Stobadine inhibits lysosomal enzyme release in vivo and in vitro

Objective: The aim of this study was to evaluate the in vitro immunomodulatory activity of aqueous and ethanolic extract of dried tubers of Eulophia nuda.Methods: Effect of both the extracts was evaluated at various concentrations (832–6.5 μg/ml) for secretion of mediators such as nitric oxide (NO), superoxide, lysosomal enzyme, and myeloperoxidase activity of isolated murine peritoneal macrophages.Results: The extracts showed stimulation of NO, statistically significant at 832 μg/ml (SI 1.739) for ENA and at 832 μg/ml (stimulation index [SI] 1.662) for ENE; significant stimulation on lysosomal enzyme release for ENA at 832 μg/ml (SI 1.404) and ENE at 832 μg/ml (SI 1.513); myeloperoxidase activity was statistically significant for ENA at 832 μg/ml (SI 1.728) and ENE at 832 μg/ml (SI 1.770).Conclusion: In vitro phagocytic index showed significant results and thus proving the need for confirmation through in vivo studies.

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Release of β-glucuronidase from peritoneal macrophages of normal and endotoxin-tolerant mice

Canadian Journal of Microbiology ◽

10.1139/m79-196 ◽

1979 ◽

Vol 25 (11) ◽

pp. 1245-1251 ◽

Cited By ~ 7

Author(s):

Stephen L. Snyder ◽

Sharyn K. Eklund ◽

Richard I. Walker

Keyword(s):

Lysosomal Enzyme ◽

Lysosomal Enzymes ◽

Lethal Dose ◽

In Vitro Release ◽

Peritoneal Macrophages ◽

Endotoxin Shock ◽

Enzyme Release ◽

Endotoxin Challenge

Lysosomal enzyme release from cells involved in inflammatory response could play a central role in the pathogenesis of endotoxin shock. Therefore we have studied the release of the lysosomal enzyme, β-glucuronidase, from peritoneal macrophages obtained from normal and endotoxin-tolerant B6CBF1 mice both before and after challenge with lethal doses of endotoxin. Unstimulated cells from tolerant mice spontaneously released a smaller percentage of their total β-glucuronidase content in culture than cells from normal mice during a 5-h incubation period. In support of the lysosomal enzyme release hypothesis, it was found that the in vitro release of β-glucuronidase was accelerated when cells were collected from the mouse peritoneum 3 h after i.v. challenge with a lethal dose (1.0 mg) of endotoxin. The increased in vitro "leakiness" of peritoneal macrophages following endotoxin challenge was less marked when tolerance was induced in mice by prior repeated injections of endotoxin. Furthermore, measurements of the total enzyme activities of peritoneal cells revealed a significant reduction in the β-glucuronidase content of cells from normal mice 3 h after endotoxin challenge but no such decrease for cells from tolerant mice. These results suggest that macrophages in endotoxin-sensitive mice release their lysosomal enzymes in vivo during endotoxemia, whereas cells found in tolerant mice do not.In related experiments, the phagocytosis of latex particles and inhibition of bacterial growth by macrophages from normal and tolerant mice were compared. These studies suggest that cells from tolerant mice may also release a smaller percentage of their lysosomal enzymes during phagocytosis.

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A Primer on In Vitro and In Vivo Cytosolic Enzyme Release Methods

Injectable Drug Development ◽

10.1201/b14378-11 ◽

1999 ◽

pp. 155-175

Keyword(s):

Enzyme Release

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Monoclonal antibody AHN-1 inhibits phagocytosis by human neutrophils

Blood ◽

10.1182/blood.v65.2.333.bloodjournal652333 ◽

1985 ◽

Vol 65 (2) ◽

pp. 333-339

Author(s):

KM Skubitz ◽

DJ Weisdorf ◽

PK Peterson

Keyword(s):

Monoclonal Antibody ◽

Lysosomal Enzyme ◽

Surface Proteins ◽

Superoxide Production ◽

Human Neutrophils ◽

Enzyme Release ◽

Specific Monoclonal Antibody ◽

Normal Human ◽

Major Surface

The granulocyte-specific monoclonal antibody, AHN-1, immunoprecipitates two major surface-iodinated proteins of 105,000 and 145,000 to 150,000 daltons from normal human neutrophils. In this study, the effect of AHN- 1 on a number of neutrophil functions was evaluated in vitro. Both complement- and antibody-mediated phagocytosis were inhibited when human neutrophils were pretreated with AHN-1 and opsonized bacteria were used as targets. The inhibition of phagocytosis was specific, in that lysosomal enzyme release and chemotaxis were not altered by treatment with AHN-1. AHN-1 did inhibit superoxide production by neutrophils in response to particulate stimuli, but not in response to the soluble stimulus, 12-O-tetradecanoylphorbol-13-acetate. The data indicate that one or both of these surface proteins may be important in the process of phagocytosis. AHN-1 should be useful in isolating and further characterizing the nature of these molecules.

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Bradykinin stimulates bone resorption and lysosomal-enzyme release in cultured mouse calvaria

Biochemical Journal ◽

10.1042/bj2190329 ◽

1984 ◽

Vol 219 (1) ◽

pp. 329-332 ◽

Cited By ~ 35

Author(s):

G T Gustafson ◽

U Lerner

Keyword(s):

Bone Resorption ◽

Bone Tissue ◽

Lysosomal Enzyme ◽

Enzyme Release ◽

Newborn Mouse ◽

Mouse Calvaria ◽

Stable Calcium

The effect of bradykinin on bone resorption was studied in cultures of newborn-mouse calvaria. Bradykinin (0.03 microM, 1 microM) stimulated the release of 45Ca2+ from bones dissected out from mice prelabelled in vivo with 45Ca. Bradykinin (1 microM) also augmented the release of stable calcium (40Ca), Pi and the lysosomal enzyme beta-glucuronidase. The stimulatory effect of bradykinin on mineral mobilization and lysosmal -enzyme release could be blocked by indomethacin. It is speculated that concomitant generation of thrombin and bradykinin in areas of trauma and inflammation may induce resorption of nearby bone tissue.

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