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J D Hayes

Publications and source records attributed to J D Hayes.

At least 109 records · Page 6Linked to original sources
PubMed1990

Glutathione S-transferases in alcoholic liver disease.

There is already evidence in alcoholic liver disease, mostly from studies of morphology and cytokeratin distribution, that hepatocytes can undergo a variety of phenotypic changes. This study reports findings of immunohistochemistry using antibodies against members of the glutathione S-transferase supergene family of detoxification enzymes. Hepatocytes in severe alcoholic liver disease coexpressed both alpha and pi class glutathione S-transferase. This coexpression has been previously described only in human fetal liver and in chemically-induced preneoplastic foci in rat liver. The use of function associated markers should provide additional information in the investigation of liver disease.

Adult↗
PubMed1989

Evidence that glutathione S-transferases B1B1 and B2B2 are the products of separate genes and that their expression in human liver is subject to inter-individual variation. Molecular relationships between the B1 and B2 subunits and other Alpha class glutathione S-transferases.

The Alpha class glutathione S-transferases (GSTs) in human liver are composed of polypeptides of Mr 25,900. These enzymes are dimeric, and two immunochemically distinct subunits, B1 and B2, have been described that combine to form GSTs B1B1, B1B2 and B2B2 [Stockman, Beckett & Hayes (1985) Biochem. J. 227, 457-465]. Gradient affinity elution from GSH-Sepharose has been used to resolve the three Alpha class GSTs, and this method has been applied to demonstrate marked inter-individual differences in the hepatic content of GSTs B1B1, B1B2 and B2B2. The B1 and B2 subunits can be resolved by reverse-phase h.p.l.c., and their elution positions suggest that they are equivalent to the alpha chi and alpha y h.p.l.c. peaks described by Ketterer and his colleagues [Ostlund Farrants, Meyer, Coles, Southan, Aitken, Johnson & Ketterer (1987) Biochem. J. 245, 423-428]. The B1 and B2 subunits have now been cleaved with CNBr and the fragments subjected to automated amino acid sequence analysis. The sequence data show that B1 and B2 subunits do not arise from post-translational modification, as had been previously believed for the hepatic Alpha class GSTs, but are instead the products of separate genes; B1 and B2 subunits were found to contain different amino acid residues at positions 88, 110, 111, 112, 116, 124 and 127. The relationship between the B1 and B2 subunits and the cloned GTH1 and GTH2 cDNA sequences [Rhoads, Zarlengo & Tu (1987) Biochem. Biophys. Res. Commun. 145, 474-481] is discussed.

Adult↗
PubMed1989

Glutathione S-transferase in human bile.

Glutathione S-transferase (GST) isoenzymes have been measured by specific radioimmunoassay in human bile samples. GST Mu was found in 50% of samples while GST Pi, GST B1 and GST B2 were present in all samples; GST Pi constituted the major isoenzyme identified. The findings of the radioimmunoassay were confirmed by a one-step purification of GST from bile, using affinity chromatography, followed by their identification using sodium dodecyl sulphate-polyacrylamide gel (SDS-PAGE). Inhibition studies showed that, at the concentrations of bile salts found in bile, GST Pi would have little or no enzymic activity. It is proposed that GST Pi acts as a carrier protein of toxic, non-substrate, ligands to remove as yet unidentified substances from biliary epithelial cells and prevent their reabsorption.

Bile↗
PubMed1989

Differential induction of class alpha glutathione S-transferases in mouse liver by the anticarcinogenic antioxidant butylated hydroxyanisole. Purification and characterization of glutathione S-transferase Ya1Ya1.

A novel cytosolic Alpha class glutathione S-transferase (GST) that is not normally expressed in mouse liver was found to be markedly induced (at least 20-fold) by the anti-carcinogenic compound butylated hydroxyanisole. This enzyme (designated GST Ya1 Ya1) did not bind to either the S-hexylglutathione-Sepharose or the glutathione-Sepharose affinity matrices, and purification was achieved by using bromosulphophthalein-glutathione-Sepharose. The purified isoenzyme, which comprises subunits of Mr 25,600, was characterized, and its catalytic, electrophoretic, immunochemical and structural properties are documented. GST Ya1 Ya1 was shown to be distinct from the Alpha class GST that is expressed in normal mouse liver and is composed of 25,800-Mr subunits; the Alpha class isoenzyme that is constitutively expressed in the liver is now designated GST Ya3 Ya3. Hepatic concentrations of GST Ya3 Ya3 were not significantly affected when mice were treated with butylated hydroxyanisole. Both Pi class GST (subunit Mr 24,800) and Mu class GST (subunit Mr 26,400) from female mouse liver were induced by dietary butylated hydroxyanisole. By contrast, hepatic concentrations of microsomal GST (subunit Mr 17,300) were unaffected.

Animals↗
PubMed1989

Human microsomal glutathione S-transferase. Its involvement in the conjugation of hexachlorobuta-1,3-diene with glutathione.

A microsomal glutathione S-transferase (GST) was purified from human liver. This enzyme was shown to have characteristics similar to those of the rat microsomal GST described by Morgenstern & De Pierre [(1983) Eur. J. Biochem. 134, 591-597]. The specific activity of human microsomal GST towards 1-chloro-2,4-dinitrobenzene or cumene hydroperoxide can be stimulated by treating the enzyme with N-ethylmaleimide. This enhancement of activity is accompanied by increased sensitivity to inhibition by haematin and cholic acid. The subunit Mr values of the rat and human enzymes are similar (approx. 17,300), and the proteins are immunologically related. During purification, both human and rat microsomal GST enzymes are the only hepatic proteins obtained from Triton X-100-solubilized microsomal fractions that show activity towards the nephrotoxin hexachlorobuta-1,3-diene. The involvement of microsomal GST in toxification reactions is discussed.

Animals↗
PubMed1989

Expression of glyoxalase, glutathione peroxidase and glutathione S-transferase isoenzymes in different bovine tissues.

(1) The tissue-specific expression of various glutathione-dependent enzymes, including glutathione S-transferase (GST), glutathione peroxidase and glyoxalase I, has been studied in bovine adrenals, brain, heart, kidney, liver, lung and spleen. Of the organs studied, liver was found to possess the greatest GST and glyoxalase I activity, and spleen the greatest glutathione peroxidase activity. The adrenals contained large amounts of these glutathione-dependent enzymes, but significant differences were observed between the cortex and medulla. (2) GST and glyoxalase I activity were isolated by S-hexylglutathione affinity chromatography. Glyoxalase I was found in all the organs examined, but GST exhibited marked tissue-specific expression. (3) The alpha, mu and pi classes of GST (i.e., those that comprise respectively Ya/Yc, Yb/Yn and Yf subunits) were all identified in bovine tissues. However, the Ya and Yc subunits of the alpha class GST were not co-ordinately regulated nor were the Yb and Yn subunits of the mu class GST. (4) Bovine Ya subunits (25.5-25.7 kDa) were detected in the adrenal, liver and kidney, but not in brain, heart, lung or spleen. The Yc subunit (26.4 kDa) was expressed in all those organs which expressed the Ya subunit, but was also found in lung. The mu class Yb (27.0 kDa) and Yn (26.1 kDa) subunits were present in all organs; however, brain, lung and spleen contained significantly more Yn than Yb type subunits. The pi class Yf subunit (24.8 kDa) was detected in large amounts in the adrenals, brain, heart, lung and spleen, but not in kidney or liver. (5) Gradient affinity elution of S-hexylglutathione-Sepharose showed that the bovine proteins that bind to this matrix elute in the order Ya/Yc, Yf, Yb/Yn and glyoxalase I. (6) In conclusion, the present investigation has shown that bovine GST are much more complex than previously supposed; Asaoka (J. Biochem. 95 (1984) 685-696) reported the purification of mu class GST but neither alpha nor pi class GST were isolated.

Adrenal Glands↗
PubMed1989

Glutathione S-transferase isoenzymes in human tumours and tumour derived cell lines.

An increasing body of evidence indicates that glutathione S-transferases play a role in the intrinsic and acquired resistance of tumours to anticancer drugs. In view of the wide use of tumour cell lines to understand the factors which confer either sensitivity or resistance to chemotherapeutic agents we have determined glutathione S-transferase (GST) activity and isozyme composition in nine human cell lines. These data have been compared with the values obtained in solid tumours. In most cases overall GST activity was higher in the tumours than in the cell lines. This was most pronounced for the breast tumour samples relative to MCF7 cell line. The pi class GST subunit was present at similar concentration in the cell lines and the tumours, and in most cases was the most abundant subunit present. The alpha and mu class GST were expressed in most of the cell lines but at much lower concentration than the pi class subunit. Also considerable variability particularly in the expression of the mu subunits was observed. This was also the case for the expression of these subunits in the solid tumour samples. The levels of these GSTs (when expressed) in the solid tumours was invariably higher than that observed in the cell lines. There are therefore several similarities but also some significant differences in GST expression in solid tumours and cell lines. Whether the differences are because expression is lost during the generation of the cell lines or whether it reflects the individuality of human tumours remains to be clearly established.

Cell Line↗
PubMed1989

Effect of nicardipine infusion on the release of glutathione S-transferase following halothane anaesthesia.

To assess the possible protective effect of calcium channel blockade on hepatic function after halothane anaesthesia, 80 patients were allocated randomly to receive an i.v. infusion of either nicardipine or normal saline. Plasma concentration of glutathione S-transferase B1 subunits (GST) was measured as a sensitive index of hepatic damage. Data from 53 patients were analysed. Plasma GST concentration increased significantly at 3 and 6 h after induction of anaesthesia in the placebo group (P less than 0.01), and at 3 h (P less than 0.01) and 6 h (P less than 0.05) in the nicardipine group. The administration of nicardipine resulted in a greater increase in plasma GST concentrations at 3 h than did placebo (P less than 0.05), mainly because of a greater increase in males than in females. The increase in GST at 3 h was related inversely to plasma concentration of nicardipine both at the end of the exponential infusion (P less than 0.01) and at 2 h after induction (P less than 0.05), when males had lower plasma nicardipine concentrations than females (P less than 0.05). Calcium channel blockade with nicardipine in the dose administered was not shown to reduce liver dysfunction after halothane anaesthesia.

Adolescent↗
PubMed1989

Glutathione S-transferase isoenzymes in human renal carcinoma demonstrated by immunohistochemistry.

Glutathione S-transferase (GST) in man comprise at least four gene families. Three of these families give rise to cytosolic isoenzymes (alpha, mu and pi classes), whilst the remainder is membrane bound and has been called microsomal GST. These enzymes are implicated in tumourogenesis and both pi class GST and alpha class GST have been described in four cases of human renal cell carcinoma. Using specific polyclonal rabbit antisera we have demonstrated by immunohistochemistry that all 12 renal carcinomas studied contained GST pi. Most tumours also contained GST alpha, GST mu and microsomal GST isoenzymes but their distribution was heterogeneous and sometimes very focal. This heterogeneity of GST isoenzyme distribution within tumours has not been well documented previously, but is relevant to our understanding of the functions of GST, and to the interpretation of biochemical quantification experiments using tissue extracts.

Carcinoma, Renal Cell↗
PubMed1989

Cytosolic and microsomal glutathione S-transferase isoenzymes in normal human liver and intestinal epithelium.

Glutathione S-transferases are a group of drug metabolising and detoxification enzymes. We have studied the distribution of four isoenzymes, acidic, basic, neutral, and microsomal GST in human liver, gall bladder, and small and large intestinal epithelium by immunohistochemistry. Antibodies were raised in rabbits to purified GST subunits and several formalin fixed paraffin sections of each human tissue studied using the peroxidase-antiperoxidase method. Staining density was graded from very strong (+++) to negative (-). All four enzymes were identified within the liver, the acidic GST being found almost exclusively within the biliary epithelium. The gall bladder epithelium stained strongly for acidic and basic GST. In the small intestinal epithelium the acidic and neutral GST were readily identified in villi and crypts, whilst basic GST was found only in the villi and microsomal only in the crypts. In the colonic mucosa only acidic GST could consistently be identified. This histological heterogeneity may have functional implications for these enzymes in human hepatobiliary and intestinal tissue.

Cytosol↗
PubMed1989

Distribution of glutathione S-transferase isoenzymes in human kidney: basis for possible markers of renal injury.

To determine whether the tissue distribution of glutathione S-transferase (GST) isoenzymes could define the precise nature of renal injury, 13 adult kidneys were studied, using specific antibodies raised against purified isoenzymes. Basic GST stained strongly proximal convoluted tubules and some medullary tubules; acidic GST stained strongly distal convoluted tubules and medullary tubules; neutral GST stained similarly to acidic GST, but weaker, and microsomal GST stained glomerular and interstitial endothelium and collecting ducts deep in the medulla, although there was considerable variation in staining intensity among cases. It is suggested that the measurement of these isoenzymes in serum and urine may help to elucidate the localisation of tissue damage, which may be particularly valuable in patients with cyclosporine toxicity following renal transplantation.

Glutathione Transferase↗
PubMed1989

Measurements of glutathione S-transferase B1 in plasma after birth asphyxia: an early indication of hepatocellular damage.

Concentrations of glutathione S-transferase (glutathione transferase; EC 2.5.1.18) B1 and B2 subunits (B1 and B2) and activity of alanine aminotransferase (ALT; EC 2.6.1.2) were measured in sequential plasma samples taken from 14 infants with birth asphyxia. Within 6 h of asphyxia, abnormal concentrations of B1 were found in 11 infants, whereas only seven infants showed abnormal ALT activities at this time. In plasma sampled 24 h after birth, values for ALT were abnormal in 10, whereas values for B1 were abnormal in six. Abnormal concentrations of B2 were found in relatively few of these infants, apparently because this monomer is poorly expressed in liver samples obtained up to 41 weeks after conception. We conclude that measurement of B1 may provide a useful index of hepatic impairment in birth-asphyxiated infants.

Asphyxia Neonatorum↗
PubMed1988

Selective elution of rodent glutathione S-transferases and glyoxalase I from the S-hexyglutathione-Sepharose affinity matrix.

1. The major hepatic glutathione S-transferases (GSTs) from gerbil, guinea-pig, hamster, mouse and rat comprise Ya- (Mr 25,500-25,800), Yb- (Mr 26,100-26,400), Yc- (Mr 27,000-27,500) and Yf- (Mr 24,800) type subunits. 2. In all rodent species the GST subunits possess characteristic affinities for S-hexyglutathione-Sepharose and are eluted at distinct positions when a gradient of counter-ligand is employed to develop this affinity gel. The enzymes that bind to this matrix can be eluted, according to their subunit composition, in the order Ya-, Yc-, Yf- and Yb-containing GST; glyoxalase I, also retained by S-hexylglutathione-Sepharose, is eluted after the major GST YbYb peak. 3. Conditions are also described for the isocratic affinity elution of S-hexylglutathione-Sepharose that allow rat GST to be divided into four separate fractions (pools 1-4). A further fraction (pool 5) can be prepared from material that does not bind S-hexylglutathione-Sepharose and is obtained by chromatography on glutathione-Sepharose. 4. The sequential use of S-hexylglutathione-Sepharose and glutathione-Sepharose has facilitated the isolation of novel GSTs by enriching the various affinity-purified fractions with different subunits. This strategy allowed the Yk (Mr 25,000) and Yo (Mr 26,500) subunits from rat testis as well as Y1 (Mr 25,700) from rat kidney to be rapidly purified. 5. The binding properties of GST subunits for S-hexylglutathione-Sepharose have been compared with their Km values for GSH. The elution order from this matrix is inversely related to the Km value. The GSTs that do not bind to S-hexylglutathione-Sepharose have considerably higher Km values for GSH (i.e. greater than 2.0 mM) than do those enzymes that readily bind to the affinity gel (i.e. 0.13-0.77 mM). GST YkYk and YoYo, which have weak affinities for S-hexylglutathione-Sepharose, possess intermediate Km values for GSH of 1.0 and 1.2 mM respectively.

Animals↗
PubMed1988

Purification of acidic glutathione S-transferases from human lung, placenta and erythrocyte and the development of a specific radioimmunoassay for their measurement.

Human acidic glutathione S-transferases (GST) have been purified from placenta, lung and erythrocytes. The purification protocol resulted in a high yield of pure protein for each tissue, when compared to previous procedures. An apparent subunit Mr of 24,800 was calculated for each of the acidic GST and each enzymes had a pI of 4.75. No immunochemical differences were detected between the acidic GST isolated from the three tissues. A specific and sensitive radioimmunoassay suitable for the measurement of human acidic GST in plasma or tissues is described.

Erythrocytes↗