scholarly journals Deficient metabolic utilization of hydrogen peroxide in Trypanosoma cruzi

1980 ◽  
Vol 188 (3) ◽  
pp. 643-648 ◽  
Author(s):  
A Boveris ◽  
H Sies ◽  
E E Martino ◽  
R Docampo ◽  
J F Turrens ◽  
...  
Keyword(s):  
Glutathione Peroxidase ◽  
Trypanosoma Cruzi ◽  
Glutathione Reductase ◽  
Ascorbate Peroxidase ◽  
Peroxidase Activity ◽  
Reductase Activity ◽  
Alternative Pathway ◽  
Cumene Hydroperoxide ◽  
Glutathione Peroxidase Activity ◽  
Enzymic Oxidation

The glutathione peroxidase-glutathione reductase system, an alternative pathway for metabolic utilization of H2O2 [Chance, Sies & Boveris (1979) Physiol. Rev. 59, 527-605], was investigated in Trypanosoma cruzi, an organism lacking catalase and deficient in peroxidase [Boveris & Stoppani (1977) Experientia 33, 1306-1308]. The presence of glutathione (4.9 +/- 0.7 nmol of reduced glutathione/10(8) cells) and NADPH-dependent glutathione reductase (5.3 +/- 0.4 munit/10(8) cells) was demonstrated in the cytosolic fraction of the parasite, but with H2O2 as substrate glutathione peroxidase activity could not be demonstrated in the same extracts. With t-butyl hydroperoxide or cumene hydroperoxide as substrate, a very low NADPH-dependent glutathione peroxidase activity was detected (equivalent to 0.3-0.5 munit of peroxidase/10(8) cells, or about 10% of glutathione reductase activity). Blank reactions of the glutathione peroxidase assay (non-enzymic oxidation of glutathione by hydroperoxides and enzymic oxidation of NADPH) hampered accurate measurement of peroxidase activity. The presence of superoxide dismutase and ascorbate peroxidase activity in, as well as the absence of catalase from, epimastigote extracts was confirmed. Ascorbate peroxidase activity was cyanide-sensitive and heat-labile, but no activity could be demonstrated with diaminobenzidine, pyrogallol or guaiacol as electron donor. The summarized results support the view that T. cruzi epimastigotes lack an adequate enzyme defence against H2O2 and H2O2-related free radicals.

scholarly journals The effect of age and sex on glutathione reductase and glutathione peroxidase activities and on aerobic glutathione oxidation in rat liver homogenates

1969 ◽  
Vol 112 (1) ◽  
pp. 109-115 ◽  
Author(s):  
R E Pinto ◽  
W Bartley
Keyword(s):  
Glutathione Peroxidase ◽  
Glutathione Reductase ◽  
Rat Liver ◽  
Peroxidase Activity ◽  
Redox State ◽  
Reductase Activity ◽  
Glutathione Peroxidase Activity ◽  
Glutathione Reductase Activity ◽  
Liver Homogenates ◽  
Age And Sex

1. Changes in liver glutathione reductase and glutathione peroxidase activities in relation to age and sex of rats were measured. Oxidation of GSH was correlated with glutathione peroxidase activity. 2. Glutathione reductase activity in foetal rat liver was about 65% of the adult value. It increased to a value slightly higher than the adult one at about 2–3 days, decreased until about 16 days and then rose after weaning to a maximum at about 31 days, finally reaching adult values at about 45 days old. 3. Weaning rats on to an artificial rat-milk diet prevented the rise in glutathione reductase activity associated with weaning on to the usual diet high in carbohydrate. 4. In male rats glutathione peroxidase activity in the liver increased steadily up to adult values. There were no differences between male and female rats until sexual maturity, when, in females, the activity increased abruptly to an adult value that was about 80% higher than that in males. 5. The rate of GSH oxidation in rat liver homogenates increased steadily from 3 days until maturity, when the rate of oxidation was about 50% higher in female than in male liver. 6. In the liver a positive correlation between glutathione peroxidase activity and GSH oxidation was found. 7. It is suggested that the coupled oxidation–reduction through glutathione reductase and glutathione peroxidase is important for determining the redox state of glutathione and of NADP, and also for controlling the degradation of hydroperoxides. 8. Changes in glutathione reductase and glutathione peroxidase activities are discussed in relation to the redox state of glutathione and NADP and to their effects on the concentration of free CoA in rat liver and its possible action on ketogenesis and lipogenesis.

scholarly journals Abnormal antioxidant defence in some tissues of congenitally obese mice

1984 ◽  
Vol 219 (1) ◽  
pp. 41-49 ◽  
Author(s):  
I D Capel ◽  
H M Dorrell
Keyword(s):  
Glutathione Peroxidase ◽  
Peroxidase Activity ◽  
Cumene Hydroperoxide ◽  
Hepatic Tissue ◽  
Obese Mice ◽  
Glutathione Peroxidase Activity ◽  
Antioxidant Defence ◽  
Reactive Material ◽  
Antioxidant Defence System ◽  
Significant Difference

The concentration of lipoperoxides (estimated as thiobarbituric acid-reactive material) and some components of the antioxidant defence system have been compared in various tissues of lean and congenitally obese mice. NADPH-stimulated lipoperoxide generation in vitro was significantly higher in microsomes (microsomal fractions) prepared from obese hepatic tissue than lean. Plasma, liver and brain lipoperoxide concentration was significantly higher in obese mice. In blood derived from obese mice the concentration of non-enzymic antioxidants including caeruloplasmin and vitamin A was higher, but hepatic retinol concentration was lower in these animals. In all the tissues assayed the glutathione peroxidase activity against H2O2 was less than its activity against cumene hydroperoxide. Assayed with either substrate, glutathione peroxidase activity was significantly higher in the brain and blood of obese mice than their lean counterparts. Conversely, liver glutathione peroxidase was decreased in obese animals, representing 43% of the activity of the lean-mouse liver enzyme against H2O2 and 81% of the cumene hydroperoxide-reducing activity. The liver of obese mice had significantly less, and the kidneys more, oxidized glutathione than the corresponding tissues of lean mice. Further investigations on hepatic tissue indicated that glutathione reductase activity was lower in the obese animals, but there was no significant difference between glucose-6-phosphate dehydrogenase activity in obese and lean mice.

scholarly journals Glutathione metabolism system under condition of transplantation of muscle tissue in rats

2015 ◽  
Vol 6 (1) ◽  
pp. 23-27
Author(s):  
O. V. Kulibaba ◽  
S. M. Kozishkurt ◽  
O. O. Duzenko ◽  
I. L. Vovchuk ◽  
S. A. Petrov
Keyword(s):  
Glutathione Peroxidase ◽  
Glutathione Reductase ◽  
Muscle Tissue ◽  
Peroxidase Activity ◽  
Abdominal Muscle ◽  
The Body ◽  
Male Rats ◽  
Special Role ◽  
Glutathione Peroxidase Activity ◽  
Femoral Muscle

The paper presents the results of determining the amount of reduced glutathione, glutathione reductase and glutathione peroxidase activity at transplantation of muscle tissue taken from rats from the same litter. During the work 2 surgical interventions were carried out: transplantation of muscle tissue taken from the same litter of rats, and operation without replanting. Transplantation was performed on nonlinear white male rats weighing 180–300 g. The animals were taken out of the experiment by passing electric current through the medulla oblongata. For donor transplants males from the same litter were used. In adult donor rats abdominal muscle tissue was extracted and transplanted to homologous tissue of the recipient rat. The same procedure was carried out with femoral muscle tissue. Operation without replanting was used to compare the effects of changes in the number of investigated parameters of the surgical exposure. Tissue not subject to any surgery served as a control. Parameters under study were determined on the first, third and seventh day after transplantation. Glutathione levels in tissues were determined byE. Butler, A. Dyubona, B. Kelly. Determination of glutathione reductase is based on the reduction of NADPH registration. Glutathione peroxidase activity was determined by accumulation of oxidized glutathione. Surgery is known to lead to expression of oxidative stress in the organs operated. Special role in antioxidant protection of the body is given to thiols. Expressed hydrophilic properties provide their high content in water fraction of cells and ability to protect biologically important molecules (enzymes, nucleic acids, hemoglobin) from oxidative damage. Property of thiol compounds is known to inhibit both fermented and not fermented free radical oxidation. For the first time it was found that transplantation of muscle tissue taken from animals from the same litter lead to significant reduction of glutathione in the femoral muscle of the recipient and abdominal muscle tissue of the donor and recipient and to significant increase in glutathione reductase activity in the femoral muscle tissue of the donor and in the abdominal muscle tissue of the donor and recipient. 

scholarly journals Basic components of glutathion system in rat erythrocytes under conditions of toxic damage on the background of an alimental protein lack

2020 ◽  
Vol 12 (1) ◽  
pp. 31-38
Author(s):  
Halyna Kopylchuk ◽  
Ivanna Nykolaichuk
Keyword(s):  
Glutathione Peroxidase ◽  
Glutathione Reductase ◽  
Peroxidase Activity ◽  
Glutathione Transferase ◽  
Reduced Glutathione ◽  
Oxidized Glutathione ◽  
Glutathione Peroxidase Activity ◽  
Rat Erythrocytes ◽  
Toxic Damage ◽  
Glucose 6 Phosphate Dehydrogenase

The article is devoted to the study of the main components of the glutathione system under conditions of toxic damage against the background of nutritional protein deficiency: the content of reduced and oxidized glutathione with the determination of the GSH/GSSG ratio, the activity of glutathione-dependent enzymes – glutathione peroxidase, glutathione transferase, glutathione reductase, and glucose-6-phosphate dehydrogenase. The concentration of reduced glutathione in the erythrocyte hemolysate was studied using Elman's reagent after deproteinization of the samples. Glutathione transferase activity was determined by the rate of formation of glutathione S conjugates by reacting reduced glutathione with a substrate of 1-chloro-2.4-dinitrobenzene. Glutathione peroxidase activity was evaluated by the formation of oxidized glutathione. The activity of glutathione reductase in erythrocytes was determined by the method, is based on measuring the oxidation rate of NADPH+H+, which is recorded by decreasing absorption at a wavelength of 340 nm. A decrease in the ratio of GSH/GSSG in rat erythrocytes under conditions of toxic damage against a nutritional deficiency of protein is indicated by a functional shift in the thiol-disulfide balance towards increased use of the reduced form of glutathione for antioxidant protection. It was established that toxic damage is a key factor in reducing the level of glutathione transferase against the background of an increase in glutathione peroxidase activity in rat erythrocytes, the activation of which probably prevents the progression of LPO processes. At the same time, under conditions of toxic damage, against the background of alimentary protein deficiency, a decrease in glutathione reductase and glucose-6-phosphate dehydrogenase activity is observed, which leads to blocking of the first stage of glucose-6-phosphate metabolism in the pentose phosphate cycle, resulting in a decrease in the amount of NADPH and, accordingly reduced glutathione.

Low Selenium Status in the Elderly Influences Thyroid Hormones

1995 ◽  
Vol 89 (6) ◽  
pp. 637-642 ◽  
Author(s):  
Oliviero Olivieri ◽  
Domenico Girelli ◽  
Margherita Azzini ◽  
Anna Maria Stanzial ◽  
Carla Russo ◽  
...  
Keyword(s):  
Glutathione Peroxidase ◽  
Thyroid Hormones ◽  
Peroxidase Activity ◽  
Controlled Trial ◽  
The Elderly ◽  
Serum Selenium ◽  
Selenium Status ◽  
Glutathione Peroxidase Activity ◽  
Double Blind ◽  
Double Blind Placebo

1. Iodothyronine 5′-deiodinase, which is mainly responsible for peripheral triiodothyronine (T3) production, has recently been demonstrated to be a selenium-containing enzyme. In the elderly, reduced peripheral conversion of thyroxine (T4) to T3 and overt hypothyroidism are frequently observed. 2. We measured serum selenium and erythrocyte glutathione peroxidase (as indices of selenium status), thyroid hormones and thyroid-stimulating hormone in 109 healthy euthyroid subjects (52 women, 57 men), carefully selected to exclude abnormally low thyroid hormone levels induced by acute or chronic diseases or calorie restriction. The subjects were subdivided into three age groups. To avoid conditions of undernutrition or malnutrition, dietary records were obtained for a sample of 24 subjects, randomly selected and representative of the whole population for age and sex. 3. In order to properly assess the influence of selenium status on iodothyronine 5′-deiodinase type I activity, a double-blind placebo-controlled trial was also carried out on 36 elderly subjects, resident at a privately owned nursing home. 4. In the free-living population, a progressive reduction of the T3/T4 ratio (due to increased T4 levels) and of selenium and erythrocyte glutathione peroxidase activity was observed with advancing age. A highly significant linear correlation between T4, T3/T4 and selenium was observed in the population as a whole (for T4, R = −0.312, P < 0.002; for T3/T4 ratio, R = 0.32, P < 0.01) and in older subjects (for T4, R = −0.40, P < 0.05; for T3/T4 ratio, R = 0.54, P < 0.002). 5. The main result of the double-blind placebo-controlled trial was a significant improvement of selenium indices and a decrease in the T4 level in selenium-treated subjects; serum selenium, erythrocyte glutathione peroxidase activity and thyroid hormones did not change in placebo-treated subjects. 6. We concluded that selenium status influences thyroid hormones in the elderly, mainly modulating T4 levels.

scholarly journals Selenium levels and glutathione peroxidase activity in patients with ataxia-telangiectasia: association with oxidative stress and lipid status biomarkers

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Itana Gomes Alves Andrade ◽  
Fabíola Isabel Suano-Souza ◽  
Fernando Luiz Affonso Fonseca ◽  
Carolina Sanchez Aranda Lago ◽  
Roseli Oselka Saccardo Sarni
Keyword(s):  
Oxidative Stress ◽  
Glutathione Peroxidase ◽  
Peroxidase Activity ◽  
Oxidized Ldl ◽  
Reference Value ◽  
Glutathione Peroxidase Activity ◽  
Oxidative Stress Biomarkers ◽  
Apo B ◽  
Lipid Status ◽  
And Oxidative Stress

Abstract Introduction Ataxia-Telangiectasia (A-T) is a multi-system disorder that may be associated with endocrine changes, oxidative stress in addition to inflammation. Studies suggest that selenium is a trace element related to protection against damage caused by oxidative stress. Objective To describe the plasma levels of selenium and erythrocyte glutathione peroxidase activity in A-T patients and to relate them to oxidative stress and lipid status biomarkers. Methods This is a cross-sectional and controlled study evaluating 22 A-T patients (age median, 12.2 years old) matched by gender and age with 18 healthy controls. We evaluated: nutritional status, food intake, plasma selenium levels, erythrocyte glutathione peroxidase activity, lipid status, inflammation and oxidative stress biomarkers. Results Adequate levels of selenium were observed in 24/36 (66.7%) in this evaluated population. There was no statistically significant difference between the groups in selenium levels [47.6 μg/L (43.2–57.0) vs 54.6 (45.2–62.6) μg/dL, p = 0.242]. Nine of A-T patients (41%) had selenium levels below the reference value. The A-T group presented higher levels of LDL-c, non-HDL-c, oxidized LDL, Apo B, Apo-B/Apo-A-I1, LDL-c/HDL-c ratio, malondialdehyde [3.8 µg/L vs 2.8 µg/L, p = 0.029] and lower Apo-A-I1/HDL-c and glutathione peroxidase activity [7300 U/L vs 8686 U/L, p = 0.005]. Selenium levels were influenced, in both groups, independently, by the concentrations of oxidized LDL, malonaldehyde and non-HDL-c. The oxidized LDL (AUC = 0.849) and ALT (AUC = 0.854) were the variables that showed the greatest discriminatory power between groups. Conclusion In conclusion, we observed the presence of selenium below the reference value in nearly 40% and low GPx activity in A-T patients. There was a significant, inverse and independent association between selenium concentrations and oxidative stress biomarkers. Those data reinforce the importance of assessing the nutritional status of selenium in those patients.

scholarly journals The distribution, induction and isoenzyme profile of glutathione S-transferase and glutathione peroxidase in isolated rat liver parenchymal, Kupffer and endothelial cells

1989 ◽  
Vol 264 (3) ◽  
pp. 737-744 ◽  
Author(s):  
P Steinberg ◽  
H Schramm ◽  
L Schladt ◽  
L W Robertson ◽  
H Thomas ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Glutathione Peroxidase ◽  
Rat Liver ◽  
Peroxidase Activity ◽  
Cell Types ◽  
Transferase Activity ◽  
Glutathione Peroxidase Activity ◽  
Glutathione S Transferase ◽  
Liver Parenchymal ◽  
Parenchymal Cells

The distribution and inducibility of cytosolic glutathione S-transferase (EC 2.5.1.18) and glutathione peroxidase (EC 1.11.1.19) activities in rat liver parenchymal, Kupffer and endothelial cells were studied. In untreated rats glutathione S-transferase activity with 1-chloro-2,4-dinitrobenzene and 4-hydroxynon-2-trans-enal as substrates was 1.7-2.2-fold higher in parenchymal cells than in Kupffer and endothelial cells, whereas total, selenium-dependent and non-selenium-dependent glutathione peroxidase activities were similar in all three cell types. Glutathione S-transferase isoenzymes in parenchymal and non-parenchymal cells isolated from untreated rats were separated by chromatofocusing in an f.p.l.c. system: all glutathione S-transferase isoenzymes observed in the sinusoidal lining cells were also detected in the parenchymal cells, whereas Kupffer and endothelial cells lacked several glutathione S-transferase isoenzymes present in parenchymal cells. At 5 days after administration of Arocolor 1254 glutathione S-transferase activity was only enhanced in parenchymal cells; furthermore, selenium-dependent glutathione peroxidase activity decreased in parenchymal and non-parenchymal cells. At 13 days after a single injection of Aroclor 1254 a strong induction of glutathione S-transferase had taken place in all three cell types, whereas selenium-dependent glutathione peroxidase activity remained unchanged (endothelial cells) or was depressed (parenchymal and Kupffer cells). Hence these results clearly establish that glutathione S-transferase and glutathione peroxidase are differentially regulated in rat liver parenchymal as well as non-parenchymal cells. The presence of glutathione peroxidase and several glutathione S-transferase isoenzymes capable of detoxifying a variety of compounds in Kupffer and endothelial cells might be crucial to protect the liver from damage by potentially hepatotoxic substances.

Glutathione peroxidase activity in patients with renal disorders

2005 ◽  
Vol 9 (2) ◽  
pp. 127-131 ◽  
Author(s):  
Mohamed A. El-far ◽  
Mohamed A. Bakr ◽  
Sami E. Farahat ◽  
Elsaid A. Abd El-Fattah
Keyword(s):  
Glutathione Peroxidase ◽  
Peroxidase Activity ◽  
Glutathione Peroxidase Activity ◽  
Renal Disorders
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