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)

Human alveolar macrophages specifically released lysosomal beta-glucuronidase and neutral proteases when successively incubated with IgE, and then, for 30 min, with anti-IgE. Superoxide anion O2- generation was obtained when anti-IgE-opsonized zymosan was added to IgE-incubated cells. Macrophages from smokers excreted twice as much enzymes and superoxide as cells from non-smokers. It was possible to induce the specific release of beta-glucuronidase with normal alveolar macrophages successively incubated with the serum of patients allergic to house dust or to grass pollen and then with the specific allergen. This characteristic opens the field to a direct test for allergic sera by analogy with the allergen-induced degranulation test of sensitized basophils.
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PMID:Enzyme release and superoxide anion production by human alveolar macrophages stimulated with immunoglobulin E. 625 6

We have shown that IgG hydrolysed by Schistosoma mansoni schistosomula inhibited various macrophage functions, especially phagocytosis and anti-schistosome cytotoxicity. Here we show that a tripeptide, Thr289-Lys-Pro291, of the second constant domain of human immunoglobulin G (peptide 286-292) reproduced the inhibitory effect of a total hydrolysate. Indeed the beta-glucuronidase release from IgE-anti-IgE-stimulated rat and human macrophages decreased and its intracellular level did not rise after a prior incubation of the cells with Thr-Lys-Pro (500 nmol/ml). Moreover, the cell migration as well as the superoxide anion O2 generation were 50-80% reduced by the tripeptide. These results suggest that a single peptide set may be responsible for the decrease of the macrophage functions at the early stage of the parasite infection in the mammalian host. The pharmacologic properties of this tripeptide are under investigation.
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PMID:Characterization and synthesis of a macrophage inhibitory peptide from the second constant domain of human immunoglobulin G. 629 3

Platelet-activating factor (PAF) is a mediator of a anaphylaxis found initially in basophils and later in mouse and rat macrophages. The purpose of this paper was to determine the cellular origin of PAF released from human leucocytes and to establish if phagocytosis is a more important stimulus for PAF release than anaphylactic reactions. Phagocytic leucocytes (monocytes and PMNs) released PAF, physicochemically analogous to the PAF obtained by anaphylactic reactions in rabbits when challenged with zymosan, zymosan coated with complement, immune complexes, immunoglobulin aggregates or calcium ionophore A23187. Basophils failed to release PAF by anti-human IgE antibody, although positive degranulation and histamine liberaton were found. Pre-incubation of phagocytosing leucocytes with cytochalasin B or colchicine produced a diminution of PAF release, whereas beta-glucuronidase liberation was increased. The addition of carboxypeptidase B did not significantly modify PAF or beta-glucuronidase release. These data indicate that PAF obtained from preparations of human leucocytes comes from monocytes and polymorphonuclears; human basophils do not liberate measurable quantities of PAF, either by anaphylactic stimulus or by neutrophil cationic proteins; liberation of PAF and lysosomal content follow different mechanisms as they have different kinetics and are modified in an opposite way by drugs acting on the cytoskeleton.
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PMID:Platelet-activating factor in anaphylaxis and phagocytosis. I. Release from human peripheral polymorphonuclears and monocytes during the stimulation by ionophore A23187 and phagocytosis but not from degranulating basophils. 677 37

Peripheral blood leukocytes from fifteen patients with atopic dermatitis and ten normal nonatopic volunteers were incubated with various stimuli in vitro, and the release of the lysosomal beta-glucuronidase into the supernatant was measured. beta-Glucuronidase release was significantly reduced in patients with severe atopic dermatitis after stimulation with aggregated IgG, horse antihuman lymphocyte globulin (ALG), zymosan, and yeast-activated serum. There was an indirect correlation (r = -0.83) between aggregated IgG-induced beta-glucuronidase release and the intensity of clinical symptoms; however, there was no correlation with serum IgE levels. The enzyme release measured was not caused by cellular lysis, except for high concentrations of antilymphocyte globulin, as determined by lactic dehydrogenase (LDH) activity in the supernatant. It is concluded that lysosomal enzyme release defects might be involved in the well-known decreased resistance to infections in patients with atopic dermatitis.
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PMID:Decreased release of lysosomal enzymes from peripheral leukocytes of patients with atopic dermatitis. 683 38

beta-Hexosaminidase, beta-glucuronidase, arylsulfatase, and tryptase were each released along with histamine from dispersed purified human lung mast cells of 40 to 80% purity by rabbit IgG anti-human IgE. The net per cent release ratio of each enzyme to histamine was determined over all doses of antibody employed to activate the mast cells and over all time points after activation, and indicated the per cent of each enzyme stored in secretory granules along with histamine. By multiplying the net per cent release ratio of each enzyme to histamine by total enzyme content in a preparation of 10(6) mast cells, values for secretory granule content per 10(6) mast cells were found to be 3.8 U for beta-hexosaminidase, 0.03 U for beta-glucuronidase, 0.03 U for arylsulfatase, and 0.9 U for tryptase. Subtype analysis of beta-hexosaminidase by diethylaminoethyl- (DEAE) cellulose chromatography revealed that the B isomer predominates in human mast cell secretory granules, whereas the A isomer predominates in secretory granules of the rat mast cell. Tryptase, the predominant neutral protease of the human mast cell secretory granule, has a m.w. of 130,000 by gel filtration chromatography, whereas the major neutral protease of the rat mast cell is chymotryptic and of 25,000 m.w. The presence of acid hydrolases, a tryptase, and histamine in human mast cell secretory granules suggests that the activated mast cell plays a direct role in the production of acute and subacute inflammation.
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PMID:Acid hydrolases and tryptase from secretory granules of dispersed human lung mast cells. 700 36

The aim of this study was to evaluate the efficacy and safety of enzyme-potentiated desensitization (EPD) in children with asthma. Twenty asthmatic children (14 males and 6 females; median age: 8.5 years) were included in the study. They had positive skin tests to Dermatophagoides pteronyssinus (Dpt), no history of other allergy and had suffered from asthma for at least two years. The children were examined before starting the trial, at the first EPD dose, after 8 weeks, at the second EPD dose and 3 months after the second EPD dose. Blood samples for PRIST and RAST were drawn before the first and at the second EPD dose, and at the last follow-up. Conjunctival provocation tests (CPT) and skin test endpoint determinations were performed with dilutions of a freeze-dried Dpt extract (10-100,000 SQ-U/ml) at the start of the trial and at the last follow-up. Parents kept a diary record of the days with asthma and daily drug usage. The children were randomized to receive either two intradermal placebo injections or the active material with an 8-week interval (November 1991 and January 1992). Ten children received EPD and 10 children placebo. The intradermal injection of EPD (0.05 ml) contained 0.01 ml of beta-glucuronidase (40 Fishman units) and 0.04 ml of a mixture of inhalant allergens (1 Noon unit). The placebo injection consisted of buffer solution only. The EPD-treated children had significantly fewer days with asthma (p = 0.00000). In addition, the EPD-treated children used significantly less medication for the management of asthma attacks (p = 0.00000). At the start of the trial, three out of 10 children in the EPD group and two out of 10 in the placebo group reacted only to the highest dose of allergen used in the CPT (100,000 SQ/ml) (NS). At the last follow-up, the threshold dose in the CPT was 100,000 SQ/ml or more in nine out of 10 children in the EPD group and in four out of 10 children of the placebo group (p = 0.0349). At the last follow-up, one child in the EPD group had a negative CPT with all doses tested. Global clinical evaluation by the investigators showed that eight out of 10 EPD-treated children improved, in comparison with three out of 10 children in the placebo group (p = 0.0349). Assessment by the parents was six out of 10 and four out of 10 improved, respectively (NS). Specific IgE to Dpt, total IgE and skin prick test endpoints before and after EPD showed no significant changes. One child in the placebo group experienced mild urticaria several hours following the second injection. No other local or systemic side effects were reported. The results of the present study provide further data on the effectiveness and safety of EPD in patients with asthma.
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PMID:Enzyme-potentiated desensitization in children with asthma and mite allergy: a double-blind study. 884 6

Tectoridin isolated from the flowers of Pueraria thunbergiana (Leguminosae) are metabolized to tectorigenin by human intestinal microflora. When tectoridin was orally administered to rats, tectorigenin, but not tectoridin, was detected in urine after beta-glucuronidase hydrolysis. The main metabolite tectorigenin potently inhibited the passive cutaneous anaphylaxis reaction and inhibited in vitro the release of beta-hexosaminidase from RBL-2H3 cells induced by IgE. These results suggest that tectoridin is a prodrug, which can be transformed into the active agent tectorigenin by human intestinal bacteria and can be a candidate for antiallergic agent.
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PMID:Passive cutaneous anaphylaxis-inhibitory action of tectorigenin, a metabolite of tectoridin by intestinal microflora. 1525 47

This unit describes methods for measuring exocytosis of preformed mediators from secretory granules as an indication of IgE receptor-mediated activation of mast cells. The first basic protocol describes the measurement of biogenic amines (serotonin and histamine) secreted by activated rodent mast cells (for serotonin) or rodent and human mast cells (for histamine). The second basic and alternate protocols detail techniques for measuring the release of beta-glucuronidase, an enzyme that is synthesized by human and rodent mast cells, stored in secretory granules, and released during degranulation. Methods for assaying other enzymes released during degranulation, such as beta-hexosaminidase and tryptase, are discussed in the . These protocols can also be applied to basophils where appropriate.
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PMID:Measuring degranulation of mast cells. 1843 37


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