Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “GLUTATHIONE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources
PubMed1992

Transfection with gamma-glutamyl transpeptidase enhances recovery from glutathione depletion using extracellular glutathione.

Glutathione (L-gamma-glutamyl-L-cysteinylglycine) is an important constituent of the antioxidant and detoxifying mechanisms of cells. The plasma membrane bound enzyme, gamma-glutamyl transpeptidase (GGT), catalyzes the first step in the degradation of extracellular glutathione, the components of which are then used for de novo glutathione synthesis. We tested the hypothesis that an increase in GGT activity would enhance the utilization of extracellular glutathione by cells challenged with a glutathione-depleting agent. A eukaryotic system stably overexpressing GGT (nearly 200-fold) was developed by transfection of NIH-3T3 fibroblasts with a human placental GGT cDNA. These cells and controls were incubated for 30 min with 1 mM diethyl maleate, which caused approximately 80% intracellular glutathione depletion. Glutathione was added to the medium and cells were allowed to resynthesize intracellular glutathione. The transfected cells used extracellular glutathione much more efficiently than controls in terms of both the concentration dependence and the rate of glutathione resynthesis. Serine-borate, a competitive inhibitor of GGT, blocked the restoration of intracellular glutathione. The results support the hypothesis that the increase in GGT activity that occurs in some toxicologic or pathologic conditions could provide protection against glutathione depletion.

Animals↗
PubMed1989

Mitochondrial damage in muscle occurs after marked depletion of glutathione and is prevented by giving glutathione monoester.

Skeletal muscle degeneration associated with mitochondrial damage was found after marked depletion of glutathione produced by administration to mice of buthionine sulfoximine, an irreversible inhibitor of gamma-glutamylcysteine synthetase. No mitochondrial damage was found in heart. These studies show that in the absence of applied stress (such as ischemia, drug toxicity), very marked depletion (to approximately 3% of the controls) of glutathione must occur before skeletal muscle mitochondria are affected and thus suggest that muscle has a large excess of glutathione. Depletion of glutathione followed a biphasic pattern in skeletal muscle and heart, probably reflecting, in the slow phase, loss of glutathione from mitochondria. Skeletal muscle degeneration did not occur when glutathione monoisopropyl ester was given together with buthionine sulfoximine; it did occur, however, when glutathione was given together with buthionine sulfoximine. Administration of the glutathione monoester (but not of glutathione) prevented the marked decline of mitochondrial glutathione produced by buthionine sulfoximine in skeletal muscle and increased the level of glutathione in heart mitochondria to values higher than the controls. The findings suggest that glutathione monoesters may be useful agents for protection of heart and skeletal muscle against toxicity.

Animals↗
PubMed1993

Correction of glutathione deficiency in the lower respiratory tract of HIV seropositive individuals by glutathione aerosol treatment.

BACKGROUND: Concentrations of glutathione, a ubiquitous tripeptide with immune enhancing and antioxidant properties, are decreased in the blood and lung epithelial lining fluid of human immunodeficiency virus (HIV) seropositive individuals. Since the lung is the most common site of infection in those who progress to AIDS it is rational to consider whether it is possible to safely augment glutathione levels in the epithelial lining fluid of HIV seropositive individuals, thus potentially improving local host defence. METHODS: Purified reduced glutathione was delivered by aerosol to HIV seropositive individuals (n = 14) and the glutathione levels in lung epithelial lining fluid were compared before and at one, two, and three hours after aerosol administration. RESULTS: Before treatment total glutathione concentrations in the epithelial lining fluid were approximately 60% of controls. After three days of twice daily doses each of 600 mg reduced glutathione, total glutathione levels in the epithelial lining fluid increased and remained in the normal range for at least three hours after treatment. Strikingly, even though > 95% of the glutathione in the aerosol was in its reduced form, the percentage of oxidised glutathione in epithelial lining fluid increased from 5% before treatment to about 40% three hours after treatment, probably reflecting the use of glutathione as an antioxidant in vivo. No adverse effects were observed. CONCLUSIONS: It is feasible and safe to use aerosolised reduced glutathione to augment the deficient glutathione levels of the lower respiratory tract of HIV seropositive individuals. It is rational to evaluate further the efficacy of this tripeptide in improving host defence in HIV seropositive individuals.

Adult↗
PubMed1985

Uptake of the glutathione conjugate S-(1,2-dichlorovinyl)glutathione by renal basal-lateral membrane vesicles and isolated kidney cells.

Transport of the glutathione S-conjugate, S-(1,2-dichlorovinyl)glutathione (DCVG), was studied in renal basal-lateral membrane vesicles and isolated rat kidney cells. The time course of S-(1,2-dichlorovinyl)glutathione uptake in membrane vesicles exhibited an overshoot in the presence of sodium, indicating transport against a concentration gradient. The initial rate of uptake with membrane potential clamped at 0 mV was stimulated 2.5-fold by an inwardly directed gradient of 100 mM sodium chloride. Hyperpolarization of the membrane potential to -60 mV in the presence of sodium stimulated uptake another 2.7-fold, indicating that cotransport of sodium and S-(1,2-dichlorovinyl)glutathione is electrogenic. Sodium-dependent DCVG uptake was inhibited by glutathione, glutathione disulfide, and gamma-glutamylglutamate, but not by the corresponding cysteine S-conjugate, S-(1,2-dichlorovinyl)cysteine, indicating that the transport system is specific for the gamma-glutamyl moiety. Probenecid was also a potent inhibitor of sodium-dependent uptake. S-(1,2-dichlorovinyl)glutathione inhibited sodium-dependent uptake of glutathione in a concentration-dependent manner. Thus, these results show that uptake of DCVG and glutathione is mediated by the same sodium-coupled system. Uptake of S-(1,2-dichlorovinyl)glutathione was also demonstrated in isolated kidney cells; in the presence of sodium, cells accumulated approximately 4-fold more DCVG than in the absence of sodium. This basal-lateral membrane transport system can enable efficient delivery of circulating S-(1,2-dichlorovinyl)glutathione to kidney cells and may, therefore, contribute to its potent and selective nephrotoxicity. In addition, it suggests that renal clearance of glutathione conjugates may include transport from the blood through epithelial cells into the lumen as well as direct filtration through the glomerulus.

Animals↗
PubMedDate not supplied

Effects of glutathione isopropyl ester on bile flow in glutathione-depleted rats.

Combined administration of buthionine sulfoximine (2.5 mmol/kg, i.p.) and diethyl maleate (1.0 ml/kg, i.p.) resulted in a near-complete depletion of hepatic glutathione (0.02 mumol/g liver vs 5.17 mumol/g in saline-treated controls) in male Sprague-Dawley rats. Bile flow was markedly reduced in the rats as compared with the controls and glutathione was not detected in the bile. The linear regression of the correlation between bile flow and endogenous bile-acid excretion rates revealed that no bile acid-independent bile flow was produced in the glutathione-depleted rats. The bile flow was partially restored by an intravenous infusion of glutathione isopropyl ester (1.17 mmol/kg/hr). Glutathione levels were increased in the bile (16 nmol/kg/min) and in the liver (0.55 mumol/g) at the end of the 100 min infusion period of the ester. The increments in bile flow rates were not proportional to the biliary excretion rates of bile acids or glutathione, and the flow rates suddenly increased when glutathione levels in the bile reached an apparent threshold. The increments, not accompanied with an excretion of diethyl maleate-glutathione conjugate, were much greater than expected from the osmotic choleresis of glutathione in the bile. These results indicate that hepatic glutathione above a certain level is required for the formation of a portion of bile flow, and that an intravenous administration of glutathione isopropyl ester is effective in partially restoring the bile formation impaired by glutathione depletion.

Animals↗
PubMed1999

Synthesis of the antioxidant glutathione in neurons: supply by astrocytes of CysGly as precursor for neuronal glutathione.

Deficiency of the antioxidant glutathione in brain appears to be connected with several diseases characterized by neuronal loss. To study neuronal glutathione metabolism and metabolic interactions between neurons and astrocytes in this respect, neuron-rich primary cultures and transient cocultures of neurons and astroglial cells were used. Coincubation of neurons with astroglial cells resulted within 24 hr of incubation in a neuronal glutathione content twice that of neurons incubated in the absence of astroglial cells. In cultured neurons, the availability of cysteine limited the cellular level of glutathione. During a 4 hr incubation in a minimal medium lacking all amino acids except cysteine, the amount of neuronal glutathione was doubled. Besides cysteine, also the dipeptides CysGly and gammaGluCys were able to serve as glutathione precursors and caused a concentration-dependent increase in glutathione content. Concentrations giving half-maximal effects were 5, 5, and 200 microM for cysteine, CysGly, and gammaGluCys, respectively. In the transient cocultures, the astroglia-mediated increase in neuronal glutathione was suppressed by acivicin, an inhibitor of the astroglial ectoenzyme gamma-glutamyl transpeptidase, which generates CysGly from glutathione. These data suggest the following metabolic interaction in glutathione metabolism of brain cells: the ectoenzyme gamma-glutamyl transpeptidase uses as substrate the glutathione released by astrocytes to generate the dipeptide CysGly that is subsequently used by neurons as precursor for glutathione synthesis.

Animals↗
PubMed1995

Analysis of glutathione, glutathione disulfide, cysteine, homocysteine, and other biological thiols by high-performance liquid chromatography following derivatization by n-(1-pyrenyl)maleimide.

The compound N-(1-pyrenyl)maleimide (NPM) reacts with free sulfhydryl groups to form fluorescent derivatives. A new method for measurement of glutathione and other biological thiols utilizing reverse-phase high-performance liquid chromatography to separate and quantify these derivatives is described. Separation and quantification of glutathione, cysteine, homocysteine, cysteinylglycine, and gamma-glutamylcysteine derivatives are achieved. The method allows for the measurement of glutathione disulfide by masking free glutathione with 2-vinylpyridine, reducing glutathione disulfide with glutathione reductase, and measuring the resulting glutathione. Coefficient of variations for the various thiols measured by the NPM method range from 1.5 to 8.8%. The lower detection limit is around 50 fmol of glutathione. NPM derivatives are shown to be stable for 2 months at 4 degrees C. Between 94.2 and 97.2% of glutathione and/or glutathione disulfide added to a sample is recovered using the NPM method. The NPM method is compared to the monobromobimane high-performance liquid chromatography method and the Tietze assay by measuring glutathione in homogenates from five different cell lines. The newly developed method offers some advantages over the currently accepted techniques, including specificity, speed, sensitivity, and ease of use.

Animals↗
PubMed1999

Analysis of glutathione and glutathione disulfide in whole cells and mitochondria by postcolumn derivatization high-performance liquid chromatography with ortho-phthalaldehyde.

A method is described for the detection of glutathione (GSH) and glutathione disulfide (GSSG) based on a HPLC postcolumn reaction with ortho-phthalaldehyde (OPT) at pH 12 followed by fluorescence detection. Although similar methods have been reported, the high pH of the postcolumn reaction adds considerable selectivity and sensitivity to the measurement of GSH and glutathione disulfide. The limit of detection approaches 100 fmol, which is sufficient to detect whole-cell glutathione disulfide in 10,000 cells or mitochondrial glutathione disulfide in 20 million cells. Using this method, glutathione and glutathione disulfide were measured in human lymphocytes, granulocytes, and cultured Jurkat T cells, as well as in the corresponding samples of mitochondria. The percentage of glutathione disulfide to total glutathione in whole-cell extracts was approximately 1%. In contrast, the percentage was relatively high in mitochondria, with the mitochondria of granulocytes having the highest (25%) followed by those of lymphocytes (15%) and finally by cultured Jurkat T cells (9%). This method extends the analysis of glutathione and glutathione disulfide to mitochondria obtained from a relatively small number of cells.

Chromatography, High Pressure Liquid↗
PubMed1997

Glutathione, glutathione S-transferase alpha and pi, and aldehyde dehydrogenase content in relationship to drug resistance in ovarian cancer.

Glutathione, glutathione S-transferases alpha and pi, and aldehyde dehydrogenase are associated with resistance to carboplatin and/or cyclophosphamide in cell lines. Therefore, we examined whether the expression of these factors in ovarian cancer tissue specimens is associated with resistance of the patients to combination chemotherapy with cyclophosphamide/carboplatin. Ovarian cancer tissue specimens were taken intraoperatively from 139 patients and frozen in liquid nitrogen, and the contents of glutathione S-transferases alpha and pi, total glutathione, and aldehyde dehydrogenase activity were determined. No association between the levels of glutathione S-transferases alpha and pi or aldehyde dehydrogenase activity in tumor tissue and the survival time was observed in patients with primary ovarian cancer. Significantly higher levels of aldehyde dehydrogenase were observed in FIGO stage I and II compared to FIGO stage III and IV tumors (P = 0.019, Wilcoxon test, two sided). The median survival time was significantly longer in patients with primary ovarian cancer with a tumor glutathione content of <4.9 microg/mg protein compared to patients with a tumor glutathione content of > or =4.9 microg/mg protein (P = 0.047). However, glutathione was not an independent prognostic factor, but was significantly associated with FIGO stage resulting in higher levels in FIGO stage III and IV tumors than in FIGO stage I and II tumors (P = 0.0094, Wilcoxon test, two sided). In conclusion the glutathione content was associated with progression of ovarian carcinomas but neither glutathione nor glutathione S-transferases alpha and pi or aldehyde dehydrogenase were independent factors of resistance to cyclophosphamide/carboplatin.

Aldehyde Dehydrogenase↗
PubMed1998

Rhythms of glutathione peroxidase and glutathione reductase in brain of chick and their inhibition by light.

Melatonin was recently shown to be a component of the antioxidative defense system of organisms due to its free radical scavenging and antioxidant activities. Pharmacologically, melatonin stimulates the activity of the peroxide detoxifying enzyme glutathione peroxidase in rat brain and in several tissues of chicks. In this report, we studied the endogenous rhythm of two antioxidant enzymes, glutathione peroxidase and glutathione reductase, in five regions (hippocampus, hypothalamus, striatum, cortex and cerebellum) of chick brain and correlated them with physiological blood melatonin concentrations. Glutathione peroxidase exhibited a marked 24 h rhythm with peak activity in each brain region which had acrophases about 8 h after lights off and about 4 h after the serum melatonin peak was detected. Glutathione reductase activity exhibited similar robust rhythms with the peaks occurring roughly 2 h after those of glutathione peroxidase. We suggest that neural glutathione peroxidase increases due to the rise of nocturnal melatonin levels while glutathione reductase activity rises slightly later possibly due to an increase of its substrate, oxidized glutathione. The exposure of chicks to constant light for 6 days eliminated the melatonin rhythm as well as the peaks in both glutathione peroxidase and glutathione reductase activities. These findings suggest that the melatonin rhythm may be related to the nighttime increases in the enzyme activities, although other explanations cannot be excluded.

Animals↗
PubMed1991

Stereochemistry of the microsomal glutathione S-transferase catalyzed addition of glutathione to chlorotrifluoroethene.

The stereochemistry of S-(2-chloro-1,1,2-trifluoroethyl)glutathione formation was studied in rat liver cytosol, microsomes, N-ethylmaleimide-treated microsomes, 9000g supernatant fractions, purified rat liver microsomal glutathione S-transferase, and isolated rat hepatocytes. The absolute configuration of the chiral center generated by the addition of glutathione to chlorotrifluoroethene was determined by degradation of S-(2-chloro-1,1,2-trifluoroethyl)glutathione to chlorofluoroacetic acid, followed by derivatization to form the diastereomeric amides N-(S)-alpha-methylbenzyl-(S)-chlorofluoacetamide and N-(S)-alpha-methylbenzyl-(R)-chlorofluoroacetamide, which were separated by gas chromatography. Native and N-ethylmaleimide-treated rat liver microsomes, purified rat liver microsomal glutathione S-transferase, rat liver 9000g supernatant, and isolated rat hepatocytes catalyzed the formation of 75-81% (2S)-S-(2-chloro-1,1,2-trifluoroethyl)glutathione; rat liver cytosol catalyzed the formation of equal amounts of (2R)- and (2S)-S-(2-chloro-1,1,2-trifluoroethyl)glutathione. In rat hepatocytes, microsomal glutathione S-transferase catalyzed the formation of 83% of the total S-(2-chloro-1,1,2-trifluoroethyl)glutathione formed. These observations show that the microsomal glutathione S-transferase catalyzes the first step in the intracellular, glutathione-dependent bioactivation of the nephrotoxin chlorotrifluoroethene.

Animals↗
PubMed2001

Characterization of glutathione amide reductase from Chromatium gracile. Identification of a novel thiol peroxidase (Prx/Grx) fueled by glutathione amide redox cycling.

Among the Chromatiaceae, the glutathione derivative gamma-l-glutamyl-l-cysteinylglycine amide, or glutathione amide, was reported to be present in facultative aerobic as well as in strictly anaerobic species. The gene (garB) encoding the central enzyme in glutathione amide cycling, glutathione amide reductase (GAR), has been isolated from Chromatium gracile, and its genomic organization has been examined. The garB gene is immediately preceded by an open reading frame encoding a novel 27.5-kDa chimeric enzyme composed of one N-terminal peroxiredoxin-like domain followed by a glutaredoxin-like C terminus. The 27.5-kDa enzyme was established in vitro to be a glutathione amide-dependent peroxidase, being the first example of a prokaryotic low molecular mass thiol-dependent peroxidase. Amino acid sequence alignment of GAR with the functionally homologous glutathione and trypanothione reductases emphasizes the conservation of the catalytically important redox-active disulfide and of regions involved in binding the FAD prosthetic group and the substrates glutathione amide disulfide and NADH. By establishing Michaelis constants of 97 and 13.2 microm for glutathione amide disulfide and NADH, respectively (in contrast to K(m) values of 6.9 mm for glutathione disulfide and 1.98 mm for NADPH), the exclusive substrate specificities of GAR have been documented. Specificity for the amidated disulfide cofactor partly can be explained by the substitution of Arg-37, shown by x-ray crystallographic data of the human glutathione reductase to hydrogen-bond one of the glutathione glycyl carboxylates, by the negatively charged Glu-21. On the other hand, the preference for the unusual electron donor, to some extent, has to rely on the substitution of the basic residues Arg-218, His-219, and Arg-224, which have been shown to interact in the human enzyme with the NADPH 2'-phosphate group, by Leu-197, Glu-198, and Phe-203. We suggest GAR to be the newest member of the class I flavoprotein disulfide reductase family of oxidoreductases.

Amino Acid Sequence↗
PubMed1996

A glutathione reductase mutant of yeast accumulates high levels of oxidized glutathione and requires thioredoxin for growth.

A glutathione reductase null mutant of Saccharomyces cerevisiae was isolated in a synthetic lethal genetic screen for mutations which confer a requirement for thioredoxin. Yeast mutants that lack glutathione reductase (glr1 delta) accumulate high levels of oxidized glutathione and have a twofold increase in total glutathione. The disulfide form of glutathione increases 200-fold and represents 63% of the total glutathione in a glr1 delta mutant compared with only 6% in wild type. High levels of oxidized glutathione are also observed in a trx1 delta, trx2 delta double mutant (22% of total), in a glr1 delta, trx1 delta double mutant (71% of total), and in a glr1 delta, trx2 delta double mutant (69% of total). Despite the exceptionally high ratio of oxidized/reduced glutathione, the glr1 delta mutant grows with a normal cell cycle. However, either one of the two thioredoxins is essential for growth. Cells lacking both thioredoxins and glutathione reductase are not viable under aerobic conditions and grow poorly anaerobically. In addition, the glr1 delta mutant shows increased sensitivity to the thiol oxidant diamide. The sensitivity to diamide was suppressed by deletion of the TRX2 gene. The genetic analysis of thioredoxin and glutathione reductase in yeast runs counter to previous studies in Escherichia coli and for the first time links thioredoxin with the redox state of glutathione in vivo.

Diamide↗
PubMed1983

Decomposition of hydroperoxides derived from microsomes or lipoprotein by glutathione peroxidase and glutathione S-transferase.

Protective effects of glutathione peroxidase, glutathione S-transferase purified from human liver and superoxide dismutase against lipid peroxidation were investigated. In the presence of glutathione, lipid hydroperoxides found in microsomal membrane were decomposed by glutathione peroxidase and cationic glutathione S-transferase, but anionic glutathione S-transferase had no effect on them. Superoxide dismutase exhibited antioxidation effect by preventing accumulation of lipid hydroperoxides. Serum lipid hydroperoxides existing in low density lipoprotein fraction were also decomposed by glutathione peroxidase and cationic glutathione S-transferase. These findings suggest that the hydroperoxide level, which has high toxicity, could be controlled by these glutathione-dependent glutathione peroxidase and cationic glutathione S-transferase.

Animals↗
PubMed1988

Comparison of glutathione S-transferase activity between drug-resistant and -sensitive human tumor cells: is glutathione S-transferase associated with multidrug resistance?

We have studied the levels of glutathione S-transferase in drug-resistant and -sensitive human tumor cell lines to examine a possible involvement of glutathione S-transferase (GST) in multidrug resistance mechanisms. No increase in the activity of glutathione S-transferase was detected in myelogenous leukemia K562 resistant to adriamycin (K562/ADM), ovarian carcinoma cell line A2780 resistant to adriamycin (2780AD), or acute lymphoblastic leukemia cell line CCRF-CEM resistant to vinblastine (CEM-VLB100), compared with the drug-sensitive parent tumor cells. The human breast cancer cell lines Hattori and MCF-7 had a 12- to 63-fold lower level of glutathione S-transferase activity than K562, A2780, CCRF-CEM, and their drug-resistant sublines. Induction of ADM resistance in Hattori did not increase the activity of glutathione S-transferase. However, induction of colchicine resistance in MCF-7 resulted in a 70-fold increase in the activity of glutathione S-transferase. A revertant of the colchicine-resistant MCF-7 contained a level of glutathione S-transferase activity similar to that of the resistant subline. The increase of glutathione S-transferase activity did not alter the sensitivity of the cell to cytotoxic drugs. The increased activity was due to the appearance of glutathione S-transferase pi, as shown by enzyme inhibition using anti-glutathione S-transferase pi antibody. Our findings indicate that increased cellular glutathione S-transferase activity is not associated with the development of multidrug resistance.

Antineoplastic Agents↗
PubMed1985

Glutathione monoethyl ester: preparation, uptake by tissues, and conversion to glutathione.

Glutathione monoethyl ester (L-gamma-glutamyl-L-cysteinylglycyl ethyl ester), in contrast to glutathione itself, is effectively transported into many types of cells. The ester is converted intracellularly into glutathione. Intraperitoneal injection of 35S-labeled ester into mice was followed by rapid appearance of isotope in the glutathione of liver, kidney, spleen, pancreas, and heart; the glutathione levels of these tissues also increased. Oral administration of the ester to mice also increased cellular glutathione levels. Relatively little extracellular deesterification was found. Transport of glutathione ester into human erythrocytes and intracellular conversion to glutathione was observed. The findings suggest that the glutathione ester will be useful as a radioprotecting agent and in the prevention and treatment of toxicity due to certain foreign compounds and oxygen. The ester may be useful in experimental work on glutathione transport, metabolism, and function, and in related studies on oxygen toxicity, radiation, mutagenesis, and ageing. Methods for the preparation of glutathione monoethyl ester and several related compounds are given.

Administration, Oral↗
PubMed1986

The formation of styrene glutathione adducts catalyzed by prostaglandin H synthase. A possible new mechanism for the formation of glutathione conjugates.

The metabolism of styrene by prostaglandin hydroperoxidase and horseradish peroxidase was examined. Ram seminal vesicle microsomes in the presence of arachidonic acid or hydrogen peroxide and glutathione converted styrene to glutathione adducts. Neither styrene 7,8-oxide nor styrene glycol was detected as a product in the incubation. Also, the addition of styrene 7,8-oxide and glutathione to ram seminal vesicle microsomes did not yield styrene glutathione adducts. The peroxidase-generated styrene glutathione adducts were isolated by high pressure liquid chromatography and characterized by NMR and tandem mass spectrometry as a mixture of (2R)- and (2S)-S-(2-phenyl-2-hydroxyethyl)glutathione. (1R)- and (1S)-S-(1-phenyl-2-hydroxyethyl)glutathione were not formed by the peroxidase system. The addition of phenol or aminopyrine to incubations, which greatly enhances the oxidation of glutathione to a thiyl radical by peroxidases, increased the formation of styrene glutathione adducts. We propose a new mechanism for the formation of glutathione adducts that is independent of epoxide formation but dependent on the initial oxidation of glutathione to a thiyl radical by the peroxidase, and the subsequent reaction of the thiyl radical with a suitable substrate, such as styrene.

Animals↗
PubMed1984

Changes in glutathione and glutathione metabolizing enzymes in erythrocytes and lymphocytes of mice as a function of age.

Changes in reduced glutathione levels in liver, lung and whole blood of female Swiss-Webster mice with age were determined. In addition, glutathione content, and glutathione S-transferase and glutathione reductase activities of erythrocytes and lymphocytes of mice as a function of age were examined. Reduced glutathione content increased in liver, lung, whole blood, erythrocytes and lymphocytes with age from 3 to 9 months, reached a maximum level at 9 months of age and decreased thereafter with advanced age in all tissues. Glutathione S-transferase and glutathione reductase activities in erythrocytes and lymphocytes increased with age from 3 to 9 months, reached maximum activities at 9 months and decreased thereafter with advanced age. The glutathione content of erythrocytes from animals 18 months of age decreased by 56% as compared to 9 month old mice, while the activities of glutathione S-transferase and glutathione reductase decreased by 56 and 48%, respectively, over the same age span.

Aging↗