Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1260386 (GSH)
 38,102 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Our previous studies on cultured rabbit lens epithelial cells from 4-day-old rabbits showed that the glutathione redox cycle plays an important role in detoxifying H2O2, a potentially damaging oxidant present in the aqueous humor. Here we report the effect of donor age and cell density on the ability of cultured rabbit lens epithelial cells to detoxify H2O2. Lens epithelial cells (8 x 10(5] from a 4-day-old and an 8-year-old rabbit were cultured for 3 hr in minimal essential medium (MEM) or in MEM containing 0.01-0.1 mM H2O2 maintained with glucose oxidase. We determined the effect of H2O2 on the level of reduced glutathione (GSH), hexose monophosphate shunt activity, cell growth, and morphology. For growth studies, cells were exposed to the desired concentration of H2O2 for 3 hr and then cultured in MEM plus 10% rabbit serum for 7 days and counted. Young and old untreated cells contained high levels (30-40 nmol/8 x 10(5) cells) of GSH. Cells from 4-day-old rabbits tolerated 0.03 mM H2O2 with no effect on GSH and a minimal decrease in subsequent cell growth. However, in the older cells, GSH and growth were substantially diminished following treatment with 0.03 mM H2O2. Cells plated out at high density (8 x 10(5] were more tolerant of 0.03 mM H2O2 than cells plated out at low density (5 x 10(4]. Maximum shunt activity in the younger cells exposed to H2O2 was twice that of the older cells and occurred at a higher level of H2O2 (0.04 compared with 0.03 mM). Enzyme activities in untreated young and old cells were comparable for hexokinase, glucose-6-phosphate dehydrogenase, and glutathione peroxidase. However, glutathione reductase activity was 50% lower in the cells from the 8-year-old rabbit. The toxicity of H2O2 to cultured lens epithelial cells was directly related to donor age and inversely related to cell density. The damage in the older lens epithelial cells at 0.03 mM H2O2 was apparently due, in part, to a diminished response of the glutathione redox cycle to oxidative challenge.
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PMID:Influence of the activity of glutathione reductase on the response of cultured lens epithelial cells from young and old rabbits to hydrogen peroxide. 335 66

Periportal and perivenous hepatocytes were isolated by the digitonin-collagenase perfusion technique. The activity of the cytosolic glutathione S-transferase was higher in perivenous cells, but the cytosolic glutathione reductase and the microsomal glutathione S-transferase activities were evenly distributed. In contrast, both the Se-dependent and the microsomal Se-independent glutathione peroxidase activity and the glucose-6-phosphate dehydrogenase activity was much lower in perivenous hepatocytes, suggesting that these cells have a lowered detoxification capacity, which may contribute to their greater susceptibility to damage by xenobiotics. The mechanism of the ethanol-induced GSH depletion in vivo was studied by incubating conventionally isolated hepatocytes. In the absence of glutathione precursors, ethanol (80 mM) did not influence the GSH content, despite accumulation of acetaldehyde (10-100 MicroM). L-Methionine or L-cysteine stimulated GSH replenishment to in vivo rates. Ethanol oxidation resulted in acetaldehyde accumulation, but did not inhibit GSH replenishment from L-methionine and even stimulated that from L-cysteine. This seems to exclude conjugation of GSH with acetaldehyde as a mechanism by which ethanol suppresses GSH levels in vivo.
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PMID:Glutathione metabolism in isolated rat hepatocytes: acinar heterogeneity of detoxifying enzymes and effects of ethanol. 342 86

In the present research we have assayed the glucose-6-phosphate dehydrogenase, superoxide dismutase activities and reduced glutathione content in human cataractous lenses of 83 Sicilian subjects. Five of 45 males were G6PD deficient, whereas eight of 38 females showed a significant reduction in G6PD by 50%. The five males hemizygous for G6PD defect showed undetectable G6PD activity and low GSH levels in their lenses when compared to cataractous patients without erythrocyte G6PD deficiency; on the contrary, the specific activity of lenticular total SOD was found to be significantly increased. The G6PD and SOD activities as well as GSH levels, in the lenses of eight females with intermediate erythrocyte G6PD levels, were not significantly different when compared to females with normal erythrocyte G6PD activity.
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PMID:Superoxide dismutase activity and reduced glutathione content in cataractous lens of patients with glucose-6-phosphate dehydrogenase deficiency. 343 59

Single, preexposure, parenteral injection with both recombinant tumor necrosis factor/cachectin (TNF/C) and interleukin-1 (IL-1) prolonged the survival of rats (144 +/- 9 h) in continuous hyperoxia (greater than 99% O2 at 1 atm) when compared with rats injected with boiled TNF/C and boiled IL-1 (61 +/- 2 h), TNF/C alone (61 +/- 2 h), IL-1 alone (62 +/- 2 h), or saline (64 +/- 3 h). After exposure to hyperoxia for 52 h, pleural effusion volume, pulmonary artery pressure, total pulmonary resistance, and lung morphologic damage were decreased in those rats given TNF/C and IL-1 as compared with saline-injected rats. In parallel, ratios of reduced (GSH) to oxidized (GSSG) glutathione were greater (P less than 0.05) in lungs of TNF/C + IL-1-injected rats (91 +/- 20) than of saline-injected rats (30 +/- 4) that had been exposed to hyperoxia for 52 h. No differences were found in superoxide dismutase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase, or catalase activities in lungs of TNF/C + IL-1- or saline-treated, hyperoxia-exposed rats. Our results indicate that pretreatment with TNF/C and IL-1 favorably altered lung glutathione redox status, decreased lung injury, and enhanced survival of rats exposed to hyperoxia.
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PMID:Recombinant tumor necrosis factor/cachectin and interleukin 1 pretreatment decreases lung oxidized glutathione accumulation, lung injury, and mortality in rats exposed to hyperoxia. 349 53

Human red cells were labelled with [14C]cyanate, non-oxidant, permeant reagent that binds irreversibly to amino groups in proteins. Cyanate did not modify GSH levels, nor glucose-6-phosphate dehydrogenase (G6PD) activity when added at the labelling concentration i.e. c. 0.5 mM. Phagocytes were human monocytes, isolated and plated on 16 mm diameter plastic wells. Each well was plated with 40-70 X 10(3) cells. Monocytes were quantified by DNA assay with the DNA intercalating fluorescent compound Hoechst 33,258. The basal phagocytic rate of normal red cells by monocytes was 0.34 +/- 0.21 red cell per monocyte. Treatment of normal red cells with 20 microM diamide, or 50-100 microM chromate enhanced this rate 10-15-fold. 10 microM diamide or chromate were sufficient to stimulate phagocytosis of G6PD-deficient (Mediterranean variant) red cells.
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PMID:Measurement of phagocytosis utilizing [14C]cyanate-labelled human red cells and monocytes. 360 63

This study was designed to assess the effects of a moderate increase in dietary sulphur (S) in cattle. Twelve animals were initially fed a basal concentrate (S = 0.2%) and then divided into two groups; one fed basal and the other high S (S = 0.75%) concentrates. Health, body weight gains, and activities of erythrocyte enzymes-glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), glucose-6-phosphate dehydrogenase (G6PD), acetylcholinesterase (AChE), plasma- asparate aminotransferase (AST), and whole blood concentrations of selenium (Se) were monitored at various stages of the study. Marked increases in the activities of GSH-Px, SOD and G6PD from the pretrial values were observed upon initial feeding of basal concentrate diet. Sex related differences were not evident in enzyme activities and Se concentrations of the blood. A high linear correlation (r = 0.92) between averages of GSH-Px activity and Se concentration of blood was observed in both sexes. Increasing the amount of S in the concentrate diet (from 0.2 to 0.75%) did not produce any statistically significant change in enzyme activities and Se concentrations, body weight gains, and health of the cattle during the 85 days feeding period. The results indicate that a moderate increase in the dietary S would not impair Se and copper status or cause related disorders in cattle.
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PMID:Effects of high dietary sulphur on enzyme activities, selenium concentrations and body weights of cattle. 360 49

The effect of (1-benzoyl-1H-indazol-3-yl)oxylacetate L-Lysine (bendazac-lysine) on some enzymatic activities involved in the metabolism of reduced glutathione (GSH) was studied in the rabbit lens during developing cataract induced by a single dose of X-rays (2000 rads). The specific activities of glutathione reductase (G.R.), glutathione peroxidase (GSH.Px) and glutathione S-transferase (GSHS-tr.) do not change following irradiation and treatment with bendazac-lysine. The activity of the same enzymes expressed as a function of water soluble proteins (WSP) per lens significantly decreases (P less than 0.01) as compared to controls in the irradiated lens not treated with bendazac-lysine (ILNTB) at the 8th week, whereas no significant decrease as compared to controls is observed in the irradiated lens treated with bendazac-lysine (ILTB). In the ILNTB the specific activity of glucose-6-phosphate dehydrogenase (G6PDH) is reduced by 10% after 0.3 weeks and by 29% after 12 weeks. In the ILTB the specific activity of G6PDH is reduced by 8% after 0.3 weeks and by 14.5% after 12 weeks. The specific activity of superoxide dismutase (SOD) in the ILNTB is reduced by 19% after 0.3 weeks and reached 31% after 12 weeks. In the ILTB the specific activity of SOD is reduced by 11% after 0.3 weeks and 19.8% after 12 weeks. The mechanism of protective effect of bendazac-lysine on cataract is discussed.
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PMID:Effects of bendazac L-lysine salt on some metabolic enzymes of glutathione in the rabbit lens after X-irradiation. 361 May 98

The formation of mixed disulfides between proteins and glutathione has been discussed as a potentially interesting metabolic signal. The S-thiolation of proteins with glutathione has been observed in several systems in vitro. We have correlated the increase in glutathione disulfide (GSSG) with the amount of protein mixed disulfides. The methodological aspects are briefly presented; normal values for protSSG are about 20-30 nmol per g wet weight of liver. Several processes have been related to changes in the thiol redox state. The stimulation of flux through the pentose phosphate pathway during the metabolism of t-butyl hydroperoxide is presented, and the increase in cellular activity of glucose-6-phosphate dehydrogenase is correlated with the increase in the level of protSSG. Hormonal stimulation of GSH efflux from the liver by vasopressin or by alpha-adrenergic agonists such as phenylephrine or epinephrine is presented and discussed in relation to physiological states of peripheral (non hepatic) GSH utilization. Preliminary work relates the release of GSH to the perturbations in thiol redox state in inflammation and in exercise.
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PMID:Hormones, glutathione status and protein S-thiolation. 367 5

Studies were conducted to assess the in vitro effects of selected sulfur compounds on the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GSHPX), and glucose-6-phosphate dehydrogenase (G6PDH) in hemolyzates of bovine erythrocytes. All sulfur compounds produced concentration-dependent inhibition in the activities of these enzymes, but their effects on each enzyme were different. SOD and catalase activities were most sensitive to sulfide (S2-), followed by sulfite (SO3(2-)) and sulfate (SO4(2-)). GSHPX activity was most sensitive to SO3(2-), followed by S2-, cysteine and SO4(2-). The activity of G6PDH, however, was maximally inhibited by reduced glutathione (GSH), followed by SO3(2-) and SO4(2-); S2- was inhibitory only at high concentrations. Dialysis of the S2- and SO3(2-)-inhibited enzymes resulted in complete or partial reversal of inhibitory effects. The biochemical significance of these effects in relation to erythrocyte physiology is discussed.
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PMID:Inhibitory effects of various sulfur compounds on the activity of bovine erythrocyte enzymes. 369 7

Cadmium (Cd; 10-100 microM) produced in isolated hepatocytes the formation of thiobarbituric acid-reactants (lipid peroxidation; LPO) and a decrease in SH groups in a time- and concentration-dependent manner. However, glutathione peroxidase (GSH-Px) was not affected indicating that LPO does not originate from GSH-Px injury. In contrast, in presence of Cd a time- and concentration-dependent decrease of glucose-6-phosphate dehydrogenase (G6PDH) and, most strongly, of glutathione reductase (GSSG-R), both members of the GSH-Px system, was observed. These effects could not be inhibited by (+)-cyanidanol-3, a compound known as inhibitor of LPO. Therefore, our data show that Cd-induced LPO is not a function of GSH-Px injury and inhibition of GSSG-R and G6PDH-activity is not a function of LPO. They also indicate that Cd-induced depletion of cellular SH groups are associated with toxic effects of Cd on GSSG-R and G6PDH different from LPO-induction.
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PMID:Consequences of cadmium toxicity in rat hepatocytes: effects of cadmium on the glutathione-peroxidase system. 370 7


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