Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have studied an aspect of the functional heterogeneity of human mast cells, namely responsiveness to the inhibitory effects of sodium cromoglycate and nedocromil sodium. The effects of these drugs were examined on the release of histamine and PGD2 from mast cells of human skin, lung, tonsils, adenoids and intestine. A high concentration, 1000 microM, of sodium cromoglycate was required to significantly inhibit histamine release from lung and tonsillar mast cells. Nedocromil sodium, 1000 microM, was more effective than sodium cromoglycate against histamine release from lung, tonsillar and adenoidal cells. Both compounds showed tachyphylaxis in lung and tonsillar mast cells but not in adenoidal and intestinal mast cells. In contrast, in intestinal mast cells, the effect of nedocromil sodium was weaker and more variable than sodium cromoglycate. Skin mast cells differed from mast cells of the other anatomical sites in being unresponsive to sodium cromoglycate and nedocromil sodium. Our results confirm that high concentrations of sodium cromoglycate and nedocromil sodium are required to achieve even modest inhibition of mediator release from human mast cells under in vitro conditions. Notwithstanding this, the results also indicate that differences exist among skin, lung, tonsillar, adenoidal and intestinal mast cells with respect to their sensitivity to sodium cromoglycate and nedocromil sodium, thus extending our knowledge of functional heterogeneity within the human mast cell populations.
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PMID:Inhibition profiles of sodium cromoglycate and nedocromil sodium on mediator release from mast cells of human skin, lung, tonsil, adenoid and intestine. 137 28

As described in the preceding companion paper, bronchoalveolar lavage (BAL) of the primate Macaca arctoides infected with the nematode Ascaris suum yields a population of cells containing a high proportion of mast cells (21%). Nedocromil sodium, a new drug undergoing clinical evaluation for the treatment of reversible obstructive airways disease, inhibited the release of histamine, LTC4, and PGD2 from these cells challenged with antigen (with IC30 values of 2.1 X 10(-6) M, 2.3 X 10(-6) M, and 1.9 X 10(-6) M, respectively) and with anti-human IgE (IC30 values of 4.7 X 10(-6) M, 1.3 X 10(-6) M, and 1.3 X 10(-6) M, respectively). Cromolyn sodium was essentially inactive. Histamine release from rat peritoneal mast cells induced by anti-rat IgE was, however, inhibited by both nedocromil sodium and cromolyn sodium with IC30 values of 1.1 X 10(-6) M and 5.5 X 10(-7) M, respectively. Both compounds induce phosphorylation of a 78,000 m.w. protein in the rat peritoneal mast cell in the absence of any stimulus at the same concentrations as those required to inhibit histamine release stimulated by anti-IgE. This event may be part of a feedback mechanism to limit degranulation. Nedocromil sodium and cromolyn sodium were equipotent in their ability to inhibit anti-IgE-induced histamine release from rat peritoneal mast cells, but differed markedly in their ability to inhibit histamine release from macaque BAL cells.
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PMID:Characterization of primate bronchoalveolar mast cells. II. Inhibition of histamine, LTC4, and PGD2 release from primate bronchoalveolar mast cells and a comparison with rat peritoneal mast cells. 243 Oct 49

We have developed a model of asthma in conscious guinea-pigs in which inhalation challenge with specific allergen induces both early and late phase reductions in specific airways conductance. Analysis of cells removed from the airways by bronchoalveolar lavage showed the presence of a neutrophilia, which reached a maximum at 17 hours, and an eosinophilia which developed more slowly, still increasing at 72 hours. Nedocromil sodium inhaled before challenge inhibited both the early and late phase responses. In contrast, the beta-adrenoceptor stimulant, salbutamol, inhibited only the early phase. When inhaled 6 hours after challenge, i.e. between the early and late phase responses, the late phase bronchoconstriction was prevented by nedocromil sodium but only partially by salbutamol. Evidence that the neutrophilia was not functionally associated with the late response was gained from the observations that it was inhibited by both nedocromil sodium and salbutamol, whereas only nedocromil sodium blocked the late phase airways response. When administered 6 hours after challenge, nedocromil sodium reduced eosinophil accumulation at 72 hours in parallel with inhibiting a secondary late response at this time. These results demonstrate that nedocromil sodium is able to prevent both early and late phase reductions in airways function in an animal model of allergic asthma. Whereas inhibition of the early response may reflect an effect on mast cell mediator release, the effects of nedocromil sodium on the late response and on eosinophil accumulation are strongly suggestive of an anti-inflammatory effect within the lung.
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PMID:Effect of nedocromil sodium on early and late phase responses to allergen challenge in the guinea-pig. 254 59

The demonstration of a specific receptor for IgE on non-mast cell or basophil leucocytes, such as mononuclear phagocytes, eosinophils and platelets, suggests that these cells may participate directly in immunological disorders of allergy. In this study, inhibition by nedocromil sodium of IgE-dependent activation of human alveolar macrophages, blood monocytes and platelets was investigated. Nedocromil sodium produced an inhibition of IgE-mediated generation of cytotoxic molecules from monocytes and platelets together with a concomitant inhibition of their oxidative metabolism, measured by chemiluminescence. In addition, nedocromil sodium reduced the ability of alveolar macrophages to synthesise and release mediators, estimated by beta-glucuronidase activity. Furthermore, nedocromil sodium inhibited the abnormal response to aspirin of platelets from aspirin-sensitive asthmatics at therapeutic concentrations. These studies confirm that nedocromil sodium acts on a cell compartment other than the classical mast cell population in IgE-dependent allergy and asthma.
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PMID:Nedocromil sodium inhibition of IgE-mediated activation of human mononuclear phagocytes and platelets from asthmatics. 254 66

Nedocromil sodium and cromolyn (sodium cromoglycate) are prophylactic agents in asthma which were initially found to be inhibitors of mast cell activation. Recent evidence has suggested that their effects on granulocyte-mediated reactions may contribute to their therapeutic effects. Recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF) enhance the activity of granulocytes in antibody-dependent cell-mediated cytotoxicity (ADCC). Preincubation of purified neutrophils or eosinophils with nedocromil sodium or cromolyn partially inhibited their ability to mediate ADCC when stimulated by GM-CSF or TNF. Preincubation with nedocromil sodium did not alter the ability of neutrophils to produce superoxide or release lysozyme in response to soluble or phagocytic stimuli, and GM-CSF-enhanced superoxide production triggered by chemotactic peptide was not altered in such drug-treated neutrophils. After nedocromil sodium treatment, neutrophils showed no consistent changes in TNF-stimulated adherence to either plastic culture wells or umbilical vein endothelium. These findings demonstrate that nedocromil sodium and cromolyn directly and selectively affect the function of granulocytes in vitro. While drug-treated granulocytes were impaired in immune-directed cytotoxicity stimulated by GM-CSF or TNF, activation of other granulocyte functions by the same stimuli was intact.
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PMID:Nedocromil sodium and cromolyn (sodium cromoglycate) selectively inhibit antibody-dependent granulocyte-mediated cytotoxicity. 284 86

Antigen challenge of ovalbumin (OA)-sensitized guinea pigs results in significant (p less than 0.05) increases in vascular permeability to Evans blue (EB) dye in the airways, esophagus, and bladder. Mean values +/- SEM in ng EB/mg wet weight tissue for unsensitized versus sensitized animals were: trachea, 23.6 +/- 6.6 versus 92.5 +/- 11.1; main bronchi, 31.1 +/- 12.2 versus 153.1 +/- 14.9; "central" intrapulmonary airways (ipa), 34.6 +/- 11.2 versus 101.3 +/- 6.2; and "peripheral" ipa, 26.2 +/- 6.8 versus 93.5 +/- 13.6. We investigated the involvement of several mediators of inflammation in this process. FPL 55712, a sulfidopeptide leukotriene receptor antagonist, caused significant inhibition of leakage in trachea (to 55.1 +/- 9.8) and main bronchi (91.7 +/- 15.8). Blockade of the cyclooxygenase and lipoxygenase pathways with BW 755C, but not of the cyclooxygenase pathway alone with indomethacin, also significantly reduced EB dye extravasation in trachea (55.1 +/- 18.0), main bronchi (71.7 +/- 23.0), and "central" ipa (62.7 +/- 16.4). The histamine antagonists, chlorpheniramine and cimetidine, only inhibited microvascular leakage in main bronchi (94.4 +/- 20.0). PAF-receptor blockade with the ginkgolide mixture BN 52063 had no effect. Nedocromil sodium, a mast cell stabilizer and an inhibitor of inflammatory cell activation, caused significant inhibition throughout the airways: trachea, 50.4 +/- 10.6; main bronchi, 72.0 +/- 15.3; "central" ipa 61.0 +/- 8.6; "peripheral" ipa 41.9 +/- 12.2. Thus, histamine and lipoxygenase products (in particular, leukotrienes), but not PAF, may mediate the antigen-induced increase in vascular permeability to different degrees in differing regions of the respiratory tract in guinea pigs.
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PMID:Inflammatory mediators involved in antigen-induced airway microvascular leakage in guinea pigs. 284 29

Nedocromil sodium is commonly suggested to reduce allergic inflammation by inhibiting mediator release from mast cells. However, nedocromil also exhibits a wide range of additional anti-inflammatory activities, including inhibition of increased vascular permeability induced by individual mediators such as histamine. In the present study, we have further characterized the mode of action of nedocromil in a rat model for hind paw edema. Mast cell-dependent edema was induced with compound 48/80 (edema response mainly due to 5-hydroxytryptamine release), and direct mediator-induced plasma extravasation was evoked by exogenous 5-hydroxytryptamine (both agents injected locally). Local pretreatment with nedocromil for 20 min dose-dependently inhibited the edema evoked by compound 48/80 more effectively than that induced by 5-hydroxytryptamine. However, after 2 h pretreatment, both the 5-hydroxytryptamine-and compound 48/80-induced edema responses were inhibited to approximately the same extent by a range of concentrations of nedocromil, as well as by dexamethasone. Local inhibition of RNA/protein synthesis with actinomycin-D abolished the effects of both dexamethasone and nedocromil (2 h local pretreatment). We thus conclude that nedocromil can produce an 'anti-exudative' effect that is independent of inhibition of mast cell mediator release, is slow in onset, and requires de novo protein synthesis.
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PMID:Delayed anti-inflammatory action of nedocromil sodium in the rat paw is dependent on de novo protein synthesis. 749 78

Bronchial asthma is a complex inflammatory disorder that involves activation of, and mediator release by, a variety of cells including mast cells. Nedocromil sodium can inhibit the activity of a range of inflammatory cells including mast cells, as has been demonstrated in several studies. In human beings nedocromil sodium inhibited histamine secretion from mast cells obtained by bronchoalveolar lavage and from dispersed lung mast cells. Tachyphylaxis was noted with the latter cells only. Because the bronchoalveolar lavage mast cells would come into direct contact with inhaled drugs, these cells may be a major target for the action of nedocromil sodium. The inhibitory effects of nedocromil sodium on mast cell activation and secretion are one way the drug may be effective in controlling airway obstruction.
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PMID:Effect of nedocromil sodium on mediator release from mast cells. 768 9

The vital role of inflammation in the induction and perpetuation of asthmatic responses is now a widely accepted concept. Effective management of asthma requires modulation of asthmatic inflammatory responses. Eosinophils play a critical role in producing inflammation within the asthmatic lungs. Serologic assessment of the level of eosinophilic cationic protein (ECP) may be useful in assessing the degree of activation of eosinophils in asthma and the effect of pharmacotherapy on activated eosinophils. Several clinical trials have noted that ECP levels fluctuate in direct relationship to the amount of ongoing bronchospasm and asthmatic inflammation. Modulation of inflammation in asthma can occur through pharmacologic means. Nedocromil sodium has been demonstrated to significantly affect both early-phase and late-phase inflammatory events including effects on mast cell activation and effects on eosinophil function. Nedocromil sodium has also been noted to affect production and activity of cytokines that are vital to the perpetuation of the asthmatic late-phase response. Unlike cromolyn sodium, nedocromil sodium inhibits late-phase inflammation even when administered after the early phase of the allergic response and has also been demonstrated to be a steroid-sparing agent in mild-to-moderate asthmatics who require inhaled beclomethasone. Modulation of the metabolism of arachidonic acid, thereby affecting levels of prostaglandins and leukotrienes, may be extremely useful in selective asthmatic patients. Those patients having aspirin sensitivity and chronic rhinitis associated with asthma seem to be particularly responsive to arachidonic acid metabolites. In such patients, use of aspirin desensitization may be considered. Newer anti-inflammatory agents being investigated as treatments for asthma include methotrexate, hydroxychloroquin, auronifin, and sulfonylureas, among others.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Mediator assays and modulation of inflammation in asthma: introduction. 779 58

Nedocromil sodium, a pyranoquinolone, was specifically designed as an agent to suppress allergic inflammation. Nedocromil sodium significantly affects not only the early-phase of allergen-induced responses, but also expression of late-phase inflammation, even when administered after the onset of early-phase responses. Nedocromil sodium also limits bronchoconstriction induced by nonallergic factors, including cold air and sulfur dioxide at dosages lower than required with cromolyn sodium. Nedocromil sodium is more potent than cromolyn sodium in preventing mast cell degranulation in selective animal models. In addition, nedocromil sodium limits leukotriene C4 production by calcium ionophore-stimulated eosinophils and also limits the activity of platelet activating factor to induce neutrophil generation of superoxides. Diurnal variation of peak flow rates in asthmatics and requirement for both beta 2-agonists and inhaled beclomethasone have been noted to be reduced in several trials employing nedocromil sodium, suggesting that its in vivo activity parallels its in vitro activity as an anti-inflammatory agent.
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PMID:Immunopharmacologic profile of nedocromil sodium. 779 61


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