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)

Pigment gallstones are defined as any dark brown-to-black stone, consisting of calcium salts of bilirubin, phosphate, carbonate and other anions, and can be separated into carbonate- and noncarbonate-containing groups. Pigment stones predominate in the rural Orient, in cirrhosis, and in elderly United States patients undergoing cholecystectomy. Clinical associations include bile duct obstruction, stasis, and possibly hemolysis. Of pigment stones, 50% are radioopaque and account for two-thirds of all opaque stones. The concentrations of bile salts, phospholipids,, cholesterol, and total bilirubin in bile are similar to normal levels, but the concentration of unconjugated bilirubin is increased in the bile of some patients. Increased unconjugated bilirubin in bile may be caused by increased hydrolysis of excreted conjugated bilirubin. Unconjugated bilirubin is solubilized by bile salts, but the interaction is primarily nonmicellar. Ionized calcium and pH are important determinants of solubility. Sulfated glycoproteins, excreted in increased amounts in patients with cholelithiasis, may be the site of pigment stone precipitation because these compounds bind calcium salts tightly. E coli is frequently cultured from pigment stones in Japan but not in the United States; thus, bacterial beta-glucuronidase may be important in stone formation in Japan but probably not in the West. Stasis leads to increased calcium secretion and to increases in the concentration of sparingly soluble compounds that may then precipitate. Incomplete emptying of the gallbladder may result in the same concentration process. Unsaturated fats and chronic vagal stimulation cause pigment stone formation in animals. At present, surgery is the only treatment for pigment lithiasis.
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PMID:Pigment gallstones. 31 81

The authors reported previously that beta-glucuronidase in bile, especially during biliary infection with Escherichia coli, plays a substantial role in producing cium bilirubinate gallstones. In the present study, bile levels of glucaro-1:4-lactone (measured as glucaric acid) the leading inhibitor of beta-glucuronidase, were measured in both man and in rats fed high, medium, and low protein-fat diets. Glucaric acid and total bilirubin in bile correlated well in human controls but not in gallstone patients. In animal experiments, the levels of these substances in bile were high in rats on high protein-high fat and low in those on low protein-low diets. These data suggest that when bile is infected with E. coli, calcium bilirubinate gallstones seemed to form more easily in patients on low protein-low fat diet than in those consuming food rich in protein and fat. On the other hand, the ratio of lecithin to cholesterol was higher in low protein-low fat rats than in high protein-high fat rats, suggesting that cholesterol gallstones were more likely to form on the latter diet. The animal, clinical, epidemiological, and dietary data are consistent with the known trend to a decreased incidence of calcium bilirubinate and an increased incidence of cholesterol gallstones in Japan.
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PMID:Effects of diet on glucaric acid concentration in bile and the formation of calcium bilirubinate gallstones. 32 83

We have developed and optimized an enzyme-linked immunosorbent assay (ELISA) for absolute quantitation of human beta-glucuronidase. This is a double antibody sandwich system employing two murine monoclonal antibodies specific for human beta-glucuronidase developed in our laboratories. The method involves (a) coating of the high binding polystyrene microtitration plate with the first antibody (7B6 IgG), (b) blocking of remaining active sites with 3% bovine serum albumin in phosphate-buffered saline, (c) application of samples, (d) addition of the biotinylated second antibody (6D2 IgG), (e) addition of streptavidin-horseradish peroxidase, and (f) development of color with o-phenylenediamine dihydrochloride-H2O2 and reading in a microplate reader at a wavelength of 490 nm. The method is highly sensitive with an optimal range of 10 to 100 ng/ml of the enzyme and is reproducible with intraday and interday precisions of 3.2 and 4.1%, respectively. The enzyme contents of 20 urine and 20 bile samples quantitated by this ELISA method were, respectively, 148 +/- 101 and 6380 +/- 3780 ng/ml (means +/- SD) which correlated well with their enzyme activities. Such a method for absolute quantitation of human beta-glucuronidase is essential for studying its pathophysiologic roles in cholelithiasis and carcinogenesis and can also be used clinically as an indicator for tissue damage or malignancy.
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PMID:Development and optimization of an enzyme-linked immunosorbent assay employing two murine monoclonal antibodies for absolute quantitation of human beta-glucuronidase. 141 87

We intend to purify beta-glucuronidase from human liver in a large quantity in order to facilitate the study of its biochemical structure and pathophysiologic roles in cholelithiasis and carcinogenesis. The initial purification procedure involved: (1) liver homogenization, (2) 25-45% saturated ammonium sulfate fractionation, (3) heat denaturation of protein at 56 degrees C, (4) gel filtration with Bio-Gel P-300 gel, (5) anion exchange chromatography with DEAE agarose, (6) cation exchange chromatography with CM agarose, and (7) hydroxyapatite chromatography (overall yield, 1%; overall purification, 169X). The final product was used to immunize rabbits and BALB/c mice for production of polyclonal and monoclonal antibodies, respectively. The antibodies, mainly IgG, were purified by using gamma-Protein A agarose column chromatography. The purified IgG, after periodate oxidation, was coupled to hydrazide gel by formation of a stable covalent hydrazone bond linkage. The new purification procedure involved the initial first three steps, followed by (4) polyclonal IgG immunoaffinity chromatography and (5) monoclonal IgG immunoaffinity chromatography (overall yield, 6.1%; overall purification, 3720X). Polyacrylamide gel electrophoresis indicated minor contaminants in the final product which could be further purified by electroelution. It is concluded that beta-glucuronidase constitutes 0.016 mg per gram of wet liver tissue and can be obtained on a large scale in a highly purified form within a 2-day cycle.
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PMID:A large-scale purification of beta-glucuronidase from human liver by immunoaffinity chromatography. 177 14

We determined and compared the beta-glucuronidase (beta-G) activity among strains of B. fragilis and E. coli under the optimum condition. Results showed that the mean beta-G activity of strain B. fragilis ATCC25285 was 94.7u. B. fragilis ATCC25285 strain was selected as the model strain to establish the animal model of bilirubin gallstones because its beta-G activity was obviously higher than that of B. fragilis CDC14462 and E. coli 3362 (O157K88) strain.
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PMID:[Determination and comparison of beta-glucuronidase activity among strains of B. fragilis and E. coli]. 178 64

Cholelithiasis differs considerably from area to area in the world. Calcium bilirubinate stones or brown pigment stones are said to predominate in the Orient, however, this situation may differ within the Orient. In order to compare cases in China and Japan, 102 consecutive cases of cholelithiasis operated on in Shenyang, China were analyzed for the composition of gallstones and bacterial species isolated from bile in relation to the location and composition of gallstones. In Shenyang, calcium bilirubinate stones predominated, occurring in 49.0 per cent of the cholelithiasis cases. This was much higher than in Japan, which had 17.5 per cent. The incidence of bacteria was also very high, ranging from 20 to 96 per cent, with an average of 66.7 per cent depending on the kind of gallstone present. Bacterial species possessing beta-glucuronidase activity were present in nearly all the cases of calcium bilirubinate stones (92.0 per cent). The incidence of bacteria with beta-glucuronidase activity especially of E. coli was much higher than in Japan (50.8 per cent versus 21.8 per cent) in concordance with the higher incidence of calcium bilirubinate stones in China (49.0 versus 17.5 per cent).
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PMID:The bacteriology of cholelithiasis--China versus Japan. 178 7

A comparative study of Bacteroides fragilis and E. coli bacterial infection in the biliary tract in relation to the pathogenesis of pigment stone formation was carried out on the basis of gallstone rabbit's model of anaerobic bacterial infection. One hundred and twenty Japanese hybrid big-ear white rabbits were randomly divided into four groups: 14 in control group, 31 in B. fragilis (BF) group, 42 in E. coli group and 33 in the mixed group. In the experimental groups we successfully made gallstone formation in aerobic, anaerobic and mixed bacterial infections in biliary tracts respectively. On 7, 15 and 30 postoperative days the survival rabbits were sacrificed for investigations. Our experiments demonstrated that the incidence and amount of stone formation in the mixed group were the highest among the experiment groups. The key point to preclude stone formation was to control the bacterial infection in the biliary tract as early as possible. The results suggested that the ability of production of beta-glucuronidase in BF group was significantly higher than that in E. coli group. The author considered that BF was more important than E. coli in the pathogenesis of calcium bilirubinate gallstone formation.
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PMID:[A comparative study of Bacteroides fragilis and E. coli related to the pathogenesis of calcium bilirubinate gallstones]. 181 25

We have developed a simple, rapid method for purification of beta-glucuronidase from human liver in order to facilitate the study of its biochemical structure and pathophysiologic roles in both cholelithiasis and carcinogenesis. The procedure includes the following steps: (1) liver homogenization, (2) 25-45% saturated ammonium sulfate fractionation, (3) heat denaturation, and (4) immunoaffinity chromatography employing murine anti-human beta-glucuronidase monoclonal IgG binding to tresyl-activated agarose. beta-Glucuronidase constitutes 1.3 mg per 100 g of wet liver tissue. The enzyme can be purified with a 10% overall yield and overall purification of 5000-fold in a 2-day cycle on a fairly large scale by the method described. Polyacrylamide gel electrophoresis indicated minor contaminants in the final product which could be further purified by protein blotting.
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PMID:Rapid purification of beta-glucuronidase from human liver by immunoaffinity chromatography employing specific murine monoclonal IgG binding to tresyl-activated agarose. 182 73

Black and brown pigment gallstones are morphologically, compositionally, and clinically distinct. Black stones form primarily in the gallbladder in sterile bile and are associated with advanced age, chronic hemolysis, alcoholism, cirrhosis, pancreatitis, and total parenteral nutrition. Brown stones form not only within the gallbladder but also within the intrahepatic and extrahepatic ducts; they are uniformly infected with enteric bacteria and are usually associated with ascending cholangitis. Brown stones are related to juxtapapillary duodenal diverticula and are the predominant type of de novo common bile duct stones. Cholecystectomy is usually curative in black pigment stone disease, whereas stones often recur after cholecystectomy for brown stone disease. The pathogenesis of black stones is probably related to nonbacterial, nonenzymatic hydrolysis of bilirubin conjugates. At the pH of bile, this results in two monohydrogenated bilirubin anions that precipitate with calcium ions. Bilirubin monoconjugates that are increased in several conditions, such as Gilbert's syndrome and chronic hemolysis, may play a pivotal role in black stone formation as a source of unconjugated monohydrogenated bilirubin and as a possible co-precipitant with calcium. The precipitation of calcium carbonate and phosphate is influenced by local gallbladder factors. Brown pigment stones are formed in bile infected with enteric bacteria that elaborate hydrolytic enzymes: beta-glucuronidase, phospholipase A, and conjugated bile acid hydrolase. The resulting anions of bilirubin and fatty acids form insoluble calcium salts. We used nb/nb mice with a chronic hemolytic anemia as a model of hemolysis-induced black stone disease. The presence of 40% bilirubin monoconjugates in mouse gallstones indicated the importance of this moiety in the pathogenesis of black stones. Other data obtained by marrow transplantation experiments in mice revealed the relative importance of genotype versus the hemolytic anemia on determinants such as biliary bile acid composition and mucin secretory glands in the mouse gallbladder neck. Additional physical chemical studies of the interaction of unconjugated bilirubin in model bile solutions will be helpful in further delineating the pathogenesis of both black and brown pigment gallstones.
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PMID:Pigment gallstone disease. 202 17

This article presents the changes in the concentration of bilirubin, cholesterol, phospholipid, bile acid and the activity of bacterial beta-glucuronidase in hepatic bile of rabbits infected with metacercariae of Clonorchis sinensis. We found that the activity of bacterial beta-glucuronidase was significantly higher in the infected group (52.6 +/- 31.6 u/dl) than that in control rabbits (12.5 +/- 20.5 u/dl) (P less than 0.001), and no marked changes in the concentration of bilirubin, cholesterol, phospholipid and bile acid were found. concentration of bilirubin, cholesterol, phospholipid and bile acid were found. By using alcian blue-PAS combined stain method the authors also noticed that the amount of glycoprotein in goblet cells has considerably increased and secreted increasingly to the biliary duct after infection with Clonorchis sinensis. As the increase in bacterial beta-glucuronidase activity and glycoprotein in bile is in favour of the formation of pigment stone, this may explain why clonorchiasis is often complicated with cholelithiasis.
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PMID:[Changes in bile composition in rabbits infected with Clonorchis sinensis]. 219 93


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