The regulatory effect of SC-236 (4-[5-(4-chlorophenyl)-3-(trifluoromethyl)-1-pyrazol-1-l]benzenesulfonamide) on stem cell factor induced migration of mast cells

SC-236, (4-[5-(4-chlorophenyl)-3-(trifluoromethyl)-1-pyrazol-1-]benzenesulfonamide; C(16)H(11)ClF(3)N(3)O(2)S), is a highly selective cyclooxygenase (COX)-2 inhibitor. Recently, there have been reports that SC-236 protects against cartilage damage in addition to reducing inflammation and pain in osteoarthritis. However, the mechanism involved in the inflammatory allergic reaction has not been examined. Mast cells accumulation can be related to inflammatory conditions, including allergic rhinitis, asthma, and rheumatoid arthritis. The aim of the present study is to investigate the effects of SC-236 on stem cell factor (SCF)-induced migration, morphological alteration, and cytokine production of rat peritoneal mast cells (RPMCs). We observed that SCF significantly induced the migration and morphological alteration. The ability of SCF to enhance migration and morphological alteration was abolished by treatment with SC-236. In addition, production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and vascular endothelial growth factor (VEGF) production induced by SCF was significantly inhibited by treatment with SC-236. Previous work has demonstrated that SCF-induced migration and cytokine production of mast cells require p38 MAPK activation. We also showed that SC-236 suppresses the SCF-induced p38 MAPK activation in RPMCs. These data suggest that SC-236 inhibits migration and cytokine production through suppression of p38 MAPK activation. These results provided new insight into the pharmacological actions of SC-236 and its potential therapeutic role in the treatment of inflammatory allergic diseases.     

Inhibition of immunologic and nonimmunologic stimulation-mediated anaphylactic reactions by water extract of white eggplant (Solanum melongena).

We investigated the effect of water extract of Solanum melongena(SMWE) on immunologic and nonimmunologic stimulation-mediated anaphylactic reactions. Nonimmunologic anaphylactic reaction was induced by compound 48/80 injection. Oral administration of SMWE (1 g kg(-1)) completely inhibited compound 48/80-induced anaphylactic reaction. Immunologic anaphylactic reaction was generated by sensitizing the skin with anti-dinitrophenyl (DNP) IgE followed 48 h later with an injection of antigen. Oral administration of SMWE (0.01--1 g kg(-1)) significantly inhibited passive cutaneous anaphylactic reaction activated by anti-DNP IgE to between 83.10 +/- 1.67% and 70.17 +/- 2.17%. SMWE (0.01--1 mg ml(-1)) also inhibited histamine release activated by compound 48/80 to between 93 +/- 2.65 and 70 +/- 1.50%. Moreover, SMWE (0.01--1 mg ml(-1)) had a significant inhibitory effect on IgE-induced tumor necrosis factor (TNF)-alpha secretion from rat peritoneal mast cells. These results indicate that SMWE inhibits immunologic and nonimmunologic stimulation-mediated anaphylactic reactions and TNF-alpha secretion from mast cells.     

Βeta-eudesmol reduces stem cell factor-induced mast cell migration

Previously, we showed the inhibitory effects of β-eudesmol on mast cell-mediated allergic inflammatory responses. Stem cell factor (SCF) participates in allergic reactions through the differentiation and migration of mast cells. However, the effects of β-eudesmol on SCF-mediated allergic reactions are poorly understood. Herein, we showed that a treatment of rat peritoneal mast cells (RPMCs) with β-eudesmol markedly suppressed SCF-induced mast cell migration and morphological alterations in a concentration-dependent manner. β-eudesmol also reduced F-actin formation. The activation of Fyn kinase, Rac1 GTPase, and p38 mitogen-activated protein kinases as increased by SCF was reduced by β-eudesmol. Moreover, β-eudesmol significantly abolished SCF-induced tumor necrosis factor-α and intercellular adhesion molecule-1 production without cytotoxicity. These results demonstrate that β-eudesmol has an anti-allergic inflammatory effect through the inhibition of mast cell migration and inflammatory cytokine production.     

Salviae radix root extract inhibits immunoglobulin E-mediated allergic reaction.

We investigated the effects of the aqueous extract of Salviae radix root (SRRAE) on immediate allergic reactions. SRRAE inhibited by 72.7% passive cutaneous anaphylaxis activated by anti-dinitrophenyl (DNP) immunoglobulin E (IgE). SRRAE dose dependently inhibited histamine release and tumor necrosis factor-alpha production from the rat peritoneal mast cells (RPMCs) by anti-DNP IgE. However, SRRAE showed no significant inhibitory effect on compound 48/80-induced systemic allergic reaction and histamine release from RPMCs. The level of cAMP in RPMCs, when SRRAE was added, significantly increased compared with that of a normal control. These results indicate that SRRAE may contain compounds with actions that inhibit anti-DNP IgE-induced mast cell degranulation in rats.     

Mechanism of action of disodium cromoglycate--mast cell calcium ion influx after a histamine-releasing stimulus.

Rat peritoneal mast cells release histamine and accumulate ⁴⁵Ca in a dose-dependent manner when concentrations of compound 48/80 ranging from 0·1 to 1·0 μg/ml are incubated with suspensions of the cells for 5 min at 37°. Influx of ⁴⁵Ca stimulated by compound 48/80 can be inhibited to varying degrees by prior addition of disodium cromoglycate. Inhibition was dependent on the concentration of both disodium cromoglycate and compound 48/80. The electrokinetic properties of intact rat mast cells are described; disodium cromoglycate caused a plasma membrane alteration possibly related to Ca²⁺ influx. Cromoglycate increased mast cell electrophoretic mobility but decreased the electrophoretic mobility of rat erythrocytes. The net electrophoretic mobility was a function of terminal sialic acid residues, ionic strenght, and pH. Binding of disodium cromoglycate to Ca²⁺ could not be demonstrated by a variety of sensitive physical techniques. The data support the theory that secretion of mast cell histamine is coupled to Ca²⁺ influx. It is suggested that disodium cromoglycate prevents mast cell histamine release by a plasma membrane alteration which prevents an increase in membrane permeability to Ca²⁺ stimulated by compound 48/80.     

Effects of methyl p-hydroxybenzoate (methyl paraben) on Ca2+ concentration and histamine release in rat peritoneal mast cells

1 Mechanisms of methyl p-hydroxybenzoate (methyl paraben) action in allergic reactions were investigated by measuring the intracellular Ca(2+) concentration ([Ca(2+)](i)) and histamine release in rat peritoneal mast cells (RPMCs). 2 In the presence or absence of extracellular Ca(2+), methyl paraben (0.1-10 mM) increased [Ca(2+)](i), in a concentration-dependent manner. Under both the conditions, methyl paraben alone did not evoke histamine release. 3 In RPMCs pretreated with a protein kinase C (PKC) activator (phorbol 12-myristate 13-acetate (PMA) 3 and 10 nM), methyl paraben (0.3-3 mM) induced histamine release. However, a high concentration (10 mM) of the agent did not increase the histamine release. 4 U73122 (0.1 and 0.5 micro M), an inhibitor of phospholipase C (PLC), significantly inhibited the methyl paraben-induced histamine release in PMA-pretreated RPMCs. U73343 (0.5 micro M), an inactive analogue of U73122, did not inhibit the histamine release caused by methyl paraben. 5 In Ca(2+)-free solution, PLC inhibitors (U73122 0.1 and 0.5 micro M, D609 1-10 micro M) inhibited the methyl paraben-induced increase in [Ca(2+)](i), whereas U73343 (0.5 micro M) did not. 6 Xestospongin C (2-20 micro M) and 2 aminoethoxydiphenyl borate (30 and 100 micro M), blockers of the inositol 1,4,5-trisphosphate (IP(3)) receptor, inhibited the methyl paraben-induced increase in [Ca(2+)](i) in Ca(2+)-free solution. 7 In conclusion, methyl paraben causes an increase in [Ca(2+)](i), which may be due to release of Ca(2+) from storage sites by IP(3) via activation of PLC in RPMCs. In addition, methyl paraben possibly has some inhibitory effects on histamine release via unknown mechanisms.     

IL-37 is protective in allergic contact dermatitis through mast cell inhibition

Allergic contact dermatitis (ACD), characterized predominantly by erythema, vesiculation, and pruritus, is a T cell-mediated skin inflammatory condition. Among immune cells involved in ACD, mast cells (MCs) play an essential role in its pathogenesis. As an inhibitor of proinflammatory IL-1 family members, interleukin 37 (IL-37) has been shown to ameliorate inflammatory responses in various allergic diseases. In this study, we assessed the immunomodulatory effect of IL-37 on allergic inflammation using a 2,4-dinitrofluorobenzene (DNFB)-induced ACD rat model and isolated rat peritoneal mast cells (RPMCs). Systematic application of IL-37 significantly relieved ear swelling, reduced inflammatory cell infiltration, decreased inflammatory cytokine production (TNF-α, IL-1β, IFN-γ, and IL-13), inhibited MC recruitment, lowered IgE levels, and reduced IL-33 production in the local ear tissues with DNFB challenge. Additionally, RPMCs isolated from ACD rats with IL-37 intervention showed downregulation of IL-6, TNF-α, IL-13, and MCP-1 production following IL-33 stimulation, and reduction of β-hexosaminidase and histamine release under DNP-IgE/HSA treatment. Moreover, IL-37 treatment also significantly restrained NF-κB activation and P38 phosphorylation in ACD RPMCs. SIS3, a specific Smad3 inhibitor, abolished the suppressive effects of IL-37 on MC-mediated allergic inflammation, suggesting the participation of Smad3 in the anti-ACD effect of IL-37. These findings indicated that IL-37 protects against IL-33-regulated MC inflammatory responses via inhibition of NF-κB and P38 MAPK activation accompanying the regulation of Smad3 in rats with ACD.     

β‐eudesmol suppresses allergic reactions via inhibiting mast cell degranulation

The regulatory effect of β‐eudesmol, which is an active constituent of Pyeongwee‐San (KMP6), is evaluated for allergic reactions induced by mast cell degranulation. Phorbol 12‐myristate 13‐acetate (PMA) plus calcium ionophore A23187‐stimulated human mast cell line, HMC‐1 cells, and compound 48/80‐stimulated rat peritoneal mast cells (RPMCs) are used as the in vitro models; mice models of systemic anaphylaxis, ear swelling, and IgE‐dependent passive cutaneous anaphylaxis (PCA) are used as the in vivo allergic models. The results demonstrate that β‐eudesmol suppressed the histamine and tryptase releases from the PMA plus calcium ionophore A23187‐stimulated HMC‐1 cells. β‐eudesmol inhibits the expression and activity of histidine decarboxylase in the activated HMC‐1 cells. In addition, β‐eudesmol inhibits the levels of histamine and tryptase released from the compound 48/80‐stimulated RPMCs. Furthermore, β‐eudesmol decreases the intracellular calcium level in the activated RPMCs. β‐eudesmol also decreases the compound 48/80‐induced mortality and ear swelling response. β‐eudesmol suppresses the serum levels of histamine, IgE, interleukin (IL)‐1β, IL‐4, IL‐5, IL‐6, IL‐13, and vascular endothelial growth factor (VEGF) under PCA mice as well as PCA reactions. Therefore, the results from this study indicate the potential of β‐eudesmol as an anti‐allergic drug with respect to its pharmacological properties against mast cell‐mediated allergic reactions.     

Induction of interleukin 8 release from the HMC-1 mast cell line: synergy between stem cell factor and activators of the adenosine A(2b) receptor

The HMC-1 mast cell line has both adenosine A(3) and A(2b) receptors on its surface, but only agonists of the A(2b) receptor are effective at releasing interleukin 8. Object of this study was to look for co-factors for adenosine A(2b) receptor activation. There was a powerful and statistically significant synergy for release of IL-8, both at the mRNA level (measured after 4 hr) and protein level (measured after 24 hr), between adenosine A(2b) receptor agonists and stem cell factor (SCF). Suitable concentrations for showing synergy were 100 ng/mL SCF and 3 microM 5'-N-ethylcarboxamidoadenosine (NECA). At these concentrations, the IL-8 released into the culture medium after SCF and NECA together was typically 3-5-fold greater in amount than the sum of the amounts of IL-8 released after exposure to the same concentrations of NECA and SCF separately. Since mast cells may be exposed to both adenosine and stem cell factor in the diseased lung, the synergy observed in this model system may have implications for asthma.     

Rubus croceacanthus Leveille inhibits mast cell-mediated anaphylactic-like reaction and tumor necrosis factor-alpha secretion

This work aims at examining the effect of the concentrated methanol extract of Rubus croceacanthus Leveille (RCL) on mast cell-mediated anaphylactic-like reaction in a murine model. RCL inhibited compound 48/80-induced systemic anaphylactic-like reaction. When RCL was given as pre-treatment at concentrations ranging from 0.01 to 1 mg/ml, the histamine release from rat peritoneal mast cells induced by compound 48/80 or anti-dinitrophenyl (DNP) immunoglobulin E (IgE) was reduced in a dose-dependent manner. RCL also inhibited passive cutaneous anaphylaxis activated by anti-DNP IgE. In addition, RCL inhibited phorbol 12-myristate 13-acetate and A23187-induced tumor necrosis factor-alpha secretion from human mast cell line HMC-1 cells. These results indicate that RCL may possess a strong anti-anaphylactic activity.     

Characterization of FPL-52694 [5-(2-hydroxypropoxyl)-8-propyl-4-oxo-4H-benzopyran-2-carboxylic acid Na] on histamine release from rat peritoneal mast cells induced by antigen, compound 48/80 and A 23187

We studied the in vitro effects of FPL-52694 [5-(2-hydroxypropoxyl)-8-propyl-4-oxo-4H-benzopyran-2-carboxylic acid Na] on histamine release from rat peritoneal mast cells. These cells exposed to ascaris antigen, compound 48/80 or the ionophore A 23187 concentration-dependently released histamine. About a 30-40% histamine release was obtained by 1 X 10(-4) g/ml of antigen, 1 X 10(-7) g/ml of compound 48/80 and A 23187. FPL-52694 (10(-9)-10(-4) g/ml) concentration-dependently inhibited the histamine release from mast cells in response to antigen (1 X 10(-4) g/ml) and compound 48/80 (1 X 10(-7) g/ml), but only slightly inhibited the histamine release induced by A 23187 (1 X 10(-7) g/ml). Similar results were obtained with disodium cromoglycate (DSCG), in the same dose ranges. However, the inhibitory activity of FPL-52694 on histamine release by antigen and compound 48/80 was approximately 10 times more potent than that of DSCG at certain concentrations. Tachyphylaxis was observed when these two agents were preincubated with mast cells for 10 min. These results show FPL-52694 to be a novel mast cell stabilizer.     

The effect of ethanol administration into the mouse on mast cell histamine releasability in vitro

Both chronic and acute ethanol administration to the mice (resulting in blood ethanol level 74.0 +/- 8.0 and 79.2 +/- 8.7 mM respectively) induced partial inhibition of in vitro histamine secretion from their peritoneal mast cells challenged with anti-mouse IgE or concanavalin A. An inhibiting effect of chronic ethanol administration was not observed when mast cells were in vitro challenged with calcium ionophore A23187. The results may suggest that ethanol intoxication of the mice inhibits in vitro anaphylactic histamine release from their peritoneal mast cells by the alteration of an early stage of biochemical processes leading to the opening of calcium channels in cell membrane and subsequent mediator secretion.     

Mast cell involvement in the adenosine mediated airway hyper-reactivity in a murine model of ovalbumin-induced lung inflammation

Airway hyper-reactivity to inhaled adenosine, mediated via mast cell activation, is a cardinal feature of asthma. Animal models have been developed in several species to mimic this phenomenon, but only in the rat has a mast cell involvement been clearly defined. In this study, a model of ovalbumin-induced adenosine hyper-reactivity was developed in BALB/c mice to determine whether mast cells are involved in this phenomenon. Sensitised mice were challenged one, two or three times, on a daily basis, and airway responses to the stable adenosine analogue NECA (5'-N-ethylcarboxamido adenosine) determined 4 and 24 h after each challenge. Airway hyper-reactivity was observed in ovalbumin-challenged mice 4 h after a single challenge and to a minor extent 24 h after a single challenge and 4 h after two challenges. Cromolyn (20 mg ml(-1)), given by aerosol an hour before the NECA provocation, fully inhibited the airway hyper-reactivity observed 4 h after a single allergen challenge, suggesting a role for mast cells in this response. The airway space cellular inflammation was not affected by cromolyn. As observed in human asthma, an acute treatment with steroid (budesonide 3 mg kg(-1), given an hour before the allergen challenge) inhibited the NECA airway hyper-reactivity and significantly inhibited the airway space cellular inflammation. These data suggest that the ovalbumin-challenged BALB/c mice can be considered as a suitable model to study the adenosine-induced airway hyper-reactivity phenomenon observed in human asthma.     

Stem cell factor: a hemopoietic cytokine with important targets in asthma

We review evidence that Stem Cell Factor (SCF) plays an important role in the pathophysiology of asthma. SCF is produced by a wide variety of cells present in asthmatic lung, including mast cells and eosinophils. Its receptor, c-kit, is broadly expressed on mature mast cells and eosinophils. SCF promotes recruitment of mast cell progenitors into tissues, as well as their local maturation and activation. It also promotes eosinophil survival, maturation and functional activation. SCF enhances IgE-dependent release of mediators from mast cells, including histamine, leukotrienes, cytokines (TNF-alpha, IL-5, GM-CSF) and chemokines (RANTES/CCL5, MCP-1/CCL2, TARC/CCL17 e MDC/CCL22); it is required for IL-4 production in mast cells. SCF, acting in concert with IgE, also upregulates the expression and function of CC chemokine receptors in mast cells. Structural and resident airway cells express increased levels of SCF in the bronchus of asthmatic patients. In a murine model of asthma, allergen exposure increased production of SCF by epithelial cells and alveolar macrophages, which was transient and paralleled by histamine release. SCF induced long-lived airway hyperreactivity, which was prevented by local neutralization of SCF, as well as by inhibitors of the production or activity of cysteinyl-leukotrienes. Together, these observations suggest that SCF has an important role in asthma.     

Meliae cortex extract exhibits anti-allergic activity through the inhibition of Syk kinase in mast cells

The anti-allergic action of various Oriental medicinal herbs was investigated using in vitro and in vivo experimental models. Of these extracts, the ethanol extract of Meliae cortex (MC) exhibited the most potent activity in mast cells; its IC(50) values were 29+/-1.5 microg/ml for antigen stimulation and 57+/-3.4 microg/ml for thapsigargin stimulation. It inhibited compound-48/80-induced systemic anaphylaxis by 52.9% at a dose of 300 mg/kg in mice; it also inhibited the expression of the proinflammatory mediator TNF-alpha. With regard to its mechanism of action, MC suppressed the activating phosphorylation of Syk, a key enzyme in mast-cell signaling processes and that of Akt in a dose-dependent manner. It also inhibited the MAP kinase ERK1/2, which is critical for the production of inflammatory cytokines in mast cells, as indicated by the suppression of the activating phosphorylation of ERK1/2. Taken together, these results suggest that the anti-allergic activity of MC may be due to the inhibition of histamine secretion and cytokine expression through the Syk inhibition in mast cells.