Effect of erythropoietin on membrane lipid peroxidation, superoxide dismutase, catalase, and glutathione peroxidase of rat RBC

Starved animals having low levels of erythropoietin in blood showed increased MDA, fluorescent pigments, and met-Hb values whereas the hemoglobin concentration decreased significantly on starvation. In vivo and in vitro studies with Ep reversed the effects of starvation and brought these values close to normal. The activities of the enzymes (SOD, catalase, GSH-PX, GR G6PD, and 6PGD) which protect the RBC membrane directly or indirectly from peroxidative threat, decreased on starvation and restored to normal levels after Ep treatment.     

Glutathione-S-transferase, superoxide dismutase, xanthine oxidase, catalase, glutathione peroxidase and lipid peroxidation in the liver of exercised rats

Glutathione-S-transferase (GST), superoxide dismutase (SOD), Xanthine oxidase, selenium-dependent glutathione peroxidase (GPxI), catalase activities and malondialdehyde (MDA) content were determined in liver of three groups of exercised rats (E) viz., one day (E1), 10 days (E10) and 60 days (E60). GST, SOD and xanthine oxidase activities increased significantly with the increase in exercise period. Lipid peroxidation, expressed in terms of MDA formation, also increased in the liver of all the three groups. But catalase activity decreased significantly during exercise. Further, GPxI did not show any significant change in its activity in response to exercise. Our findings indicate that: 1) The significant increase in GST activity suggests their induction aimed at counteracting the oxidant stress induced during exercise; 2) The significant increase in xanthine oxidase and SOD activities indicates the generation of more superoxide anion radicals and their removal, respectively. 3) The significant reduction in catalase activity denotes the decreased formation of hydrogenperoxides during exercise; and 4) The pattern of changes in the activity level of GPxI indicate its least participation during exercise. However, in another way it is giving a scope for the involvement of GPxII associated with GST in the reduction of organic hydroperoxides. Further more, the relative increase in MDA is considered as the indicator of the rate of lipid peroxidation in the wake of exhaustive exercise.     

CuZn superoxide dismutase, Mn superoxide dismutase, catalase and glutathione peroxidase in glutathione-deficient human fibroblasts

The effect of genetically determined glutathione deficiency on the fibroblast content of CuZn superoxide dismutase, Mn superoxide dismutase, catalase and glutathione peroxidase was investigated. No significant differences between glutathione-deficient and -proficient human fibroblasts were revealed. There was a large variation in the content of the investigated enzymes in fibroblasts grown and analysed on different occasions. Whereas the contents of CuZn superoxide dismutase, catalase and glutathione peroxidase did not deviate much from what has been found in other human cell-lines and tissues, the fibroblasts were found to contain exceptional amounts of Mn superoxide dismutase.     

Activity of glutathione peroxidase, superoxide dismutase and catalase and lipid peroxidation intensity in stallion semen during storage at 5 degrees C

Sperm cell membranes are susceptible to peroxidative damage by an excess of reactive oxygen species (ROS). Antioxidative defence systems consisting of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) physiologically control the balance between ROS production and neutralization. In the present study the hypothesis was tested that lipid peroxidation occurs during storage of semen at 5 degrees C and that semen extender has positive effects on the antioxidative potential of equine semen. The aim of the study was to determine the activity of GSH-Px, SOD and CAT and the concentration of thiobarbituric acid reactive substances (TBARS) as an indicator of lipid peroxidation in native semen and after addition of extender, cooling and storage. Semen was collected from fertile Shetland stallions. In experiment 1, activity of antioxidative enzymes was determined immediately after semen collection and after 24 h storage at 5 degrees C. Enzyme activities were measured in native semen, semen diluted with semen extender, spermatozoa resuspended after centrifugation in extender and 0.9% NaCl as well as in undiluted and extender-diluted seminal plasma. In experiment 2, TBARS concentrations were analysed during storage of semen at 5 degrees C for 24 h. Semen storage for 24 h at 5 degrees C did not change activity of the examined enzymes. Antioxidative activity was significantly higher in extended than in native semen as well as in extended plasma than in undiluted plasma. In conclusion, the addition of semen extender increases the antioxidative activity in seminal plasma of stallions. Basal antioxidative activity in native semen as well as increased activity in extended semen are maintained over 24 h storage at 5 degrees C. TBARS content did not increase during semen storage. In conclusion, lipid peroxidation does not increase substantially during semen storage. The enzymatic antioxidative activity in semen apparently prevents ROS formation and is further increased by addition of semen extender.     

A trifunctional enzyme with glutathione S-transferase, glutathione peroxidase and superoxide dismutase activity

Superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione S-transferase (GST) and glutathione reductase (GR) play crucial roles in balancing the production and decomposition of reactive oxygen species (ROS) in living organisms. These enzymes act cooperatively and synergistically to scavenge ROS, as not one of them can singlehandedly clear all forms of ROS. In order to imitate the synergy of the enzymes, we designed and generated a recombinant protein, which comprises of a Schistosoma japonicum GST (SjGST) and a bifunctional 35-mer peptide with SOD and GPX activities. The engineered protein demonstrated SOD, GPX and GST activities simultaneously. This trifunctional enzyme with SOD, GPX and GST activities is expected to be the best ROS scavenger.     

Automated assays for superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase activity

Automated assays for catalase, glutathione peroxidase, glutathione reductase, and superoxide dismutase are presented. The assay for catalase is based on the peroxidatic activity of the enzyme. The glutathione peroxidase and reductase assays measure the consumption of NADPH following the reduction of t-butyl hydroperoxide and oxidized glutathione, respectively. The assay for superoxide dismutase is based on the reduction of cytochrome c. All assays utilize the Cobas FARA clinical automated analyzer and provide considerable time savings over the manual assays.     

Biological variability of superoxide dismutase and glutathione peroxidase in blood

The enzymatic antioxidant defences of mammalian cells include copper-zinc superoxide dismutase (SOD)(Cu Zn-SOD; EC 1.15.1.1) which catalyses the dismutation of superoxide anions (O₂^.-) to hydrogen peroxide(H², O²)and a seleno-dependent glutathione peroxidase (GSH-px) (GSH-px; EC 1.11.1.9) which catalyses the degradation of H²O² to H²O and O². The measurement of these enzyme activities is often used as a possible biological index of oxidative stress in various clinical conditions. Complete understanding of such information requires knowledge of the random biological fluctuation of the enzyme activity which occurs in each individual. In the present investigation we examined this normal variability in 12 healthy volunteers (four women and eight men) aged 23–45 years, over 6 months. The intra-individual coefficients of variation (estimated using analysis of variance techniques) were 15% (SOD) and 13% (GSH-px). The analytical goal for imprecision was achieved for both enzymes, i.e. it was less than one half of the measured intra-individual variation. Both enzymes showed marked individuality, indicating that an individual's reference values are more useful than population-based data. The critical difference required for significant changes in serial results is 45% for SOD and 40% for GSH-px.     

Superoxide dismutase, glutathione peroxidase, catalase, and lipid peroxidation in the major organs of the aging rats

Glutathione peroxidase (GSh-Px), superoxide dismutase (SOD), catalase (CAT) activities and malon-dialdehyde (MDA) content were determined in heart, liver, kidney and brain of rats. Two different age groups (4 months; 24 months) were considered. GSH-Px and SOD activities decrease significantly for the aged liver and kidney. During aging, the activity of catalase increase in cardiac muscle and, in contrast, decrease in other organs. Lipids peroxidation, expressed in term of MDA formation, decrease in all the organs of the aged rats. The results indicate that: 1) the liver and kidney antioxidative defense decrease with age; 2) the enzymatic activities evolve in a different manner for different enzymes and organs. Furthermore, the results suggest that there is not any correlation between the SOD, CAT, and GSH-Px activities and the peroxidative status of the organs; thus, the age-related increase in the MDA content proposed as a criterion of aging process should be considered with caution.     

Determination of glutation peroxidase and superoxide dismutase activities in canine seminal plasma and its relation with sperm quality and lipid peroxidation post thaw

Lipid peroxidation (LPO) of dog spermatozoa was assessed in fresh semen and in samples of the same ejaculates after freezing and thawing. Particular attention was paid to individual differences in the susceptibility to LPO and its possible relationship with freezeability. Innate levels of LPO were low in fresh spermatozoa but increased after thawing in one of the dogs included in our study. The level of lipid peroxidation in fresh spermatozoa was not correlated with that of thawed spermatozoa. Negative correlations were detected between the activity in seminal plasma of GPx and sperm velocities post thaw (P < 0.01), however SOD activity was positively correlated with the percentage of linear motile sperm post thaw (P < 0.05).     

Relationship between total superoxide dismutase activity with lipid peroxidation, dynamics and morphological parameters in canine semen

There is a lack of information regarding biochemical studies on canine semen. The knowledge of canine sperm metabolism is important because this species has differences in fertility among males, but biochemical studies are not well developed in this species. Reactive oxygen species (ROS) are active molecules produced during the oxygen reduction that have been implicated in several deleterious effects on the function and viability of spermatozoa when they are produced at high concentrations. Peroxidation of the plasma membrane phospholipids leads to a loss of motility, viability, and cytosolic elements, metabolic changes and structural alterations in spermatozoa. The most important antioxidant enzyme involved in ROS detoxification in mammalian spermatozoa is superoxide dismutase (SOD). The aims of the present study were to determine the presence of SOD-like activity in different fractions of canine semen, and to determine the relationship between SOD-like activity and different morphological, dynamical and biochemical parameters in canine spermatozoa. We demonstrated the presence of SOD-like activity in canine seminal plasma and spermatozoa; the negative correlation between SOD-like activity and lipid peroxidation concentrations in spermatozoa suggests a protective effect of this enzymatic activity against the potential oxidative stress in canine spermatozoa. A significant negative correlation between percentage of abnormal spermatozoa, and the percentage of progressive motility or vigor was found. Abnormal spermatozoa not only showed a deformed shape, moreover there was an energetic motility system failure. The presence of SOD-like activity in seminal plasma, spermatic, and postspermatic fractions of canine semen was demonstrated for the first time.     

Coisolation of glutathione peroxidase, catalase and superoxide dismutase from human erythrocytes

Glutathione peroxidase (GSH-Px; glutathione: hydrogen peroxide oxidoreductase; EC 1.11.1.9), catalase (H2O2: H2O2 oxidoreductase; EC 1.11.1.6) and superoxide dismutase (superoxide: superoxide oxidoreductase; EC 1.15.1.1) were coisolated from human erythrocyte lysate by chromatography on DEAE-cellulose. Glutathione peroxidase was separated from superoxide dismutase and catalase by thiol-disulfide exchange chromatography and then purified to approximately 90% homogeneity by gel permeation chromatography and dye-ligand affinity chromatography. Catalase and superoxide dismutase were separated from each other and purified further by gel permeation chromatography. Catalase was then purified to approximately 90% homogeneity by ammonium sulfate precipitation and superoxide dismutase was purified to apparent homogeneity by hydrophobic interaction chromatography. The results for glutathione peroxidase represent an improvement of approximately 10-fold in yield and 3-fold in specific activity compared with the established method for the purification of this enzyme. The yields for superoxide dismutase and catalase were high (45 mg and 232 mg, respectively, from 820 ml of washed packed cells), and the specific activities of both enzymes were comparable to values found in the literature.     

A trifunctional enzyme with glutathione S-transferase,glutathione peroxidase and superoxide dismutase activity

Superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione S-transferase (GST) and glutathione reductase (GR) play crucial roles in balancing the production and decomposition of reactive oxygen species (ROS) in living organisms. These enzymes act cooperatively and synergistically to scavenge ROS, as not one of them can singlehandedly clear all forms of ROS. In order to imitate the synergy of the enzymes, we designed and generated a recombinant protein, which comprises of a Schistosoma japonicum GST (SjGST) and a bifunctional 35-mer peptide with SOD and GPX activities. The engineered protein demonstrated SOD, GPX and GST activities simultaneously. This trifunctional enzyme with SOD, GPX and GST activities is expected to be the best ROS scavenger.     

Correlative links between superoxide dismutase, catalase and glutathione peroxidase activities in mouse liver

Qualitative and quantitative differences in correlative and regressive links between superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase were assessed in the mice liver by two- and three-dimensional statistical methods. Paired linear correlation analysis indicated SOD-CAT tandem as the correlatively acting enzymatic pair. Three-dimensional analysis revealed uniform response surfaces which exhibited higher activities at disproportional values of the other two and lower activities at proportional activities of the other two enzymes. The direct effect of the enzymes on each other was positive [table: see text] while the effect of their product was always negative.     

Radiation resistance and the CuZn superoxide dismutase, Mn superoxide dismutase, catalase, and glutathione peroxidase activities of seven human cell lines

CuZn superoxide dismutase, Mn superoxide dismutase, catalase, and glutathione peroxidase form the primary enzymic defense against toxic oxygen reduction metabolites in cells. To test the importance of these protective enzymes in the cellular radiation response, the enzymic activities of seven different human cell lines were determined in parallel with their clonogenic survival characteristics. A positive correlation between the content of glutathione peroxidase in cell lines and their extrapolation numbers (n) and quasithreshold doses (Dq) was detected. Between the cellular contents of the other enzymes and D0, n, and Dq no positive correlations could be established. An interesting finding was a very high Mn superoxide dismutase content in a malignant mesothelioma cell line P7, which had an extremely high D0, 5.0 Gy.     

Effects of catechin and epicatechin on superoxide dismutase and glutathione peroxidase activity,in vivo

Abstract

Objectives

The objective of this study was to investigate the effects of catechin and epicatechin on the activity of the endogenous antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) (as well as the total antioxidant capacity (TAC)) of rats after intra-peritoneal (i.p.) administration.

Methods

Twenty-four Wistar rats were randomly divided into two groups: the experimental group which was administered daily with a 1:1 mixture of epicatechin and catechin at a concentration of 23 mg/kg body weight for 10 days and the control group which was injected daily with an equal amount of saline. Blood and urine samples were collected before and after the administration period, as well as 10 days after (follow-up).

Results

Intra-peritoneal administration of catechins led to a potent decrease in GPx levels and a significant increase in SOD levels. TAC was significantly increased in plasma and urine. Malonaldehyde levels in urine remained stable. In the animals treated with catechins, SOD activity showed a moderate negative correlation with GPx activity.

Discussion

Boosting the activity of the antioxidant enzymes could be a potential adjuvant approach for the treatment of the oxidative stress-related diseases.     

Vanadium effect on the activity of horseradish peroxidase, catalase, glutathione peroxidase, and superoxide dismutase in vitro.

The effect of vanadium (V) on the activity of horseradish peroxidase, catalase, glutathione peroxidase, and superoxide dismutase has been studied. A competitive inhibition pattern was evident for vanadate ions on the activity of horseradish peroxidase (Ki = 41.2 microM). No significant inhibitory effects were found when V(V) was tested with catalase and when either V(IV) or V(V) were assayed with glutathione peroxidase. For the latter, the effect of V on the different components of the reaction system was investigated. V(V) did not significantly affect SOD activity when assayed with the sulfite method, which is devoid of interferences with V(V); however, there was an apparent inhibitory dose-response pattern for either V(IV) or V(V) using the pyrogallol assay, owing to an interference of pyrogallol with the metal. Besides, no significant binding of V(IV) or V(V) to the enzyme could be demonstrated. The lack of a direct inhibitory effect of V on the activity of the main antioxidant enzymes suggests that many biological and toxicological effects of V may be mediated more by oxidative reactions of the metal or of its complexes with physiologically relevant biomolecules than by a direct modulation of enzymatic activities.     

Activity of glutathione peroxidase, glutathione reductase, and lipid peroxidation in erythrocytes in workers exposed to lead

The aim of this study was to estimate the activity of glutathione peroxidase (GPx), glutathione reductase (GR), and malondialdehyde (MDA) in erythrocytes in healthy male employees of zinc and lead steelworks who were occupationally exposed to lead over a long period of time (about 15 yr). Workers were divided into two subgroups: the first included employees with low exposure to lead (LL) (n=75) with blood lead level PbB=25–40 μg/dL and the second with high exposure to lead (HL) (n=62) with PbB over 40 μg/dL. Administration workers (n=35) with normal levels of PbB and zinc protoporphyrin in blood (ZPP) in blood were the control group. The activity of GPx significantly increased in LL when compared to the control group (p<0.001) and decreased when compared to the HL group (p=0.036). There were no significant changes in activity of GR in the study population. MDA erythrocyte concentration significantly increased in the HL group compared to the control (p=0.014) and to the LL group (p=0.024). For the people with low exposure to lead (PbB=25–40 μg/dL), the increase of activity of GPx by about 79% in erythrocytes prevented lipid peroxidation and it appears to be the adaptive mechanism against the toxic effect of lead. People with high exposure to lead (with PbB over 40 μg/dL) have shown an increase in MDA concentration in erythrocytes by about 91%, which seems to have resulted from reduced activity of GPx and the lack of increase in activity of GR in blood red cells.     

A supramolecular bifunctional artificial enzyme with superoxide dismutase and glutathione peroxidase activities

For constructing a bifunctional antioxidative enzyme with both superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, a supramolecular artificial enzyme was successfully constructed by the self-assembly of the Mn(III)meso-tetra[1-(1-adamantyl methyl ketone)-4-pyridyl] porphyrin (MnTPyP-M-Ad) and cyclodextrin-based telluronic acid (2-CD-TeO₃H) through host-guest interaction in aqueous solution. The self-assembly of the adamantyl moieties of Mn(III) porphyrin and the β-CD cavities of 2-CD-TeO₃H was demonstrated by the NMR spectra. In this supramolecular enzyme model, the Mn(III) porphyrin center acted as an efficient active site of SOD and tellurol moiety endowed GPx activity. The SOD-like activity (IC₅₀) of the new catalyst was found to be 0.116 μM and equals to 2.56% of the activity of the native SOD. Besides this, supramolecular enzyme model also showed a high GPx activity, and a remarkable rate enhancement of 27-fold compared to the well-known GPx mimic ebselen was observed. More importantly, the supramolecular artificial enzyme showed good thermal stability.     

Superoxide dismutase, glutathione peroxidase, and glutathione reductase in sheep organs

The enzyme activities of the superoxide dismutase (SOD), glutathione peroxidase (GSHPx), glutathione reductase (GR) and thiobarbituric acid reactive substances (TBARS) content were measured in tissue extracts of the liver, kidney and lung of sheep in a nonpolluted control area (C), a polluted area pasture (PP) and those from polluted areas but fed in the laboratory with an experimental emission supplement diet (EEF). Compared with the control SOD, activity was significantly increased (1.75 times) only in the liver of the PP group. In the EEF group there was a tendency toward lower activities in all organs. The Cu,Zn-SOD isoenzymes pattern analyzed by isoelectrofocusing was different in the organs of the animals exposed to pollutants when compared with those of the controls. In the liver, two new isoenzymes with pI 5.30 and 5.70 were found in the PP group and an additional isoenzyme with pI 5.10 in the EEF group. The kidney isoenzymes with pl 5.30 and 5.40 were inhibited in the EEF group. In the lung, two new isoenzymes appeared with pl 5.30 and 5.40 in the PP group and two new isoenzymes with pI 6.10 and 6.50 in the EEF group. GSHPx activity was inhibited in the liver and kidney of the sheep exposed to pollutants. GR activity was significantly changed only in the liver. The activity in the PP group was 2.30 and 2.10 times higher than in the C and EEF groups, respectively. TBARS content was increased in the liver and kidney of the EEF group compared with the control.