Long-term antipsychotic treatments and crossover studies in rats: differential effects of typical and atypical agents on the expression of antioxidant enzymes and membrane lipid peroxidation in rat brain

Investigation of the effects of oxidative stress, inflammation on the pathway of tryptophan/kynurenine in OCD

OBJECTIVES

Recent studies have shown that the distribution of the tryptophan/kynurenine pathway (KP) plays a role in the development of obsessive-compulsive disorder (OCD). We aimed to reveal the relationship between CYP1A1 rs464903 and aryl hydrocarbon receptor (AhR) rs10249788 associated with the KP and interferon gamma (IFN γ) and oxidative stress in OCD.

METHODS

In our study, the serum and DNAs of 150 samples, including 100 OCD patients and 50 controls, were used. The activity of glutathione peroxidase (GSH-Px), and the levels of IFN γ, thiobarbituric acid reactive substances (TBARS), tryptophan, and kynurenine were determined by biochemical methods. AhR rs10249788 and cytochrome P450 family CYP1A1 rs4646903, which interact directly with the KP, were analysed by polymerase chain reaction followed by restriction fragment length polymorphism. P < 0.05 was considered statistically significant.

RESULT

There were no significant differences between groups in CYP1A1 rs4646903 and AhR rs10249788 while tryptophan and IFN γ were found to be higher in controls (p < 0.001, for both), and TBARS and indolamine-2,3-dioxygenase were found to be higher in OCD (p < 0.001, for both). There were significant correlations between IFN γ and TBARS and GSH-Px (p = 0.028, p = 0.020, respectively) in the OCD group.

CONCLUSIONS

For the first time studied in OCD, it has been shown that IFN γ, tryptophan, oxidative stress parameters, and gene variants of CYP1A1 rs4646903 anAhR rs10249788 are shown effective on the KP.

Receptor-Independent Therapies for Forensic Detainees with Schizophrenia-Dementia Comorbidity

Forensic institutions throughout the world house patients with severe psychiatric illness and history of criminal violations. Improved medical care, hygiene, psychiatric treatment, and nutrition led to an unmatched longevity in this population, which previously lived, on average, 15 to 20 years shorter than the public at large. On the other hand, longevity has contributed to increased prevalence of age-related diseases, including neurodegenerative disorders, which complicate clinical management, increasing healthcare expenditures. Forensic institutions, originally intended for the treatment of younger individuals, are ill-equipped for the growing number of older offenders. Moreover, as antipsychotic drugs became available in 1950s and 1960s, we are observing the first generation of forensic detainees who have aged on dopamine-blocking agents. Although the consequences of long-term treatment with these agents are unclear, schizophrenia-associated gray matter loss may contribute to the development of early dementia. Taken together, increased lifespan and the subsequent cognitive deficit observed in long-term forensic institutions raise questions and dilemmas unencountered by the previous generations of clinicians. These include: does the presence of neurocognitive dysfunction justify antipsychotic dose reduction or discontinuation despite a lifelong history of schizophrenia and violent behavior? Should neurolipidomic interventions become the standard of care in elderly individuals with lifelong schizophrenia and dementia? Can patients with schizophrenia and dementia meet the Dusky standard to stand trial? Should neurocognitive disorders in the elderly with lifelong schizophrenia be treated differently than age-related neurodegeneration? In this article, we hypothesize that gray matter loss is the core symptom of schizophrenia which leads to dementia. We hypothesize further that strategies to delay or stop gray matter depletion would not only improve the schizophrenia sustained recovery, but also avert the development of major neurocognitive disorders in people living with schizophrenia. Based on this hypothesis, we suggest utilization of both receptor-dependent and independent therapeutics for chronic psychosis.

Increased levels of lipid and protein oxidation in rat prefrontal cortex after treatment by lithium, valproic acid, and olanzapine

Oxidative stress is widely accepted to contribute to the pathogenesis of several psychiatric diseases. Many antipsychotic drugs and mood stabilizers act through restoration of the dysregulated oxidative homeostasis in the brain. However, the long-term effect of these drugs per se in terms of their potential to interfere with the oxidative status in the brain remains largely controversial. The present study aimed to investigate the sole effect of three commonly used psychoactive drugs, lithium, valproic acid, and olanzapine, on lipid and protein oxidation status in the prefrontal cortex of healthy rats. A total of 80 adult male albino Wistar rats were used, and groups were treated with saline (control), lithium, valproic acid, or olanzapine daily for 30 days. Following sacrification, right prefrontal cortexes were dissected and homogenized. Lipid peroxidation (LPO) and protein oxidation (AOPP) assays were performed by ELISA. LPO levels were significantly higher in lithium and valproic acid-treated rats by 45% and 40%, respectively. Olanzapine treatment caused a mild 26% increase in LPO levels, but the effect was non-significant. Lithium, valproic acid, and olanzapine treatments significantly increased AOPP levels by 58%, 54%, and 36.5%, respectively. There was a strong positive correlation between the lipid peroxidation and protein oxidation levels. Our results call attention to the need to consider the pro-oxidative capacity of antipsychotic drugs per se and their potential to disturb the oxidative homeostasis in the brain during long-term medication for psychiatric diseases.

Hypothalamic JNK1-hepatic fatty acid synthase axis mediates a metabolic rewiring that prevents hepatic steatosis in male mice treated with olanzapine via intraperitoneal: Additional effects of PTP1B inhibition

Olanzapine (OLA), a widely used second-generation antipsychotic (SGA), causes weight gain and metabolic alterations when administered orally to patients. Recently, we demonstrated that, contrarily to the oral treatment which induces weight gain, OLA administered via intraperitoneal (i.p.) in male mice resulted in body weight loss. This protection was due to an increase in energy expenditure (EE) through a mechanism involving the modulation of hypothalamic AMPK activation by higher OLA levels reaching this brain region compared to those of the oral treatment. Since clinical studies have shown hepatic steatosis upon chronic treatment with OLA, herein we further investigated the role of the hypothalamus-liver interactome upon OLA administration in wild-type (WT) and protein tyrosine phosphatase 1B knockout (PTP1B-KO) mice, a preclinical model protected against metabolic syndrome. WT and PTP1B-KO male mice were fed an OLA-supplemented diet or treated via i.p. Mechanistically, we found that OLA i.p. treatment induces mild oxidative stress and inflammation in the hypothalamus in a JNK1-independent and dependent manner, respectively, without features of cell dead. Hypothalamic JNK activation up-regulated lipogenic gene expression in the liver though the vagus nerve. This effect concurred with an unexpected metabolic rewiring in the liver in which ATP depletion resulted in increased AMPK/ACC phosphorylation. This starvation-like signature prevented steatosis. By contrast, intrahepatic lipid accumulation was observed in WT mice treated orally with OLA; this effect being absent in PTP1B-KO mice. We also demonstrated an additional benefit of PTP1B inhibition against hypothalamic JNK activation, oxidative stress and inflammation induced by chronic OLA i.p. treatment, thereby preventing hepatic lipogenesis. The protection conferred by PTP1B deficiency against hepatic steatosis in the oral OLA treatment or against oxidative stress and neuroinflammation in the i.p. treatment strongly suggests that targeting PTP1B might be also a therapeutic strategy to prevent metabolic comorbidities in patients under OLA treatment in a personalized manner.

Brain Structural Changes in Schizophrenia Patients Compared to the Control: An MRI-based Cavalieri's Method

INTRODUCTION

Schizophrenia is a severe psychotic brain disorder. One of the potential mechanisms underlying this disease may be volumetric changes in some brain regions. The present study aimed to employ magnetic resonance imaging (MRI) to estimate and quantitatively analyze the brain of patients with schizophrenia compared to the controls.

METHODS

This case-control study was conducted on MRI scans of 20 patients with schizophrenia and 20 healthy controls in Zahedan City, Southeastern Iran. MRIs with 4 mm slice thickness and 5 mm intervals in coronal and sagittal planes were captured. Then, quantitative parameters, including volume and volume density of various brain regions, were estimated in both groups using Cavalieri's point counting method. Data analyses were performed using the Mann-Whitney U test.

RESULTS

The findings of this investigation revealed that volumes of gray matter, hippocampus, and gray/white matter in patients with schizophrenia were significantly lower than the controls (P<0.05). The volumes of lateral ventricles in patients with schizophrenia (36.60±4.32 mm3) were significantly higher than the healthy individuals (30.10±7.98 mm3). However, there were no statistically significant differences between the two groups regarding the changes in the brain's total volume, cerebral hemispheres, white matter, brain stem, cerebellum, and corpus callosum (P>0.05).

CONCLUSION

Volumetric estimations on brain MRI-based stereological technique can be helpful for elucidation of structural changes, following up the treatment trends, and evaluating the therapeutic situations in schizophrenia patients. Volumetric alternations in specific brain areas might be linked to cognitive impairments and the severity of symptoms in patients with schizophrenia. Further research is needed in this regard.

HIGHLIGHTS

Volumetric changes occur in certain regions of the brain of schizophrenia patients.Structural changes in the brain of schizophrenia patients are associated with the severity of clinical manifestations.A brain MRI-based stereological technique can clarify neuropathology and assess therapeutic efficiency in patients with schizophrenia.

PLAIN LANGUAGE SUMMARY

Schizophrenia is a severe neuropsychiatric disorder with worldwide prevalence that disrupts a person's social life. It's characterized by progressive neuroanatomical alterations in both gray and white matter in different brain regions and associated with changes in the structural and functioning of some critical brain circuits. Several factors have been suggested to be involved in the development and progression of the disease including alternations and disconnection in myelin, genetic factors, neurodegenerative process, neuroinflammation, neurodevelopmental deficiencies, the number of dopaminergic neurons and volumetric changes in different areas of the brain. It has shown that quantitative volumetric brain measurements on magnetic resonance imaging (MRI) scans in patients with neurodegenerative disease owing to selective regional atrophy are beneficial for clinicians to ascertain disease progression and to evaluate volume alternations and response to treatment. Thus, we investigated structural changes of the brain in schizophrenia patients on MR images using accurate Cavalieri's estimation and compared to healthy controls. The findings demonstrated that some structural changes occurs in various brain areas which involved in many critical roles in normal brain's functionality and connectivity. On the other hand, these changes are associated with cognitive impairments and the severity of clinical symptoms in patients with schizophrenia. It's appears that elucidation of the different pathways of various structural abnormalities related to schizophrenia is required to recognize and determine the role of discrete pathophysiological phenomena in mental illness development and progress.

Oxidative Stress Biomarkers among Schizophrenia Inpatients

Background. Finding the associations between schizophrenia symptoms and the biomarkers of inflammation, oxidative stress and the kynurenine pathway may lead to the individualization of treatment and increase its effectiveness. Methods. The study group included 82 schizophrenia inpatients. The Positive and Negative Symptoms Scale (PANSS), the Brief Assessment of Cognition in Schizophrenia (BACS) and the Calgary Depression in Schizophrenia Scale were used for symptom evaluation. Biochemical analyses included oxidative stress parameters and brain-derived neurotrophic factor (BDNF). Results. Linear models revealed the following: (1) malondiadehyde (MDA), N-formylkynurenine (N-formKYN), advanced oxidation protein products (AOPP), advanced glycation end-products of proteins (AGE) and total oxidative status (TOS) levels are related to the PANSS-total score; (2) MDA, reduced glutathione (GSH) and BDNF levels are related to the PANSS-negative score; (3) TOS and kynurenine (KYN) levels are related to the PANSS-positive score; (4) levels of total antioxidant status (TAS) and AOPP along with the CDSS score are related to the BACS-total score; (5) TAS and N-formKYN levels are related to the BACS-working memory score. Conclusions. Oxidative stress biomarkers may be associated with the severity of schizophrenia symptoms in positive, negative and cognitive dimensions. The identification of biochemical markers associated with the specific symptom clusters may increase the understanding of biochemical profiles in schizophrenia patients.

A comparison of dissolving microneedles and transdermal film with solid microneedles for iloperidone in vivo: a proof of concept

Iloperidone (ILO) is a poorly soluble and bioavailable WHO-approved schizophrenia drug. Microneedles are a revolutionary delivery technology that overcomes many of the issues associated with traditional drug administration. The current research aimed to compare the antipsychotic activity and pharmacokinetics of ILO-loaded dissolving microneedles (DMNs) and transdermal film with a solid microneedle (STF). The DMNs were fabricated using the micromolding process, while the transdermal film was created using the solvent casting approach. Furthermore, an in vivo pharmacokinetic, pharmacodynamic, and skin irritation study was performed on Wistar rats. Studies were compared with transdermal film (TF) on untreated skin as a passive control. STF and DMNs had considerably greater AUC and C_max (p ≤ 0.001) than transdermal film. In pharmacodynamic tests, STF and DMNs demonstrated significant (p ≤ 0.001) forelimb retraction time (FRT) and hindlimb retraction time (HRT) delay responses as compared to control and TF. In the skin irritation test, no adverse effects such as erythema or edema were observed at the end of the 48 h. Thus, antipsychotic activity (paw test) and pharmacokinetics studies revealed sustained action of DMN and STF. This research revealed that improved efficacy of DMN and STF for antipsychotic drug delivery may be an alternative to the existing dosage form.

Comparative Analysis of the Pre- and Post-Medication Effects of Antipsychotic Agents on the Blood-Based Oxidative Stress Biomarkers in Patients with Schizophrenia: A Meta-Analysis

OBJECTIVE

Studies have shown that oxidative stress (OS) is related to the pathophysiology of schizophrenia (SCZ), but whether antipsychotics can induce OS has not been investigated well. Moreover, antipsychotics have differential effects on the OS level modulation, i.e., different types of antipsychotics have different effects on the cellular antioxidants or pro-oxidants.

METHODS

We followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines and investigated the OS indicators including both enzymatic and nonenzymatic markers, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), malondialdehyde (MDA), glutathione (GSH), vitamin C, etc., of SCZ patients at baseline and follow-up of mono-medication.

RESULTS

Twenty studies met the inclusion criteria, with a total of 1162 patients enrolled at baseline, and 1105 patients completed the follow-up. OS markers were changed after a period of antipsychotic treatment in SCZ patients. The GPx activity and MDA level decreased in the whole blood (P<0.05), also the serum MDA level decreased (P<0.05). For the first-episode SCZ patients, the activity of GPx and the level of MDA decreased, while the level of vitamin C increased (all P<0.05). The levels of MDA in patients receiving atypical antipsychotics decreased (P<0.05), while the level of GSH in patients with typical antipsychotics decreased (P=0.05).

CONCLUSION

Antipsychotic medication may cause changes in the levels of OS markers in different blood samples of SCZ patients. However, the available studies might not be sufficient to reveal the underlying facts accurately due to the poor quality of experimental designs in the published literature.

It takes two to tango: Widening our understanding of the onset of schizophrenia from a neuro-angiogenic perspective

Schizophrenia is a chronic debilitating mental disorder characterized by perturbations in thinking, perception, and behavior, along with brain connectivity deficiencies, neurotransmitter dysfunctions, and loss of gray brain matter. To date, schizophrenia has no cure and pharmacological treatments are only partially efficacious, with about 30% of patients describing little to no improvement after treatment. As in most neurological disorders, the main descriptions of schizophrenia physiopathology have been focused on neural network deficiencies. However, to sustain proper neural activity in the brain, another, no less important network is operating: the vast, complex and fascinating vascular network. Increasing research has characterized schizophrenia as a systemic disease where vascular involvement is important. Several neuro-angiogenic pathway disturbances have been related to schizophrenia. Alterations, ranging from genetic polymorphisms, mRNA, and protein alterations to microRNA and abnormal metabolite processing, have been evaluated in plasma, post-mortem brain, animal models, and patient-derived induced pluripotent stem cell (hiPSC) models. During embryonic brain development, the coordinated formation of blood vessels parallels neuro/gliogenesis and results in the structuration of the neurovascular niche, which brings together physical and molecular signals from both systems conforming to the Blood-Brain barrier. In this review, we offer an upfront perspective on distinctive angiogenic and neurogenic signaling pathways that might be involved in the biological causality of schizophrenia. We analyze the role of pivotal angiogenic-related pathways such as Vascular Endothelial Growth Factor and HIF signaling related to hypoxia and oxidative stress events; classic developmental pathways such as the NOTCH pathway, metabolic pathways such as the mTOR/AKT cascade; emerging neuroinflammation, and neurodegenerative processes such as UPR, and also discuss non-canonic angiogenic/axonal guidance factor signaling. Considering that all of the mentioned above pathways converge at the Blood-Brain barrier, reported neurovascular alterations could have deleterious repercussions on overall brain functioning in schizophrenia.

Effects of antipsychotics on antioxidant defence system in patients with schizophrenia: A meta-analysis

Theory of oxidative stress is suggested in the pathophysiology of schizophrenia. To determine the cause of impaired antioxidant defense system in schizophrenia, a meta-analysis was performed by selecting studies published from 1964 to 2021 from Pubmed and Scopus databases. Data were analysed using Comprehensive Meta-Analysis version 2 and calculated effect sizes were compared between unmedicated and medicated patients with schizophrenia and healthy controls. Heterogeneity, publication bias assessments and subgroup analyses of drug-free and drug-naïve patients, and patients treated with atypical and typical antipsychotics were conducted. Subgroup analysis of confounding factors including age, gender, illness duration and patient status was also conducted. We found that glutathione peroxidase (GPx) was significantly decreased in all patients. Significantly lower catalase (CAT), glutathione (GSH) and albumin (ALB) were found in unmedicated patients only. Both groups showed significantly weakened non-enzymatic antioxidant capacity. Subgroup analyses indicated that weakened non-enzymatic antioxidant capacity may be associated with schizophrenia. Antioxidant status was more impaired in drug-free patients compared with other subgroups. This indicated that antipsychotics may improve antioxidant defense system. Although effect sizes were smaller, future studies may focus on the effect of antipsychotic discontinuation. In overall, schizophrenia was associated with impaired antioxidant defense system especially the non-enzymatic antioxidant system.

An Update on the Exploratory Use of Curcumin in Neuropsychiatric Disorders

Curcumin is a polyphenol extracted from the rhizome of the turmeric plant. Beyond its common use as a culinary spice in Eastern Asia, curcumin has been proposed as a therapeutic compound due to its antioxidant, anti-inflammatory and neuroprotective properties. Thus, its efficacy has been evaluated in various inflammatory-based psychiatric disorders, such as schizophrenia, depression, or autism. Our aim is to review those preclinical and clinical studies carried out in psychiatric disorders whose therapeutic approach has involved the use of curcumin and, therefore, to discern the possible positive effect of curcumin in these disorders. Preclinical studies and completed clinical trials of curcumin for psychiatric disorders published from January 2005 to October 2021 were identified through searching relevant databases until 31st October 2021. Sixty-five preclinical studies and 15 clinical trials and open-label studies were selected. Results showed a bias toward studies in depression and, to a lesser extent, schizophrenia. In all disorders, the results were positive in reducing psychiatric deficits. Despite the considerable number of beneficial outcomes reported, the small number of trials and the heterogeneity of protocols make it difficult to draw solid conclusions about the real potency of curcumin in psychiatric disorders.

Resveratrol prevents haloperidol-induced mitochondria dysfunction through the induction of autophagy in SH-SY5Y cells

BACKGROUND

Haloperidol is a commonly used antipsychotic drug and may increase neuronal oxidative stress associated with the side effects, including tardive dyskinesia and neurite withdraw. Autophagy plays a protective role in response to the accumulated reactive oxygen species (ROS) induced mitochondria damage. Resveratrol is an antioxidant compound having neuroprotective effects; however, it is unknown if resveratrol may stimulate autophagy and decrease mitochondria damage induced by haloperidol.

HYPOTHESIS

We hypothesis that resveratrol stimulates the autophagic process and protects mitochondria lesion induced by haloperidol.

METHODS

MitoSOX™ Red Mitochondrial Superoxide Indicator and MitoTracker™ Green FM staining were used to measure the amount of the mitochondria ROS production and mitochondria mass in human SH-SY5Y cells treated with haloperidol and/or resveratrol. Autophagic related dyes and Western blot were applied to study the autophagic process and related protein expression. Besides, tandem monomeric mRFP-GFP-LC3 was used to investigate the fusion of autophagosome and lysosome. Transmission electron microscopy was used to investigate the mitochondrial and autophagic ultrastructures with or without haloperidol and resveratrol treatment.

RESULTS

Haloperidol administration significantly increased mitochondria ROS and mitochondrial mass, indicating the increase of mitochondria dysfunction. Although haloperidol increased the autophagosomes and lysosome formation, the autophagosome-lysosome fusion and degradation were impaired. This was because we found an increased p62 after haloperidol treatment, an indication of autophagy incompletion. Importantly, resveratrol promoted the degradation of p62, upregulated the formation of autophagolysosome, and reversed haloperidol-induced mitochondria damage.

CONCLUSION

These results collectively suggest that resveratrol may be introduced as a protective compound against haloperidol-induced mitochondria impairment and aberrant autophagy.

Haloperidol elicits oxidative damage in the brain of rats submitted to the ketamine-induced model of schizophrenia

The present study aims to evaluate the effects of haloperidol, an important first-generation antipsychotic, on the antioxidant system parameters in the brain of animals subjected to a model of schizophrenia induced by ketamine. Adult rats intraperitoneally received saline (1 mL/kg) or ketamine (25 mg/kg body weight) for 15 days, and saline or haloperidol (0.1 mg/kg body weight) via gavage once a day, between the 9th and 14th days. In the frontal cortex, hippocampus, and striatum, assessments of lipid (4-hydroxy-2-nonenal and 8-isoprostane levels) and protein (protein carbonyl content) oxidative damage were conducted. It was also measured the glutathione peroxidase and glutathione reductase activities in the same cerebral structures. Increases in the 4-hydroxy-2-nonenal and 8-isoprostane levels were detected in rats receiving haloperidol and ketamine. An increase in the carbonyl content was also observed in animals receiving ketamine, haloperidol, or a combination thereof. In animals receiving the antipsychotic, there was a decrease in the activity of the enzymes. Therefore, both ketamine and haloperidol induced oxidative damage. A possible energy dysfunction or a haloperidol effect targeting the glutathione enzymes, and then disrupting the redox homeostasis in neurons, could not be ruled out, although further studies are required to confirm or refute a direct interaction.

Altered Antioxidant Defenses in Drug-Naive First Episode Patients with Schizophrenia Are Associated with Poor Treatment Response to Risperidone: 12-Week Results from a Prospective Longitudinal Study

Abnormal redox regulation is thought to contribute to schizophrenia (SCZ). Accumulating studies have shown that the plasma antioxidant enzyme activity is closely associated with the course and outcome in antipsychotics-naïve first-episode (ANFE) patients with SCZ. The main purpose of this study was to investigate the effect of risperidone on oxidative stress markers in ANFE patients and the relationship between risperidone response and changes in oxidative stress markers. Plasma activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) enzyme, total antioxidant status (TAS), and malondialdehyde (MDA) levels were measured in 354 ANFE patients and 152 healthy controls. The clinical symptoms were evaluated by the Positive and Negative Syndrome Scale (PANSS). Patients received risperidone monotherapy for 12 weeks and oxidative stress markers and PANSS were measured at baseline and at follow-up. Compared with healthy controls, the patients exhibited higher activities of SOD, CAT, and TAS levels, but lower MDA levels and GPx activity. A comparison between 168 responders and 50 non-responders at baseline and 12-week follow-up showed that GPx activity decreased in both groups after treatment. Moreover, GPx activity decreased less in responders and was higher in responders than in non-responders at follow-up. These results demonstrate that the redox regulatory system and antioxidant defense enzymes may have predictive value for the response of ANFE patients to risperidone treatment.

Effects of several atypical antipsychotics closapine, sertindole or ziprasidone on hepatic antioxidant enzymes: Possible role in drug-induced liver dysfunction

Chronic use of atypical antipsychotics may produce hepatic damage. Atypical antipsychotics, including clozapine, sertindole, and ziprasidone, are extensively metabolized by the liver and this process generates toxic-free radical metabolic intermediates which may contribute to liver damage. The aim of this study was to investigate whether clozapine, sertindole, or ziprasidone affected hepatic antioxidant defense enzymes which consequently led to disturbed redox homeostasis. The expression and activity of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), and glutathione-S-transferases (GST) were measured in rat livers at doses corresponding to human antipsychotic therapy. Clozapine increased activity of SOD types 1 and 2, GR and GST, but reduced CAT activity. Sertindole elevated activities of both SODs. In ziprasidone-treated rats only decreased CAT activity was found. All three antipsychotics produced mild-to-moderate hepatic histopathological changes categorized as regenerative alterations. No apparent signs of immune cell infiltration, microvesicular or macrovesicular fatty change, or hepatocytes in mitosis were observed. In conclusion, a 4-week long daily treatment with clozapine, sertindole, or ziprasidone altered hepatic antioxidant enzyme activities and induced histopathological changes in liver. The most severe alterations were noted in clozapine-treated rats. Data indicate that redox disturbances may contribute to liver dysfunction after long-term atypical antipsychotic drug treatment.

Oxidative Stress-Related Mechanisms in Schizophrenia Pathogenesis and New Treatment Perspectives

Schizophrenia is recognized to be a highly heterogeneous disease at various levels, from genetics to clinical manifestations and treatment sensitivity. This heterogeneity is also reflected in the variety of oxidative stress-related mechanisms contributing to the phenotypic realization and manifestation of schizophrenia. At the molecular level, these mechanisms are supposed to include genetic causes that increase the susceptibility of individuals to oxidative stress and lead to gene expression dysregulation caused by abnormal regulation of redox-sensitive transcriptional factors, noncoding RNAs, and epigenetic mechanisms favored by environmental insults. These changes form the basis of the prooxidant state and lead to altered redox signaling related to glutathione deficiency and impaired expression and function of redox-sensitive transcriptional factors (Nrf2, NF-κB, FoxO, etc.). At the cellular level, these changes lead to mitochondrial dysfunction and metabolic abnormalities that contribute to aberrant neuronal development, abnormal myelination, neurotransmitter anomalies, and dysfunction of parvalbumin-positive interneurons. Immune dysfunction also contributes to redox imbalance. At the whole-organism level, all these mechanisms ultimately contribute to the manifestation and development of schizophrenia. In this review, we consider oxidative stress-related mechanisms and new treatment perspectives associated with the correction of redox imbalance in schizophrenia. We suggest that not only antioxidants but also redox-regulated transcription factor-targeting drugs (including Nrf2 and FoxO activators or NF-κB inhibitors) have great promise in schizophrenia. But it is necessary to develop the stratification criteria of schizophrenia patients based on oxidative stress-related markers for the administration of redox-correcting treatment.

Comparative Study of the Effects of Atypical Antipsychotic Drugs on Plasma and Urine Biomarkers of Oxidative Stress in Schizophrenic Patients

PURPOSE

Evidence that antipsychotic drugs (ADs) can affect oxidative stress estimated with various biomarkers in schizophrenic patients is controversial and limited. Therefore, in the present study, we assessed the ability of six atypical ADs (clozapine, olanzapine, quetiapine, risperidone, aripiprazole, and ziprasidone) used in schizophrenia treatment to modulate oxidative damage to different biomolecules such as lipids and proteins.

PATIENTS AND METHODS

We measured the levels of oxidative stress markers in plasma and urine: total antioxidant capacity by FRAP (according to a modified method of Benzie & Strain), thiobarbituric acid reactive species - TBARS (spectrophotometric method), 4-hydroxy-2-nonenal (4-HNE) (OxiSelect™ HNE Adduct Competitive ELISA Kit), 3-nitrotyrosine (3-NT) (OxiSelect™ Nitrotyrosine ELISA Kit) in plasma, and F2-isoprostanes (BIOXYTECH^® Urinary 8-epi-Prostaglandin F2α) in the urine of 60 schizophrenic patients (before and after treatment) and in 30 healthy subjects.

RESULTS

Our results showed that in schizophrenic patients levels of lipid peroxidation markers (TBARS, F2-isoprostanes) were higher than in healthy subjects but FRAP in schizophrenic patients was lower than in healthy controls and increased after 4-week treatment with tested ADs. A 4-week treatment with ADs caused the improvement of psychopathology symptoms estimated by Positive and Negative Syndrome Scale (PANSS) that was accompanied by decreased lipid peroxidation (F2-isoprostanes, TBARS; p=2.9x10^-6, p=7.6x10^-5, respectively) and an increase in total antioxidative capacity (FRAP) (p=5.16x10^-16).

CONCLUSION

Atypical antipsychotics especially clozapine, olanzapine and quetiapine demonstrate the effective outcome of antipsychotic treatment, beneficial antioxidative action by reducing lipid peroxidation and increased total plasma antioxidant activity.

Antioxidant Properties of Second-Generation Antipsychotics: Focus on Microglia

Recent studies suggest a primary role of oxidative stress in an early phase of the pathogenesis of schizophrenia and a strong neurobiological link has been found between dopaminergic system dysfunction, microglia overactivation, and oxidative stress. Different risk factors for schizophrenia increase oxidative stress phenomena raising the risk of developing psychosis. Oxidative stress induced by first-generation antipsychotics such as haloperidol significantly contributes to the development of extrapyramidal side effects. Haloperidol also exerts neurotoxic effects by decreasing antioxidant enzyme levels then worsening pro-oxidant events. Opposite to haloperidol, second-generation antipsychotics (or atypical antipsychotics) such as risperidone, clozapine, and olanzapine exert a strong antioxidant activity in experimental models of schizophrenia by rescuing the antioxidant system, with an increase in superoxide dismutase and glutathione (GSH) serum levels. Second-generation antipsychotics also improve the antioxidant status and reduce lipid peroxidation in schizophrenic patients. Interestingly, second-generation antipsychotics, such as risperidone, paliperidone, and in particular clozapine, reduce oxidative stress induced by microglia overactivation, decreasing the production of microglia-derived free radicals, finally protecting neurons against microglia-induced oxidative stress. Further, long-term clinical studies are needed to better understand the link between oxidative stress and the clinical response to antipsychotic drugs and the therapeutic potential of antioxidants to increase the response to antipsychotics.

Investigation of the effects of cannabidiol on vacuous chewing movements, locomotion, oxidative stress and blood glucose in rats treated with oral haloperidol

Objectives: Tardive dyskinesia (TD) unlike acute dystonia may be irreversible. This study investigated the effects of oral cannabidiol (CBD) on haloperidol-induced vacuous chewing movement (VCM) model of TD. Methods: There were six experimental groups with different combinations of oral cannabidiol with 5 mg/kg of haloperidol given orally. Behavioural assays and FBS were measured. VCMs were assessed after the last dose of medication. Blood for oxidative stress assays was collected on the 8th day after the administration of the last dose of medication. Results: This study found that CBD co-administration with haloperidol attenuated the VCMs and increased motor tone produced by haloperidol. CBD alone at 5 mg/kg appears to have anxiolytic properties but may not be as effective as haloperidol which exhibited a greater anxiolytic effect at 5 mg/kg. Treatment with CBD alone at 5 mg/kg also appeared to enhance brain DPPH scavenging activity. Conclusions: We confirmed that CBD can ameliorate motor impairments produced by haloperidol. Our data suggest that CBD can be combined with haloperidol to prevent the emergent of extrapyramidal side effects and long-term movement disorders, such as acute dystonic disorder and TD.

Antioxidant properties of the Lebanese plant Iris x germanica L. crude extracts and antagonism of chlorpromazine toxicity on Saccharomyces cerevisiae

Iris x germanica L., which belongs to the Iridaceae family, has been reported in the literature for its antioxidant properties in acellular chemical-antioxidant assays. Chlorpromazine (CPZ) is an antipsychotic drug known to cause adverse reactions in humans. Oxidative stress is among the main mechanisms by which CPZ exerts its toxicity in animal cell models as well as in the yeast Saccharomyces cerevisiae. In this study we investigated the protective effects of I. germanica L. crude extracts against CPZ toxicity. We demonstrated that methanolic extracts from rhizome (R-M), leaf (L-M) and flower (Fl-M) had potent antioxidant activity by scavenging the free radical DPPH, with half-maximal effective concentrations (EC₅₀) 193, 107, and 174 µg/mL, respectively. R-M, L-M and Fl-M at doses up to 1000 µg/mL, didn't affect yeast cell growth. In addition, we demonstrated for the first time that L-M at 1000 µg/mL and R-M at all tested doses counteracted CPZ toxicity, probably by promoting yeast cell antioxidant agents. The R-M capacity to counteract CPZ toxicity was lost in the yeast strain mutant in catalase-encoding gene (Cta1), while strains mutant in Sod2, Skn7 and Rap1 showed mild or full R-M-induced protective effect against CPZ toxicity. Our results demonstrated that I. germanica L. R-M extract counteracted CPZ toxicity in the yeast cell model. Further studies are planned to isolate the involved bioactive compounds and identify the involved genes and the antioxidant agents.

Ubiquitin-proteasome system, lipid metabolism and DNA damage repair are triggered by antipsychotic medication in human oligodendrocytes: implications in schizophrenia

Schizophrenia is a chronic, severe and disabling psychiatric disorder, whose treatment is based on psychosocial interventions and the use of antipsychotic drugs. While the effects of these drugs are well elucidated in neuronal cells, they are still not so clear in oligodendrocytes, which play a vital role in schizophrenia. Thus, we aimed to characterize biochemical profiles by proteomic analyses of human oligodendrocytes (MO3.13) which were matured using a protocol we developed and treated with either haloperidol (a typical antipsychotic), clozapine (an atypical antipsychotic) or a clozapine + D-serine co-treatment, which has emerged lately as an alternative type of treatment. This was accomplished by employing shotgun proteomics, using nanoESI-LC-MS/MS label-free quantitation. Proteomic analysis revealed biochemical pathways commonly affected by all tested antipsychotics were mainly associated to ubiquitination, proteasome degradation, lipid metabolism and DNA damage repair. Clozapine and haloperidol treatments also affected proteins involved with the actin cytoskeleton and with EIF2 signaling. In turn, metabolic processes, especially the metabolism of nitrogenous compounds, were a predominant target of modulation of clozapine + D-serine treatment. In this context, we seek to contribute to the understanding of the biochemical and molecular mechanisms involved in the action of antipsychotics on oligodendrocytes, along with their possible implications in schizophrenia.

Ameliorative effect of Nigella sativa oil and vitamin C on the thyroid gland and cerebellum of adult male albino rats exposed to Monosodium glutamate (histological, immunohistochemical and biochemical studies)

Monosodium glutamate (MSG) is a major taste enhancer that is used as a food additive. Vitamin C (Vit C) and Nigella sativa oil (NSO) are known for their potent antioxidant activities.

OBJECTIVE

This study investigates the adverse effect of MSG on the thyroid gland and cerebellum of adult male albino rats and the protection against MSG-mediated toxicity provided by Vit C and NSO.

DESIGN

Fifty rats were divided into five groups that were treated via oral gavage. Group I (control) rats received distilled water, Group II rats were treated with MSG (6 mg/gm body weight/day), Group III rats were treated with MSG and Vit C (100 mg/kg body weight /day), Group IV rats were treated with MSG and NSO (50 mg/kg body weight two times per week), and Group V rats were treated with MSG together with both Vit C and NSO with MSG. After 60 days of treatment, rats were euthanized and histological sections were prepared from the thyroid gland and the cerebellum for routine staining and immunohistochemical detection of glial fibrillar acidic protein (GFAP), Caspase-3 and proliferating cell nuclear antigen (PCNA), respectively. Cerebellar tissue was also evaluated to determine glutathione (GSH) and malondialdehyde (MDA) levels; GSH was also measured in thyroid tissue. Serum levels of fT3, fT4 and TSH (thyroid stimulating hormone) were also evaluated.

RESULTS

Microscopic examination of cerebellar tissues revealed significant cerebellar injury and cellular apoptosis among the rats in Group II. The thyroid glands of Group II rats were notable for degenerating follicles, loss of colloid, sloughed follicular cells and congested blood vessels. The cerebellar and thyroid tissues from rats in treatment Groups III, IV and V revealed significantly less pathology. Cerebellar and thyroid tissues from Group II rats that were treated with MSG alone revealed intense GFAP and caspase-3 (cerebellar) and PCNA (thyroid) immunoreactivity. Furthermore, cerebellar tissues from rats received MSG alone (Group II) were notable for decreased levels of GSH and increased levels of MDA; thyroid tissue from rats in Group II also demonstrated decreased levels of GSH. Likewise, serum fT3 and fT4 levels were significantly decreased, while serum TSH was significantly increased among rats in Group II. Combined administration of Vit C and NSO together with MSG (Group V) revealed some variations in oxidative parameters compared to those in the Group I control rats.

CONCLUSIONS

Oral intake of MSG resulted in degenerative changes in neurons and astrocytes in cerebellum and, also degeneration of the thyroid glands of albino rats. Concomitant administration of Vit C and NSO may limit MSG-induced damage to the cerebellum and thyroid glands and thereby provide significant protection against the oxidative damage induced by MSG.

Interaction of cigarette smoke condensate and some of its components with chlorpromazine toxicity on Saccharomyces cerevisiae

Chlorpromazine (CPZ) is an antipsychotic phenothiazine which is still commonly prescribed though it causes idiosyncratic toxicity such as cholestasis. CPZ toxicity mechanisms involve oxidative stress among others. Cigarette smoke (CS) causes deleterious effects through diverse mechanisms such as oxidative stress. CS alters drug metabolizing enzymes expression and drug transporters expression and activity in animal cell models as well as in Saccharomyces cerevisiae. CS therefore alters pharmacokinetic and pharmacodynamics of many drugs including CPZ and caffeine whose toxicity is promoted by CS condensate (CSC). CSC interaction with CPZ toxicity deserves investigation. In this study, CSC exerted mild toxicity on Saccharomyces cerevisiae which resisted to this chemical stress after several hours. CPZ toxicity on yeast was dose-dependent and the cells resisted to CPZ up to 40 µM after 24 h of treatment. Yeast cells treated simultaneously with CPZ and a nontoxic CSC dose were less sensitive to CPZ. CSC probably triggers cross-resistance to CPZ. Using Sod1 mutant strain, we showed that this gene is potentially involved in the potential cross-resistance. Other genes encoding stress-related transcription factors could be involved in this process. Nicotine and cadmium chloride, which caused a dose-dependent toxicity individually, acted with CPZ in an additive or synergistic manner in terms of toxicity. Although our results cannot be extrapolated to humans, they clearly show that CSC and its components interact with CPZ toxicity.

Galantamine-Memantine Combination as an Antioxidant Treatment for Schizophrenia

PURPOSE OF REVIEW

The objective of this article is to highlight the potential role of the galantamine-memantine combination as a novel antioxidant treatment for schizophrenia.

RECENT FINDINGS

In addition to the well-known mechanisms of action of galantamine and memantine, these medications also have antioxidant activity. Furthermore, an interplay exists between oxidative stress, inflammation (redox-inflammatory hypothesis), and kynurenine pathway metabolites. Also, there is an interaction between brain-derived neurotrophic factor and oxidative stress in schizophrenia. Oxidative stress may be associated with positive, cognitive, and negative symptoms and impairments in white matter integrity in schizophrenia. The antipsychotic-galantamine-memantine combination may provide a novel strategy in schizophrenia to treat positive, cognitive, and negative symptoms.

SUMMARY

A "single antioxidant" may be inadequate to counteract the complex cascade of oxidative stress. The galantamine-memantine combination as "double antioxidants" is promising. Hence, randomized controlled trials are warranted with the antipsychotic-galantamine-memantine combination with oxidative stress and antioxidant biomarkers in schizophrenia.

Chronic Antipsychotic Treatment Modulates Aromatase (CYP19A1) Expression in the Male Rat Brain

Antipsychotic drugs, known as the antagonists of dopaminergic receptors, may also affect a large spectrum of other molecular signaling pathways in the brain. Despite the numerous ongoing studies on neurosteroid action and regulation, there are no reports regarding the influence of extended treatment with typical and atypical neuroleptics on brain aromatase (CYP19A1) expression. In the present study, we assessed for the first time aromatase mRNA and protein levels in the brain of rats chronically (28 days) treated with olanzapine, clozapine, and haloperidol using quantitative real-time PCR, end-point RT-PCR, and Western blotting. Both clozapine and haloperidol, but not olanzapine treatment, led to an increase of aromatase mRNA expression in the rat brain. On the other hand, aromatase protein level remained unchanged after drug administration. These results cast a new light on the pharmacology of examined antipsychotics and contribute to a better understanding of the mechanisms responsible for their action. The present report also underlines the complex nature of potential interactions between neuroleptic pharmacological effects and physiology of brain neurosteroid pathways.

Intermittent Administration of Haloperidol after Cortical Impact Injury Neither Impedes Spontaneous Recovery Nor Attenuates the Efficacy of Environmental Enrichment

The administration of haloperidol (HAL) once-daily for 19 days after experimental traumatic brain injury (TBI) impedes recovery and attenuates the efficacy of environmental enrichment (EE). However, it is unknown how intermittent administration of HAL affects the recovery process when paired with EE. Addressing the uncertainty is relevant because daily HAL is not always warranted to manage TBI-induced agitation in the clinic, and indeed intermittent therapy may be a more common approach. Hence, the aim of the study was to test the hypothesis that intermittent HAL would neither impair recovery in standard (STD)-housed controls nor attenuate the efficacy of EE. Anesthetized adult male rats received a cortical impact or sham injury and then were housed in STD or EE conditions. Beginning 24 h later, HAL (0.5 mg/kg; intraperitoneally [i.p.]) was administered either once-daily for 19 days or once every other day, whereas vehicle (VEH; 1 mL/kg; i.p.) was administered once daily. Motor performance and cognition were assessed on post-injury days 1-5 and 14-19, respectively. Cortical lesion volume was quantified on day 21. SHAM controls performed better than all TBI groups on motor and spatial learning [p < 0.05], but did not differ from the TBI + EE + daily VEH group on memory retention [p > 0.05]. The TBI + EE + daily VEH and TBI + EE + intermittent HAL groups did not differ from one another on beam-walk or spatial learning [p > 0.05], and both performed better than all other TBI groups [p < 0.05]. In contrast, the TBI + STD + daily HAL group performed worse than all TBI groups on spatial learning [p < 0.05]. No difference in any endpoint was revealed between the TBI + STD + intermittent HAL and TBI + STD + daily VEH groups [p > 0.05]. The results support the hypothesis that HAL is not detrimental when provided intermittently. If translatable to the clinic, intermittent HAL may be used to control TBI-induced agitation without negatively affecting spontaneous recovery or rehabilitative efficacy.

Atypical antipsychotics-induced metabolic syndrome and nonalcoholic fatty liver disease: a critical review

The atypical antipsychotics (AAPs) have been used as first-line drugs in psychiatric practice for a wide range of psychotic disorders, including schizophrenia and bipolar mania. While effectively exerting therapeutic effects on positive and negative symptoms, as well as cognitive impairments in schizophrenia patients, these drugs are less likely to induce extrapyramidal symptoms compared to typical antipsychotics. However, the increasing application of them has raised questions on their tolerability and adverse effects over the endocrine, metabolic, and cardiovascular axes. Specifically, AAPs are associated to different extents, with weight gain, metabolic syndrome (MetS), and nonalcoholic fatty liver disease (NAFLD). This article summarized clinical evidence showing the metabolic side effects of AAPs in patients with schizophrenia, and experimental evidence of AAPs-induced metabolic side effects observed in animals and cell culture studies. In addition, it discussed potential mechanisms involved in the APPs-induced MetS and NAFLD.

Comparative effects of aripiprazole and selected antipsychotic drugs on lipid peroxidation in plasma

AIM

The aim of the present study was to evaluate and compare the effects of a new antipsychotic, aripiprazole (unique due to its mechanism of action), with the effects of selected antipsychotic drugs, such as quetiapine, olanzapine, clozapine, risperidone, and ziprasidone (at the final concentrations corresponding to clinically effective doses used for the treatment of acute episodes of schizophrenia) on lipid peroxidation in human plasma measured by the level of thiobarbituric acid reactive substances (TBARS), which is a marker of oxidative stress.

METHODS

The levels of TBARS were measured spectrophotometrically, according to the modification of the Rice-Evans method.

RESULTS

Our results indicate that antipsychotics at doses recommended for the treatment of acute episodes of schizophrenia may induce distinct changes in the levels of lipid peroxidation products (TBARS) in plasma. Aripiprazole had no effect on the level of a lipid peroxidation marker in plasma, although used at lower doses it showed insignificant prooxidative properties similar to clozapine. Quetiapine had the strongest antioxidant properties, contrary to prooxidative action of risperidone, ziprasidone or haloperidol, and clozapine at lower doses. Olanzapine reduced the level of TBARS in plasma only at a lower dose.

CONCLUSION

Antipsychotics at doses recommended for the treatment of acute episode in schizophrenia may induce the distinct changes in plasma lipid peroxidation. Aripiprazole did not induce significant changes in plasma lipid peroxidation. In further studies, the role of oxidative stress in schizophrenic patients together with their clinical symptomatology and use of antipsychotics should be taken into account.

Thiol Disulfide Homeostasis in Schizophrenic Patients Using Atypical Antipsychotic Drugs

Objective

Schizophrenia is a severe, debilitating mental disorder characterized by behavioral abnormalities. Although several studies have investigated the role of oxidative stress and the effects of antipsychotic drugs on oxidative markers in schizophrenia, adequate information is not available on these issues. The aim of this study is to determine the changes in oxidative status and thiol disulfide homeostasis in schizophrenic patients using atypical antipsychotic drugs.

Methods

Thirteen schizophrenic patients using atypical antipsychotic drugs and 30 healthy controls were included this study. The concentrations of total oxidant status (TOS), total antioxidant status (TAS), native thiol, total thiol, and disulfide levels were determined in the study population.

Results

The TAS (p=0.001), total thiol, and native thiol levels (p<0.001) were higher in the patients compared to the controls, whereas the TOS and disulfide levels were lower in the patients than in the controls (p<0.001).

Conclusion

These results may suggest that atypical antipsychotic drugs have a useful therapeutic effect by reducing oxidative stress via the inhibition of the formation of disulfide bonds. The study population number was one of the limitations of this study. Therefore, further studies are needed to establish the association between thiol disulfide homeostasis in schizophrenic patients using atypical antipsychotic drugs.

Serum agouti-related protein (AgRP) levels in bipolar disorder: Could AgRP be a state marker for mania?

Orexigenic and anorexigenic peptides, especially agouti-related protein (AgRP) and leptin, play important roles in the regulation of energy homeostasis in bipolar disorder. AgRP regulates energy metabolism by increasing appetite and decreasing energy expenditure. The resting energy expenditures of patients with manic bipolar disorder are higher than those of controls. Due to the effects of AgRP on energy expenditure and the increased physical activity of manic patients, we hypothesised that serum AgRP levels may be lower in manic patients than in euthymic patients and controls. There was a total of 112 participants, including 47 patients in the manic group, 35 patients in the euthymic group and 30 healthy controls. For this study, serum AgRP, leptin, cholesterol, and cortisol levels were measured and compared between the groups. The serum AgRP, leptin, and cholesterol levels were significantly different between the groups. The serum AgRP levels of manic group were significantly lower than those of euthymic and control groups. The lower serum AgRP levels of manic patients could be indicators of impaired energy homeostasis during manic episodes. Since the serum AgRP levels of manic patients are lower than those of euthymic patients and controls, AgRP could be a state marker for manic episodes.

Advantages of the Alpha-lipoic Acid Association with Chlorpromazine in a Model of Schizophrenia Induced by Ketamine in Rats: Behavioral and Oxidative Stress evidences

Schizophrenia is a chronic mental disorder reported to compromise about 1% of the world's population. Although its pathophysiological process is not completely elucidated, evidence showing the presence of an oxidative imbalance has been increasingly highlighted in the literature. Thus, the use of antioxidant substances may be of importance for schizophrenia treatment. The objective of this study was to evaluate the behavioral and oxidative alterations by the combination of chlorpromazine (CP) and alpha-lipoic acid (ALA), a potent antioxidant, in the ketamine (KET) model of schizophrenia in rats. Male Wistar rats (200-300 g) were treated for 10 days with saline, CP or ALA alone or in combination with CP previous to KET and the behavioral (open field, Y-maze and PPI tests) and oxidative tests were performed on the last day of treatment. The results showed that KET induced hyperlocomotion, impaired working memory and decreased PPI. CP alone or in combination with ALA prevented KET-induced behavioral effects. In addition, the administration of KET decreased GSH and increased nitrite, lipid peroxidation and myeloperoxidase activity. CP alone or combined with ALA prevented the oxidative alterations induced by KET. In conclusion, the treatment with KET in rats induced behavioral impairments accompanied by hippocampal oxidative alterations, possibly related to NMDA receptors hypofunction. Besides that, CP alone or combined with ALA prevented these effects, showing a beneficial activity as antipsychotic agents.

Linking lipid peroxidation and neuropsychiatric disorders: focus on 4-hydroxy-2-nonenal

4-hydroxy-2-nonenal (HNE) is considered to be a strong marker of oxidative stress; the interaction between HNE and cellular proteins leads to the formation of HNE-protein adducts able to alter cellular homeostasis and cause the development of a pathological state. By virtue of its high lipid concentration, oxygen utilization, and the presence of metal ions participating to redox reactions, the brain is highly susceptible to the formation of free radicals and HNE-related compounds. A variety of neuropsychiatric disorders have been associated with elevations of HNE concentration. For example, increased levels of HNE were found in the cortex of bipolar and schizophrenic patients, while HNE plasma concentrations resulted high in patients with major depression. On the same line, high brain concentrations of HNE were found associated with Huntington's inclusions. The incidence of high HNE levels is relevant also in the brain and cerebrospinal fluid of patients suffering from Parkinson's disease. Intriguingly, in this case the increase of HNE was associated with an accumulation of iron in the substantia nigra, a brain region highly affected by the pathology. In the present review we recapitulate the findings supporting the role of HNE in the pathogenesis of different neuropsychiatric disorders to highlight the pathogenic mechanisms ascribed to HNE accumulation. The aim of this review is to offer novel perspectives both for the understanding of etiopathogenetic mechanisms that remain still unclear and for the identification of new useful biological markers. We conclude suggesting that targeting HNE-driven cellular processes may represent a new more efficacious therapeutical intervention.

Level of serum thioredoxin and correlation with neurocognitive functions in patients with schizophrenia using clozapine and other atypical antipsychotics

Thioredoxin is a serum antioxidant that has been investigated in the etiology of schizophrenia. The aim of this study is investigating the relationship between serum thioredoxin levels and cognitive functions in acute psychotic episode and remission state patients with schizophrenia; and examining whether there were differences between patients using clozapine and other atypical antipsychotics; including risperidone, olanzapine and amisulpride. This research was performed in schizophrenia patients hospitalized with acute psychotic episode (n=57), reevaluated patients after the initiation of treatment (mean 16 weeks) (n=46), and healthy controls (n=41). Positive and Negative Syndrome Scale, Clinic Global Impressions Scale, Neuropsychologic test battery to assess cognitive performance, and serum thioredoxin levels measured by ELISA were used in this research. Serum thioredoxin levels were highest in acute psychotic episode, lower in the remission state and the lowest in healthy controls. Significant correlation has been established between serum thioredoxin levels and Trail Making Test-A performance in remission state patients. In conclusion, serum thioredoxin levels were increased in acute psychotic episode and decreased in remission state, and its relationship with attention is worth to consider in schizophrenia patients.

Cortical grey matter volume reduction in people with schizophrenia is associated with neuro-inflammation

Cortical grey matter volume deficits and neuro-inflammation exist in patients with schizophrenia, although it is not clear whether elevated cytokines contribute to the cortical volume reduction. We quantified cortical and regional brain volumes in fixed postmortem brains from people with schizophrenia and matched controls using stereology. Interleukin (IL)-6, IL-1β, IL-8 and SERPINA3 messenger RNAs (mRNAs) were quantified in the contralateral fresh frozen orbitofrontal cortex. We found a small, but significant reduction in cortical grey matter (1.3%; F(1,85)=4.478, P=0.037) and superior frontal gyrus (6.5%; F(1,80)=5.700, P=0.019) volumes in individuals with schizophrenia compared with controls. Significantly reduced cortical grey matter (9.2%; F(1,24)=8.272, P=0.008) and superior frontal gyrus (13.9%; F(1,20)=5.374, P=0.031) volumes were found in cases with schizophrenia and 'high inflammation' status relative to schizophrenia cases with 'low inflammation' status in the prefrontal cortex. The expression of inflammatory mRNAs in the orbitofrontal cortex was significantly correlated with those in dorsolateral prefrontal cortex (all r>0.417, all P<0.022), except for IL-8. Moreover, average daily and lifetime antipsychotic intake negatively correlated with cortical grey matter and superior frontal gyrus volumes (all r<-0.362, all P<0.05). The results suggest that the reduction in cortical grey matter volume in people with schizophrenia is exaggerated in those who have high expression of inflammatory cytokines. Further, antipsychotic medication intake does not appear to ameliorate the reduction in brain volume.

Switching antipsychotics: Imaging the differential effect on the topography of postsynaptic density transcripts in antipsychotic-naïve vs. antipsychotic-exposed rats

The postsynaptic density (PSD) has been regarded as a functional switchboard at the crossroads of a dopamine-glutamate interaction, and it is putatively involved in the pathophysiology of psychosis. Indeed, it has been demonstrated that antipsychotics may modulate several PSD transcripts, such as PSD-95, Shank, and Homer. Despite switching antipsychotics is a frequent strategy to counteract lack of efficacy and/or side effect onset in clinical practice, no information is available on the effects of sequential treatments with different antipsychotics on PSD molecules. The aim of this study was to evaluate whether a previous exposure to a typical antipsychotic and a switch to an atypical one may affect the expression of PSD transcripts, in order to evaluate potential neurobiological correlates of this common clinical practice, with specific regards to putative synaptic plasticity processes. We treated male Sprague-Dawley rats intraperitoneally for 15days with haloperidol or vehicle, then from the sixteenth day we switched the animals to amisulpride or continued to treat them with vehicle or haloperidol for 15 additional days. In this way we got six first treatment/second treatment groups: vehicle/vehicle, vehicle/haloperidol, vehicle/amisulpride, haloperidol/vehicle, haloperidol/haloperidol, haloperidol/amisulpride. In this paradigm, we evaluated the expression of brain transcripts belonging to relevant and interacting PSD proteins, both of the Immediate-Early Gene (Homer1a, Arc) and the constitutive classes (Homer1b/c and PSD-95). The major finding was the differential effect of amisulpride on gene transcripts when administered in naïve vs. antipsychotic-pretreated rats, with modifications of the ratio between Homer1a/Homer1b transcripts and differential effects in cortex and striatum. These results suggest that the neurobiological effects on PSD transcripts of amisulpride, and possibly of other antipsychotics, may be greatly affected by prior antipsychotic treatments and may impact significantly on the switching procedure.

Implications for reactive oxygen species in schizophrenia pathogenesis

Oxidative stress is a well-recognized participant in the pathophysiology of multiple brain disorders, particularly neurodegenerative conditions such as Alzheimer's and Parkinson's diseases. While not a dementia, a wide body of evidence has also been accumulating for aberrant reactive oxygen species and inflammation in schizophrenia. Here we highlight roles for oxidative stress as a common mechanism by which varied genetic and epidemiologic risk factors impact upon neurodevelopmental processes that underlie the schizophrenia syndrome. While there is longstanding evidence that schizophrenia may not have a single causative lesion, a common pathway involving oxidative stress opens the possibility for intervention at susceptible phases.

Effects of agmatine on chlorpromazine toxicity in the liver of Wistar rats: the possible role of oxidant/antioxidant imbalance

Chlorpromazine (CPZ) is a member of a widely used class of antipsychotic agents. The metabolic pathways of CPZ toxicity were examined by monitoring oxidative/nitrosative stress markers. The aim of the study was to investigate the hypothesis that agmatine (AGM) prevents oxidative stress in the liver of Wistar rats 48 h after administration of CPZ. All tested compounds were administered intraperitoneally (i.p.) in one single dose. The animals were divided into control (C, 0.9% saline solution), CPZ (CPZ, 38.7 mg/kg b.w.), CPZ+AGM (AGM, 75 mg/kg b.w. immediately after CPZ, 38.7 mg/kg b.w. i.p.), and AGM (AGM, 75 mg/kg b.w.) groups. Rats were sacrificed by decapitation 48 h after treatment. The CPZ and CPZ+AGM treatments significantly increased thiobarbituric acid reactive substances (TBARS), the nitrite and nitrate (NO₂+NO₃) concentration, and superoxide anion (O₂^•-) production in rat liver homogenates compared with C values. CPZ injection decreased the capacity of the antioxidant defense system: superoxide dismutase (SOD) activity, catalase (CAT) activity, total glutathione (GSH) content, glutathione peroxidase (GPx) activity, and glutathione reductase (GR) activity compared with the values of the C group. However, treatment with AGM increased antioxidant capacity in the rat liver; it increased the CAT activity, GSH concentration, GPx activity, and GR activity compared with the values of the CPZ rats. Immunohistochemical staining of ED1 in rats showed an increase in the number of positive cells 48 h after acute CPZ administration compared with the C group. Our results showed that AGM has no protective effects on parameters of oxidative and/or nitrosative stress in the liver but that it absolutely protective effects on the antioxidant defense system and restores the antioxidant capacity in liver tissue after administration of CPZ.

Experimental treatment of antipsychotic-induced movement disorders

Antipsychotic drugs are extensively prescribed for the treatment of schizophrenia and other related psychiatric disorders. These drugs produced their action by blocking dopamine (DA) receptors, and these receptors are widely present throughout the brain. Therefore, extended antipsychotic use also leads to severe extrapyramidal side effects. The short-term effects include parkinsonism and the later appearing tardive dyskinesia. Currently available treatments for these disorders are mostly symptomatic and insufficient, and are often linked with a number of detrimental side effects. Antipsychotic-drug-induced tardive dyskinesia prompted researchers to explore novel drugs with fewer undesirable extrapyramidal side effects. Preclinical studies suggest a role of 5-hydroxytryptamine (serotonin)-1A and 2A/2C receptors in the modulation of dopaminergic neurotransmission and motivating a search for better therapeutic strategies for schizophrenia and related disorders. In addition, adjunctive treatment with antioxidants such as vitamin E, red rice bran oil, and curcumin in the early phases of illness may prevent additional oxidative injury, and thus improve and prevent further possible worsening of related neurological and behavioral deficits in schizophrenia. This review explains the role of serotonergic receptors and oxidative stress, with the aim of providing principles for prospect development of compounds to improve therapeutic effects of antischizophrenic drugs.

Oxidative Stress Implications in the Affective Disorders: Main Biomarkers, Animal Models Relevance, Genetic Perspectives, and Antioxidant Approaches

The correlation between the affective disorders and the almost ubiquitous pathological oxidative stress can be described in a multifactorial way, as an important mechanism of central nervous system impairment. Whether the obvious changes which occur in oxidative balance of the affective disorders are a part of the constitutive mechanism or a collateral effect yet remains as an interesting question. However it is now clear that oxidative stress is a component of these disorders, being characterized by different aspects in a disease-dependent manner. Still, there are a lot of controversies regarding the relevance of the oxidative stress status in most of the affective disorders and despite the fact that most of the studies are showing that the affective disorders development can be correlated to increased oxidative levels, there are various studies stating that oxidative stress is not linked with the mood changing tendencies. Thus, in this minireview we decided to describe the way in which oxidative stress is involved in the affective disorders development, by focusing on the main oxidative stress markers that could be used mechanistically and therapeutically in these deficiencies, the genetic perspectives, some antioxidant approaches, and the relevance of some animal models studies in this context.

Evidence of activation of the Toll-like receptor-4 proinflammatory pathway in patients with schizophrenia

BACKGROUND

Alterations in the innate immune/inflammatory system may underlie the pathophysiology of schizophrenia, but we do not understand the mechanisms involved. The main agents of innate immunity are the Toll-like receptors (TLRs), which detect molecular patterns associated with damage and pathogens. The TLR first reported was TLR4, and it is still the most studied one.

METHODS

We aimed to describe putative modifications to the TLR4 proinflammatory pathway using 2 different strategies in 2 cohorts of patients with schizophrenia and matched controls: 1) quantification of protein and mRNA expression in postmortem prefrontal cortex samples from 30 patients with schizophrenia and 30 controls, and 2) identification of single nucleotide polymorphisms associated with the risk of schizophrenia using whole blood samples from 214 patients with schizophrenia and 216 controls.

RESULTS

We found evidence of alterations in the expression of the initial elements of the TLR4 signalling pathway (TLR4, Myeloid differentiation primary response gene 88 [MyD88] and nuclear factor-κ B [NF-κB]) in the PFC of patients with schizophrenia. These alterations seem to depend on the presence/absence of antipsychotic treatment at death. Moreover, a polymorphism within the MyD88 gene was significantly associated with schizophrenia risk.

LIMITATIONS

The use of 2 different approaches in 2 different cohorts, the lack of a complementary neuropsychiatric group, the possible confounding effects of antipsychotic treatment and suicide are the main limitations of our study.

CONCLUSION

The evidence from this dual approach suggests there is an altered innate immune response in patients with chronic schizophrenia in which the TLR4 proinflammatory pathway could be affected. Improved understanding of the stimuli and mechanisms responsible for this response could lead to improved schizophrenia treatment and better control of the side effects of current antipsychotics.

Combining the Antipsychotic Drug Haloperidol and Environmental Enrichment after Traumatic Brain Injury Is a Double-Edged Sword

Environmental enrichment (EE) confers significant benefits after experimental traumatic brain injury (TBI). In contrast, the antipsychotic drug (APD) haloperidol (HAL) exerts deleterious effects on neurobehavioral and cognitive recovery. Neurorehabilitation and management of agitation, however, are integral components of the treatment strategy for patients with TBI. Hence, the goal of this study was to determine how the two therapeutic approaches interact and influence motor and cognitive recovery. Anesthetized adult male rats received a controlled cortical impact (2.8 mm tissue deformation at 4 m/sec) or sham injury and then were provided HAL (0.5 mg/kg; intraperitoneally [IP]) or vehicle (VEH; 1 mL/kg; IP) commencing 24 h after surgery and once daily for 19 days while housed in EE or standard (STD) conditions. Beam balance/walk and Morris water maze performance were assessed on post-injury days 1-5 and 14-19, respectively, followed immediately by quantification of cortical lesion volumes. The data revealed both expected and unexpected findings. It was not surprising that the TBI groups receiving EE performed significantly better than those in STD housing and that the TBI + STD + HAL group performed worse than the TBI + STD + VEH group (p < 0.05). What was surprising was that the therapeutic effects of EE were greatly reduced by concomitant administration of HAL. No differences in cortical lesion volumes were observed among the groups (p > 0.05). The potential clinical implications of these findings suggest that administering HAL to patients undergoing neurorehabilitation may be a double-edged sword because agitation must be controlled before rehabilitation can be safely initiated and executed, but its use may compromise therapeutic efficacy.

Effects of antipsychotic drug administration on antioxidative defense enzymes in male rat kidney

The use of atypical antipsychotic drugs (APD) was reported to be associated with adverse effects on the kidneys. Thus, the aim of this study was to examine whether APD exerted their adverse effects by interfering with the renal antioxidant defense system. Male 3-mo-old Wistar rats were treated for 28 d with ziprasidone (ZIP), clozapine (CLO), or sertindole (SER) using a daily dose recommended for antipsychotic drug therapy. The expression and activities of antioxidant enzymes superoxide dismutase (SOD) type 1 and type 2, catalase (CAT), glutathione reductase (GR), and glutathione S-transferases (GSTs) activity were measured in the kidneys. Changes in the kidneys were also evaluated histologically. Ziprasidone, CLO, and SER reduced renal SOD type 1 and type 2 activities. Decreased CAT activity was observed only in SER-treated rats. An inhibition in GR activity and increased activity of GST was found only after treatment with CLO. Histological analysis showed dilatation of proximal tubules in kidneys with all three drugs. In conclusion, data indicate that redox disturbances may contribute to renal morphologic alterations in proximal tubules in rats treated with all APD.

Agomelatine Protection in an LPS-Induced Psychosis-Relevant Behavior Model

BACKGROUND The aim of this study was to investigate the effect of agomelatine in a psychosis-relevant behavior model. MATERIAL AND METHODS We used 18 adult male Wistar rats in this study. Twelve rats given LPS for endotoxemia were randomly divided into 2 groups (n=6). Group I was treated with 1 mL/kg 0.9% NaCl i.p. and Group II was treated with 40 mg/kg agomelatine. Six normal rats served as the control group and were not given LPS for endotoxemia. Cylindrical steel cages containing vertical and horizontal metal bars with top cover were used. Rats were put in these cages for the purpose of orientation for 10 min. Apomorphine was given to rats removed from cages, and then they were immediately put back in the cages for the purpose of observing stereotyped conduct. Brain HVA levels and plasma TNF-a levels were evaluated in tissue homogenates using ELISA. The proportion of malondialdehyde (MDA) was measured in samples taken from plasma for detection of lipid peroxidation similar to thiobarbituric acid reactive substances. RESULTS LPS induced-plasma TNF-α, brain TNF-α, and plasma MDA levels were significantly lower in the LPS+agomelatine group compared to the LPS+saline group (p<0.05). HVA levels and stereotype scores were significantly lower in the LPS+agomelatine group compared to the LPS+saline group (p <0.001). CONCLUSIONS Agomelatine reduced TNF-α, HVA, MDA levels, and the stereotype score in relevant models of psychosis. Our results suggest that the anti-inflammatory effect of agomelatine involved oxidant cleansing properties and that its effects on the metabolism of dopamine can play an important role in the model of psychosis.

Incidence of Neutropenia With Valproate and Quetiapine Combination Treatment in Subjects With Acquired Brain Injuries

OBJECTIVE

To investigate whether the incidence of neutropenia was higher in subjects who received a combination treatment with valproate and quetiapine than in those who were administered monotherapy.

DESIGN

Retrospective cohort study.

SETTING

Rehabilitation department of a university hospital.

PARTICIPANTS

Patients with acquired brain injuries who had taken valproate for seizures or quetiapine for delirium for >7 days (N=101). Data were extracted from electronic medical records of the hospital.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Incidence of neutropenia (absolute neutrophil count<2000 cells/μL) was elicited from the weekly complete blood cell records for 71.07±43.71 days of observation. The odds ratio for neutropenia development was calculated and adjusted for variables that showed significant differences between patients with or without neutropenia.

RESULTS

The incidence of neutropenia was significantly higher in the group receiving the combination treatment than in those receiving the monotherapy (32.26% vs 12.90%, adjusted P=.036), despite a lack of any differences in the daily doses of the medications. Coadministration of quetiapine and valproate was the predictor of neutropenia development when age, body weight, and underlying diseases were adjusted in the logistic regression model (odds ratio=3.749; 95% confidence interval, 1.161-12.099; P=.027).

CONCLUSIONS

Administration of quetiapine together with valproate in patients with acquired brain injury could increase the incidence of medication-induced neutropenia.

Increased oxidative stress and oxidative DNA damage in non-remission schizophrenia patients

Increasing evidence shows that oxidative stress plays a role in the pathophysiology of schizophrenia. But there is not any study which examines the effects of oxidative stress on DNA in schizophrenia patients. Therefore we aimed to assess the oxidative stress levels and oxidative DNA damage in schizophrenia patients with and without symptomatic remission. A total of 64 schizophrenia patients (38 with symptomatic remission and 26 without symptomatic remission) and 80 healthy volunteers were included in the study. 8-hydroxydeoxyguanosine (8-OHdG), total oxidant status (TOS) and total antioxidant status (TAS) were measured in plasma. TOS, oxidative stress index (OSI) and 8-OHdG levels were significantly higher in non-remission schizophrenic (Non-R-Sch) patients than in the controls. TOS and OSI levels were significantly higher in remission schizophrenic (R-Sch) patients than in the controls. TAS level were significantly lower and TOS and OSI levels were significantly higher in R-Sch patients than in Non-R-Sch patients. Despite the ongoing oxidative stress in patients with both R-Sch and Non-R-Sch, oxidative DNA damage was higher in only Non-R-Sch patients compared to controls. It is suggested that oxidative stress can cause the disease via DNA damage, and oxidative stress plays a role in schizophrenia through oxidative DNA damage.

Melanogenesis and antioxidant defense system in normal human melanocytes cultured in the presence of chlorpromazine

Chlorpromazine is used in the treatment of schizophrenia and psychotic disorders and belongs to phenothiazine class of neuroleptic drugs. It shows severe side effects such as extrapyramidal symptoms as well as ocular and skin disorders, but the mechanism is still not fully established. The aim of this study was to examine the effect of chlorpromazine on cell viability, melanogenesis and antioxidant defense system in normal human melanocytes. It has been demonstrated that chlorpromazine induces concentration dependent loss in cell viability. The value of EC(50) was calculated to be 2.53 μM. Chlorpromazine in lower concentrations (0.0001, 0.001 and 0.01 μM) increased the melanin and microphthalmia-associated transcription factor (MITF) content and tyrosinase activity, while changes of antioxidant enzymes activity were not observed. It suggests that long-term chlorpromazine therapy, even with low drug doses, may lead to hyperpigmentation disorders in skin and/or eye. The use of the analyzed drug in higher concentrations (0.1 and 1.0 μM) caused significant alterations of antioxidant enzymes activity in normal melanocytes, what may explain a potential role of chlorpromazine in the depletion of cellular antioxidant status leading to other adverse effects associated with the high-dose and/or long-term therapy.