Alteration Of Oxidative Stress In Peripheral Blood Of First-episode Schizophrenia Patients Before And After Treatment

BackgroundSchizophrenia is a kind of severe complicated mental desease which is characterized by repeated episodes,long ill course and high morbidity,which often takes serious impact on health and quality of life of patients.But the exact etiology and pathogenesis at present is unknown.There is already sufficient clinical evidence that dopamine(DA)nervous system dysfunction is associated with the development of schizophrenia.Dopamine is a powerful oxidant which catalyze free radical generation through its own oxidation or monoamine oxidase and then enhence membrane lipid peroxidation,affecting neuronal plasticity,cell signaling and metabolism of neurotransmitters of the body.The process may lead to neurological deficits and then mental symptoms appears.There are increasing evidence that oxidative stress and free radicals are related to the pathogenesis of SZ recent years.ObjectivesTo observe the alteration of plasma oxidative stress parameters including total superoxide dismutase(T-SOD),glutathione peroxidase(GSH-Px),catalase(CAT)and total antioxidant capacity(T-AOC)of first-episode schizophrenia patients(FEP)in comparation of the controls and the effects of single atypical antipsychotic on oxidative stress before and after treatment witn risperidone or olanzapine(each group therapy respectively)in first-episode schizophrenia patients compared with controls in order to explore the correlation between oxidative stress and the onset of schizophrenia,and the effect of treatment of antipsychotic medication on oxidative stress.MethodsForty-seven first-episode schizophrenia patients(FEP)who all met The international classification of diseases-10 were recruited from Henan Mental Hospital.27 males and 20 females whose age were ranged from 16 to 45 years old were included and,the average age was(26.43±7.49)years old.Forty-three controls were recruited from from the surrounding communities who came to Henan Mental Hospital to have healthy examination.24 male and 19 females whose age were ranged from 16 to 45 years old were included and the average age was(27.65±5.73)years old.The two groups were sex(χ2=0.000,P=1.000)and age(T=-0.866,P=0.389)matched.Blood samples were drawn at about 7:00 a.m.At the assigning for the two grouss and after 6-8 weeks’ treatment for the case group to determine plasma total superoxide dismutase(T-SOD),glutathione peroxidase(GSH-Px),catalase(CAT)and total antioxidant capacity(T-AOC)by spectrophotometry.Assessed the patients with PANSS(positive and negative syndrome scale)at the same time with blood drawing before and after treatment.The data was analyzed by SPSS 22.0 statistical software.Pearson correlation analysis was used to observe the age and culture education years with the parameters of oxidative stress for case group and control group and the correlations among oxidative stress parameters,total score and each score of P,N,G of PANSS;independent samples t-test was used to observe correlations between the each parameter in case and control group;paired samples t test was used to observe comparation before and after treatmet with risperidone and olanzapine.All statistical tests were two-sided test,the difference was ststistically significant(P<0.05).Results1.GSH-Px and CAT were positively correlated(r = 0.323,P = 0.035),also T-AOC and CAT were also positively correlated(r = 0.351,P = 0.021)in control group;T-SOD and T-AOC was negative correlated(r=-0.443,P = 0.002)at the same time GSH-Px and T-AOC also showed a negative correlation(r=-0.296,P = 0.046)in case group 2.The activity of T-SOD(P=0.019),GSH-Px(P=0.000)were lower and CAT(P=0.018)was higher in FEP compared to the control group3.there was no significant correlation between OS parameters and total scores or P、N、G of PANSS(P>0.05)4.T-SOD(P=0.020)was improved in risperidone group after treatment;T-AOC(P=0.034)in olanzapine group was improved after treatment ConclusionsOxidative stress exists in the pathogenesis of schizophrenia.There is alteration of antioxidant enzyme activities in first episode of schizophrenia patients.The antioxidant capacity of the body is decreased with the increasing amount of free radicals.The body is in a state of oxidative stress,with lipid peroxidation,changes of structure and permeability of cell membrane,which may affect the transfer of neurotransmitters and signal transduction pathways,which may be related to the pathological mechanism of schizophrenia.Atypical antipsychotic drug risperidone and olanzapine both can improve the clinical symptoms of the patients,and the oxidative stress parameters also obteined a certain degree of improvement,showing that the oxidative stress damage caused by free radical may possibly play a role in onset of schizophrenia.Atypical antipsychotic drugs may likely to exert an antioxidant effect through the improvement of oxidative stress,providing a theoretical basis for the clinical use of antioxidants to prevent or treat mental disorders.