conclusions plasma se and gpx levels were lower in type two diabetic patients with macroalbuminuria and related to the stage of diabetic nephropathy. results plasma se and gpx concentrations were significantly lower in diabetic patients with macroalbuminuria than other study groups (p < 0.001). albuminuria (alb/cr in random urine sample) had a negative correlation with plasma se (r = -0.40, p =...

Extracellular glutathione peroxidase (eGPx) is a secreted selenoenzyme with GPx activity. eGPx protein and activity are found in blood plasma and other extracellular fluids. eGPx in plasma is predominantly derived from the proximal tubules of kidneys in humans. Two types of human proximal tubule cells were cultured on semipermeable polycarbonate membranes to determine whether these cells secret...

Fifteen second-parity sows were used to determine the importance of vitamin E (E) and selenium (Se) supplementation of the sow's diet and colostrum consumption by the neonatal pig on tolerance to parenteral iron. Selenium (.1 ppm) and E (50 IU/kg) supplementation of the diet of the sow increased plasma tocopherol and Se concentrations, but did not increase plasma glutathione peroxidase (GSH-Px)...

Controversial data exist concerning the relation between the activities of scavenger antioxidant enzymes and coronary heart disease (CHD) risk. The authors report updated meta-analyses of studies assessing the activities of 3 antioxidant enzymes--glutathione peroxidase, superoxide dismutase, and catalase--and CHD risk. Computer-based and manual searches of the relevant literature from January 1...

Previous studies (1,2) have shown the presence of a peroxidase in erythrocytes which catalyzes the breakdown of hydrogen peroxide with reduced glutathione serving as a hydrogen donor. The significance of this enzyme in the protection of hemoglobin from oxidative breakdown has been shown previously (2). The erythrocyte reduced glutathione peroxidase has now been purified by column chromatography...

By isolation of a mixed disulfide product of glutathione and cysteine, glutathione peroxidase was shown to be highly specific for only one donor substrate. Using the coupled assay of NADPH and yeast glutatione reductase, which is highly specific for flutathione disulfide, it was shown that the apparent inhibition of glutathione peroxidase by mercaptoethanol can be described kinetically and that...

Selenoprotein P is an extracellular protein containing presumably 10 selenocysteines that are encoded by the UGA stop codon in the open reading frame of the mRNA. The function of selenoprotein P is currently unknown, although several indirect lines of evidence suggest that selenoprotein P is a free radical scavenger. We first developed a conventional procedure to isolate selenoprotein P from hu...

An optimized coupled test system for glutathione peroxidase in red blood cells is presented. In the improved assay, tert. butyl hydroperoxide was employed as an acceptor substrate at twenty times Km(app) concentration. By aid of a batching procedure for instant separation of hemoglobin from glutathione peroxidase, it could be proved that cyanmethemoglobin in the modified procedure does not affe...