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)

A virus (MnPV) with the structural characteristics of papilloma viruses was isolated from benign and malignant proliferations of adult animals of the inbred line 'GRA Giessen' of Mastomys natalensis. The particles can be banded in CsCl gradients at densities of 1.34 g/ml (full particles) and 1.29 g/ml (empty particles). The virus DNA has a buoyant density of 1.7104 g/ml and can exist in three different conformations (supercoiled circular, nicked circular and linear), the sedimentation values of which have been determined as 23 to 24S, 16 to 17S and 14 to 15S, respectively. Although the mol. wt. of MnPV DNA is similar to that of HPV 1 DNA, the size of the fragments obtained after cleavage of MnPV DNA with the restriction endonuclease Hae III is quite different from the pattern seen with human papilloma virus. The virion contains 12 different polypeptides; the major structural protein has a mol. wt. of 56 000. MnPV is shown to be the causative agent of the skin proliferations, because tumours can be induced by inoculation of purified virus, whereas no cutaneous alterations are observed when the particles are inoculated in the presence of anti-MnPV serum. MnPV can be re-isolated from the experimentally induced tumours.
J Gen Virol 1978 Nov
PMID:Mastomys natalensis papilloma virus (MnPV), the causative agent of epithelial proliferations: characterization of the virus particle. 21 19

Rhodopseudomonas acidophila strain 10050, grown anaerobically in the light on methanol, contained a methanol and formaldehyde dehydrogenase which could be coupled to phenazine methosulphate; an NAD-linked formaldehyde dehydrogenase which required GSH for activity; and an NAD-linked formate dehydrogenase. The specific activities of these enzymes varied in a non-coordinate manner when the organism was grown on different alcohols, formate or succinate. The affinity of the phenazine methosulphate linked methanol dehydrogenase for methanol was increased 10-fold if the cell-free extract was prepared and assayed in the absence of oxygen. Pulse-labelling experiments with [14C5methanol and [14C]bicarbonate indicated that fixation of carbon dioxide occurred via the ribulose diphosphate cycle and C3 + CO 2 fixation reaction(s). No evidence was obtained for operation of a reduced C1 fixation sequence. This conclusion was borne out by the enzyme content of cell-free extracts of the organism.
J Gen Microbiol 1976 Jun
PMID:Metabolism of methanol by Rhodopseudomonas acidophila. 95 May 54

1. Cerebral ischemia applied for 15 min and followed by a 30 min reperfusion did not change the glutathione (GSH) levels and beta-adrenoceptor density (Bmax) in brain cortex. 2. A significant increase in erythrocyte-lysate GSH concentration (vs control) and a significant decrease of Bmax values in erythrocyte membranes (vs control) was found at the same time. 3. Pretreatment with the alpha-adrenoceptor antagonist phentolamine (5 mg/kg i.p.) prevented the erythrocyte GSH increase but not the decrease of Bmax value. Pretreatment with the beta-antagonist propranolol (2 mg/kg i.p.) did not influence the increase in erythrocyte GSH but circumvented the decrease of Bmax.
Gen Pharmacol 1992 Jan
PMID:Glutathione mobilization during cerebral ischemia and reperfusion in the rat. 131 10

The extent of conversion of supercoiled pBR322 plasmid DNA to the open circular and linear forms can be measured by HPLC on a Waters Gen Pak FAX column following in vitro gamma irradiation of the DNA. This radiation effect has proven to be useful for the study of the radioprotection of DNA by thiols and other drugs. This system was used with gamma irradiation in air at pH 7.0 and physiological ionic strength to compare radioprotection by a series of thiols, disulfides, and thioethers, all having approximately 10(8) s-1 effective hydroxyl radical scavenging rate (10 mm dm-3 drug) and having net charge (Z) ranging from -2 to +3. All sulfur compounds exhibited substantial protection due to scavenging of hydroxyl radicals in bulk solution but thiols exhibited a 24-fold variation in relative ability to protect the plasmid DNA from strand breaks, as assessed from the dose-response curves: mercaptosuccinate (Z = -2), 0.53; GSH (Z = -1), 0.67; 3-mercaptopropionate (Z = -1) 0.80; mercaptoethanol (Z = 0), 1.00; dithiothreitol (Z = 0), 1.5; cysteamine (Z = +1), 3.7; N-(2-mercaptoethyl)-1,3-diaminopropane (WR-1065, Z = +2), 6.7; N1-(2-mercaptoethyl)spermidine (WR-35980, Z = +3), 12. Comparison of these results with those obtained using disulfide and thioether radioprotectors indicated that local scavenging of hydroxyl radicals near DNA increases slightly with Z, apparently as a result of variations in thiol concentration near DNA, but this accounts for only a small fraction of the change with Z found for cationic thiols. The marked increase in protection found for cationic thiols was attributed to chemical repair of DNA radicals and was in accord with predictions based upon recently measured rates for chemical repair of DNA radicals and was in accord with predictions based upon recently measured rates for chemical repair of pBR322 radicals. It is concluded that chemical repair of DNA radicals by anionic thiols does not compete with the oxygen fixation reaction in air and that protection by these thiols occurs primarily via the scavenging of hydroxyl radicals. However, chemical repair of DNA radicals is significantly enhanced by counterion condensation for cationic thiols and becomes a significant factor in their ability to protect DNA against radiation damage under aerobic conditions.
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PMID:Aerobic radioprotection of pBR322 by thiols: effect of thiol net charge upon scavenging of hydroxyl radicals and repair of DNA radicals. 157 74

Glutathione-deficient mutants (gshA) of the yeast Saccharomyces cerevisiae, impaired in the first step of glutathione (GSH) biosynthesis were studied with respect to the regulation of enzymes involved in GSH catabolism and cysteine biosynthesis. Striking differences were observed in the content of the sulphur amino acids when gshA mutants were compared to wild-type strains growing on the same minimal medium. Furthermore, all mutants examined showed a derepression of gamma-glutamyltranspeptidase (gamm-GT), the enzyme initiating GSH degradation. However, gamma-cystathionase and cysteine synthase were unaffected by the GSH deficiency as long as the nutrient sulphate source was not exhausted. The results suggest that the mutants are probably not impaired in the sulphate assimilation pathway, but that the gamma-glutamyl cycle could play a leading role in the regulation of the sulphur fluxes. Studies of enzyme regulation showed that the derepression of gamma-GT observed in the gshA strains was most probably due to an alteration of the thiol status. The effectors governing the biosynthesis of cysteine synthase and gamma-cystathionase seemed different from those playing a role in gamma-GT regulation and it was only under conditions of total sulphate deprivation that all these enzymes were derepressed. As a consequence the endogenous pool of GSH was used in the synthesis of cysteine. GSH might, therefore, fulfil the role of a storage compound.
J Gen Microbiol 1991 Mar
PMID:Glutathione as an endogenous sulphur source in the yeast Saccharomyces cerevisiae. 167 26

The concentration of the tripeptide glutathione (GSH) was measured in primary cultures of neurons and astroglial cells from rat cerebral cortex and brain stem. The concentration of GSH was found to be approximately 20 nmol/mg protein in the neuronal culture from the cerebral cortex and ca. 40 nmol/mg protein in the neuronal brain stem cultures. A GSH concentration of approximately 20 nmol/mg was observed in the astrocyte cultures from both brain regions. The possibility to increase the GSH concentration was tested by incubating the cultures in the presence of the GSH precursor gamma-glutamylcysteine (gamma-GC). In the cultured astrocytes gamma-GC produced a dose-dependent increase in GSH. A similar increase was observed in the neuronal cultures, but this effect failed to reach statistical significance.
J Neural Transm Gen Sect 1991
PMID:The presence of glutathione in primary neuronal and astroglial cultures from rat cerebral cortex and brain stem. 175 Oct 28

1. Cyanide inhibited the uptake of vitamin C by human polymorphonuclear leukocytes (PMNs). 2. Preincubation of PMNs with cyanide had no effect on cytochalasin B-inhibitable uptake of dehydroascorbic acid (DHA) (the reversibly oxidized and transportable form of vitamin C). 3. Preincubation of DHA with cyanide resulted in inhibition of DHA uptake. 4. Vitamin C uptake was decreased by cyanide to the same degree as it was by glutathione (GSH), which effectively reduces DHA to ascorbic acid. The effects of cyanide and GSH were not additive. 5. The data are consistent with the hypothesis that cyanide inhibition of vitamin C uptake represents the chemical elimination of extracellular DHA rather than the inhibition of active transport in these cells.
Gen Pharmacol 1991
PMID:The effect of cyanide on vitamin C uptake by human polymorphonuclear leukocytes. 176 Nov 96

1. The effects of treatment with the antischistosomal drug oltipraz on reduced glutathione (GSH), lipid peroxide (LP) and ascorbic acid (AA) concentrations in the liver, kidney and brain were studied in mice 24 h after drug administration. 2. The influence of pretreatment with cysteine or olive oil on the above variables in oltipraz-treated mice was also investigated. 3. Oltipraz, at single oral doses of 25 and 125 mg/kg, did not affect significantly the concentrations of GSH, LP or AA in any of the tissues studied. 4. At a dose of 625 mg/kg, the drug produced significant increases in GSH concentration in the liver (about 34%), kidney (38%) and brain (24%). 5. AA concentrations were not significantly affected by the drug treatment in any of the organs studied. 6. However lipid peroxide formation in the liver of mice treated with oltipraz (625 mg/kg) was less than that in control animals by about 45% (P less than 0.05). 7. In other organs it was not significantly affected by the treatment. 8. Oltipraz (625 mg/kg) was given orally to mice which were pretreated with cysteine (25, 50 and 100 mg/kg for 7 days intramuscularly). 9. The cysteine pretreatments did not affect significantly the increases in GSH caused by oltipraz alone, although they were effective in significantly increasing GSH concentrations in saline-treated mice. 10. The oltipraz-induced increases in the concentrations of GSH in liver and kidney was enhanced (by about 16%) by olive oil (0.2, 02 and 0.4 ml/mouse) when given 1 h before oltipraz treatment. 11. Concentrations of LP and AA were not significantly affected by olive oil pretreatment.
Gen Pharmacol 1991
PMID:Lipid peroxidation, glutathione and ascorbic acid concentrations in tissues of mice treated with oltipraz: influence of cysteine and olive oil pretreatments. 176 Dec 1

1. Elastin peptides (kappa-elastin) prepared by alcoholic potassium hydroxide degradation of insoluble elastin were shown to increase the activities of antioxidant enzymes (SOD, CAT, GSH-Px) and the lipid peroxide concentration within fibroblasts. 2. The preincubation of cells with nifedipine (calcium channel antagonist) and trifluoperazine (calmodulin antagonist) caused the decrease in the activities of studied enzymes and the concentration of TBA-reactive products in fibroblasts stimulated with kappa-elastin. 3. The preincubation with ketotifen (antiallergic drug) has no effect on the activities of SOD, CAT, GSH-Px and the lipid peroxide concentration in stimulated cells. 4. These data suggest the possibilities of pharmacological modulation of the biological effects induced by elastin-derived peptides.
Gen Pharmacol 1991
PMID:Pharmacological modulation of the antioxidant enzymes activities and the concentration of peroxidation products in fibroblasts stimulated with elastin peptides. 186 23

The GSH-binding site of glutathione S-transferase (GST) isoenzymes was studied by investigating their substrate-specificity for three series of GSH analogues; further, a model of the interactions of GSH with the G-site is proposed. Twelve glycyl-modified GSH analogues, four ester derivatives of GSH and three cysteinyl-modified GSH analogues were synthesized and tested with purified forms of rat liver GST (1-1, 2-2, 3-3 and 4-4). The glycyl analogues exhibited spontaneous chemical reaction rates with 1-chloro-2,4-dinitrobenzene comparable with the GSH rate. In contrast, the enzymic rates (Vmax.) differed greatly, from less than 1 up to 140 mumol/min per mg; apparently, a reaction mechanism is followed that is very sensitive to substitutions at the glycyl domain. No correlation exists between the chemical rates and Vmax. values for the analogues. Analogues of GSH in which L-cysteine was replaced by D-cysteine, L-homocysteine or L-penicillamine showed little or no capacity to replace GSH as co-substrate for the GSTs. GSH monomethyl and monoethyl esters showed Vmax. values greater than the Vmax. measured with GSH: the Vmax. for the monoethyl ester of GSH and GST 3-3 was 5-fold that for GSH. The data obtained in this and previous studies [Adang, Brussee, Meyer, Coles, Ketterer, van der Gen & Mulder (1988) Biochem. J. 255, 721-724; Adang, Meyer, Brussee, van der Gen, Ketterer & Mulder (1989) Biochem. J. 264, 759-764] allow a model of the interactions of GSH in the G-site in GSTs to be postulated. The gamma-glutamyl site is the main binding determinant: the alpha-carboxylate group is obligatory, whereas shifting of the amino group and shortening of the peptide backbone only decreased kcat./Km. Furthermore, the GSTs appear to be very critical with respect to a correct orientation of the thiol group of the GSH analogue. The glycyl site is the least restrictive domain in the G-site of GSTs: amino acid analogues all showed Km values between 0.2 and 0.6 mM (that for GSH is 0.2-0.3 mM), but large differences in Vmax. exist. The glycyl carboxylate group is not essential for substrate recognition, since decarboxy analogues and ester derivatives showed high activities. The possible mechanisms for an increased Vmax. in some analogues are briefly discussed.
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PMID:The glutathione-binding site in glutathione S-transferases. Investigation of the cysteinyl, glycyl and gamma-glutamyl domains. 237 57


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