leukotriene-c4 and Asthma

Leukotriene (LT) E(4) mediates many of the principal features of bronchial asthma, such as bronchial constriction, hyperresponsiveness, eosinophilia, and increased vascular permeability. Furthermore, it is the most stable of the cysteinyl leukotrienes (CysLTs) and can be active at the site of release for a prolonged time after its synthesis. There might be several reasons why LTE(4) has been forgotten. LTE(4) demonstrated low affinity for CysLT(1) and CysLT(2) receptors in equilibrium competition assays. It was less potent than other CysLTs in functional assays, such as calcium flux, in cells transfected with CysLT(1) and CysLT(2). The introduction of CysLT(1) antagonists into clinical practice diverted interest into CysLT(1)-related mechanisms, which were mediated mainly by LTD(4). However, experiments with animal models and human studies have revealed that LTE(4) has unique characteristics that cannot be explained by the current knowledge of CysLT(1) and CysLT(2). These activities include its potency relative to other CysLTs to increase airway responsiveness to histamine, to enhance eosinophilic recruitment, and to increase vascular permeability. Asthmatic airways also demonstrate marked in vivo relative hyperresponsiveness to LTE(4), especially in patients with aspirin-sensitive respiratory disease. This has stimulated a search for additional LT receptors that would respond preferentially to LTE(4) stimulation.

Topics: Animals; Aspirin; Asthma; Bronchial Hyperreactivity; Drug Hypersensitivity; Histamine; Humans; Leukotriene C4; Leukotriene D4; Leukotriene E4; Methacholine Chloride; Receptors, Leukotriene; Skin

The intracellular parent of the cysteinyl leukotrienes (cysLTs), leukotriene (LT) C(4), is formed by conjugation of LTA(4) and reduced glutathione by LTC(4) synthase in mast cells, eosinophils, basophils, and macrophages. After extracellular export, LTC(4) is converted to LTD(4) and LTE(4) through sequential enzymatic removal of glutamic acid and then glycine. Only LTE(4) is sufficiently stable to be prominent in biologic fluids, such as urine or bronchoalveolar lavage fluid, of asthmatic individuals and at sites of inflammation in animal models. LTE(4) has received little attention because it binds poorly to the classical type 1 and 2 cysLT receptors and is much less active on normal airways than LTC(4) or LTD(4). However, early studies indicated that LTE(4) caused skin swelling in human subjects as potently as LTC(4) and LTD(4), that airways of asthmatic subjects (particularly those that were aspirin sensitive) were selectively hyperresponsive to LTE(4), and that a potential distinct LTE(4) receptor was present in guinea pig trachea. Recent studies have begun to uncover receptors selective for LTE(4): P2Y(12), an adenosine diphosphate receptor, and CysLT(E)R, which was observed functionally in the skin of mice lacking the type 1 and 2 cysLT receptors. These findings prompt a renewed focus on LTE(4) receptors as therapeutic targets that are not currently addressed by available receptor antagonists.

Topics: Animals; Asthma; Guinea Pigs; Humans; Leukotriene Antagonists; Leukotriene C4; Leukotriene D4; Leukotriene E4; Mice; Receptors, Leukotriene; Receptors, Purinergic P2; Skin

Cysteinyl-leukotrienes (cysteinyl-LTs), that is, LTC4, LTD4, and LTE4, trigger contractile and inflammatory responses through the specific interaction with G protein-coupled receptors (GPCRs) belonging to the purine receptor cluster of the rhodopsin family, and identified as CysLT receptors (CysLTRs). Cysteinyl-LTs have a clear role in pathophysiological conditions such as asthma and allergic rhinitis (AR), and have been implicated in other inflammatory conditions including cardiovascular diseases, cancer, atopic dermatitis, and urticaria. Molecular cloning of human CysLT1R and CysLT2R subtypes has confirmed most of the previous pharmacological characterization and identified distinct expression patterns only partially overlapping. Interestingly, recent data provide evidence for the immunomodulation of CysLTR expression, the existence of additional receptor subtypes, and of an intracellular pool of CysLTRs that may have roles different from those of plasma membrane receptors. Furthermore, genetic variants have been identified for the CysLTRs that may interact to confer risk for atopy. Finally, a crosstalk between the cysteinyl-LT and the purine systems is being delineated. This review will summarize and attempt to integrate recent data derived from studies on the molecular pharmacology and pharmacogenetics of CysLTRs, and will consider the therapeutic opportunities arising from the new roles suggested for cysteinyl-LTs and their receptors.

Topics: Adult; Animals; Asthma; Cardiovascular Diseases; Child; Child, Preschool; Dermatitis, Atopic; Female; Humans; Hydroxyurea; Leukotriene Antagonists; Leukotriene C4; Leukotriene D4; Leukotriene E4; Membrane Proteins; Pharmacogenetics; Receptors, Leukotriene; Receptors, Purinergic; Recombinant Proteins; Rhinitis, Allergic, Seasonal; SRS-A; Tissue Distribution

Topics: Arachidonic Acid; Aspirin; Asthma; Desensitization, Immunologic; Drug Hypersensitivity; Humans; Inflammation; Leukotriene C4; Nasal Polyps; Prostaglandin-Endoperoxide Synthases; Rhinitis; Sinusitis

Twenty five years after the structure elucidation of slow reacting substance of anaphylaxis, antileukotrienes are established as a new therapeutic modality in asthma. The chapter reviews the biochemistry and pharmacology of leukotrienes and antileukotrienes with particular focus on the different usage of antileukotrienes for treatment of asthma and rhinitis in Europe and the US. Further research needs and new areas for leukotriene involvement in respiratory diseases are also discussed.

Topics: Acetates; Animals; Asthma; Clinical Trials as Topic; Cyclopropanes; Humans; Hydroxyurea; Leukotriene Antagonists; Leukotriene C4; Leukotriene D4; Leukotriene E4; Lipoxygenase Inhibitors; Membrane Proteins; Quinolines; Receptors, Leukotriene; Respiratory System; Rhinitis; Sulfides

Topics: Asthma; Bronchial Hyperreactivity; Humans; Interleukin-16; Leukotriene C4

Topics: Asthma; Biomarkers; Chromatography, High Pressure Liquid; Humans; Inflammation Mediators; Leukotriene B4; Leukotriene C4; Leukotriene D4; Leukotriene E4; Radioimmunoassay; Reference Values; Specimen Handling; Status Asthmaticus

Topics: Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Asthma; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Dinoprostone; Humans; Isoenzymes; Leukotriene C4; Membrane Proteins; Prostaglandin-Endoperoxide Synthases

Topics: Asthma; Humans; Leukotriene B4; Leukotriene C4; Leukotriene D4; Leukotriene E4

Eosinophils are prominent features of allergic inflammation and can contribute to this process through release of inflammatory enzymes, granule-associated proteins, and leukotriene products. There is considerable interest in the fact that selected cytokines enhance eosinophil generation of leukotrienes. Therefore, future directions must include efforts to identify factors that regulate eosinophil synthesis of leukotrienes and therapeutic agents that might control these specific inflammatory responses.

Topics: Asthma; Cysteine; Eosinophils; Humans; Hypersensitivity; Leukotriene C4; Leukotrienes; Respiratory Tract Diseases

Topics: Animals; Arachidonate 5-Lipoxygenase; Asthma; Bronchial Hyperreactivity; Cell Adhesion Molecules; Eosinophils; Humans; Leukotriene C4; Neutrophils

The number of Sp1-Egr1 binding tandem repeats at the ALOX5 promoter influences gene transcription and may modify the response to anti-leukotriene treatment. The relationship of ALOX5 variants to asthma severity and leukotriene production by eosinophils is unknown.. To characterize ALOX5 mRNA expression and cysteinyl-leukotriene production by eosinophils from individuals bearing ALOX5 promoter deletional variants and their association with the severity of childhood asthma.. Eosinophils from adult asthmatics bearing only variant alleles (with other than five tandem repeats on both chromosomes, non5/non5) or no variant alleles (5/5) were cultured in vitro and ALOX5 expression and leukotriene secretion were measured. A total of 621 children with mild or moderate-severe asthma were genotyped at the ALOX5 core promoter.. Asthmatics with non5/non5 genotype expressed less ALOX5 mRNA and produced less LTC4 into culture supernatants than 5/5 individuals (6.4 +/- 2.0 and 20.0 +/- 5.0 pg/ml, n = 5; P < 0.05). More asthmatic children bearing non5/non5 genotype had moderate-severe asthma than children with the 5/5 genotype (5.3% vs. 1.4%, P = 0.008). Multivariate logistic regression identified ALOX5 promoter genotype as a significant predictor of disease severity (OR = 3.647, 95% CI: 1.146-11.608, P = 0.03). Consistent with these findings, children bearing the non5/non5 genotype had greater bronchomotor response to exercise as measured by the maximum fall after exercise and the area under the exercise curve (P < 0.05 for both).. Our results suggest that children who express the asthma phenotype despite having a genetic variant that impairs their ability to express ALOX5 have more severe disease and thus are more likely to have asthma symptoms.

Topics: Adolescent; Adult; Age Factors; Arachidonate 5-Lipoxygenase; Asthma; Cells, Cultured; Child; Female; Gene Expression Regulation; Genotype; Humans; Leukotriene C4; Male; Middle Aged; Probability; Prognosis; Promoter Regions, Genetic; Prospective Studies; Respiratory Function Tests; Risk Assessment; RNA, Messenger; Sensitivity and Specificity; Severity of Illness Index; Sex Factors; Single-Blind Method; Statistics, Nonparametric

Treatment with antileukotriene drugs results in clinical improvement in many, though not all, patients with asthma. It can be hypothesized that the subpopulation of asthmatic patients, characterized by aspirin intolerance and cysteinyl-leukotriene overproduction, might profit most from antileukotriene treatment.. We compared the clinical response to montelukast in two well-matched groups of patients with mild asthma: 26 aspirin-intolerant asthmatics (AIAs) and 33 aspirin-tolerant asthmatics (ATAs). We also searched for possible predictors of the clinical response among the parameters reflecting the expression and production of cysteinyl-leukotrienes (cys-LTs). This was an 8-week, single-blind, placebo-controlled trial.. Following a 3-week montelukast 10 mg day-1 treatment compared with placebo, there was a statistically significant reduction in the mean daytime and nocturnal asthma symptoms and beta 2-agonist use, as well as a significant improvement in the morning and evening peak expiratory flows and quality of life. Both groups showed a similar significant improvement in the parameters studied. Clinical response did not correlate with the baseline urinary LTE4 excretion level. Improvement of asthma was observed mostly in patients with a low baseline and non-IL-5 inducible expression of LTC4 synthase (LTC4S) mRNA in eosinophils. There was a trend toward a better response in carriers of LTC4S allele C, but no relationship to the CC10 genetic polymorphism.. No difference in the clinical response to the montelukast treatment was observed between the AIAs and the ATAs.

Topics: Acetates; Adult; Analysis of Variance; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Asthma; Cyclopropanes; Eosinophils; Female; Humans; Leukotriene Antagonists; Leukotriene C4; Lung; Male; Middle Aged; Peak Expiratory Flow Rate; Quinolines; Single-Blind Method; Statistics, Nonparametric; Sulfides

The effects of perilla seed oil (n-3 fatty acids) on bronchial asthma were compared with the effects of corn oil (n-6 fatty acids) in relation to the pulmonary function and the generation of leukotriene B4 (LTB4) and C4 (LTC4) by leucocytes.. 14 asthmatic subjects were divided randomly into two groups: one group (7 subjects) consumed perilla seed oil-rich supplementation and the other group (7 subjects) consumed corn oil-rich supplementation for 4 weeks. Generation of LTs by leucocytes and respiratory function were compared between the two groups.. The generation of LTB4 and LTC4 by leucocytes tended to increase in subjects (N=7) with corn oil-rich supplementation, and decrease in subjects (N=7) with perilla seed oil-rich supplementation. Significant differences between the two groups were observed in the generation of LTB4 at 2 weeks (p<0.05) and LTC4 at 2 weeks (p<0.05) after dietary supplementation. Significant increases in the value of PEF (p<0.05), FVC (p<0.01), FEV(1.0) (p<0.05) and V(25) (p<0.05) were found in subjects who received perilla seed oil supplementation for 4 weeks. And significant differences in the value of FVC (p<0.05) and FEV(1.0) (p<0.05) were observed between the two groups after 4 weeks of dietary supplementation.. These results suggest that perilla seed oil-rich supplementation is useful for the treatment of asthma in terms of suppression of LTB4 and LTC4 generation by leucocytes, and improvement of pulmonary function.

Topics: Adult; Aged; Aged, 80 and over; alpha-Linolenic Acid; Asthma; Biomarkers; Corn Oil; Dietary Fats, Unsaturated; Dietary Supplements; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Fatty Acids, Unsaturated; Female; Humans; Leukocytes; Leukotriene B4; Leukotriene C4; Male; Middle Aged; Plant Oils; Respiratory Function Tests; Treatment Outcome

Dietary sources of alpha-linolenic acid, such as perilla seed oil, may have the capacity to inhibit the generation of leukotrienes (LTs) by leucocytes in patients with asthma, as has been reported with the consumption of other long-chain n-3 fatty acids.. The factors affecting the suppression of leukotriene (LT) C4 generation by leucocytes were examined by comparing the clinical features of patients with asthma who had been given dietary perilla seed oil (n-3 fatty acids). Group A consisted of patients in whom the leucocyte generation of LTC4 was suppressed by dietary perilla seed oil. Group B consisted of those in whom LTC4 generation was not suppressed.. LTC4 generation by leucocytes decreased significantly in group A after 2 (p < 0.05) and 4 weeks (p < 0.05); conversely, it increased significantly in group B after 4 weeks (p < 0.05). The two study groups differed significantly in terms of LTC4 generation by leucocytes after 4 weeks of dietary supplementation (p < 0.05). Ventilatory parameters such as peak expiratory flow (PEF), forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV(1)) increased significantly after 4 weeks of dietary supplementation in group A (p < 0.05). Values of PEF, FVC, FEV(1) and maximum expiratory flow at 25% of the forced vital capacity (V(25)) differed significantly between groups A and B prior to dietary supplementation. Serum levels of total cholesterol, low-density lipoprotein (LDL) cholesterol and phospholipid were significantly decreased by dietary supplementation in group A after 4 weeks. Serum levels of total cholesterol, triglyceride, high-density lipoprotein cholesterol, LDL cholesterol and phospholipid differed significantly between the two study groups prior to dietary supplementation. Serum levels of triglyceride and LDL cholesterol differed significantly between the two study groups after 4 weeks of dietary supplementation.. Dietary supplementation with perilla seed oil in selected patients with asthma suppresses the generation of LTC4 and is associated with clinical features such as respiratory function and lipometabolism.

Topics: Adult; Aged; Aged, 80 and over; alpha-Linolenic Acid; Anticarcinogenic Agents; Asthma; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Dietary Supplements; Female; Forced Expiratory Volume; Humans; Leukocytes; Leukotriene C4; Lipids; Male; Maximal Midexpiratory Flow Rate; Middle Aged; Phospholipids; Plant Oils; Triglycerides; Vital Capacity

To estimate the effect of prednisolone on 5-lipoxygenase activity in eosinophils obtained from asthmatic patients, cytosolic levels of 5-H(P)ETE and Ca2+ were measured in the eosinophils which were exposed to prednisolone in vitro and in vivo. The mean level of 5-H(P)ETE during a wheezing attack was significantly lower in the patients who had received intravenous prednisolone (500 mg/day). Incubation with prednisolone in vitro caused a dose-dependent decrease in the cytosolic levels of 5-H(P)ETE and Ca2+ in eosinophils obtained during the wheezing attack, but not in the eosinophils obtained from during remission. Results suggest that prednisolone inhibits the level of 5-H(P)ETE in the eosinophil cytosols of asthmatic patients during a wheezing attack, probably by inhibition of 5-lipoxygenase activity which is involved in the reduction of the influx of Ca2+.

Topics: Adult; Arachidonic Acids; Asthma; Calcium; Cytosol; Dose-Response Relationship, Drug; Eosinophils; Glucocorticoids; Humans; Injections, Intravenous; Leukocyte Count; Leukotriene C4; Male; Middle Aged; Prednisolone; Remission Induction; Respiratory Sounds

Traditional Chinese medicines (TCM) have been used to treat bronchial asthma for several centuries and a certain degree of clinical benefit has been observed; however, scientific substantiation is lacking. A multicenter, double-blind and placebo-controlled study was therefore conducted to evaluate the clinical efficacy in terms of symptom score, medication score, morning and evening PEFRs, and changes of immunoregulatory function, such as distribution of lymphocyte subsets and in vivo and in vitro production of lymphokines (IFN-gamma and IL-4) and inflammatory mediators (histamine, PGE2 and LTC4). Furthermore, the protective effect of TCM on the late asthmatic reaction (LAR) was evaluated by using asthmatic guinea pigs. Three hundred and three asthmatic children were classified by Chinese doctors, according to a standardized questionnaire designed on the basis of basic logic of Chinese medicine, into three groups of specific constitution (group A, B and C). Group A consisted of 32 herb A-treated patients and 34 placebo-treated; group B, 74 herb B-treated and 64 placebo-treated; and group C, 55 herb C-treated and 44 placebo-treated. The study period was six months. The results were: 1) Both treatment group and placebo group showed an improvement in all clinical parameters, thus demonstrating a placebo effect. However, the improvement was usually greater in the former than the latter, although only the difference in PEFR was significant; 2) Herb A could increase total T cell and decrease B cell; 3) Herb A and B enhanced production of PGE2 but not LTC4, IFN-gamma and IL-4; 4) There was a general tendency for in vivo and in vitro production of histamine to decrease at the end of study in both treatment group and placebo group; however, the decrease was significantly greater in the former than the latter; 5) In asthmatic guinea pigs, 10-day's pretreatment with Chinese herbs could reverse the decrease of sGaw, suppress eosinophilia in bronchoalveolar lavage fluid (BALF), prevent the eosinophil infiltration of airways, increase PGE2 production and decrease LTC4 production in serum and BALF. Thus, traditional Chinese medicines did show a certain degree of clinical efficacy. The decreased production of histamine and LTC4, increased production of PGE2 that were found in both asthmatic children and asthmatic guinea pigs, and prevention of occurrence of LAR by suppressing eosinophil infiltration of airways and preserving airway conductance that were observed in asthm

Topics: Adolescent; Animals; Asthma; Bronchi; Bronchoalveolar Lavage Fluid; Child; Dinoprostone; Double-Blind Method; Drug Monitoring; Drugs, Chinese Herbal; Eosinophilia; Eosinophils; Female; Guinea Pigs; Histamine; Humans; Interferon-gamma; Interleukin-4; Kidney; Leukotriene C4; Lymphocyte Subsets; Male; Ovalbumin; Peak Expiratory Flow Rate; Severity of Illness Index; Spleen; Surveys and Questionnaires; Vaccination

Topics: Administration, Inhalation; Adult; Asthma; Beclomethasone; Double-Blind Method; Eosinophils; Female; Humans; Leukocyte Count; Leukotriene C4; Male; Methacholine Chloride

Topics: Animals; Anti-Allergic Agents; Asthma; Cytokines; Disease Models, Animal; Immunoglobulin E; Inflammation; Leukotriene B4; Leukotriene C4; Lung; Mice; Mice, Inbred BALB C; Mucoproteins; Respiratory Hypersensitivity

To study the effect of Hanchuan Zupa granule combined with conventional western medicine in the treatment of children with bronchial asthma.. 98 cases in Fengrun District People's Hospital of Tangshan City from June 2018 to February 2021 were selected. The control group was given oxygen therapy, antibiotics, and aerosol inhalation of quick acting. After treatment, the levels of sputum IL-4, IL-17, neu, and ECP in the two groups decreased, and the observation group was lower than the control group (. Bairui granule combined with conventional western medicine in the treatment of children with bronchial asthma, the curative effect is worthy of affirmation, can effectively improve cough symptoms, reduce EOS, CXCR, LTB4, SDF-1 levels, inhibit airway inflammation, and has good clinical application value.

Topics: Asthma; Child; Cough; Eosinophils; Humans; Inflammation Mediators; Leukotriene B4; Leukotriene C4; Sputum

Ecklonia cava is an edible marine brown alga harvested from the ocean that is widely consumed in Asian countries as a health-promoting medicinal food The objective of the present study is to evaluate the anti-asthma mechanism of a new functional food produced by bioprocessing edible algae Ecklonia cava and shiitake Lentinula edodes mushroom mycelia and isolated fractions.. We used as series of methods, including high performance liquid chromatography, gas chromatography, cell assays, and an in vivo mouse assay to evaluate the asthma-inhibitory effect of Ecklonia cava bioprocessed (fermented) with Lentinula edodes shiitake mushroom mycelium and its isolated fractions in mast cells and in orally fed mice.. The in vitro cell and in vivo mouse assays demonstrate the potential value of the new bioprocessed formulation as an anti-inflammatory and anti-allergic combination of natural compounds against allergic asthma and might also ameliorate allergic manifestations of foods, drugs, and viral infections.

Topics: Agaricales; Aluminum Oxide; Animals; Anti-Allergic Agents; Anti-Asthmatic Agents; Anti-Inflammatory Agents; Asthma; Cytokines; Immunoglobulin E; Inflammation; Interleukin-10; Leukotriene C4; Mice; Mice, Inbred BALB C; Mycelium; Ovalbumin; Phaeophyceae; Prostaglandin D2; Shiitake Mushrooms; Vascular Cell Adhesion Molecule-1

The 3 cysteinyl leukotrienes (cysLTs), leukotriene (LT) C. We sought to determine whether LTD. We used 2 different in vivo models of CysLT. LTC. The conversion of LTC

Topics: Animals; Asthma; Blood Platelets; Cysteine; Cytokines; Leukotriene C4; Leukotriene D4; Leukotriene E4; Leukotrienes; Lung; Male; Mice; Mice, Inbred C57BL; Platelet Activation; Pulmonary Eosinophilia; Receptors, Leukotriene

Topics: Animals; Anti-Allergic Agents; Anti-Asthmatic Agents; Anti-Inflammatory Agents; Asthma; Bone Marrow Cells; Cell Degranulation; Dermatitis, Atopic; Disease Models, Animal; Female; Immunoglobulin E; Lactones; Leukotriene C4; Mast Cells; Mice; Mice, Inbred BALB C; Ovalbumin; Phosphorylation; Respiratory Hypersensitivity; Sesquiterpenes; Signal Transduction

Asthma is a complex disease that is promoted by dysregulated immunity and the presence of many cytokine and lipid mediators. Despite this, there is a paucity of data demonstrating the combined effects of multiple mediators in asthma pathogenesis. Group 2 innate lymphoid cells (ILC2s) have recently been shown to play important roles in the initiation of allergic inflammation; however, it is unclear whether lipid mediators, such as cysteinyl leukotrienes (CysLTs), which are present in asthma, could further amplify the effects of IL-33 on ILC2 activation and lung inflammation. In this article, we show that airway challenges with the parent CysLT, leukotriene C4 (LTC4), given in combination with low-dose IL-33 to naive wild-type mice, led to synergistic increases in airway Th2 cytokines, eosinophilia, and peribronchial inflammation compared with IL-33 alone. Further, the numbers of proliferating and cytokine-producing lung ILC2s were increased after challenge with both LTC4 and IL-33. Levels of CysLT1R, CysLT2R, and candidate leukotriene E4 receptor P2Y12 mRNAs were increased in ILC2s. The synergistic effect of LTC4 with IL-33 was completely dependent upon CysLT1R, because CysLT1R

Topics: Allergens; Alternaria; Animals; Asthma; Cytokines; Eosinophilia; Immunity, Innate; Interleukin-33; Leukotriene C4; Lung; Lymphocyte Activation; Lymphocytes; Mice; Pneumonia; Receptors, Leukotriene; Receptors, Purinergic P2Y12; Th2 Cells

We previously demonstrated in mice that airway eosinophils traffic from the airway lumen into lung-draining paratracheal lymph nodes. However, mechanisms whereby eosinophils traverse from the lungs and home to paratracheal lymph nodes remain unclear. We investigated roles of cysteinyl leukotrienes in mediating eosinophil trafficking from lungs to paratracheal lymph nodes.. The expression of CCR7 was determined by flow cytometry. Transwell assays were used to test chemotactic responses of leukotriene C. Mouse eosinophils expressed CCR7, the receptor for CCL19, and responded chemotactically to CCL19. Leukotriene C. Our findings that cysteinyl leukotrienes are involved in regulating airway and lung eosinophil migration into paratracheal lymph nodes identify previously unrecognized roles for the cysteinyl leukotrienes in regulating the pulmonary trafficking of eosinophils in experimental allergic asthma.

Topics: Animals; Asthma; Chemokine CCL19; Chemotaxis; Eosinophils; Leukotriene C4; Lung; Lymph Nodes; Mice; Receptors, CCR7

Mushrooms can break down complex plant materials into smaller, more digestible and bioactive compounds. The present study investigated the antiasthma effect of an Ulmus parvifolia bark extract bioprocessed in Lentinus edodes liquid mycelium culture (BPUBE) against allergic asthma in chicken egg ovalbumin (OVA)-sensitized/challenged mice. BPUBE suppressed total IgE release from U266B1 cells in a dose-dependent manner without cytotoxicity. Inhibitory activity of BPUBE against OVA-specific IgE secretion in bronchoalveolar lavage fluid (BALF) was observed in OVA-sensitized/challenged asthmatic mice. BPUBE also inhibited OVA-specific IgG and IgG1 secretion into serum from the allergic mice, suggesting the restoration of a Th2-biased immune reaction to a Th1/Th2-balanced status, as indicated by the Th1/Th2 as well as regulatory T cell (Treg) cytokine profile changes caused by BPUBE in serum or BALF. Inflammatory cell counts in BALF and lung histology showed that leukocytosis and eosinophilia induced by OVA-sensitization/challenge were inhibited by the oral administration of BPUBE. Amelioration of eosinophil infiltration near the trachea was associated with reduced eotaxin and vascular cell adhesion molecule-1 (VCAM-1) levels. Changes in proinflammatory mediator levels in BALF suggest that BPUBE decreased OVA-sensitization-induced elevation of leukotriene C4 (LTC4) and prostaglandin D2 (PGD2). The finding that asthma-associated biomarker levels of OVA-sensitized/challenged mice were much more inhibited with BPUBE treatment than NPUBE (not-bioprocessed Ulmus parvifolia extract) treatment suggested the production of new bioactive compounds by the mushroom mycelia that may be involved in enhancing the observed antiasthmatic properties. The possible relation of the composition determined by proximate analysis and GC/MS to observed bioactivity is discussed. The results suggest that the elm tree (Ulmus parvifolia) bark bioprocessed with mycelia of shiitake (Lentinus edodes) mushrooms has the potential to prevent and/or treat allergic asthma.

Topics: Animals; Anti-Asthmatic Agents; Asthma; Female; Humans; Immunoglobulin E; Leukotriene C4; Mice; Mice, Inbred BALB C; Mycelium; Plant Bark; Plant Extracts; Shiitake Mushrooms; Th1 Cells; Th2 Cells; Ulmus; Vascular Cell Adhesion Molecule-1

Asthma is a frequent airway disease, and asthma control determinants have been associated with indoor allergen sensitization. The most frequent allergens are house dust mites (HDM), which act in vivo on the bronchial epithelial layer. Severe asthma has also been associated with bronchial remodeling and more specifically with increased mass of bronchial smooth muscle (BSM). However, the relationship between HDM stimulation of the bronchial epithelial layer and BSM remodeling is unknown.. To evaluate whether epithelial stimulation with HDM induces BSM cell proliferation in subjects with severe asthma.. A total of 22 subjects with severe asthma and 27 subjects with no asthma were recruited. We have developed an in vitro culture model combining an epithelium layer in air-liquid interface (ALI) interacting with BSM. We assessed BSM proliferation using BrdU incorporation. We explored the role of epithelium-derived mediators using reverse-transcriptase polymerase chain reaction (RT-PCR) and ELISA in vitro and in vivo. Finally, leukotrienes receptor expression was assessed in vitro by flow cytometry and RT-PCR and ex vivo by laser microdissection and RT-PCR.. We found that epithelial stimulation by HDM selectively increased the proliferation of asthmatic BSM cells and not that of nonasthmatic cells. The mechanism involved epithelial protease-activated receptor-2-dependent production of leukotrienes C4 associated with an overexpression of leukotrienes receptor CysLTR1 by asthmatic BSM cells in vitro and ex vivo.. This work demonstrates the selective role of HDM on BSM remodeling in patients with severe asthma and points out different therapeutic targets at epithelial and smooth muscle levels.

Topics: Adult; Aged; Animals; Asthma; Cell Culture Techniques; Cell Proliferation; Epithelium; Female; Humans; Leukotriene C4; Male; Mice, Inbred BALB C; Middle Aged; Pyroglyphidae; Receptors, Leukotriene; Reverse Transcriptase Polymerase Chain Reaction; Young Adult

Cysteinyl leukotrienes (cysLTs) are bronchoconstricting lipid mediators that amplify eosinophilic airway inflammation by incompletely understood mechanisms. We recently found that LTC4, the parent cysLT, potently activates platelets in vitro and induces airway eosinophilia in allergen-sensitized and -challenged mice by a platelet- and type 2 cysLT receptor-dependent pathway. We now demonstrate that this pathway requires production of thromboxane A2 and signaling through both hematopoietic and lung tissue-associated T prostanoid (TP) receptors. Intranasal administration of LTC4 to OVA-sensitized C57BL/6 mice markedly increased the numbers of eosinophils in the bronchoalveolar lavage fluid, while simultaneously decreasing the percentages of eosinophils in the blood by a TP receptor-dependent mechanism. LTC4 upregulated the expressions of ICAM-1 and VCAM-1 in an aspirin-sensitive and TP receptor-dependent manner. Both hematopoietic and nonhematopoietic TP receptors were essential for LTC4 to induce eosinophil recruitment. Thus, the autocrine and paracrine functions of thromboxane A2 act downstream of LTC4/type 2 cysLT receptor signaling on platelets to markedly amplify eosinophil recruitment through pulmonary vascular adhesion pathways. The findings suggest applications for TP receptor antagonists in cases of asthma with high levels of cysLT production.

Topics: Allergens; Animals; Aspirin; Asthma; Blood Platelets; Bone Marrow Transplantation; Bronchoalveolar Lavage Fluid; Cysteine; Eosinophilia; Inflammation; Intercellular Adhesion Molecule-1; Leukotriene Antagonists; Leukotriene C4; Leukotrienes; Lung; Mice; Mice, Inbred C57BL; Mice, Knockout; Ovalbumin; Platelet Activation; Receptors, Prostaglandin; Thromboxane A2; Vascular Cell Adhesion Molecule-1

Cysteinyl leukotrienes (LTs) are key mediators in inflammation. To explore the structure of the antigen-recognition site of a monoclonal antibody against LTC4 (mAbLTC), we previously isolated full-length cDNAs for heavy and light chains of the antibody and prepared a single-chain antibody comprising variable regions of these two chains (scFvLTC).. We examined whether mAbLTC and scFvLTC neutralized the biological activities of LTC4 and LTD4 by competing their binding to their receptors.. mAbLTC and scFvLTC inhibited their binding of LTC4 or LTD4 to CysLT1 receptor (CysLT1R) and CysLT2 receptor (CysLT2R) overexpressed in Chinese hamster ovary cells. The induction by LTD4 of monocyte chemoattractant protein-1 and interleukin-8 mRNAs in human monocytic leukemia THP-1 cells expressing CysLT1R was dose-dependently suppressed not only by mAbLTC but also by scFvLTC. LTC4- and LTD4-induced aggregation of mouse platelets expressing CysLT2R was dose-dependently suppressed by either mAbLTC or scFvLTC. Administration of mAbLTC reduced pulmonary eosinophil infiltration and goblet cell hyperplasia observed in a murine model of asthma. Furthermore, mAbLTC bound to CysLT2R antagonists but not to CysLT1R antagonists.. These results indicate that mAbLTC and scFvLTC neutralize the biological activities of LTs by competing their binding to CysLT1R and CysLT2R. Furthermore, the binding of cysteinyl LT receptor antagonists to mAbLTC suggests the structural resemblance of the LT-recognition site of the antibody to that of these receptors.. mAbLTC can be used in the treatment of inflammatory diseases such as asthma.

Topics: Animals; Antibodies, Monoclonal; Asthma; CHO Cells; Cricetinae; Cricetulus; Cytokines; Humans; Leukotriene Antagonists; Leukotriene C4; Leukotriene D4; Male; Mice; Mice, Inbred C57BL; Platelet Aggregation; Receptors, Leukotriene; Single-Chain Antibodies

The impact of air pollution on the respiratory system has been estimated on the basis of respiratory symptoms and lung function. However; few studies have compared lung inflammation in healthy and asthmatics children exposed to high levels of air pollution. The aim of the study was to elucidate the modulatory effect of air pollution on Cysteinyl-leukotrienes (Cys-LTs) levels in exhaled breath condensate (EBC) among healthy and asthmatic children.. We performed a cross-sectional comparative study. Children between 7-12 years of age, asthmatics and non-asthmatics, residents of a city with high levels of PM10 were included. In all cases, forced spirometry, Cys-LTs levels in EBC, and the International Study of Asthma and Allergies in Childhood questionnaire were evaluated. We also obtained average of PM10, CO, SO2 and O3 levels during the period of the study by the State Institute of Ecology.. We studied 103 children (51 asthmatics and 52 non-asthmatics). Cys-LTs levels were higher in asthmatics than in non-asthmatics (77.3 ± 21.6 versus 60.3 ± 26.8 pg/ml; p = 0.0005). Also, Cys-LTs levels in children with intermittent asthma were lower than in children with persistent asthma (60.4 ± 20.4 versus 84.7 ± 19.2 pg/ml; p = 0.0001). In the multiple regression model, factors associated with levels of Cys-LTs were passive smoking (β = 13.1, p 0.04) and to be asthmatic (β = 11.5, p 0.03).. Cys-LTs levels are higher in asthmatic children than in healthy children in a contaminated city and its levels are also associated with passive smoking.

Topics: Air Pollution; Asthma; Breath Tests; Child; Cross-Sectional Studies; Female; Forced Expiratory Volume; Healthy Volunteers; Humans; Inflammation Mediators; Leukotriene C4; Leukotriene D4; Leukotriene E4; Male; Particulate Matter; Pneumonia; Spirometry; Surveys and Questionnaires; Tobacco Smoke Pollution; Urban Population; Vital Capacity

Leukotrienes are potent inflammatory mediators which modulate immune responses and induce bronchoconstriction in susceptible individuals. Montelukast (MK) is a leukotriene receptor (CysLT1) antagonist that has been shown to prevent exacerbation of asthma. Considering the plethora of potential cellular targets for MK, specific mechanisms for its therapeutic action are still not fully understood. In vitro, we determined whether human dendritic cell function could be affected by leukotriene C(4) (LTC(4)) treatment and whether MK had potential in modulating this response. We also studied the effect of LTC(4) in the context of response to an airway virus (respiratory syncytial virus, RSV).. Human monocyte-derived dendritic cells (moDCs) exposed to LTC(4), MK, or both, were cocultured with autologous T cells, with or without RSV. The effects of LTC(4) and MK on cell function were determined by ELISA and proliferation assays.. Both moDCs and their precursors--monocytes--express LTC(4) receptor CysLT1, making them potential targets for MK. moDCs cultured with LTC(4) release the eosinophil chemoattractant RANTES (CCL5) and induce greater T cell proliferation. Both were blocked by the presence of MK. MK treatment, albeit anti-inflammatory, did not interfere with the moDC-dependent T cell-proliferative responses induced by RSV.. LTC(4), chronically present in the airways of asthma patients, could induce an exaggerated inflammatory response to airway infection via dendritic cell activation, which would be prevented by MK. Our study provides additional insight into the mechanisms of action of this leukotriene receptor antagonist.

Topics: Acetates; Anti-Asthmatic Agents; Asthma; Cell Proliferation; Chemokine CCL5; Coculture Techniques; Cyclopropanes; Dendritic Cells; Humans; Leukotriene C4; Primary Cell Culture; Quinolines; Receptors, Leukotriene; Respiratory Syncytial Viruses; Sulfides; T-Lymphocytes

Human blood eosinophils exhibit a hyperactive phenotype in response to chemotactic factors after cell "priming" with IL-5 family cytokines. Earlier work has identified ERK1/2 as molecular markers for IL-5 priming, and in this article, we show that IL-3, a member of the IL-5 family, also augments fMLP-stimulated ERK1/2 phosphorylation in primary eosinophils. Besides ERK1/2, we also observed an enhancement of chemotactic factor-induced Akt phosphorylation after IL-5 priming of human blood eosinophils. Administration of a peptide antagonist that targets the Src family member Lyn before cytokine (IL-5/IL-3) priming of blood eosinophils inhibited the synergistic increase of fMLP-induced activation of Ras, ERK1/2 and Akt, as well as the release of the proinflammatory factor leukotriene C(4). In this study, we also examined a human eosinophil-like cell line HL-60 clone-15 and observed that these cells exhibited significant surface expression of IL-3Rs and GM-CSFRs, as well as ERK1/2 phosphorylation in response to the addition of IL-5 family cytokines or the chemotactic factors fMLP, CCL5, and CCL11. Consistent with the surface profile of IL-5 family receptors, HL-60 clone-15 recapitulated the enhanced fMLP-induced ERK1/2 phosphorylation observed in primary blood eosinophils after priming with IL-3/GM-CSF, and small interfering RNA-mediated knockdown of Lyn expression completely abolished the synergistic effects of IL-3 priming on fMLP-induced ERK1/2 phosphorylation. Altogether, our data demonstrate a central role for Lyn in the mechanisms of IL-5 family priming and suggest that Lyn contributes to the upregulation of the Ras-ERK1/2 and PI3K-Akt cascades, as well as the increased leukotriene C(4) release observed in response to fMLP in "primed" eosinophils.

Topics: Adolescent; Adult; Amino Acid Sequence; Asthma; Eosinophils; HL-60 Cells; Humans; Interleukin-3; Interleukin-5; Leukotriene C4; Middle Aged; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Molecular Sequence Data; N-Formylmethionine Leucyl-Phenylalanine; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; ras Proteins; Signal Transduction; src-Family Kinases

Leukotriene (LT) C(4) and its metabolites, LTD(4) and LTE(4), are involved in the pathobiology of bronchial asthma. LTC(4) synthase is the nuclear membrane-embedded enzyme responsible for LTC(4) biosynthesis, catalyzing the conjugation of two substrates that have considerably different water solubility; that amphipathic LTA(4) as a derivative of arachidonic acid and a water-soluble glutathione (GSH). A previous crystal structure revealed important details of GSH binding and implied a GSH activating function for Arg-104. In addition, Arg-31 was also proposed to participate in the catalysis based on the putative LTA(4) binding model. In this study enzymatic assay with mutant enzymes demonstrates that Arg-104 is required for the binding and activation of GSH and that Arg-31 is needed for catalysis probably by activating the epoxide group of LTA(4).

Topics: Arginine; Asthma; Binding Sites; Crystallography, X-Ray; Glutathione; Glutathione Transferase; Humans; Leukotriene C4; Mutation; Protein Structure, Tertiary; Structure-Activity Relationship

To explore the characteristics of airway inflammatory cells, cytokines and inflammatory mediators in eosinophilic bronchitis (EB) and cough variant asthma (CVA) patients and to elucidate the underlying mechanism of distinct airway inflammation between EB and CVA.. This study included 15 patients with EB (EB group), 15 patients with cough variant asthma (CVA, CVA group), 14 patients with bronchial asthma (asthma group) and 14 healthy controls (healthy group). Percentage of eosinophils (EOS) in sputum induced by hypertonic saline was detected by FACS. The percentage of CD(69)(+) EOS stimulated by interleukin-5 (IL-5) and interferon γ (IFN-γ) was also detected by FACS. The expression of leukotriene C4 synthase (LTC4S) and prostaglandin-endoperoxide synthase-2 (PTGS2) mRNA in sputum was measured by real-time PCR and the concentration of leukotriene C4 (LTC4) and prostaglandin E2 (PGE2) in sputum was measured by ELISA.. The percentage of EOS in induced sputum was 15.8 ± 3.2 (EB group), 13.0 ± 2.7 (CVA group) and 11.6 ± 4.5 (asthma group), respectively, which were significantly higher than 1.0 ± 0.4 in the healthy group. The difference was significant and the t value was 16.31, 15.23 and 14.21 respectively (P < 0.05). After stimulated by IL-5 and IFN-γ, the percentage of CD(69)(+) EOS in induced sputum was 1.5 ± 0.4 and 1.5 ± 0.5 (EB group), 1.4 ± 0.4 and 1.4 ± 0.3 (CVA group) and 1.42 ± 0.72 and 1.37 ± 0.46 (asthma group) respectively. There was no statistical significance between these 3 groups, but when compared with 0.4 ± 0.2 and 0.4 ± 0.1 in healthy group, the difference was significant (P < 0.05). The expression of IL-5 mRNA and protein in induced sputum of EB group, CVA group and asthma group were higher than the healthy group and the difference was all statistically different (P < 0.05), but there was no statistical significance between EB group, CVA group and asthma group. The expression of IFN-γ mRNA and protein in induced sputum of each group was not different when compared with healthy group (P > 0.05). The concentration of PGE2 in induced sputum of EB group was(839 ± 69) ng/L, which was higher than (33 ± 8) ng/L of CVA group, (25 ± 6) ng/L of asthma group and (24 ± 8) ng/L of healthy group (all P < 0.01). There was no statistical difference between CVA group, asthma group and healthy group. The expression of PTGS2 in induced sputum of EB group increased significantly; when compared with CVA group, asthma group and healthy group, the difference was significant (all P < 0.01). The concentration of LTC4 in induced sputum of EB group, CVA group and asthma group was all higher than the healthy group (all P < 0.05). The expression of LTC4S mRNA of EB group, CVA group and asthma group was also higher than the healthy group (all P < 0.05). The expression of LTC4S mRNA and LTC4 in the EB group was higher than that in the CVA group and the asthma group (P < 0.05). The value of LTC4/PGE2 in the CVA group and the asthma group was higher than that in the EB group (t = 8.7 and 13.1, P < 0.05).. These data suggest that the difference in airway function observed in subjects with eosinophilic bronchitis and CVA (or asthma) may be due to the results of differences in PGE(2) production and an imbalance between the production of bronchoconstrictor LTC(4) and bronchoprotective PGE(2) lipid mediators.

Topics: Adult; Asthma; Bronchitis; Case-Control Studies; Cough; Dinoprostone; Eosinophilia; Female; Humans; Inflammation; Interleukin-5; Leukotriene C4; Male; Middle Aged; Sputum

Allergic asthma is a chronic and progressive inflammatory disease for which there is no satisfactory treatment. Studies reported tolerability and efficacy of an anti-asthma herbal medicine intervention (ASHMI) for asthma patients, developed from traditional Chinese medicine. To investigate the pharmacological actions of ASHMI on early- and late-phase airway responses (EAR and LAR), Ovalbumin (OVA)-sensitized mice received 6 weeks of ASHMI treatment beginning 24 h following the first intratracheal OVA challenge. EAR were determined 30 min following the fourth challenge and LAR 48 h following the last challenge. ASHMI effects on cytokine secretion, murine tracheal ring contraction and human bronchial smooth muscle cell prostaglandin (PG) production were also determined.ASHMI abolished EAR, which was associated with significantly reduced histamine, leukotriene C4, and OVA-specific IgE levels, as well as LAR, which was associated with significantly reduced bronchoalveolar lavage fluid (BALF) eosinophils, decreased airway remodeling, and lower Th2 cytokine levels in BALF and splenocyte cultures. Furthermore, ASHMI inhibited contraction of murine tracheal rings and increased production of the potent smooth muscle relaxer PGI(2). ASHMI abrogation of allergic airway responses is associated with broad effects on asthma pathological mechanisms.

Topics: Airway Remodeling; Animals; Anti-Asthmatic Agents; Asthma; Bronchoalveolar Lavage Fluid; Chromatography, High Pressure Liquid; Cytokines; Drugs, Chinese Herbal; Eosinophils; Histamine; Humans; Immunoglobulin E; In Vitro Techniques; Leukotriene C4; Lung; Mice; Mice, Inbred BALB C; Molecular Structure; Myocytes, Smooth Muscle; Ovalbumin; Prostaglandins; Trachea

To assess the efficacy of a combination of Boswellia serrata, licorice root (Glycyrrhiza glabra) and Tumeric root (Curcuma longa) as natural leukotriene inhibitor, antiinflammatory and antioxidant products respectively in controlling bronchial asthma.. The study comprised 63 patients with bronchial asthma that are further subdivided into two groups .Group 1 receiving oral capsule (combined herb) in a soft-gelatin capsule 3 times daily for 4weeks and group 2 receiving placebo. Plasma leukotriene C(4) (LTC(4))(,) nitric oxide (NO) and malondialdehyde (MDA) levels were measured and pulmonary function was also assessed in all patients enrolled in the study.. There was a statistically significant decrease in the plasma levels of LTC(4), (MDA), and NO in target therapy group when compared with placebo group.. The used extract contained Boswellia serrata, Curcuma longa and Glycyrrhiza has a pronounced effect in the management of bronchial asthma.

Topics: Adolescent; Adult; Anti-Inflammatory Agents; Asthma; Biological Products; Complementary Therapies; Curcuma; Drugs, Chinese Herbal; Glycyrrhiza; Humans; Inflammation Mediators; Leukotriene Antagonists; Leukotriene C4; Malondialdehyde; Middle Aged; Nitric Oxide; Plant Extracts; Plant Roots; Pulmonary Disease, Chronic Obstructive; Young Adult

The aerial part of Saururus chinensis has been used in folk medicine to treat several inflammatory diseases in China and Korea. Previously, our group reported that anti-asthmatic activity of an ethanol extract of Saururus chinensis (ESC) might occur, in part, via the inhibition of prostaglandin D(2) (PGD(2)) and leukotriene C(4) (LTC(4)) production, and degranulation reaction in vitro, as well as through the down-regulation of interleukin (IL)-4 and eotaxin mRNA expression in an in vivo ovalbumin-sensitization animal model. However, the effects of Saururus chinensis on eicosanoid generation, as well as Th2 cytokines and eotaxin production in an in vivo asthma model, have not been fully investigated. Moreover, it has not been determined whether ESC can ameliorate airway inflammation in vivo. In the present study, we investigated the therapeutic activity of Saururus chinensis on ovalbumin (OVA)-sensitized airway inflammation and its major phytochemical compositions.. Asthma was induced in BALB/c mice by ovalbumin-sensitization and inhalation. ESC (10-100 mg/kg) or dexamethasone (5 mg/kg), a positive control, was administered 7 times orally every 12 h from one day before the first challenge to 1 h before the second challenge. The recruitment of inflammatory cells and hyperplasia of goblet cells were evaluated by H&E and PAS staining. Levels of Th2 cytokines, eotaxin, PGD(2) and LTC(4) were measured to evaluate the anti-inflammatory activity of ESC in OVA-sensitized mice. Contents of major components were analyzed by HPLC using a reversed-phase C18 column.. ESC (10 mg/kg) suppressed allergic airway inflammation by inhibition of the production of IL-4 (P<0.001), IL-5 (P<0.05), IL-13 (P<0.001), eotaxin (P<0.001), PGE(2) (P<0.001), LTC(4) (P<0.001) in lung extract and IgE level (P<0.001) in the serum. In addition, ESC (50 mg/kg) reduced the infiltration of inflammatory cells and hyperplasia of goblet cells in the lung tissues. The anti-inflammatory effect of ESC was comparable to that of the positive control drug, dexamethasone. Its major phytochemical composition includes manassantin A, B and sauchinone.. These results suggest that ESC decreased inflammation and mucus secretion in the OVA-induced bronchial asthma model, and its anti-asthmatic activity may occur in part via the inhibition of Th2 cytokines and eotaxin protein expression, as well as through prostaglandin E(2) (PGE(2)) and leukotriene C(4) (LTC(4)) generation. This effects may be attributed particularly to the presence of manassantin A, B and sauchinone major component evidenced by a HPLC analysis.

Topics: Animals; Asthma; Chromatography, High Pressure Liquid; Cytokines; Dinoprostone; Disease Models, Animal; Ethanol; Female; Hyperplasia; Immunoglobulin E; Leukotriene C4; Lung; Medicine, Korean Traditional; Mice; Mice, Inbred BALB C; Ovalbumin; Plant Components, Aerial; Plant Extracts; Respiratory Mucosa; Saururaceae

It has been well-documented that leukotrienes (LTs) are released in allergic lung inflammation and that they participate in the physiopathology of asthma. A role for LTs in innate immunity has recently emerged: Cys-LTs were shown to enhance FcgammaR-mediated phagocytosis by alveolar macrophages (AMs). Thus, using a rat model of asthma, we evaluated FcgammaR-mediated phagocytosis and killing of Klebsiella pneumoniae by AMs. The effect of treatment with a cys-LT antagonist (montelukast) on macrophage function was also investigated. Male Wistar rats were immunized twice with OVA/alumen intraperitoneally and challenged with OVA aerosol. After 24 h, the animals were killed, and the AMs were obtained by bronchoalveolar lavage. Macrophages were cultured with IgG-opsonized red blood cells (50:1) or IgG-opsonized K. pneumoniae (30:1), and phagocytosis or killing was evaluated. Leukotriene C(4) and nitric oxide were quantified by the EIA and Griess methods, respectively. The results showed that AMs from sensitized and challenged rats presented a markedly increased phagocytic capacity via FcgammaR (10X compared to controls) and enhanced killing of K. pneumoniae (4X higher than controls). The increased phagocytosis was inhibited 15X and killing 3X by treatment of the rats with montelukast, as compared to the non-treated group. cys-LT addition increased phagocytosis in control AMs but had no effect on macrophages from allergic lungs. Montelukast reduced nitric oxide (39%) and LTC(4) (73%). These results suggest that LTs produced during allergic lung inflammation potentiate the capacity of AMs to phagocytose and kill K. pneumonia via FcgammaR.

Topics: Acetates; Allergens; Animals; Asthma; Cyclopropanes; Cysteine; Disease Models, Animal; Klebsiella pneumoniae; Leukotriene Antagonists; Leukotriene C4; Leukotrienes; Lung; Macrophages, Alveolar; Male; Nitric Oxide; Ovalbumin; Phagocytosis; Pneumonia; Quinolines; Rats; Rats, Wistar; Receptors, IgG; Sulfides

Increased levels of leukotrienes (LTs) in exhaled breath condensate (EBC) are associated with asthma and bronchial hyperresponsiveness (BHR), whereas eicosanoids generated through the 15-lipoxygenase (LO) pathway (15-hydroxyeicosatetraenoic acid [HETE] and eoxins) have been less studied.. We investigated whether metabolites of the 5- and 15-LO pathways in EBC are associated with childhood asthma, asthma severity, and clinical parameters.. The present study included 131 school-aged children (27 children with problematic severe asthma, 80 children with mild-to-moderate asthma, and 24 healthy children) from the Severe Asthma Recognized in Childhood study and 19 children with other nonasthmatic chronic lung diseases. Clinical work-up included spirometry, fractional exhaled nitric oxide measurements, skin prick testing, and methacholine challenge. Eicosanoids were analyzed in EBC by using mass spectrometry and are reported as concentrations (in picograms per milliliter) and eicosanoid/palmitic acid (PA) ratios.. Eoxin C₄/PA, eoxin D₄/PA, eoxin E₄/PA, 15-HETE/PA, and LTC₄/PA ratios were significantly increased in asthmatic versus healthy children. Eoxin D₄/PA and LTE₄/PA ratios were also significantly higher in children with BHR. A nonsignificant trend was observed toward higher eoxin/PA ratios with increasing asthma severity. In contrast to asthma, children with chronic lung disease had the highest 15-HETE/PA, LTC₄/PA, LTE₄/PA, and LTB₄/PA ratios.. The results point to increased activity of the 15-LO inflammatory pathway in childhood asthma. Mass spectrometric analyses of EBC demonstrate that increased eoxin levels not only accompany the increased 5-LO product LTC₄ but are also associated with BHR. These markers might represent a new therapeutic target for asthma treatment.

Topics: Adolescent; Arachidonate 15-Lipoxygenase; Asthma; Breath Tests; Bronchial Hyperreactivity; Child; Exhalation; Female; Humans; Hydroxyeicosatetraenoic Acids; Inflammation; Leukotriene C4; Leukotriene E4; Leukotrienes; Male; Mass Spectrometry; Severity of Illness Index

Secreted phospholipases A(2) (sPLA(2)s) are released in plasma and other biologic fluids of patients with inflammatory, autoimmune, and allergic diseases.. We sought to evaluate sPLA(2) activity in the bronchoalveolar lavage fluid (BALF) of asthmatic patients and to examine the expression and release of sPLA(2)s from primary human lung mast cells (HLMCs).. sPLA(2) activity was measured in BALF and supernatants of either unstimulated or anti-IgE-activated HLMCs as hydrolysis of oleic acid from radiolabeled Escherichia coli membranes. Expression of sPLA(2)s was examined by using RT-PCR. The release of cysteinyl leukotriene (LT) C(4) was measured by means of enzyme immunoassay.. Phospholipase A(2) (PLA(2)) activity was higher in the BALF of asthmatic patients than in the control group. BALF PLA(2) activity was blocked by the sPLA(2) inhibitors dithiothreitol and Me-Indoxam but not by the cytosolic PLA(2) inhibitor AZ-1. HLMCs spontaneously released a PLA(2) activity that was increased on stimulation with anti-IgE. This PLA(2) activity was blocked by dithiothreitol and Me-Indoxam but not by AZ-1. HLMCs constitutively express mRNA for group IB, IIA, IID, IIE, IIF, III, V, X, XIIA, and XIIB sPLA(2)s. Anti-IgE did not modify the expression of sPLA(2)s. The cell-impermeable inhibitor Me-Indoxam significantly reduced (up to 40%) the production of LTC(4) from anti-IgE-stimulated HLMCs.. sPLA(2) activity is increased in the airways of asthmatic patients. HLMCs express multiple sPLA(2)s and release 1 or more of them when activated by anti-IgE. The sPLA(2)s released by mast cells contribute to LTC(4) production by acting in an autocrine fashion. Mast cells can be a source of sPLA(2)s in the airways of asthmatic patients.

Topics: Antibodies, Anti-Idiotypic; Asthma; Aziridines; Bronchoalveolar Lavage Fluid; Carbamates; Cells, Cultured; Dithiothreitol; Humans; Immunoglobulin E; Indolizines; Leukotriene C4; Lung; Mast Cells; Naphthoquinones; Phospholipases A2, Secretory

Oral cysteinyl-leukotriene (LT) receptor antagonists such as montelukast are used for reducing airway inflammation and exacerbations. However, inhaled therapy using LT receptor antagonists has not been studied. In the present study, the effect of inhaled montelukast was investigated on airway hyperresponsiveness measured by cysteinyl-LT induced bronchoconstriction in an animal model of asthma. Bronchoconstriction responses were induced by inhaled LTC4 and LTD4 (0.2 microg/ml each) or three doses of intravenous LTC4 and LTD4 (0.3, 1, 3 microg/kg) in ovalbumin (OVA)-sensitized Hartley male guinea-pigs. The response was measured by the change in peak pressure of airway opening (Pao). The effect of montelukast was evaluated by the comparison of bronchoconstriction responses between the groups of animals pre-treated with 15-min inhalation of 10mg/ml montelukast and saline. To evaluate the tissue injury which might be caused by montelukast inhalation, lung tissues were examined for the histology. The broncoconstriction responses induced by inhaled LTC4 and LTD4 were enhanced by OVA sensitization in the guinea-pigs. In sensitized animals, the significant increases in peak Pao were 18.5+/-2.1 cmH(2)O by LTC4 inhalation and 25.0+/-1.6 cmH(2)O by LTD4 inhalation on average. Prior treatment of inhaled montelukast potently suppressed the peak Pao increases induced by both inhaled and intravenous LTC4 and LTD4 (all P<0.01 vs. saline control). Moreover, the suppression of inhaled montelukast against LTD4-induced bronchoconstriction was observed for at least up to 24h. According to the histological examination, montelukast inhalation produced no injury to the lung tissue. Inhaled montelukast, a cysteinyl-LT receptor antagonist, was effective in inhibiting cysteinyl-LT-induced acute bronchoconstriction, and may have the potential for clinical use as a new asthma drug.

Topics: Acetates; Administration, Inhalation; Animals; Asthma; Bronchial Hyperreactivity; Bronchoconstriction; Cyclopropanes; Cysteine; Disease Models, Animal; Guinea Pigs; Immunologic Factors; Leukotriene Antagonists; Leukotriene C4; Leukotriene D4; Leukotrienes; Lung; Male; Ovalbumin; Quinolines; Sulfides

Topics: Asthma; Cerebrovascular Disorders; Cysteine; Glutathione Transferase; Humans; Leukotriene C4; Leukotrienes; Polymorphism, Single Nucleotide; Stroke

Allergic asthma, an inflammatory disease characterized by the infiltration and activation of various leukocytes, the production of Th2 cytokines and leukotrienes, and atopy, also affects the function of other cell types, causing goblet cell hyperplasia/hypertrophy, increased mucus production/secretion, and airway hyperreactivity. Eosinophilic inflammation is a characteristic feature of human asthma, and recent evidence suggests that eosinophils also play a critical role in T cell trafficking in animal models of asthma. Nicotine is an anti-inflammatory, but the association between smoking and asthma is highly contentious and some report that smoking cessation increases the risk of asthma in ex-smokers. To ascertain the effects of nicotine on allergy/asthma, Brown Norway rats were treated with nicotine and sensitized and challenged with allergens. The results unequivocally show that, even after multiple allergen sensitizations, nicotine dramatically suppresses inflammatory/allergic parameters in the lung including the following: eosinophilic/lymphocytic emigration; mRNA and/or protein expression of the Th2 cytokines/chemokines IL-4, IL-5, IL-13, IL-25, and eotaxin; leukotriene C(4); and total as well as allergen-specific IgE. Although nicotine did not significantly affect hexosaminidase release, IgG, or methacholine-induced airway resistance, it significantly decreased mucus content in bronchoalveolar lavage; interestingly, however, despite the strong suppression of IL-4/IL-13, nicotine significantly increased the intraepithelial-stored mucosubstances and Muc5ac mRNA expression. These results suggest that nicotine modulates allergy/asthma primarily by suppressing eosinophil trafficking and suppressing Th2 cytokine/chemokine responses without reducing goblet cell metaplasia or mucous production and may explain the lower risk of allergic diseases in smokers. To our knowledge this is the first direct evidence that nicotine modulates allergic responses.

Topics: Allergens; Ambrosia; Animals; Asthma; Bronchoalveolar Lavage Fluid; Cytokines; Down-Regulation; Eosinophils; Female; Goblet Cells; Immunoglobulin E; Immunoglobulin G; Leukotriene C4; Lung; Mucin 5AC; Mucins; Muscle Cells; Nicotine; Rats; Rats, Inbred BN; Th2 Cells

Allergic airway diseases are more common in females than in males during early adulthood. A relationship between female hormones and asthma prevalence and severity has been suggested, but the cellular and molecular mechanisms are not understood.. To elucidate the mechanism(s) by which estrogens enhance the synthesis and release of mediators of acute hypersensitivity.. Two mast cell/basophil cell lines (RBL-2H3 and HMC-1) and primary cultures of bone marrow derived mast cells, all of which naturally express estrogen receptor-alpha, were examined. Cells were incubated with physiological concentrations of 17-beta-estradiol with and without IgE and allergens. Intracellular Ca(2+) concentrations and the release of beta-hexosaminidase and leukotriene C(4) were quantified.. Estradiol alone induced partial release of the preformed, granular protein beta-hexosaminidase from RBL-2H3, BMMC and HMC-1, but not from BMMC derived from estrogen receptor-alpha knock-out mice. The newly synthesized LTC(4) was also released from RBL-2H3. Estradiol also enhanced IgE-induced degranulation and potentiated LTC(4) production. Intracellular Ca(2+) concentration increased prior to and in parallel with mediator release. Estrogen receptor antagonists or Ca(2+) chelation inhibited these estrogenic effects.. Binding of physiological concentrations of estradiol to a membrane estrogen receptor-alpha initiates a rapid onset and progressive influx of extracellular Ca(2+), which supports the synthesis and release of allergic mediators. Estradiol also enhances IgE-dependent mast cell activation, resulting in a shift of the allergen dose response.

Topics: Allergens; Animals; Asthma; beta-N-Acetylhexosaminidases; Calcium Signaling; Cell Line; Estradiol; Estrogen Receptor alpha; Female; Humans; Immunoglobulin E; Leukotriene C4; Male; Mast Cells; Mice; Mice, Knockout; Rats; Sex Characteristics

Airway remodeling has recently emerged as a major problem in an increasing percentage of patients with asthma. Reasons for great diversity in the progression of irreversible bronchoconstriction among asthmatics remain unclear.. The aim of this study was to assess whether the potential ability of leukocytes to produce cysteinyl leukotrienes in response to various stimuli is correlated with magnitude of irreversible airway obstruction in asthmatics.. The study sample comprised 76 asthmatics (34 males, mean +/- SD age 52 +/- 13 years), and 35 healthy controls (18 males, 38.2 +/- 15 years). Each subject underwent 2 pulmonary function tests: before and after bronchodilator administration. In addition, approximate annual decline in forced expiratory volume in 1 second (FEV1) (% of predicted) was calculated. Leukotriene C4 (LTC4) production was assessed combining a cellular antigen stimulation test and enzyme-linked immunosorbent assay using Bulhmann Laboratories AG kits. Leukocytes isolated from peripheral blood were stimulated with anti-FcepsilonRI antibody, N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA). In separate tubes each subject's leukocytes were tested for spontaneous LTC4 production. Finally, stimulated LTC4 production was expressed in pg/mL after subtraction of values of spontaneous production.. In asthmatics, baseline FVC% and FEV% values ranged from 24.4% to 122.4% (mean, 75.5%) and from 23.4% to 126.6% (mean, 74.4%), respectively. There were no significant differences between asthmatics and controls in LTC4 production stimulated by anti-FcepsilonRI antibody (P = .79), fMLP (P = .33) or PMA (P = .86). We found no correlation between stimulated LTC4 production and spirometric parameters at baseline or after bronchodilator administration or annual decline in FEV1%.. Our results do not confirm the hypothesis that airway remodeling in asthma might be related to enhanced ability of leukocytes to produce cysteinyl leukotrienes in response to various stimuli.

Topics: Adult; Airway Obstruction; Antibodies; Asthma; Cells, Cultured; Humans; Leukocytes; Leukotriene C4; Male; Middle Aged; N-Formylmethionine Leucyl-Phenylalanine; Receptors, IgE; Spirometry; Tetradecanoylphorbol Acetate

To explore the regularity of recipe composition by observing inhibitory effects on the genic expression of 5-lipoxygenase activating protein, IL-4 and the leukotriene C4 in asthmatic mice.. The mice were challenged with OVA and administered ig with the Herba Ephedrae decoction (HED), separated compositions (2500 mg x kg(-1), calculated by Herba Ephedrae) and dexamethasone (2 mg x kg(-1)) respectively once daily for seven days. The real-time fluorescence quantitative PCR method was employed to measure the contents of FLAP mRNA and IL-4 mRNA expressions in lung and the ELISA method was used to determine the content of LTC4 in the washing solution of pulmonary alveolus and bronchi.. In the lung of asthma mice, the expressions of FLAP and IL-4 and the content of LTC4 were significantly augmented compared with the control group. The HED and the separated compositions could suppress the expressions of FLAP and IL-4 and LTC4 release to a great extent in mice.. The HED had the remarkable effects of antianaphylaxis asthma and the original formula HED worked best. These results confirmed the rationality and scientific level of HED.

Topics: 5-Lipoxygenase-Activating Proteins; Animals; Asthma; Bronchoalveolar Lavage Fluid; Carrier Proteins; Drugs, Chinese Herbal; Enzyme-Linked Immunosorbent Assay; Ephedra sinica; Interleukin-4; Leukotriene C4; Lung; Male; Membrane Proteins; Mice; Ovalbumin; Plants, Medicinal; Random Allocation; RNA, Messenger

During an asthmatic episode, leukotriene C4 (LTC4) and interleukin 13 (IL-13) are released into the airways and are thought to be central mediators of the asthmatic response. However, little is known about how these molecules interact or affect each other's signaling pathway.. To determine if the LTC4 and IL-13 signaling pathways interact with each other's pathways.. We examined airway responsiveness, cysteinyl LTs (Cys-LTs), and Cys-LT and IL-13 receptor transcript levels in wild-type mice and in mice that were deficient in gamma-glutamyl leukotrienase (an enzyme that converts LTC4 to LTD4), STAT6 (signal transducer and activator of transcription 6 [a critical molecule in IL-13 signaling]), and IL-4Ralpha (a subunit of the IL-13 receptor).. Wild-type (C57BL/129SvEv) and gamma-glutamyl leukotrienase-deficient mice showed increased airway responsiveness after intranasal instillation of IL-13; similar results were observed after intranasal instillation of IL-13 or LTC4 in a second wild-type strain (BALB/c). Interleukin 13 treatment reduced levels of Cys-LTs in bronchoalveolar lavage fluid. This change was unaccompanied by changes in other arachidonic acid metabolites or in RNA transcript levels of enzymes associated with Cys-LT synthesis. Interleukin 13 treatment also increased transcript levels of the Cys-LT 1 and Cys-LT 2 receptors, while LTC4 increased transcript levels of the alpha1 chain of the IL-13 receptor. Furthermore, IL-4Ralpha-deficient mice had increased airway responsiveness to LTC4 but not to IL-13, whereas STAT6-deficient mice failed to respond to either agonist.. These findings indicate that LTC4 and IL-13 are dependent on or signal through STAT6 to increase airway responsiveness and that both agonists regulate expression of each other's receptors.

Topics: Airway Resistance; Animals; Asthma; Bronchoalveolar Lavage Fluid; Dipeptidases; Disease Models, Animal; Humans; Interleukin-13; Interleukin-13 Receptor alpha1 Subunit; Leukotriene C4; Membrane Proteins; Mice; Mice, Inbred C57BL; Mice, Transgenic; Receptors, Interleukin; Receptors, Interleukin-13; Receptors, Interleukin-4; Receptors, Leukotriene; Recombinant Proteins; RNA, Messenger; Signal Transduction; STAT6 Transcription Factor

Histamine, leukotriene C4, IL-4, and IL-13 are major mediators of allergy and asthma. They are all formed by basophils and are released in particularly large quantities after stimulation with IL-3. Here we show that supernatants of activated mast cells or IL-3 qualitatively change the makeup of granules of human basophils by inducing de novo synthesis of granzyme B (GzmB), without induction of other granule proteins expressed by cytotoxic lymphocytes (granzyme A, perforin). This bioactivity of IL-3 is not shared by other cytokines known to regulate the function of basophils or lymphocytes. The IL-3 effect is restricted to basophil granulocytes as no constitutive or inducible expression of GzmB is detected in eosinophils or neutrophils. GzmB is induced within 6 to 24 hours, sorted into the granule compartment, and released by exocytosis upon IgE-dependent and -independent activation. In vitro, there is a close parallelism between GzmB, IL-13, and leukotriene C4 production. In vivo, granzyme B, but not the lymphoid granule marker granzyme A, is released 18 hours after allergen challenge of asthmatic patients in strong correlation with interleukin-13. Our study demonstrates an unexpected plasticity of the granule composition of mature basophils and suggests a role of granzyme B as a novel mediator of allergic diseases.

Topics: Antibodies, Monoclonal; Asthma; Basophils; Bronchoalveolar Lavage; Complement C5a; Granzymes; Humans; Inflammation; Interleukin-13; Interleukin-3; Killer Cells, Natural; Leukotriene C4; Mast Cells; Serine Endopeptidases; T-Lymphocytes, Cytotoxic

To observe the changing contents of leukotriene B4 ( LTB4 ), leukotriene C4 ( LTC4 ), and leukotriene D4 (LTD4 ) of lung tissue in asthmatic rats, and explore the effect of Shuanglong Capsule (SLC) on it.. SD rats were randomly divided into the nomal group, asthmatic model group, Dexamethasone group and the high, middle and low dose SLC groups. All rats except those in the normal group were sensitized by ovalbumin and challenged with the antigen, and the contents of LTB4, LTC4 and LTD4 in lung tissue of all the groups were measured by reverse phase-high performance liquid chromatography (RP-HPLC) and compared.. The levels of LTB4, LTC4, and LTD4 of asthmatic rats were significantly higher than those of rats in the normal group. Dexamethasone and SLC at the dose of 8. 27 g/kg or 4. 13 g/kg could significantly inhibit the production of leukotrienes of lung tissue in asthmatic rats (P <0.05).. SLC can significantly inhibit the formation of inflammatory medium LTs of lung tissue in asthmatic rats, it may be one of the key mechanisms of SLC in anti-asthma and anti-inflammatory action.

Topics: Animals; Anti-Asthmatic Agents; Asthma; Drugs, Chinese Herbal; Leukotriene B4; Leukotriene C4; Leukotriene D4; Leukotrienes; Lung; Rats; Rats, Sprague-Dawley; Tablets

Smoking is the most important cause of chronic obstructive pulmonary disease (COPD). However, the influence of cigarette smoking on the pathogenesis of asthma in the elderly remains controversial. This study attempted to clarify the influence of cigarette smoking on elderly asthmatics.. Forty-eight asthmatics over 70 years old (25 ex-smokers and 23 never-smokers) and 20 patients with COPD over 70 years old (all ex-smokers) were studied to determine the influence of cigarette smoking on IgE-mediated allergy (total IgE, IgE antibodies against inhalant allergens, bronchial hyper-responsiveness (BHR), generation of leukotriene (LT) B4 and C4), pulmonary function, and the relative area of lung showing attenuation values less than -950 Hounsfield units (RA950) on high-resolution computed tomography scans.. The incidence of positive IgE antibodies against inhalant allergens, BHR, and the generation of leukotriene B4 (LTB4) by leucocytes were significantly increased in patients with a history of smoking compared with those without. Residual volume (%RV) was significantly increased, and diffusing capacity for carbon monoxide was significantly decreased in ex-smokers with asthma and COPD compared with never-smokers with asthma. Inspiratory RA950 and ratio of expiratory RA950 to inspiratory RA950 were significantly larger in asthmatics with a smoking history than in those without, and in COPD patients than in asthmatics.. Cigarette smoking enhances the production of IgE antibodies, BHR, and generation of LTB4 by leucocytes in elderly asthmatics. Increased hyper-inflation or emphysematous changes of the lungs expressed by increased RA950, closely related to %RV, was more frequently observed in ex-smokers compared with never-smokers.

Topics: Aged; Asthma; Bronchial Hyperreactivity; Case-Control Studies; Chi-Square Distribution; Female; Humans; Immunoglobulin E; Leukocytes; Leukotriene B4; Leukotriene C4; Male; Pulmonary Diffusing Capacity; Pulmonary Disease, Chronic Obstructive; Respiratory Function Tests; Smoking; Tomography, X-Ray Computed

5-Lipoxygenase is the key enzyme in the biosynthesis of leukotrienes, powerful lipid mediators involved in inflammation, cell-cell communication, and other important physiological and pathological conditions. Particularly, cysteinyl-leukotrienes have been recognized as playing a significant role in the pathophysiology of asthma and potent and effective Cys-LT1 receptor antagonists have been developed for the treatment of this illness. Here we report that montelukast, a structural Cys-LT1 receptor antagonist, also exerts a substantial and apparently direct inhibitory effect on 5-lipoxygenase activity in vitro, at concentrations in the lower micromolar range, which are of potential therapeutic relevance. Thus, when human mast cells HMC-1 were stimulated with the Ca ionophore A23187 in the presence of montelukast (up to 100 microM) a substantial decline in 5-lipoxygenase biosynthesis was observed. Similar results were obtained in the rat mast cell-like RBL-1 cell model (IC50 congruent with 2.5 microM) and in human polymorphonuclear leukocytes. Moreover, montelukast directly inhibited human recombinant 5-lipoxygenase. Kinetic experiments revealed that the inhibition was of the non-competitive type, suggesting that montelukast binds a yet undefined allosteric site on 5-lipoxygenase. 5-Lipoxygenase inhibition by montelukast appears to be highly selective since the drug had no effects on other enzymes of the leukotriene cascade, viz. LTC4 synthase and LTA hydrolase.

Topics: Acetates; Allosteric Site; Animals; Anti-Asthmatic Agents; Asthma; Calcimycin; Calcium; Catalysis; Cell Line; Cell Line, Tumor; Cell Survival; Cells, Cultured; Chromatography, High Pressure Liquid; Cyclopropanes; Dexamethasone; Dose-Response Relationship, Drug; HL-60 Cells; Humans; Inhibitory Concentration 50; Kinetics; Leukotriene B4; Leukotriene C4; Lipoxygenase Inhibitors; Mast Cells; Neutrophils; Protein Binding; Quinolines; Rats; Recombinant Proteins; Sulfides

Topics: Arachidonate 5-Lipoxygenase; Asthma; Eosinophils; Gene Frequency; Genotype; Humans; Leukotriene C4; Promoter Regions, Genetic

Migration from blood to tissue modulates eosinophil function, possibly through interactions with endothelial cells. The effects of contact with and migration through endothelial cells on eosinophil expression of surface markers and release of leukotriene C4 were evaluated. A small proportion (2.6%) of eosinophils spontaneously migrated through endothelial cell monolayers. Activation of endothelial cells by interleukin (IL)-4 or IL-1beta slightly increased this migration (to 12.4%), which became much greater when a chemoattractant was placed in the lower chamber (84.3%). However, the chemotactic effect was downregulated by pretreating endothelial cells with interferon gamma (IFN-gamma; 63.1%). At baseline, 5% of eosinophils expressed CD69; this increased to 30.7% in culture on untreated endothelial cells and to 50.9% on IL-1beta-pretreated endothelial cells. This effect was mediated through intercellular adhesion molecule-1/CD11b interaction. Eosinophil migration through endothelial cells further increased CD69 expression to 63.9% and also increased CD35 expression from 83.3 to 91.3%. Upon stimulation, eosinophils that had migrated through endothelial cells produced more leukotriene C4 than control cells (872.4 and 103.9 pg x mL(-1), respectively). Endothelial cell pretreatment with IL-4 or IL-1beta further increased leukotriene C4 release (1,789.1 and 2,895.1 pg x mL(-1), respectively), whereas pretreatment with IFN-gamma decreased it (293.7 pg x mL(-1)). These data show that in vitro interactions with endothelial cells upregulate eosinophil membrane receptor expression and mediator release and that these effects are differently modulated by T-helper cell type 1 and 2 cytokines. These eosinophil modulations may play an important role in asthma pathogenesis.

Topics: Adjuvants, Immunologic; Adolescent; Adult; Antigens, CD; Antigens, Differentiation, T-Lymphocyte; Antigens, Surface; Asthma; Cell Movement; Endothelium, Vascular; Eosinophils; Female; Humans; In Vitro Techniques; Interleukin-1; Interleukin-4; Lectins, C-Type; Leukotriene C4; Lymphokines; Male; Middle Aged; Receptors, Complement 3b; T-Lymphocytes, Helper-Inducer

Airway dehydration and subsequent hyperosmolarity of periciliary fluid are considered critical events in exercise-induced bronchoconstriction (EIB). It has been shown that an in vitro hyperosmolar stimulation of basophils and mast cells with mannitol can induce the release of histamine and leukotrienes. The aim of this study was to establish if a hyperosmolar challenge could trigger activation of eosinophils to release chemokines and lipid mediators. Peripheral blood eosinophils were isolated from seven asthmatic and six non-asthmatic subjects. Hyperosmolar stimulation of eosinophils with mannitol (0.7 M), resulted in a significant increase in LTC4 levels compared to baseline in both asthmatic (15.2+/-4.6 vs. 70.1+/-9.5; P = 0.0002) and control subjects (14.3+/-4.0 vs. 55.6+/-5.6; P = 0.0001). ECP levels did not increase significantly above baseline following mannitol stimulation in either group. This study shows that eosinophils can be activated by a hyperosmolar stimulus. Therefore it seems reasonable to suggest that eosinophils could contribute to EIB.

Topics: Adolescent; Adult; Aged; Asthma; Blood Proteins; Bronchoconstriction; Diuretics, Osmotic; Enzyme-Linked Immunosorbent Assay; Eosinophil Granule Proteins; Eosinophils; Exercise; Female; Humans; Inflammation Mediators; Leukotriene C4; Male; Mannitol; Middle Aged; Osmolar Concentration; Ribonucleases

Although the mechanisms of aspirin-induced rhinosinusitis-asthma appear to be related to arachidonic acid abnormalities, only recently has a specific aspirin-triggered enhancement of 15-hydroxyeicosatetraenoic acid (15-HETE) generation in nasal polyp epithelial cells from aspirin-sensitive patients been demonstrated.. The aim of this study was to assess generation of 15-HETE and other eicosanoids by peripheral blood leukocytes (PBLs) from aspirin-sensitive and aspirin-tolerant asthmatic patients and modulation of 15-HETE generation by a prostaglandin (PG) E(1) analogue (misoprostol).. Twenty-four aspirin-sensitive patients with asthma-rhinosinusitis and 18 aspirin-tolerant asthmatic patients were studied, and eicosanoids released from PBLs were assessed by means of enzyme immunoassays.. Unstimulated PBLs from aspirin-sensitive and aspirin-tolerant patients generated similar amounts of PGE(2), leukotriene C(4), and 15-HETE, but lipoxin A(4) release was significantly less in aspirin-sensitive patients (300 +/- 70 pg/mL) in comparison with that seen in aspirin-tolerant patients (690 +/- 100 pg/mL, P <.05). Cell incubation with 2, 20, or 200 micromol/L aspirin resulted in a dose-dependent increase in 15-HETE generation (mean change of +85%, +189%, and +284% at each aspirin concentration, respectively) only in aspirin-sensitive asthmatic patients. Naproxen stimulated 15-HETE generation in aspirin-sensitive asthmatic patients, but indomethacin or specific COX-2 inhibitors (NS-398 and celecoxib) did not affect 15-HETE release. A synthetic PGE(1) analogue (misoprostol) inhibited aspirin-induced 15-HETE release but enhanced 15-HETE generation by aspirin in leukocytes from aspirin-tolerant patients. After preincubation with misoprostol, aspirin induced a dose-dependent production of lipoxin A(4) in both groups.. PBLs from patients with aspirin-sensitive rhinosinusitis-asthma might be specifically triggered by aspirin to generate 15-HETE. Metabolism of 15-HETE is differentially regulated by misoprostol in aspirin-tolerant and aspirin-sensitive asthmatic patients.

Topics: Adult; Aged; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Asthma; Dinoprostone; Drug Tolerance; Eicosanoids; Female; Humans; Hydroxyeicosatetraenoic Acids; In Vitro Techniques; Ionophores; Leukocytes; Leukotriene C4; Lipoxins; Male; Middle Aged; Misoprostol

To explore the changes of leukotrienes (LT) in cerebral cortex and lung tissues in ovalbumin-induced rat asthma model and effects of different anti-asthma drugs on the changes.. Aerosol antigen-induced changes of inflammation in bronchoalveolar lavage fluids (BALF), pulmonary and brain histologic section in sensitized rats were investigated. Changes of LTB4 and LTC4 in lung and cerebral cortex homogenates were analyzed by reverse-phase high performance liquid chromatography (RP-HPLC).. The number of inflammatory cells in BALF and the score of lung and brain histological examination from antigen- challenged rats were significantly higher than that from control group (P<0.05). Dexamethason (DXM, 0.5 mg/kg, ip) and ketotifen fumarate (KF, 5 mg/kg, ig) markedly reduced total leukocyte number in BALF, and inhibited eosinophil accumulation, reduced the infiltration of eosinophils, and improved mucous edema and epithelial lesion of bronchi and bronchioles. In addition, RP-HPLC results shown LTB4 in lung and cerebral cortex homogenates were increased in antigen-challenged rats [(4.1+/-2.4) ng/g and (1.5+/-0.9) ng/g, respectively] compared with control group [(1.55+/-0.21) ng/g and (0.7+/-0.3) ng/g, respectively, P<0.05], both DXM (0.5 mg/kg, ip) and KF (5 mg/kg, ig) reduced LTB4 amount in lung[(1.4+/-0.6) ng/g and (1.8+/-0.7) ng/g] and cerebral cortex homogenates [(0.5+/-0.4) ng/g and (0.7+/-0.4) ng/g] in asthma rats. LTC4 content in lung homogenates in asthma rats was increased compared with control group [(1.9+/-0.9) ng/g and (0.5+/-0.3) ng/g, respectively] (P<0.05), but it has no change in cerebral cortex homogenates. DXM (0.5 mg/kg, ip) and KF (5 mg/kg, ig) reduced LTC4 amount in lung homogenates in asthma rats [(0.8+/-0.6) ng/g and (1.0+/-0.3) ng/g, respectively] (P<0.05).. The results indicate there is coincidental increase of LTB4 between central nervous system and lung tissues in asthma rats. DXM and KF can inhibit the change.

Topics: Animals; Anti-Inflammatory Agents; Asthma; Cerebral Cortex; Dexamethasone; Female; Histamine H1 Antagonists; Ketotifen; Leukotriene B4; Leukotriene C4; Lung; Male; Ovalbumin; Rats; Rats, Sprague-Dawley

The association between asthma and sinusitis has long been recognized. Numerous studies point to a complex, yet undeniable relationship between asthma and chronic sinusitis and rhinitis. There have also been extensive attempts to characterize the inflammatory mechanisms of both disorders. Increasingly, the cysteinyl leukotrienes, a potent group of inflammatory mediators, have gained attention as important contributors to the manifestation of both disorders. Leukotriene production has been shown to be upregulated in the bronchial tissue of asthmatics. Our study sought to determine if leukotriene production was increased in the sinus mucosa of asthmatics with chronic sinusitis.. Prospective study.. Nasal polyp tissue was evaluated from 27 consecutive patients undergoing elective polypectomy. The presence of asthma was determined by patient history, their medical record, and use of asthma medication. Sinus tissue was extracted during the course of endoscopic surgery. Cysteinyl leukotrienes (CysLT) were quantified by a sensitive competitive enzyme immunoassay, and the levels of CysLT were compared in the group with and without asthma.. Cysteinyl leukotrienes were detected in 23 of 27 patients. The average level of LTC4 in non-asthmatic patients was 25.6 picograms (pg)/g. The average amount of LTC4 in asthmatic patients with sinusitis was 19.2 pg/g. There was no significant difference between the two groups (P =.64).. The presence of asthma does not correlate with increased levels of leukotrienes in the sinus mucosa of patients with chronic sinusitis.

Topics: Asthma; Chronic Disease; Female; Humans; Leukotriene C4; Male; Prospective Studies; Sinusitis

Airway hyperresponsiveness (AHR) is one of the characteristic features of human asthma. The presence of AHR and the precise mechanisms immediately after establishment of sensitization in guinea pigs are unclear, although there are many reports showing allergen exposure that causes an increase in bronchial responsiveness associated with eosinophil influx into the airway in sensitized guinea pigs.. We investigated the inhibitory effects on AHR to histamine of ONO-1078, a leukotriene antagonist; indomethacin, a cyclooxygenase inhibitor; S-145, a thromboxane A(2) (TXA(2)) antagonist, and Y-24180, a platelet-activating factor (PAF) antagonist, to assess the involvement of chemical mediators in AHR employing ovalbumin (OA) sensitized guinea pig models.. Male Hartley guinea pigs were used. Each group comprised 4-7 animals. The animals were sensitized to OA, injecting intraperitoneally 30 mg of cyclophosphamide and 2,000 microg of OA together with 100 mg of aluminum hydroxide as the adjuvant. The guinea pigs were artificially ventilated via a cannula using a small-animal respirator after intraperitoneal anesthesia with pentobarbital sodium for tracheotomy. The pressure at the airway opening (PAO) was measured using a differential pressure transducer, and a differential pressure of peak PAO (peak DeltaPAO) at inspiratory phase as an overall index of bronchial response to bronchoactive agents was used. While being artificially ventilated, the animals were exposed to physiological saline solution containing various concentrations of histamine (4.9, 9.8, 20, 39, 78, and 156 microg/ml) by inhalation for 30 s at 3-min intervals. Determinations were made at 1 min after each inhalation. The chemical mediators were each (30 mg/kg of ONO-1078, 3 mg/kg of S-1452, and 1 mg/kg of Y-24180) administered orally to sensitized guinea pigs, and the airway response to histamine was assessed. Each group comprised 4-7 animals.. The airway response to histamine was significantly greater in the sensitized group than in the nonsensitized group at histamine concentrations of 36 (p < 0.05), 78, and 156 mg/ml (p < 0.01). Leukotrienes C(4) and D(4): 30 mg/kg of ONO-178 did not show any inhibitory effect on airway response to inhaled histamine. Cyclooxygenase: 5 mg/kg of indomethacin did not show any inhibitory effect on the airway response to inhaled histamine. TXA(2): the AHR to inhaled histamine at doses of 9.8, 39, 78, and 156 microg/ml was significantly inhibited by prior administration of 3 mg/kg of S-1452. PAF: the AHR to inhaled histamine at doses of 9.8, 39, and 78 microg/ml was significantly inhibited by prior administration of 1 mg/kg of Y-24180.. S-1452 (3 mg/kg) and Y-24180 (1 mg/kg) significantly inhibited AHR to histamine, while ONO-108 (30 mg/kg) and indomethacin (5 mg/kg) did not. The results suggest that TXA(2) and PAF are involved in AHR in OA-sensitized guinea pigs.

Topics: Airway Resistance; Animals; Asthma; Bronchial Hyperreactivity; Disease Models, Animal; Dose-Response Relationship, Drug; Guinea Pigs; Histamine; Indomethacin; Leukotriene C4; Leukotriene D4; Male; Ovalbumin; Platelet Activating Factor; Probability; Reference Values; Sensitivity and Specificity; Thromboxane A2

We have used the relatively noninvasive technique of induced sputum to measure allergen-induced changes in the concentration of eicosanoid mediators in bronchial secretions from atopic asthmatics. Sputum induction was performed before and 24 h after inhalational allergen challenge in 14 atopic asthmatics who developed a late asthmatic reaction (LAR). Differential cell counts were made on sputum cytospins and eicosanoid (cysteinyl leukotrienes [cys LTs], prostaglandin D(2) [PGD(2)], and PGE(2)) concentrations were measured in the sputum supernatants. The percentage of eosinophils at baseline correlated with the concentration of cys LTs (r = 0.84, p < 0.001) but not prostanoid mediators. Allergen challenge produced a significant increase in the concentration of sputum cys LTs from 3. 45 ng/ml sputum to 11.95 ng/ml (p = 0.002), which correlated with the increase in sputum eosinophils (r = 0.55, p < 0.05). There were no significant changes in PGD(2) or PGE(2) concentrations in sputum supernatants in response to challenge. Thus, the noninvasive technique of induced sputum has been used to demonstrate increased cys LTs, but not prostanoids associated with LAR after allergen challenge. The correlation between eosinophil numbers and cys LT concentrations at baseline values and 24 h after allergen challenge is consistent with these cells being a principal source of cys LTs within the airways at these time points.

Topics: Adult; Allergens; Asthma; Bronchial Provocation Tests; Cell Count; Dinoprostone; Female; Humans; Hypersensitivity, Immediate; Leukotriene C4; Leukotriene D4; Leukotriene E4; Leukotrienes; Male; Middle Aged; Prostaglandin D2; Sputum

We studied the effect of contact with bronchial epithelial cells on the functional activity of human eosinophils, measured as the production of a bronchoconstrictor lipid mediator, leukotriene C4 (LTC4) to determine the role of cell-cell interaction in activation of airway eosinophils.. Eosinophils were isolated from peripheral blood of atopic donors. Epithelial cells were obtained from the bronchi of surgically resected lung lobes and cultured to confluence on collagen-coated plates. Eosinophils were stimulated with platelet activating factor (PAF) or serum opsonized zymosan (SOZ) after incubation with or without epithelial cells. Leukotriene C4 (LTC4) was assayed in supernatants by enzyme immunoassay.. Bronchial epithelial cells did not produce LTC4 in response to PAF or SOZ. Eosinophils pre-incubated in collagen-coated plates for 1 h produced LTC4 in response to both PAF (130 +/- 53 fmol/10(6) eosinophils at 10 micromol/l PAF, 5 min) and SOZ (1,900 +/- 550 fmol/10(6) eosinophils at 2 mg/ml SOZ, 15 min). Eosinophils co-incubated with bronchial epithelial cells for 1 h produced significantly higher quantities of LTC4 in response to both PAF (310 +/- 94 fmol/10(6) eosinophils; P<0.01) and SOZ (5,500 +/- 1,500 fmol/10(6) eosinophils; P<0.001). Ligation of the common beta2 integrin subunit (CD18) with a monoclonal antibody inhibited PAF-stimulated and augmented SOZ-stimulated LTC4 generation by eosinophils alone but had marginal effects on the epithelium-dependent up-regulation.. Contact with bronchial epithelial cells up-regulates the responsiveness of human eosinophils, a finding that has significant implications in the pathology of asthma.

Topics: Asthma; Bronchi; CD18 Antigens; Cells, Cultured; Coculture Techniques; Eosinophils; Epithelial Cells; Humans; Integrin beta1; Integrins; Leukotriene C4; Stimulation, Chemical; Up-Regulation; Zymosan

Asthma is characterized by chronic airway inflammation resulting from overproduction of pro-inflammatory mediators, such as leukotrienes (LT). The authors questioned the biosynthetic capacity of asthmatic patients for lipoxins (LX) and 15-epimer lipoxins (15-epi-LX), endogenous regulators of inflammatory responses that inhibit pro-inflammatory events. Levels of LXA4, 15-epi-LXA4 and LTC4 were determined in 14 clinically characterized aspirin-intolerant asthmatics (AIA), 11 aspirin-tolerant asthmatics (ATA) and eight healthy volunteers using a stimulated whole blood protocol. Both LXA4 and 15-epi-LXA4 were generated in whole blood activated by the divalent cation ionophore, A23187. Higher levels of LXA4 were produced in ATA than either AIA or healthy volunteers. Exposure of AIA whole blood to interleukin-3 prior to A23187 did not elevate their reduced capacity to generate LXA4. Generation of a bronchoconstrictor, LTC4, was similar in both AIA and ATA. Consequently, the ratio of LXA4:LTC4 quantitatively favoured the bronchoconstrictor for AIA and differed from both ATA and healthy subjects. In addition, the capacity for 15-epi-LXA4 generation was also diminished in AIA, since whole blood stimulated in the presence of aspirin gave increased levels only in samples from ATA. The present results indicate that asthmatics possess the capacity to generate both lipoxins and 15-epimer-lipoxins, but aspirin-intolerant asthmatics display a lower biosynthetic capacity than aspirin-tolerant asthmatics for these potentially protective lipid mediators. This previously unappreciated, diminished capacity for lipoxin formation by aspirin-intolerant asthmatic patients may contribute to their more severe clinical phenotype, and represents a novel paradigm for the development of chronic inflammatory disorders.

Topics: Adult; Aspirin; Asthma; Chromatography, High Pressure Liquid; Enzyme-Linked Immunosorbent Assay; Female; Humans; Hydroxyeicosatetraenoic Acids; Leukotriene C4; Lipoxins; Male; Middle Aged; Stereoisomerism

The effects of YM158 (3-[(4-tert-butylthiazol-2-yl)methoxy]-5'-[3-(4-chlorobenzenesu lfonyl )propyl]-2'-(1H-tetrazol-5-ylmethoxy)benzanilide monosodium salt monohydrate), a new dual antagonist for leukotriene D(4) and thromboxane A(2) receptors, on antigen-induced increases in airway resistance were investigated in mediator-controlled novel asthmatic models using actively sensitized guinea pigs. While the predominant mediator was thromboxane A(2), complete inhibition of cyclooxygenase induced mediation by cysteinyl-leukotrienes. About 1-mg/kg indomethacin induced a state where both mediators participated equally. YM158 inhibited increases in resistance whether only one or both mediators were involved. When leukotriene D(4) and thromboxane A(2) equally participated, ED(50) values for 4-oxo-8-[4-(4-phenylbutoxy)benzoylamino]-2-(tetrazol-5-yl)-4 H-1-benzo pyran hemihydrate (pranlukast; 3.9 mg/kg) and 7-(3,5,6-trimethyl-1, 4-benzoquinon-2-yl)-7-phenylheptanoic acid (seratrodast; 2.1 mg/kg) were similar to that for YM158 (8.3 mg/kg), although those effects on the corresponding mediator-induced reaction were 10 times stronger than those of YM158. Additionally, the maximum inhibition of YM158 was stronger than those of either single receptor antagonist. In conclusion, YM158 has a potentially greater efficacy in wider types of experimental asthmatic models than single receptor antagonists.

Topics: Administration, Oral; Airway Resistance; Animals; Anti-Asthmatic Agents; Anti-Inflammatory Agents, Non-Steroidal; Antigens; Asthma; Benzoquinones; Chromones; Dose-Response Relationship, Drug; Guinea Pigs; Heptanoic Acids; Indomethacin; Leukotriene Antagonists; Leukotriene B4; Leukotriene C4; Leukotriene E4; Lipid Metabolism; Lung; Male; Membrane Proteins; Ovalbumin; Receptors, Leukotriene; Receptors, Thromboxane; Tetrazoles; Thiazoles; Thromboxane B2; Time Factors

Leukotrienes (LTs) are pro-inflammatory mediators that contribute to the pathophysiological features of asthma. The relationship between the amounts of LTB4 and LTC4 produced by the leukocytes of asthmatic patients on the one hand and immunoglobulin E (IgE)-mediated allergy, asthma exacerbations and bronchial hyperresponsiveness was studied. Leukocytes were obtained from peripheral blood drawn from 29 atopic and 27 nonatopic asthmatics during exacerbations and clinically controlled periods, as well as from 20 control individuals. The leukocytes were stimulated with calcium ionophore A23187 to induce LTB4 and LTC4 production. Allergy was assessed by means of specific serum IgE or by positive skin tests, whereas bronchial hyperresponsiveness was measured by methacholine challenge. The leukocytes of the asthmatics generated significantly more LTB4 (p<0.05) and LTC4 (p<0.01) than those of controls. The leukocytes of patients with atopic asthma generated significantly more LTC4 than those of patients with nonatopic asthma (p<0.01). Significantly more LTC4 was produced by leukocytes obtained during exacerbations, than by those obtained during clinically controlled periods (p<0.01). In addition, there was a significant correlation between LTB4 generation by leukocytes and the degree of bronchial hyperresponsiveness to methacholine (r=-0.792, p<0.0001). These results suggest that leukotriene C4 production by leukocytes is associated with immunoglobulin E-mediated allergy and asthma exacerbations, and further that generation of leukotriene B4 is closely related to bronchial hyperresponsiveness in patients with asthma.

Topics: Asthma; Bronchial Hyperreactivity; Female; Humans; Leukocytes; Leukotriene B4; Leukotriene C4; Male; Middle Aged

Hyperresponsiveness of airway smooth muscle accounts for the susceptibility of asthmatic subjects to diverse bronchoconstrictor agents. It is widely presumed that hyperresponsiveness is not spasmogen selective. Hence, inhalation of methacholine is used routinely for clinical assessment of asthma and for evaluation of anti-asthma drugs. Comparative studies employing multiple spasmogens have revealed hyperresponsiveness to be markedly spasmogen selective. Because of this pronounced heterogeneity of hyperresponsiveness, sensitivity to methacholine cannot provide a reliable index of responsiveness. Development of exceptional hyperresponsiveness to bradykinin and to peptidoleukotrienes during allergic and other reactions could warrant the development of specific antagonists for asthma therapy. These issues are discussed here by Brian O'Connor, Simon Crowther, John Costello and John Morley.

Topics: Albuterol; Animals; Asthma; Bradykinin; Bronchial Hyperreactivity; Bronchoconstrictor Agents; Bronchodilator Agents; Humans; Leukotriene C4; Methacholine Chloride

Alcohol-induced bronchoconstriction is due to high blood concentrations of acetaldehyde, a metabolic product of ethanol, which lead to the release of histamine from basophils and mast cells.. We examined the inhibitory effects of azelastine hydrochloride, which inhibits histamine release and blocks H1 receptors, in alcohol-induced asthma.. Subjects were 13 Japanese asthmatic patients. We measured the change in FEV1 after ingestion of 30 g of pure ethanol. Blood ethanol, acetaldehyde, histamine, leukotriene C4 (LTC4), and thromboxane B2 (TXB2) concentrations were also measured. Alcohol challenge test was repeated in responders after administration of azelastine for 1 week at 4 mg/day.. Of 13 asthmatic patients, five (38.5%) tested positive during an ethanol challenge test, represented by a fall more than 20% in FEV1. The responders had a high blood ethanol, and showed a rise in blood acetaldehyde and histamine concentrations, but not in LTC4 or TXB2. After azelastine treatment, there was no significant fall in FEV1 among responders. Neither the rise in blood ethanol nor blood acetaldehyde levels were blunted by treatment with azelastine, but the rise in blood histamine was blunted by this treatment.. Our results suggest that antihistamine agents may be effective against alcohol-induced asthma by both blocking H1 receptors and inhibiting histamine release.

Topics: Acetaldehyde; Adult; Aged; Asthma; Bronchoconstrictor Agents; Bronchodilator Agents; Ethanol; Female; Histamine; Humans; Leukotriene C4; Male; Middle Aged; Phthalazines; Respiratory Function Tests; Thromboxane B2

The etiology and treatment of premenstrual exacerbations of asthma (PMA) remain uncertain.. We investigated the role of cellular mediators released from inflammatory cells in the airflow limitation during PMA.. Serum levels of leukotriene (LT) B(4), LTC(4), platelet- activating factor, histamine, IL-1beta, IL-4, IL-5, IL-6, and GM-CSF were measured at different time points, first just before or during menstruation when the peak expiratory flow rate (PEFR) began to decrease precipitously and second during the menstrual midcycle week (days 10-16) when the PEFR returned to baseline values in patients with PMA and in age-matched asthma patients without PMA at the same intervals.. Serum levels of LTC(4) were significantly higher during exacerbations of asthma than after recovery (69.0 +/- 16.0 pg/mL vs 24.0 +/- 9.5 pg/mL, P <.05), whereas those of IL-1beta, IL-4, IL-5, IL-6, GM-CSF, histamine, LTB(4), and platelet-activating factor did not differ between 2 periods in 5 patients with PMA. In contrast, in 5 asthmatic patients without PMA serum levels of cellular mediators did not differ between corresponding periods. Oral administration of pranlukast, an LT receptor antagonist (225 mg twice daily), significantly reduced decreases in PEFR from the baseline values (110 +/- 21 L/min with pranlukast vs 233 +/- 20 L/min without pranlukast, P <.01) in association with an improvement of asthma symptom scores (6.5 +/- 1. 1 with pranlukast vs 9.8 +/- 0.7 without pranlukast, P <0.05) in 5 patients with PMA.. LTs are partly involved in the pathogenesis of PMA, and LT receptor antagonists may be useful for preventing airflow obstruction in patients with PMA.

Topics: Adolescent; Adult; Anti-Asthmatic Agents; Asthma; Chromones; Cytokines; Female; Histamine; Humans; Leukotriene Antagonists; Leukotriene B4; Leukotriene C4; Mast Cells; Menstruation; Peak Expiratory Flow Rate; T-Lymphocytes

Passive sensitization of human airways in vitro causes increased responsiveness to histamine and induces specific immunoglobulin (Ig)E-dependent contractile responsiveness to allergen. Leukotrienes (LTs) and, to a lesser extent, histamine are the major mediators of allergen-induced contraction. Since it is unclear whether passively sensitized airways are also hyperresponsive to cysteinyl leukotrienes, this study investigated the effect of passive sensitization on LTC4-, in addition to histamine- and allergen-induced contractions in vitro. Bronchial rings from nine nonatopic patients were sensitized overnight with serum containing high levels of total IgE (>250 U x mL(-1)) and allergen-specific IgE against Dermatophagoides farinae (fluorescence allergosorbent test) (FAST class > or =3). The potency (-log10 of the mediator concentration causing a half maximal response (pEC50) of histamine was significantly increased in serum-sensitized tissues compared to nonsensitized controls ((mean+/-SEM) pEC50 5.20+/-0.27 versus 5.64+/-0.18; p=0.02) and maximal contractions were enhanced (877+/-47 versus 543+/-51 mg; p<0.0001). Similarly, the potency of LTC4 was significantly increased in sensitized compared to nonsensitized bronchial rings (pEC50 9.37+/-0.20 versus 8.66+/-0.26; p=0.004); maximal contractions were also enhanced (811+/-57 versus 361+/-86 mg; p<0.0001). These data demonstrate that passive sensitization of human airways induces an increase not only in histamine but also in leukotriene responsiveness. Therefore, it might be speculated that allergen responses in sensitized airways are effected through a combination of increased mediator release from inflammatory cells and increased responsiveness of airway smooth muscle.

Topics: Adult; Aged; Allergens; Asthma; Bronchial Provocation Tests; Bronchoconstriction; Carbachol; Dose-Response Relationship, Drug; Female; Histamine; Humans; Immunoglobulin E; In Vitro Techniques; Isoproterenol; Leukotriene C4; Male; Middle Aged; Respiratory Hypersensitivity

Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) are members of the immunoglobulin superfamily adhesion molecules on vascular endothelium and important in the development of eosinophil (EOS) accumulation in allergic inflammation. To define the role of these adhesion proteins in EOS inflammation, peripheral blood EOS from allergic donors were incubated in either buffer (control)-, recombinant human (rh)-VCAM-1-, or rh-ICAM-1-coated plates, and the effects of these adhesion proteins on EOS effector functions were determined. VCAM-1 induced spontaneous EOS adhesion whereas EOS adhesion to ICAM-1 required a second signal, such as granulocyte macrophage colony-stimulating factor (GM-CSF). Although only VCAM-1 stimulated EOS superoxide anion (O2-) generation, the addition of GM-CSF (100 pM) to the reactions resulted in a greater and equivalent production of O2- with VCAM-1 and ICAM-1. In the presence of GM-CSF, ICAM-1 and VCAM-1 caused significant release of EOS-derived neurotoxin (EDN). Moreover, only ICAM-1 (no GM-CSF) promoted calcium ionophore A23187 (0.2 microM)-induced EOS leukotriene C4 (LTC4). Enhanced O2- generation, EDN release, and LTC4 generation observed with ICAM-1 and VCAM-1 were significantly inhibited by anti-beta2-integrin antibody. These results suggest that ICAM-1 and VCAM-1 are important in determining the eventual function of airway EOS.

Topics: Adult; Antibodies; Antigens, CD; Asthma; CD18 Antigens; Cell Adhesion; Eosinophil-Derived Neurotoxin; Eosinophils; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Integrin alpha4; Intercellular Adhesion Molecule-1; Leukotriene C4; Middle Aged; Proteins; Recombinant Proteins; Rhinitis, Allergic, Perennial; Ribonucleases; Superoxides; Vascular Cell Adhesion Molecule-1

The release of histamine and leukotriene C4 (LTC4) from bronchoalveolar lavage (BAL) cells and peripheral blood stimulated with Ca ionophore A23187 was compared between atopic and nonatopic asthma. The proportion of basophilic cells in BAL fluid was significantly higher in atopic than in nonatopic asthma (p < 0.01); however, no significant differences were present in the other BAL cells between the two asthma types. The concentration of histamine in BAL fluid was significantly higher in younger patients (20-59 years) with atopic than in nonatopic asthma (p < 0.01). In contrast, the concentration of LTC4 was significantly higher in nonatopic than in younger patients with atopic asthma (p < 0.01). The release of histamine from BAL cells (p < 0.001) and peripheral blood (p < 0.01) was significantly larger in younger patients with atopic than in nonatopic asthma. The generation of LTC4 by BAL cells was significantly larger in nonatopic than in younger (p < 0.01) and older patients with atopic asthma (60+ years) (p < 0.05). These results suggest that both histamine and LTC4 participate in the onset mechanism of atopic asthma, and only LTC4 participates in that of nonatopic asthma.

Topics: Adult; Aging; Asthma; Blood Cells; Bronchi; Bronchoalveolar Lavage Fluid; Calcimycin; Female; Histamine; Humans; Hypersensitivity; Ionophores; Leukotriene C4; Male; Middle Aged; Pulmonary Alveoli

There are substantial numbers of reports showing that leukotrienes (LTs) play important roles in adult asthma. No definite evidence has been demonstrated that LTs are involved in asthma attacks in children, although it is highly expected. In this report, we demonstrated that the levels of LTB4 and LTC4 but not thromboxane B2 (TXB2), a stable metabolite of TXA2, were significantly elevated in the bronchoalveolar lavage fluid, which was obtained from intubated and mechanically ventilated children with severe asthma attacks. This is direct evidence that LTB4 and LTC4 predominantly participate in asthma attacks in pediatric patients.

Topics: Adolescent; Asthma; Child, Preschool; Female; Humans; Leukotriene B4; Leukotriene C4; Male; Thromboxane A2

We examined the action of Shinpi-To (Formula divinita; TJ-85), a granular extract of seven Chinese medicinal herbs that is used in treating childhood asthma, on the leukotriene synthesis in rat basophilic leukemia-2H3 cells (RBL-2H3 cells). IgE-loaded cells were stimulated with anti-IgE serum in the presence or absence of Shinpi-To. Released LTC4 and LTB4 were measured by radioimmunoassay (RIA). Shinpi-To significantly inhibited IgE-mediated synthesis of leukotriene (LT)C4 and LTB4. To identify the inhibitory sites, we investigated the action of this extract on four synthetic enzymes, phospholipase A2 (PLA2), 5-lipoxygenase (5-LO). LTC4 synthase, and LTA4 hydrolase. Shinpi-To inhibited the A23187-stimulated release of [3H]arachidonic acid (AA) from the cell membrane, reflecting an effect on PLA2 activity. It also suppressed production of LTC4 and LTB4 when cell lysates were incubated with AA as substrate. It did not inhibit the production of LTC4 and LTB4 when LTA4-free acid was used as the substrate. Shinpi-To did not inhibit the IgE-mediated increase of intracellular Ca2+ ([Ca2+]i) concentration. Results indicate that Shinpi-To inhibits LT synthesis by inhibiting PLA2 and 5-LO activities without affecting the mobilization of [Ca2+]i.

Topics: Analysis of Variance; Animals; Arachidonic Acid; Asthma; Bronchodilator Agents; Calcimycin; Calcium; Cell Membrane; Drugs, Chinese Herbal; Ephedrine; Immunoglobulin E; Ionophores; Isotope Labeling; Leukemia, Basophilic, Acute; Leukotriene A4; Leukotriene B4; Leukotriene C4; Lipoxygenase Inhibitors; Phospholipases A; Phospholipases A2; Radioimmunoassay; Rats; Tritium; Tumor Cells, Cultured

Cysteinyl leukotrienes (C-LTs) are local inflammatory mediators involved in bronchial asthma. Seventeen asthmatic patients (FEV1 ranging from 41 to 99.8% of predicted values) and 11 healthy subjects were studied. The clinical severity of asthma was assessed by the Aas score. Plasma C-LTs were measured by enzyme immunoassay (EIA) after sample purification by solid-phase extraction (SPE), to investigate whether differences may exist between asthmatic and control subjects and whether leukotriene E4 (LTE4) levels were related to the severity of disease. LT measurements showed that 87.6 +/- 1.2% was recovered as LTE4 and 9.4 +/- 1.3% as LTC4. In asthmatic subjects, LTE4 plasma levels were found to be significantly higher than those in the control group (1.073 +/- 0.133 and 0.53 +/- 0.19 ng/ml of plasma, respectively; P < 0.002). Moreover, there was a significant correlation between LTE4 plasma levels and the Aas clinical score (P < 0.005). These data suggest that plasma LTE4 levels might be used to assess the severity of asthma.

Topics: Adolescent; Adult; Aged; Asthma; Biomarkers; Humans; Immunoenzyme Techniques; Leukotriene C4; Leukotriene E4; Leukotrienes; Middle Aged; Severity of Illness Index

A role of prostaglandins (PGs) and leukotrienes (LTs) in the pathogenesis of nasal polyps has been recently suggested. Cyclooxygenase (CO) products (thromboxane B2, PGE2 and 6-keto PGF1 alpha) and lipoxygenase (LO) products (LTB4 and LTC4) were investigated by radioimmunoassay in polyps, hypertrophic turbinates and nasal mucosa from 14 patients with non-allergic (n = 6), allergic chronic rhinitis (n = 6) and aspirin-sensitive asthma (ASA) (n = 2), who underwent polypectomy. In all tissues CO metabolite levels were found higher than LO products (P < 0.01). Nasal polyps showed a significantly lower (P < 0.05) arachidonic acid (AA) metabolism in comparison to nasal mucosa. In polyps of allergic patients significantly higher LTB4 levels (P < 0.001) and a tendency to produce higher amounts of CO products in comparison to non-allergic subjects were observed, whereas in turbinates of non-allergic patients LT levels were significantly higher in comparison to those of allergic ones (P < 0.01). In ASA patients a decreased CO/LO ratio was found supporting the hypothesis of an imbalance of AA metabolism in this syndrome. These findings seem to indicate that the occurrence of nasal polyps may represent the result of different chronic inflammatory stimuli, regulated in part by AA metabolites.

Topics: 6-Ketoprostaglandin F1 alpha; Adult; Arachidonic Acid; Asthma; Dinoprostone; Humans; Leukotriene B4; Leukotriene C4; Lipoxygenase; Middle Aged; Nasal Mucosa; Nasal Polyps; Prostaglandin-Endoperoxide Synthases; Rhinitis; Thromboxane B2; Turbinates

To elucidate the mechanism of development of asthma, we tried to develop a model which elicited a late asthmatic response by a combination of systemic and inhaled sensitization with ovalbumin in guinea pigs. Eighty-seven percent of animals elicited both an immediate and late asthmatic response after the third antigen inhalation. Airway eosinophilia and airway hyperresponsiveness (AHR) induced after the third challenge were more severe than those after the first challenge. There was a good correlation between airway eosinophilia and AHR in this model under experimental modulation of the number of eosinophils, such as by interleukin 5 or antieosinophil antibody injection. These results demonstrate that eosinophils play an important role in the development of late asthmatic response and AHR.

Topics: Animals; Antibodies; Asthma; Bronchial Hyperreactivity; Bronchial Provocation Tests; Bronchoalveolar Lavage Fluid; Bronchoconstrictor Agents; Disease Models, Animal; Eosinophils; Guinea Pigs; Histamine; Interleukin-5; Leukocyte Count; Leukotriene C4; Male; Methacholine Chloride; Ovalbumin; Passive Cutaneous Anaphylaxis; Pulmonary Eosinophilia; Thromboxane B2; Time Factors

Topics: Animals; Asthma; Cyclosporine; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Freund's Adjuvant; Guinea Pigs; Histamine Release; Immunosuppressive Agents; Leukotriene C4; Leukotriene D4; Leukotriene E4; Male; Muscle Contraction; Muscle, Smooth; Ovalbumin; Radioimmunoassay; Trachea

Eosinophils from asthmatic patients are known to release greater amounts of leukotrienes than normal eosinophils when stimulated by the calcium ionophore A23187. The effect of platelet activating factor (PAF) in priming eosinophils was investigated.. Eosinophils were obtained from 18 asthmatic patients and 18 healthy donors. Cells separated by the Percoll gradients were incubated with PAF (C-18) for 30 minutes and then stimulated with the calcium ionophore A23187 (2.5 microM) for 15 minutes. The amount of leukotriene C4 (LTC4) in supernatants was measured using a combination of high pressure liquid chromatography and radioimmunoassay.. The mean (SD) amount of LTC4 released by eosinophils from asthmatic patients upon stimulation with the calcium ionophore A23187 alone was 27.9 (9.9) ng/10(6) cells (n = 6). The amount of LTC4 released following stimulation with the calcium ionophore A23187 after pretreatment with PAF (1, 5, and 10 microM) was 57.2 (8.9), 75.1 (14.3), and 52.6 (10.7) ng/10(6) cells (n = 6), respectively. Trace amounts of LTC4 (0.9 (0.02) ng/10(6) cells, n = 6) were detected in the supernatant of the cells after stimulation by PAF alone (5 microM). The amount of LTC4 released upon stimulation by calcium ionophore A23187 alone in eosinophils from healthy donors was 10.3 (3.7) ng/10(6) cells (n = 4). The amounts of LTC4 released upon stimulation with calcium ionophore A23187 after pretreatment with PAF at concentrations of 1, 5, and 10 microM were 11.9 (3.5), 17.8 (5.6), and 12.7 (5.1) ng/10(6) cells (n = 4), respectively. Trace amounts of LTC4 (0.6 (0.02) ng/10(6) cells, n = 4) were detected in the supernatant of the cells upon stimulation with PAF alone (5 microM). The amounts of LTC4 released upon stimulation with calcium ionophore A23187 after pretreatment with lyso-PAF at concentrations of 1, 5, and 10 microM (n = 4 or 6) were 30.8 (5.2), 22.9 (5.1), and 27.3 (4.3) ng/10(6) cells (n = 6) from the eosinophils of asthmatic patients and 13.7 (3.3), 15.2 (4.9), and 14.7 (3.8) ng/10(6) cells (n = 4) from the eosinophils of healthy donors.. The results indicated that PAF enhanced LTC4 formation by eosinophils obtained from asthmatic patients stimulated with the calcium ionophore A23187, but not those obtained from normal subjects.

Topics: Adult; Aged; Asthma; Calcimycin; Chromatography, High Pressure Liquid; Eosinophils; Humans; In Vitro Techniques; Leukotriene C4; Male; Middle Aged; Platelet Activating Factor; Stimulation, Chemical

Salmeterol is a long-acting beta 2-adrenoceptor agonist, with several antiasthma properties. Nimesulide is a nonsteroidal anti-inflammatory drug, supposed to act by inhibition of phosphodiesterase type IV. This might indicate that the effects of both drugs are mediated by an increase in cyclic adenosine monophosphate (cAMP). For salmeterol, it has been shown that it inhibits the influx of eosinophils into the lungs of guinea-pigs after platelet-activating factor (PAF) challenge, suggesting an effect of cAMP on eosinophil migration. For neutrophils, it has been shown that PAF synthesis is inhibited by cAMP. In the present study, we have, therefore, measured the effect of salmeterol and nimesulide on two important human eosinophil functions: chemotaxis; and synthesis of PAF and leukotriene C4 (LTC4). Both drugs were found to be inhibitors of the chemotactic responses of human eosinophils. However, at comparable concentrations, only nimesulide was able to inhibit the synthesis of PAF and LTC4 in activated eosinophils. These results indicate that although the effects of both drugs are thought to be mediated by an increase in cyclic adenosine monophosphate, they have differential effects on eosinophil chemotaxis and synthesis of lipid mediators.

Topics: Adrenergic beta-Agonists; Albuterol; Animals; Anti-Inflammatory Agents, Non-Steroidal; Asthma; Chemotaxis; Complement C5a; Cyclic AMP; Eosinophils; Granulocyte-Macrophage Colony-Stimulating Factor; Guinea Pigs; Humans; Leukotriene C4; Platelet Activating Factor; Salmeterol Xinafoate; Sulfonamides

Inhalation of antigen in immunized mice induces an infiltration of eosinophils into the airways and increased bronchial hyperreactivity as are observed in human asthma. We employed a model of late-phase allergic pulmonary inflammation in mice to address the role of leukotrienes (LT) in mediating airway eosinophilia and hyperreactivity to methacholine. Allergen intranasal challenge in OVA-sensitized mice induced LTB4 and LTC4 release into the airspace, widespread mucus occlusion of the airways, leukocytic infiltration of the airway tissue and broncho-alveolar lavage fluid that was predominantly eosinophils, and bronchial hyperreactivity to methacholine. Specific inhibitors of 5-lipoxygenase and 5-lipoxygenase-activating protein (FLAP) blocked airway mucus release and infiltration by eosinophils indicating a key role for leukotrienes in these features of allergic pulmonary inflammation. The role of leukotrienes or eosinophils in mediating airway hyperresponsiveness to aeroallergen could not be established, however, in this murine model.

Topics: 5-Lipoxygenase-Activating Proteins; Allergens; Animals; Asthma; Bronchial Provocation Tests; Bronchoconstrictor Agents; Carrier Proteins; Disease Models, Animal; Female; Immunoglobulin E; Inflammation; Leukotriene B4; Leukotriene C4; Lipoxygenase Inhibitors; Membrane Proteins; Methacholine Chloride; Mice; Mice, Inbred BALB C; Mucus; Ovalbumin; Pulmonary Eosinophilia; Respiratory Function Tests; Respiratory System

Studies of in vitro eosinophil function are dependent on efficient and reliable methods of cell isolation. Protocols using Percoll or metrizamide density gradients have been of limited use in isolating peripheral blood eosinophils in sufficient numbers and purity from subjects with normal or only slightly elevated eosinophil counts, thereby restricting comparative studies to preparations from hypereosinophilic subjects. Recently, a method utilizing negative selection by anti-CD16 coated magnetic beads has greatly improved eosinophil isolation by dramatically increased yields and purity. However, little is known as to the differential effect of various isolation methods on the functional activity of eosinophils. In this study, eosinophils were isolated by either discontinuous multiple density Percoll gradients or anti-CD16-coated magnetic beads: several functional activities were then compared using cells obtained by the two methods of isolation. Compared with Percoll isolated eosinophils, anti-CD16 bead separated eosinophils had significantly increased baseline and stimulated LTC4 production, spontaneous O2- generation, and expression of specific cell surface markers. No significant difference was observed in the cells' in vitro survival and adhesion. Such differences may be due to the isolation of eosinophils of all densities by anti-CD16 beads, or the effect of neutrophils interacting with the beads to release eosinophil agonists or primers. Alternatively, the Percoll gradient method with the eosinophils' exposure to dextran and Ficoll-Hypaque may affect subsequent cell function. Therefore, comparison of eosinophil function between cells isolated by different protocols must be considered before concluding which is the true measure of in vivo cell function.

Topics: Adolescent; Adult; Antibodies, Monoclonal; Asthma; Cell Adhesion; Cell Separation; Centrifugation, Density Gradient; Colloids; Endothelium, Vascular; Eosinophils; Flow Cytometry; Humans; Immunomagnetic Separation; Leukotriene C4; Middle Aged; Povidone; Receptors, IgG; Rhinitis, Allergic, Seasonal; Silicon Dioxide; Umbilical Veins

To study the asthmatogenic effect of certain airborne elements of the home environment, we studied a group of guinea pigs exposed to aerosolized cockroach allergen (CRa) and side-stream cigarette (S-SC) smoke. Four groups of guinea pigs were exposed to aerosols, either saline or CRa, for 4 weeks, after a sham or S-SC smoke pretreatment. Anaphylactic antibodies were measured by passive cutaneous anaphylaxis (PCA) assay and by skin test. Animals were challenged with aerosol CRa on day 35, and lung function and leukotrienes (LTB4 and LTC4/D4) were measured. Skin tests were positive on days 21 and 29. The antibodies were heat-stable, IgG1a-like antibodies (PCA titers 1:2-18). The CRa challenge caused an immediate reduction in both the maximal expiratory flow rate at 50% of the lung capacity and respiratory compliance. The decreased lung function continued for up to 6 h (p < 0.0001). LTB4 and LTC4/D4 were elevated (p < 0.0001) in the sensitized animals at the corresponding times of reduced lung function. S-SC smoke did not affect the CRa sensitization; instead, a protective effect on the CRa-induced bronchospasms was noted. Thus, the study indicates that a simple airborne CRa exposure without an adjuvant sensitizes guinea pigs, and that the animals respond to antigen challenge with CRa-specific airway obstructions.

Topics: Aerosols; Air Pollution, Indoor; Allergens; Animals; Asthma; Cockroaches; Disease Models, Animal; Environmental Exposure; Guinea Pigs; Immunoglobulin G; Leukotriene B4; Leukotriene C4; Leukotriene D4; Lung; Male; Passive Cutaneous Anaphylaxis; Respiratory Function Tests; Skin Tests; Tobacco Smoke Pollution

The ability of linetastine (TMK688, 1-[¿5'-(3"-methoxy-4"-ethoxycarbonyloxyphenyl)-2',4'-pentadieno yl¿ aminoethyl]-4-diphenylmethoxypiperidine, CAS 110501-66-1) to inhibit leukotriene production and to antagonize the effect of histamine was examined in comparison with the ability of azelastine, an antiallergic drug having an antihistamine activity. Linetastine and its active metabolite TMK777 (1-[¿5'-(3"-methoxy-4"-hydroxyphenyl)-2',4'-pentadienoyl¿ aminoethyl]-4-diphenylmethoxypiperidine, CAS 101619-11-8) inhibited the release of leukotrienes B4 and C4 from calcium ionophore-stimulated human leukocytes. The respective IC50 values of leukotriene B4 were 1.2 x 10(-7) mol/l and 8.6 x 10(-8) mol/l, and those of leukotriene C4 were 1.5 x 10(-7) mol/l and 7.1 x 10(-8) mol/l. Azelastine also inhibited the release of leukotriene B4 and C4, but its IC50 values were higher than 1 x 10(-5) mol/l. Linetastine at 1-10 mg/kg p.o. inhibited the increase in leukotriene B4 and C4 production in the lungs during late asthmatic responses in actively sensitized guinea-pigs. The effect of 3.2 mg/kg lasted for more than 16 b. Since repeated oral administration of linetastine, 1 mg/kg once a day for 7 successive days, showed the same inhibitory effect on the increase in respiratory resistance and the leukotriene production as single oral administration, the effect of linetastine was neither tachyphylactic nor cumulative. Azelastine at 10 mg/kg had no effect on the leukotriene production. Linetastine TMK777 and azelastine dose-dependently inhibited the histamine-induced contraction of isolated guinea-pig trachea in a noncompetitive manner, the respective pD2 values were 7.28, 7.98 and 8.07. Linetastine inhibited histamine-induced bronchoconstriction dose-dependently at 1-10 mg/kg (p.o.) in guinea-pigs, and the effect lasted for more than 24 h. Repeated oral administration of linetastine, 0.32 to 3.2 mg/kg once a day for 7 successive days inhibited the histamine-induced bronchoconstriction, the same as single oral dosing. Azelastine at 0.32 mg/kg p.o. also showed antihistamine activity. In conclusion, linetastine inhibits both the production of leukotrienes and the effect of histamine at almost the same dose and the effects were long lasting.

Topics: Animals; Arachidonate 5-Lipoxygenase; Asthma; Bronchoconstriction; Female; Guinea Pigs; Histamine Antagonists; Humans; In Vitro Techniques; Leukocytes; Leukotriene B4; Leukotriene C4; Lipoxygenase Inhibitors; Lung; Male; Mammary Neoplasms, Experimental; Mast-Cell Sarcoma; Mice; Piperidines; Stimulation, Chemical; Trachea; Tumor Cells, Cultured

To determine whether ONO-1078, leukotriene receptor antagonist, inhibits the activation of eosinophils, we investigated the effect of ONO-1078 on the release of leukotriene (LTC4) and eosinophil cationic protein (ECP) from human peripheral blood eosinophils of allergic patients and normal subjects. After preincubation with ONO-1078, eosinophils were incubated with calcium ionophore (A23187). ONO-1078 10(-5) and 10(-6) M inhibited LTC4 release of allergic patients eosinophils and 10(-5)-10(-9) M inhibited LTC4 release of normal subjects eosinophils. ONO-1078, 10(-5) M, also inhibited ECP release of eosinophils obtained from both asthma patients and normal subjects. We think that ONO-1078 may have another pharmacological effect to prevent the activation of human peripheral blood eosinophils by inhibiting LTC4 and ECP release. These results suggest that ONO-1078 might be useful in controlling bronchial asthma.

Topics: Asthma; Blood Proteins; Cells, Cultured; Chromones; Depression, Chemical; Eosinophil Granule Proteins; Eosinophils; Female; Humans; Leukotriene Antagonists; Leukotriene C4; Male; Ribonucleases

Eosinophils generate and release leukotrienes C4 and B4 (LTC4, LTB4) and platelet activating factor (PAF), all of which have the capacity to cause inflammation and tissue injury in the airways. This study has examined the effects of a new 5-lipoxygenase inhibitor, 6-hydroxy-2-(4-sulfamoylbenzylamino)-4,5,7-trimethylbenzothiazo le hydrochloride (CAS 120164-49-0, E6080) on the release of LTC4, LTB4 and PAF by human eosinophils, Eosinophils stimulated by 1 mumol/l calcium ionophore A23187 for 15 min released 37.5 +/- 2.2 ng, 2.3 +/- 0.3 ng and 4.0 +/- 0.3 pmol per 10(6) cells of immunoreactive LTC4, LTB4 and PAF, respectively (mean +/- SEM, n = 4). LTC4 and LTB4 releases were inhibited dose-dependently by the addition of E6080 to the cell suspension. The IC50 values were 0.26 mumol/l for LTC4 and 0.23 mumol/l for LTB4. PAF release was not inhibited. These results suggest that E6080 is a potent inhibitor of LTC4 and LTB4 release from eosinophils and may provide a protective effect against bronchoconstriction during late-phase asthmatic responses.

Topics: Asthma; Calcimycin; Dose-Response Relationship, Drug; Eosinophils; Humans; In Vitro Techniques; Ionophores; Leukotriene B4; Leukotriene C4; Lipoxygenase Inhibitors; Platelet Activating Factor; Thiazoles

Leukotrienes may mediate bronchoconstriction in asthma. Cysteinyl leukotriene production rises in vivo after allergen challenge, but few reports describe leukotriene concentrations in clinical asthma or in children. Using high performance liquid chromatography/radioimmunoassay, plasma and urinary leukotrienes in asthmatic children (aged 5-10 years) were measured during an acute exacerbation (peak expiratory flow (PEF) < 65%, n = 10) and one month later (PEF 74-169%, n = 9), and in non-atopic normal children (aged 1.3-13.2 years). In the asthmatics, geometric mean (95% confidence interval) plasma leukotriene B4 (LTB4) was 746 pg/ml (398 to 1403) acutely and 1026 pg/ml (662 to 1593) in remission, compared with 369 pg/ml (167 to 728) in the normal children (n = 14). Plasma cysteinyl leukotrienes were low or undetectable, but urinary leukotriene E4 (LTE4) was higher in the asthmatics during an acute episode (210 pmol/mmol creatinine, 101 to 454) and at follow up (179 pmol/mmol, 110 to 293), compared with the normal children (98 pmol/mmol, 81 to 118, n = 41). This persistent increase in plasma LTB4 and urinary LTE4 concentrations one month after a severe asthmatic episode suggests leukotriene production is related to chronic inflammation rather than to acute bronchoconstriction.

Topics: Acute Disease; Adolescent; Asthma; Child; Child, Preschool; Chromatography, High Pressure Liquid; Humans; Leukotriene B4; Leukotriene C4; Leukotriene E4; Radioimmunoassay

The effect of fibronectin on leukotriene C4 (LTC4) production by eosinophils was examined. Eosinophils obtained from patients with bronchial asthma were cultured for 3 h with or without fibronectin and culture supernatants were assayed for LTC4 by specific enzyme immunoassay. LTC4 was produced in a time- and dose-dependent manner in the presence of fibronectin, and maximum production of LTC4 was observed 3 h after addition of 100 micrograms/ml of fibronectin. These results suggest that eosinophils may be activated by interaction with extracellular matrix proteins, including fibronectin, and play a role in the pathogenesis of bronchial asthma.

Topics: Asthma; Eosinophils; Fibronectins; Humans; In Vitro Techniques; Leukotriene C4

We investigated the release of leukotriene C4 from eosinophils of asthmatic patients who were treated with or without intravenous prednisolone. The mean level of LTC4 in the supernatant of A23187-stimulated eosinophils obtained from asthmatic patients during an attack was significantly lower with intravenous prednisolone than without prednisolone treatment. Findings suggest that intravenous prednisolone inhibits the release of LTC4 from the eosinophils of asthmatic patients by acting on these cells in vivo.

Topics: Adult; Aged; Anti-Asthmatic Agents; Asthma; Cell Separation; Centrifugation, Density Gradient; Eosinophils; Humans; In Vitro Techniques; Leukotriene C4; Middle Aged; Prednisolone; Radioimmunoassay; Reference Values

To assess the relation among eosinophil-related variables in the peripheral blood, bronchial hyperreactivity, and the presence of atopic dermatitis in children aged 5-14 years, we studied 11 patients with atopic dermatitis alone, six with asthma and atopic dermatitis, 12 with asthma alone, and 12 healthy controls. Eosinophil counts, levels of eosinophil cationic protein, and the capacity of eosinophils to generate leukotriene (LT) C4, as well as bronchial hyperreactivity and a severity score for atopic dermatitis, were determined. Eosinophil variables were significantly higher in both patient groups with atopic dermatitis than in normal controls. In particular, ionophore A 23187 LTC4 generation was higher in patients with atopic dermatitis alone (median 82, range 25-273 ng/10(6) cells) and patients with combined asthma and atopic dermatitis (median 68, range 32-583 ng/10(6) cells) than in normal controls (median 9, range 1-67 ng/10(6) cells). However, there was no difference between the group of atopic dermatitis patients with asthma and without asthma. We conclude that eosinophil variables in the peripheral blood are mainly influenced by the presence of atopic dermatitis, and not the presence and the severity of asthma in patients with both asthma and atopic dermatitis.

Topics: Adolescent; Asthma; Blood Proteins; Bronchial Hyperreactivity; Child; Child, Preschool; Dermatitis, Atopic; Eosinophil Granule Proteins; Eosinophils; Female; Humans; Immunoglobulin E; Inflammation Mediators; Leukocyte Count; Leukotriene C4; Male; Ribonucleases

Plasma from bronchial asthma patients and healthy controls was investigated for the content of lipoxygenase products. After lipid extraction using SEP-PAK C18 Cartridges, the lipoxygenase products were measured by Enzyme-Immunoassay. Elevated chemotactic B4 was found in plasma from asthmatic patients with mean value (483 +/- 75) pmol/L, while the mean value in normal healthy donors was (140 +/- 12.1) pmol/L (M +/- SE). The levels of spasmogenic cysteinyl containing leukotrienes were also very high in the bronchial asthma patients. Elevations of leukotriene B4 and cysteinyl containing leukotrienes were detected during attacks of bronchial asthma. These results suggest that leukotriene B4 may be important in the pathogenesis of bronchial asthma and confirmed that peptidoleukotrienes play a role as chemical mediators during the asthmatic attack.

Topics: Asthma; Humans; Leukotriene B4; Leukotriene C4

Aspirin-sensitive patients may be desensitized through a graded series of exposures to aspirin. We investigated the underlying mechanism of aspirin desensitization by measuring the release of leukotrienes B4 and C4 from calcium ionophore-stimulated peripheral blood monocytes. Compared with monocytes from normal volunteers (n = 5), monocytes from patients with aspirin-sensitive asthma (n = 10) released increased amounts of thromboxane B2 (1060 +/- 245 pg/ml vs 456 +/- 62 pg/ml), leukotriene B4 (861 +/- 139 pg/ml vs 341 +/- 44 pg/ml), and leukotriene C4 (147 +/- 31 pg/ml vs 56 +/- 6 pg/ml) at baseline. After aspirin desensitization, thromboxane B2 release was almost completely suppressed in both groups. Leukotriene B4 release was significantly decreased in the aspirin-sensitive group (484 +/- 85 pg/ml) but not in the normal subject group (466 +/- 55 pg/ml). The need for prednisone decreased significantly after patients were desensitized to aspirin (10.4 +/- 2.2 mg/day to 1.6 +/- 2.8 mg/day). These results demonstrate that desensitization to aspirin results in decreased monocyte leukotriene B4 release. On the basis of the bronchospastic and inflammatory potential of leukotrienes, the decrease in leukotriene release may contribute to the clinical improvement seen after aspirin desensitization.

Topics: Adult; Aspirin; Asthma; Desensitization, Immunologic; Female; Humans; Leukotriene B4; Leukotriene C4; Male; Middle Aged; Monocytes; Thromboxane B2

Leukotrienes are inflammatory mediators implicated in the pathogenesis of asthma. The capacity of inflammatory cells within the airways to generate leukotrienes may be altered in asthma. This hypothesis was tested using bronchoalveolar lavage (BAL) to sample cells within the airways from atopic asthmatic and normal subjects, and by measuring their capacity to generate leukotriene B4 (LTB4) and leukotriene C4 (LTC4) in response to A23187, a potent stimulus of leukotriene generation.. Bronchoalveolar lavage was performed in 12 mild asymptomatic atopic asthmatic patients and 12 normal subjects. Mixed BAL cell aliquots (approximately 80% alveolar macrophages) were incubated with 0-20 microM A23187 for 10 minutes and with 4 microM A23187 for 0-30 minutes, and leukotrienes were measured by radioimmunoassay and high performance liquid chromatography.. Mixed BAL cells from asthmatic subjects generated less LTB4 than cells from normal subjects in dose response and time course experiments (area under the curve 81.5 (0.0-228.5) ng.min.10(-6) cells in asthmatic subjects and 197.9 (13.9-935.6) ng.min.10(-6) cells in normal subjects. There were no differences in LTC4 generation between BAL cells from asthmatic and normal subjects.. Generation of LTB4 by BAL cells from atopic asthmatic subjects in response to A23187 was reduced. As the alveolar macrophage is the major source of LTB4 in BAL cells, these results probably reflect reduced generation of LTB4 by alveolar macrophages from asthmatic patients. This may be a consequence of monocyte migration into the lung, or altered alveolar macrophage function in asthma, or both.

Topics: Adult; Asthma; Bronchoalveolar Lavage Fluid; Calcimycin; Cell Count; Chromatography, High Pressure Liquid; Female; Humans; Leukotriene B4; Leukotriene C4; Macrophages, Alveolar; Male; Radioimmunoassay

The effects of three histamine H1 receptor antagonists, epinastine (CAS 80012-43-7, WAL-801 CL), ketotifen (CAS 34580-13-7) and oxatomide (CAS 60607-34-3), on mediator release have been studied in human peripheral leukocytes. When leukocytes from asthmatic patients sensitive to mite were stimulated with the allergen, epinastine inhibited histamine release with a concentration required for 50% inhibition (IC50) of 3 x 10(-5) mol/l and leukotriene C4 generation. On the other hand, ketotifen or oxatomide showed little inhibiting effect on histamine release elicited with the allergen. When the cells were stimulated with calcium ionophore A23187, epinastine failed to inhibit histamine release and leukotriene C4 generation. Oxatomide caused a concentration related inhibition of calcium ionophore-induced histamine release with the IC50 value of 5 x 10(-5) mol/l. Ketotifen or oxatomide also showed an inhibition of leukotriene C4 generation induced by calcium ionophore in a dose-dependent manner and the IC50 value was 6 x 10(-6) mol/l for oxatomide and 8 x 10(-5) mol/l for ketotifen, suggesting that oxatomide is a more potent inhibitor of leukotriene C4 generation than ketotifen. These results indicate that epinastine inhibits IgE-mediated histamine release and LTC4 generation, and oxatomide has a capacity to inhibit calcium ionophore-induced mediator release from human leukocytes. Additionally, when platelet activating factor was quantitated by radioimmunoassay in the supernatant and the cell pellet after ionophore stimulation, epinastine inhibited the formation and the secretion in a dose-dependent manner.

Topics: Asthma; Calcimycin; Dibenzazepines; Histamine H1 Antagonists; Humans; Hypersensitivity; Imidazoles; Immunoglobulin E; In Vitro Techniques; Ketotifen; Leukocytes; Leukotriene C4; Neutrophils; Piperazines; Platelet Activating Factor

In asthma, activation and recruitment of eosinophils to the bronchial mucosa amplifies many cellular functions. The blood eosinophil count and the number of hypodense eosinophils increase with asthma severity. Eosinophils produce numerous proinflammatory mediators in response to a variety of agonists, notably the peptido-leukotriene (LT) C4, a potent bronchoconstrictor. In this study, we have evaluated blood eosinophil LTC4 release and its modulation by cytokines in normal individuals and in subjects with asthma of various severities: mild (beta 2-agonist on demand); moderate (inhaled steroids on a regular basis); and severe (inhaled and oral steroids on a regular basis). Eosinophils were isolated using a modified Percoll gradient technique, which recovers both hypodense and normodense eosinophils in a global cell population. Eosinophils released detectable amounts of LTC4 only in the presence of the stimulus (calcium ionophore A23187, 2 microM). The ionophore-induced LTC4 release was greater in moderate asthmatics (mean +/- SEM 5.7 +/- 1.3 pg x 10(3)/250,000 eosinophils) than in normal individuals (1.6 +/- 0.4 pg x 10(3)/250,000 eosinophils), mild asthmatics (1.8 +/- 0.3 pg x 10(3)/250,000 eosinophils) and severe asthmatics (2.0 +/- 0.3 pg x 10(3)/250,000 eosinophils). Granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-5 (IL-5) amplified the ionophore-induced LTC4 release in the four groups from 1.9 to 2.6 and 1.9 to 2.8 fold, respectively. Interleukin-3 (IL-3) did not increase LTC4 production except by the eosinophils of the severe asthmatics whose ionophore-induced LTC4 production was enhanced by 1.9 fold. These data demonstrate that the asthmatic bronchial inflammatory process may modify blood eosinophil LTC4 release and its modulation by cytokines according to asthma severity and treatment.

Topics: Adult; Analysis of Variance; Asthma; Calcimycin; Cells, Cultured; Cytokines; Eosinophils; Female; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Inflammation Mediators; Interleukin-3; Interleukin-5; Ionophores; Leukotriene C4; Male; Middle Aged; Severity of Illness Index

The ex vivo release of leukotriene B4 (LTB4) and leukotriene C4 (LTC4) from leukocytes was evaluated after stimulation with both Ca-ionophore (Ca-I) and opsonized zymosan (OZ) in children with atopic asthma. Twenty-seven patients with asthma of varying severity were evaluated and divided into three groups: 1) moderate to severe asthma using inhaled steroids and symptom-free for the last 3 weeks (n = 8), 2) mild asthma with sporadic symptoms, only using inhaled beta 2-agonists < 3 times/week (n = 8), and 3) acute asthmatic attacks admitted to hospital (n = 11). A group of children without atopic disease or any other known disease served as controls (n = 15). Total serum IgE levels were significantly increased in the children with asthma compared with the control group. LTC4 production was only significantly increased in the group of children with moderate to severe asthma after stimulation with Ca-I, when compared with controls. In the same group, a trend towards increased LTC4 production after stimulation with OZ was found. LTB4 was not significantly increased in any patient group compared with the control group. A significant correlation between LTC4 production after stimulation with Ca-I, but not OZ, and the relative blood eosinophil count was found in all subjects. LTC4 generation per eosinophilic cell after stimulation with Ca-I or OZ was not statistically different in any patient group compared with the controls. We conclude that the increased leukotriene (LT) levels found after the stimulation of peripheral white blood cells sampled from atopic children with asthma are mainly the result of increased numbers of LT-producing cells, rather than due to increased releasability from these cells.

Topics: Adolescent; Asthma; Calcimycin; Child; Child, Preschool; Humans; Hypersensitivity, Immediate; Immunoglobulin E; Leukocytes; Leukotriene B4; Leukotriene C4; Opsonin Proteins; Zymosan

Infants born prematurely are known to display longstanding bronchial hyperreactivity. The mechanism responsible for this is still unclear. Eosinophils are thought to play a central part in the development of bronchial hyperreactivity in asthma. It was the aim of this study to assess the relation of bronchial hyperresponsiveness to potential markers of eosinophilic inflammation in peripheral blood. Eosinophil count, the concentration of serum eosinophilic cationic protein, the capacity of purified eosinophils to generate leukotriene C4, and bronchial reactivity was studied in 24 non-atopic children born prematurely, 12 healthy controls, and 12 children with asthma aged 6 to 9 years. There was no difference in serum concentrations on eosinophil cationic protein and eosinophil counts. However, eosinophils from the 15 formerly preterm infants with significant bronchial hyperreactivity generated significantly higher amounts of leukotriene C4 than normal controls and prematurely born children without bronchial hyperreactivity. Levels of leukotriene C4 in this group were comparable with those obtained with eosinophils from patients with asthma. In contrast with cells from the other groups, eosinophils from the children with bronchial hyperreactivity born prematurely show no enhancement of leukotriene C4 generation on prestimulation with platelet activating factor. It is concluded that bronchial hyperreactivity of children born prematurely is accompanied by the prestimulation of eosinophils.

Topics: Asthma; Bronchial Hyperreactivity; Child; Eosinophils; Forced Expiratory Volume; Humans; Infant, Newborn; Infant, Premature; Leukocyte Count; Leukotriene C4; Vital Capacity

Topics: Airway Obstruction; Asthma; Bronchoconstriction; Humans; Leukotriene Antagonists; Leukotriene B4; Leukotriene C4; Leukotriene E4; Leukotrienes

Urinary leukotriene E4 (LTE4) increases during exacerbations of asthma and following antigen challenge. We determined whether urinary LTE4 excretion reflects sulphidopeptide leukotrienes in the airways of asthmatic patients. Urinary LTE4 concentration was measured prior to and 1.5 and 3.5 h following inhalation of bronchoconstrictive doses of leukotriene C4 (LTC4) or LTE4 in eight asthmatic subjects. Increasing doses of agonist were inhaled until a 35% fall in specific airways conductance (sGaw) was achieved. There was no significant difference between the 53 +/- 3% (mean +/- SEM) fall in sGaw following inhalation of LTC4 (63.1 ng geometric mean, GM, range 5.8-527.5 ng) and the 43 +/- 4% fall in sGaw following inhalation of LTE4 7.94 ng/GM (range 132-3701 ng). The LTE4 excretion rate increased significantly from 2.95 (range 0.6-17.5) ng.h-1 to 4.67 (range 0.8-20) ng.h-1 at 1.5 h following LTC4 inhalation; and from 1.8 (range 0.07-6.7) ng.h-1 to 6.9 (range 2.9-27.3) ng.h-1 at 1.5 h following LTE4 inhalation; and had returned from baseline by 3.5 h. There was a correlation between the dose of LTC4 inhaled and LTE4 excreted in the urine (r = 0.82 and r = 0.72, respectively). The % recovery of LTE4 in the urine, of the total dose of inhaled LTC4 or LTE4 administered, was 6.9 +/- 4.1% and 0.8 +/- 0.3%, respectively. Thus, inhalation of bronchoconstricting doses of LTC4 or LTE4 alter urinary LTE4 excretion in a dose-dependent fashion. This indicates that urinary LTE4 can be used as a marker of sulphidopeptide leukotriene synthesis in the lungs of patients with asthma.

Topics: Administration, Inhalation; Adolescent; Adult; Asthma; Female; Humans; Leukotriene C4; Leukotriene E4; Male; Middle Aged

To determine whether pemirolast, a new antiallergic drug, inhibits the activation of eosinophils, we investigated the effect of pemirolast on the release of leukotriene C4 (LTC4) and eosinophil cationic protein (ECP) from human eosinophils. Calcium ionophore A23187 caused both LTC4 and ECP release from human eosinophils, whereas PAF and FMLP induced only ECP release from the eosinophils. Pemirolast (10(-6) to 10(-3) M) inhibited A23187-induced LTC4 release from the eosinophils in a dose-dependent fashion with 77% inhibition at 10(-3) M. Pemirolast (10(-5) to 10(-3) M) inhibited A23187-induced ECP release from the eosinophils in a dose-dependent fashion with 42% inhibition at 10(-3) M. Pemirolast (10(-4) and 10(-3) M) also inhibited PAF-induced and FMLP-induced ECP release from the eosinophils. We conclude that pemirolast prevents the activation of human eosinophils to inhibit LTC4 and ECP release. These results suggest that pemirolast might be useful in controlling allergic diseases by inhibiting eosinophil activation.

Topics: Asthma; Blood Proteins; Calcimycin; Eosinophil Granule Proteins; Eosinophils; Humans; In Vitro Techniques; Leukotriene C4; N-Formylmethionine Leucyl-Phenylalanine; Platelet Activating Factor; Pyridines; Pyrimidinones; Ribonucleases; Secretory Rate

To assess the contribution of the leukotrienes, LTC4, D4, E4 and B4 during bronchial asthma attacks, simultaneous determination was made of their levels in venous blood. 25 patients with bronchial asthma (15 atopic types, 10 non-atopic types) participated in this study and 4 normal controls were used. Samples were obtained using heparinized syringe from the patients before treatment. A radioimmunoassay was conducted to measure LTs after purification with a Sep-pak column and separation by HPLC. In normal subjects, the levels were less than the minimal detectable amounts. LTC4, D4, E4 and B4 during asthmatic attacks were 100 +/- 179, 88 +/- 116, 479 +/- 291, and 55 +/- 73 (Mean +/- SD) pg/ml respectively (n = 27). Peptide LTs in remission were below minimal detectable levels. LTD4 in patients with moderate attacks was significantly (p < 0.05) higher than in those with mild attacks. Peptide LTs in moderate attack exceeded those in mild attacks, although not to a statistically significant degree. No significant differences in LT during attacks could be detected in atopic or non-atopic type patients. LTs would thus appear importantly involved in asthmatic attacks in atopic and non-atopic type patients, although other chemical mediators may give rise to airway inflammation.

Topics: Adolescent; Adult; Aged; Asthma; Chromatography, High Pressure Liquid; Female; Humans; Leukotriene B4; Leukotriene C4; Leukotriene D4; Leukotriene E4; Leukotrienes; Male; Middle Aged; Radioimmunoassay

A simple method for purification of basophils from a relatively small volume of blood has been developed, which enables us to collect basophils with a purity of over 80%. Basophils were partially purified from 10-20 ml of citrated whole blood using the discontinuous Percoll density gradient centrifugation technique and then contaminant cells were removed using monoclonal antibodies against CD2, CD19, CD14 and CD16. At the end of the procedure, basophils were > 80% pure with lymphocytes accounting for most of the contaminating cells. When stimulated with anti-IgE or fMLP, histamine release from purified basophils was similar to that from mixed leukocytes. When highly purified basophils were challenged with calcium ionophore A23187, generation of leukotriene C4 (LTC4) was not significantly different between asthmatic patients and normal subjects (45.6 +/- 22.6 vs 52.7 +/- 25.6 ng/10(6) cells). Basophils were capable of generating LTC4 in approximately the same quantities as eosinophils (46.5 +/- 11.7 ng/10(6) cells, n = 3). Furthermore, it has been shown that incubation of basophils and eosinophils with calcium ionophore generates only small quantities of thromboxane B2 (TXB2).

Topics: Antibodies, Anti-Idiotypic; Asthma; Basophils; Blood Cells; Calcimycin; Cell Separation; Centrifugation, Density Gradient; Histamine Release; Humans; Leukotriene C4; N-Formylmethionine Leucyl-Phenylalanine; Thromboxane B2

The effects of long-term glucocorticoid therapy on chemical mediator and cellular reaction in the airways were examined in 69 patients with bronchial asthma. The histamine release induced by Ca ionophore A23187 from cells in the bronchoalveolar lavage (BAL) fluid of atopic asthmatics was significantly lower in the subgroup with steroid-dependent intractable asthma (SDIA) than in non-SDIA patients (p < 0.05). In contrast, histamine release in nonatopic SDIA patients did not differ from nonatopic non-SDIA patients. The release of leukotriene C4 (LTC4) was significantly lower in atopic patients with SDIA (p < 0.02). However, there was no significant difference in LTC4 release between nonatopic patients with SDIA and without SDIA. The proportion of BAL lymphocytes was significantly lower in atopic patients with SDIA than in those without it (p < 0.05), although there was no significant difference between the nonatopic patients with and without SDIA. These results show that glucocorticoids affect humoral and cellular events in the airways of atopic asthmatics more than in those of nonatopic asthmatics.

Topics: Adult; Aged; Asthma; Bronchi; Bronchoalveolar Lavage Fluid; Female; Glucocorticoids; Histamine Release; Humans; Leukotriene C4; Male; Methacholine Chloride; Middle Aged; Substance-Related Disorders

Leukotrienes (LT) are synthesized in the lung during asthmatic reactions and mediate certain inflammatory symptoms. Pulmonary metabolism and clearance of exogenously added peptidoleukotrienes were studied in nonasthmatics, asthmatics, and asthmatics challenged with allergen. [3H]LTC4 and [14C]dextran were instilled into the airways, and bronchoalveolar lavage fluid (BALF) was obtained 15 min later. After comparing the [3H]/[14C] ratio of the instilled solution with that in BALF, 77% of LT were found to have been removed from the airways of nonasthmatics, and 72% of unchallenged asthmatics. Allergen administration to asthmatics 1 min before LT instillation inhibited LT transfer out of the airways by 26%, compared with asthmatics not challenged with allergen. This decrease in the removal of LT from the airways during allergic reactions could potentiate the physiologic effects of LT produced in the airways. The predominant LT in BALF was LTE4, constituting 56% of the LT in asthmatics and 61% in nonasthmatics. The percentage of LTE4 in BALF increased to 87% in allergen-stimulated asthmatics (p < 0.05 compared with the two other groups), this again reflecting decreased transfer of LT out of the lung rather than an increase in metabolism. Urinary excretion of LT metabolites occurred rapidly, the majority being excreted excreted within 6 h after instillation. LTE4, the major urinary LT metabolite identified by high-performance liquid chromatography, was a similar percentage concentration in the three groups and, thus, can be accurately used as an index of LT synthesis.

Topics: Adult; Allergens; Asthma; Bronchoalveolar Lavage Fluid; Chromatography, High Pressure Liquid; Dextrans; Female; Humans; In Vitro Techniques; Leukotriene C4; Leukotriene E4; Lung; Male; Middle Aged

We wanted to determine whether the airway response to inhaled leukotriene C4 (LTC4) is similar to inhaled leukotriene E4 (LTE4) in aspirin-sensitive asthma and, therefore, determined airway responsiveness to histamine, LTC4 and LTE4 in seven aspirin-sensitive subjects and 13 control asthmatic subjects, who were tolerant of aspirin. The concentration of inhaled lysine-aspirin which produced a 15% fall in forced expiratory volume in one second (FEV1) (PC15) was determined in aspirin-sensitive asthmatic subjects. The dose of histamine, LTC4 and LTE4 which produced a 35% fall in specific airways conductance (PD35sGaw) was determined by linear interpolation from the log dose response curve. There was no correlation between the PC15 for lysine-aspirin and the airway reactivity to inhaled LTC4 or LTE4. There was no difference in airway response to histamine and LTC4 between any of the groups of asthmatic subjects. There was a rank order of potency LTC4 > LTE4 > histamine in both groups, with LTC4 approximately 1,000 fold more potent than histamine in both groups. Aspirin-sensitive asthmatic subjects were significantly more responsive to LTE4 (p = 0.02) than aspirin-tolerant asthmatic subjects. The relative responsiveness of LTE4 to histamine (PD35 histamine/PD35 LTE4) was significantly greater in aspirin-sensitive asthmatic subjects compared to aspirin-tolerant asthmatic subjects (p = 0.05). There was no difference in relative responsiveness of LTC4 to histamine between aspirin-sensitive or aspirin-tolerant asthmatic subjects. We conclude that the airways of aspirin-sensitive asthmatic subjects demonstrate a selective hyperresponsiveness to LTE4, which is not observed for LTC4.

Topics: Adolescent; Adult; Aspirin; Asthma; Female; Forced Expiratory Volume; Histamine; Humans; Leukotriene C4; Leukotriene E4; Lysine; Male; Middle Aged; Respiratory System

Topics: Aspirin; Asthma; Humans; Leukotriene C4; Leukotriene D4; Leukotriene E4; Leukotrienes