OBJECTIVETo examine changes of blood oxidative-antiovidative level in schizophrenic patients and its relationship with clinical symptoms.

METHODSForty-six Chinese patients met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders-IV) criteria for schizophrenia and fifty age- and sex-matched healthy controls were enrolled in the present study. Baseline psychiatric symptom severity was assessed with brief psychiatric rating scale, positive and negative syndrome scale on the blood draw day. Fresh blood samples were collected to measure levels of nitric oxide and lipid peroxide in plasma as well as activities of superoxide dismutase, catalase and glutathione peroxidase in red blood cells by spectrophotometric assays simultaneously.

RESULTSComparison of the biochemical parameters indicated that the level of nitric oxide and lipid peroxide increased in patient group, which represented a positive correlation with positive scale scores; while the activities of three critical enzymes decreased and showed a negative linear correlation.

CONCLUSIONThis study showed that there are dysregulation of free radical metabolism and poor activities of the antioxidant defense systems in schizophrenic patients. Excess free radicals formation may play a critical role in the etiology of schizophrenia. Using antioxidants might be an effective therapeutic approach to partially alleviate or prevent the symptoms of schizophrenia.

Adolescent ; Adult ; Antioxidants ; metabolism ; Female ; Free Radicals ; Humans ; Lipid Peroxides ; metabolism ; Male ; Middle Aged ; Nitric Oxide ; metabolism ; Schizophrenia ; etiology ; metabolism

OBJECTIVETo study the relationship between abnormal reactions of free radicals in bodies of patients with acute organophosphorus pesticide poisoning (AOPP) and damages induced by free radicals.

METHODS58 AOPP patients and 58 healthy adult volunteers (HAV) were enrolled in an independent samples control design, in which spectrophotometric methods were used to determine the concentrations of nitric oxide (NO) and lipoperoxides (LPO) in plasma, and LPO in erythrocytes, vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and acetylcholinesterase (AChE) in erythrocytes.

RESULTSCompared with the average values of every biochemical parameter in the HAV group, the average values of LPO in plasma and in erythrocytes, and NO in plasma in the AOPP group were significantly increased (P = 0.000001), while the average values of VC, VE, beta-CAR in plasma as well as SOD, CAT, GSH-Px and AChE in erythrocytes in the AOPP group were significantly decreased (P = 0.000001). The findings of Pearson product-moment correlation analysis between the value of AChE in erythrocytes and the values of above biochemical parameters for 58 AOPP patients showed that there was a significant linear negative correlation between AChE in erythrocytes and LPO, NO in plasma, and LPO in erythrocytes (P = 0.000001-0.001319), while there was a significant linear positive correlation between AChE in erythrocytes and VC, VE, beta-CAR in plasma as well as SOD, CAT, GSH-Px in erythrocytes (P = 0.000013-0.000824). The results of discriminant analysis of above chemical parameters for 58 AOPP patients and 58 HAV suggested that the correct rates of discriminant analysis were increased to 100% when the values of AChE and LPO in plasma and in erythrocytes, or AChE and others, were jointly used for the discriminant analysis.

CONCLUSIONThe findings of the present study suggest that a series of free radical reactions in AOPP patients' bodies are pathologically aggravated, and the discriminant analysis used the above biochemical parameters could markedly increase its correct rates for AOPP patients.

Acute Disease ; Adolescent ; Adult ; Female ; Free Radicals ; blood ; Humans ; Lipid Peroxides ; blood ; Male ; Nitric Oxide ; blood ; Organophosphate Poisoning ; Pesticides ; poisoning ; Poisoning ; blood

The patients with end stage renal disease show several complications such as artherosclerosis, anemia and increased susceptibility to infection by damage due to oxygen free radicals. Superoxide dismutase(SOD) is directly linked to the fate of the highly reactive oxygen metabolites. If there is an alteration in the activity of SOD, this alteration may contribute to the complications by reactive oxygen species in patients with end stage renal disease. In this experiment, SOD activity and the effect of cyanate on the activity of SOD was studied to understand the mechanism of several complications mediated by oxygen free radicals in patients with end stage renal disease. SOD activity in the plasma and erythrocytes from patients with end stage renal disease was significantly lower than those from healthy controls. It is known that underproduction of SOD leads to excess production of superoxide and reduced iron favoring hydroxyl radical formation. The results in this experiment suggest that there is an overproduction of superoxide anion in patients with end stage renal disease. The overproduction of superoxide anion may contribute the patients with end stage renal disease susceptible to oxidant damages. To evaluate if cyanate could carbamylate SOD, SOD was incubated with cyanate. The level of carbamylated SOD increased as the time of exposure to cyanate increased from 0 hour to 72 hours. Furthermore, the degree of carbamylation of SOD increased as cyanate concentration in the incubation media rose from 20mM to 1M. There appears to be a maximum degree of carbamylation at a concentration of 1,000mM cyanate. To test the hypothesis that in vitro carbamylation of SOD alters its biological activity, SOD activity was measured after incubation with cyanate. The activity of carbamylated SOD decreased as the time of exposure to cyanate increased from 0 hour to 72 hours. Furthermore, the activity of carbamylated SOD decreased as cyanate concentration in the incubation media rose from 20mM to 1M and when albumin was added to the reaction mixture, the loss of SOD activity was prevented. These results are consistent with the hypothesis that SOD is also carbamylated and lost biological activity in end stage renal disease patients by cyanate, and that the degree of carbamylation depends on both the concentration of cyanate and the length of exposure. Also, these suggest that albumin may prevent carbamylation of SOD at least in vitro condition.
Anemia ; Erythrocytes ; Free Radicals ; Humans ; Hydroxyl Radical ; Iron ; Kidney Failure, Chronic ; Oxygen ; Plasma ; Reactive Oxygen Species ; Superoxide Dismutase* ; Superoxides* ; Uremia

Aging ; physiology ; Animals ; Catalase ; metabolism ; Circadian Rhythm ; Free Radicals ; metabolism ; Lipid Peroxides ; metabolism ; Male ; Melatonin ; metabolism ; Nitric Oxide ; metabolism ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism ; Thymus Hormones ; pharmacology

Preterm infants are vulnerable to the oxidative stress due to the production of large amounts of free radicals, antioxidant system insufficiency, and immature oligodendroglial cells. Reactive oxygen species (ROS) play a pivotal role in the development of periventricular leukomalacia. The three most common ROS are superoxide (O2*-), hydroxyl radical (OH*), and hydrogen peroxide (H2O2). Under normal physiological conditions, a balance is maintained between the production of ROS and the capacity of the antioxidant enzyme system. However, if this balance breaks down, ROS can exert toxic effects. Superoxide dismutase, glutathione peroxidase, and catalase are considered the classical antioxidant enzymes. A recently discovered antioxidant enzyme family, peroxiredoxin (Prdx), is also an important scavenger of free radicals. Prdx1 expression is induced at birth, whereas Prdx2 is constitutively expressed, and Prdx6 expression is consistent with the classical antioxidant enzymes. Several antioxidant substances have been studied as potential therapeutic agents; however, further preclinical and clinical studies are required before allowing clinical application.
Antioxidants ; Brain ; Brain Injuries ; Catalase ; Free Radicals ; Glutathione Peroxidase ; Humans ; Hydrogen Peroxide ; Hydroxyl Radical ; Infant, Newborn ; Infant, Premature ; Leukomalacia, Periventricular ; Oxidative Stress ; Parturition ; Peroxiredoxins ; Reactive Oxygen Species ; Superoxide Dismutase ; Superoxides

The superoxide anion, hydrogen peroxide, and hydroxyl radical are oxygen free radicals which arise in cell metabolism and which are toxic to cells, with an important role in carcinogenesis. The measurement of the oxygen free radical is a problem due to the instantaneously changing nature, and therefore the superoxide dismutase(SOD) is employed which act as an oxygen free radical scavenger. The authors quantitatively analyzed the SOD levels in normal uterine cervix epithelium, cervical intraepithelial neoplasia, and in invasive cervical cancer patients by the SOD-525R spectrophotometric assay and compared the results between each group with respect to prognostic variables such as stage of disease, cell type, lymph node involvement, and SCC Ag(TA-4 Ag) levels. The mean SOD levels were 0.41U/ml, 0.39U/ml and 0.73U/ml in the normal uterine cervix, intraepithelial neoplasia, and invasive cervical cancer groups, respectively, showing statistically significant difference by the Oneway anova test(p=0.05). The mean SOD levels according to the stage of disease were 0.5U/ml, 0.62U/ml, and 1. 15U/ml for stages I a, I b, and stage II and above(p=0.029). For the cell type the SOD levels were 0.77/ml for squamous cell carcinoma and 0.57U/ml for adenocarcinoma(p=0.15). For cancer cell lymph node involvement cases, the mean SOD levels were 0.75U/ml and 0.57U/ml for lymph node involvement and no involvement respectively(p=NS). The mean SOD levels also did not show any significance when compared with SCC Ag levels where SOD was 0.78U/ml for SCC Ag levels of more than 2.0ng/ml, and 0.77U/ml for SCC Ag levels of less than 2.0ng/ml. From the above results the authors conclude that SOD levels were higher in invasive cervical cancer tissues compared to intraepithelial neoplasia and normal cervical tissues, that SOD levels increased with higher stage of disease, and that there was no relationship between SOD levels and known prognostic variables such as cell type, lymph node involvement and SCC Ag level.
Carcinogenesis ; Carcinoma, Squamous Cell ; Cervical Intraepithelial Neoplasia ; Cervix Uteri ; Epithelium ; Female ; Free Radicals ; Humans ; Hydrogen Peroxide ; Hydroxyl Radical ; Lymph Nodes ; Metabolism ; Oxygen* ; Superoxides* ; Uterine Cervical Neoplasms

This study was designed to investigate the effects of pyroligneous liquor on oxygen radicals and their scavenger enzy-mes in the liver of Cri/Bgi CD rats (7 rats per group ). Male rats were fed a basic diet prepared in our Lab., PL-0 (Control ), PL-1, PL-25, PL-50 and PL-75 groups were prepared to be 0%, 1%, 25%, 50% and 75%with distilled water using pyrolig-neous liquor (35% of Choa Co. Ltd.), and were administrated orally for 8 weeks. Superoxide radical contents in liver mi-tochondria and microsomes were significantly decreased to 12-14%, 11-15%, respectively, in these PL-25 and PL-50 groups compared with the control group. Hydroxyl radical content in mitochondria and microsomes were markedly decreased to 12-20% and 17%, respectively, in these PL-25 and PL-50% groups compared with the control group. Hydro-gen peroxide content in mitochondria and microsomes were significantly decreased about 15-12% and 22-20% in liver of PL-25 and PL-50 groups compared with the control group. Mn-SOD and Cu/Zn-SOD activities in liver of PL-25 and PL-50 groups were remarkably increased to 15-25%, 11-16%, respectively, compared with the control group. GPx activities in mitochondria and microsomes were significantly increased in the liver of PL-25 and PL-50 groups compared with the control group. CAT activities in mitochondria and cytosol were significantly increased to 12-14%, 15-27%, respectively, in the liver of PL-25 and PL-50 groups compared with the control group. These results suggest that long term administra-tion orally of 25 and 50% pyroligneous liquor may effectively inhibit the formation of oxygen free radicals, and also scavenger enzyme activities significantly increase through the administration orally.
Animals ; Cats ; Cytosol ; Diet ; Free Radicals ; Humans ; Hydroxyl Radical ; Liver* ; Male ; Microsomes ; Mitochondria ; Oxygen* ; Rats* ; Reactive Oxygen Species* ; Superoxide Dismutase ; Superoxides ; Water

OBJECTIVETo investigate whether acute dipterex poisoning (ADP) may cause oxidative stress and free radical damage in the bodies of acute dipterex poisoning patients (ADPPs), and to explore the mechanisms by which ADP may cause oxidative stress and free radical damage.

METHODSFifty ADPPs and fifty healthy adult volunteers (HAVs) whose ages, gender and others were matched with the ADPPs were enrolled in a randomized controlled study, in which concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as concentration of lipoperoxide (LPO), and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and acetylcholinesterase (AChE) in erythrocytes were determined by spectrophotometric analytical methods.

RESULTSCompared with the average values of experimental parameters in the HAVs group, the average values of plasma NO and erythrocyte LPO in the ADPPs group were significantly increased (P<0.0001), while those of plasma VC, VE and beta-CAR as well as erythrocyte SOD, CAT, GPX and AChE in the ADPPs group were significantly decreased (P<0.0001). Bivariate correlation analysis and partial correlation analysis suggested that when NO and LPO values were increased, and VC, VE, beta-CAR, SOD, CAT and GPX values were decreased in the ADPPs, AChE value was decreased gradually in the ADPPs (P<0.001-0.0001). Reliability analysis of experimental parameters reflecting oxidative stress and free radical damage in the ADPPs showed that the reliability coefficient (8 items) alpha=0.6909, and the standardized item alpha=0.8574.

CONCLUSIONThe findings in the present study suggest that ADP can cause oxidative stress and free radical damage, and inhibit markedly erythrocyte acetylcholinesterase activity in ADPPs.

Acetylcholinesterase ; blood ; Adolescent ; Adult ; Ascorbic Acid ; blood ; Case-Control Studies ; Catalase ; blood ; China ; Cholinesterase Inhibitors ; poisoning ; Erythrocytes ; drug effects ; enzymology ; Female ; Free Radicals ; Glutathione Peroxidase ; blood ; Humans ; Insecticides ; poisoning ; Lipid Peroxides ; blood ; Male ; Nitric Oxide ; blood ; Oxidative Stress ; Poisoning ; blood ; Random Allocation ; Superoxide Dismutase ; blood ; Trichlorfon ; poisoning ; Vitamin E ; blood ; beta Carotene ; blood

Experimentally transient global cerebral ischemia using animal models have been thoroughly studied and numerous reports suggest the involvement of oxidative stress in the pathogenesis of neuronal death in ischemic lesions. In animal models, during the reperfusion period after ischemia, increased oxygen supply results in the overproduction of reactive oxygen species (ROS), which are involved in the process of cell death. ROS, such as superoxide anions, hydroxyl free radicals, hydrogen peroxide and nitric oxide are produced as a consequence of metabolic reactions and central nervous system activity. These reactive species are directly involved in the oxidative damage of cellular macromolecules such as nucleic acids, lipids and proteins in ischemic tissues, which can lead to cell death. Antioxidant enzymes are believed to be among the major mechanisms by which cells counteract the deleterious effect of ROS after cerebral ischemia. Consequently, antioxidant strategies have been long suggested as a therapy for experimental ischemic stroke; however, clinical trials have not yet been able to promote the translation of this concept into patient treatment regimens. This article focuses on the contribution of oxidative stress or antioxidants to the post-ischemic neuronal death following transient global cerebral ischemia by using a gerbil model.
Antioxidants ; Brain Ischemia* ; Cell Death ; Central Nervous System ; Free Radicals ; Gerbillinae* ; Humans ; Hydrogen Peroxide ; Ischemia ; Models, Animal ; Neurons ; Nitric Oxide ; Nucleic Acids ; Oxidative Stress ; Oxygen ; Reactive Oxygen Species ; Reperfusion ; Stroke ; Superoxides

The free radicals generated during the ischemic/reperfusion period have been suggested as a possible cause for tissue damage in organs. This state was conducted to investigate protective effects of free radical scavengers through changes in the lipid peroxide content of the testis when administered before reperfusion of testicular torsion. These protective agents include superoxide dismutase(SOD), an oxygen radical scavenger and dimethylthiourea(DMTU), a hydroxyl radical scavenger. Forty five Sprague-Dawley rats were divided into 9 groups, each containing 5 rats. Group 1 served to determine basal values of the lipid peroxide content of the testis ; group 2 underwent sham operation as a control ; group 3 was subjected to unilateral testicular torsion lasting 3 hours; group 4, 5 were subjected to the detorsion lasting 1 hour and 2 hours following torsion for 3 hours; group 6, 7, 8, 9 were treated with SOD or DMTU before detorsion following torsion lasting 3 hours. The measurement of thiobarbituric acid reactive products of lipid peroxidation(TBAR) were employed to assess the extent of lipid peroxidation in testicular tissues. TBAR from sham operation control groups did not differ significantly from basal groups (p>0.05). Testicular torsion caused a significant increase in TBAR in the testis (p<0.05) when compared with basal values and detorsion caused a further significant increase when compared with values obtained after torsion. But TBAR after 1 hr detorsion did not change significantly compared with values obtained after 2 hours detorsion. The pretreatment with SOD prevented this further increase but the pretreatment with DMTU didn't. In conclusion, biochemically, reperfusion injury occurs in testis following detorsion after testicular torsion of 720 lasting 3 hours. The pretreatment with SOD, an oxygen radical scavenger, is effective in preventing reperfusion injury.
Animals ; Free Radical Scavengers* ; Free Radicals ; Hydroxyl Radical ; Lipid Peroxidation ; Oxygen ; Protective Agents ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury* ; Reperfusion* ; Spermatic Cord Torsion* ; Superoxides ; Testis