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)

The effect of aqueous extract of Salvia plebeia R. Brown (Labiatae) (SPAE) on the mast cell mediated immediate-type allergic reactions in rats was studied. SPAE (0.05 to 1 g/kg) inhibited systemic allergic reaction induced by compound 48/80. SPAE (0.001 and 1 g/kg) dose-dependently inhibited passive cutaneous anaphylaxis (PCA) when intraperitoneally, intraveneously or orally administered. When SPAE was pretreated at the same concentrations with systemic allergic reaction test, the plasma histamine levels were reduced in a dose-dependent manner. SPAE (0.001 to 1 mg/mL) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cyclic AMP in RPMC, when SPAE (0.1 and 1 mg/mL) was added, significantly increased compared with that of basal cells. Moreover, SPAE (0.01 to 1 mg/mL) had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-alpha (TNF-alpha) production. These results indicate that SPAE may possess strong antiallergic activity and suggest that differences in bioavailability may cause differential activity following different administration routes.
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PMID:Inhibition of immediate-type allergic reactions by the aqueous extract of Salvia plebeia. 1206 55

Stress activates the hypothalamic-pituitary-adrenal (HPA) axis through release of corticotropin releasing factor (CRF), leading to production of glucocorticoids that down regulate immune responses. However, acute stress via CRF also has pro-inflammatory effects. We previously showed that acute stress increases rat blood-brain barrier (BBB) permeability, an effect involving brain mast cells and CRF, as it was absent in W/W(v) mast cell-deficient mice and was blocked by the CRF-receptor antagonist, Antalarmin. We investigated if CRF could also have a direct action on brain microvessel endothelial cells (BMEC) isolated from rat and bovine brain. BMEC were cultured and identified by electron microscopy. Western blot analysis of cultured BMEC identified CRF receptor protein; stimulation with CRF, or it structural analogue urocortin (Ucn) showed that the receptor is functionally coupled to adenylate cyclase as it increased cyclic AMP (cAMP) levels by 2-fold. These findings suggest that CRF could affect BMEC structure or function, as reported for increased cAMP levels by other studies. It is, therefore, possible that CRF may directly regulate BBB permeability, in addition to any effect mediated via brain mast cells.
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PMID:Corticotropin-releasing factor (CRF) can directly affect brain microvessel endothelial cells. 1266 88

The effect of aqueous extract of Phlomis umbrosa Turcz. (Labiatae) root (PUAE) on mast cell-dependent immediate-type allergic reaction by anal therapy was investigated. PUAE (0.01 to 1 g/kg) dose-dependently inhibited systemic anaphylaxis induced by compound 48/80 in mice. When PUAE was pretreated at the same concentrations with systemic anaphylaxis, the plasma histamine levels were reduced in a dose-dependent manner. PUAE (0.1 and 1 g/kg) also significantly inhibited local anaphylaxis activated by anti-DNP IgE. PUAE (0.001 to 1 mg/mL) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cyclic AMP (cAMP) in human mast cells (HMC-1 cells) when PUAE (1 mg/mL) was added, transiently and significantly increased compared with that of basal cells. In addition, PUAE (0.1 and 1 mg/mL) inhibited the secretion of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6 in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated HMC-1 cells. These results provide evidence that anal therapy of PUAE may be beneficial in the treatment of allergic diseases.
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PMID:Effect of Phlomis umbrosa root on mast cell-dependent immediate-type allergic reactions by anal therapy. 1267 1

Mast cell histamine release is considered to be associated with the etiology of anaphylactoid reactions to iodinated radiographic contrast media (RCM). In the present study, the effects of various ionic and non-ionic RCM on histamine release from mast cells were compared, and the possible mechanisms of the histamine release were subsequently determined. Both ionic (ioxaglate and amidotrizoate) and non-ionic (iohexol, ioversol, iomeprol, iopamidol and iotrolan) RCM increased histamine release from the dissociated rat pulmonary cells, whereby ionic materials were more potent than non-ionic agents. There was no significant correlation between the extent of histamine release and the osmolarity of each RCM solution. In addition, hyperosmotic mannitol solution (1000 mOsm/kg) caused no marked histamine release. Thus, it is unlikely that the hyperosmolarity of RCM solutions contributes to the histamine release. RCM also stimulated, but to a lesser extent, the histamine release from rat peritoneal cells. The RCM-induced histamine release from both types of cells was inhibited by dibutyl cyclic AMP or combined treatment with forskolin and 3-isobutyl-1-methylxanthine. Corresponding to these results, RCM markedly reduced the cellular cyclic AMP content. On the other hand, the removal of intracellular but not the extracellular Ca2+ attenuated the RCM-induced mast cell histamine release. From these findings, it is suggested that the decrease in cellular cyclic AMP content and an increase in intracellular Ca2+ contribute at least in part to the RCM-induced mast cell histamine release.
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PMID:Roles of intracellular Ca2+ and cyclic AMP in mast cell histamine release induced by radiographic contrast media. 1269 Apr 28

Human mast cells express the intermediate conductance Ca2+-activated K+ channel iKCa1, which opens following IgE-dependent activation. This results in cell membrane hyperpolarization and potentiation of both Ca2+ influx and degranulation. Mast cell activation is attenuated following exposure to beta2-adrenoceptor agonists such as salbutamol, an effect postulated to operate via intracellular cyclic AMP. In this study, we show that salbutamol closes iKCa1 in mast cells derived from human lung and peripheral blood. Salbutamol (1-10 microM) inhibited iKCa1 currents following activation with both anti-IgE and the iKCa1 opener 1-EBIO, and was reversed by removing salbutamol or by the addition of the selective beta2-adrenoceptor antagonist and inverse agonist ICI 118551. Interestingly, ICI 118551 consistently opened iKCa1 in quiescent cells, suggesting that constitutive beta2-receptor signaling suppresses channel activity. Manipulation of intracellular cAMP, Galphai, and Galphas demonstrates that the beta2-adrenergic effects are consistent with a membrane-delimited mechanism involving Galphas. This is the first demonstration that gating of the iKCa1 channel is regulated by a G protein-coupled receptor and provides a clearly defined mechanism for the mast cell "stabilizing" effect of beta2-agonists. Furthermore, the degree of constitutive beta2-receptor "tone" may control the threshold for human mast cell activation through the regulation of iKCa1.
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PMID:Beta2-adrenoceptor regulation of the K+ channel iKCa1 in human mast cells. 1581 38

This review summarizes the principal therapeutic responses to the preferential COX-2 NSAID, nimesulide, in treating musculo-skeletal joint symptoms and various acute and chronic pain conditions and the mode of action in relation to therapy in these states. In extensive studies in laboratory animal models and clinical trails in patients nimesulide has been found to have potent analgesic, anti-inflammatory and anti-pyretic activities. It is approved for use in over 50 countries worldwide (including those in the EU, South and Central America, China, India and some other South-East Asia) for the treatment of acute pain, the symptomatic treatment of painful osteoarthritis and primary dysmenorrhoea. Its mode of action in these states is related to the preferential inhibition of the production of cyclo-oxygenase-2 (COX-2) and other inflammatory mediators whose production is controlled by stimulation of cyclic-3 ,5'-adenosine monophosphate (cAMP); this means that nimesulide is a multi-factorial drug in controlling inflammation and pain. The adverse reaction profile of nimesulide is, in general, like that of other NSAIDs. It does, however, have relatively low occurrence of gastro-intestinal (GI) side effects which is related to its low propensity to inhibit the physiologically important COX-1 in the GI mucosa and important physicochemical properties (high pKa of 6.5 and lipophilicity) as well as inhibiting of mast cell derived histamine and acid secretion in the stomach. In contrast with the coxibs, nimesulide has not been found to have appreciable cardiovascular toxicity.
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PMID:Current status of the therapeutic uses and actions of the preferential cyclo-oxygenase-2 NSAID, nimesulide. 1698 92

Antigen-mediated cross-linking of IgE bound to mast cells via the high affinity receptor for IgE triggers a signaling cascade that results in the release of intracellular calcium stores, followed by an influx of extracellular calcium. The collective increase in intracellular calcium is critical to the release of the granular contents of the mast cell, which include the mediators of acute anaphylaxis. We show that the sensitivity of the mast cell to antigen-mediated degranulation through this pathway can be dramatically influenced by the A2b adenosine receptor. Loss of this Gs-coupled receptor on mouse bone marrow-derived mast cells results in decreased basal levels of cyclic AMP and an excessive influx of extracellular calcium through store-operated calcium channels following antigen activation. Mice lacking the A2b receptor display increased sensitivity to IgE-mediated anaphylaxis. Collectively, these findings show that the A2b adenosine receptor functions as a critical regulator of signaling pathways within the mast cell, which act in concert to limit the magnitude of mast cell responsiveness when antigen is encountered.
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PMID:Enhanced mast cell activation in mice deficient in the A2b adenosine receptor. 1720 Apr 8

Trichinella spiralis infection causes hyperexcitability in enteric after-hyperpolarising (AH) sensory neurons that is mimicked by neural, immune or inflammatory mediators known to stimulate adenylyl cyclase (AC)/cyclic 3',5'-adenosine monophosphate (cAMP) signaling. The hypothesis was tested that ongoing modulation and sustained amplification in the AC/cAMP/phosphorylated cAMP related element binding protrein (pCREB) signaling pathway contributes to hyperexcitability and neuronal plasticity in gut sensory neurons after nematode infection. Electrophysiological, immunological, molecular biological or immunochemical studies were done in T. spiralis-infected guinea-pigs (8000 larvae or saline) after acute-inflammation (7 days) or 35 days p.i., after intestinal clearance. Acute-inflammation caused AH-cell hyperexcitability and elevated mucosal and neural tissue levels of myeloperoxidase, mast cell tryptase, prostaglandin E2, leukotrine B4, lipid peroxidation, nitric oxide and gelatinase; lower level inflammation persisted 35 days p.i. Acute exposure to blockers of AC, histamine, cyclooxygenase or leukotriene pathways suppressed AH-cell hyperexcitability in a reversible manner. Basal cAMP responses or those evoked by forskolin (FSK), Ro-20-1724, histamine or substance P in isolated myenteric ganglia were augmented after T. spiralis infection; up-regulation also occurred in AC expression and AC-immunoreactivity in calbindin (AH) neurons. The cAMP-dependent slow excitatory synaptic transmission-like responses to histamine (mast cell mediator) or substance P (neurotransmitter) acting via G-protein coupled receptors (GPCR) in AH neurons were augmented by up to 2.5-fold after T. spiralis infection. FSK, histamine, substance P or T. spiralis acute infection caused a 5- to 30-fold increase in cAMP-dependent nuclear CREB phosphorylation in isolated ganglia or calbindin (AH) neurons. AC and CREB phosphorylation remained elevated 35 days p.i.. Ongoing immune activation, AC up-regulation, enhanced phosphodiesterase IV activity and facilitation of the GPCR-AC/cAMP/pCREB signaling pathway contributes to T. spiralis-induced neuronal plasticity and AH-cell hyperexcitability. This may be relevant in gut nematode infections and inflammatory bowel diseases, and is a potential therapeutic target.
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PMID:Cyclic AMP signaling contributes to neural plasticity and hyperexcitability in AH sensory neurons following intestinal Trichinella spiralis-induced inflammation. 1730 83

Human lung mast cells (HLMC) express the Ca2+-activated K+ channel KCa3.1, which opens following IgE-dependent activation. This hyperpolarises the cell membrane and potentiates both Ca2+ influx and degranulation. In addition, blockade of KCa3.1 profoundly inhibits HLMC migration to a variety of diverse chemotactic stimuli. KCa3.1 activation is attenuated by the beta2adrenoceptor through a Galphas-coupled mechanism independent of cyclic AMP. Adenosine is an important mediator that both attenuates and enhances HLMC mediator release through the Galphas-coupled A2A and A2B adenosine receptors, respectively. We show that at concentrations that inhibit HLMC degranulation (10(-5)-10(-3) M), adenosine closes KCa3.1 both dose-dependently and reversibly. KCa3.1 suppression by adenosine was reversed partially by the selective adenosine A2A receptor antagonist ZM241385 but not by the A2B receptor antagonist MRS1754, and the effects of adenosine were mimicked by the selective A2A receptor agonist CGS21680. Adenosine also opened a depolarising current carried by non-selective cations. As predicted from the role of KCa3.1 in HLMC migration, adenosine abolished HLMC chemotaxis to asthmatic airway smooth muscle-conditioned medium. In summary, the Galphas-coupled adenosine A2A receptor closes KCa3.1, providing a clearly defined mechanism by which adenosine inhibits HLMC migration and degranulation. A2A receptor agonists with channel-modulating function may be useful for the treatment of mast cell-mediated disease.
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PMID:Adenosine closes the K+ channel KCa3.1 in human lung mast cells and inhibits their migration via the adenosine A2A receptor. 1747 52

Human lung mast cells (HLMC) express the Ca(2+)-activated K(+) channel K(Ca)3.1, which plays a crucial role in their migration to a variety of diverse chemotactic stimuli. K(Ca)3.1 activation is attenuated by the beta(2)-adrenoceptor and the adenosine A(2A) receptor through a G(s)-coupled mechanism independent of cyclic AMP. Prostaglandin E(2) promotes degranulation and migration of mouse bone marrow-derived mast cells through the G(i)-coupled EP(3) prostanoid receptor, and induces LTC(4) and cytokine secretion from human cord blood-derived mast cells. However, PGE(2) binding to the G(s)-coupled EP(2) receptor on HLMC inhibits their degranulation. We show that EP(2) receptor engagement closes K(Ca)3.1 in HLMC. The EP(2) receptor-specific agonist butaprost was more potent than PGE(2) in this respect, and the effects of both agonists were reversed by the EP(2) receptor antagonist AH6809. Butaprost markedly inhibited HLMC migration induced by chemokine-rich airway smooth muscle-conditioned media. Interestingly, PGE(2) alone was chemotactic for HLMC at high concentrations (1 microM), but was a more potent chemoattractant for HLMC following EP(2) receptor blockade. Therefore, the G(s)-coupled EP(2) receptor closes K(Ca)3.1 in HLMC and attenuates both chemokine- and PGE(2)-dependent HLMC migration. EP(2) receptor agonists with K(Ca)3.1 modulating function may be useful for the treatment of mast cell-mediated disease.
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PMID:Engagement of the EP2 prostanoid receptor closes the K+ channel KCa3.1 in human lung mast cells and attenuates their migration. 1879 7


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