Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.21 (beta-glucosidase)
 3,280 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Zymosan (Z) and its major insoluble carbohydrate component beta-linked glucan activate human neutrophils (PMN) through a trypsin-sensitive recognition mechanism. This mechanism is believed to involve the PMN CR3R. Both Z and glucan generated dose and time-dependent release of the secondary lysosomal granule marker vitamin B12 binding protein, leukotriene B4 (LTB4) and superoxide from PMN and were phagocytosed with similar dose-dependent kinetics. The PMN superoxide and LTB4 responses to glucan; however, were consistently greater than those to the same doses of Z. The phagocytosis of both particles was significantly reduced after partial digestion with beta-laminarinase but not beta-glucosidase or alpha-mannosidase suggesting a recognition mechanism dependent on intact beta-1,3-glucosidic bonds in both particles. TNF-alpha (rhTNF-alpha) promoted a time- and dose-dependent increase in the expression of PMN CR3 up to 60 min. The increased expression of CR3 was paralleled by the release of the secondary lysosomal granule marker vitamin B12-binding protein. This granule contains a population of CR3R in its boundary membrane and it is the fusion of this membrane with the plasma membrane that may represent the mechanism by which CR3 expression is increased. Preincubation of PMN with 10(-9)M rhTNF-alpha augmented phagocytosis, LTB4, and superoxide generation by PMN in response to activation by Z. In contrast, none of the responses to glucan was significantly increased after incubation with rhTNF-alpha. These differences suggest a lack of absolute homology between the recognition mechanisms for zymosan and glucan and that there is a component of the recognition mechanism for zymosan that is independent of that for glucan and is up-regulated after rhTNF-alpha pretreatment.
 ...
PMID:Differential augmentation by recombinant human tumor necrosis factor-alpha of neutrophil responses to particulate zymosan and glucan. 215 33

To elucidate a possible mechanism for the anti-inflammatory action of iridoid glycosides, the effects of both aucubin (AU) and its hydrolyzed product (H-AU) by beta-glucosidase treatment were studied on the production of TNF-alpha in RAW 264.7 cells. H-AU suppressed the production of both mRNA for TNF-alpha and subsequent TNF-alpha protein in the culture, but AU did not. The production of TNF-alpha protein was inhibited in a dose-dependent manner with an IC (50) of 9.2 microM. In addition, treatment with H-AU blocked both the I-kappa B alpha degradation and the translocation of NF-kappa B from the cytosol fraction to the nuclear fraction (55 % inhibition) in the culture. However, treatment with H-AU did not affect the intracellular level of cAMP formed by forskolin treatment in human monocytes U937 culture, implying that there is no influence on the cAMP level in other cell systems. The present study indicates a possible justification for those medicinal plants containing iridoid glycoside that have been used for the treatment of inflammation.
 ...
PMID:Anti-inflammatory activity of aucubin by inhibition of tumor necrosis factor-alpha production in RAW 264.7 cells. 1532 52