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)

Asthma bronchiale (a.b.) is defined as paroxysmal or permanent, partly or completely reversible dyspnoea due to a bronchospasm resulting from pathological hyperreactivity of the bronchial system. In the pathogenesis participate allergic, immuno-infiltrative and genetic factors, irritating substances (environment) and infectious. The allergic constituent acts via sensitization and allergization of the mast cell, to its degranulation with release of mediators (histamine, serotonin, leukotrienes, thromboxane, PAF) with subsequent bronchoconstriction and production of viscous mucus. As to adrenergic factors, a block of beta-adrenergic receptors and reduced adrenal function is involved. As to non-adrenergic factors an increased sensitivity of the parasympathetic--vagus is involved which conditions bronchoconstriction and hyperkrinia. From the clinical aspect extrinsic (atopic) and intrinsic (cryptogenic) asthma bronchiale can be differentiated. The former is encountered more frequently in childhood and adolescence, in subjects with a positive family-history, high IgE and positive skin tests and a known allergen. The latter type of a.b. is found in adolescence, in subjects with a negative family-history, with eosinophilia; it is conditioned by infection (e.g. chronic bronchitis), strain, cold and takes a dangerous course (aspirin). As to the course, attacks of a.b. are involved with a symptom-free interval (extrinsic a.) easily controlled by treatment. Then there is the chronic form with a variable course and the necessity of permanent treatment. Status asthmaticus is in recent years with increasing frequency the cause of death and thus calls for maximal treatment. It is the third most serious form of a.b. Assessment of arterial blood gases is very important as a check of treatment as well as from the prognostic aspect (cross-over intubation). From the differential diagnostic aspect we must consider the asthmoid component in chronic bronchitis, pulmonary embolism, left-sided cardiac failure, tracheal or bronchial compression by an aortal aneurysm, tumour. The differential diagnosis is not always easy.
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PMID:[Bronchial asthma. Pathogenesis and clinical aspects]. 145 62

Asthma is characterised by bronchial hyperresponsiveness. This feature of the asthmatic diathesis predisposes patients to wheezing in response to a number of different factors. These precipitating factors include specific allergen acting via sensitised mediator cells through an IgE-dependent mechanism. There are irritants which may work through a non-specific manner, or stimuli such as exercise and hyperventilation, which probably also act through mediator release via a non-IgE-dependent manner. The mechanism whereby physical stimuli such as exercise induce bronchoconstriction is of interest, because it increases the context in which the mast cell may participate in acute asthmatic bronchoconstriction. Respiratory infections also commonly provoke asthma, especially in infants and may, indeed, precipitate the asthmatic state itself. Finally, drugs can often trigger asthma attacks and the mechanisms of asthma precipitated by non-steroidal anti-inflammatory drugs such as aspirin have been the subject of recent research.
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PMID:Precipitating factors of asthma. 161 89

Asthma is characterized by airway inflammation and hyper-responsiveness. Clinically, these features are manifested by attacks of cough, wheezing, and dyspnoea. Nocturnal asthma symptoms are frequent; 39% of asthmatics awaken nightly, and 94% have nocturnal awakenings at least once a month. A number of mechanisms have been hypothesized to explain the phenomenon of nocturnal asthma, including exposure to dust mite allergen, late-phase allergic reactions, effects of posture and sleep stage on airway tone, gastro-oesophageal reflex, impaired mucociliary clearance, airway cooling, and changes in circadian rhythms of circulating hormones. While no single mechanism can explain these changes, circadian rhythms may be particularly relevant. Normal airway tone increases during sleep and is magnified in asthmatics. Bronchial responsiveness to histamine and allergen challenge increases during sleep and mast cell mediator release is enhanced. Circulating eosinophils increase, which may allow their ingress into pulmonary tissue. Decreases in plasma catecholamine and cortisol levels have also been observed. All of these may influence airway tone, inflammation, and responsiveness during sleep and produce the observed clinical picture. Inhaled sympathomimetics are frequently ineffective in preventing nocturnal symptoms due to their short duration of action. While corticosteroids, cromoglycate, and anticholinergics are effective, sustained-release theophylline is particularly advantageous for controlling nocturnal symptoms. Once-daily theophylline when dosed in the evening not only controls nocturnal symptoms and improves airflow during the early morning hours, but decreases airway responsiveness to histamine as well. The close association between airway inflammation, airway hyper-responsiveness, and nocturnal asthma symptoms makes further studies of the mechanism of action of theophylline especially interesting.
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PMID:Nocturnal asthma: mechanisms and the role of theophylline in treatment. 175 31

Inadequate reactions of the immune system, i.e. allergic or hypersensitivity reactions, may lead to lung tissue injury and possibly airway hyperreactivity. In extrinsic asthma, mast cells are considered to play a pivotal role in inducing hyperreactivity by producing various mediators. Immunoglobulin E is a well-known inducer of mast cell mediator release, and is thus often considered important. Asthma induced by a small molecular moiety such as toluene diisocyanate (TDI) is only in 15% of patients associated with increased IgE levels. TDI is a known inducer of cellular immune responses. We are investigating the relationship of type IV hypersensitivity, as an example of IgE-independent cellular hypersensitivity, with the induction of airway hyperreactivity. We have studied mice which were sensitized with picryl chloride. After antigen challenge in such sensitized mice, peribronchial and perivascular accumulation of macrophages and lymphocytes was highest 48 h after challenge. Two hours after challenge and from 7 days onwards no infiltration was found. At several time points after challenge, changes in smooth muscle tone of mouse tracheas were measured isometrically. The response to carbachol increased from 2 h after challenge, reaching a maximum 48 h after challenge and lasted for at least 3 weeks. This hyperreactivity was not found in athymic (nude) mice. We conclude from these preliminary data that airway hyperreactivity can be immunologically induced other than by IgE, and that in this model it is not associated with the presence of a mononuclear infiltrate. These experimental data indicate a potential role for T cells in inducing airway hyperreactivity, a common denominator of patients suffering from asthma.
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PMID:T cell-mediated airway hyperreactivity in mice. 195 13

Sympathomimetic bronchodilators with preferential specificity for the beta-2 receptor subtype are routinely used in asthma therapy. In addition to their ability to dilate bronchial smooth muscle following beta-2 receptor stimulation, these agents also inhibit mast cell mediator release and alter airway responsiveness. The importance of this class of drugs in asthma therapy has prompted the development of multiple asthma agents with the hope of achieving greater beta-2 receptor specificity, a quicker onset or more prolonged duration of action, a greater peak effect, or fewer side effects. This review compares the beta-2 agonists, as a group, with other asthma medications and, when data are available, makes comparison among various drugs within the group.
J Asthma 1990
PMID:Beta-2 receptor agonists in asthma: a comparison. 197 21

A diagrammatic representation of the interactions between mediators of hypersensitivity and leukocytes in early, late-phase, and ongoing asthma is shown in Figure 1. Early phase or immediate reactions are largely the result of bronchoconstriction consequent to the release of mediators such as histamine, PGD2, LTC4/D4, and PAF. The principal mediator cell (MC) is the mast cell (although other IgE receptor-bearing cells such as the macrophage, eosinophil, and platelet might also be involved in this immediate response). The stimulus for mediator cell activation may be either immunologic (IgE-dependent) or nonimmunologic (i.e., changes in osmolarity as a result of the respiratory water loss associated with exercise-induced asthma). Late-phase reactions appear to be a consequence of infiltration with neutrophils (N), eosinophils (E), and macrophages (M phi). These cells are recruited and activated either by mast cell-associated chemotactic factors [such as LTB4, PAF, the eosinophil chemotactic factor of anaphylaxis (ECF-A), or high-molecular weight neutrophil chemotactic activity (NCA (HMW))] and/or "lymphokines" derived from T-helper cells (TH) which have been stimulated by antigen processed by the antigen-processing cells (APC). These mononuclear cell interactions are under the control of regulatory T cells [T suppressor (TS) cells] and it is speculated that the availability of these subsets may determine the magnitude of the late-phase response. Lymphokines and monokines which selectively activate neutrophils, eosinophils, and monocytes include LIF, EAF, and IFN-gamma, respectively. Macrophage-derived tumor necrosis factor (TNF) also amplifies the inflammatory response by its capacity to enhance eosinophil cytotoxicity.(ABSTRACT TRUNCATED AT 250 WORDS)
J Asthma 1989
PMID:Inflammatory cells in bronchial asthma. 270 38

Asthma is a disease of the airways that results in reversible airflow obstruction. Recent investigations have suggested that airway inflammation is associated with increased airway responsiveness and worsening of asthmatic symptoms. The role that mast cell mediators might play in the production of asthma has been investigated by use of newer analytical techniques and by use of fiberoptic bronchoscopy with lavage to obtain lower respiratory tract fluid and cells. In addition, new investigational compounds that interfere with the synthesis or action of inflammatory mediators have been tested. Developing lines of investigation suggest that chronic activation of inflammatory cells may be important in the pathogenesis of asthma.
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PMID:Asthma: emerging concepts and potential therapies. 288 84

Nasal polyps are a condition of uncertain aetiology but are associated with diseases of the lower respiratory tract, in particular, asthma and cystic fibrosis. Asthma may be mediated by mast cell reactions and the commonest allergen to degranulate mast cells is house dust mite. Mast cells have been shown to be degranulated in nasal polyps. This study looks at thirty-six patients who had nasal polypectomy and of whom fourteen were asthmatic to see if histamine was released from polyp tissue and peripheral blood when they were challenged with antihuman IgE and extracts of house dust mite and mixed grass pollens. These results were compared with skin tests to these allergens. A release of above 15 per cent of the total histamine was considered positive. Eight patients released histamine from polyp tissue but only three patients released histamine with both anti IgE and allergen extracts. The release from blood compared well with positive skin tests (p greater than 0.05 corrected chi square). Although allergy may cause mast cell degranulation in polyp tissue, this study suggests that it is unlikely to be a common cause of nasal polyps.
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PMID:The release of histamine from nasal polyp tissue and peripheral blood when challenged with antihuman IgE, house dust mite extract and mixed grass pollen extract and compared with positive skin tests. 319 7

The principal pathological features of asthma, including tracheobronchial smooth muscle contraction and mast cell mediator synthesis and release, are calcium-dependent processes. Calcium plays an integral role in transmitting signals at the cell surface to the enzymatic machinery of the cell interior; its role as the agent for "excitation-contraction coupling" of airway smooth muscle and for "stimulus-secretion coupling" of mast cells is reviewed. A rise in intracellular calcium ion concentration triggers cellular activation. In smooth muscle, calcium bound to calmodulin stimulates the myosin light chain kinase which is important in the regulation of actin-myosin interaction. In mast cells, calcium may bind to calmodulin or to a calmodulinlike regulatory protein, and it also stimulates enzymes important in the synthesis of newly generated mediators including prostaglandins and leukotrienes. The regulatory role of cyclic AMP in both cell systems is discussed, especially as it pertains to calcium metabolism. By interfering with transmembrane calcium fluxes, the calcium channel blocking drugs have the potential for significantly modifying bronchoconstriction and airway inflammation in asthma and related bronchospastic disorders. Some of the in vitro studies of calcium channel blockers in these two cell systems are reviewed. Finally a speculation about the role of abnormal sensitivity to calcium in airway smooth muscle as a potential cause of airway hyperreactivity is entertained.
J Asthma 1984
PMID:Role of calcium in airway smooth muscle contraction and mast cell secretion. 608 60

A variety of clinical and animal bronchial challenge experiments have been undertaken to assess the efficacy and sites of action of the calcium channel blockers nifedipine and verapamil in blunting bronchoconstriction. Nifedipine appears to be the more effective of these agents, and it blunts the airways response to methacholine and histamine inhalation as well as the bronchoconstriction caused by exercise or cold air hyperpnea. The mechanism by which it acts is difficult to define with certainty because of the widely distributed role of calcium ion within the bronchoconstriction pathways, but nifedipine appears to exert a direct effect on airway wall smooth muscle as well as a possible influence on mast cell mediator release.
J Asthma 1984
PMID:Calcium channel blocking agents in bronchial hyperreactivity. 639 94


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