Polymorphism of Transferrin Gene Impacts the Mediating Effects of Psychotic Symptoms on the Relationship between Oxidative Stress and Cognition in Patients with Chronic Schizophrenia

A series of studies indicated that iron distribution that partly derives from transferrin-bound iron in the peripheral nervous system in the brain may act in processes such as myelination and brain development. However, the relationship between schizophrenia, its psychotic symptoms, and the transferrin (TF) gene has not been systematically explored. Our study aimed to investigate how a particular polymorphism of the transferrin gene, rs3811655, affects the superoxide dismutase (SOD), malondialdehyde (MDA), psychotic symptoms, cognition, or the mediation model between antioxidant enzymes and cognition via symptoms. A total of 564 patients with chronic schizophrenia and 468 healthy control subjects were recruited. The psychotic symptoms and cognition were assessed by the Positive and Negative Syndrome Scale (PANSS) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), respectively. Furthermore, the serum SOD, MDA activity, and transferrin gene polymorphism were measured in patients. Our results demonstrated that patients with the G allele possessed more severe negative symptoms, worse cognitive performance with respect to attention, and higher serum Mn-SOD activity. Additionally, the rs3811655 polymorphism may act as a moderator in the association between Cu/Zn-SOD activity and cognition, as well as psychotic symptoms in patients suffering from schizophrenia. According to this study, the single nucleotide polymorphism (SNP) rs3811655 polymorphism may fail to contribute to the susceptibility of schizophrenia in an individual but is involved in the iron-induced oxidative stress disturbance and cognitive impairment in schizophrenia. This deepens our understanding of the critical role of iron-induced oxidative stress that might underlie the pathophysiology of schizophrenia.

Phenomenology of the COVID-19 Pandemic Experience in Patients Suffering from Chronic Schizophrenia—A Qualitative Analysis

Many studies have shown that the COVID-19 pandemic can have a great influence on mental health. However, there is still not enough research to fully understand how people suffering from schizophrenia experience crisis situations such as a pandemic. This qualitative study aims to explore this subject. Ten outpatients suffering from schizophrenia were interviewed in a semi-structured format using an interview designed by the authors for the purpose of this study. The interviews were transcribed, and a conventional qualitative content analysis was conducted. The general themes identified in the content analysis were organized into four categories: first reactions to information about the pandemic; subjective assessment of the pandemic’s impact on patients’ mental health; patients’ attitudes towards the temporary limitations and lockdowns; psychiatric treatment and psychotherapy during the pandemic. A variety of different experiences were observed, but the general conclusion arising from the study suggests that the majority of the interviewed patients coped quite well with the pandemic and that the observed reactions were similar to the reactions of other groups described in the literature. The study also confirmed the importance of the continuity of psychiatric care for patients with schizophrenia.

A Metabolomics Study of Serum in Hospitalized Patients With Chronic Schizophrenia

Purpose: Metabolomics has attracted attention as a new method for understanding the molecular mechanisms of psychiatric disorders. Current metabolomics technology allows us to measure over hundreds of metabolites at a time and is a useful indicator of the consequences of complex and continuous changes in metabolic profiles due to the execution of genomic information and external factors of biological activity. Therefore, metabolomics is imperative to the discovery of biomarkers and mechanisms associated with pathophysiological processes. In this study, we investigated metabolites changes in hospitalized patients with chronic schizophrenia compared to that in healthy controls, and examined the correlations between the metabolites and psychiatric symptoms.Patients and Methods: Thirty patients with schizophrenia and ten healthy controls participated in this study between September 2019 and June 2020. The mean duration of disease in patients with schizophrenia was 26 years. Clinical and neuropsychiatric symptoms of patients with schizophrenia were assessed using the Positive and Negative Syndrome Scale (PANSS). Metabolomics was conducted using Capillary Electrophoresis Fourier Transform Mass Spectrometry (CE-FTMS), using serum samples from patients with schizophrenia and healthy controls. Metabolomics assigned a candidate compound to the 446 (cation 279, anion 167) peaks. Hierarchical cluster analysis (HCA), principal component analysis (PCA), logistic regression analysis, receiver operating characteristic (ROC) analysis, and linear regression analysis were used to analyze the metabolites changes, identifying the disease and the relationship between metabolites and psychiatric symptoms.Results: HCA showed that approximately 60% of metabolites had lower peak values in patients with schizophrenia than in healthy controls. Glutamate metabolism and the urea cycle had the highest proportions in the metabolic pathway, which decreased in patients with schizophrenia. PCA showed a clear separation between patients with schizophrenia and healthy controls in the first principal component (the contribution ratio of the first principal component was 15.9%). Logistic regression analysis suggested that the first principal component was a predictor of disease (odds = 1.36, 95%CI = 1.11–1.67, p = 0.0032). ROC analysis showed a sensitivity of 93% and a specificity of 100% for the diagnosis of schizophrenia with a cut-off value of the first principal component; −3.33 (AUC = 0.95). We extracted the high factor loading for the first principal component. Gamma-glutamyl-valine (γ-Glu-Val) was significantly negatively correlated with PANSS total scores (r = −0.45, p = 0.012) and PANSS general scores (r = −0.49, p = 0.0055). Gamma-glutamyl-phenylalanine (γ-Glu-Phe) was significantly negatively correlated with PANSS total score (r = −0.40, p = 0.031) and PANSS general score (r = −0.41, p = 0.025). Tetrahydrouridine was significantly positively correlated with PANSS negative scores (r = 0.53, p = 0.0061).Conclusion: Metabolites changes in hospitalized patients with chronic schizophrenia showed extensive and generalized declines. Glutamate metabolism and the urea cycle had the highest proportions in the metabolic pathway, which decreased in the schizophrenia group. Metabolomic analysis was useful to identify chronic schizophrenia. Some glutamate compound metabolites had a relationship with psychiatric symptoms.

Efficacy of Spironolactone As an Adjunctive Therapy to Risperidone to Improve Symptoms of Schizophrenia; A Double-Blind, Randomized, Placebo-Controlled, Clinical Trial

Objective: Spironolactone (C24H32O4S), a potent mineralocorticoid receptor (MR) inhibitor, is a potassium-sparing diuretic that is traditionally used to treat fluid build-up in the body or for its anti-androgenic properties. This study is a double-blind, placebo-controlled, randomized clinical trial assessing the beneficial effects of spironolactone in addition to risperidone in improving negative symptoms of schizophrenia. Method: 40 patients with chronic schizophrenia, aged 18–60 years, were assigned to two groups: risperidone + spironolactone or risperidone + placebo. Risperidone was administered to both the spironolactone and placebo groups with a dose up to 6 mg/day throughout the trial. Spironolactone (C24H32O4S) was ordered 100 mg/day for the full 8-week course of the study. Patients were rated on the Positive and Negative Syndrome Scale (PANSS) at four time points: baseline, weeks two, four, and eight. The PANSS negative subscale score was the main objective. Results: PANSS negative, positive, and total scores showed significantly greater improvements in the spironolactone relative to the placebo group from baseline to the trial endpoint (P (Cohen’s d): 0.004 (0.96), 0.007 (0.90), and 0.042 (0.66), respectively). Similarly, ANOVA also presented significant time × treatment interaction effect for spironolactone on PANSS negative (F = 9.04; ηp2 = 0.19; df = 1.38; P = 0.002), positive (F = 3.43; ηp2 = 0.08; df = 2.72; P = 0.023), and total (F = 3.94; ηp2 = 0.09; df = 2.05; P = 0.022) scores. However, spironolactone did not cause significant decrease in the general psychiatric pathology score of PANSS. Conclusion: Our findings suggest the efficacy and safety of spironolactone as an adjunctive therapy to risperidone in improving the symptoms of schizophrenia.

Investigating the Relationships of P3b with Negative Symptoms and Neurocognition in Subjects with Chronic Schizophrenia

Neurocognitive deficits and negative symptoms (NS) have a pivotal role in subjects with schizophrenia (SCZ) due to their impact on patients’ functioning in everyday life and their influence on goal-directed behavior and decision-making. P3b is considered an optimal electrophysiological candidate biomarker of neurocognitive impairment for its association with the allocation of attentional resources to task-relevant stimuli, an important factor for efficient decision-making, as well as for motivation-related processes. Furthermore, associations between P3b deficits and NS have been reported. The current research aims to fill the lack of studies investigating, in the same subjects, the associations of P3b with multiple cognitive domains and the expressive and motivation-related domains of NS, evaluated with state-of-the-art instruments. One hundred and fourteen SCZ and 63 healthy controls (HCs) were included in the study. P3b amplitude was significantly reduced and P3b latency prolonged in SCZ as compared to HCs. In SCZ, a positive correlation was found between P3b latency and age and between P3b amplitude and the Attention-vigilance domain, while no significant correlations were found between P3b and the two NS domains. Our results indicate that the effortful allocation of attention to task-relevant stimuli, an important component of decision-making, is compromised in SCZ, independently of motivation deficits or other NS.

Association between clinical symptoms and apolipoprotein A1 or apolipoprotein B levels is regulated by apolipoprotein E variant rs429358 in patients with chronic schizophrenia

Background The apolipoprotein E (ApoE) gene polymorphisms are correlated with blood lipid levels and several neuropsychiatric symptoms. Therefore, this study aimed to examine whether the ApoE rs429358 affected the development and clinical symptoms of schizophrenia and to explore the relationship between apolipoproteins levels and clinical symptoms. Methods The ApoE rs429358 was genotyped using a case–control design. The Positive and Negative Syndrome Scale (PANSS) was employed to evaluate the psychopathology of all patients. Results A total of 637 patients with schizophrenia and 467 healthy controls were recruited. We found no significant differences in the genotype and allele distribution between the patient and control groups. A significant correlation between PANSS negative symptoms and ApoA1 levels (p = 0.048) or ApoB levels (p = 0.001) was found in patients with schizophrenia, which was also confirmed by linear regression analyses (p = 0.048 vs. p = 0.001). Interestingly, only in the T homozygote group, ApoA1 and ApoB levels were predictors of the PANSS negative symptom score (p = 0.008 vs. p = 0.012), while in the C allele carrier group, no correlation was observed. Conclusions This study found that the levels of ApoA1 and ApoB were negatively associated with negative symptoms of patients with schizophrenia. Furthermore, the association between ApoA1 or ApoB levels and psychopathology of schizophrenia was regulated by ApoE rs429358.