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)

Anti-inflammatory therapy is actually devolved to glucocorticoids which prevent the release of arachidonic acid from phospholipids and consequently its subsequent transformation into prostaglandins and leukotrienes. This activity explains in part why steroids are better anti-inflammatory agents than acetylsalicylic acid (ASA)-like drugs which only reduce prostaglandin production. Despite their superior therapeutic actions, there are many side effects associated with corticosteroids. Therefore in recent years, research of non-steroid dual inhibitors of prostaglandin and leukotriene production has been developed. The present paper investigates the pharmacological activity of such a new compound, CBS-1108 (2-acetylthiophene-2-thiazolylhydrazone), in comparison with dexamethasone, cyclooxygenase inhibitors (ASA and indomethacin) and reference dual inhibitors (nordihydroguaiaretic acid (NDGA) and 3-amino-1-(m-trifluoromethylphenyl)-2-pyrazoline (BW-755 C]. The two-pathway inhibitors and ASA-like drugs are similarly effective on paracentesis-induced disruption of the blood-aqueous barrier and on croton oil-induced ear edema. On the contrary in an animal model of leukocyte migration and on mast cell degranulation, NDGA and CBS-1108 are very active when the other tested compounds are inefficient.
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PMID:Anti-inflammatory activity of a dual inhibitor of cyclooxygenase and lipoxygenase pathways, CBS-1108 (2-acetylthiophene-2-thiazolylhydrazone). 393 21

Purified human lung mast cells released histamine, leukotrienes, prostaglandin (PG) D2, thromboxane B2 (TxB2), and PGF2 alpha in response to anti-IgE stimulation. Incubation of the cells for 24 h with 10(-6) M dexamethasone, a treatment that inhibits mediator release from human basophils, had no effect on the release of these mediators from mast cells. Dexamethasone treatment of human lung fragments led to little or no inhibition of anti-IgE-induced release of the mast cell-derived mediator, histamine, but produced a significant inhibition of the release of PGE2, PGF2 alpha, and 6-keto-PGF1 alpha. As was the case with purified mast cells, the steroid did not inhibit the release of PGD2 or TxB2 from human lung fragments. Comparison of the quantities of PGD2 and TxB2 produced by purified cells and human lung fragments reveals that the mast cells produce quantities of these metabolites sufficient to account for the entire amount produced by challenged lung fragments. Dexamethasone inhibited spontaneous release from lung fragments of all cyclooxygenase products measured. These results suggest that the human lung parenchymal mast cell phospholipase is not inhibited by dexamethasone, whereas other phospholipase(s) in the lung are inhibited by the steroid. These results may be useful in explaining the resistance of acute allergic reactions, including anaphylaxis, to steroids, despite the potent antiinflammatory activity of steroids on subacute and chronic inflammation, such as in bronchial asthma, which may be initiated by IgE-dependent mechanisms.
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PMID:Effects of dexamethasone on mediator release from human lung fragments and purified human lung mast cells. 613 55

The immediate-type, IgE-mediated rhesus monkey model of asthma due to aerosol challenge with ascaris has been developed to the status of an analytic system for agents capable of inhibiting the antigen-induced airway response. Two antigen-challenge systems have been developed. The standard ascaris challenge uses a dose of antigen that will induce an airway response in all reactive animals. In the threshold antigen-challenge system, the threshold dose of antigen that will induce an airway response is determined and is relatively constant for the individual animal. Both of these types of response were inhibited by 5,8,11,14-eicosatetraynoic acid (ETYA). This action may be through the inhibition of the lipoxygenase and cyclooxygenase metabolic pathways of arachidonic acid and possibly through inhibition of production of slow-reacting substance. ETYA also inhibits cutaneous immediate-type reactivity to ascaris antigen in a dose-response relationship. This may be the result of inhibition of mast cell histamine release or the inhibition of production of other vasoactive mediators. An alternative explanation for the action of ETYA in the airway and skin responses is that ETYA may act as an end-organ antagonist to released bioactive mediators. ETYA is the first agent, other than beta agonists or cromolyn, that we have been able to demonstrate as clearly having an inhibitory action on the rhesus monkey model of asthma.
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PMID:Inhibition of immunoglobulin E-mediated, antigen-induced monkey asthma and skin reactions by 5, 8, 11, 14-eicosatetraynoic acid. 616 Nov 46

Recent studies indicate that both arachidonic acid (AA) metabolism and phospholipid (PL) metabolism are markedly stimulated during the release of mediators from mast cells. The relationship between stimulated AA metabolism and stimulated PL metabolism in isolated rat mast cells was investigated and then correlated with the secretory process. ETYA (5,8,11,14-eicosatetraynoic acid, a known inhibitor of cyclooxygenase and lipoxygenase pathways of AA metabolism) inhibited 32PO4 incorporation into phosphatidic acid (PA), phosphatidylinositol (PI), and phoshodidylcholine (PC) in both unstimulated mast cells and mast cells stimulated by cross-linking of surface IgE molecules. ID50 values for inhibition of mediator release and of basal and stimulated 32PO4 incorporation into PL were 50 to 60 microM ETYA. Indomethacin (1 to 10 microM) and aspirin (10 to 100 microM) had no significant effect on 32PO4 incorporation or on mediator release. AA (10 microM) inhibited PL labeling in resting mast cells and rendered the cells less responsive to secretory signals. Preincubation of the cells with indomethacin (1 microM) blocked both of these AA effects. When AA was added to stimulated mast cells, however, both PL labeling and mediator release were enhanced. Thus, each of the alterations in AA metabolism caused parallel changes in mast cell PL metabolism and in mediator release. Since both basal and stimulated PL metabolism were modified by ETYA and AA, some form of direct regulation of mast cell PL metabolism by AA metabolites seems likely. The close parallelism of effects on mediator release and on PL metabolism suggests that modulation of mast cell function by AA metabolites may be mediated at lest in part by effects on lipid metabolism.
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PMID:Lipid metabolism during mediator release from mast cells: studies of the role of arachidonic acid metabolism in the control of phospholipid metabolism. 616 27

Antigen challenge of passively sensitized chopped human lung resulted in the generation of several arachidonic acid cyclooxygenase metabolites (AACM): thromboxane A2 (TxA2) as measured by its stable metabolite TxB2, prostaglandin D2 (PgD2), prostacyclin (PgI2) as measured by its stable metabolite 6-keto-PgF1 alpha, prostaglandin F2 alpha (PgF2 alpha), and prostaglandin E (PgE). The kinetics of AACM release after antigen challenge paralleled histamine release. All AACM were released in an antigen dose-dependent manner and reached maximal release at antigen concentrations lower than those required for maximal histamine release. Quantitatively, of the AACM measured, PgD2 and PgI2 were found to predominate in anaphylactic reactions of human lung parenchyma. Generation of PgD2 and PgI2 were 3- to 7-fold greater than that of other AACM measured. Thromboxane B2 was generated in quantities comparable to PgE and PgF2 alpha. Studies were designed to test the hypothesis that lung smooth muscle contraction per se can account for the generated AACM that are released during anaphylaxis of the lung. The studies compared antigen-induced AACM generation with methacholine-induced (10(-4) M) AACM generation. The failure to confirm this hypothesis was especially evident for PgD2 where release was dependent on mast cell activation. Thromboxane A2, PgD2, and PgI2 have been reported to have potent effects on smooth muscle. Our data suggested that these AACM are generated in such sufficient quantities that they may function in important aspects of the modulation of hypersensitivity responses in human lungs.
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PMID:Anaphylactic release of thromboxane A2, prostaglandin D2, and prostacyclin from human lung parenchyma. 617 Feb 42

Purified mature rat peritoneal mast cells, on exposure to zymosan or latex beads, phagocytize these particles, although less efficiently than macrophages. During phagocytosis, histamine, beta-glucuronidase, and eosinophil chemotactic factor are released from mast cells in a time-, temperature- and dose-dependent fashion. Complement components, cytochalasin B (5 microgram/ml), and indomethacin (10-6M), enhanced mediator release, whereas compound BW 755C (20 microgram/ml), a cyclooxygenase and lipoxygenase inhibitor of arachidonate metabolism, totally abolished this process. Phagocytosis of mast cell thus activates intracellular mechanisms that closely resemble those observed with other phagocytic cells. These observations add a new perspective to the role of mast cells in inflammatory events.
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PMID:Release of mediators from purified rat mast cells during phagocytosis. 618 56

Enzymatically dispersed human lung parenchymal cells were fractionated according to size by countercurrent centrifugation elutriation. Human lung mast cells eluted throughout the procedure indicating heterogeneity of mast cell diameters. In seven individual lung elutriations, the mean histamine content ranged from 2.5 +/- 0.5 pg/mast cell for the smallest diameter mast cells (8-10 microns) to 10 +/- 2.5 pg/mast cell for the largest (16-20 microns). Intermediate sized mast cells had correspondingly intermediate histamine contents. The maximum release of histamine after anti-IgE stimulation varied with mast cell size. Small mast cells consistently released less histamine (10 +/- 3.6% net) than the largest diameter mast cells (38 +/- 6% net). This differential histamine release could not be explained by cell surface IgE content which was similar in mast cells of all sizes. The concentration of anti-IgE for maximum histamine release was the same (2 micrograms/ml) for mast cells of all sizes. The generation of PGD2, the predominant cyclooxygenase metabolite of the human lung mast cell, also was correlated positively with mast cell size and to the quantity of histamine released. Studies to date indicate no clear pattern in agonist receptor activities as judged by the inhibition of histamine release by PgE2, the beta-adrenergic agonist, fenoterol, and adenosine. We conclude that human lung mast cells are heterogeneous with regard to size and function.
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PMID:Heterogeneity of human mast cells. 619 21

Arachidonic acid metabolism has been explored in preparations of purified human lung mast cells prelabeled with arachidonic acid (AA). Cells were of 83 to greater than 96% purity, and each experiment was performed with four to six different preparations of mast cells. After overnight culture of the purified cells in the presence of 3H-AA, followed by extensive washing in buffer, mast cell uptake of labeled AA was 61.4 +/- 14.8 pmol/10(6) cells with 21 +/- 2.4% of the label in phospholipids, 73 +/- 2.1% in neutral lipids, and 3.6 +/- 0.8% as free AA. Analysis of the distribution of radioactivity in phospholipid classes revealed 51.4 +/- 5.5% of the label in phosphatidylcholine, 14.5 +/- 1.6% in phosphatidylinositol, 12.0 +/- 3.0% in phosphatidylethanolamine, and 9.1 +/- 2.4% in sphingomyelin, with the rest in other phospholipid classes. Challenge of these cells with an optimal concentration of anti-IgE led to the release of 20 +/- 4.0% of cellular histamine and to a reduction in labeled phosphatidylcholine and phosphatidylinositol to 75.5 +/- 8.8% and 84.2 +/- 4.5% of the control levels, respectively, (p less than 0.05); anti-IgE challenge produced no statistically significant change in the quantities of other labeled phospholipids. Activation of human lung mast cells with anti-IgE led to the release of 3.4 +/- 1.3% of the cellular 3H as AA and AA metabolites (1.5 +/- 0.6% as unmetabolized AA) in conjunction with 16 +/- 4.3% of the cellular histamine. Although activation of human lung mast cells with ionophore A23187 caused 70 +/- 1.1% histamine release, a similar quantity of AA and AA metabolites was released (a total of 4.0 +/- 0.8% with 2.3 +/- 1.5% as unmetabolized AA). Analysis of the released metabolites by liquid scintillation spectrometry after high performance liquid chromatography separation showed that approximately equal amounts of metabolites were produced after mast cell activation with anti-IgE and ionophore A23187. In this series of experiments approximately equal amounts of cyclooxygenase and lipoxygenase products were generated.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Arachidonic acid metabolism in purified human lung mast cells. 619 20

The effect of arachidonic acid (AA) metabolism on histamine release and SRS (leukotrienes) production has been studied in guinea-pig lung using anaphylactic reaction and Ca2+ ionophore as the triggering agents in vitro. AA and L-cysteine enhanced SRS production without any appreciable effect on histamine release. Two nonsteroid anti-inflammatory agents, indomethacin and ketoprofen, which block prostaglandin production by the cyclooxygenase pathway, stimulated SRS production but had hardly any effect on histamine release, indicating that SRS synthesis is more sensitive to prostaglandin regulation. Enhancement of SRS production was more pronounced for antigen than for Ca2+ ionophore. This might be related to different cellular origin of SRS with the two triggering agents. Using rat peritoneal cells, both mast cells and the other cells were found to produce SRS in response to Ca2+ ionophore, the amount formed by the latter type of cells being higher. Inhibition of lipoxygenase by 5,8,11,14-eicosatetraynoic acid and nordihydroguaiaretic acid depressed SRS production, but had no effect on histamine release. SRS production triggered by Ca2+ ionophore was more sensitive, possibly because of different cellular origin of SRS in response to the two stimuli. The explanation for the discrepancy between the effect on SRS production and histamine release may also have to be sought in their different origins. SRS may mainly stem from cells, which are more sensitive to the inhibitors than the mast cell, which is the source of histamine.
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PMID:Effect of arachidonic acid metabolism on the release of histamine and SRS (leukotrienes) from guinea-pig lung. 620 64

Dapsone (diaminodiphenylsulfone) has been used therapeutically for a variety of disorders in which mast cell participation has been demonstrated, including bullous pemphigoid and some form of necrotizing vasculitis. The mechanism of action of dapsone in these disorders is unknown but potentially relates to inhibition of mast cell activation and prevention of generation and/or release of mast cell mediators. Evidence for this possibility has been obtained in rat mast cells in which dapsone in a concentration-dependent manner prevented generation of prostaglandin D2 PGD2 from exogenous or endogenous arachidonic acid with 50% inhibition achieved at 1 and 0.2 to 0.4 mM, respectively. Dapsone inhibited cyclooxygenase conversion of arachidonic acid to PGD2 but not the GSH-dependent conversion of 14C-PGH2 to PGD2 by PGH-D isomerase in broken cell preparations. Dapsone prevented the immunologic generation of PGD2 from antigen-challenged rat mast cells but did not affect the release of histamine. Thus dapsone may exert some of its therapeutic effects by prevention of mast cell PGD2 generation.
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PMID:Inhibition of rat mast cell arachidonic acid cyclooxygenase by dapsone. 641 66


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