Antipsychotic drugs scavenge radiation-induced hydroxyl radicals and intracellular ROS formation, and protect apoptosis in human lymphoma U937 cells

The mitochondria in schizophrenia with 22q11.2 deletion syndrome: From pathogenesis to therapeutic promise of targeted natural drugs

Schizophrenia is a complex multi-factor neurological disorder that caused an array of severe indelible consequences to the individuals and society. Additionally, anti-schizophrenic drugs are unsuitable for treating negative symptoms and have more significant side effects and drug resistance. For better treatment and prevention, we consider exploring the pathogenesis of schizophrenia from other perspectives. A growing body of evidence of 22q11.2 deletion syndrome (22q11DS) suggested that the occurrence and progression of schizophrenia are related to mitochondrial dysfunction. So combing through the literature of 22q11DS published from 2000 to 2023, this paper reviews the mechanism of schizophrenia based on mitochondrial dysfunction, and it focuses on the natural drugs targeting mitochondria to enhance mitochondrial function, which are potential to improve the current treatment of schizophrenia.

The effect of anticonvulsants on survival among patients with GBM brain tumors undergoing radiation: A SEER-Medicare analysis

BACKGROUND

Patients with glioblastoma multiforme (GBM) who undergo radiation often require anticonvulsants during treatment. The aim of this study was to determine the effects of anticonvulsants on GBM clinical outcomes.

METHODS

A retrospective analysis was performed using the SEER-Medicare database. All patients with GBM who were treated with radiation and concurrently taking an anticonvulsant were included in final analysis. Each class of medication was further subdivided by mechanism of action. Descriptive statistics were performed for all variables. Kaplan Meier survival curves were generated for each class of medication and Cox regression analysis was performed to assess the effect of each individual variable on survival.

RESULTS

There were 1561 patients available for final analysis. On multivariate Cox regression analysis, GBM patients taking sodium/calcium (Na/Ca) channel blocker anticonvulsants during radiation therapy demonstrated both improved overall survival (OS) (HR, 0.799; 95% CI [0.716, 0.891]; P < 0.001) and cancer specific survival (CSS) (HR, 0.814; 95% CI [0.727, 0.911]; P < 0.001).

CONCLUSION

OS was significantly better in patients taking NA/Ca channel blockers among patients with GBM who were concurrently undergoing radiation therapy.

Systematic Review of the Therapeutic Role of Apoptotic Inhibitors in Neurodegeneration and Their Potential Use in Schizophrenia

Schizophrenia (SZ) is a deleterious brain disorder affecting cognition, emotion and reality perception. The most widely accepted neurochemical-hypothesis is the imbalance of neurotransmitter-systems. Depleted GABAergic-inhibitory function might produce a regionally-located dopaminergic and glutamatergic-storm in the brain. The dopaminergic-release may underlie the positive psychotic-symptoms while the glutamatergic-release could prompt the primary negative symptoms/cognitive deficits. This may occur due to excessive synaptic-pruning during the neurodevelopmental stages of adolescence/early adulthood. Thus, although SZ is not a neurodegenerative disease, it has been suggested that exaggerated dendritic-apoptosis could explain the limited neuroprogression around its onset. This apoptotic nature of SZ highlights the potential therapeutic action of anti-apoptotic drugs, especially at prodromal stages. If dysregulation of apoptotic mechanisms underlies the molecular basis of SZ, then anti-apoptotic molecules could be a prodromal therapeutic option to halt or prevent SZ. In fact, risk alleles related in apoptotic genes have been recently associated to SZ and shared molecular apoptotic changes are common in the main neurodegenerative disorders and SZ. PRISMA-guidelines were considered. Anti-apoptotic drugs are commonly applied in classic neurodegenerative disorders with promising results. Despite both the apoptotic-hallmarks of SZ and the widespread use of anti-apoptotic targets in neurodegeneration, there is a strikingly scarce number of studies investigating anti-apoptotic approaches in SZ. We analyzed the anti-apoptotic approaches conducted in neurodegeneration and the potential applications of such anti-apoptotic therapies as a promising novel therapeutic strategy, especially during early stages.

Apocynin-Tandospirone Derivatives Suppress Methamphetamine-Induced Hyperlocomotion in Rats with Neonatal Exposure to Dizocilpine

Accumulating evidence implicates oxidative stress as a potential pathophysiological mechanism of schizophrenia. Accordingly, we synthesized new chemicals using apocynin and tandospirone as lead compounds (A-2, A-3 and A-4). These novel compounds decreased reactive oxygen species (ROS) concentrations in vitro and reversed decreases in glutathione levels in the medial prefrontal cortex of rats transiently exposed to MK-801, an N-methyl-d-aspartate receptor antagonist, in the neonatal period. To determine whether A-2, A-3 and A-4 show behavioral effects associated with antipsychotic properties, the effects of these compounds on methamphetamine (MAP)-induced locomotor and vertical activity were examined in the model rats. A-2 and A-3, administered for 14 days around the puberty period, ameliorated MAP-induced hyperlocomotion in MK-801-treated rats in the post-puberty period, while A-4 suppressed MAP-induced vertical activity. These findings indicate that apocynin-tandospirone derivatives present anti-dopaminergic effects and may alleviate psychotic symptoms of schizophrenia.

Present and future antipsychotic drugs: a systematic review of the putative mechanisms of action for efficacy and a critical appraisal under a translational perspective

Antipsychotics represent the mainstay of schizophrenia pharmacological therapy, and their role has been expanded in the last years to mood disorders treatment. Although introduced in 1952, many years of research were required before an accurate picture of how antipsychotics work began to emerge. Despite the well-recognized characterization of antipsychotics in typical and atypical based on their liability to induce motor adverse events, their main action at dopamine D2R to elicit the "anti-psychotic" effect, as well as the multimodal action at other classes of receptors, their effects on intracellular mechanisms starting with receptor occupancy is still not completely understood. Significant lines of evidence converge on the impact of these compounds on multiple molecular signaling pathways implicated in the regulation of early genes and growth factors, dendritic spine shape, brain inflammation, and immune response, tuning overall the function and architecture of the synapse. Here we present, based on PRISMA approach, a comprehensive and systematic review of the above mechanisms under a translational perspective to disentangle those intracellular actions and signaling that may underline clinically relevant effects and represent potential targets for further innovative strategies in antipsychotic therapy.

Anthocyanins from Aristotelia chilensis Prevent Olanzapine-Induced Hepatic-Lipid Accumulation but Not Insulin Resistance in Skeletal Muscle Cells

Type 2 diabetes and obesity are major problems worldwide and dietary polyphenols have shown efficacy to ameliorate signs of these diseases. Anthocyanins from berries display potent antioxidants and protect against weight gain and insulin resistance in different models of diet-induced metabolic syndrome. Olanzapine is known to induce an accelerated form of metabolic syndrome. Due to the aforementioned, we evaluated whether delphinidin-3,5-O-diglucoside (DG) and delphinidin-3-O-sambubioside-5-O-glucoside (DS), two potent antidiabetic anthocyanins isolated from Aristotelia chilensis fruit, could prevent olanzapine-induced steatosis and insulin resistance in liver and skeletal muscle cells, respectively. HepG2 liver cells and L6 skeletal muscle cells were co-incubated with DG 50 μg/mL or DS 50 μg/mL plus olanzapine 50 μg/mL. Lipid accumulation was determined in HepG2 cells while the expression of p-Akt as a key regulator of the insulin-activated signaling pathways, mitochondrial function, and glucose uptake was assessed in L6 cells. DS and DG prevented olanzapine-induced lipid accumulation in liver cells. However, insulin signaling impairment induced by olanzapine in L6 cells was not rescued by DS and DG. Thus, anthocyanins modulate lipid metabolism, which is a relevant factor in hepatic tissue, but do not significantly influence skeletal muscle, where a potent antioxidant effect of olanzapine was found.

Antipsychotic clozapine binding to alpha-2-macroglobulin protects interacting partners against oxidation and preserves the anti-proteinase activity of the protein

In this study, the interaction between clozapine, an atypical antipsychotic drug, and alpha-2-macroglobulin (α₂M), a multipurpose anti-proteinase, was investigated under simulated (patho) physiological conditions using multiple spectroscopic techniques and molecular modeling. It was found that α₂M binds clozapine with a moderate affinity (the binding constant of 0.9 × 10⁵ M^-1 at 37 °C). The preferable binding site for both clozapine's atropisomers was revealed to be a large pocket at the interface of C and D monomer subunits of the protein. Hydrogen bonds and the hydrophobic effect were proposed as dominant forces in complex formation. The binding of clozapine did not induce significant conformational change of the protein, as confirmed by virtually unaltered α₂M secondary structure and anti-proteinase activity. However, both clozapine and α₂M shielded each other from the deleterious influence of strong oxidants: sodium hypochlorite and 2,2'-azobis-2-methyl-propanimidamide dihydrochloride (AAPH). Moreover, clozapine in a concentration range that is usually targeted in the plasma during patients' treatment effectively protected the anti-proteinase activity of α₂M under AAPH-induced free radical overproduction. Our results suggest that the cooperation between α₂M and clozapine may be a path by which these two molecules synergistically protect neural tissue against injury caused by disturbed proteostasis or oxidative stress.

Atypical antipsychotic clozapine binds fibrinogen and affects fibrin formation

Clozapine is an atypical antipsychotic used for the treatment of schizophrenia. The prescribed target daily doses may reach 900 mg. Literature studies report a connection between clozapine usage and thrombosis development. Our in vitro study aimed to provide insight into molecular bases of this observation, investigating clozapine binding to fibrinogen, the main plasma protein involved in hemostasis. Fibrinogen/clozapine interaction was confirmed by protein fluorescence quenching, with an affinity constant of 1.7 × 10⁵ M^-1. Direct interactions did not affect the structure of fibrinogen, nor fibrinogen melting temperature. Clozapine binding affected fibrin formation by reducing coagulation speed and thickness of fibrin fibers suggesting that in the presence of clozapine, fibrinogen may acquire thrombogenic characteristics. Although no difference in fibrin gel porosity was detected, other factors present in the blood may act synergistically with altered fibrin formation to modify fibrin clot, thus increasing the risk for development of thrombosis in patients on clozapine treatment. ORAC and HORAC assays showed that clozapine reduced free radical-induced oxidation of fibrinogen. All observed effects of clozapine on fibrinogen are dose-dependent, with the effect on fibrin formation being more pronounced.

Radioprotective effect of olanzapine as an anti-psychotic drug against genotoxicity and apoptosis induced by ionizing radiation on human lymphocytes

Olanzapine (OLA), is prescribed as an anti-psychotic medicine in schizophrenia patients. In this study, the protective effect of OLA against genotoxicity and apoptosis induced by ionizing radiation in human healthy lymphocytes was evaluated. At first, the antioxidant activities of OLA were assayed by two different methods as free radical scavenging with DPPH (2,2-diphenyl-1-picryl-hydrazyl) and ferric reducing power methods. In in vitro experiment, human blood samples were treated with OLA at various concentrations (0.25-20 μM) for 3 h and then were exposed to X-ray at a dose of 150 cGy. The genotoxicity was assessed in binucleated human lymphocytes with micronuclei assay. The apoptotic lymphocytes were assessed by flow cytometry in OLA treated and/or irradiated lymphocytes. OLA exhibited free radical scavenging and reducing power activities more than ascorbic acid. The results showed that the lymphocytes treated with OLA and later exposed to IR presented lower frequencies of micronuclei and apoptosis compared to the control sample which was irradiated and not treated to OLA. The maximum radioprotection was observed at 20 μM of OLA with 83% of efficacy. The present study suggested the protective role for OLA in protection radiation-induced genetic damage and apoptosis induced by ionizing irradiation in human normal cells.