scholarly journals Elevation in the Ratio of Cu/Zn-Superoxide Dismutase to Glutathione Peroxidase Activity Induces Features of Cellular Senescence and This Effect Is Mediated by Hydrogen Peroxide

1996 ◽  
Vol 5 (2) ◽  
pp. 283-292 ◽  
Author(s):  
Judy B. de Haan ◽  
Francesca Cristiano ◽  
Rocco Iannello ◽  
Cecile Bladier ◽  
Michael J. Kelner ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Superoxide Dismutase ◽  
Glutathione Peroxidase ◽  
Cellular Senescence ◽  
Peroxidase Activity ◽  
Glutathione Peroxidase Activity

scholarly journals Experience of measuring glutathione peroxidase activity in surgically induced endometrial-like lesions in rats

2021 ◽  
Vol 70 (2) ◽  
pp. 55-61
Author(s):  
Aleksey V. Razygraev ◽  
Elena V. Baziyan ◽  
Lyudmila S. Polyanskikh ◽  
Mariya A. Petrosyan
Keyword(s):  
Hydrogen Peroxide ◽  
Antioxidant Enzymes ◽  
Glutathione Peroxidase ◽  
Rat Model ◽  
Peroxidase Activity ◽  
Specific Activity ◽  
Reduced Glutathione ◽  
Glutathione Peroxidase Activity ◽  
Nitrobenzoic Acid ◽  
Surgically Induced

BACKGROUND: Endometriosis is known to be linked with altered activities of antioxidant enzymes and with their gene polymorphisms. Progestins are known to induce glutathione peroxidase activity in the endometrium and promote reduction of endometrial lesions. It could be useful to estimate the correlation between the activity of glutathione peroxidase within endometrial lesions and their degree of reduction. AIM: The present study was aimed at estimating glutathione peroxidase activity in surgically induced endometrial-like lesions of different degree of reduction in rat model of endometriosis. MATERIALS AND METHODS: The method for determining glutathione peroxidase activity using hydrogen peroxide as a substrate and 5,5-dithiobis(2-nitrobenzoic acid) for estimation of residual reduced glutathione was applied for quantitative analysis of the enzyme activity in endometriotic foci, surgically induced in female Wistar rats. An assay of glutathione peroxidase activity in tissue homogenates was performed at 37C in a reaction medium containing Tris-HCl buffer supplemented with tetrasodium ethylenediaminetetraacetate and sodium azide (pH 8.5) in the presence of 0.55 mM reduced glutathione and 0.192 mM hydrogen peroxide. Before adding trichloroacetic acid, 40-second incubation was used. The correlation between the specific activity of the enzyme and protein amount in endometriotic foci was estimated. RESULTS: In a rat model of endometriosis, there was a high, well-determined glutathione peroxidase activity in endometriotic foci. For the same endometriotic tissue sample, the enzymatic activity was proportional to the amount of protein in the reaction mixture. The range of specific glutathione peroxidase activity was 2.436.45 micromoles of consumed glutathione per minute per milligram of protein (n = 7). In most reduced endometriotic foci (with the minimum amount of endometriotic tissue), the highest specific activity of glutathione peroxidase was found (the Spearmans rho of 0.93 with p = 0.0067). CONCLUSIONS: The method for determining glutathione peroxidase activity using hydrogen peroxide and 5,5-dithiobis(2-nitrobenzoic acid) is convenient for working with the endometriotic tissue in a rat model of endometriosis. We can accept, with p 0.01, that weight of endometriotic foci is negatively linked with specific glutathione peroxidase activity within their tissue. The results are analogous to the previously obtained data on catalase activity and suggest the involvement of both antioxidant enzymes in reduction of endometrial lesions.

scholarly journals Effects of estrogens and androgens on erythrocyte antioxidant superoxide dismutase, catalase and glutathione peroxidase activities during the menstrual cycle

2000 ◽  
Vol 167 (3) ◽  
pp. 447-452 ◽  
Author(s):  
C Massafra ◽  
D Gioia ◽  
C De Felice ◽  
E Picciolini ◽  
V De Leo ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Menstrual Cycle ◽  
Glutathione Peroxidase ◽  
Peroxidase Activity ◽  
Free Testosterone ◽  
Cycle Phase ◽  
Activity Levels ◽  
Glutathione Peroxidase Activity ◽  
Antioxidant Enzyme System ◽  
Peroxidase Enzyme

The effects of physiological changes in estrogens and androgens on the erythrocyte antioxidant superoxide dismutase, catalase and glutathione peroxidase enzyme activities during the menstrual cycle were investigated in healthy eumenorrheic women. Blood samples were taken on alternate days from twelve normally cyclic women (age range: 20 to 27 years; mean age: 24.1 years) from the first day of one menstrual cycle until the first day of the subsequent one. Plasma was analyzed for FSH, LH, estradiol, progesterone, testosterone, free testosterone and androstenedione concentrations. Erythrocyte superoxide dismutase, catalase and glutathione peroxidase activities were evaluated on the same days and cycle length was standardized on the basis of the preovulatory estradiol peak. Significant cyclic phase-related changes were observed in glutathione peroxidase (P<0.05), with higher glutathione peroxidase activity levels from the late follicular to the early luteal phase compared with those found in the early follicular phase (P<0.001 and P<0.002 respectively). A significant positive correlation was observed between mean estradiol and glutathione peroxidase cycle-related variations (r=0.80, P<0.001), whereas no significant cycle phase-dependent changes were seen in superoxide dismutase and catalase. No effect of progesterone and androgens on the erythrocyte antioxidant enzyme system was documented. The findings indicate that physiological ovarian estradiol production during the menstrual cycle may have an important role in regulating erythrocyte glutathione peroxidase activity.

Oxyradical-induced antioxidant and lipid changes in cultured human cardiomyocytes

1994 ◽  
Vol 266 (6) ◽  
pp. H2204-H2211
Author(s):  
R. K. Li ◽  
N. Shaikh ◽  
R. D. Weisel ◽  
W. G. Williams ◽  
D. A. Mickle
Keyword(s):  
Superoxide Dismutase ◽  
Glutathione Peroxidase ◽  
Tetralogy Of Fallot ◽  
Peroxidase Activity ◽  
Membrane Lipid ◽  
Alpha Tocopherol ◽  
Low Oxygen ◽  
Conjugated Diene ◽  
Glutathione Peroxidase Activity ◽  
Human Cardiomyocytes

Because the chronically cyanotic myocardium is thought to be more susceptible to oxyradical injury than the noncyanotic myocardium during cardiovascular surgery, we studied the oxyradical susceptibility of human ventricular cardiomyocytes cultured at high and low oxygen tension (PO2) levels. Passage 4 tetralogy of Fallot cardiomyocytes were cultured at PO2 levels of 150 and 40 mmHg for 14 days and then exposed for 10 min to superoxide radicals. The cellular levels of ATP, phospholipid fatty acids, phospholipid conjugated dienes, alpha-tocopherol, and activities of superoxide dismutase, catalase, and glutathione peroxidase were measured. ATP levels decreased more markedly in the low-PO2 group. Although the decrease in alpha-tocopherol levels was similar for both groups, phospholipid conjugated diene formation and phospholipid unsaturated fatty acid loss was greater in the low-PO2 cells. Glutathione peroxidase activity was rapidly inhibited. Superoxide dismutase activity was unaffected, and catalase activity was inhibited by no more than 50%. Although extracellular superoxide dismutase with catalase did not inhibit phospholipid conjugated diene formation and phospholipid breakdown, extracellular glutathione peroxidase with reduced glutathione did limit phospholipid damage. With the occurrence of membrane lipid peroxidation, the decreased glutathione peroxidase activity in the cyanotic tetralogy of Fallot myocardium determines cardiomyocyte membrane susceptibility to oxidant injury.

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