The Oxidative Stress May be Induced by the Elevated Homocysteine in Schizophrenic Patients

Abstract

The mechanisms of oxidative stress in schizophrenic patients are not fully understood. In the present study, we investigated the effect of elevated level of homocysteine (Hcys) on some parameters of oxidative stress, namely thiobarbituric acid reactive substances (TBARS), an index of lipid peroxidation in plasma, the level of carbonyl groups in plasma proteins, as well as the amount of 3-nitrotyrosine in plasma proteins isolated from schizophrenic patients. Patients hospitalised in I and II Psychiatric Department of Medical University in Lodz, Poland were interviewed with special questionnaire (treatment, course of diseases, dyskinesis and other EPS). According to DSM-IV criteria all patients had diagnosis of paranoid type. They were treated with antipsychotic drugs (clozapine, risperidone, olanzapine). Mean time of schizophrenia duration was about 5 years. High-performance liquid chromatography was used to analyse the total level of homocysteine in plasma. Levels of carbonyl groups and 3-nitrotyrosine residues in plasma proteins were measured by ELISA and a competition ELISA, respectively. The lipid peroxidation in plasma was measured by the level of TBARS. Our results showed that in schizophrenic patients the amount of homocysteine in plasma was higher in comparison with the control group. We also observed a statistically increased level of biomarkers of oxidative/nitrative stress such as carbonyl groups or 3-nitrotyrosine in plasma proteins from schizophrenic patients. Moreover, our experiments indicate that the correlation between the increased amount of homocysteine and the oxidative stress exists. Considering the data presented in this study, we suggest that the elevated Hcys in schizophrenic patients may stimulate the oxidative stress.

Increased Oxidant Stress and Inflammation in Patients with Chronic Schizophrenia

“…In agreement with our findings, other authors reported that schizophrenic patients in their study groups also had folate and B12 levels within normal limits [28]. These findings suggest that the patients in our study group were not undernourished.…”

Oxidative Stress and Schizophrenia

“…Through the clinical studies of hospitalized schizophrenia selected from an average disease duration of 5 years treated with second antipsychotic drugs during therapy, DietrichMuszalska, et al [4] found that carbonyl groups and 3-nitrotyrosine were significantly higher in the experimental group thans the normal control group. Herken, et al [5] and Al-Chalabi, et al [6] found that erythrocyte thiobarbituratic acid reactive substances (TBARS) in chronic schizophrenics treated with stable daily doses of neuroleptics and serum malondiadehyde (MDA) in patients newly diagnosed with schizophrenia were significantly increased, respectively.…”

Cognitive Impairment of Chronic Alcohol Dependence and Its Relationship with Prefrontal Cortex

“…Through the clinical studies of hospitalized schizophrenia selected from an average disease duration of 5 years treated with second antipsychotic drugs during therapy, DietrichMuszalska, et al [4] found that carbonyl groups and 3-nitrotyrosine were significantly higher in the experimental group thans the normal control group. Herken, et al [5] and Al-Chalabi, et al [6] found that erythrocyte thiobarbituratic acid reactive substances (TBARS) in chronic schizophrenics treated with stable daily doses of neuroleptics and serum malondiadehyde (MDA) in patients newly diagnosed with schizophrenia were significantly increased, respectively.…”