Erythrocyte Superoxide Dismutase Levels Research Articles

Superoxide dismutase, glutathione peroxidase, and catalase antioxidant enzymes in chronic tobacco smokers and chewers: A case-control study.

Tobacco has a time dependent effect on the antioxidant system of the body. This study was designed to determine and compare alteration in levels of erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) in blood subgroups of tobacco smokers and chewers with controls. Blood samples were collected from 30 tobacco smokers (> 20 cigarettes daily), 30 tobacco chewers (> 10 packets gutka daily) and 30 controls. These groups were further divided into three subgroups (n=10) based on duration of habit (<5 yrs, 5-10 yrs, >10 yrs). The level of erythrocyte SOD, GPx and CAT were measured using standard procedures. The SOD and CAT levels were significantly decreased in all subgroups of smokers and chewers whereas GPx level was significantly increased. Positive correlation was observed between SOD, GPx and CAT levels with change in duration of habit in all subgroups. No significant difference observed in SOD and CAT activity between tobacco smokers and chewers. The findings suggested that antioxidative enzyme activities have significant correlation with change in the duration of tobacco use. Measurement of markers of free radical activity might be useful for estimating the level of oxidative stress caused by tobacco use.

The Role of Serial Oxidative Stress Levels in Acute Traumatic Brain Injury and as Predictors of Outcome

Oxidative stress is thought to participate in the pathobiology of secondary brain injury after acute traumatic brain injury (TBI). This study posits that oxidative stress levels in acute TBI are predictive of outcome. Two hundred and twenty-nine blood samples from 88 patients admitted within 24 hours after TBI were obtained on admission and on days 4 and 7. Serial plasma oxidative level and antioxidant were examined in 88 patients with acute TBI and 27 control individuals. Compared with controls, patients with TBI had significantly increased serum glutathione (GSH) levels on presentation and significantly decreased erythrocyte superoxide dismutase levels. Outcome was assessed on discharge using the Glasgow Outcome Scale. Serum GSH and erythrocyte superoxide dismutase levels were significantly higher in the good outcome group than in the poor outcome group on day 1 (P = 0.008 and P = 0.026, respectively). In the logistic regression analysis, only motor deficits and GSH levels on presentation were independently associated with outcome. A GSH cutoff value of 1.106 μmol/L on presentation was associated with good outcome in patients with acute TBI. Quantifying biomarkers of oxidative stress and antioxidant status of serum correlate with trauma severity and may be used to predict outcomes after TBI. Higher serum GSH levels on admission are associated with better outcome.

Irradiation Can Selectively Kill Tumor Cells while Preserving Erythrocyte Viability in a Co-Culture System

An understanding of how to safely apply intraoperative blood salvage (IBS) in cancer surgery has not yet been obtained. Here, we investigated the optimal dose of 137Cs gamma-ray irradiation for killing human hepatocarcinoma (HepG2), gastrocarcinoma (SGC7901), and colonic carcinoma (SW620) tumor cells while preserving co-cultured erythrocytes obtained from 14 healthy adult volunteers. HepG2, SGC7901, or SW620 cells were mixed into the aliquots of erythrocytes. After the mixed cells were treated with 137Cs gamma-ray irradiation (30, 50, and 100 Gy), tumor cells and erythrocytes were separated by density gradient centrifugation in Percoll with a density of 1.063 g/ml. The viability, clonogenicity, DNA synthesis, tumorigenicity, and apoptosis of the tumor cells were determined by MTT assay, plate colony formation, 5-ethynyl-2'-deoxyuridine (EdU) incorporation, subcutaneous xenograft implantation into immunocompromised mice, and annexin V/7-AAD staining, respectively. The ATP concentration, 2,3-DPG level, free Hb concentration, osmotic fragility, membrane phosphatidylserine externalization, blood gas variables, reactive oxygen species levels, and superoxide dismutase levels in erythrocytes were analyzed. We found that 137Cs gamma-ray irradiation at 50 Gy effectively inhibited the viability, proliferation, and tumorigenicity of HepG2, SGC7901, and SW620 cells without markedly damaging the oxygen-carrying ability or membrane integrity or increasing the oxidative stress of erythrocytes in vitro. These results demonstrated that 50 Gy irradiation in a standard 137Cs blood irradiator might be a safe and effective method of inactivating HepG2, SGC7901, and SW620 cells mixed with erythrocytes, which might help to safely allow IBS in cancer surgery.

Plasma Malondialdehyde, Thyroid Hormones and Some Blood Profiles in Ovine Babesiosis

Thyroid hormone and plasma malondialdehyde (MDA) levels as well as other blood parameters were performed in ovine babesiosis. The Babesia genus comprises pathogen parasites that cause economic problems in livestock management. Many published studies have suggested its complications, but few studies have assessed blood biochemistry. Hence, a survey of the changes in blood parameters in animals with babesiosis may be useful. Sheep with acute babesiosis were identified based on clinical signs and the observation of Piroplasms in red blood cells with Giemsa staining of blood smears. Blood samples were obtained from the jugular veins of 46 babesiosisinfected sheep and 46 healthy sheep without babesiosis. Malondialdehyde (MDA), Paraoxonase (PON), low density lipoprotein (LDL), high density lipoprotein (HDL), Cholestrol (Chol), Total plasma protein (TPP) and glucose (GL) in plasma and triiodothyronine (T3), thyroxine (T4) measured in serum. Levels of erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and total antioxidant capacity (TAC) were also measured. The results indicated significant increases (P<0.01) in MDA and GL and significant decreases (P<0.01) in the levels of antioxidant enzymes (PON, GSH-Px, CAT, TAC [except SOD], TPP, T3, andT4, LDL, HDL, and Chol levels when compared with healthy group. The results suggested that hypothyroidism with concurrent oxidative stress are significant signs of ovine babesiosis.

Effect of Gymnema sylvestre R. Br. leaves extract on certain physiological parameters of diabetic rats

Gymnema sylvestre R. Br. (G. sylvestre) belonging to the family Asclepiadaceae, has been used as a traditional medicine plant in Africa, Australia and Asia especially in India. Aim of the studyThe present study aimed to clarify the effect of G. sylvestre leaves extract on several physiological parameters of diabetic rats. Materials and methodsG. sylvestre leaves extract (18mg/kg body weight) was orally administered for 30days to normal and streptozotocin (STZ) diabetic rats. ResultsSTZ-diabetic rats exhibited a significant increase in plasma glucose, liver function enzymes [alanine aminotransaminase (ALT) and aspartate aminotransaminase (AST)], triglycerides, total cholesterol, LDL-cholesterol malondialdehyde, catalase, reduced glutathione and a significant decrease in insulin, HDL-cholesterol and erythrocyte superoxide dismutase levels. Treatment diabetic rats with G. sylvestre leaves extract significantly decreased plasma glucose, ALT, AST, triglycerides, total cholesterol, LDL-cholesterol, malondialdehyde and significantly increased insulin, HDL-cholesterol and erythrocyte superoxide dismutase levels compared to untreated diabetic rats. ConclusionIt could be concluded that G. sylvestre leaves extract treated diabetic rats’ complications including hyperglycemia, hypoinsulinemia, hyperlipidemia and oxidative stress.

The influence of vitamin E supplementation on erythropoietin responsiveness in chronic hemodialysis patients with low levels of erythrocyte superoxide dismutase

About 12-15 % of hemodialysis patients have a poor response to recombinant human erythropoietin (rHuEPO). The aim of this prospective study was to examine the influence of oxidative stress and vitamin E supplementation on rHuEPO responsiveness in chronic hemodialysis patients. Sixty-five hemodialysis patients treated with rHuEPO were studied. Those with iron deficiency, blood loss, malignancy, vitamin B12 and folate deficiency, severe hyperparathyroidism, liver cirrhosis, and congestive heart failure were excluded. Twenty-one healthy volunteers served as a control group. Malondialdehyde, carbonyl proteins, erythrocyte superoxide dismutase (SOD), ceruloplasmin, and serum antioxidant capacity were measured. Values of SOD > 150 U/ml were considered as normal. Patients with SOD < 150 U/ml were divided in two groups: group A (n = 11): treated with vitamin E 400 mg/day (600 IU/day) for 8 weeks; group B (n = 13): not treated. A third, group C consisted of patients with normal SOD. rHuEPO doses (U/kg/week) were recorded. rHuEPO responsiveness index was calculated as rHuEPO U/week/hematocrit. A poor response was defined as a rHuEPO responsiveness index >200. SOD positively correlated with hemoglobin (p = 0.0018, R = 0.337) and negatively with rHuEPO responsiveness index (p = 0.0122, R = 0.319). Vitamin E-treated patients from group A exhibited significantly increased hemoglobin levels as compared to initial values (10.5 ± 0.3 vs. 8.6±0.4, p = 0.002). In comparison with group B, the vitamin E-treated patients displayed a higher hemoglobin (10.5 ± 0.3 vs. 9.4 ± 0.3, p = 0.04), had a lower rHuEPO dose (85.7 ± 7.4 vs. 136.8 ± 13.8, p = 0.025), and a significantly improved rHuEPO responsiveness (rHuEPO responsiveness index 177.9 ± 28.6 vs. 314.1 ± 34.0, p = 0.006). Patients from group A significantly improved their rHuEPO responsiveness after vitamin E therapy as compared to baseline (rHuEPO responsiveness index 177.9 ± 28.6 vs. 271.7 ± 30.3, p = 0.034). We conclude that lower values of SOD correlate with lower hemoglobin, higher rHuEPO dose and poor response to rHuEPO in chronic hemodialysis patients. Vitamin E supplementation significantly improves rHuEPO responsiveness, increases hemoglobin level, and decreases rHuEPO dose.

Influence of Dietary Red Palm Oil on Antioxidant Status in Male Wistar Rats

Antioxidant status in male rats following the dietary consumption of red palm oil (RPO) was investigated. Male wistar rats were randomly divided into three groups. Group 1 (n=5) received no RPO supplementation and served as the control while group 2 (n=6) and 3 (n=6) received 2ml and 4ml RPO respectively. Plasma total polyphenols, plasma antioxidant capacity i.e. oxygen radical absorbance capacity (ORAC), ferric reducing antioxidant power (FRAP) as well as liver and erythrocyte antioxidant enzymes [catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD)] levels were determined using established techniques. Our results showed no significant differences (p&lt;0.05) in total polyphenols, ORAC and FRAP in palm oil fed groups when compared with the control group. Catalase levels significantly increased (p&lt;0.05) at both 2ml and 4ml RPO in the liver and erythrocyte. There was no significant difference in the liver GPx levels in palm oil fed groups while erythrocyte GPx level significantly increased at 4ml RPO when compared with the control group. Red palm oil did not significantly increase (p&lt;0.05) liver and erythrocyte SOD levels in all the groups when compared with the control group. In conclusion, red palm oil increased the levels of liver and erythrocyte catalase as well as erythrocyte glutathione peroxidase level and hence, its dietary consumption could help to boost antioxidant status in the body and thus promote good health.Source of Research Support‐ University Research Funding provided by Cape Peninsula University of Technology, Bellville, South Africa

Levotiroksin Tedavisi Gören Hashimoto Tiroiditi Hastalarında Serum Total Antioksidan Kapasitesi, Lipit Profili, Malondialdehit ve Eritrosit Süperoksit Dismutaz Düzeyleri

Objective: To compare the serum level of total antioxidant status (TAS), malondialdehyde (MDA) and erythrocyte superoxide dismutase (SOD) levels in Hashimoto thyroiditis patients treated with levothyroxine and healthy control subjects and to assess possible correlations of these parameters with biochemical parameters such as glucose and lipid profile. Material and Methods: SOD, TAS, MDA, fasting glucose, lipid profile, thyroid hormones and body mass index (BMI) were measured in 30 Hashimoto thyroiditis patients treated with levothyroxine and 30 healthy control subjects. Results: Body Mass Index was increased in Hashimoto thyroiditis patients compared to control subjects. The biochemical parameters such as glucose, triglycerides, total cholesterol and low-density lipoprotein cholesterol (LDL-C) were higher and high-density lipoprotein cholesterol (HDL-C) was lower in the patient group than in control patients. TAS and MDA levels were significantly higher and erythrocyte SOD levels were lower in the patient group compared to the control group. Conclusion: Our study showed that lipid peroxidation was increased in hypothyroid patients compared to healthy controls, even though they were treated with levothyroxine. Erytrocyte SOD levels were lower and TAS was higher in the patient group compared to the control group. Thyroiditis patients treated with levothyroxine had normal thyroid homone ranges but treatment did not seem to improve dyslipidemia and oxidative stres. In conclusion, although the hypothyroid patients had normal thyroid hormone levels due to levothyroxine treatment, oxidative stress parameters seemed to contiue to increase. Thus, we suggest that antioxidant treatment may be continued even after the achievement of euthyroidism.

EFFECT OF ZOBO DRINK (HIBISCUS SABDARIFFA WATER EXTRACT) ON BIOCHEMICAL AND HEMATOLOGICAL PARAMETERS IN MALE CYCLISTS

The aim of the present study was to evaluate, in a group of male cyclists the effects of short-term consumption of aqueous extract of the dried calyx of Hibiscus sabdariffa (popularly referred to as zobo in Nigeria) on some hematological and biochemical indices. Mmale clyclists who consumed the placebo (test control group) had significantly reduced hemoglobin (Hb) concentration, packed cell volume (PCV) and red blood cell (RBC) count, while the white blood cell (WBC) was signifi- cantly increased relative to inactive control subjects after one and two months of study. These pa- rameters were restored to a level comparable to controls in the group of cylists who consumed zobo drink (test group) for one and two months. The levels of erythrocyte superoxide dismutase (SOD), catalase (CAT) and lipid peroxidation (LPO) were significantly elevated in cyclists in the test control group relative sedentary controls after both durations of the study. These parameters were restored toward control values after two months of ingestion of zobo drink. The lactate dehy- drogenase activity in the erythrocyte of the cyclist was significantly high with or without zobo in- gestion relative to control after both durations of the study. In conclusion, the results obtained indi- cate that consumption of zobo drink (which is rich in antioxidants and other components) may be beneficial to athletes as it restored the exercise induced alterations of some hematological and bio- chemical parameters in cyclists under regular training.

The effect of 1α,25(OH) 2D 3 vitamin over oxidative stress and biochemical parameters in rats where Type 1 diabetes is formed by streptozotocin

Introduction The 1α,25-dihydroxyvitamin D 3 [1α,25(OH) 2D 3] plays an essential role in mineral balance but has also been recognized as a powerful modulator of immune response. We aimed to examine the effect of the 1α,25(OH) 2D 3 treatment on insulin/c-peptide, catalase, superoxide dismutase (SOD), and blood glucose in rats that take streptozotocin (STZ). Methods Forty pieces of male rats of Albino family whose average weights were 261.00±07.62 g were used in the study. Rats were made diabetic by giving STZ of 40 mg/kg during 5 days through intraperitoneal path. Some of the diabetic group and nondiabetic group were received 1α,25(OH) 2D 3. The levels of SOD, insulin, c-peptide, glucose, SOD, and catalase were measured at the zero, second, fourth, and sixth weeks. Results Erythrocyte SOD levels didn't show a significant difference at the end of the sixth week in all groups when compared to the beginning. While erythrocyte catalase levels didn't show a significant difference in nondiabetic control and nondiabetic with vitamin D, and diabetic with vitamin D groups at the end of sixth week when compared to the beginning, a significant measurement was made in diabetic without vitamin D group. Maximal insulinitis scoring values were observed in diabetic without vitamin D that didn't receive 1α,25(OH) 2D 3 treatment. Conclusion The highness of insulin and c-peptide levels in the group that received treatment when compared to other groups and the lowness of oxidative markers such as SOD, catalase in this study can be explained by the fact that 1α,25(OH) 2D 3 treatment prevents the intervention of apoptosis mechanism.

The effect of different treatment modalities on oxidative stress in COPD

Oxidant/antioxidant interactions are known to be important processes in the pathogenesis of chronic obstructive pulmonary disease (COPD). We aimed to evaluate the effects of corticosteroids (CS), and N-acetylcysteine (NAC) on plasma oxidant/antioxidant levels in patients with COPD. This study utilised a single-blind, randomised, placebo-controlled, parallel-group methodology. We enrolled 58 patients with stable COPD and 30 healthy controls with similar demographic profiles. The patients with COPD were randomly divided into three treatment groups. Group 1 received basal treatment (regular ipratropium bromide and beta-2 agonist as needed), placebo CS and placebo NAC. In addition to basal treatment, group 2 received oral CS (methylprednisolone 40 mg/day) and placebo NAC. Group 3 received basal treatment plus NAC (600 mg/day) and placebo CS. Each group received treatment for 15 days. We measured plasma malondialdehyde (MDA) and superoxide dismutase (SOD) at the start and the end of study. Post-treatment plasma MDA levels were significantly lowered only in group 2 (P=0.004). No significant differences were found with respect to erythrocyte SOD levels. This study demonstrates that oral CS, by aiding the oxidant/antioxidant system, may offer a new therapeutic option in COPD treatment.

Sister chromatid exchange analysis in patients with psoriasis

Psoriasis is a common, chronic inflammatory skin disease with unknown aetiology. An increased reactive oxygen species (ROS) and insufficient antioxidant activity have been determined in psoriatic lesions. The analysis of sister chromatid exchange (SCE) is a cytogenetic technique used to show DNA damage caused by an exchange of DNA fragments between sister chromatids. The study aimed to determine the rates of SCE in psoriatic patients (17 female and 19 male) and healthy controls (15 female and 15 male) as well as superoxide dismutase (SOD), glutathione peroxidase (GP) and catalase (CAT) activity in both groups. We found significantly higher SCE rates in the patients (P < 0.00001). In addition, statistically significant decreased levels of erythrocyte SOD and CAT activities were noted in the patients(P < 0.001 and P < 0.05 respectively). Furthermore, a statistically significant increased erythrocyte GP activity was found in the psoriasis group (P < 0.05). Our results indicate that chromosomal instability may play an important part in the aetiology of psoriasis. In addition, the results support the hypothesis of an imbalance in the oxidant-antioxidant system in psoriasis.

Oxidative stress parameters in patients with slow coronary flow

We investigated the probable role of free-radical damage in the pathogenesis of slow coronary flow (SCF) by using oxidative stress parameters. Sixty-four patients with angiographically proven SCF and 63 patients with normal coronary flow (NCF) pattern with similar risk profiles were enrolled in this study. We measured erythrocyte superoxide dismutase (SOD), reduced glutathione (GSH), serum malondialdehyde (MDA), catalase and myeloperoxidase (MPO) levels in all subjects. There were statistically significant differences in the levels of erythrocyte SOD, GSH and serum MDA between the 2 groups. Serum MDA (P = 0.003) and erythrocyte SOD levels (P = 0.0001) were increased in the SCF group. The level of erythrocyte GSH (P = 0.010) was lower in patients with SCF. There were no differences between the groups' serum catalase (P = 0.682) and MPO levels (P = 0.070). Our data showed that in patients with SCF, serum MDA and erythrocyte SOD levels were increased while erythrocyte GSH levels were decreased significantly, compared with NCF patients. These results indicate that free-radical damage may play a role in the pathogenesis of SCF.

Elevated F 2-isoprostanes in thalassemic patients

This study was aimed at investigating oxidative stress in thalassemic patients by measurement of the oxidative damage biomarker, F 2-isoprostanes (F 2-IsoPs), using gas chromatography-mass spectrometry. The results showed that the mean value of urinary F 2-IsoPs, normalized with creatinine, in the thalassemic group was significantly higher than that from healthy subjects (3.38 ± 2.15 ng/mg creatinine vs 0.86 ± 0.55 ng/mg creatinine, respectively), and the mean value of plasma total F 2-IsoPs in the thalassemic group was also significantly higher than that from healthy subjects (0.39 ± 0.15 ng/ml vs 0.18 ± 0.03 ng/ml, respectively). Serum ferritin, erythrocyte superoxide dismutase (SOD), glutathione peroxidase, glutathione, and TBARS levels after treatment of erythrocytes with H 2O 2 were also investigated, and serum ferritin and erythrocyte SOD levels were significantly higher in thalassemic patients. Our findings are consistent with oxidative stress in thalassemia patients.

Oxidative stress in term small for gestational age neonates born to undernourished mothers: a case control study.

BackgroundThe objective of this study was to assess the status of oxidative stress in term small for gestational age (SGA) newborn infants born to undernourished mothers by estimating levels of erythrocyte superoxide dismutase (SOD), catalase, reduced glutathione, and serum malondialdehyde (MDA) in cord blood and comparing them to healthy appropriate for gestational age (AGA) controls. This was done in a case control design at a tertiary level teaching hospital.MethodsWe included 20 singleton healthy SGA newborn infants born between 38–40 weeks to undernourished mothers with a) post-pregnancy weight < 50 kg or height < 145 cm AND b) hemoglobin < 8.0 g/dL or serum albumin < 2.5 g/dL. An equal number of age and sex matched AGA newborn infants born to healthy mothers served as Controls. Mothers with other risk factors and newborns with complications during delivery or immediate newborn period were excluded. MDA, SOD, catalase and reduced glutathione were measured in the cord blood of all neonates and compared between the groups (unpaired t test); levels were also correlated to maternal weight, height, hemoglobin, and albumin by both univariate (pearsonian correlation) and multivariate (multiple regression) analysis.ResultsThe activity of MDA was increased (5.33 ± 0.72 vs 2.55 ± 0.22 nmol/mL; P < 0.0001) while levels of superoxide dismutase (493.6 ± 54.9 vs. 786.8 ± 79.1 U/g Hb; P < 0.0001), catalase (1.48 ± 0.24 vs. 2.31 ± 0.20 U/g Hb; P < 0.0001) and reduced glutathione (2.84 ± 0.37 vs 6.42 ± 0.23 Umol/g Hb, P < 0.0001) were decreased in term SGA born to undernourished mothers as compared to term AGA born to healthy mothers. On univariate analysis, all the markers of oxidative stress correlated significantly with maternal parameters (P < 0.005). On multivariate analysis, maternal albumin and hemoglobin accounted for maximum correlation with the markers of oxidative stress.ConclusionsIntrauterine malnutrition is associated with significant oxidative stress in small for gestational age neonates born at term to malnourished mothers.

Effects of raloxifene on serum malondialdehyde, erythrocyte superoxide dismutase, and erythrocyte glutathione peroxidase levels in healthy postmenopausal women

Objective: To investigate the relationship between raloxifene administration and serum malondialdehyde (MDA), erythrocyte superoxide dismutase (SOD), erythrocyte glutathione peroxidase (GPx) levels in healthy postmenopausal women. Methods: In a randomized and placebo-controlled design, 80 women received either 60 mg/day raloxifene or placebo for 24 weeks. MDA, SOD, and GPx levels were assessed at 0,4,12, and 24 weeks. Wilcoxon signed-rank test and Mann-Whitney U test were used for comparisons. Results: Six women in the treatment arm and eight women in the placebo group discontinued the study. Mean serum MDA levels were significantly (p = 0.001) decreased from 11.4 nmol/ml at baseline to 8.9 nmol/ml at week 12 with raloxifene treatment. Mean erythrocyte SOD activity was significantly (p = 0.02) reduced from 1472 U/g Hb at baseline to 1173 U/g Hb at week 12 following raloxifene administration. Lowered serum MDA and erythrocyte SOD levels persisted during treatment. On contrary, erythrocyte GPx levels did not change significantly with raloxifene administration. Conclusions: Raloxifene (60 mg/day) lowers serum MDA levels and erythrocyte SOD activity in postmenopausal women after 12 weeks of treatment. The clinical implications of these findings need to be determined.

Effects of prostaglandin E1, melatonin, and oxytetracycline on lipid peroxidation, antioxidant defense system, paraoxonase (PON1) activities, and homocysteine levels in an animal model of spinal cord injury.

Investigation of the effects of prostaglandin E1, melatonin, and oxytetracycline on lipid peroxidation, antioxidant and paraoxonase activities, and homocysteine levels in an experimental model of spinal cord injury. To determine the antioxidant efficacy of prostaglandin E1, melatonin, and oxytetracycline and whether paraoxonase and homocysteine can be used as monitoring parameters in the acute oxidative stress of spinal cord injury. Melatonin has been found useful in spinal cord injury in previous studies. No study exists investigating the effects of melatonin, prostaglandin E1, and oxytetracycline as well as the response type of paraoxonase enzyme and homocysteine levels in the acute oxidative stress of spinal cord injury. Sixty-three male albino Wistar rats were anesthetized with 400 mg/kg chloral hydrate and divided into 5 groups. The G1 (n = 7) control group provided the baseline levels. G2-G5 underwent T3-T6 total laminectomies and spinal cord injuries by clip compression at the T4-T5 levels. Medications were applied to G3-G5 right after clip compression. Hence, G2 constituted laminectomy + injury, G3 laminectomy + injury + prostaglandin E1; G4 laminectomy + injury + melatonin, and G5 laminectomy + injury + oxytetracycline groups. Animals were decapitated either the first or fourth hour after injury. Spinal cord tissue and blood malonyldialdehyde and plasma homocysteine levels, plasma glutathione peroxidase, superoxide dismutase, paraoxonase activities were assayed. The SPSS 9.0 program was used for statistical analysis and graphics. Intergroup comparisons were made by Bonferroni corrected Mann Whitney U test (P < 0.025) and intragroups comparisons by Wilcoxon Rank test (P < 0.03). In injury groups, plasma homocysteine levels decreased and paraoxonase activities increased as erythrocyte superoxide dismutase levels and plasma glutathione peroxidase activities decreased in parallel to increases of tissue and blood malonyldialdehyde levels. These alterations were relatively suppressed by prostaglandin E1, melatonin, and oxytetracycline administrations in varying degrees. Melatonin was the most powerful agent, particularly at the fourth hour. Oxytetracycline was also effective, both at the first and fourth hour. Prostaglandin E1 was effective in comparison to injury group, but not as much as melatonin and oxytetracycline. Melatonin and oxytetracycline are effective in preventing lipid peroxidation in spinal cord injury. Paraoxonase and homocysteine can be used in monitoring the antioxidant defense system as well as superoxide dismutase and plasma glutathione peroxidase, both in injury and medicated groups.

Lipid peroxidation and antioxidant defence system in patients with active or inactive Behçet's disease.

To evaluate plasma lipid peroxidation and enzymatic and non-enzymatic antioxidant systems in patients with Behçet's disease, plasma malondialdehyde levels and total antioxidant status, erythrocyte superoxide dismutase and whole blood glutathione peroxidase activities were studied in 15 patients with active disease and in 30 with inactive disease, and compared with 20 age-matched healthy control subjects. Plasma malondialdehyde levels were significantly higher in patients with active Behçet's disease than in patients with inactive disease, who had significantly higher levels than control subjects. The plasma total antioxidant status of both groups of patients was significantly lower than that of controls. Furthermore, whole blood glutathione peroxidase activity was significantly lower in patients with active versus inactive Behçet's disease. There were no significant differences in erythrocyte superoxide dismutase levels between the groups. In conclusion, there is an increase in oxidative stress in Behçet's disease. Despite this stress, the antioxidant system is deficient and inadequate, especially in patients who are in an active phase of the disease.

The role of oxidants and antioxidants in generalized vitiligo.

Oxidative stress may be induced by increasing the generation of reactive oxygen species (ROS) and other free radicals. The generation of ROS is known to be associated with a decrease in antioxidant levels. In the present study, the role of oxidative stress was assessed in the pathogenesis of generalized vitiligo. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione (GSH) levels in erythrocytes and serum malondialdehyde (MDA) and nitric oxide (NO) levels were investigated in 24 patients with generalized vitiligo and 20 healthy controls. Our results indicated that significantly increased levels of erythrocyte SOD, serum MDA, and NO were associated with a marked reduction of erythrocyte GSH-Px and GSH activities in patients with generalized vitiligo (p<0.05). Our observations suggest that the presence of an imbalance in the oxidant-antioxidant system might play a role in the pathogenesis of vitiligo. Our results further support the concept that free radical-mediated damage may be the initial pathogenic event in melanocyte degeneration in generalized vitiligo.

The role of oxidants and antioxidants in psoriasis.

Psoriasis vulgaris is a chronic inflammatory skin disease characterized by well-demarcated erythema and scaly plaques. The pathogenesis of psoriasis still remains unclear. An increased reactive oxygen species (ROS) and insufficient antioxidant activity have been determined in psoriatic lesions. To evaluate and compare superoxide dismutase (SOD) and glutathione peroxidase (GP) activity in erythrocytes, catalase (CAT) activityand malondialdehyde (MDA) levels in serum of subjects with psoriasis and controls as well as MDA levels in skin biopsies from both groups. Twenty-two psoriatic patients (12 women and ten men) and 22 (12 women and ten men) healthy controls were involved in this study. Statistically significant decreased levels of erythrocyte SOD and GP activities were noted in psoriatic subjects. Furthermore, a statistically significant increased serum CAT activity was found in the psoriasis group. No statistically significant difference was found in the serum MDA levels in the two groups, however, statistically significant increased tissue levels of MDA were noted in the psoriasis group. Our results support the hypothesis of an imbalance in the oxidant-antioxidant system in psoriasis.