Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.31 (beta-glucuronidase)
7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Effect of different concentration of non-ionic detergents (Triton X-100, Triton X-305, BRIJ-35 and Triton WR-1339) on total and non-sedimentable activity of 8 rat liver lysosome enzymes (acid phosphatase, acid DNase, acid RNase, arylsulphatases A and B, beta-glucuronidase, beta-galactosidase, beta-glucosidase and beta-acetylglucosaminidase) was studied. Only Triton X-100 at the concentration of 0.1% (and higher) was found to release completely lysosome enzymes. Low concentrations of Triton X-100 (0.025-0.05%) were used to characterize the strength of enzyme binding: the level of releasing acid DNase, beta-galactosidase, beta-glucuronidase and acid phsophatase being considerably higher than that of other lysosome enzymes studied. On the basis of the data obtained a method is worked out, which is suitable for series studies of the stability of lysosome membranes under different physiological and pathological conditions. The essence of the method is the treatment of membrane particles with increasing concentrations of Triton X-100 (0.025; 0.05 AND 0.1%) AND THE SUCCESSIVE ESTIMATION OF NON-Sedimentable activity of marker enzymes. The method detected troubles in the stability of rat liver lysosome membranes under starvation, protein deficiency and aging.
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PMID:[Determination of lysosome membrane stability]. 120 72

Recent studies indicate that altered lysosomal function may be involved in the early stages of pancreatic injury. Chronic consumption of ethanol increases rat pancreatic lysosomal fragility. The aim of this study is to determine whether the lysosomal fragility observed after chronic ethanol consumption is mediated by ethanol per se, its oxidative metabolite acetaldehyde or cholesteryl esters (substances which accumulate in the pancreas after ethanol consumption). Pancreatic lysosomes from chow fed rats were incubated for 30 minutes at 37 degrees C with ethanol, acetaldehyde or phosphatidylcholine vesicles containing cholesteryl oleate. Lysosomal stability was then assessed by determination of: (a) Latency--that is, the per cent increase in lysosomal enzyme activity after addition of Triton X-100 and (b) Supernatant activity--that is, the proportion of lysosomal enzyme remaining in the supernatant after resedimentation of lysosomes. Acid phosphatase, N-acetyl glucosaminidase, beta-glucuronidase and cathepsin B were assayed as lysosomal marker enzymes. Lysosomes incubated with homogenising medium alone or equivalent volumes of phosphatidylcholine vesicles without cholesteryl oleate were used as controls. Cholesteryl oleate at concentrations of 15 and 20 mM increased pancreatic lysosomal fragility as shown by decreased latency and increased supernatant enzyme. In contrast, ethanol (150 mM) and acetaldehyde (5 mM) had no effect on lysosomal stability in vitro. These results suggest that increased pancreatic lysosomal fragility observed with ethanol may be mediated by cholesteryl ester accumulation rather than by ethanol or acetaldehyde.
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PMID:Effects of ethanol, acetaldehyde and cholesteryl esters on pancreatic lysosomes. 139 35

The changes of hepatic lysosomal enzymes and the hepatic cellular damage were investigated in rats with obstructive jaundice, phospholipase A2 (PL-A2) which is a strong labilizer of lysosomal membrane was added in the lysosomal fraction of rat's liver with various concentration. The activities of cathepsin D and beta-glucuronidase those were released by PL-A2 from lysosomal fraction were measured. The values of both lysosomal enzyme activities showed positive relation to the concentration of PL-A2, and were remarkably increased in obstructive jaundiced rats than in normal rats. We also measured the activity of cathepsin D released by Triton X-100 from lysosomal fraction of normal and jaundiced rat liver. The amount of lysosomal enzyme was more increased in obstructive jaundiced liver than in normal liver. Fragility score as the indicator for lysosomal membranous fragility was calculated as the ratio of cathepsin D released by PL-A2 to that released by Triton X-100. Fragility score was more increased in obstructive jaundiced rats than in normal rats. In conclusion, these data suggest that the fragility of lysosomal membrane could be enhanced in obstructive jaundiced liver.
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PMID:[Changes in lysosomal enzymes and cell damage of the liver in obstructive jaundiced rats]. 155 86

Evidence is accumulating that cigarette smoking plays an important role in the protease-antiprotease imbalance in alpha 1-antitrypsin-sufficient emphysema. Since most smokers, however, do not develop emphysema, it has to be presumed that other factors in addition to smoking contribute to the origin of the imbalance. The major source of proteases is the polymorphonuclear leucocyte (PMN). We tested the hypothesis that an abnormality in the releasability of PMN might predispose for the development of emphysema. Therefore, the release of elastase, myeloperoxidase, and beta-glucuronidase from PMN was investigated in patients with emphysema and healthy controls, matched for sex, age, and smoking habits. PMN were isolated from peripheral blood and stimulated with calcium-ionophore A23187, formyl-methionyl-leucyl-phenylalanine (FMLP), and serum-treated zymosan (STZ). Total enzyme content of PMN was measured after cell lysis with Triton X-100. Total elastase, myeloperoxidase, and beta-glucuronidase content of PMN were not significantly different in healthy subjects and patients with emphysema. In vitro release of elastase and myeloperoxidase from both stimulated and unstimulated PMN was not significantly different in healthy subjects and emphysematous patients. Moreover, no differences were found between smoking and ex-smoking individuals. Beta-glucuronidase release tended to be lower in patients with emphysema than in healthy controls. We conclude that an abnormality in the releasability of peripheral PMN is unlikely to be a pathogenetic factor in emphysema.
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PMID:In vitro release of neutrophil elastase, myeloperoxidase and beta-glucuronidase in patients with emphysema and healthy subjects. 166 65

Long-chain fatty acids inhibit glucuronidation of benzo(a)pyrene phenols in perfused liver; therefore, this study was designed to investigate interactions of fatty acids with beta-glucuronidase, glucuronosyl transferase, and energy supply. In beta-glucuronidase-deficient C3H/He mice, infusion of oleate (250 microM) increased the release of free benzo(a)pyrene phenols from 14 to 33 nmol/g/h and decreased release of glucuronides into the perfusate from 25 to 17 nmol/g/h. Rates of accumulation of glucuronides in the liver were also diminished from 11 to 4 nmol/g/h after infusion of oleate (250 microM). Fatty acids did not affect the release of benzo(a)pyrene metabolites into bile, and the ratio of free phenol to glucuronide production was increased from 0.57 to 1.30. A similar trend was observed in livers from DBA/2 mice that have beta-glucuronidase. Rates of hydrolysis of benzo(a)pyrene-O-glucuronide were not altered in isolated microsomes by addition of oleoyl coenzyme A (CoA) or octanoyl CoA (10- approximately 100 microM). Thus, we conclude that fatty acids do not alter glucuronidation by acting on beta-glucuronidase. The concentration of cofactors (UDP-glucuronic acid, UDP-glucose, and adenine nucleotides) involved in hepatic conjugation was not altered by infusion of concentrations of oleate (300 microM) that inhibited glucuronidation in perfused livers. When oleate concentrations were increased to 600 microM, UDP-glucuronic acid and UDP-glucose decreased 44 and 49%, respectively, and the ATP:ADP ratio declined concomitantly. Oleoyl CoA inhibited UDP-glucuronosyl transferase noncompetitively (half-maximal inhibition, 10 microM) in microsomes with 3-hydroxy-benzo(a)pyrene or p-nitrophenol as substrate. In contrast, octanoyl CoA was a very poor inhibitor of transferase activity. Inhibition of the transferase by oleoyl CoA was increased markedly by treatment with detergents (Triton X-100), i.e., half-inhibition of glucuronosyl transferase was obtained with about 2 microM oleoyl CoA. Inhibition of UDP-glucuronosyl transferase by oleoyl CoA was also increased in a dose-dependent manner by albumin, possibly due to increasing access of the CoA derivative to the enzyme. Collectively, these data indicate that fatty acids diminish glucuronidation via the formation of acyl CoA compounds that inhibit UDP-glucuronosyl transferase noncompetitively.
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PMID:Inhibition of glucuronidation of benzo(a)pyrene phenols by long-chain fatty acids. 190 48

Gram-negative rods were presumptively identified directly from blood cultures within 15 min as Escherichia coli, a member of the Klebsiella-Enterobacter group, or oxidase positive. Samples of artificially seeded blood cultures (193 cultures) and patient blood cultures (78 cultures) were filtered into a Dynadepth test card with the Bac-T-Screen instrument (Vitek, Inc., Hazelwood, Mo.). Triton X-100 was then filtered into the test card to lyse the blood cells but not the entrapped bacteria, and either methylumbelliferone-labeled substrates or oxidase reagent was applied to the filter surface. The oxidase test was read within 30 s, and the methylumbelliferone and indole tests were read after a 10-min incubation at room temperature. Positive beta-galactosidase, beta-glucuronidase, and indole test results predicted the identification of E. coli with a 96 to 100% sensitivity and a 99 to 100% specificity. Positive beta-xylosidase and beta-galactosidase test results and negative oxidase and beta-glucuronidase test results were 85 to 93% sensitive and 100% specific for a Klebsiella-Enterobacter organism. A positive oxidase test result and negative beta-glucuronidase, beta-xylosidase, and indole test results were highly predictive of Pseudomonas aeruginosa (sensitivity, 100%; specificity, 99%). The procedures described are rapid and simple and provide a direct presumptive identification of the gram-negative rods most commonly found in blood cultures.
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PMID:Rapid presumptive identification of gram-negative rods directly from blood cultures by simple enzymatic tests. 210 96

The effect of various metals on uridine diphosphate (UDP)-glucuronyltransferase and beta-glucuronidase activities in rat liver microsomes was investigated. The presence of Mn2+, Cd2+, Zn2+, V5+, Ni2+, Co2+, Cu+ or Ca2+ (20 microM) in the enzyme reaction mixture did not cause a significant alteration of UDP-glucuronyltransferase activity in hepatic microsomes. Of these metals, Zn2+ and Cd2+ (20 microM) caused a remarkable increase in hepatic microsomal beta-glucuronidase activity. Appreciable effects of Zn2+ and Cd2+ on beta-glucuronidase activity were seen at 5.0 microM, and the effects were saturated at 50 microM. Ca2+ (5.0-50 microM) and/or the Ca2(+)-binding protein regucalcin (2.0 microM) did not have an appreciable effect on UDP-glucuronyltransferase and beta-glucuronidase activities in hepatic microsomes. Thus, Zn2+ and Cd2+ uniquely increased beta-glucuronidase activity. The Zn2(+)- and Cd2(+)-induced increase in beta-glucuronidase activity was completely reversed by the presence of an SH group-protecting reagent (dithiothreitol). The response of the microsomal enzyme to Zn2+ and Cd2+ (20 microM) was no longer seen after treatment with 0.2% Triton X-100 [polyoxyethylene(10)octylphenyl ether], indicating that the stimulation by these metals is dependent on membrane association. The present study suggests that, of various metals tested, Zn2+ and Cd2+ can uniquely increase hepatic microsomal beta-glucuronidase activity and that their effect is based on binding to membranous SH groups, beside the enzyme protein.
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PMID:Effects of Ca2+, Zn2+ and Cd2+ on uridine diphosphate-glucuronyltransferase and beta-glucuronidase activities in rat liver microsomes. 211 Aug 67

Both ethanol abuse and protein deficiency result in pancreatic injury. Moreover, these two variables frequently coexist. As lysosomal enzymes may play a role in the initiation of pancreatic injury, the aim of this study was to determine the effects of ethanol consumption and protein deficiency on pancreatic lysosomal stability. For 3 weeks, male Sprague-Dawley rats were match-fed (in groups of four) isocaloric amounts of one of the following liquid diets: (1) protein-sufficient diet, (2) protein-sufficient diet containing ethanol as 36% of the total energy, (3) protein-deficient diet, and (4) protein-deficient diet containing ethanol as 36% of energy. Pancreatic lysosomal stability was assessed by determining (a) latency, as indicated by the percentage increase in lysosomal enzyme activity in pancreatic homogenate induced by Triton X-100, and (b) by the percentage of lysosomal enzyme remaining in the supernatant after sedimentation of the lysosomal pellet from the pancreatic homogenate. Protein deficiency was associated with a decrease in latency and an increase in supernatant enzyme. Ethanol administration was associated with a decreased latency. Both protein-deficient and ethanol-fed animals exhibited higher pancreatic activities of cathepsin B, a lysosomal protease capable of activating trypsinogen. In addition, protein-deficient animals exhibited higher pancreatic activities of acid phosphatase, N-acetyl-glucosaminidase, and beta-glucuronidase. As lysosomal enzymes are postulated to play a role in the initiation of pancreatitis, these results suggest that ethanol consumption and protein deficiency may at least partly exert their toxic effects on the pancreas by altering pancreatic lysosomal stability and increasing the glandular content of cathepsin B.
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PMID:Both ethanol consumption and protein deficiency increase the fragility of pancreatic lysosomes. 236 35

The purpose of this study was to compare the latencies of lysosomal enzymes (beta-glucuronidase, beta-N-acetylglucosaminidase, arylsulphatase and acid ribonuclease) in heart and in red and white skeletal muscle of male and female mice (Mus musculus). The unsedimentable, free activities together with releasable (Triton X-100, hypotonic shock and freeze-thawing treatments) and unreleasable, bound activities were assayed. The distribution of acid hydrolases to different fractions was strikingly heterogeneous. The most distinct differences occurred between the distributions of beta-glucuronidase and beta-N-acetylglucosaminidase. The differences between muscle types occurred in the activity levels of lysosomal enzymes, rather than in the fractional distributions. Sex-related differences were small and occurred mainly in the activity levels of heart muscle (higher in female mice). The results suggest that the heterogeneous distribution of lysosomal enzymes originates in the compartmental differences of lysosomal enzymes in muscle cells, rather than the differences in cell populations of different muscle types.
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PMID:Latency differences of lysosomal enzymes in cardiac and skeletal muscles of male and female mice. 286 81

A previously validated small mammal trauma model, hind-limb ischemia secondary to infrarenal aortic ligation in the rat, was utilized to investigate the effects of traumatic injury on hepatic glucuronidation activity. As was previously observed with hepatic oxidative drug metabolism, model trauma resulted in a significant decrease in the in vivo glucuronidation of chloramphenicol, with a 23% drop in clearance of this drug. The effect on in vivo pharmacokinetics appeared to result from a complex interaction between trauma's differential influences on conjugating enzyme(s), deconjugating enzyme(s), and hepatic UDP-glucuronic acid levels, as well as the relative physiological importance of these variables. Hepatic UDP-glucuronyltransferase activities towards both p-nitrophenol and chloramphenicol were elevated (44-54%) after model injury when measured in native hepatic microsomes. However, microsomes which had been "activated" by treatment with Triton X-100 showed no significant difference between control and traumatized animals. Serum beta-glucuronidase activities were elevated by 58%, while hepatic beta-glucuronidase rose by about 16%. Nevertheless, in vivo deconjugation showed no significant change. Model trauma also resulted in a 46% decrease in hepatic UDP-glucuronic acid content. Thus, the observed post-traumatic depression of in vivo chloramphenicol glucuronidation could be due either to a diminished availability of a necessary cofactor (UDP-glucuronic acid) or to an alteration in enzyme kinetics or function in vivo.
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PMID:Effects of model traumatic injury on hepatic drug metabolism in the rat. IV. Glucuronidation. 286


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