leukotriene-b4 and Nasal-Obstruction

Allergic rhinitis symptoms of itching, sneezing, rhinorrhea, and nasal obstruction significantly decrease patients' quality of life. Compared with histamine and leukotriene receptor antagonists, the petasol butenoate complex Ze 339 displays pharmacologically distinct properties. In vitro it inhibits the biosynthesis of leukotrienes and mediator release from activated eosinophils.. This study aimed to assess the efficacy and mode of action of Ze 339, desloratadine, and placebo on allergic rhinitis symptoms, nasal airflow, and local mediator levels after unilateral nasal allergen provocation.. In this double-blind, randomized, crossover study 18 subjects with allergic rhinitis to grass pollen received Ze 339, desloratadine, and placebo for 5 days before nasal allergen challenge with grass pollen extract. Rhinomanometry, symptom assessment, and local inflammatory mediator measurement were performed during the 24 hours after allergen challenge.. With Ze 339, the patient's time to recovery (5.4 ± 1.6 hours) from nasal obstruction after allergen challenge (time for return to 90% of baseline value ± SEM) was significantly shorter than with placebo (9.1 ± 2.3 hours, P = .035) and desloratadine (10.7 ± 2.5 hours, P = .022). Likewise, Ze 339's standardized symptom assessment for nasal obstruction (3.2 ± 1.3 hours) showed significantly faster relief (time for return to baseline value ± SEM compared with placebo, 8.3 ± 2.4 hours; P = .027) and desloratadine (4.5 ± 1.2 hours, P = .030). One interesting finding was that Ze 339 significantly reduced IL-8 and leukotriene B(4) levels in nasal secretions before challenge.. When compared with desloratadine and placebo, Ze 339 shows better efficacy in relieving nasal obstruction symptoms and inhibiting critical components of the chemokine network and as such represents a novel symptomatic and possible prophylactic treatment for allergic rhinitis.

Topics: Adult; Allergens; Anti-Allergic Agents; Bronchial Provocation Tests; Chemokines; Cross-Over Studies; Cytokines; Double-Blind Method; Female; Humans; Interleukin-8; Leukotriene B4; Loratadine; Male; Middle Aged; Nasal Obstruction; Plant Extracts; Pollen; Rhinitis, Allergic, Seasonal; Young Adult

The clinical importance of leukotrienes in human allergy has not been defined, in part because there have been no selective 5-lipoxygenase inhibitors that have been effective and safe for use in humans. To address the hypothesis that stimulated leukotriene synthesis causes symptoms of immediate-hypersensitivity reactions in vivo, I investigated the effects of a new 5-lipoxygenase inhibitor, A-64077, on provoked allergic nasal symptoms and mediator release in a double-blind, randomized, placebo-controlled study. Eight subjects with allergic rhinitis underwent nasal challenge on two occasions after an oral dose of 800 mg of A-64077 or an identical-appearing placebo.. Allergen-induced nasal congestion was significantly attenuated (P less than 0.02) by A-64077; peak levels of leukotriene B4 (median, 684 pg per milliliter) and 5-hydroxyeicosatetraenoic acid (median, 704 pg per milliliter) in nasal-rinse fluids were markedly reduced (to 67 and 185 pg per milliliter, respectively; P less than 0.01), whereas levels of prostaglandin D2 were not. Histamine release and sneezing were not reduced significantly by A-64077, but there was a significant correlation (P less than 0.01) between the changes in these variables within subjects. The mean (+/- SEM) stimulated synthesis of leukotriene B4 in whole blood ex vivo was markedly reduced by A-64077 (from 153 +/- 19 to 20 +/- 9 ng per milliliter, P less than 0.01), and the specificity of A-64077 for 5-lipoxygenase inhibition was verified by its lack of effect on the synthesis of serum thromboxane B2 or 12-hydroxyeicosatetraenoic acid.. These results provide direct evidence of an important role for the 5-lipoxygenase products of arachidonic acid in allergic rhinitis and support the notion that further experiments in this area may lead to new therapeutic approaches to allergic disorders.

Topics: Double-Blind Method; Female; Histamine Release; Humans; Hydroxyeicosatetraenoic Acids; Hydroxyurea; Leukotriene B4; Leukotrienes; Lipoxygenase Inhibitors; Male; Nasal Obstruction; Nasal Provocation Tests; Prostaglandin D2; Rhinitis, Allergic, Perennial; Rhinitis, Allergic, Seasonal; Sneezing

Allergic rhinitis is an inflammatory disease associated with local leukotriene release during periods of symptoms. Zileuton, a leukotriene synthesis inhibitor, is known to inhibit the release of leukotriene B4. Because we previously showed that leukotriene B4 is a potent mediator of neutrophil-dependent nasal secretion, we investigated whether Zileuton inhibited allergen-induced nasal secretion. Using a newly developed method for isolating and superfusing a nasal segment, we examined the effect of Zileuton on nasal secretion and neutrophil recruitment in ragweed-sensitized dogs. Instillation of ragweed into the nasal segment caused time-dependent increases in the volume of airway fluid and the recruitment of neutrophils. Zileuton prevented ragweed-induced neutrophil recruitment and nasal secretion. These results indicate that leukotrienes are important mediators of allergy-induced nasal secretion in dogs. Future clinical studies in allergic patients will determine whether there is a therapeutic role for leukotriene synthesis inhibitors in modulating neutrophil recruitment and hypersecretion in the nose.

Topics: Animals; Dogs; Hydroxyurea; Hypersensitivity; Leukotriene Antagonists; Leukotriene B4; Nasal Mucosa; Nasal Obstruction; Nasal Provocation Tests; Neutrophils; Plants; Pollen; Rhinitis, Allergic, Seasonal; Time Factors