and the presence of metabolic syndrome were associated with higher severity of negative symptoms. None of studied polymorphisms was associated with schizophrenia risk. Several associations between studied polymorphisms and cardio-metabolic parameters were found. None of them remained significant after Bonferroni correction. Our results indicate that metabolic dysregulation in patients with FES is not associated with genetic variation in one-carbon metabolism.

Role of MTHFR C677T gene polymorphism in the susceptibility of schizophrenia: An updated meta-analysis

Methylenetetrahydrofolate reductase (MTHFR) is the key enzyme of folate/homocysteine metabolic pathway. C677T polymorphism of MTHFR gene was reported as risk factor for congenital defects, metabolic and neuropsychiatric disorders. Numerous case-control studies investigated C677T polymorphism as risk factor for schizophrenia but results of these studies were contradictory. To draw a conclusion, a meta-analysis of all available case-control studies was performed. PubMed, Google Scholar, Springer Link and Elsevier databases were searched for eligible case-control studies. Pooled odds ratio with 95%CI was used as an association measure and all statistical analyses were performed by Open Meta-Analyst and MIX software. Total 38 studies with 10,069 cases and 13,372 controls were included in the present meta-analysis. Results of meta-analysis showed significant associated between C677T polymorphism and risk of schizophrenia (ORTvsC=1.18, 95%CI=1.10-1.27, p=<0.001; ORCTvsCC=1.10, 95%CI=1.04-1.17, p=<0.001; ORTTvsCC=1.40, 95%CI=1.20-1.64, p=<0.001; ORTT+CTvsCC=1.19, 95%CI=1.09-1.30, p=<0.001). We also performed subgroup and sensitivity analyses. Subgroup analysis was done according to ethnicity and significant association was found between C677T polymorphism and risk of schizophrenia in all three ethnic populations-African (OR=2.51; 95%CI=1.86-3.40; p=<0.001), Asian (OR=1.21; 95%CI=1.10-1.33; p=<0.001) and Caucasian (OR=1.07; 95%CI=1.01-1.14; p=0.01). In conclusion the results of the present meta-analysis suggested that the MTHFR C677T polymorphism is a risk factor for schizophrenia.

Homocysteine levels in schizophrenia patients newly admitted to an acute psychiatric ward

OBJECTIVE

After the discovery of 'homocystinuria syndrome', many studies have suggested that high blood levels of homocysteine may be associated with schizophrenia. The aim of this study was to analyse the association between hyperhomocysteinaemia and schizophrenia.

METHODS

In a population of inpatients suffering from exacerbated schizophrenic disorders (N=100), we evaluated homocysteine levels the day after their admission to an acute psychiatric ward and compared it with that of a non-patient control group (N=110), matched for age and gender. We statistically analysed the correlation between homocysteine levels and selected variables: gender, age, years of illness and number of previous psychiatric admissions as well as Brief Psychiatric Rating Scale, Positive Negative Syndrome Scale and Global Assessment Functioning (GAF) Scores.

RESULTS

We observed elevated homocysteine levels (an increase of 7.84 µM on average per patient) in 32% of the patients, but we did not find any statistically significant difference between the homocysteine levels of our patients and controls. Hyperhomocysteinaemia presented a positive statistically significant correlation with years of illness (p<0.005) and a negative statistically significant correlation with GAF score (p<0.001), but not with other clinical variables.

CONCLUSIONS

Hyperhomocysteinaemia, which occurred in our schizophrenia patients with poor social and relational functioning after many years of illness, could represent an effect of altered lifestyle due to psychosis, but not a specific marker for schizophrenia.

Improvement of Psychotic Symptoms and the Role of Tissue Plasminogen Activator

Tissue plasminogen activator (tPA) mediates a number of processes that are pivotal for synaptogenesis and remodeling of synapses, including proteolysis of the brain extracellular matrix, degradation of adhesion molecules, activation of neurotrophins, and activation of the N-methyl-d-aspartate receptor. Abnormalities in these processes have been consistently described in psychotic disorders. In this paper, we review the physiological roles of tPA, focusing on conditions characterized by low tPA activity, which are prevalent in schizophrenia. We then describe how tPA activity is influenced by lifestyle interventions and nutritional supplements that may ameliorate psychotic symptoms. Next, we analyze the role of tPA in the mechanism of action of hormones and medications effective in mitigating psychotic symptoms, such as pregnenolone, estrogen, oxytocin, dopamine D3 receptor antagonists, retinoic acid, valproic acid, cannabidiol, sodium nitroprusside, N-acetyl cysteine, and warfarin. We also review evidence that tPA participates in the mechanism by which electroconvulsive therapy and cigarette smoking may reduce psychotic symptoms.

Evaluation of an association between plasma total homocysteine and schizophrenia by a Mendelian randomization analysis

BACKGROUND

The results of meta-analyses conducted by previous association studies between total homocysteine and schizophrenia suggest that an elevated total homocysteine level is a risk factor for schizophrenia. However, observational studies have potential limitations, such as confounding and reverse causation. In the present study, we evaluated a causal relationship between plasma total homocysteine and schizophrenia by conducting a Mendelian randomization analysis.

METHODS

We used the MTHFR C677T polymorphism as an instrumental variable, which affects the plasma total homocysteine levels. To calculate the risk estimate for the association of this single nucleotide polymorphism (SNP) with schizophrenia, we conducted a meta-analysis of case-control studies that comprise a total of 11,042 patients with schizophrenia and 14,557 control subjects. We obtained an estimate for the association of this SNP with the plasma total homocysteine levels from a meta-analysis of genome-wide association studies comprising 44,147 individuals.

RESULTS

By combining these two estimates, we demonstrated a significant effect of the plasma total homocysteine on schizophrenia risk, representing an OR of 2.15 (95 % CI = 1.39-3.32; p = 5.3 x 10(-4)) for schizophrenia per 1-SD increase in the natural log-transformed plasma total homocysteine levels.

CONCLUSIONS

We provided evidence of a causal relationship between the plasma total homocysteine and schizophrenia, and this result will add insight into the pathology and treatment of schizophrenia.

Drug repurposing and emerging adjunctive treatments for schizophrenia

INTRODUCTION

Schizophrenia is a frequent disorder, which substantially impairs patients' quality of life. Moreover, the burden of illness for patients, their families and for the society, in general, is substantial. Nevertheless, the understanding of the pathophysiology of this syndrome, concise diagnostic methods and more effective and tolerable treatments are still lacking. Thus, innovative approaches and the exploration of new territories are required.

AREAS COVERED

An overview of repurposed drugs and emerging treatments for schizophrenia is presented, focusing on randomized, controlled trials and meta-analyses.

EXPERT OPINION

Despite many years of drug research, several needs in the treatment of schizophrenia including the safety and tolerability, stage-dependent and personalized approaches, as well as drug delivery and sustainability have not been addressed sufficiently. Given the current failure of a number of mechanistically new drugs, repurposed compounds may serve as alternative and/or adjunctive agents for schizophrenic patients and for treatment refractory patients in particular. Anti-inflammatory drugs (e.g., acetylsalicylic acid, celecoxib and minocycline), as well as N-acetylcysteine, a precursor of the major antioxidant glutathione, hormones (e.g., estrogen, raloxifene and oxytocin), glutamatergic (e.g., glycine and d-serine) and nicotinergic compounds, 'nutraceuticals' (e.g., ω-3 fatty acids) and cannabidiol, an endocannabinoidmodulator, represent promising agents in this field.