Inhibition of nasal polyp mast cell and eosinophil activation by desloratadine

Efficacy of Desloratadine and Levocetirizine in Patients with Cedar Pollen-Induced Allergic Rhinitis: A Randomized, Double-Blind Study

BACKGROUND

No comparative study of antihistamines that differ in structural system has been conducted in allergic rhinitis.

OBJECTIVE

This was a randomized, double-blind, crossover comparative study to verify the efficacy of antihistamines that differ in structural system.

METHODS

A total of 50 patients with moderate or more severe Japanese cedar pollen-induced allergic rhinitis were randomized to receive either placebo, desloratadine 5 mg (a tricyclic), or levocetirizine 5 mg (a piperazine). One dose of the study drug was orally administered at 9 pm on the day before a pollen exposure test, which was performed for 3 h (9 a.m. to 12 p.m.) to assess symptoms in an environmental challenge chamber (ECC). Nasal and ocular symptoms were compared at an airborne pollen level of 8,000 grains/m3. The primary endpoint was mean total nasal symptom score (TNSS) from 120 to 180 min in the ECC. Subjects with a difference of ≥1 in TNSS between 2 drugs were extracted to the relevant drug-responsive group.

RESULTS

The difference in TNSS from placebo was -2.42 (p < 0.0001) with levocetirizine and -1.66 (p < 0.01) with desloratadine, showing that both drugs were significantly more effective than placebo in controlling symptoms, but with no statistically significant difference between the 2 drugs. There were 12 subjects in the desloratadine-responsive group and 24 subjects in the levocetirizine-responsive group, with no contributor to response was detected.

CONCLUSION

Levocetirizine tended to control nasal symptoms more effectively than desloratadine. However, the response to each antihistamine varied among individuals and the predictors to the response are unknown.

CLINICAL TRIAL REGISTRATION NUMBER

UMIN ID: UMIN000029653.

Antihistaminic, anti-inflammatory, and antiallergic properties of the nonsedating second-generation antihistamine desloratadine: a review of the evidence

The allergy cascade presents widespread inflammatory and proinflammatory activation, robust cytokine and chemokine signaling, and heterogeneous immune and endothelial responses that lead ultimately to the manifestations of allergic reaction. Histamine, a small peptide with inherent vasoactive properties, is released from granules contained within mast cells, basophils, lymphocytes, and other reservoirs and interacts with histamine receptors to regulate numerous cellular functions involved in allergic inflammation and immune modulation. Of the known histamine receptors, the H(1)-receptor is most clearly associated with potentiation of proinflammatory immune cell activity and enhanced effector function and is the prime focus of suppressive therapy. Second-generation oral H(1)-antihistamines, such as cetirizine, desloratadine, fexofenadine, levocetirizine, and loratadine, are mainstays of allergy treatment, acting as highly specific, long-acting H(1)-receptor agonists at its unique receptor. The ongoing identification of immune effector cells and mediators involved in the allergic cascade indicates that further research is necessary to define the role of antihistamines such as desloratadine in anti-inflammatory therapy.

Enhanced release of IgE-dependent early phase mediators from nasal polyp tissue

Background

The mast cell is a crucial effector cell in allergic rhinitis and other inflammatory diseases. During the acute allergic reaction preformed mediators such as histamine, but also de novo produced mediators such as leukotrienes (LTC₄/D₄/E₄) and prostaglandins (PGD₂) are released. Mast cells represent targets for therapeutic intervention, and thus a human ex-vivo model to stimulate mast cells taken from mucosal sites would be instrumental for drug intervention studies. We have aimed to activate mast cells within ex-vivo human nasal tissue by IgE/anti-IgE specific (ε chain specific) stimulations and in this respect to test the usability of nasal polyps versus inferior turbinates

Methods

Biopsy samples were collected from patients with nasal polyps and inferior turbinates from patients who underwent sinus or septal surgery. Tissue fragments were primed with IgE 1 μg/ml for 60 minutes and then stimulated for 30 minutes with tissue culture medium (negative control), anti-IgE 10 μg/ml, anti-IgE 30 μg/ml and ionomycin 10 μM (positive control). Histamine, leukotrienes and PGD₂ were measured in supernatants. To help provide an understanding of the extent of the response, the number of tryptase and FcεRIα positive cells was evaluated by means of immunohistochemistry and the FcεRIα-chain was measured by means of quantitative PCR in the nasal polyp and inferior turbinate tissues. Finally, the correlation between IgE concentrations in the nasal tissue and the release of mediators was analysed.

Results

Stimulations with anti-IgE on IgE-primed nasal tissue fragments lead to a concentration-dependent release of histamine, leukotrienes and PGD₂. The release of these early phase mediators was significantly higher in nasal polyps compared to inferior turbinates, although tryptase, FcεRIα positive cells and FcεRIα-chain transcripts were equally present in both groups. No correlation was found between baseline concentrations of IgE, and the release of histamine, LTC₄/LTD₄/LTE₄ and PGD₂ after stimulation.

Conclusion

This human nasal challenge model mimics the allergic early phase reaction. The release of histamine, cys-leukotrienes and PGD₂ was significantly higher in nasal polyps versus inferior turbinates, however, this observation could not be explained by differences in mast cell or FcεRI+ cell numbers.

Bibliography. Current world literature. Nose and paranasal sinuses

PURPOSE OF REVIEW

Patients with advanced head and neck cancer are being treated with chemo-radiotherapy, and life is being prolonged, with or without persistent disease, for longer than was previously. Hypercalcaemia may present in patients with advanced or disseminated head and neck cancer, and, as such, these patients may present to a larger variety of clinicians for advice concerning their symptoms and illness. Modes of presentation of hypercalcaemia and treatment strategies are reviewed.

RECENT FINDINGS

There were previously few large series of head and neck cancer patients diagnosed with hypercalcaemia, which may or may not have been related to their cancer being treated. Investigations, by way of blood/serum calcium level, may identify such patients. Patients with cancer-related hypercalcaemia have a poor prognosis, but many may respond temporarily to treatment when offered, with an improvement of their quality of life and death.

SUMMARY

Hypercalcaemia should and must be considered in all patients who have or possibly have a diagnosis of a head and neck cancer and who present unwell with symptoms of fatigue, lethargy and somnolence. Investigation must include serum calcium (corrected for serum albumin binding) and parathyroid hormone level. Patients may be treated by a combination of rehydration and bisulphonate therapy until the serum calcium is reduced to a level below 3 mmol/l. The majority of patients diagnosed with hypercalcaemia due to head and neck malignancy die of their diseases in the short term, but some may enjoy a prolongation of life with reasonable quality if diagnosed and treated aggressively.

Review of desloratadine for the treatment of allergic rhinitis, chronic idiopathic urticaria and allergic inflammatory disorders

Desloratadine is a once-daily, non-sedating, non-impairing, selective histamine H1-receptor antagonist. It relieves the symptoms of seasonal allergic rhinitis (including nasal obstruction and congestion, and morning symptoms), perennial allergic rhinitis and chronic idiopathic urticaria by blocking multiple critical steps in the systemic allergic cascade and downregulating key allergy-induced inflammatory mediators. It also relieves asthma symptoms and decreases rescue medication use in patients with seasonal allergic rhinitis and comorbid asthma. Numerous clinical studies have demonstrated that desloratadine is safe, well tolerated and free of serious cardiac effects. Pharmacokinetic studies have demonstrated a low propensity for drug-drug or drug-food interactions. This review outlines the mechanism of action, efficacy and safety of desloratadine for the treatment of allergic inflammatory disorders.

The effect of 4 weeks treatment with desloratadine (5mg daily) on levels of interleukin (IL)-4, IL-10, IL-18 and TGF beta in patients suffering from seasonal allergic rhinitis

Anti-inflammatory effect of desloratadine (DL), including, but not limited to depression of production of IL-4, IL-6 and IL-8, has been shown in several in vitro experiments but only a few in vivo studies refer to this findings. The purpose of our study was to evaluate the influence of DL on levels of IL-4, IL-10, IL-18 and TGF-beta in sera of patients with seasonal allergic rhinitis (SAR). Sixty-nine subjects suffering from SAR with hypersensitivity to grass pollen were included into the evaluation of clinical efficacy of DL (5mg once daily). None of them was taking any H(1) receptor antagonist during the pollen season before inclusion into the study. Samples of peripheral blood were taken before and after 4 weeks of treatment. Levels of cytokines were determined using the ELISA method. The mean level of IL-4 was 0.212+/-0.07pg/ml before and 0.221+/-0.1pg/ml after the treatment (p=0.52); IL-10 5.13+/-3.14 and 4.71+/-0.88 (p=0.69); IL-18 54.45+/-26.09 and 44.80+/-22.42 (p=0.48); TGF beta 949.17+/-401.5 and 955.7+/-391.2 (p=0.97)pg/ml before and after the treatment, respectively. Unless in vitro DL demonstrates not only anti-allergic but also anti-inflammatory activities data from this in vivo study in a group of patients suffering from SAR do not support previous pre-clinical findings.

Pathogenesis of nasal polyps: an update

The cause of nasal polyp formation is still unknown. Genetic predisposition has been suggested, but there are scanty data to support such theories. Activated epithelial cells may be the major source of mediators inducing influx of inflammatory cells (mostly eosinophils) and proliferation and activation of fibroblasts leading to nasal polyp formation. Infectious agents (including viruses, bacteria, or fungi) may be potential primary factors activating nasal epithelial cells. Proinflammatory cytokines and growth factors play important roles in the persistence of mucosal inflammation associated with nasal polyps. Arachidonic acid metabolites seem to be particularly important in the pathogenesis of nasal polyps in patients with aspirin hypersensitivity rhinosinusitis/asthma syndrome.

Desloratadine reduces systemic allergic inflammation following nasal provocation in allergic rhinitis and asthma patients

BACKGROUND

Preclinical studies have demonstrated that some second-generation antihistamines have anti-inflammatory effects. It is not known whether these effects are also demonstrable in vivo. In this study we investigated the effect of treatment with desloratadine (DL) on systemic inflammation and on nasal and bronchial mucosal inflammation after nasal allergen provocation (NP) in subjects with grass-pollen-allergic rhinitis and asthma.

METHODS

Twenty-six subjects with grass-pollen-allergic rhinitis and asthma were randomly allocated to 8 days of treatment with DL (n = 13) or placebo (n = 13) outside the grass pollen season. On day 7 they underwent nasal provocation with grass pollen allergen. Nasal and bronchial biopsies were taken for immunohistochemical evaluation, and blood samples were analysed. Rhinitis and asthma symptoms, peak nasal inspiratory flow and peak expiratory flow, were also measured at specified times.

RESULTS

The number of circulating eosinophils decreased during DL treatment, and there was a reduced increase in circulating eosinophils after NP in these subjects. There was also a significant reduction in early bronchial clinical response. There was no significant lessening in the severity of the nasal symptoms. Nasal and bronchial mucosal inflammation parameters did not alter under DL treatment.

CONCLUSION

These data suggest that treatment with DL reduces systemic eosinophilia and prevents the increase in circulating eosinophils after NP. DL also significantly reduces the early bronchial clinical response to NP. However, airway mucosal inflammation is not altered by 1 week of treatment.