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PubMed1991

Zymosan-induced chemiluminescence of alveolar macrophages: depression by inorganic dust constituents.

A method has been developed which allows the incubation of alveolar macrophages as weakly affixed monolayers in siliconized glass dishes. Without vigorous mechanical agitation and without using proteolytic enzymes, these cells were subsequently transferred to cuvettes where the zymosan-stimulated chemiluminescence of the suspended cells was measured. In vitro incubations of activated rabbit alveolar macrophage monolayers with airborne dusts from four West German sites (1 to 200 micrograms/10(6) cells), fly ash fractions of a special waste incinerator at Hamburg (50 to 1,000 micrograms/10(6) cells), and quartz dust DQ 12 (5 to 200 micrograms/10(6) cells) resulted in a dose- dependent depression of the zymosan-stimulated chemiluminescence. The depression of chemiluminescence was correlated with particle numbers, estimated dust surface, and antimony and lead masses of the dusts to which the cells were exposed. Cytotoxicity was better correlated with these parameters than with dust mass.

Animals↗

PubMed1982

Opsonic activity against zymosan of normal human serum of different blood types.

Serum opsonic activity against zymosan was found to be decreased more markedly in highly diluted O type serum than in the other 3 types, among which no difference was noted. Heat-killed bacteria were equally well opsonized with any type of serum. This peculiar activity of O type serum against zymosan was not affected by the removal of isohemagglutinins. No inhibitory activity was demonstrable in O type serum.

ABO Blood-Group System↗

PubMed2005

Nitric oxide prevents the bacterial translocation and inhibits the systemic inflammatory response produced by implantation of a vascular prosthesis followed by Zymosan A.

OBJECTIVE AND DESIGN: To evaluate the beneficial effects of exogenous NO and its levels of action in a model of SIRS/Bacterial Translocation (BT) induced by two sequential insults. MATERIAL OR SUBJECTS: Eighty-six Wistar rats were submitted to different treatments and their tissue and blood samples were accessed at the end of the experiment. TREATMENT: Nitric Oxide was compared to Gentamicin as the tested guideline for our study. METHODS: Dacron graft implantation (first insult) and subsequent administration of Zymosan A((R)) (second insult) were performed in Wistar rats. The animals were divided into 6 groups: I) No manipulation (BASAL: ); II) Laparotomy (L) + mineral oil (SHAM: ); III) L + Graft-Zymosan (GZ) (CONTROL: ); IV) L + GZ + Antibiotic (A) (ASSAY: I); V) L + GZ + NO (ASSAY: II) and VI) L + GZ + A + NO (ASSAY: III). Determinations: Survival, Bacterial Translocation, myeloperoxidase (MPO), Cytokines (TNF-alpha, IL-1beta, IFN-gamma), Oxygen Free Radical (OFR) SOA and detoxifying enzymes (SOD, Superoxide Dismutase, CAT, Catalase and GPX, Glutathione Peroxidase), Cell Adhesion Molecules, CAMs (ICAM-1, VCAM-1 and PECAM-1) and Nuclear Transcription Factor, NFkappaB. RESULTS: The model established induced a mortality rate of 20% and generated BT in all samples. It also significantly increased all variables, with P < 0.001 for MPO and all Cytokines; P < 0.01 for all OFR, and P < 0.05 for CAMs and for NFkappaB. Treatment with A reduced mortality to 0%, significantly decreased BT, MPO, Cytokines and OFR (P < 0.05), but did not reduce CAMs or NFkappaB. NO, either alone or associated, reduced mortality to 0% and abolished BT, significantly decreasing nearly all the variables studied (P < 0.001 for MPO and all Cytokines; P < 0.01 for OFR, and P < 0.05 for CAMs and for NFkappaB). CONCLUSIONS: The exogenous administration of NO before the two sequential insults prevented BT and controlled SIRS peripherally and at both cellular and transcriptional level in a lasting manner. In contrast, antibiotic treatment only exerted its action at peripheral level. The association of both treatments did not provide any important advantages.

Animals↗

PubMed1991

Single pulses of cytoplasmic calcium associated with phagocytosis of individual zymosan particles by macrophages.

We have measured cytosolic free calcium levels ([Ca++]i) in individual macrophages during the phagocytosis of single zymosan particles. We report here that the contact of a macrophage with zymosan results in a rapid transient elevation of [Ca++]i. Each [Ca++]i pulse is symmetrical lasting for up to 30 seconds. In contrast, macrophage spreading is associated with repetitive [Ca++]i spiking occurring in salvos of up to four smaller spikes, each lasting for between 8 and 18 seconds. These qualitative and kinetic differences might suggest that the role of [Ca++]i in phagocytosis is distinct from its role in spreading.

Animals↗

PubMed1984

Enhancement of IGE-induced mediator release from rat peritoneal mast cells by serum-treated zymosan.

Phagocytosis of zymosan (Z) treated with rat serum (ZX) by rat peritoneal mast cells caused only a small amount of [3H]serotonin release, and prior release of mediators from mast cells did not affect phagocytosis of sheep erythrocytes bearing IgG and C3b, indicating the independence of these two phenomena. When, however, mast cells were exposed to ZX, subsequent IgE-mediated release of histamine, [3H]serotonin, and beta-hexosaminidase was greatly enhanced. Prevention of complement activation by the presence of EDTA during the treatment of Z with the serum or prior heating of the serum at 56 degrees C for 30 min only slightly impaired the ability of ZX to augment mediator release, whereas prior absorption of the serum with zymosan at 0 degree C greatly diminished the enhancement. Exposure of fresh Z to variable amounts of either the acid or the high-salt eluate of ZX also generated ZX capable of enhancing [3H]serotonin release in a dose-dependent fashion. IgG, IgM, C3, and albumin were detected in the eluates by immunodiffusion. When IgG was depleted from the high-salt eluate by treating with Sepharose-anti-IgG, the enhancement was significantly reduced, indicating that IgG but not C3 or other immunoglobulins was required for the enhancement.

Animals↗

PubMed1984

Arachidonic acid-mediated and serum-opsonized-zymosan-mediated inhibition of complement production by macrophages. Lack of requirement for endogenous arachidonic acid metabolites.

The ability of exogenous prostaglandins to inhibit complement production (CP) by monocytes and macrophages (M phi) suggests that endogenous arachidonic acid metabolites produced by these cells may also regulate their rate of CP. We assessed the regulatory influence of endogenous metabolites on CP by M phi utilizing exogenous arachidonic acid and serum-opsonized zymosan as stimulators of production of cyclooxygenase and lipoxygenase metabolites. The results of this study show that (i) the inhibition of CP caused by both agents is is independent of arachidonic acid metabolites, suggesting that endogenously produced metabolites do not influence CP, and (ii) arachidonic acid and serum-opsonized zymosan inhibit production by independent mechanisms.

Animals↗

PubMed1988

Activation of B lymphocytes with human serum-treated zymosan.

C3 fragments fixed on zymosan particles were presented to resting human B lymphocytes. The opsonized zymosan (Ops-Z) particles induced release of leukocyte migration inhibitory factor, a slight decrease in mIgD, and a slight increase in the activation marker Blast-2. The B cells did not proceed further along the pathway of activation: they did not respond to B cell growth factor (BCGF) and Ops-Z did not synergize with other activators for BCGF response either. Thus, we found that interaction between C3 fragments and CR2 initiates the activation of human B lymphocytes, but this is limited to the early phase.

Antigens, Surface↗

PubMed1988

Monoclonal antibodies against the major zymosan-induced chemotactic factor in rabbit serum.

The major zymosan-induced chemotactic factor in rabbit serum was purified by a two-step ion exchange chromatography procedure. The purified chemoattractant was used as antigen for production of murine monoclonal antibodies against the major chemotactic factor. The primary screening of the hybridoma cultures was an indirect ELISA using purified chemotactic factor as antigen. The final selection among ELISA-positive clones was performed according to the results obtained in a chemotactic inhibition assay. Six monoclonal antibodies were raised. These antibodies completely abrogated or substantially reduced the chemotactic activity in crude zymosan-activated serum. The chemotactic factor(s) could be absorbed onto an immunosorbent column containing monoclonal antibody and subsequently be specifically eluted with acid. By Western blot analysis the molecular weight of the major chemotactic factor was estimated to be approximately 15,000, and isoelectric focusing indicated a pI of about 9.4.

Animals↗

PubMed1994

A new method for studying the binding and ingestion of zymosan particles by macrophages.

One of the major problems encountered during quantitative studies of phagocytosis is the discrimination without ambiguity between intracellular and extracellular particles. This difficulty is especially acute when zymosan particles are used because of their poor affinity for dyes. We show in this paper that zymosan particles may be stained by a mixture of a basic dye and tannic acid in water (or in an isotonic non saline solution). Crystal violet is one of the most suitable dyes and by combining this staining step with May-Grünwald Giemsa staining, it was possible to observe two populations of macrophage-associated particles. One comprises blue violet particles (BVP), and the second consists of particles with a purple-stained core (PPC). Treating macrophages in culture with various concentrations of cytochalasin B decreases the number of PPC and increases the number of BVP, in a dose dependant manner. Moreover, treatment with alpha-mannan or laminarin decreases the number of cell-associated particles, especially that of PPC. From these observations we concludes that BVP are extracellularly located and PPC are ingested.

Animals↗

PubMed1986

Species variability in the cardiovascular and hematologic effects of zymosan-activated plasma infusion.

The anaphylatoxins have been implicated in the pathogenesis of endotoxin shock and the adult respiratory distress syndrome. Both endotoxin and zymosan activate the complement pathway. Because there are marked species differences in the cardiovascular and hematologic effects of endotoxin infusion, the purpose of this study was to compare the effects of zymosan-activated plasma (ZAP) infusion in dogs, sheep, and baboons. ZAP was infused (0.11 ml/kg/min for 60 min) into dogs (n = 5), baboons (n = 5), and sheep (n = 3). The infusion of ZAP resulted in significant changes in heart rate (HR) (P less than 0.03), mean arterial pressure (MAP) (P less than 0.002), pulmonary artery pressure (PAP) (P less than 0.004), cardiac index (CI) (P less than 0.034), and extra vascular lung water (EVLW) (P less than 0.001). A specific difference between the species' response to ZAP infusion was present when evaluating the effect of ZAP on MAP (P less than 0.02), HR (P less than 0.003). EVLW (P less than 0.001), platelet count (P less than 0.01), and white blood cell count (P less than 0.01). The main species differences in the changes in MAP, HR, and platelet count were an increase in MAP, decrease in HR, and decrease in platelet count that occurred in dogs. The species difference in the WBC count was the result of ZAP-induced neutropenia in sheep versus a leukocytosis in dogs. Unlike dogs and baboons, sheep developed an increase in EVLW. Like endotoxin, the cardiovascular and hematologic effects of ZAP infusion are species dependent.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

Zymosan-induced arthritis in rats. II. Effects of anti-inflammatory drugs.

As zymosan-induced arthritis in rats combines dual activation of early prostaglandin-dependent processes (edema, fever, pain) and IL-1 related effects on cartilage metabolism, we compared the respective influences of indomethacin (IMT) and dexamethasone (DEX) on its course. Different parameters were assessed: knee swelling, febrile response, loss of activity, cartilage metabolism and histology. DEX improved all these parameters, while IMT exerted only light beneficial effects on fever and knee swelling without obvious beneficial influence on cartilage metabolism and histological lesions. These results suggest that anti-inflammatory activities of DEX and IMT are due to interferences with different pathways during zymosan-induced arthritis in rats.

Animals↗

PubMed1992

Opsonized zymosan decreases cytoplasmic motility of alveolar macrophages in dogs.

To examine the mechanisms of changes in alveolar macrophage (AM) activities caused by phagocytic stimulus, we studied the effect of opsonized zymosan (OZ) on cytoplasmic motility (CM) of AM from dog lungs in vitro. Four days after the instillation of ferrimagnetic particles (Fe3O4, 3 mg/kg) into the lower lobe bronchus, AM were harvested by broncho-alveolar lavage. AM were adhered to the bottom of plastic vials (10(6) cells of AM per each vial). Remanent field strength (RFS) from the AM containing Fe3O4 particles was measured immediately after magnetization. RFS decreased with time due to particle rotation (relaxation), which is related to cytoplasmic motility of AM. OZ (1-500 micrograms) decreased lambda 0 (the relaxation rate for the first min) in a concentration-dependent fashion. Neither BW755C (10(-5) M), indomethacin (10(-6) M), leupeptin (10(-5) M), bestatin (10(-5) M), nor superoxide dismutase (1000 U/ml) inhibited OZ (500 micrograms)-induced inhibitory effects on lambda 0, suggesting that cyclooxygenase and lipoxygenase products, serine, thiol enzymes, aminopeptidase and superoxide anion wer not responsible for OZ-induced effects. OZ (500 micrograms) significantly increased the intracellular concentration of Ca2+ (P less than 0.01). Likewise, OZ (500 micrograms)-induced effects on lambda 0 of AM were significantly inhibited by replacement of the medium with a Ca2+ free solution (P less than 0.01). These results imply that opsonized zymosan inhibits cytoplasmic motility of AM via external calcium influx.

4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyraz↗

PubMed1987

Modulation of zymosan stimulated leukotriene release by dietary unsaturated fatty acids.

The quantity of leukotrienes produced in an inflammation model, the stimulated mouse peritoneum, was affected by dietary manipulation of tissue arachidonic acid, the immediate leukotriene (LT) precursor. Fifty ng of LTE4 was synthesized (after injection of zymosan) by the peritoneal cavity of mice maintained on olive oil as a dietary source of unsaturated fatty acids. Animals maintained on corn oil, exhibited significantly enhanced leukotriene biosynthesis upon stimulation by zymosan. Mice fed menhaden oil, a fat source rich in n-3 fatty acids produced 50% less leukotriene E4 than animals fed olive oil. The results indicated that production of leukotrienes, potent mediators of inflammatory reactions, are affected by the type of polyunsaturated fatty acids in the diet.

Animals↗

PubMed1994

Do barbiturates impair zymosan-induced granulocyte function?

PURPOSE: The dose-response relationship of commercially available preparations of methohexital, pentobarbital, phenobarbital, and thiopental and their respective drug-free solutions on granulocyte function was investigated to evaluate whether suppression of neutrophil chemiluminescence is mediated by the barbiturates themselves or by their drug-free solutions. Furthermore, it was assessed whether suppression of chemiluminescence is due to an interaction mainly with neutrophils or to free radical scavenging. METHODS: The dose-response effects of the four barbiturates on granulocyte function were tested by zymosan-induced neutrophil chemiluminescence and, in addition, in a cell-free chemiluminescence system. RESULTS: Methohexital and pentobarbital did not influence zymosan-induced neutrophil chemiluminescence, whereas phenobarbital and thiopental decreased neutrophil chemiluminescence in a dose-dependent fashion. Nonphysiological osmolality (531 mosmol/kg) caused this impaired neutrophil chemiluminescence at the greatest concentration of phenobarbital. Thiopental solely suppressed neutrophil chemiluminescence drug specifically. Because thiopental also reduced chemiluminescence generated in a cell-free system, free radical scavenging might contribute to the impaired neutrophil chemiluminescence observed with thiopental. CONCLUSIONS: With the exception of thiopental, barbiturates do not impair oxygen radical production during phagocytosis of neutrophils.

Cell-Free System↗

PubMed1988

Zymosan but not phorbol myristate acetate induces an oxidative burst in rat bone marrow-derived macrophages.

We found that rat bone marrow-derived macrophages responded to opsonized zymosan by releasing superoxide anion. However, these cells were defective in the response to the potent oxidative burst activator phorbol myristate acetate (PMA). This result was observed whatever the concentration of agonist used and with different concentrations of cells. Since it is strongly suspected that protein kinase C (PKC) is involved in the transductional pathway induced by PMA in numerous cell types, and particularly in phagocytes, we studied PKC and we observed that it was functional in rat bone marrow-derived macrophages, but only present at a low level. Thus, we suggest that our results are consistent with the possibility that zymosan-induced respiratory burst may be independent of PKC and that these cells may not possess the minimal level of PKC required for responding to PMA.

Animals↗

PubMed1999

Inhibitory effects of resveratrol analogs on unopsonized zymosan-induced oxygen radical production.

Resveratrol, a natural hydroxystilbene, has been reported to have anti-inflammatory and anticarcinogenic activities. Inhibitory effects of resveratrol and its analogs on reactive oxygen species (ROS) production in unopsonized zymosan-stimulated murine macrophage Raw264.7 cells, human monocytes, and neutrophils were analyzed to investigate if the anti-inflammatory and anticarcinogenic activities of resveratrol are related to the inhibition of ROS production. Resveratrol was a potent inhibitor of ROS production in both unopsonized zymosan-stimulated Raw264.7 cells and human monocytes and neutrophils. Resveratrol exhibited 50% inhibition values (IC50) of 17 microM in activated Raw264.7 cells, 18 microM in human monocytes, and 23 microM in human neutrophils. 3,5-Dihydroxy-4'-methoxystilbene or 3,4'-dimethoxy-5-hydroxystilbene exhibited IC50 values of 63 or 73 microM in Raw264.7 cells, 51 or >100 microM in human monocytes, and 10 or 37 microM in human neutrophils, respectively. Trimethylresveratrol, piceid, and 3,5-dihydroxy-4'-methoxystilbene-3-O-beta-D-glucoside were weak inhibitors of ROS production. Thus, resveratrol was identified as a potent inhibitor of ROS production, which might be one biochemical mechanism related to its anti-inflammatory and anticarcinogenic activities. The number and position of hydroxy substituents in resveratrol analogs seem to play an important role in the inhibitory potency of ROS production.

Adult↗

PubMed1999

Protective effects of poly (ADP-ribose) synthase inhibitors in zymosan-activated plasma induced paw edema.

The aim of the present study was to investigate the role of poly (ADP-ribose) synthetase (PARS) in a model of acute local inflammation (zymosan-activated plasma (ZAP)-induced paw edema), in which the oxyradicals, nitric oxide and peroxynitrite, are known to play a crucial role. Injection of zymosan-activated plasma (ZAP) into the rat paw induced edema formation. The maximal increase in paw volume was observed at three hours after administration (maximal in paw volume: 1.29+/-0.09 ml). At this time point, there was a marked increase in neutrophil infiltration in the paw, as measured by an increase in myeloperoxidase (MPO) activity in the paw tissue (260+/-25 mU/100 mg wet tissue). However, ZAP-induced paw edema was significantly reduced in a dose-dependent manner by treatment with 3-aminobenzamide (3-AB) or nicotinamide (NIC), two inhibitors of PARS, at 1, 2, 3, 4 hours after ZAP injection. PARS inhibition also caused a significant reduction of MPO activity. The paw tissues were also examined immunohistochemically for the presence of nitrotyrosine (a footprint for peroxynitrite formation). At 3 h following ZAP injection, staining for nitrotyrosine were also found to be localised within discrete cells in the inflamed paw tissue. Treatment with PARS inhibitor prevented the appearance of nitrotyrosine in the tissues. Our results suggest that in paw edema induced by ZAP, inhibition of PARS exert potent anti-inflammatory effects.

Animals↗

PubMedDate not supplied

A comparison of the chemiluminescent response of Crassostrea virginica and Morone saxatilis phagocytes to zymosan and viable Listonella anguillarum.

If reactive oxygen species (ROS) produced by hemocytes of the eastern oyster, Crassostrea virginica, impart bactericidal activity, exposure of hemocytes to bacteria should result in increased ROS generation. In an earlier study, this hypothesis was tested using luminol- and lucigenin-augmented chemiluminescence (CL) to measure ROS production. The bacterium Listonella anguillarum did not stimulate a net increase in hemocyte-derived CL, and it was suggested that bacterial antioxidants might suppress hemocyte CL. In the present study a comparison was made, under identical assay conditions, of the zymosan- and bacteria-enhanced luminol CL produced by eastern oyster hemocytes and by striped bass (Morone saxatilis) macrophages, for which L. anguillarum has been shown to be a stimulus in CL reactions. The response to zymosan produced by bass phagocytes was two orders of magnitude greater than that generated by eastern oyster hemocytes. Whereas an increase in net ROS production was not evident when oyster hemocytes were exposed to L. anguillarum, significant stimulation of striped bass macrophage-derived CL occurred. These data suggest that striped bass macrophages have a greater capacity to generate ROS than oyster hemocytes, enabling them to surpass the antioxidant capability of L. anguillarum and produce a luminol CL response.

Animals↗