scholarly journals Two immunologically distinct Yc-type subunits are present in rat lung glutathione S-transferases

1984 ◽  
Vol 224 (1) ◽  
pp. 335-338 ◽  
Author(s):  
S V Singh ◽  
Y C Awasthi
Keyword(s):  
Glutathione Peroxidase ◽  
Rat Liver ◽  
Peroxidase Activity ◽  
Gel Electrophoresis ◽  
Rat Lung ◽  
Glutathione Peroxidase Activity ◽  
Glutathione S Transferase ◽  
Two Dimensional Gel Electrophoresis ◽  
Glutathione S Transferases

Two types of 25 000-Mr subunits are present in rat lung glutathione S-transferase I (pI 8.8). These subunits, designated Yc and Yc', are immunologically and functionally distinct from each other. The homodimers YcYc (pI 10.4) and Yc'Yc' (pI 7.6) obtained by hybridization in vitro of the two subunits of glutathione S-transferase I (pI 8.8) were isolated and characterized. Results of these studies indicate that only the Yc subunits express glutathione peroxidase activity and cross-react with the antibodies raised against glutathione S-transferase B (YaYc) or rat liver. The Yc' subunits do not express glutathione peroxidase activity and do not cross-react with the antibodies raised against glutathione S-transferase B of rat liver. The amino acid compositions of these two subunits are also different. These two subunits can also be separated by the two-dimensional gel electrophoresis of glutathione S-transferase I (pI 8.8) of rat lung.

scholarly journals The distribution, induction and isoenzyme profile of glutathione S-transferase and glutathione peroxidase in isolated rat liver parenchymal, Kupffer and endothelial cells

1989 ◽  
Vol 264 (3) ◽  
pp. 737-744 ◽  
Author(s):  
P Steinberg ◽  
H Schramm ◽  
L Schladt ◽  
L W Robertson ◽  
H Thomas ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Glutathione Peroxidase ◽  
Rat Liver ◽  
Peroxidase Activity ◽  
Cell Types ◽  
Transferase Activity ◽  
Glutathione Peroxidase Activity ◽  
Glutathione S Transferase ◽  
Liver Parenchymal ◽  
Parenchymal Cells

The distribution and inducibility of cytosolic glutathione S-transferase (EC 2.5.1.18) and glutathione peroxidase (EC 1.11.1.19) activities in rat liver parenchymal, Kupffer and endothelial cells were studied. In untreated rats glutathione S-transferase activity with 1-chloro-2,4-dinitrobenzene and 4-hydroxynon-2-trans-enal as substrates was 1.7-2.2-fold higher in parenchymal cells than in Kupffer and endothelial cells, whereas total, selenium-dependent and non-selenium-dependent glutathione peroxidase activities were similar in all three cell types. Glutathione S-transferase isoenzymes in parenchymal and non-parenchymal cells isolated from untreated rats were separated by chromatofocusing in an f.p.l.c. system: all glutathione S-transferase isoenzymes observed in the sinusoidal lining cells were also detected in the parenchymal cells, whereas Kupffer and endothelial cells lacked several glutathione S-transferase isoenzymes present in parenchymal cells. At 5 days after administration of Arocolor 1254 glutathione S-transferase activity was only enhanced in parenchymal cells; furthermore, selenium-dependent glutathione peroxidase activity decreased in parenchymal and non-parenchymal cells. At 13 days after a single injection of Aroclor 1254 a strong induction of glutathione S-transferase had taken place in all three cell types, whereas selenium-dependent glutathione peroxidase activity remained unchanged (endothelial cells) or was depressed (parenchymal and Kupffer cells). Hence these results clearly establish that glutathione S-transferase and glutathione peroxidase are differentially regulated in rat liver parenchymal as well as non-parenchymal cells. The presence of glutathione peroxidase and several glutathione S-transferase isoenzymes capable of detoxifying a variety of compounds in Kupffer and endothelial cells might be crucial to protect the liver from damage by potentially hepatotoxic substances.

scholarly journals Glutathione S-transferases of the bovine retina. Evidence that glutathione peroxidase activity is the result of glutathione S-transferase

1982 ◽  
Vol 205 (1) ◽  
pp. 213-217 ◽  
Author(s):  
R P Saneto ◽  
Y C Awasthi ◽  
S K Srivastava
Keyword(s):  
Glutathione Peroxidase ◽  
Peroxidase Activity ◽  
Structural Parameters ◽  
Gel Filtration ◽  
Glutathione Peroxidase Activity ◽  
Glutathione S Transferase ◽  
Ph Optimum ◽  
Bovine Retina ◽  
Apparent Homogeneity ◽  
Glutathione S Transferases

We have purified two isoenzymes of glutathione S-transferase from bovine retina to apparent homogeneity through a combination of gel-filtration chromatography, affinity chromatography and isoelectric focusing. The more anionic (pI = 6.34) and less anionic (pI = 6.87) isoenzymes were comparable with respect to kinetic and structural parameters. The Km for both substrates, reduced glutathione and 1-chloro-2,4-dinitrobenzene, bilirubin inhibition of glutathione conjugation to 1-chloro-2,4-dinitrobenzene, 1-chloro-2,4-dinitrobenzene inactivation of enzyme activity and molecular weight were similar. However, pH optimum and energy of activation were found to differ considerably. Retina was found to have no selenium-dependent glutathione peroxidase activity. The total glutathione peroxidase activity fractionated with the transferases in the gel-filtration range of mol.wt. 49000 and expressed activity with only organic hydroperoxides as substrate. Only the more anionic isoenzyme expressed both transferase and peroxidase activity.

scholarly journals The influence of melatonin on the state of the glutathione system of the rat liver under the conditions of subacute alcoholic intoxication

2014 ◽  
Vol 18 (3 (71)) ◽  
Author(s):  
N. V. Davydova
Keyword(s):  
Glutathione Peroxidase ◽  
Oral Administration ◽  
Rat Liver ◽  
Peroxidase Activity ◽  
Reduced Glutathione ◽  
Alcohol Intoxication ◽  
Transferase Activity ◽  
Glutathione System ◽  
Glutathione Peroxidase Activity ◽  
Glutathione S Transferase

The investigations of certain parameters of glutathione system in the liver of rats under the conditions of subacute alcohol intoxication revealed a decreased content of reduced glutathione and glutathione peroxidase activity as well as an activation of glutathione-S-transferase activity. An oral administration of “Vita-melatonin” against a background of subacute alcohol intoxication in a dose 5 mg/kg during 10 days prevented the changes of the parameters under study.

scholarly journals Glutathione S-transferases of human brain. Evidence for two immunologically distinct types of 26500-Mr subunits

1985 ◽  
Vol 225 (2) ◽  
pp. 375-382 ◽  
Author(s):  
C Theodore ◽  
S V Singh ◽  
T D Hong ◽  
Y C Awasthi
Keyword(s):  
Human Brain ◽  
Gel Electrophoresis ◽  
Human Liver ◽  
Catalytic Properties ◽  
Anionic Form ◽  
Glutathione Peroxidase Activity ◽  
Glutathione S Transferase ◽  
Cationic Form ◽  
Two Dimensional Gel Electrophoresis ◽  
Glutathione S Transferases

Human brain contains one cationic (pI8.3) and two anionic (pI5.5 and 4.6) forms of glutathione S-transferase. The cationic form (pI8.3) and the less-anionic form (pI5.5) do not correspond to any of the glutathione S-transferases previously characterized in human tissues. Both of these forms are dimers of 26500-Mr subunits; however, immunological and catalytic properties indicate that these two enzyme forms are different from each other. The cationic form (pI8.3) cross-reacts with antibodies raised against cationic glutathione S-transferases of human liver, whereas the anionic form (pI5.5) does not. Additionally, only the cationic form expresses glutathione peroxidase activity. The other anionic form (pI4.6) is a dimer of 24500-Mr and 22500-Mr subunits. Two-dimensional gel electrophoresis demonstrates that there are three types of 26500-Mr subunits, two types of 24500-Mr subunits and two types of 22500-Mr subunits present in the glutathione S-transferases of human brain.

scholarly journals Rat lung glutathione S-transferases. Evidence for two distinct types of 22000-Mr subunits

1984 ◽  
Vol 221 (3) ◽  
pp. 609-615 ◽  
Author(s):  
S V Singh ◽  
C A Partridge ◽  
Y C Awasthi
Keyword(s):  
Rat Liver ◽  
The Other ◽  
Rat Lung ◽  
Glutathione S Transferase ◽  
Substrate Specificities ◽  
Liver Glutathione ◽  
Immunological Properties ◽  
Glutathione S Transferases

Two immunologically distinct types of 22000-Mr subunits are present in rat lung glutathione S-transferases. One of these subunits is probably similar to Ya subunits of rat liver glutathione S-transferases, whereas the other subunit Ya′ is immunologically distinct. Glutathione S-transferase II (pI7.2) of rat lung is a heterodimer (YaYa′) of these subunits, and glutathione S-transferase VI (pI4.8) of rat lung is a homodimer of Ya′ subunits. On hybridization in vitro of the subunits of glutathione S-transferase II of rat lung three active dimers having pI values 9.4, 7.2 and 4.8 are obtained. Immunological properties and substrate specificities indicate that the hybridized enzymes having pI7.2 and 4.8 correspond to glutathione S-transferases II and VI of rat lung respectively.

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