Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A prospective study was performed in the Dutch flower bulb culture to investigate the possible effects of subchronic exposure to the soil fumigant 1,3-dichloropropene (DCP) on liver and kidney function and on glutathione conjugation capacity in blood. Urine spot samples and venous blood samples from 14 workers applying DCP (applicators) were taken at the start of the season in July, and after the season in October. The parameters of liver function measured were: alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, gamma-glutamyltranspeptidase, and total bilirubin (conjugated and unconjugated). Total bilirubin was significantly decreased from 9.5 before to 7.0 mumol/l after the season. In combination with an increase in serum gamma-glutamyltranspeptidase activity from 12.5 to 19.5 U/l this indicates moderate hepatic enzyme induction. To study renal function, creatinine and beta 2-microglobulin in serum, and beta 2-microglobulin, albumin, alanine aminopeptidase, beta-galactosidase, and retinol binding protein in urine were measured. The glomerular function parameters albumin in urine and creatinine in serum changed significantly during the season: albumin concentration increased from 5.2 to 7.6 mg/l, whereas creatinine concentration [corrected] decreased from 93.0 to 87.5 mumol/l. The tubular function parameter retinol binding protein also increased in concentration from 20.0 to 26.9 micrograms/l. Therefore, a subclinical nephrotoxic effect of subchronic exposure to DCP cannot be excluded. Effects on glutathione conjugation capacity were studied by measuring erythrocyte glutathione S-transferase activity and blood glutathione concentrations. The activity of glutathione S-transferase in erythrocytes was significantly decreased from 4.7 before to 3.3 U/g haemoglobin after the season. The same was true for the blood glutathione concentrations, which decreased from 0.93 to 0.82 mM.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Biological effect monitoring of occupational exposure to 1,3-dichloropropene: effects on liver and renal function and on glutathione conjugation. 191 9

Rabbit alveolar macrophages which were treated at 0 degrees C with phenylarsine oxide and then incubated at 37 degrees C for 10 min exhibited a two- to threefold increase in surface receptor activity for macroglobulin.protease complexes, diferric transferrin, and mannose-terminal glycoproteins. Analysis of the concentration-dependence of ligand binding indicated that changes in ligand-binding activity were due to changes in receptor number rather than alterations in ligand-receptor affinity. Surface receptor number could also be increased by treatment of cells with three other sulfhydryl reagents, N-ethylmaleimide, p-chloromercurobenzoate, and iodoacetic acid. The increase in receptor activity was maximal after 10 min and decreased over the next hour. This decrease in cell-associated receptor activity was due to the release of large membrane vesicles which demonstrated a uniform buoyant density by isopycnic sucrose gradient centrifugation. Treatment of cells with phenylarsine oxide did not decrease the cellular content of lactate dehydrogenase or beta-galactosidase, indicating that cell integrity was maintained and lysosomal enzyme release did not occur. Our studies indicate that phenylarsine oxide treatment in the presence of extracellular Ca2+ results in the fusion of receptor-containing vesicles with the cell surface.
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PMID:Phenylarsine oxide-induced increase in alveolar macrophage surface receptors: evidence for fusion of internal receptor pools with the cell surface. 240 94

Volume, specific gravity, creatinine, lactate dehydrogenase (LDH), leucine aminopeptidase (LAP), beta-galactosidase (GAL), leucocytes, erythrocytes, nitrite, protein (albumin), glucose, ketone, urobilinogen, bilirubin and pH were estimated in urine of rats after single (by gavage) or repeated (via drinking water) oral administration of diethylene glycol (DEG). Following single or repetitive doses (daily over 90 days) of 0.2 g DEG kg-1 body weight, no change in renal function was observed (no effect level). In urine of rats treated once with 0.7 g DEG kg-1 body weight, LDH activity was significantly enhanced one day after treatment. A single dose of 2.0 g DEG kg-1 body weight resulted in an additional rise in urinary GAL activity two days after treatment, a significant rise of urinary volume and a decrease in creatinine concentration and pH on the first day. One day following a single dose of 8.0 g DEG kg-1 body weight, in addition to the changes mentioned before, LAP activity was significantly elevated and the specific gravity decreased. However, in all experiments the wet weight of the kidneys remained normal as compared to controls. The results thus show dose-dependent changes in several renal parameters, indicating a slight-to-moderate and reversible renal impairment.
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PMID:Transient renal impairment in rats after oral exposure to diethylene glycol. 259 30

Adler and Martin (1983, Curr. Eye Res. 2, 359-66) found cathepsin D to be present in crude preparations of bovine interphotoreceptor matrix (IPM). The purpose of the present study was to determine, by investigating several acid hydrolases in purer IPM samples, whether hydrolytic enzymes abundant in RPE lysosomes were present also as normal components of the IPM. IPM was prepared from bovine eyes by the introduction of a small bleb of buffer between the neural retina and the RPE. These IPM samples were free from significant contamination by surrounding tissues; they contained IRBP as their only major protein, and had negligible amounts of lactate dehydrogenase and ROS-specific proteins. Most acid hydrolases were assayed fluorometrically by measuring the 4-methylumbelliferone released upon hydrolysis of appropriate derivatives; the substrate for cathepsin was hemoglobin. The amounts of the enzymes found in the IPM were far from uniform and could not be correlated with enzyme activities in either RPE or retina homogenates. The hydrolases in the IPM varied in amount from beta-galactosidase (28% of the RPE level), through N-acetyl-beta-glucosaminidase (20%), alpha-fucosidase (15%), beta-glucuronidase (12%), alpha-glucosidase (8%), cathepsin D (7%), alpha-mannosidase (7%), down to beta-glucosidase, acid phosphatase, and acid lipase (trace amounts, less than 1%). These results agree with the relative amounts of enzymes found by Wilcox (1987) to be secreted into the medium by cultured human RPE cells. Furthermore, the rank order of hydrolases in the IPM is the same as that for hydrolases secreted (but not recaptured) by human fibroblasts in I-cell disease. The conclusion from these correlations is that lysosomal enzymes are probably secreted, as a normal process, by the RPE into the IPM, where they may have a role in digesting shed outer segments and in catabolizing IPM components.
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PMID:Selective presence of acid hydrolases in the interphotoreceptor matrix. 261 85

Endothelial injury has been proposed as a feature of a wide variety of vascular diseases, and release of endothelial lysosomal hydrolases could contribute to the pathological changes seen. We have determined the relative activities of 14 glycosidases, two esterases and four peptide hydrolases in human umbilical vein endothelial cells and investigated whether known agonists of endothelial function, or materials known to modulate hydrolase secretion in other phagocytic cells, influenced the activity or secretion of these enzymes by human umbilical vein endothelial cells. Hexosaminidase, beta-galactosidase, beta-glucuronidase and alpha-iduronidase accounted for most of the measured glycosidase activity. Acid phosphatase activity greatly exceeded arylsulphatase activity, and most of the measured peptidase activity was due to acid peptidases. Optimum pH and apparent Km values were determined for the most abundant hydrolases. Exposure of human umbilical vein endothelial cells to bradykinin, thrombin or interleukin-1 resulted in negligible release of either hexosaminidase or lactate dehydrogenase (LDH), in contrast to phorbol myristate acetate, which caused a parallel, dose-dependent release of both enzymes. Treatment of these cells with calcium ionophore A23187, trypsin or platelet-activating factor, caused less than 10% release of either hexosaminidase or LDH. Agents known to modulate lysosomal enzyme secretion by other phagocytic cells failed to induce selective secretion of lysosomal enzymes by human umbilical vein endothelial cells.
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PMID:Lysosomal hydrolases of human vascular cells: response to agonists of endothelial function. 264 39

In order to have an insight into the role of host lysosomal enzymes in the intracellular survival of Leishmania parasites, the activities of beta-galactosidase, alpha-mannosidase, and N-acetyl-beta-D-glucosaminidase were studied in peritoneal macrophages of hamsters infected with L. donovani. There was a significant decrease of all three lysosomal enzymes after infection. Heat-killed or formalin-treated parasites failed to inhibit the enzymes, instead a slight stimulation was observed. Purified excreted factor from promastigotes had no effect on the enzymes except beta-galactosidase which was inhibited up to 20%. Inhibition of enzymes was not due to increased secretion after infection. The absence of induction of any endogenous macrophage inhibitor was confirmed by mixed experiments. The levels of 5'-nucleotidase and lactate dehydrogenase remained unchanged after infection. Thus, the inhibition of lysosomal enzymes appears to be the effect of infection process and reflects to actua decrease rather than increased secretion or the action of any inhibitors present in Leishmania promastigotes.
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PMID:Suppression of macrophage lysosomal enzymes after Leishmania donovani infection. 271 50

The possible occurrence of circadian and circannual rhythms in the plasma concentrations of the following enzymes of lysosomal origin was assessed: beta-D-N-acetylglucosaminidase (EC 3.2.1.30) beta-D-glucuronidase (EC 3.2.1.31), beta-D-glucosidase (EC 3.2.1.21), beta-D-galactosidase (EC 3.2.1.22), alpha-D-galactosidase (EC 3.2.1.23), alpha-L-fucosidase (EC 3.2.1) and alpha-D-mannosidase (EC 3.2.1.24). The circadian rhythm was studied in 16 women (aged: 17-24 years) and 13 men (age: 23 years) volunteers; the circannual rhythm, in 10 women and 8 men (age: 20-25 years). The circadian rhythm was detected in all the tested enzymes of women, and only in alpha-D-galactosidase, beta-D-glucosidase, alpha-D-mannosidase and beta-D-acetylglucosaminidase of men. A statistically significant difference between genders in the circadian rhythm was exhibited by beta-D-galactosidase (MESOR; amplitude) beta-D-glucosidase (MESOR; amplitude; acrophase) beta-D-N-acetylglucosaminidase, beta-D-glucuronidase and alpha-D-galactosidase (MESOR) and alpha-L-fucosidase (amplitude, acrophase). A circannual rhythm was detected in all the tested enzymes with the exception of beta-D-glucuronidase and beta-D-N-acetylglucosaminidase; no statistically significant difference between genders was detected. The group rhythms of some of the enzymes (alpha-D-galactosidase, beta-D-glucosidase, beta-D-galactosidase) showed similar values of both circadian and circannual acrophases, suggesting that they may subjected as a group to the same chronobiological coordination, possibly mediated by hormones. The chronobiological rhythms of lysosomal enzymes were different from those of lactate dehydrogenase and alpha 1-antitrypsin, indicating that these rhythms are not merely reflecting fluctuations of the water content of plasma. No in-phase relationship was observed between the circadian and circannual rhythms of plasma cortisol and those of the tested lysosomal enzymes, excluding a direct chronobiological and possibly functional relationship between this hormone and lysosomal enzymes.
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PMID:Chronobiological study of several enzymes of lysosomal origin in human plasma. 278 34

Radiation inactivation is a method to determine the apparent target size of molecules. In this report we examined whether radiation inactivation of various enzymes and brain receptors is influenced by the preparation of samples preceding irradiation. The apparent target sizes of endogenous acetylcholinesterase and pyruvate kinase from rat brain and from rabbit muscle and benzodiazepine receptor from rat brain were investigated in some detail. In addition the target sizes of alcohol dehydrogenase (from yeast and horse liver), beta-galactosidase (from Escherichia coli), lactate dehydrogenase (endogenous from rat brain), and 5-HT2 receptors, acetylcholine muscarine receptors, and [35S] butyl bicyclophosphorothionate tertiary binding sites from rat brain were determined. The results show that apparent target sizes are highly influenced by the procedure applied for sample preparation before irradiation. The data indicate that irradiation of frozen whole tissue as opposed to lyophilized tissue or frozen tissue homogenates will estimate the smallest and most relevant functional target size of a receptor or an enzyme.
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PMID:The apparent target size of rat brain benzodiazepine receptor, acetylcholinesterase, and pyruvate kinase is highly influenced by experimental conditions. 284 37

Pulmonary alveolar macrophages exposed to very short chrysotile asbestos fibers present a typical cytotoxic response: extracellular releases of lactate dehydrogenase and beta-galactosidase, and a decrease in cellular ATP content. The objective of this study was to determine if nicotinamide and 3-aminobenzamide, two inhibitors of the ADP-ribosyl transferase, could modify the in vitro toxicity of chrysotile fibers. After 30 min of pre-exposure with each of the two inhibitors, pulmonary alveolar macrophage monolayers were concomitantly exposed for 18 hours to 50 micrograms of fibers. It was observed that, in a dose-effect relationship (5 to 30 mM), nicotinamide was very effective in reducing the extracellular liberation of the marker enzymes. At 30 mM, the enzyme releases in the medium had returned to control values; the restoration of cell viability was confirmed by ATP levels. Up to 5 mM 3-aminobenzamide did not provide any protection against chrysotile cytotoxicity. Nicotinic acid, a structural analogue of nicotinamide, but not an inhibitor of the ADP-ribosyl transferase, also showed no protective effect. Nicotinamide and 3-aminobenzamide increased the intracellular NAD+ pools, respectively by 350% and 250%. However, with or without additives, the chrysotile fibers caused a constant and significant decrease in NAD+ levels (40-55 pmoles). These results suggest that the inhibition of the nuclear ADP-ribosyl transferase is not the major mechanism by which nicotinamide protects pulmonary alveolar macrophages against the toxicity of chrysotile asbestos fibers.
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PMID:The cytotoxicity of chrysotile asbestos fibers to pulmonary alveolar macrophages. I. Effects of inhibitors of ADP-ribosyl transferase. 285 30

Urinary excretion of lactate dehydrogenase (LDH), glutathione-S-transferase (GST), leucine arylamidase (LAS), gamma-glutamyltransferase (GGT), beta-galactosidase (GAL), beta-N-acetyl-D-glucosaminidase (NAG), sodium, and glucose were determined in female Sprague-Dawley rats the subsequent three days after intraperitoneal treatment with single doses of 4.5 mg CdCl2 X 1H2O/kg, 20 mg Na2CrO4/kg, and 0.75 mg HgCl2/kg body weight. Although the pathological effects were localized within the same part of the nephron (i.e., the proximal tubule), there were marked differences with regard to the extent and time course of the parameters affected. Treatment with cadmium resulted essentially in a marked decline in sodium and glucose excretion. The administration of chromate led to a slightly to moderately elevated excretion of the enzyme activities measured with the cytosolic LDH as the most increased enzyme (ca. 500% of controls on Day 3 postadministration). Median glucose excretion was unaffected whereas sodium excretion was transiently reduced. The maximum of enzyme excretion after HgCl2 was essentially the same on the first day postadministration and the amount of enzyme activity in urine up to 20 times higher compared to that after chromium. Sodium excretion was below that of controls on Days 2 and 3, whereas glucose excretion was markedly elevated (up to 8000% of controls). The results indicate that it is possible to discriminate with the use of selected urinary enzymes, substrates, and electrolytes various kinds of nephrotoxic actions not only in different but also within the same part of the nephron.
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PMID:Comparative investigations on the effects of acute intraperitoneal cadmium, chromium, and mercury exposure on the kidney. 287 41


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