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Mast Cell Stabilization (mast_cell + stabilization)
Selected AbstractsAlterations of intestinal motor responses to various stimuli after Nippostrongylus brasiliensis infection in rats: role of mast cellsNEUROGASTROENTEROLOGY & MOTILITY, Issue 3 2000J. Gay Nippostrongylus brasiliensis infection induces jejunal mastocytosis associated with enteric nerve remodelling in rats. The aim of this study was to evaluate the intestinal motility responses to meals and to neurotransmitters involved in the control of gut motility (acetylcholine (carbachol), substance P and neurokinin A) in both control and N. brasiliensis -infected rats 30 days post-infection. All rats were equipped with NiCr electrodes in the jejunum to record myoelectrical activity. The duration of disruption of the jejunal migrating myoelectrical complexes (MMC) induced by the different stimuli was determined. Meal ingestion and substance P administration disrupted the MMC pattern for similar durations in the two groups. Carbachol and neurokinin A induced a significantly longer MMC disruption in post-infected rats than in controls (125 ± 8.3 vs. 70 ± 6 min for carbachol 100 ,g kg,1 and 51 ± 4 vs. 40 ± 2 for neurokinin A 50 ,g kg,1). The enhanced motor response in postinfected rats was reduced by previous mast cell stabilization with ketotifen or mast cell degranulation with compound BrX 537 A. In conclusion, the increased intestinal motor reactivity to carbachol and neurokinin A in post- N. brasiliensis -infected rats depends upon intestinal mast cell hyperplasia and degranulation. [source] Targeted mast cell silencing protects against joint destruction and angiogenesis in experimental arthritis in miceARTHRITIS & RHEUMATISM, Issue 6 2007Manfred Kneilling Objective Induction of arthritis with autoantibodies against glucose-6-phosphate isomerase (GPI) is entirely independent of T cells and B cells but is strictly dependent on the presence of mast cells. Here, we used this disease model to analyze whether exclusive intraarticular mast cell reconstitution is sufficient for disease induction and whether targeted mast cell silencing can prevent neoangiogenesis and joint destruction, 2 hallmarks of rheumatoid arthritis. Methods Ankle swelling and clinical index scores were determined after injection of either K/BxN mouse,derived serum or control serum in wild-type Kit+/Kit+ mice, congenic mast cell,deficient KitW/KitW - v mice, or mast cell,deficient KitW/KitW - v mice reconstituted with mast cells, either by intraperitoneal or selective intraarticular injection. Angiogenesis was quantified in vivo by measuring activated ,v,3 integrin using 18F,galacto-RGD and positron emission tomography. In addition, staining of joint tissue with hematoxylin and eosin, Giemsa, ,3, and ,-actin was performed. The effect of mast cell stabilization by treatment with cromolyn or salbutamol was investigated in C57BL/6 or BALB/c mice. Results Comparing wild-type mice, mast cell,deficient KitW/KitW - v mice, and mast cell,reconstituted KitW/KitW - v mice, we first showed that intraarticular and intraperitoneal mast cell engraftment fully restores susceptibility to antibody-induced arthritis, angiogenesis, and ,v,3 integrin activation. Importantly, selective mast cell silencing with either salbutamol or cromolyn prevented ,v,3 integrin activation, angiogenesis, and joint destruction. Conclusion Mast cell engraftment fully restores susceptibility to ,v,3 integrin activation, angiogenesis, and joint destruction in GPI antibody,induced arthritis. Importantly, selective mast cell stabilization prevents ,v,3 integrin activation, angiogenesis, and joint destruction. [source] The long-acting ,-adrenoceptor agonist, indacaterol, inhibits IgE-dependent responses of human lung mast cellsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2009Anne-Marie Scola Background and purpose:, The long-acting ,2 -adrenoceptor agonist, indacaterol, has been developed as a bronchodilator for the therapeutic management of respiratory diseases. The aim of the present study was to determine whether indacaterol has any anti-inflammatory activity. To this end, the effects of indacaterol on human lung mast cell responses were investigated. Experimental approach:, The effects of indacaterol, and the alternative long-acting ,-agonists formoterol and salmeterol, were investigated on the IgE-dependent release and generation of histamine, cysteinyl-leukotrienes and prostaglandin D2 from human lung mast cells. Moreover, the extent to which long-term (24,72 h) incubation of mast cells with long-acting ,-agonists impaired the subsequent ability of ,-agonists to inhibit mast cell responses was assessed. Key results:, Indacaterol was as potent and as efficacious as the full agonist, isoprenaline (EC50, ,4 nmol·L,1), at inhibiting the IgE-dependent release of histamine from mast cells. Formoterol was a full agonist whereas salmeterol was a partial agonist as inhibitors of histamine release. All three long-acting ,-agonists were effective inhibitors of the IgE-dependent generation of cysteinyl-leukotrienes and prostaglandin D2. Long-term incubation of mast cells with long-acting ,-agonists led to a reduction in the subsequent ability of ,-agonists to stabilize mast cell responses. This tendency to induce functional desensitization was least evident for indacaterol. Conclusions and implications:, Indacaterol is an effective inhibitor of the release of mediators from human lung mast cells. This suggests that, as well as bronchodilation, mast cell stabilization may constitute an additional therapeutic benefit of indacaterol. [source] |