UMLS:C0036341 - FACTA Search

Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036341 (schizophrenia)
60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We previously found that the atypical antipsychotic drugs (APDs) clozapine, olanzapine, quetiapine, and risperidone reduce PC12 cell death induced by hydrogen peroxide, N-methyl-4-phenylpyridinium ion, or beta-amyloid peptide (Abeta(25-35)). Such neurotoxic substances have in common the capability of causing oxidative stress. Atypical APDs have been used in treating schizophrenia and in treating psychotic symptoms of patients with Alzheimer's disease (AD), in which Abeta is involved by causing oxidative stress. Therefore, we hypothesized that atypical APDs might alleviate oxidative stress in PC12 cells, thus protecting them from apoptosis. PC12 cells were seeded in plates or chambers for 24 hr and cultured for another 24 hr with olanzapine or quetiapine in the medium, and then the cells were cultured in the new medium containing Abeta(25-35) and/or olanzapine, quetiapine, but not serum, for various periods. It was shown that cultures treated with olanzapine + Abeta(25-35), or quetiapine + Abeta(25-35), had significantly higher cell viabilities and lower rates of apoptosis compared with the cultures exposed only to Abeta(25-35). In addition, the drugs blocked the activation of caspase-3 caused by Abeta(25-35). Furthermore, olanzapine and quetiapine prevented Abeta(25-35)-induced overproduction of intracellular reactive oxygen species, Abeta(25-35)-induced decrease in mitochondrial membrane potential, and Abeta(25-35)-induced changes in activities of the key antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase. In consideration of the wealth of evidence linking oxidative stress to the pathophysiology of schizophrenia and AD, these findings give us a new insight into the therapeutic actions of atypical antipsychotics in patients with the disorders.
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PMID:Olanzapine and quetiapine protect PC12 cells from beta-amyloid peptide(25-35)-induced oxidative stress and the ensuing apoptosis. 1594 79

There is accumulating evidence of altered antioxidant enzyme activities and increased levels of lipid peroxidation in schizophrenia. Free radical-mediated abnormalities may contribute to specific aspects of schizophrenic symptomatology and complications of its treatment. However, few studies have evaluated both antioxidant enzymes and lipid peroxidation in the same schizophrenic patient groups treated with typical or atypical antipsychotics. Plasma malondialdehyde (MDA) levels and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities were analyzed using established procedures in 92 medicated schizophrenia including paranoid (n=34), disorganized (n=18) and residual subtypes (n=40), as well as in control subjects (n=50). The results showed that activities of SOD and GSH-Px were decreased but levels of MDA were elevated in patients with a chronic form of schizophrenia as compared with normal controls. SOD and GSH-Px activities were found to be significantly lower in paranoid and residual subtypes compared to both disorganized subtype and the control group. MDA levels were significantly higher in all subtypes compared to the control group. There were no significant differences in any parameters measured among all three subgroups treated with clozapine (n=44), risperidone (n=20) and typical antipsychotics (n=28). Additionally, a significantly higher MDA levels, but a significantly lower CAT activity was noted in female than male patients. These results suggest that oxidative stress may be implicated in the pathophysiology of all subtypes of schizophrenia, which may contribute to the increased membrane lipid peroxidation. Long-term treatments with typical and atypical antipsychotics may produce the similar effects on the antioxidant enzymes and lipid peroxidation.
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PMID:Antioxidant enzymes and lipid peroxidation in different forms of schizophrenia treated with typical and atypical antipsychotics. 1630 94

It has been suggested that the extract of gingko biloba (EGb) may enhance the efficiency of the classic antipsychotic haloperidol in patients with chronic schizophrenia, especially on positive symptoms, and reduce serum superoxide dismutase (SOD) levels. Therefore, we decided to evaluate the therapeutic effect of EGb and to examine the effect of it on the levels of antioxidant enzymes in schizophrenic patients on olanzapine treatment. We hypothesized that EGb would have the beneficial effects on schizophrenic symptoms and might cause reductions in antioxidant enzymes. The subjects were randomly assigned to the two groups: olanzapine plus EGb (group I) (n=15) and olanzapine alone (group II) (n=14). The patients were evaluated at baseline and at week 8 with respect to the Positive and Negative Syndrome Scale (PANSS), serum SOD, catalase (CAT), and glutathion peroxidase (GPX) levels. At baseline, no statistically significant difference regarding the mean total PANSS scores between treatment groups was found. At the evaluation of week 8, a significant difference in mean Scale for the Assessment of Postive Symptoms (SAPS) scores but not in Scale for the Assessment of Negative Symptoms scores between groups was found. Total patients had statistically significant higher serum SOD, CAT and GPX levels compared to control groups at baseline. At 8 weeks, there were significant differences in the mean decrease in SOD and CAT levels but not in GPX levels between treatment groups. The changes in SOD and CAT levels were correlated with the change in SAPS in group I, but not in the group II. The present study supported the findings of the previous study demonstrating that EGb might enhance the efficiency of antipsychotic in patients with schizophrenia, particularly on positive symptoms of the disorder.
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PMID:The effect of extract of ginkgo biloba addition to olanzapine on therapeutic effect and antioxidant enzyme levels in patients with schizophrenia. 1640 Dec 39

Short-term (<45 days) treatment studies in rats have reported increased oxidative stress and oxidative (i.e., oxygen free radical-mediated) neural cell injury with typical antipsychotics such as haloperidol, but not with the atypicals such as clozapine, olanzapine or risperidone. However, now these and several other atypical antipsychotics that differ in their neurotransmitter receptor affinity profiles are being used for a long-term treatment of schizophrenia. Therefore, understanding of their long-term treatment effects on the expression of antioxidant enzymes and oxidative neural cell injury in rats may be important to explain the possible differential mechanisms underlying their long-term clinical and side effects profiles. The effect of 90 and 180 day exposure to haloperidol (HAL, 2mg/kg/day), a representative typical antipsychotic was compared to exposure to chlorpromazine (CPZ, 10mg/kg/day), ziprasidone (ZIP, 12mg/kg/day), risperidone (RISP, 2.5mg/kg/day), clozapine (CLOZ, 20mg/kg/day) or olanzapine (OLZ, 10mg/kg/day) on the expression of antioxidant defense enzymes and levels of lipid peroxidation in the rat brain. The drug-induced effects on various antioxidant defense enzymes; manganese-superoxide dismutase (MnSOD), copper-zinc superoxide dismutase (CuZnSOD) and catalase (CAT) were assessed by determination of their enzymatic activity and protein content. Immunohistochemical analysis was also carried out to assess the cellular levels of MnSOD and CuZnSOD and cellular morphology. The oxidative membrane damage was assessed by determination of levels of the lipid peroxidation product, hydroxyalkanals (HAEs) in the rat brain. Both 90 and 180 days of HAL treatment very significantly decreased the levels of MnSOD (50%) and CuZnSOD (80%) and increased the levels of HAEs compared to vehicle treatment. Smaller reduction was found in CAT (25%) and no change in the glutathione peroxidase (GSHPx). The levels of enzymatic activity correlated generally well with the levels of enzyme protein indicating that the changes were in the expression of net protein. Though atypical antipsychotics like ZIP, RISP and OLZ did not show any change in the HAEs levels up to 90 days, further treatment up to 180 days resulted in significantly increased levels of HAEs in CPZ, ZIP and RISP, but not in OLZ treated rats. Post-treatment with several atypical antipsychotics (OLZ=CLOZ>RISP) for 90 days after 90 day of HAL treatment significantly restored the HAL-induced loss in MnSOD and CuZnSOD activities and increase in lipid peroxidation products as well as cellular morphology. These data may be very helpful in planning long-term use as well as switch over of these antipsychotics for the management of schizophrenia.
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PMID: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. 1656 57

Clozapine, an atypical antipsychotic drug effective in treatment of refractory schizophrenia causes potentially life-threatening agranulocytosis. The drug undergoes bioactivation to a toxic, chemically reactive intermediate with capacity to target stromal cells, central components of the bone marrow microenvironment implicated in neutrophil development. To identify possible mechanisms underpinning disruption of stroma as a site of drug bioactivation, toxicity was induced in vitro. Therefore metabolite generation procedures utilizing HOCl or HRP-H(2)O(2) as primary components involved in clozapine metabolism were adapted for stromal culture and coupled with viability determinations. Drug oxidation by HOCl was less toxic to stromal cells than HRP-H(2)O(2) based methods. More specifically, clozapine bioactivation by HRP-H(2)O(2) caused dose-dependent inhibition of stromal viability at therapeutically relevant concentrations. Differences in susceptibility of HAS303 and LP101 cells to the clozapine nitrenium ion were also evident. Stromal cell death was attributed to clozapine in the presence of a complete metabolising system comprising HRP and H(2)O(2). In the absence of a complete metabolising system clozapine was not cytotoxic. For LP101 cells, drug plus HRP (minus H(2)O(2)) also induced toxicity. Importantly, other antipsychotic drugs including risperidone, olanzapine and haloperidol when bioactivated, were not cytotoxic, indicating system specificity for clozapine. Exogenous GSH, N-acetylcysteine, l-ascorbic acid, catalase, and sodium azide afforded protection to cells whereas S-methylGSH, GSSG, ketoprofen and proadifen did not. Thus functional data derived from the in vitro stromal system defined in these studies may enable further investigation of the mechanisms subserving stromal impairment in clozapine-induced agranulocytosis and direct attention to improved methods for its prevention.
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PMID:Clozapine bioactivation induces dose-dependent, drug-specific toxicity of human bone marrow stromal cells: a potential in vitro system for the study of agranulocytosis. 1684 94

The aims of this study are to investigate the contribution effect of oxidative stress in MK-801-induced experimental psychosis model, and to show that prevention of oxidative stress may improve prognosis. Because oxidative damage has been suggested in the neuropathophysiology of schizophrenia, the possible protecting agents against lipid peroxidation are potential target for the studies in this field. For this purpose, Wistar Albino rats were divided into three groups: the first group was used as control, MK-801 was given to the rats in the second group and MK-801+omega-3 essential fatty acids (EFA) was given to the third group. MK-801 was given intraperitoneally at the dose of 0.5mg/(kgday) once a day for 5 days in experimental psychosis group. In the second group, 0.8g/(kgday), omega-3 FA (eicosapentaenoic acid, 18%, docosahexaenoic acid, 12%) was given to the rats while exposed MK-801. In control group, saline was given intraperitoneally at the same time. After 7 days, rats were killed by decapitation. Prefrontal brain area was removed for histological and biochemical analyses. As a result, malondialdehyde (MDA), as an indicator of lipid peroxidation, protein carbonyl (PC), as an indicator of protein oxidation, nitric oxide (NO) levels and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities as antioxidant enzymes, and xanthine oxidase (XO) and adenosine deaminase (AD) activities as an indicator of DNA oxidation was found to be increased significantly in prefrontal cortex (PFC) of MK-801 group (P<0.0001) compared to control group. In omega-3 FA treated rats, prefrontal tissue MDA, PC and NO levels as well as SOD, GSH-Px, XO, and AD enzyme activities were significantly decreased when compared to MK-801 groups (P<0.0001) whereas catalase (CAT) enzyme activity was not changed. Moreover, in the light of microscopic examination of MK-801 groups, a great number of apoptotic cells were observed. omega-3 FA supplementation decreased the apoptotic cell count in PFC. The results of this study revealed that oxidative stress and apoptotic changes in PFC may play an important role in the pathogenesis of MK-801-induced neuronal toxicity. This experimental study also provides some evidences for the protective effects of omega-3 FA on MK-801-induced changes in PFC of rats.
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PMID:The protective effects of omega-3 fatty acids against MK-801-induced neurotoxicity in prefrontal cortex of rat. 1697 Oct 21

The high rate of smoking in schizophrenia may reflect patients' attempts to reduce the side effects of antipsychotic medications, and one mechanism for this reduction may be a reduction in oxidative stress and free radical-mediated brain damage that may contribute to schizophrenic symptoms and to complications of its treatment. Symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS), side effects were assessed with the Simpson and Angus Rating Scale (SAS), and malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities were measured in plasma. All of these measures were compared in 130 male inpatients with DSM-IV schizophrenia: 104 smokers and 26 non-smokers. The results showed that the positive PANSS symptoms were lower in smokers than non-smokers (14.5 vs 17.5), while the negative symptoms were lower in those who smoked more cigarettes (r=-0.23). The SAS showed no differences. The CAT activity was correlated with both GSH-Px and SOD activities. Of the three enzymes only the CAT activity was significantly higher in smokers than non-smokers (2.9 vs 1.6 U/ml), but greater SOD activity correlated more cigarettes smoked (r=0.24). Consistent with some protection against oxidative stress, MDA also was significantly lower in smokers than non-smokers (9.2 vs 14.4 nmol/ml). The fewer positive symptoms in smokers and fewer negative symptoms in those who smoked more cigarettes may be a selection bias, but appears to be associated with decreased oxidative stress and lipid peroxidation in schizophrenics who smoke tobacco.
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PMID:Nicotine dependence, symptoms and oxidative stress in male patients with schizophrenia. 1722 36

MK-801 was shown to be one of the most neurotoxic non-competitive NMDA receptor antagonists. It is known that repeated injection of MK-801 was proposed in an animal model in psychosis. The aims of this study are to investigate the contributing effect of oxidative stress in MK-801-induced experimental psychosis model, and to show that prevention of oxidative stress may improve prognosis. Furthermore, there is evidence that oxygen free radicals play an important role in the pathophysiology of schizophrenia. In this study, Wistar Albino rats were divided into three groups: 1st group: Control, 2nd group: MK-801, 3rd group: MK-801+CAPE (Caffeic acid phenethyl ester) group. MK-801 was given intraperitoneally at the dose of 0.5 mg/kg/day for 5 days. CAPE was given to the treatment group while exposed to MK-801. In control group, saline was given intraperitoneally at the same time. After 7 days, rats were killed by decapitation. Prefrontal cortex (PFC) of rats was removed for biochemical and histological analyses. As a result, malondialdehyde (MDA), protein carbonyl (PC), nitric oxide (NO) levels and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and xanthine oxidase (XO) and adenosine deaminase (AD) enzyme activities were found to be increased significantly in prefrontal cortex (PFC) of MK-801 group (p<0.0001) compared to control group. In CAPE treated rats, prefrontal tissue MDA, PC, NO levels and, GSH-Px, XO, AD enzyme activities were significantly decreased when compared to MK-801 groups (p<0.0001) whereas catalase (CAT) enzyme activity was not changed. Moreover, in the light of microscopic examination of MK-801 groups, a great number of apoptotic cells were observed. CAPE treatment decreased the apoptotic cell count in PFC. The results of this study showed that MK-801-induced neurotoxicity caused oxidative stress in PFC of rats. This experimental study may also provide some evidences for the new treatment strategies with antioxidants in schizophrenia.
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PMID:Oxidative stress in prefrontal cortex of rat exposed to MK-801 and protective effects of CAPE. 1737 54

The occurrence and irreversibility of tardive dyskinesia (TD), a motor disorder of the orofacial region, resulting from chronic neuroleptic treatment has been considered a major clinical issue in the treatment of schizophrenia. The molecular mechanism underlying the pathophysiology of TD is not completely known. Several animal studies have demonstrated an enhancement of oxidative damage and increased glutamatergic transmission after chronic administration of neuroleptics. The present study investigated the effect of rutin, an antioxidant in haloperidol-induced orofacial dyskinesia by using different behavioural (orofacial dyskinetic movements, stereotypic rearing, locomotor activity, percent retention), biochemical [lipid peroxidation, reduced glutathione levels, antioxidant enzyme levels (SOD and catalase)] and neurochemical (neurotransmitter levels) parameters. Chronic administration of haloperidol (1 mg/kg i.p. for 21 days) significantly increased vacuous chewing movements, tongue protrusions and facial jerking in rats, which were significantly inhibited by rutin. Chronic administration of haloperidol also resulted in dopamine receptor sensitivity as evident by a well-shaped response (initial decrease followed by increase) in locomotor activity and stereotypic rearing and also decreased percent retention time on elevated plus maze paradigm. Pretreatment with rutin reversed these behavioural changes. Besides, haloperidol also induced oxidative damage in all regions of brain which was prevented by rutin, especially in the subcortical region containing striatum. Although turnover of dopamine and noradrenaline decreased in both cortical and subcortical regions after chronic administration of haloperidol, it was significantly reversed by high-dose rutin treatment. The findings of the present study suggested the involvement of free radicals in the development of neuroleptic-induced orofacial dyskinesia, a putative model of TD, and rutin as a possible therapeutic option to treat this hyperkinetic movement disorder.
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PMID:Protective effect of rutin, a polyphenolic flavonoid against haloperidol-induced orofacial dyskinesia and associated behavioural, biochemical and neurochemical changes. 1786 5

Tardive dyskinesia (TD) is a motor disorder of the orofacial region resulting from chronic neuroleptic treatment. A high incidence and irreversibility of this hyperkinetic disorder has been considered a major clinical issue in the treatment of schizophrenia. The molecular mechanism related to the pathophysiology of tardive dyskinesia is not completely known. Various animal studies have demonstrated an enhanced oxidative stress and increased glutamatergic transmission as well as inhibition in the glutamate uptake after the chronic administration of haloperidol. The present study investigated the effect of curcumin, an antioxidant, in haloperidol-induced tardive dyskinesia by using different behavioural (orofacial dyskinetic movements, stereotypy, locomotor activity, % retention), biochemical (lipid peroxidation, reduced glutathione levels, antioxidant enzyme levels (SOD and catalase) and neurochemical (neurotransmitter levels) parameters. Chronic administration of haloperidol (1 mg/kg i.p. for 21 days) significantly increased vacuous chewing movements (VCM's), tongue protrusions, facial jerking in rats which was dose-dependently inhibited by curcumin. Chronic administration of haloperidol also resulted in increased dopamine receptor sensitivity as evident by increased locomotor activity and stereotypy and also decreased % retention time on elevated plus maze paradigm. Pretreatment with curcumin reversed these behavioral changes. Besides, haloperidol also induced oxidative damage in all major regions of brain which was attenuated by curcumin, especially in the subcortical region containing striatum. On chronic administration of haloperidol, there was a decrease in turnover of dopamine, serotonin and norepinephrine in both cortical and subcortical regions which was again dose-dependently reversed by treatment with curcumin. The findings of the present study suggested for the involvement of free radicals in the development of neuroleptic-induced tardive dyskinesia and point to curcumin as a possible therapeutic option to treat this hyperkinetic movement disorder.
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PMID:Protective effect of Curcumin, the active principle of turmeric (Curcuma longa) in haloperidol-induced orofacial dyskinesia and associated behavioural, biochemical and neurochemical changes in rat brain. 1802 80

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