Total Superoxide Dismutase Activity and Glutathione Peroxidase Activity in Plasma of Phenylketonuric Subjects Supplemented with Selenium

2002 ◽  
pp. 634-635
Author(s):  
M. Calomme ◽  
P. Cos ◽  
V. Ramaekers ◽  
B. François ◽  
M. Van Caillie-Bertrand ◽  
...  
2019 ◽  
Vol 112 (3) ◽  
pp. e263-e264
Author(s):  
Luchezar Vasilev Jelezarski ◽  
Dimitar Parvanov ◽  
Vilyana Georgieva ◽  
Rumiana Ganeva ◽  
Georgi Stamenov Stamenov

2007 ◽  
pp. 105-112
Author(s):  
J Kovačeva ◽  
J Pláteník ◽  
M Vejražka ◽  
S Štípek ◽  
T Ardan ◽  
...  

Under normal conditions, antioxidants at the corneal surface are balanced with the production of reactive oxygen species without any toxic effects. Danger from oxidative stress appears when natural antioxidants are overwhelmed leading to antioxidant/prooxidant imbalance. The aim of the present study was to examine the activities of enzymes contributing to the antioxidant/prooxidant balance in normal corneal epithelium of various mammals. The enzyme activities of antioxidant superoxide dismutase and glutathione peroxidase, as well as prooxidant xanthine oxidoreductase/xanthine oxidase were examined using biochemical methods. Results show that superoxide dismutase activity is high in rabbits and guinea pigs, whereas in pigs the activity is low and in cows it is nearly absent. In contrast, glutathione peroxidase activity is high in cows, pigs and rabbits, whereas in guinea pigs the activity is low. As far as prooxidant enzymes are concerned, elevated xanthine oxidoreductase/xanthine oxidase activities were found in rabbits, lower activities in guinea pigs, very low activity in cows and no activity in pigs. In conclusion, the above results demonstrate inter-species variations in activities of enzymes participating in antioxidant/prooxidant balance in the corneal epithelium. It is suggested that the levels of antioxidant and prooxidant enzymes studied in the corneal epithelium might be associated with the diurnal or nocturnal activity of animals. UV rays decompose hydrogen peroxide to damaging hydroxyl radicals and perhaps for this reason large animals with diurnal activity (cow, pig) require more effective peroxide removal (high glutathione peroxidase activity) together with the suppression of peroxide production (low superoxide dismutase activity, low xanthine oxidoreductase activity).


2000 ◽  
Vol 167 (3) ◽  
pp. 447-452 ◽  
Author(s):  
C Massafra ◽  
D Gioia ◽  
C De Felice ◽  
E Picciolini ◽  
V De Leo ◽  
...  

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.


1994 ◽  
Vol 266 (6) ◽  
pp. H2204-H2211
Author(s):  
R. K. Li ◽  
N. Shaikh ◽  
R. D. Weisel ◽  
W. G. Williams ◽  
D. A. Mickle

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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